| United States Patent Application |
20200261645
|
| Kind Code
|
A1
|
|
Kamen; Dean
;   et al.
|
August 20, 2020
|
PATCH-SIZED FLUID DELIVERY SYSTEMS AND METHODS
Abstract
A patch-sized fluid delivery device may include a reusable portion and a
disposable portion. The disposable portion may include components that
come into contact with the fluid, while the reusable portion may include
only components that do not come into contact with the fluid. Redundant
systems, such as redundant controllers, power sources, motor actuators,
and alarms, may be provided. Alternatively or additionally, certain
components can be multi-functional, such a microphones and loudspeakers
that may be used for both acoustic volume sensing and for other functions
and a coil that may be used as both an inductive coupler for a battery
recharger and an antenna for a wireless transceiver. Various types of
network interfaces may be provided in order to allow for remote control
and monitoring of the device.
| Inventors: |
Kamen; Dean; (Bedford, NH)
; Gray; Larry B.; (Merrimack, NH)
|
| Applicant: | | Name | City | State | Country | Type | DEKA Products Limited Partnership | Manchester | NH | US | | |
| Family ID:
|
38805798
|
| Appl. No.:
|
16/866063
|
| Filed:
|
May 4, 2020 |
Related U.S. Patent Documents
| | | | |
|
| Application Number | Filing Date | Patent Number | |
|---|
| | 12395193 | Feb 27, 2009 | 10639418 | |
| | 16866063 | | | |
| | 11704886 | Feb 9, 2007 | 8545445 | |
| | 12395193 | | | |
| | 11704899 | Feb 9, 2007 | 8414522 | |
| | 12395193 | | | |
| | 11704896 | Feb 9, 2007 | 8585377 | |
| | 11704899 | | | |
| | 11704897 | Feb 9, 2007 | 8113244 | |
| | 11704896 | | | |
| | 60772313 | Feb 9, 2006 | | |
| | 60789243 | Apr 5, 2006 | | |
| | 60793188 | Apr 19, 2006 | | |
| | 60889007 | Feb 9, 2007 | | |
|
|
| Current U.S. Class: |
1/1 |
| Current CPC Class: |
G05B 23/02 20130101; A61M 2005/1583 20130101; A61M 2205/502 20130101; A61B 5/1427 20130101; A61M 2005/14506 20130101; A61M 2205/50 20130101; A61M 5/14586 20130101; A61M 5/16831 20130101; A61M 2205/0266 20130101; A61M 2205/04 20130101; A61M 2205/3569 20130101; A61M 2207/00 20130101; A61M 2005/1585 20130101; F04B 43/1253 20130101; A61M 5/365 20130101; F04B 43/02 20130101; A61M 5/14212 20130101; A61M 5/14216 20130101; A61M 2205/583 20130101; A61M 5/1452 20130101; A61M 5/16804 20130101; G08C 17/02 20130101; A61M 5/5086 20130101; A61M 2005/14268 20130101; A61M 5/14244 20130101; G05D 7/0647 20130101; A61B 5/0024 20130101; A61M 5/14248 20130101; A61M 2205/18 20130101; Y10T 29/49236 20150115; G01F 22/00 20130101; A61B 2560/0412 20130101; A61M 2205/3331 20130101; A61M 2205/52 20130101; H04B 7/2609 20130101; Y10T 29/49412 20150115; Y10T 29/49826 20150115; A61M 5/142 20130101; Y10T 29/49828 20150115; A61B 5/6833 20130101; A61M 5/16886 20130101; A61M 2205/8206 20130101; A61M 5/168 20130101; A61M 2205/3576 20130101; A61M 2230/201 20130101; A61M 2005/14252 20130101; A61M 2205/3337 20130101; A61M 5/172 20130101; A61M 5/1723 20130101; A61M 2205/3546 20130101; A61M 2205/581 20130101; F04B 7/00 20130101; Y10T 29/494 20150115; A61M 2005/16863 20130101; A61J 1/20 20130101; A61M 2005/1586 20130101; A61M 2205/3379 20130101; F04B 43/09 20130101; A61M 5/16809 20130101; A61M 2209/045 20130101; A61M 5/14224 20130101; A61M 2005/1402 20130101; A61M 2005/14208 20130101; A61M 2205/0294 20130101; A61M 2205/3592 20130101; A61M 5/1413 20130101; A61M 2205/3368 20130101; A61M 2205/3375 20130101; A61M 2206/22 20130101; G05D 7/0676 20130101; A61M 2205/3303 20130101; A61M 2205/582 20130101; A61M 2205/8237 20130101; A61M 5/162 20130101; A61M 5/158 20130101; A61M 5/16813 20130101; A61M 2205/16 20130101; A61M 2205/3523 20130101 |
| International Class: |
A61M 5/168 20060101 A61M005/168; A61M 5/50 20060101 A61M005/50; F04B 43/12 20060101 F04B043/12; F04B 43/09 20060101 F04B043/09; A61J 1/20 20060101 A61J001/20; A61B 5/155 20060101 A61B005/155; A61M 5/36 20060101 A61M005/36; A61M 5/142 20060101 A61M005/142; A61M 5/162 20060101 A61M005/162; A61M 5/14 20060101 A61M005/14; G01F 22/00 20060101 G01F022/00; A61B 5/00 20060101 A61B005/00; A61M 5/172 20060101 A61M005/172; A61M 5/158 20060101 A61M005/158; A61M 5/145 20060101 A61M005/145; G05B 23/02 20060101 G05B023/02; H04B 7/26 20060101 H04B007/26; G08C 17/02 20060101 G08C017/02; G05D 7/06 20060101 G05D007/06; F04B 43/02 20060101 F04B043/02 |
Claims
1. A reservoir for a drug delivery device, the reservoir having a
greatest depth, the reservoir comprising: a first rigid body having a
first face and an opposing second face, the first face having a first
face first region and a first face second region surrounded by the first
face first region, the first face second region being recessed a variable
depth with respect to the first face first region; a second body formed
from flexible material, the second body having an attachment region
operably coupled with the first face first region, the second body and
the first face first region forming an interior volume of the reservoir,
the interior volume configured to hold a medicament volume of medicament;
an access port raised from the first rigid body, the access port being
formed as a continuous part of the first rigid body; and a channel
extending from a first opening in an exterior face of the access port
through the access port to a second opening into the interior volume, the
channel forming a straight line from the first opening in the exterior
face of the access port extending along an axis of a portion of the
channel, the channel passing through a wall before extending into the
interior volume.
2. The reservoir of claim 1, wherein the reservoir further comprises a
piercable septum disposed in the channel.
3. The reservoir of claim 2, wherein the piercable septum, in an
unpierced state, seals the medicament volume within the reservoir when
the interior volume is filled with the medicament volume.
4. The reservoir of claim 1, wherein the medicament volume is pre-filled
into the reservoir.
5. The reservoir of claim 1, wherein the medicament volume fills the
interior volume of the reservoir to a non-pressurized state when the
reservoir is in a filled state.
6. The reservoir of claim 1 further comprising a guard, the guard
including the second opening into the interior volume.
7. The reservoir of claim 6, wherein the second opening into the interior
volume comprises a passage through the guard, the guard being spaced a
distance from the axis.
8. The reservoir of claim 1, wherein the second opening into the interior
volume is disposed within a footprint of the first face second region.
9. The reservoir of claim 1, wherein the first opening in the exterior
face of the access port is disposed within a footprint of the first face.
10. The reservoir of claim 1, wherein the variable depth comprises the
greatest depth in a central region of the first face second region.
11. The reservoir of claim 1, wherein the variable depth comprises a
value in a range of the greatest depth to approximately a surface of the
first face first region.
12. The reservoir of claim 1, wherein the variable depth comprises a
continuously variable value in a range of the greatest depth to a depth
closer to approximately a surface of the first face first region.
13. The reservoir of claim 1, wherein the variable depth is defined by a
curvature of the first face second region.
14. The reservoir of claim 1, wherein a periphery of the first face
second region comprises a substantially round shape.
15. The reservoir of claim 1, wherein a periphery of the first face first
region comprises a substantially round shape.
16. The reservoir of claim 1, wherein the reservoir comprises a patch
type drug delivery device.
17. A reservoir for a drug delivery device, the reservoir including a
greatest depth, the reservoir comprising: a first rigid body having a
first face and an opposing second face, the first face having a first
face first region and a first face second region surrounding the first
face first region, the first face second region being recessed a variable
depth with respect to the first face first region; a second body formed
from flexible material, the second body having an attachment region
welded onto the first face first region, the second body and the first
face first region forming an interior volume of the reservoir, the
interior volume holding a medicament volume; an access port projecting
outwardly from the first rigid body, the access port forming a continuous
part of the first rigid body; and a channel extending from a first
opening in an exterior face of the access port to a second opening into
the interior volume, the channel forming a straight line segment from the
first opening in the exterior face of the access port extending toward
the interior volume along an axis of a majority of the channel, the
channel passing into a wall without extending into the interior volume.
18. The reservoir of claim 17, wherein the reservoir comprises a
pre-filled reservoir.
19. The reservoir of claim 17, wherein the medicament volume of
medicament fills the interior volume of the reservoir to a
non-pressurized state when the reservoir is in a filled state.
20. The reservoir of claim 17 further comprising a guard, the guard
including the second opening into the interior volume.
21. The reservoir of claim 20, wherein the second opening into the
interior volume comprises a passage through the guard, the guard being
spaced from the axis.
22. The reservoir of claim 17, wherein the second opening into the
interior volume is disposed within a footprint of the first face second
region.
23. The reservoir of claim 17, wherein the variable depth comprises the
greatest depth in a central region of the first face second region.
24. The reservoir of claim 17, wherein the variable depth comprises a
value in a range of the greatest depth to approximately a surface of the
first face first region.
25. The reservoir of claim 17, wherein the variable depth comprises a
continuously variable value in a range of the greatest depth to a depth
closer to approximately a surface of the first face first region.
26. The reservoir of claim 17, wherein the variable depth is defined by a
curvature of the first face second region.
27. The reservoir of claim 17, wherein a periphery of at least one of the
first face second region and the first face first region comprises a
substantially round shape.
28. A cassette for a drug delivery device comprising: a first body having
a first face and an opposing second face, the first body formed of rigid
plastic, the first face having a first face first region and a first face
second region, the first face first region surrounding the first face
second region, the first face first region being substantially planar,
the first face second region being recessed a variable depth with respect
to the first face first region; a second body formed from flexible
material, the second body having an attachment region welded onto the
first face first region, the second body and the first face first region
forming an interior volume of a reservoir, the interior volume of the
reservoir being variable based on a displacement of the second body; an
access port raised from the first body, the access port being formed as a
continuous part of the access port; a channel extending from a first
opening in an exterior face of the access port to a second opening into
the interior volume, the channel forming a straight line segment from the
first opening in the exterior face of the access port extending toward
the interior volume along an axis of a majority of the channel and
passing into a wall without extending into the interior volume; and a
piercable septum disposed in the channel, the piercable septum, in an
unpierced state, sealing a medicament volume within the reservoir, the
medicament volume being pre-filled into the reservoir, the medicament
volume filling the interior volume of the reservoir to a non-pressurized
state.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser.
No. 12/395,193, filed on Feb. 27, 2009 and entitled Patch-Sized Fluid
Delivery Systems and Methods, now U.S. Pat. No. 10,639,418, issued May 5,
2020 (Attorney Docket No. H17), which is a continuation of U.S. patent
application Ser. No. 11/704,886, filed on Feb. 9, 2007 and entitled
Patch-Sized Fluid Delivery Systems and Methods, now U.S. Pat. No.
8,545,445, issued Oct. 1, 2013 (Attorney Docket No., 1062.E72), the
entire disclosures of which are incorporated herein by reference.
[0002] U.S. patent application Ser. No. 11/704,886 also claims the benefit
of the following U.S. Provisional patent applications, all of which are
herein incorporated by reference in their entireties:
[0003] Ser. No. 60/772,313 filed Feb. 9, 2006 and entitled Portable
Injection System (Attorney Docket No. 1062.E42); Ser. No. 60/789,243
filed Apr. 5, 2006 and entitled Method of Volume Measurement for Flow
Control (Attorney Docket No. 1062.E53); and
[0004] Ser. No. 60/793,188 filed Apr. 19, 2006 and entitled Portable
Injection and Adhesive System (Attorney Docket No. 1062.E46).
[0005] U.S. patent application Ser. No. 12/395,193 is also a continuation
of the following U.S. application Serial Numbers, all of which are herein
incorporated by reference in their entireties:
[0006] Ser. No. 11/704,899 filed Feb. 9, 2007 and entitled Fluid Delivery
Systems and Methods, now. U.S. Pat. No. 8,414,522, issued Apr. 9, 2013
(Attorney Docket No. 1062.E70);
[0007] Ser. No. 11/704,896 filed Feb. 9, 2007 and entitled Pumping Fluid
Delivery Systems and Methods Using Force Application Assembly, now U.S.
Pat. No. 8,585,377 issued Nov. 19, 2013 (Attorney Docket No. 1062.E71);
and
[0008] Ser. No. 11/704,897 filed Feb. 9, 2007 and entitled Adhesive and
Peripheral Systems and Methods for Medical Devices, now U.S. Pat. No.
8,113,244 issued Feb. 14, 2012.
FIELD OF THE INVENTION
[0009] This application relates generally to patch-sized fluid delivery
systems and methods.
BACKGROUND
[0010] Many potentially valuable medicines or compounds, including
biologicals, are not orally active due to poor absorption, hepatic
metabolism or other pharmacokinetic factors. Additionally, some
therapeutic compounds, although they can be orally absorbed, are
sometimes required to be administered so often it is difficult for a
patient to maintain the desired schedule. In these cases, parenteral
delivery is often employed or could be employed.
[0011] Effective parenteral routes of drug delivery, as well as other
fluids and compounds, such as subcutaneous injection, intramuscular
injection, and intravenous (IV) administration include puncture of the
skin with a needle or stylet. Insulin is an example of a therapeutic
fluid that is self-injected by millions of diabetic patients. Users of
parenterally delivered drugs would benefit from a wearable device that
would automatically deliver needed drugs/compounds over a period of time.
[0012] To this end, there have been efforts to design portable devices for
the controlled release of therapeutics. Such devices are known to have a
reservoir such as a cartridge, syringe, or bag, and to be electronically
controlled. These devices suffer from a number of drawbacks including the
malfunction rate. Reducing the size, weight and cost of these devices is
also an ongoing challenge.
SUMMARY OF THE INVENTION
[0013] In various embodiments of the present invention, a patch-sized
housing for a fluid delivery system may include a reusable portion and a
disposable portion that is removably engageable with the reusable
portion. In terms of fluid delivery management, the disposable portion
generally includes all of the fluid management components that come into
contact with the fluid (e.g., a fluid path having various valve, pump,
and/or dispensing regions bounded by flexible membrane material), while
the reusable portion generally includes fluid management components that
do not come into contact with the fluid (e.g., various valve actuators,
pump actuators, and sensors that interface with the fluid path through
the flexible membrane material). The reusable portion generally also
includes most, if not all, of the components that would be considered
reusable or non-disposable, such as, for example, a controller, an active
mechanical assembly including a pump with valve and/or pump actuators and
pump motor(s), one or more sensors (e.g., a fluid flow/volume sensor, a
temperature sensor), one or more electrical power sources (e.g., a
rechargeable battery) and related circuitry (e.g., a battery recharging
circuit and a coil for inductively coupling the battery charging circuit
to an external power supply), a network interface (e.g., a wireless
transceiver with antenna, a wireline interface such as USB), and user
interface components (e.g., a pushbutton control). The disposable portion
generally includes single-use or limited-use components relating to fluid
management, but may also include an integral fluid reservoir and other
components, such as a backup power source, a small processor (e.g., to
continue certain device operations in the event of a failure, to generate
an alarm in the event of a failure, or to provide status information to
the reusable portion), and/or an alarm output. The disposable portion may
also include, or be configured to support, so-called "sharps" components
(e.g., a cannula with cannula delivery needle and an analyte sensor) and
an assembly for inserting the sharps into a patient (e.g., a cartridge
that holds the sharps and an actuator for inserting the sharps). The
substrate and the flexible membrane material of the disposable portion
may constitute a fluidic assembly that is configured to fit within a
disposable base.
[0014] In certain embodiments, the disposable portion includes a substrate
having flexible membrane material thereon and incorporating therein a
fluid channel, the fluid channel being part of a fluid path in the
disposable portion from a reservoir port to a cannula port and including
a series of regions exposed to the flexible membrane material, at least
one of such regions being a valve region. The reusable portion includes a
control assembly having an active mechanical assembly that interacts
mechanically with the regions through the membrane material in such a
manner as to achieve pumping of fluid along the fluid path, the active
mechanical assembly including a valve actuator that operates on the valve
region. The disposable portion may also include a pump region, and the
active mechanical assembly may include a pump actuator that operates on
the pump region. The series of regions may be exposed to a single
flexible membrane of the flexible membrane material.
[0015] The active mechanical assembly generally includes a motor for
operation of the valve actuator and/or the pump actuator under control of
the control assembly. The valve actuator and the pump actuator may be
interconnected by a plate for coordinated operation of the valve actuator
and the pump actuator. The motor may include one or more shape-memory
actuators. The motor may include a heater for operating the shape-memory
actuator(s). Alternatively, the shape-memory actuator(s) may be operated
through changes in electrical current passed through at least a portion
of the shape-memory actuator. Multiple shape-memory actuators may be used
for redundancy and/or to provide different modes of operation (e.g., a
normal pumping mode and a high-powered pumping mode). The motor may
include multiple shape-memory actuators of different lengths or gauges.
[0016] The disposable portion may include an integral fluid reservoir or
may include a reservoir interface for coupling with a fluid reservoir.
The reservoir interface may include a cannulated needle for introduction
into the fluid reservoir so as to provide fluid communication between the
fluid reservoir and the fluid path or may include a septum for
penetration by a fluid reservoir cannulated needle so as to provide fluid
communication between the fluid reservoir and the fluid path. At least
one of the reusable portion and the disposable portion may include a
recess for receiving the fluid reservoir. The fluid reservoir and the
corresponding recess may be eccentrically shaped and/or keyed so as to
prevent incorrect orientation of the fluid reservoir within the housing.
[0017] The disposable portion may be configured to support a cannulus in
fluid communication with the fluid path and an analyte sensor in
communication with the control assembly. Interconnection between the
control assembly and the analyte sensor may be established upon
engagement of the reusable portion and the disposable portion. In this
regard, the control assembly may include an analyte sensor interface for
direct interconnection with the analyte sensor. Alternatively, the
communication path between the control assembly and the analyte sensor
may include a portion of the disposable unit or may be wireless.
[0018] One challenge in such a patch-sized device is fitting all of the
components into the reusable and disposable portions while also providing
sufficient space for a fluid reservoir that holds a substantial amount of
fluid and a pump that is capable of delivering a relatively large volume
of fluid per day. Therefore, in certain embodiments of the present
invention, elongated components (e.g., strips of shape-memory material
and/or portions of the fluid path) may be "folded" within the housing,
for example, using coil or serpentine shaped paths. One or more pulleys
may be used to fit a length of shape-memory material into the housing.
[0019] Because the fluid delivery system may be used to deliver
life-critical therapeutic fluids to a patient, it may be advantageous to
have so-called "fail safe" operation so that a device failure will not
allow fluid to be delivered to the patient at an unsafe flow rate.
Therefore, certain embodiments of the present invention include a finite
fluid impedance downstream of the regions so as to prevent delivery of
fluid at an unsafe flow rate. The fluid impedance may be passive and/or
may include a conduit. The conduit may be integral to the disposable unit
(e.g., an in-molded channel) or may be a separate component, such as
tubing. The conduit may have a specified minimum inside diameter (e.g.,
to reduce the likelihood of blockage) such that it may be necessary or
desirable for the conduit to be elongated in order to achieve a desired
impedance. In order to fit such an elongated conduit within the housing,
the conduit may be tortuous (e.g., coiled or serpentine). For further
fail safe operation, the device may operate with a non-pressurized fluid
reservoir so that failure or shut-down of the pump effectively prevents
further delivery of fluid to the patient.
[0020] Particularly in the context of delivering therapeutic fluid to a
patient, it may be necessary or desirable to very precisely measure and
control the volume of fluid delivered to the patient over time. Thus, in
various embodiments of the present invention, the disposable portion may
include in the fluid path a dispensing chamber bounded by flexible
membrane material, and the reusable portion may include a fluid sensor
(e.g., an acoustic volume sensor) in communication with the dispensing
chamber for measuring fluid flow through the dispensing chamber. The
fluid path may include a finite fluid impedance (e.g., of the types
described above) downstream of the dispensing chamber so that the
dispensing chamber membrane expands in response to the pumping of fluid.
A resilient dispensing spring may be provided (e.g., in the reusable
portion or in the dispensing chamber membrane itself) to facilitate
contraction of the dispensing chamber membrane.
[0021] In order to reduce the number of components in the device, it may
be advantageous to utilize certain components for more than one function.
For example, in embodiments that include an acoustic volume sensor having
a loudspeaker and/or a microphone, the loudspeaker may be used to produce
audible alarms, while the microphone may be used to monitor operation of
mechanical components such as a fluid pump (e.g., by "listening" for
sounds and vibrations generated by the mechanical components). Also, in
embodiments that include both a battery recharging circuit and a wireless
transceiver, a single coil (e.g., a solenoid) may be included for both
inductively coupling the battery recharging circuit with an external
power source and conveying radio frequency signals to and from the
wireless transceiver. Also, a user input (e.g., a pushbutton control) may
be included to allow manual control of various functions, such as power
on/off and manual actuation of the pump for such things as priming, air
purging, and emergency delivery of a quantity of fluid.
[0022] It may also be advantageous to eliminate or minimize the number of
user interface components supported by the housing. User interface
components such as a LCD screen and a keyboard can add cost, size,
weight, and complexity to the device as well as consume valuable battery
power. Therefore, rather than including a full-featured user interface in
the device, the user interface may be provided exclusively or partially
through a remote controller that communicates with the device through a
network interface. The network interface may include a wireless interface
(e.g., Bluetooth, infrared) or may include a wireline interface (e.g.,
USB port). The device may include certain types of user inputs, such as a
pushbutton control to allow for manual actuation of the pump (e.g., for
priming, air-purging, or delivering an emergency dose of fluid).
[0023] Particularly in a medical context, it may be necessary or desirable
to include certain redundant systems to reduce the likelihood of complete
device failure. For example, a pump motor may include multiple actuators
(e.g., multiple strands of shape-memory material) in order to maintain
pump operation in the event one of the actuators fails, a backup
electrical power source (e.g., a battery or supercapacitor) may be
included in order to provide electrical power in the event of a failure
of a primary power source (e.g., a rechargeable battery), and multiple
alarm outputs (e.g., audible, visual, tactile, and/or wireless alarm
outputs) may be provided so that status information (e.g., low battery
level, low fluid level, occlusion or air bubble detected, etc.) can be
conveyed to the patient in multiple modes. Also, a backup processor or
controller may be included (e.g., in the disposable portion) to either
continue device operation in the event of a failure of a primary
controller (e.g., in the reusable portion) or at least generate an alarm
to indicate that a failure has occurred.
[0024] It may also be advantageous for the reusable portion to take
certain remedial actions (e.g., prevent or terminate operation of the
device, change a mode of operation of the pump, and/or generate an alarm)
in certain situations. Alarms may include audible alarms (e.g., via a
speaker or buzzer), visual alarms (e.g., via an LED), tactile alarms
(e.g., via a vibrating mechanism), and/or wireless alarms (e.g.,
transmitting an alarm signal to a remote controller or caretaker), to
name but a few. Alarm components may be included in the reusable portion
and/or the disposable portion and may be actuated by a controller in the
reusable portion and/or a controller in the disposable portion. Alarms
may be generated using multiple mechanisms simultaneously or
concurrently.
[0025] For example, the reusable portion may be configured to take
remedial actions upon detection of a fault condition. Fault conditions
may include such things as a low power level, a low fluid level, an
abnormal temperature level, a problem with a primary or backup power
supply, detection of an occlusion, detection of an air bubble, detection
of a fluid leak, detection of abnormal vibration from the pump, and
detection of lack of vibration from the pump, to name but a few.
[0026] Furthermore, the reusable portion may be configured to take
remedial actions upon detection of a problem with any of the disposables,
which may include the disposable portion itself and other types of
disposable components that may be used in or with the disposable portion,
such as, for example, a fluid reservoir and a sharps cartridge (such
components may be integral with the disposable portion or installed into
the disposable portion in various embodiments). For example, upon
engagement of the disposable portion with the reusable portion, the
reusable portion may read or otherwise obtain information about the
disposables such as, for example, manufacturer, model number, serial
number, shelf life, maximum exposure, maximum operation temperature,
expiration date, and safe dispensing limits for the therapeutic, to name
but a few. The reusable portion may obtain such information, for example,
through communication with a processor in the disposable portion, a bar
code reader, and/or RFID technology, to name but a few. If the reusable
portion detects a problem with the disposables (e.g., invalid model
number for use with the reusable portion or expiration date of the fluid
has passed), then the reusable portion may prevent or terminate operation
of the device and generate an appropriate alarm.
[0027] The reusable portion may be configured to generate alarms to
indicate an operational condition. Operational conditions may include
such things as a power on condition, proper operation of the control
assembly, and proper delivery of fluid within a predetermined set of
parameters. In certain embodiments, an alarm may be generated upon an
attempted manual actuation of the pump in order to alert the patient or
caretaker of the attempt and solicit a confirmation before proceeding
with pump actuation.
[0028] The reusable portion may be configured to generate alarms to test
and report on patient responsiveness. For example, the reusable portion
may be configured to test patient responsiveness by generating an alarm
(e.g., an audible and/or tactile alarm) and awaiting a response from the
patient (e.g., actuation of a pushbutton control). Such a test may be
performed at various times (e.g., every five minutes) or upon detection
of a condition such as an abnormal analyte level monitored via an analyte
sensor or an abnormal body temperature monitored via a temperature
sensor. If the patient does not provide an appropriate response within a
predetermined amount of time, the reusable portion may send an alarm to a
remote controller or caretaker. Such testing and reporting might be
particularly valuable for patients who could become unconscious or
incapacitated, either from a device malfunction or otherwise.
[0029] In order to deliver fluid to a patient, the patch-sized device is
typically secured against the skin, for example, using straps or
adhesive. In certain exemplary embodiments, the disposable portion may be
placed against the skin before or after insertion of sharps into the
patient's skin and before or after installation of the fluid reservoir
(if necessary), and the reusable portion may then be engaged with the
disposable portion in order to place the device into an operational
configuration. Alternatively, the entire device may be assembled prior to
placement against the skin. In any case, one or more pads may be situated
between the underside of the disposable portion and the patient's skin so
as to provide separation between the disposable portion and the patent's
skin. The pad(s) may provide, or may be configured to provide, air flow
to a portion of the patient's skin covered by the disposable portion when
placed on the patient (e.g., air flow may be provided by passageways
through the pad, passageways between pads, and/or construction of the at
least one pad from a porous material). The pad(s) may be provided with an
adhesive for securing the device to the patient. Alternatively, the
device may be secured to the patient using tethers that are coupled to
the device and adhesive members for securing the tethers to a patient's
skin.
[0030] It should be noted that the reusable portion, the disposable
portion, the fluid reservoir, and the sharps cartridge may be considered
as separate embodiments of the invention. It is envisioned that these
components will be manufactured separately and will be sold separately or
packaged in different configurations. Thus, for example, one type of kit
might include a reusable unit packaged together with one or more
disposable units. Another type of kit might include a disposable unit and
a sharps cartridge. Other types of kits are of course possible.
[0031] It should also be noted that patches with different combinations of
the described features may be considered as separate embodiments of the
invention. Thus, for example, a patch with a pump and an acoustic volume
sensor, a patch with redundant actuators, a patch with redundant power
sources, a patch with redundant alarms, a patch with redundant
controllers, a patch that is configured to take remedial actions upon
detection of a problem with the disposables, a patch that is configured
to test and report patient responsiveness, and others may be considered
as separate embodiments of the invention.
[0032] Thus, in accordance with one aspect of the invention there is
provided apparatus comprising a patch-sized housing including a reusable
portion and a disposable portion that is removably engageable with the
reusable portion. The disposable portion includes a substrate having
flexible membrane material thereon and incorporating therein a fluid
channel, the fluid channel being part of a fluid path in the disposable
portion from a reservoir port to a cannula port and including a series of
regions exposed to the flexible membrane material, at least one of such
regions being a valve region. The reusable portion includes a control
assembly having an active mechanical assembly that interacts mechanically
with the regions through the membrane material in such a manner as to
achieve pumping of fluid along the fluid path, the active mechanical
assembly including a valve actuator operating on the valve region.
[0033] In various alternative embodiments, the series of regions may be
exposed to a single flexible membrane of the flexible membrane material.
[0034] In other alternative embodiments, the fluid path may include a
fluid impedance (e.g., a passive fluid impedance and/or a tortuous
conduit, which may be an integral part of the fluid channel, may comprise
coiled tubing, may have a serpentine shape, may have a length greater
than a largest dimension of the housing, may have an effective internal
diameter or length selected to provide a predetermined impedance based on
at least one of a viscosity and a density of the fluid, or may have an
internal diameter sufficiently large to prevent occlusion due to flow of
a therapeutic liquid through the conduit) downstream of the regions so as
to prevent pumping of fluid along the path at an unsafe flow rate.
[0035] In still other alternative embodiments, the substrate may include a
dispensing chamber formed in the fluid channel of the substrate, such
chamber bounded by flexible membrane material forming a dispensing
chamber membrane. The fluid path may include a finite fluid impedance
downstream of the dispensing chamber, the fluid impedance sufficiently
high so as to cause the expansion of the dispensing chamber membrane in
response to the pumping of fluid induced by the active mechanical
assembly. The control assembly may include at least a first pump mode in
which the dispensing chamber is permitted to substantially empty between
pump strokes and a second pump mode in which the dispensing chamber is
not permitted to fully empty between pump strokes. The reusable portion
or the dispensing chamber membrane may include a resilient dispensing
spring (e.g., a spiral shape, a fan shape, or having multiple helical
grooves) positioned atop the dispensing chamber membrane to facilitate
contraction of the dispensing chamber membrane. The control assembly may
include a fluid sensor (e.g., an acoustic volume sensor) in communication
with the dispensing chamber for measuring fluid flow through the
dispensing chamber. An acoustic volume sensor may include a loudspeaker
that can be used by the control assembly for both acoustic volume sensing
and audible alarm generation An acoustic volume sensor may include a
microphone that can be used by the control assembly for both acoustic
volume sensing and monitoring pump operation.
[0036] In still other alternative embodiments, the disposable portion may
include a pump region, and wherein the active mechanical assembly further
includes a pump actuator operating on the pump region. The active
mechanical assembly may include a motor for operation of at least one of
the valve actuator and the pump actuator under control of the control
assembly. The active mechanical assembly may include a plate coupled to
the valve actuator, the pump actuator, and the motor for coordinated
operation of the valve actuator and the pump actuator. The valve region
may be positioned between the reservoir port and the pump region and
operation of the valve actuator and the pump actuator may be coordinated
so as to prevent backflow of fluid toward the reservoir port. The motor
may include one or more shape-memory actuators and may include at least
one pulley for folding a shape-memory actuator to fit within the reusable
portion. The shape-memory actuator may be operated through changes in
heat, and the motor may include a heater for operating the shape-memory
actuator. Alternatively, the shape-memory actuator may be operated
through changes in electrical current passed through at least a portion
of the shape-memory actuator. A shape-memory actuator may be electrically
coupled so as to provide a plurality of electrical paths of different
lengths through the shape-memory actuator for providing different
actuation forces or stroke lengths, and a shorter electrical path may be
used during normal operation of a pump and a longer electrical path may
be used during priming and air-purging of the pump. The motor may include
a plurality of shape-memory actuators. The plurality of shape-memory
actuators may be of the same length/gauge or may be of different
lengths/gauges, and may be used for providing redundant operation of the
active mechanical assembly and/or for providing different actuation
forces or stroke lengths (e.g., a shorter shape-memory actuator used
during normal operation of a pump and a longer shape-memory actuator used
during priming and air-purging of the pump).
[0037] In still further alternative embodiments, the substrate and the
flexible membrane material of the disposable portion may constitute a
fluidic assembly, and the disposable portion may further include a
disposable base into which the fluidic assembly fits. An adhesive pad may
be coupled to a bottom of the disposable base.
[0038] In still other alternative embodiments, the reservoir port may
include a reservoir interface for coupling with a fluid reservoir. The
reservoir interface may include a cannulated needle for introduction into
the fluid reservoir so as to provide fluid communication between the
fluid reservoir and the fluid path or may include a septum for
penetration by a fluid reservoir cannulated needle so as to provide fluid
communication between the fluid reservoir and the fluid path. At least
one of the reusable portion and the disposable portion may include a
recess for receiving a fluid reservoir. The fluid reservoir may be
eccentrically shaped so as to deter incorrect orientation of the fluid
reservoir within the housing.
[0039] In yet more alternative embodiments, the reusable portion and the
disposable portion may include a latching mechanism for permitting
selective engagement and disengagement of the reusable and disposable
portions. The reusable portion may include at least one latch actuator
for permitting selective coupling and decoupling of the reusable and
disposable portions.
[0040] In other alternative embodiments, the control assembly may include
an electrical power source for providing electrical power to electronics
in at least one of the reusable portion and the disposable portion. The
electrical power source may include a rechargeable battery. The control
assembly further may further include a battery recharging circuit for
recharging a battery, and may also include a coil for inductively
coupling the battery recharging circuit with an external power source for
recharging the rechargeable battery. The control assembly may also
include a backup electrical power source, such as a battery or a
supercapacitor. Additionally or alternatively, the disposable portion may
include an electrical power source, such as a battery or supercapacitor,
for providing electrical power to electronics in at least one of the
reusable portion and the disposable portion.
[0041] In still other alternative embodiments, the control assembly may
include a network interface, such as a wireless transceiver and/or a
wireline interface, for communication with a remote controller. With
regard to a wireless transceiver, the control assembly may include a coil
coupled to the wireless transceiver for conveying radio frequency signals
to and from the wireless transceiver. The control assembly may also
include a battery recharging circuit for recharging a rechargeable
battery, wherein the coil is further coupled to the battery recharging
circuit for inductively coupling the battery recharging circuit with an
external power source. The control assembly may receive configuration
information from the remote controller and send status information to the
remote controller via the network interface.
[0042] In yet other alternative embodiments, various types of input/output
devices and sensors, such as an audible output (e.g., a speaker), a
visual output (e.g., an LED), a tactile output (e.g., a vibrating
mechanism), a wireless output, an audio input (e.g., a microphone),
and/or a temperature sensor (e.g., for sensing fluid, AVS, skin, or
ambient temperature) may be disposed in the reusable portion and/or the
disposable portion for audible alarm generation. The reusable portion
and/or the disposable portion may be configured to generate an alarm to
alert the user or a third party to an indicate such things as an
operational condition (e.g., power on condition, proper operation of the
control assembly, or proper delivery of fluid within a predetermined set
of parameters) and a fault condition (e.g., a low power level, a low
fluid level, an abnormal temperature level, a problem with a primary or
backup power supply, detection of an occlusion, detection of an air
bubble, detection of a fluid leak, decoupling of the reusable portion and
the disposable portion, communication failure between the reusable
portion and the disposable portion, expiration of the disposable portion,
attempted re-use of the disposable portion, detection of abnormal
vibration from the pump, or detection of lack of vibration from the
pump). The disposable portion may include a processor for at least one of
continuing device operation in the event of a failure, generating an
alarm to indicate that a failure has occurred, and providing status
information to the control assembly (e.g., operational history of the
disposable portion, characteristics of the disposable portion (e.g.,
manufacturer, model number, serial number), or usage information (e.g.,
shelf life, maximum exposure, maximum operation temperature, expiration
date, safe dispensing limits for the therapeutic). The control assembly
may be configured to selectively prevent operation of the active
mechanical assembly and generate an alarm based on status information
received from the processor.
[0043] In additional embodiments, the control assembly may include a user
input, operable from outside of the housing, for actuating the mechanical
assembly to deliver a predetermined quantity of fluid. The predetermined
quantity may be programmable, e.g., from a remote controller, and may be
delivered as a single bolus or a plurality of pulses. The user input may
include a manual control, accessible from outside of the housing, for
manual actuation of the mechanical assembly. Additionally or
alternatively, the user input may include a network interface for remote
actuation of the mechanical assembly from a remote controller. The
control assembly may be configured to generate an alert (e.g., audible
alert, a visual alert, a tactile alert, or a query provided from a remote
controller) upon attempted actuation of the mechanical assembly via the
user input and to require a user confirmation before actuating the
mechanical assembly to deliver the predetermined quantity of fluid. The
control assembly may be configured to generate an alert after completing
delivery of the predetermined quantity of fluid.
[0044] In further additional embodiments, the disposable portion may be
configured to support a cannulus in fluid communication with the fluid
path and an analyte sensor in communication with the control assembly.
Interconnection between the control assembly and the analyte sensor may
be established upon engagement of the reusable portion and the disposable
portion. The control assembly may include an analyte sensor interface for
direct interconnection with the analyte sensor.
[0045] In still further additional embodiments, at least one pad may be
situated between an underside of the disposable portion and a patient's
skin so as to provide separation between the disposable portion and a
patent's skin. The at least one pad may be secured to the underside of
the disposable portion and/or may include adhesive for securing the
disposable portion to the patient's skin. Alternatively, the at least one
pad may be placed loosely between the underside of the disposable portion
and the patient's skin. The at least one pad may be configured to provide
for air flow to a portion of the patient's skin covered by the disposable
portion when placed on the patient. For example, air flow may be provided
by at least one of passageways through the pad, passageways between pads,
and construction of the at least one pad from a porous material.
[0046] In still more additional embodiments, the housing may be affixed to
a human body using an adhesion system including a first set of three or
more members, each member including an adhesive material on at least one
side so as to attach to the body upon application of pressure, the
members disposed around a central region; and a second set of three or
more members, each member including an adhesive material on at least one
side so as to attach to the body upon application of pressure, the
members disposed around the central region, wherein the members of the
first set are spaced to allow the members of the second set to attach to
the body in spaces provided between the members of the first set, and
wherein the members of the second set spaced to allow members of the
first set to detach from the body without detaching the members of the
second set. At least one member may be perforated so as to allow facile
tearing off of the member. At least one peelable backing strip may also
be provided. Members of the first set may be a first color and the
members of the second set may be a second color different from the first
color.
[0047] In further embodiments, the housing may be secured using a
plurality of tethers coupled to the housing and a plurality of adhesive
members for securing the tethers to a patient's skin.
[0048] In accordance with another aspect of the invention there is
provided a disposable unit for a patch-sized fluid delivery device, the
disposable unit removably engageable with a corresponding reusable unit,
the disposable unit including a substrate having flexible membrane
material thereon and incorporating therein a fluid channel, the fluid
channel being part of a fluid path in the disposable unit from a
reservoir port to a cannula port and including a series of regions
exposed to the flexible membrane material, at least one of such regions
being a valve region, so that an active mechanical assembly in the
resusable portion can interact mechanically with the regions through the
membrane material in such a manner as to achieve pumping of fluid along
the fluid path, the active mechanical assembly including a valve actuator
operating on the valve region.
[0049] In various alternative embodiments, the series of regions may be
exposed to a single flexible membrane of the flexible membrane material.
A fluid impedance may be included in the fluid path downstream of the
regions to as to prevent pumping of fluid along the fluid path at an
unsafe flow rate. Such a fluid impedance may include at least one of a
tortuous conduit that is an integral part of the fluid channel and tubing
that is in fluid communication with the fluid channel. The substrate may
include a dispensing chamber formed in the fluid channel of the
substrate, such chamber bounded by flexible membrane material forming a
dispensing chamber membrane. The dispensing chamber membrane may include
a resilient dispensing spring to facilitate contraction of the dispensing
chamber membrane. The series of regions may also include a pump region
for operation by a corresponding pump actuator in the reusable unit
through the flexible membrane material. The substrate and the flexible
membrane material may constitute a fluidic assembly, and the disposable
unit may include a disposable base into which the fluidic assembly fits.
An adhesive pad may be coupled to a bottom of the disposable base. The
reservoir port may include a reservoir interface for coupling with a
fluid reservoir, the reservoir port including one of a needle for
introduction into the fluid reservoir and a septum for penetration by a
fluid reservoir needle so as to provide fluid communication between the
fluid reservoir and the fluid path. A latching mechanism may be provided
for permitting selective engagement and disengagement with the reusable
unit. An electrical power source may be included for providing electrical
power to electronics in at least one of the reusable unit and the
disposable unit. At least one output selected from the group consisting
of an audible output, a visual output, a tactile output, and a wireless
output may be included. The disposable unit may be configured for at
least one of inserting and supporting a cannulus for fluid communication
with the fluid path and an analyte sensor for communication with a
control assembly of the reusable unit. The disposable unit may include a
mechanism for attaching the disposable unit to a patient. The disposable
unit may include a processor for at least one of continuing device
operation in the event of a failure, generating an alarm to indicate that
a failure has occurred, and providing status information to the reusable
portion.
[0050] In accordance with another aspect of the invention there is
provided a reusable unit for a patch-sized fluid delivery device, the
reusable unit removably engageable with a corresponding disposable unit
including a substrate having a flexible material thereon and
incorporating a fluid channel, the reusable unit including a control
assembly having an active mechanical assembly that interacts mechanically
with regions of the fluid channel in the substrate, including a valve
region, through the flexible membrane material in such a manner as to
achieve pumping of fluid along a fluid path including the fluid channel,
the active mechanical assembly including a valve actuator for operating
on the valve region.
[0051] In various alternative embodiments, the disposable unit may include
a dispensing chamber bounded by flexible membrane material, and the
reusable unit may include a fluid sensor for communication with the
dispensing chamber for measuring fluid flow through the dispensing
chamber. A resilient dispensing spring may be provided to facilitate
contraction of the dispensing chamber membrane. The fluid sensor may be
an acoustic volume sensor. The acoustic volume sensor may include a
loudspeaker, and the loudspeaker may be used by the control assembly for
both acoustic volume sensing and audible alarm generation. The acoustic
volume sensor may include a microphone, and the microphone may be used by
the control assembly for both acoustic volume sensing and monitoring pump
operation. The reusable unit may include a pump actuator for operating on
a pump region of the disposable unit through flexible membrane material.
The active mechanical assembly may include a motor for operation of at
least one of the valve actuator and the pump actuator under control of
the control assembly, the motor including at least one shape-memory
actuator. The reusable unit may include a latching mechanism for
permitting selective engagement and disengagement with the disposable
unit. The control assembly may include at least one electrical power
source for providing electrical power to electronics in at least one of
the reusable unit and the disposable unit. The control assembly may
include a battery recharging circuit for recharging a battery and a
mechanism (e.g., a coil) for providing electrical power to the battery
recharging circuit. The control assembly may include a network interface
for communication with a remote controller. The control assembly may
include at least one alarm output selected from the group consisting of
an audible output, a visual output, a tactile output, and a wireless
output. The control assembly may include a temperature sensor. The
control assembly may include a user input for user actuation of the
mechanical assembly to deliver a predetermined quantity of fluid. The
control assembly may be configured to selectively prevent operation of
the active mechanical assembly and generate an alarm based on a status of
the disposable portion.
[0052] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing and an active
mechanical assembly disposed within the housing, the active mechanical
assembly including a mechanical pump and a motor for operation of the
mechanical pump, the motor including a plurality of actuators, each
capable of operating the pump independently of the other actuators so as
to provide for redundancy in the event of failure an actuator.
[0053] In various alternative embodiments, the motor may include one or
more shape-memory actuators and may include at least one pulley for
folding a shape-memory actuator to fit within the reusable portion. The
shape-memory actuator may be operated through changes in heat, and the
motor may include a heater for operating the shape-memory actuator.
Alternatively, the shape-memory actuator may be operated through changes
in electrical current passed through at least a portion of the
shape-memory actuator. A shape-memory actuator may be electrically
coupled so as to provide a plurality of electrical paths of different
lengths through the shape-memory actuator for providing different
actuation forces or stroke lengths, and a shorter electrical path may be
used during normal operation of a pump and a longer electrical path may
be used during priming and air-purging of the pump. The motor may include
a plurality of shape-memory actuators. The plurality of shape-memory
actuators may be of the same length/gauge or may be of different
lengths/gauges, and may be used for providing redundant operation of the
active mechanical assembly and/or for providing different actuation
forces or stroke lengths (e.g., a shorter shape-memory actuator used
during normal operation of a pump and a longer shape-memory actuator used
during priming and air-purging of the pump).
[0054] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing enclosing a fluid
delivery assembly and a plurality of electrical power sources for
providing electrical power to the fluid delivery assembly. The housing
may include a reusable portion and a disposable portion that is removably
engageable with the reusable portion, and the plurality of electrical
power sources are disposed solely in the reusable portion, solely in the
disposable portion, or in both the reusable portion and the disposable
portion. The plurality of electrical power sources may include a primary
electrical power source and a backup electrical power source. The primary
electrical power source may be a rechargeable battery, and the backup
electrical power source may be one of a battery and a supercapacitor.
[0055] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing enclosing a fluid
delivery system, the fluid delivery system including a controller and a
plurality of outputs in communication with the controller, the controller
operably coupled generate an alarm through actuation of the plurality of
outputs.
[0056] In various alternative embodiments, the plurality of outputs may be
selected from the group consisting of an audible output, a visual output,
a tactile output, and a wireless output. The alarm may be used to
indicate at least one of an operational condition (e.g., power on
condition, proper operation of the control assembly, or proper delivery
of fluid within a predetermined set of parameters) and a fault condition
(e.g., a low power level, a low fluid level, an abnormal temperature
level, a problem with a primary or backup power supply, detection of an
occlusion in the fluid path, detection of an air bubble in the fluid
path, detection of a fluid leak, decoupling of the reusable portion and
the disposable portion, communication failure between the reusable
portion and the disposable portion, expiration of the disposable portion,
attempted re-use of the disposable portion, detection of abnormal
vibration from the pump, or detection of lack of vibration from the
pump).
[0057] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing including a reusable
portion and a disposable portion that is removably engageable with the
reusable portion, the reusable portion including a control assembly
having an active mechanical assembly for use in pumping fluid along a
fluid path, the disposable portion including at least one attribute
(e.g., operational history of the disposable portion, a characteristic of
the disposable portion, or an attribute for usage of the disposable
portion) discernable by the control assembly, wherein the control
assembly is operably coupled to selectively prevent operation of the
active mechanical assembly and generate an alarm based on the at least
one attribute.
[0058] In various alternative embodiments, the disposable portion may
include a processor for providing attribute information to the control
assembly.
[0059] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing including a reusable
portion and a disposable portion that is removably engageable with the
reusable portion, the reusable portion including a main controller, the
disposable portion including a backup controller capable of at least one
of continuing an operation normally provided by the main controller and
generating an alarm to indicate a failure of the main controller.
[0060] In accordance with another aspect of the invention there is
provided apparatus comprising a patch-sized housing enclosing a fluid
delivery system, the fluid delivery system including a controller and a
user interface in communication with the controller, wherein the
controller is operably coupled to control delivery of fluid to a patient
and to test and report responsiveness of the patient via the user
interface.
[0061] In accordance with another aspect of the invention there is
provided a wearable device for parenteral delivery of fluid, the device
having at least a reservoir, a pump having a motor, and an exit assembly,
and separable reusable and disposable portions, wherein the motor resides
in the disposable portion.
[0062] In various alternative embodiments, all wetted parts may reside in
the disposable portion. The motor may include one or more shape-memory
actuators to convert a source of potential energy (e.g., heat or
electricity) into kinetic energy.
[0063] In accordance with another aspect of the invention there is
provided a system for pumping fluid to a subject. The system includes a
first separable component and a second separable component. The first
separable component includes an inlet fluid path in communication with a
fluid source; a pumping chamber for receiving fluid from the inlet fluid
path; a dispensing chamber for receiving fluid from the pumping chamber;
and an outlet fluid path for carrying fluid from the dispensing chamber
to an exit assembly. The second separable component includes a force
application assembly for compressing the pumping chamber and means for
sensing flow conditions through the line.
[0064] In various alternative embodiments, the force application assembly
may cause flow of fluid to the pumping chamber from the inlet fluid path
to be restricted while urging fluid from the pumping chamber to the
dispensing chamber. The first separable component may include a reservoir
as a fluid source.
[0065] In accordance with another aspect of the invention there is
provided a base sled for holding separable components of a device for
delivery of a therapeutic fluid. The device includes a bottom adapted for
adhesion to the skin of a patient; a fluidic path portion having a
pumping chamber and an outlet; and a groove for securely receiving one or
more of a fluid cannula and a probe cannula. The sled is adapted to
receive a disposable insulin cartridge and a reusable portion.
[0066] In various alternative embodiments, three or more adhesive members
may be provided for adhesive attachment to the skin of the patient. The
members may be disposed around a central region. An attachment means may
be provided for joining the adhesive members to the device. The reusable
portion may include a component selected from the group consisting of: a
flow sensor, an assembly for application of force to the pumping chamber,
a power source, transceiver electronics, a microprocessor, and an alarm.
A mating feature (e.g., a septum or needle) may be provided for the
attachment of a fluid reservoir. Leads may be provided for the
establishment of signal communication between a probe attached to the
probe cannula and the reusable portion.
[0067] In accordance with another aspect of the invention there is
provided an irregularly shaped fluid reservoir adapted for holding a
supply of a therapeutic fluid within a patch-sized housing having a
correspondingly shaped reservoir holding chamber, the fluid reservoir
having a cavity defined by a rigid reservoir body and a flexible
reservoir membrane that is sealingly attached to the rigid reservoir body
around the periphery of the cavity, the flexible reservoir membrane
including at least one portion that collapses as therapeutic fluid is
withdrawn, the irregular shapes of the fluid reservoir and the
corresponding reservoir holding chamber providing for proper orientation
of the fluid reservoir within the reservoir holding chamber.
[0068] In various alternative embodiments, the reservoir may include a
port through which the reservoir can be placed in fluid communication
with a corresponding fluid path in the housing. The port may include a
septum for penetration by a fluid path needle or a needle for
introduction into the fluid path for providing fluid communication
between the reservoir and the fluid path. The port may be seated in a
neck extending from a reservoir body.
[0069] These aspects of the invention are not meant to be exclusive and
other features, aspects, and advantages of the present invention will be
readily apparent to those of ordinary skill in the art when read in
conjunction with the appended claims and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0070] The foregoing features of the invention will be more readily
understood by reference to the following detailed description, taken with
reference to the accompanying drawings, in which:
[0071] FIG. 1 depicts a patient with a patch and a wireless handheld user
interface assembly;
[0072] FIG. 2A is a schematic diagram of a fluid-delivery device with
feedback control;
[0073] FIG. 2B is a schematic diagram of a fluid-delivery device with
feedback control and a reservoir;
[0074] FIG. 3 is a schematic diagram of a fluid-delivery device having an
un-pressurized reservoir;
[0075] FIGS. 4A-4C are schematic sectional diagrams of various embodiments
of a flow restrictor;
[0076] FIG. 5 shows a resilient dispensing assembly in series with a flow
restrictor;
[0077] FIG. 6 shows a dispensing assembly having a metering chamber and a
sensor;
[0078] FIG. 7 shows a dispensing assembly having a metering chamber with a
dispensing spring and a sensor;
[0079] FIG. 8 shows a sectional view of a dispensing assembly with an
alternate acoustic path;
[0080] FIG. 9 shows a schematic view of a dispensing assembly;
[0081] FIG. 10 shows a diaphragm spring for use with a resilient
variable-volume dispensing chamber;
[0082] FIG. 11A shows a kinetic profile of an exemplary basal fluid
delivery;
[0083] FIG. 11B shows a kinetic profile of an exemplary bolus fluid
delivery;
[0084] FIG. 11C shows kinetic data representing a normal fluid delivery;
[0085] FIGS. 11D-11F show kinetic data representing various fault
conditions;
[0086] FIG. 12 shows a flow chart of a sensing and reacting process of an
embodiment of the fluid delivery device;
[0087] FIG. 13 shows a block diagram of a fluidic line with a pressure
generation assembly;
[0088] FIG. 14 shows a block diagram of a fluidic line with a valving
pump;
[0089] FIGS. 15A-15D show schematic diagrams of a pumping mechanism;
[0090] FIG. 16 shows a schematic diagram of a pumping mechanism;
[0091] FIG. 17 schematically shows a sectional view of an embodiment that
includes a shape-memory-wire actuator capable of multiple pumping modes;
[0092] FIG. 18 schematically shows a sectional view of an embodiment that
includes two shape-memory actuators and is capable of multiple pumping
modes;
[0093] FIG. 19 schematically shows a sectional view of an embodiment that
includes shape-memory actuators of differing lengths;
[0094] FIG. 20A-20B schematically show embodiments for attaching a shape
memory actuator;
[0095] FIGS. 21A-21B schematically show embodiments for attaching a shape
memory actuator to a pumping mechanism;
[0096] FIGS. 22 and 23 show pumping mechanisms employing a finger;
[0097] FIG. 24 shows a pumping mechanism employing rotating projections;
[0098] FIG. 25 shows a pumping mechanism employing a plunger and barrel;
[0099] FIG. 26 shows a view of a shape-memory actuator in an expanded
state;
[0100] FIG. 27 shows a view of a shape-memory actuator in a contracted
state;
[0101] FIG. 28 shows a view of a pumping assembly employing a plunger and
barrel, and a shape-memory motor having a lever;
[0102] FIG. 29 shows a view of a pumping assembly employing a plunger and
barrel, and a shape-memory motor;
[0103] FIG. 30 shows a view of a pumping device employing a plunger and
barrel and a shape-memory motor having a wire in a shaft of the plunger;
[0104] FIG. 31 shows a flow line embodiment with a combined pump and
reservoir;
[0105] FIG. 32 schematically shows a sectional view of a valving pump in a
resting position;
[0106] FIG. 33 schematically shows a sectional view of the valving pump of
FIG. 32 in an intermediate position;
[0107] FIG. 34 schematically shows a sectional view of the valving pump of
FIG. 32 in an actuated position;
[0108] FIG. 35 schematically shows a sectional view of a pumping diaphragm
for use in a valving pump;
[0109] FIG. 36 shows a perspective view of a diaphragm spring for use in a
pumping diaphragm;
[0110] FIG. 37 schematically shows a sectional view of a valving pump
employing a lever and a shape memory wire actuator;
[0111] FIG. 38 schematically shows a sectional view of an embodiment that
includes a valving pump which employs a resilient cylindrical flexure;
[0112] FIG. 39 schematically shows a sectional view of an embodiment that
includes a valving pump flexure having a resilient member and a rigid
support;
[0113] FIG. 40 schematically shows a sectional view of a valving pump, in
a resting state, with a diaphragm spring upstream of a flexible membrane;
[0114] FIG. 41 schematically shows a sectional view of the valving-pump of
FIG. 40, in an intermediate state;
[0115] FIG. 42 schematically shows a sectional view of the valving-pump of
FIG. 40, in an actuated state;
[0116] FIG. 43 schematically shows a sectional view of a valving-pump with
a diaphragm spring upstream of a flexible membrane, in which a flexible
membrane is circumferentially attached to a force application member;
[0117] FIG. 44 schematically shows a sectional view of a valving-pump with
a diaphragm spring upstream of a flexible membrane, which includes a
rigid ball for transmitting force;
[0118] FIG. 45 schematically shows a sectional view of an embodiment that
includes a valving pump having a resilient pump blade;
[0119] FIG. 46 schematically shows a sectional view of an embodiment that
includes an alternative version of a resilient pump blade for use with a
valving pump;
[0120] FIG. 47 schematically shows a sectional view of an embodiment that
includes a valving pump having multiple force application members;
[0121] FIG. 48 schematically shows, in a resting or filling mode, a
pumping mechanism including a bell-crank driven valving-pump and a
flow-biasing valve;
[0122] FIG. 49 schematically shows the pumping mechanism of FIG. 48 in an
actuated state.
[0123] FIG. 50 schematically shows a sectional view of a flow-biasing
valve in accordance with an embodiment of the invention having a raised
valve seat and in a closed position;
[0124] FIG. 51 schematically shows a sectional view of the flow-biasing
valve of FIG. 50 in an open position;
[0125] FIG. 52 schematically shows a sectional view of a flow-biasing
valve in accordance with an embodiment of the invention without a raised
valve seat and in an open position;
[0126] FIG. 53 schematically shows a sectional view of the flow-biasing
valve of FIG. 52, in a closed position;
[0127] FIG. 54 schematically shows forces that act upon a poppet in the
vicinity of a valve outlet in accordance with embodiments of the
invention;
[0128] FIG. 55 schematically shows, in close-up view, forces that act upon
a poppet in the vicinity of a valve inlet in accordance with embodiments
of the invention;
[0129] FIG. 56 schematically shows a flow-biasing valve with an adjustable
cracking pressure in accordance with an embodiment of the invention;
[0130] FIGS. 57 and 58 show schematics for flow lines utilizing
un-pressurized reservoirs;
[0131] FIGS. 59A-59E shows schematics of a fluid flow in a fluid delivery
device;
[0132] FIGS. 60A-60D shows exploded schematics of the fluid flow in a
fluid delivery device;
[0133] FIGS. 61A-61C show schematics of a fluid flow in a fluid delivery
device;
[0134] FIGS. 62A and 62B show schematics of a stand alone device;
[0135] FIGS. 63A-63C show cross sectional schematics of embodiments of a
device;
[0136] FIGS. 64A-64D show cross section schematics of embodiments of a
device;
[0137] FIGS. 65A-65B show cross section schematics of embodiments of an
infusion device connected to a fluid line;
[0138] FIGS. 66A-66D show cross section schematics of a sequence of
inserting a reservoir into a device;
[0139] FIGS. 67A-67F show schematics of embodiments of the fluid delivery
device;
[0140] FIG. 68 is schematic of one embodiment of the portable pump
embodiment of the device connected to a patient;
[0141] FIGS. 69A-69B show schematic views of the underside of the housing
of a device;
[0142] FIGS. 70-70D are a diagram depicting the various components
available in embodiments of the fluid delivery device;
[0143] FIG. 71 schematically shows components which may be assembled to
create a fluid delivery device in accordance with an embodiment of the
device;
[0144] FIG. 72 shows a side view of a fluid-delivery device with an
acoustic volume-measurement component;
[0145] FIG. 73 shows a printed circuit board for acoustic volume
measurement;
[0146] FIG. 74 shows a pictorial view of an embodiment of a device;
[0147] FIG. 75 shows a pictorial sectional view of an embodiment of fluid
delivery device;
[0148] FIG. 76 shows an exploded pictorial view of an embodiment of a
fluid delivery device;
[0149] FIG. 77 shows an exploded view of components which may be assembled
to create one embodiment of a fluid delivery device;
[0150] FIG. 78 shows an exploded view of an embodiment of the fluid
delivery device;
[0151] FIG. 79 shows a top view of a base of one embodiment of the fluid
delivery device;
[0152] FIG. 80 shows the underside of the top of one embodiment of the
fluid delivery device;
[0153] FIGS. 81A-81C show a sequence to illustrate the process of
sandwiching the reservoir 20 between the top and base;
[0154] FIG. 82 shows an exploded top view of a device;
[0155] FIG. 83 shows an exploded view of the bottom of one embodiment of
the device showing the fluid path assembly, the bottom housing and the
membrane and adhesive;
[0156] FIG. 84 shows a bottom view of the base showing a bottom view of a
fluid path assembly;
[0157] FIGS. 85A-85D show exploded, partially exploded and non-exploded
views of an embodiment of a device;
[0158] FIG. 86A shows a schematic of an infusion and sensor assembly
having an infusion device and analyte sensor connected;
[0159] FIG. 86B shows an exploded view of an infusion and sensor assembly
as shown in FIG. 86A with introduction needles;
[0160] FIGS. 87A-87E shows a sequence of an embodiment of the infusion and
sensor assembly being inserted into a device;
[0161] FIGS. 88A-88B show one embodiment of an inserter device in a
sequence with an infusion and sensor assembly;
[0162] FIGS. 88C-88D show a partial cut away view of the inserter in FIG.
88A-88B;
[0163] FIG. 89A shows a front view of one embodiment of an inserter device
for the insertion of an infusion and sensor assembly;
[0164] FIG. 89B shows a rear view of insertion device of FIG. 89A;
[0165] FIG. 90 shows a perspective view of one embodiment of a cartridge
for an infusion and sensor assembly;
[0166] FIGS. 91A-91C show perspective front and side views of an inserter
device for insertion of infusion and sensor assembly;
[0167] FIGS. 92A-92F schematically shows a temporal sequence for the
operation of one embodiment of an inserter mechanism;
[0168] FIG. 92G shows an inserter mechanism having a catch and a cocking
lever in a closed position;
[0169] FIG. 92H shows an inserter mechanism with a catch and a cocking
lever in an open position;
[0170] FIGS. 93A-93C show a time-series for the insertion of a cannula
into a base of a fluid delivery device;
[0171] FIGS. 94A-94C shows a temporal sequence for the insertion of a
cannula into a base with co-incident connection of the cannula to a fluid
line;
[0172] FIG. 95 shows a top view of an adhesive patch for holding a fluid
delivery device;
[0173] FIG. 96 schematically shows a sectional view of a fluid-delivery
device under an adhesive patch;
[0174] FIG. 97 shows a perspective view of two overlapping adhesive
patches for holding a fluid delivery device;
[0175] FIG. 98 shows a top view of two semicircular adhesive patch
portions;
[0176] FIG. 99 shows a perspective view of two semicircular adhesive patch
portions holding a fluid delivery device;
[0177] FIG. 100 shows a perspective view of a semicircular adhesive patch
portion being removed by a patient;
[0178] FIG. 101 shows a perspective view of a fluid-delivery device being
held against a patient using multiple adhesive members and tethers;
[0179] FIG. 102A shows a clamp for assembling a device;
[0180] FIG. 102B shows a base of a fluid delivery device having keyholes
for inserting clamps;
[0181] FIG. 102C shows a sectional view of a fluid delivery device
assembled with a clamp;
[0182] FIG. 103A shows a perspective view of a cam guide for use in
assembling a fluid delivery device;
[0183] FIG. 103B shows a top view of the cam guide of FIG. 103A;
[0184] FIG. 103C shows a perspective view of a clamp pin for use in
assembling a fluid delivery device;
[0185] FIG. 103D shows an embodiment of a fluid delivery device assembled
using a clamp pin and cam guide;
[0186] FIG. 104 shows a sectional view of a collapsible reservoir in
accordance with one embodiment;
[0187] FIG. 105 shows a perspective view the reservoir of FIG. 104;
[0188] FIG. 106A-106C shows a series of steps for securing a septum to a
cap to produce a reservoir in accordance with one embodiment;
[0189] FIG. 107 shows a reservoir filling station in accordance with one
embodiment;
[0190] FIGS. 108A-108B shows an embodiment of a reservoir filling station
in both the open (108A) an closed (108B) positions;
[0191] FIG. 109A shows a block diagram of one embodiment of a data
acquisition and control scheme for an embodiment of the fluid delivery
system;
[0192] FIG. 109B shows a block diagram of one embodiment of a data
acquisition and control scheme for an embodiment of the fluid delivery
system FIG. 110A shows a flow chart describing the operation of a fluid
delivery device according to one embodiment;
[0193] FIG. 110B shows a flow chart describing the operation of a fluid
delivery device according to one embodiment;
[0194] FIG. 111 shows a block diagram of a user interface and fluid
delivery component in wireless communication with each other;
[0195] FIG. 112 shows a data flow diagram showing the use of an
intermediate transceiver in accordance with one embodiment;
[0196] FIG. 113 shows a block diagram for an intermediate transceiver in
accordance with one embodiment;
[0197] FIG. 114 shows a data flow diagram for a universal patient
interface in accordance with one embodiment;
[0198] FIG. 115 shows a non-disposable portion of the fluid delivery
device and a battery recharger in an uncoupled state in accordance with
one embodiment;
[0199] FIG. 116 shows the non-disposable portion of the fluid delivery
device and battery recharger of FIG. 115 in a docked state in accordance
with one embodiment; and
[0200] FIG. 117 is a flowchart depicting a process for measuring the
volume of liquid delivered in a pump stroke, in accordance with an
embodiment of the invention.
[0201] It should be noted that the foregoing figures and the elements
depicted therein are not necessarily drawn to a consistent scale or to
any scale.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS
[0202] Definitions. As used in this description and the accompanying
claims, the following terms shall have the meanings indicated, unless the
context otherwise requires:
[0203] A "user input" of a device includes any mechanism by which a user
of the device or other operator can control a function of the device.
User inputs may include mechanical arrangements (e.g., switches,
pushbuttons), wireless interfaces for communication with a remote
controller (e.g., RF, infrared), acoustic interfaces (e.g., with speech
recognition), computer network interfaces (e.g., USB port), and other
types of interfaces.
[0204] A "button" in the context of a user input such as the so-called
"bolus button" discussed below may be any type of user input capable of
performing a desired function, and is not limited to a pushbutton.
[0205] An "alarm" includes any mechanism by which an alert can be
generated to a user or third party. Alarms may include audible alarms
(e.g., a speaker, a buzzer, a speech generator), visual alarms (e.g., an
LED, an LCD screen), tactile alarms (e.g., a vibrating element), wireless
signals (e.g., a wireless transmission to a remote controller or
caretaker), or other mechanism. Alarms may be generated using multiple
mechanisms simultaneously, concurrently, or in a sequence, including
redundant mechanisms (e.g., two different audio alarms) or complementary
mechanisms (e.g., an audio alarm, a tactile alarm, and a wireless alarm).
[0206] "Fluid" shall mean a substance, a liquid for example, that is
capable of flowing through a flow line.
[0207] "Impedance" shall mean the opposition of a device or flow line to
the flow of fluid therethrough.
[0208] "Wetted" describes a component that comes into direct contact with
the fluid during normal fluid delivery operations. Since a fluid is not
limited to a liquid, a "wetted" component will not necessarily become
wet.
[0209] A "patient" includes a person or animal who receives fluid from a
fluid delivery device, whether as part of a medical treatment or
otherwise.
[0210] "Cannula" shall mean a disposable device capable of infusing fluid
to a patient. A cannula as used herein can refer to a traditional cannula
or to a needle.
[0211] "Analyte sensor" shall mean any sensor capable of determining the
presence of an analyte in a patient. The embodiments of analyte sensors
include, but are not limited to, sensors capable of determining the
presence of any viral, parasitic, bacterial or chemical analyte. The term
analyte includes glucose. An analyte sensor may communicate with other
components within the fluid delivery device (e.g., a controller in a
non-disposable portion) and/or with a remote controller.
[0212] "Dispensing assembly sensor" shall mean a mechanism for determining
the volume of fluid present in the dispensing chamber.
[0213] A "sharp" shall mean anything that is capable of puncturing or
poking an animal's skin, especially a human's skin. A Sharp may include a
cannula, a cannula insertion device, an analyte sensor, or an analyte
sensor insertion device. Sharps may be provided individually or may be
provided together, for example, in a cartridge.
[0214] "Disposable" refers to a part, device, portion or other that is
intended to be used for a fixed duration of time, then discarded and
replaced.
[0215] "Non-disposable" refers to a reusable portion that is intended to
have an open-ended duration of use.
[0216] "Patch-sized" shall mean of a size sufficiently small as to be
secured, by means such as adhesive or straps, to the skin of a patient
and worn as a medical device over a course of administration of substance
contained within the device. A medical device small enough to function as
an implant is within the scope of this definition.
[0217] "Normally present finite fluid impedance" shall mean a finite fluid
impedance that is present in the routine course of fluid delivery, i.e.,
when a fault condition (e.g., an occlusion) is absent.
[0218] A "passive" impedance is one that is not actively controlled during
a pumping cycle.
[0219] "Acoustic volume measurement" shall mean quantitative measurement
of a relevant volume using acoustical techniques such as described in
U.S. Pat. Nos. 5,349,852 and 5,641,892, as well as the techniques
described herein.
[0220] A "temperature sensor" includes any mechanism for measuring
temperature and communicating temperature information to a controller.
The device may include one or more temperature sensors for measuring such
things as skin temperature, AVS temperature, ambient temperature, and
fluid temperatures.
[0221] Embodiments of the device, pumping mechanism, system and methods
described herein relate to fluid delivery including pumping and volume
measurement of fluid as well as the actuation and control of same.
Embodiments of the device include a portable or non-portable device for
fluid delivery. Some embodiments of the device include a base portion
that is disposable and a top portion that is non-disposable. The device
includes embodiments where an infusion device is inserted through the
base portion and directly into a patient. These device embodiments are
patch pump devices. The patch pump may be adhered to the patient using an
adhesive, a strap, or other suitable arrangement. The adhesive may have a
protective peelable strip which may be removed to expose the adhesive
prior to use.
[0222] However, in other embodiments, the fluid delivery device is a
portable device where tubing is connected to a fluid line. The tubing is
typically connected to a patient through a cannula.
[0223] In some embodiments where a disposable base and non-disposable top
are implemented, the base portion includes parts that are wetted, while
the parts included in the non-disposable top portion are typically
non-wetted parts.
[0224] Various embodiments of the pumping mechanism include an upstream
inlet valve, a pumping actuation member, a downstream exit valve and a
moveable member. In some embodiments, the pumping actuation member and
downstream valve functions are implemented using the same device. The
pumping mechanism pumps fluid from a reservoir through a fluid line to an
exit. The pumping mechanism is typically employed with a non-pressurized
reservoir, however, the scope of the present invention is not limited
accordingly.
[0225] In one embodiment of the fluid delivery system, the device includes
an analyte sensor housing. An analyte sensor is introduced into the
patient through the analyte sensor housing of the base portion of the
device. In these embodiments, an infusion device is also introduced
through a cannula housing on the base portion of the device. In these
embodiments, the device is worn by the user as a patch pump.
[0226] The system typically includes a controller, which may include a
wireless transceiver. Thus, the device may be controlled exclusively or
in part through a wireless controller device. The controller device may
receive information through wireless communication from the analyte
sensor and/or the fluid delivery device. The patient or a third party can
control the function of the fluid delivery device using the controller
device.
[0227] In one embodiment of the fluid delivery device, the device is an
insulin pump and the analyte sensor is a blood glucose sensor. The
controller, receiving information relating both to the volume of insulin
delivered (or the number of pump strokes over time) and blood glucose
data, assists the user in programming the actuation schedule for the pump
mechanism.
[0228] An exemplary dispensing assembly and volume sensing device is
described herein. The dispensing assembly includes at least one
microphone and a loudspeaker. The assembly determines the volume change
in a dispensing chamber to determine the volume of fluid pumped. The
volume sensing data is used to determine the status of the fluid delivery
device. Thus, various controls may rely on the volume sensing data.
[0229] In an embodiment of the invention, a user configures the
fluid-delivery device via a user interface in order to cause the
fluid-delivery device to deliver a fluid in an appropriate manner. In one
embodiment, the user interface resides on a separate hand-held
user-interface assembly that may communicate wirelessly with the patch.
The patch may be disposable, or partially disposable.
[0230] An exemplary use of embodiments of the device is for the delivery
of insulin to diabetic patients, but other uses include delivery of any
fluid, as described above. Fluids include analgesics to those in pain,
chemotherapy to cancer patients and enzymes to patients with metabolic
disorders. Various therapeutic fluids may include small molecules,
natural products, peptide, proteins, nucleic acids, carbohydrates,
nanoparticulate suspensions, and associated pharmaceutically acceptable
carrier molecules. Therapeutically active molecules may be modified to
improve stability in the delivery device (e.g., by pegylation of peptides
or proteins). Although illustrative embodiments herein describe
drug-delivery applications, embodiments may be used for other
applications including liquid dispensing of reagents for high throughput
analytical measurements such as lab-on-chip applications and capillary
chromatography. For purposes of description below, terms "therapeutic" or
"fluid" are used interchangeably, however, in other embodiments, any
fluid, as described above, can be used. Thus, the device and description
included herein are not limited to use with therapeutics.
[0231] Typical embodiments include a reservoir for holding a supply of
fluid. In the case of insulin, the reservoir may be conveniently sized to
hold an insulin supply sufficient for delivery over one or more days. For
example, a reservoir may hold about 1 to 2 ml of insulin. A 2 ml insulin
reservoir may correspond to about 3 days supply for about 90% of
potential users. In other embodiments, the reservoir can be any size or
shape and can be adapted to hold any amount of insulin or other fluid. In
some embodiments, the size and shape of the reservoir is related to the
type of fluid the reservoir is adapted to hold. The fluid reservoir may
be eccentrically or irregularly shaped and/or may be keyed in order to
deter incorrect installation or usage.
[0232] Some embodiments of the fluid delivery device are adapted for use
by diabetics, thus, in these embodiments, the device delivers insulin
which supplements or replaces the action of the patient's pancreatic
islet beta cells. Embodiments adapted for insulin delivery seek to mimic
the action of the pancreas by providing both a basal level of fluid
delivery as well as bolus levels of delivery. Basal levels, bolus levels
and timing can be set by the patient or another party by using a wireless
handheld user interface. Additionally, basal and/or bolus levels can be
triggered or adjusted in response to the output of an integral or
external analyte sensor, such as a glucose monitoring device or blood
glucose sensor. In some embodiments, a bolus can be triggered by a
patient or third party using a designated button or other input means
located on the fluid-delivery device. In still other embodiments, the
bolus or basal can be programmed or administered through a user interface
located on the fluid delivery device.
[0233] FIG. 1 shows a patient 12 wearing a fluid-delivery device 10 and
holding a wireless user interface assembly 14 for monitoring and
adjusting operation of the fluid-delivery device 10, in accordance with
an exemplary embodiment of the present invention. The user interface
assembly 14 typically includes apparatus for entering information (such
as touch-screen or keypad) and for transmitting information to the user
(such as an LCD display, a speaker or a vibrating alarm). The fluid
delivery device is typically small and lightweight enough to remain
comfortably adhered to the patient for several days.
[0234] Although the fluid delivery device 10 is shown worn on the arm of a
patient 12 in FIG. 1. In other embodiments, the fluid-delivery device 10
may be worn at other positions on the patient where the particular fluid
being delivered can be utilized advantageously by the patient's body. For
example, fluid may be delivered advantageously to the patient's abdominal
area, kidney area, leg or otherwise.
[0235] Referring now to FIG. 2A, a schematic representation of a fluid
delivery device 10 having a feedback loop 360 from a dispensing assembly
120 to a pumping assembly 16 is shown. The pumping assembly 16 pumps
fluid to the dispensing assembly 120; the fluid then exits through an
exit assembly 17, which includes a flow restrictor 340 and an output. The
output typically includes a cannula and leads to a patient. The
dispensing assembly 120 may include a resilient, variable-volume
dispensing chamber and at least one microphone and a loudspeaker for
measuring parameters related to flow through the output over time. The
feedback loop 360 allows adjustment of the operation of the pumping
assembly 16 based on repeated measurements made by the sensor. The flow
restrictor 340 creates high impedance between the dispensing assembly 120
and the output of the flow line 5010. The flow restrictor 340 could be,
for example, a section of narrow-bore tubing or microtubing. Referring
now to FIG. 2B, in one embodiment, the pumping assembly 16 pumps fluid
from a reservoir 20 to a dispensing assembly 120.
[0236] Referring now to FIG. 3, a block diagram of a further embodiment
employing fluidic principles is shown. A flow line 310 couples a
reservoir 20, a pumping assembly 16, a dispensing assembly 120, and an
exit assembly 17. The exit assembly 17 may include a high impedance flow
restrictor 340 and an infusion device 5010--for example, a cannula. The
output of the flow restrictor 340 is sent to the infusion device 5010 for
delivery to a patient. The flow restrictor 340 has a higher flow
impedance than that of the portion of the flow line 310 upstream of the
dispensing assembly 120. Therefore, the pumping assembly 16 is capable of
pumping fluid into the dispensing assembly 120 faster than the fluid can
exit the exit assembly 17. The dispensing assembly 120 may include a
variable volume dispensing chamber 122 having a resilient wall. In
embodiments presented below, the resilient wall is a membrane. Examples
of membrane materials include silicone, NITRILE, and any other material
having desired resilience and properties for functioning as described
herein. Additionally, other structures could serve the same purpose. Upon
receiving a charge of fluid as a result of the action of the pumping
assembly 16, the resilience of the membrane will allow the chamber 122 to
first expand and then to provide the delivery pressure required to drive
the fluid contents of the dispensing assembly 120 past the flow
restrictor 340 to a patient. When equipped with an appropriate sensor
(examples of which are described below), the dispensing assembly 120 may
measure fluid flow through the variable volume dispensing chamber 122 and
may provide feedback through the feedback loop 360 to control the timing
and/or rate at which the pumping assembly 16 pumps or partially fills the
dispensing chamber 122, thereby delivering a desired dose at a desired
rate to a patient.
[0237] Referring again to FIG. 3, additionally, the flow restrictor 340
prevents fluid flow above a specified flow rate. Furthermore, since
pressurized fluid delivery is accomplished through the interaction of the
pumping assembly 16, the dispensing assembly 120, and the flow restrictor
340, a non pressurized reservoir 20 can be employed.
[0238] Still referring to FIG. 3, the feedback loop 360 may include a
controller 501. The controller 501 may include a processor and control
circuitry for actuating a pumping assembly 16 to pump fluid to the
dispensing assembly 120. The controller 501 repeatedly receives a
parameter related to fluid flow from a sensor, which may be integral to
the dispensing assembly 120, and uses this parameter to control the
pumping assembly 16 to achieve a desired flow through the output. For
example, the controller 501 can adjust the timing or extent of actuation
of the pumping assembly 16 to achieve a desired basal or bolus flow rate
and/or to deliver a desired basal or bolus cumulative dose. In
determining the timing or extent of pumping, the controller 501 may use
the output of the sensor (not shown) to estimate (amongst other things)
the rate of fluid flow, cumulative fluid flow, or both, and then, based
on the estimation, determine an appropriate compensatory action. In the
various embodiments, pumping may occur in pulses which can deliver
anywhere between 10.sup.-9 liters per pulse to microliters per pulse. A
basal or bolus dose may be achieved by delivering multiple pulses.
(Examples of basal and bolus dosing are shown and described below).
[0239] The use of a partially collapsible non pressurized reservoir 20 may
advantageously prevent the buildup of air in the reservoir as the fluid
in the reservoir is depleted. The reservoir 20 may be connected to the
fluid line 310 through a septum (not shown). Air buildup in a vented
reservoir could prevent fluid egress from the reservoir 20, especially if
the system is tilted so that an air pocket intervenes between the fluid
contained in the reservoir and the septum of the reservoir 20. Tilting of
the system is expected during normal operation as a wearable device.
FIGS. 104-106C depict various embodiments and views of one embodiment of
the reservoir. Additionally, further description of the reservoir is
included below.
[0240] Referring now to FIGS. 4A-4C, various embodiments of the flow
restrictor 340 are shown. Referring now to FIG. 4A, the flow restrictor
is a molded flow channel 340, which may be a molded groove in a base (not
shown). In one embodiment, the cross section of the molded flow channel
340 is approximately 0.009 inches. In this embodiment, the flow
restrictor 340 is molded into an apparatus. Referring now to FIG. 4B,
microtubing 340 is shown as an alternate embodiment flow restrictor. In
one embodiment, the microtubing has an internal diameter of approximately
0.009 inches. Both the molded flow channel and the microtubing use a long
path having a small internal diameter or cross section to impart flow
impendence. Referring now to FIG. 4C, a precision orifice is shown as a
flow restrictor 340. In one embodiment, the precision orifice is a plate
with a laser drilled hole. In alternate embodiments, any flow impendence
device or method known in the art can be used.
[0241] In contrast to prior-art fluid delivery systems that have an active
downstream valve, which may be generally considered to create, in a
functional sense, an infinite fluid impedance, the flow restrictor 340
creates a finite fluid impedance. The impedance is also normally present;
in contrast to prior-art systems than may occasionally be impeded due to
an occlusion. As a result of the finite nature of the fluid impedance, in
embodiments that include a dispensing chamber 122, fluid may leak through
the exit even while the dispensing chamber 122 is expanding.
[0242] FIGS. 5-8 schematically show sectional views of illustrative
embodiments of the dispensing assembly 120. It is to be understood that
the delivery of fluid for other purposes, such as industrial processes,
is within the scope of the present invention, and that the description in
particular terms is by way of example only. As shown in FIG. 5, the
dispensing assembly 120 may include the variable volume dispensing
chamber 122 and a sensor 550. The variable volume dispensing chamber 122
includes a resilient dispensing diaphragm 125, which allows the chamber
122 to expand and contract depending on the flow of fluid into and out of
the dispensing assembly 120. In certain embodiments of the invention, the
variable-volume dispensing chamber 122 may be detachable from other
elements of the dispensing assembly 120, as further discussed herein. The
concept of the resilient dispensing diaphragm 125 allowing the chamber
122 to expand and contract is illustrated by the double headed arrow.
Metering chamber 122 is considered to comprise a portion of a line 110
characterized by a fluid flow, which is designated, in FIG. 5, by arrow
112. Neither the position nor the nature of the termination of fluid flow
112 or line 110 need limit the scope of the present invention as claimed
in certain of the claims appended hereto. The flow restrictor 340 causes
fluid to leave the dispensing chamber 122 more slowly than fluid enters
the chamber 122 when pumped into the chamber 122 by the pumping assembly
16. As a consequence, the dispensing chamber 122 expands and is
pressurized as a fluid charge enters. Dispensing diaphragm 125, deformed
by virtue of the expansion of dispensing chamber 122, provides the force
needed to deliver the metered volume past the flow restrictor 340 to the
exit assembly 17. As discussed above, the sensor 550 repeatedly measures
a parameter, such as a displacement, or a thermodynamic variable or
capacitance, that can be related to the volume of the resilient
dispensing chamber 122. The volume measurements produced by the sensor
550 may be used to control, through a feedback loop, the timing and rate
at which the pumping assembly pumps fluid to the dispensing chamber 122
so that the proper flow of fluid is delivered to exit assembly 17 and to
a subsequent line, and thence, for example, to the patient. The sensor
550 may employ, for example, acoustic volume sensing (described in more
detail below), or other methods (optical, or capacitive, for other
examples) for determining a volume, or a volume-related parameter.
Acoustic volume measurement technology is the subject of U.S. Pat. Nos.
5,575,310 and 5,755,683 assigned to DEKA Products Limited Partnership, as
well as the co-pending provisional U.S. patent application entitled
"METHOD OF VOLUME MEASUREMENT FOR FLOW CONTROL", Ser. No. 60/789,243,
filed Apr. 5, 2006, all of which are hereby incorporated herein by
reference. Fluid volume sensing in the nanoliter range is possible with
this embodiment, thus contributing to highly accurate and precise
monitoring and delivery. Other alternate techniques for measuring fluid
flow may also be used; for example, Doppler-based methods; the use of
Hall-effect sensors in combination with a vane or flapper valve; the use
of a strain beam (for example, related to a flexible member over a fluid
chamber to sense deflection of the flexible member); the use of
capacitive sensing with plates; or thermal time of flight methods.
[0243] Referring now to FIGS. 6 through 9, embodiments are shown in which
a sensor utilizes acoustic volume sensing (AVS) technology. A first
discussion refers to embodiments depicted in FIGS. 6 and 7. The
dispensing assembly 120 has a sensor that includes a reference chamber
127, and a variable volume measurement chamber 121 that is coupled by a
port 128 to a fixed-volume chamber 129. While the invention may be
practiced with a reference chamber 127, as shown in FIGS. 6 and 7, in
certain other embodiments of the invention, no reference volume is
provided. It is to be understood that volume 129 is referred to, herein,
as "fixed" as a matter of terminology, but that the actual volume may
vary slightly, on the time scale of acoustic excitation, as when the
region referred to as fixed volume 129 is driven by a speaker diaphragm.
Fluid flows from the pumping assembly 16 to an input 123, through the
resilient dispensing chamber 122, and out of an exit channel 124. Due to
the high downstream impedance, as fluid enters the dispensing chamber
122, the dispensing diaphragm 125 expands into the variable volume
chamber 121. An electronics assembly, which may be arranged on a printed
circuit board 126, has a loudspeaker 1202, a sensing microphone 1203, and
a reference microphone 1201 for measuring acoustic parameters associated
with a gas (typically air) in the variable volume chamber 121, the volume
of which is defined by the position of the dispending diaphragm 125.
Sound waves induced by the loudspeaker 134 travel through the fixed
volume chamber 129 to the variable volume chamber 121 via the port 128;
sound waves also travel to the reference chamber 127. As the dispensing
diaphragm 125 moves with the flow of fluid through the flow line, the
volume of air in the variable volume chamber 121 varies, causing related
changes in its acoustic characteristics, which may be detected by the
loudspeaker and microphone 1203. For the same acoustic stimulations, the
reference microphone 1201 may detect acoustic characteristics of the
fixed reference volume 127. These reference measurements may, for
example, be used to factor out imprecision and to reject common-mode
inaccuracies in acoustic stimulation, and other errors. The volume of
fluid displaced may be determined by comparing the measured volume of the
variable volume chamber 121 to an initial volume of the variable volume
chamber 121. Since the total combined volume of the dispensing chamber
122 and variable volume chamber 121 stays constant, the absolute volume
of the dispensing chamber 122 can also be estimated.
[0244] The embodiment shown in FIG. 6 utilizes an inherently resilient
dispensing diaphragm 125, while the embodiment shown in FIG. 7 utilizes a
resilient dispensing spring 130, which when combined with a dispensing
diaphragm 125, increases the resiliency of the dispensing chamber 122 and
may allow the use of a more compliant (i.e., less resilient) dispensing
diaphragm 125 than would be required in the embodiment shown in FIG. 5.
The dispensing spring 130 is typically positioned adjacent to the
dispensing diaphragm 125 on a side of the diaphragm 125 opposite to the
dispensing chamber 122.
[0245] Alternately, to reduce background noise from the microphone, the
loudspeaker 1202 and the sensing microphone 1203 may be coupled to the
variable volume chamber 121 via separate ports. As schematically shown in
FIG. 8, a loudspeaker 1202 generates pressure waves in a fixed
loudspeaker volume 6000 which is acoustically coupled with the variable
volume chamber 121 via a loudspeaker port 6020. Pressure waves travel
from the loudspeaker 1202, through the loudspeaker port 6020 to the
variable volume chamber 121 and then through a microphone port 6010
before being recorded by the sensing microphone 1203. The loudspeaker
port 6020 may include a tube portion 6040 with a flared aperture 6030.
The flared aperture 6030 serves to create a uniform length along which
sound waves travel for all axial paths of the tube portion 6040. For
example, the tube portion 6040 can have the geometry of a cylinder, such
as a right cylinder or right circular cylinder. A similarly flared
aperture may also adjoin a tube portion to define the microphone port
6010. In contrast to the AVS sensor of FIGS. 6 and 7, in the embodiment
of FIG. 8, pressure waves traveling from the loudspeaker 1202 do not have
a direct path to the sensing microphone 1203. Thus, pressure waves from
the loudspeaker 1202 are prevented from directly impacting the sensing
microphone 1203 without first passing through the variable volume 121. A
lower background signal is therefore received by the microphone and a
better signal/noise ratio is achieved. Additionally, an upper shelf 6050
may be included in any of the embodiments of FIGS. 6-8 advantageously
reducing the volume of the reference chamber 127.
[0246] In embodiments to be further described, it may be convenient to
separate the sensor and metering chamber portions of the dispensing
assembly such that the dispensing chamber is detachable and disposable.
In this case, the dispensing chamber resides in a disposable section of
the patch, while the sensor resides in the reusable section. The
dispensing chamber may be bounded by a resilient fluid dispensing
diaphragm (as shown in FIGS. 6 as 122 and 124). Alternately, as in FIG.
7, the dispensing chamber 122 may be bounded by a compliant diaphragm
125. In this case, a dispensing spring 130 can be used to impart
resiliency on the dispensing chamber 122. When the sensor 550 and
dispensing chamber 122 are brought together, the dispensing spring 130
covers the compliant dispensing diaphragm 125. The dispensing spring 130
and dispensing diaphragm 125 may alternately be employed as a single part
defining the dispensing chamber 122.
[0247] As shown in FIG. 9, an alternate embodiment of the dispensing
assembly is shown. In an embodiment of dispensing assembly 120 depicted
in FIG. 9, variable-volume measurement chamber 121 shares a compliant
wall (here shown as compliant diaphragm 125) with dispensing chamber 122.
Port 128 acoustically couples measurement chamber 121 to fixed volume
chamber 129, so as to form an acoustically contiguous region designated
generally by numeral 1290. A compressible fluid (typically, air, or
another gas) fills the acoustically contiguous region 1290 and is excited
by a driving member 1214, itself driven by an actuator 1216. Driving
member 1214 may be a diaphragm of a speaker, such as a hearing aid
speaker, where actuator 1216 is a voice coil solenoid or piezoelectric
element, for example. Within the scope of the invention, driving member
1214 may also be coextensive with actuator 1216, such as where driving
member 1214 may, itself, be a piezoelectric element. Driving member 1214
may be contained within a driver module 1212 that may contain, on a side
of driving member 1214 distal to fixed volume 129, a reference volume
1220. However, reference volume 1220 is typically not employed in
practice of the invention.
[0248] A reference microphone 1208 is shown in acoustic communication with
fixed volume 129, while a signal microphone 1209 is acoustically coupled
to measurement chamber 121. The volume of measurement region 121 may be
determined from electronic signals provided by one or more microphones
1208, 1209 on the basis of pressure variations (or, equivalently,
acoustic signal) measured at their respective positions within the
acoustically contiguous region 1290. Phase measurements may be performed
by comparing the phase of response at one or more microphones relative to
the phase of acoustic excitation or relative to the phase of response at
a position of another microphone. The volume of measurement region 121,
and, by implication, of dispensing chamber 122, is determined, on the
basis of phase and/or amplitude measurements, as discussed below, by a
processor 1210, which derives power from power source 1211, shown,
representatively, as a battery.
[0249] For the purposes of precise delivery of minute amounts of
therapeutic agents, the delivery of small, but very accurately metered,
quantities per pump stroke is desirable. However, if minute volumes of
fluid are to be pumped through line 110 during the course of each pump
stroke, extremely high resolution is required of the metering process.
Consequently, in accordance with embodiments of the present invention,
changes in volume are measured by sensor 550 with a resolution of at
least 10 nanoliters. Measurements of resolution 0.01% of the empty volume
of measurement region 121 may be achieved in some embodiments of the
invention. In accordance with other embodiments of the invention, sensor
550 provides resolution of better than 13 nanoliters. In other
embodiments yet, sensor 550 provides resolution of better than 15
nanoliters, and in yet further embodiments, resolution of better than 20
nanoliters is provided. In such cases, the total volume of acoustically
contiguous region 1290 may be less than 130 .mu.l, and, in other
embodiments, less than 10 .mu.l.
[0250] In accordance with various embodiments of the present invention,
use may be made of a priori modeling of the response of the volume of
dispensing chamber 122, and, consequently of variable-volume chamber 121
(which may also be referred to, herein, as a "metering volume"), based
upon the filling of the dispensing chamber due to a pumped volume of
fluid entering through input 123. While other models are within the scope
of the present invention, one model that may be employed expresses the
volume of fluid within dispensing chamber 122, in response to a pumped
influx of fluid and a outlet of fixed flow impedance, as the sum of a
baseline volume V.sub.B and an exponentially decaying volume
characterized by a peak displacement V.sub.D, such that the metering
chamber volume during a measurement is characterized as a function of
time t, as:
V = V D exp ( - t .tau. ) + V B .
##EQU00001##
[0251] In order to fit a parameterization of the modeled exponential decay
(or other functional model) to a succession of acoustic measurements, the
response of systems such as depicted in FIGS. 6 through 9 is developed as
follows. For purposes of modeling the response, port 128 is characterized
by a length 1 and a diameter d. The pressure and volume of an ideal
adiabatic gas can be related by PV.sup..gamma.=K, where K is a constant
defined by the initial conditions of the system.
[0252] The ideal adiabatic gas law can be written in terms of a mean
pressure, P, and volume, V, and a small time-dependent perturbation on
top of those pressures, p(t), .nu.(t):
(P+p(t))(V+.nu.(t)).sup..gamma.=K.
[0253] Differentiating this equation yields
{dot over
(p)}(t)(V+.nu.(t)).sup..gamma.+.gamma.(V+.nu.(t)).sup..gamma.-1(P+p(t)){d-
ot over (.nu.)}(t)=0
[0254] Or, simplifying,
p . ( t ) + .gamma. P + p ( t ) V + v ( t )
v . ( t ) = 0 ##EQU00002##
[0255] If the acoustic pressure levels are much less than the ambient
pressure the equation can be further simplified to:
p . ( t ) + .gamma. P V v . ( t ) = 0.
##EQU00003##
[0256] Applying the ideal gas law, P=.rho.RT, and substituting in for
pressure gives the result:
p . ( t ) + .gamma. RT .rho. V v . (
t ) = 0. ##EQU00004##
[0257] This can be written in terms of the speed of sound, a= {square root
over (.gamma.RT)}, as:
p . ( t ) + .rho. a 2 V v . ( t ) =
0. ##EQU00005##
[0258] Also, an acoustic impedance for a volume is defined as:
Z v = p ( t ) v . ( t ) = - 1 ( V .rho.
a 2 ) s = - .rho. a 2 V 1 s .
##EQU00006##
[0259] In accordance with one set of models, the acoustic port is modeled
assuming that all of the fluid in the port essentially moves as a rigid
cylinder reciprocating in the axial direction. All of the fluid in the
channel (port 128) is assumed to travel at the same velocity, the channel
is assumed to be of constant cross section, and the "end effects"
resulting from the fluid entering and leaving the channel are neglected.
[0260] Assuming laminar flow friction of the form .DELTA.p=R.rho.{dot over
(.nu.)}, the friction force acting on the mass of fluid in the channel
can be written: F=R.rho.A.sup.2{dot over (x)}.
[0261] A second order differential equation can then be written for the
dynamics of the fluid in the channel:
.mu.LA{umlaut over (x)}=.DELTA.pA-R.rho.A.sup.2{dot over (x)}
or, in terms of volume flow rate:
v = - RA L v . + .DELTA. p A .rho. L
. ##EQU00007##
[0262] The acoustic impedance of the channel can then be written:
Z p = .DELTA. p v . = .rho. L A ( s +
RA L ) . ##EQU00008##
[0263] Using the volume and port dynamics define above, the acoustic
volume sensor system can be described by the following system of
equations (with index k denoting the speaker, and r denoting the
resonator):
p . 0 - .rho. a 2 V 0 v . k = 0.
##EQU00009##
[0264] Following the same convention, {dot over (.nu.)}.sub.k>0{dot
over (p)}1<0 and {dot over (.nu.)}.sub.r>0 {dot over
(p)}.sub.1>0,
p . 1 + .rho. a 2 V 1 ( v . k - v . r
) = 0. ##EQU00010##
[0265] In addition, {dot over (.nu.)}.sub.r>0{dot over (p)}.sub.2<0,
p . 2 + .rho. a 2 V 2 v . r = 0.
##EQU00011##
[0266] The volume tends to accelerate in a positive direction if p.sub.2
is larger than p.sub.1.
v r = - RA L v . r + A .rho. L ( p 2
- p 1 ) . ##EQU00012##
[0267] Reducing the number of equations (treating p.sub.0 as input), and
substituting
v . k = V 0 .rho. a 2 p . 0 , ##EQU00013##
p . 1 + V 0 V 1 p . 0 - .rho. a 2 V 1
v . r = 0 ##EQU00014## p . 2 + .rho. a 2 V
2 v . r = 0 ##EQU00014.2## v r = - RA L v .
r + A .rho. L p 1 - A .rho. L p 2 .
##EQU00014.3##
[0268] This leads to one simple expression using these equations:
.rho. a 2 V 2 v . r = V 1 V 2 (
.rho. a 2 V 1 v . r ) = V 1 V 2 p . 1
+ V 0 V 2 p . 0 ##EQU00015## p . 2 + V 0 V
2 p . 0 + V 1 V 2 p . 1 = 0 ##EQU00015.2##
V 0 p . 0 + V 1 p . 1 = - V 2 p . 2
- V 0 p . 0 + V 1 p . 1 p . 2 = V
2 , or ##EQU00015.3## V 0 p 0 + V 1 p 1 =
- V 2 p 2 - V 0 p 0 + V 1 p 1 p 2
= V 2 ##EQU00015.4##
[0269] These equations can also be expressed in transfer function form.
The "cross-speaker" transfer function, p.sub.1/p.sub.0, is:
s p 1 + V 0 V 1 s p 0 - .rho. a 2 V
1 s v r = 0 ##EQU00016## s p 2 + .rho. a 2
V 2 s v r = 0 ##EQU00016.2## s 2 v r = - RA L
s v r - A .rho. L p 1 + A .rho. L
p 2 ##EQU00016.3## p 2 = - .rho. a 2 V 2 v
r ##EQU00016.4## s 2 v r = - RA L s v r +
A .rho. L ( - .rho. a 2 V 2 ) v r -
A .rho. L p 1 ( s 2 + RA L s + Aa 2 LV 2
) v r = - A .rho. L p 1 v r =
- A / .rho. L s 2 + RA / Ls + Aa 2 /
LV 2 p 1 or p 1 p 0 = - V 0 V 1
s 2 + 2 .zeta..omega. n s + .alpha..omega. n 2 s 2 + 2
.zeta..omega. n s + .omega. n 2 where .omega. n
2 = a 2 A L ( 1 V 1 + 1 V 2 ) ; .zeta. =
RA 2 L .omega. n ; and .alpha. = V 1 V 1
+ V 2 . ##EQU00016.5##
[0270] Similarly, the "cross system" transfer function, based on
measurements on either end of port 128, is p.sub.2/p.sub.0, is given by:
s p 1 + V 0 V 1 s p 0 - .rho. a 2 V
1 s v r = 0 ##EQU00017## s p 2 + .rho. a 2
V 2 s v r = 0 ##EQU00017.2## s 2 v r = - RA L
s v r - A .rho. L p 1 + A .rho. L
p 2 ##EQU00017.3## p 1 = .rho. a 2 V 1 v r
- V 0 V 1 p 0 ##EQU00017.4## s 2 v r = - RA
L s v r - A .rho. L .rho. a 2 V 1
v r - A .rho. L ( - V 0 V 1 p 0 ) +
A .rho. L p 2 v r = AV 0 .rho.
LV 1 s 2 + RA L s + Aa 2 LV 1 p 0 + A .rho.
L s 2 + RA L s + Aa 2 LV 1 p 2 s
p 2 + .rho. a 2 V 2 s [ AV 0 .rho.
LV 1 s 2 + RA L s + Aa 2 LV 1 p 0 + A .rho.
L s 2 + RA L s + Aa 2 LV 1 p 2 ] =
0 [ s 2 + RA L s + Aa 2 LV 1 + Aa 2 LV 2 ]
p 2 = - Aa 2 LV 2 V 0 V 1 p 0 p 2 p
0 = - V 0 V 1 Aa 2 LV 2 s 2 + RA L s +
Aa 2 LV 2 V 1 + V 2 V 1 p 2 p 0 = - V
0 V 1 .alpha..omega. n 2 s 2 + 2 .zeta..omega. n s +
.omega. n 2 ##EQU00017.5##
Volume Estimation Using Cross-System Phase
[0271] Similarly, using the same principles, a transfer function is
readily derived, expressing a pressure in the fixed volume chamber 129 in
terms of the pressure in the variable volume chamber 121 to which it is
coupled via port 128. In particular, the transfer function is:
p 2 p 1 = 1 V 2 L p a 2 A p s 2 +
RV 2 a 2 s + 1 = a 2 A p V 2 L p s 2 +
RV 2 a 2 a 2 A p V 2 L p s + a 2 A p
V 2 L p = .omega. n 2 s 2 + RA p L p s +
.omega. n 2 . ##EQU00018##
[0272] In either of the foregoing cases, the resonant frequency of the
system may be expressed as a function of the variable volume, V.sub.2:
.omega. n 2 = a 2 A L ( 1 V 1 + 1 V 2 ) ,
or 1 V 2 = .omega. n 2 L a 2 A - 1 V 1 .
##EQU00019##
[0273] Since all of the other parameters are known, variable volume
V.sub.2 can be calculated based, for example, on the resonant frequency,
although other methods of deriving V.sub.2 may be advantageous, and are
described further in the course of the present application. The one
parameter that is not a constant in this equation is the speed of sound,
a, which may be calculated, based on a knowledge of the pertinent
temperature, or otherwise derived or measured.
[0274] As stated, various strategies may be employed to interrogate the
system so as to derive volume V.sub.2. In accordance with certain
embodiments of the current invention, the system is excited by driving
member 1214 at a single frequency, while monitoring the response of one
or more transducers (microphones 1208 and 1209, in FIG. 9). The response
is captured as a complex signal, retaining both amplitude and phase of
the pressure variation. It is advantageous that the single interrogating
frequency lie close to the resonance of the system in mid-stroke, since
the largest phase changes with volume over the range of a full to empty
chamber is thereby achieved.
[0275] The response of the signal microphone 1208 may be corrected to
reject common-mode effects due to the frequency-dependent characteristics
of the exciting loudspeaker 1202 (shown in FIG. 6) or driving member 1214
(shown in FIG. 9). The corrected signal, obtained as a complex ratio of
the microphone signals, may be expressed as m.sub.i, where the index i
denotes successive time samples of the signal.
[0276] Expressed, in transfer function form, in analogy, to a second-order
mechanical Helmholtz resonator, the signal may be represented as:
m i .apprxeq. - V 0 V 1 A .gamma.
RT LV 2 s i 2 + .lamda. A L s i + A
.gamma. RT LV 2 V 1 + V 2 V 1 = - V 0 V
1 A .gamma. R L .omega. c 2 T i V 2
.alpha. v , i s i 2 .omega. c 2 + A .lamda.
L .omega. c .lamda. s i .omega. c + A
.gamma. R L .omega. c 2 T i V 1 ( v , i
+ .PSI. 1 , 2 ) v , i = - .kappa. 0 , i
.alpha. v , i s _ i 2 + .psi. 1 s _ i .lamda.
+ .psi. 0 , i .PSI. 1 , 2 + v , i v , i =
- .kappa. 0 , i .alpha. s _ i 2 v , i + .psi. 1
s _ i .lamda. v , i + .psi. 0 , i ( .PSI. 1
, 2 + v , i ) = - .kappa. 0 , i
.alpha. [ .psi. 0 , i ( .PSI. 1 , 2 + v , i ) -
.omega. _ i 2 v , i ] + l .psi. 1 .omega. _ i
.lamda. v , i [ .psi. 0 , i ( .PSI. 1 , 2
+ v , i ) - .omega. _ i 2 v , i ] - l .psi. 1
.omega. _ i .lamda. v , i [ .psi. 0 , i (
.PSI. 1 , 2 + v , i ) - .omega. _ i 2 v , i ]
- l .psi. 1 .omega. _ i .lamda. v , i
= - .kappa. 0 , i .alpha. [ .psi. 0 , i .PSI.
1 , 2 + ( .psi. 0 , i - .omega. _ i 2 ) v , i ]
+ l .kappa. 0 , i .alpha..psi. 1 .omega. _ i
.lamda. v , i [ .psi. 0 , i .PSI. 1 , 2 + (
.psi. 0 , i - .omega. _ i 2 ) v , i ] 2 + .psi. 1 2
.omega. _ i 2 .lamda. 2 v , i 2 ##EQU00020##
[0277] Here, normalization variables have been introduced so as to
maintain relevant parameters within a computationally useful dynamic
range of order unity. The final expression is expressed in terms of the
real and imaginary parts over a common denominator. Taking the ratio of
the real .mu. to the imaginary .nu. parts, (i.e., the phase cotangent),
.mu. i v i .apprxeq. - ( .psi. 0 , i - .omega. _ i 2
) v , i + .psi. 0 , i .PSI. 1 , 2 .psi. 1
.omega. _ i .lamda. v , i , ##EQU00021##
the error may be defined as:
E = 1 M .rho. [ .mu. i D i + v i N i ] 2
, ##EQU00022##
with N and D denoting the numerator and denominator, respectively of the
model.
[0278] If the error is minimized with respect to each of the model
parameters, a best-fit has been achieved. Any method may be employed for
fitting the model parameters. In one embodiment of the invention, a
gradient-descent method is employed to find the minima:
.differential. E .differential. .lamda. = 2 M
.SIGMA..psi. 1 .omega. _ i v , i D i e i
##EQU00023## .differential. E .differential. b = 2 M
.SIGMA. ( .mu. i .differential. D i .differential. b
+ v i .differential. N i .differential. b ) e i
= 2 .SIGMA. ( .mu. i .differential. D i .differential.
v , i + v i .differential. N i .differential. v , i
) e i .differential. v , i .differential. b
##EQU00023.2## .differential. D i .differential. v , i =
.psi. 1 .omega. _ i .lamda. ##EQU00023.3##
.differential. N i .differential. v , i = .psi. 0 , i -
.omega. _ i 2 ##EQU00023.4## .differential. v , i
.differential. b = 1 ##EQU00023.5## .differential. E
.differential. .delta. d = 2 M .SIGMA. ( .mu. i
.differential. D i .differential. v , i + v i
.differential. N i .differential. v , i ) e i
.differential. v , i .differential. .delta. d ##EQU00023.6##
.differential. v , i .differential. .delta. d = exp (
- t i .tau. / .tau. ) ##EQU00023.7##
.differential. E .differential. .tau. = 2 M .SIGMA. (
.mu. i .differential. D i .differential. v , i + v
i .differential. N i .differential. v , i ) e i
.differential. v , i .differential. .tau. ##EQU00024##
.differential. v , i .differential. .tau. = .delta. d
- t i .tau. exp ( - t i .tau. / .tau. ) .
##EQU00024.2##
[0279] The intervals over which each successive temporal sample is
obtained, and the number of intervals sampled in order to fit the
parameters of the temporal model are advantageously optimized for each
specific application of the invention. Where fluid flows at a slow but
relatively constant rate, as in basal insulin delivery, sampling over a
period from .tau./3 to 3.tau. has been found efficacious. On the other
extreme, where a relatively large bolus of fluid is to be delivered, the
fluid may reside in dispensing volume 122 for only a short period of
time, on the time scale of the exponential decay time constant. In that
case, sampling is performed over a shorter fraction of the characteristic
decay time.
[0280] In accordance with preferred embodiments of the invention, volume
of fluid dispensed through dispensing volume 122 is determined on the
basis of a fit to a model of volume vs. time, based on cross-system phase
measurements made at monotonic frequency of excitation. During the
initial portion of a pump stroke, moreover, preliminary measurements are
made in order to calibrate system operation, as now described, in
conjunction with the measurement protocol, with reference to the
flowchart shown in FIG. 117. The metering process, denoted generally by
numeral 1170, advantageously conserves computer resources and minimizes
power consumption, thereby extending the useful time between charges or
replacement of power source 1211 (shown in FIG. 9), while providing,
through frequent calibration, the measurement accuracy required for
delivery of fluid with the resolution per stroke described above.
[0281] Either prior to, or at the beginning 1171 of, each pump stroke, or
both, processor 1210 initiates a Self-Calibration Phase 1172 of the AVS
system. Measurements are held-off until electronic transients due to
activation of the pump have substantially decayed. Microphone and speaker
gains are set, and driving member 1214 is actuated, in step 1173, at a
succession of frequencies, where typically five frequencies are employed,
in the general proximity of the resonance of contiguous acoustic region
1290 (otherwise referred to herein as the "acoustic chamber").
Frequencies in the range of 6-8 kHz are typically employed, though the
use of any frequencies is within the scope of the present invention. At
the onset of activation of each successive frequency, data collection is
delayed, for a period of approximately 5 ms, until acoustic transients
have substantially decayed.
[0282] For a duration of approximately 64 acoustic cycles, data are
collected as follows: the temperature reading provided by temperature
sensor 132 (shown in FIG. 70B) is sampled in step 1174, and the real and
imaginary portions of the ratio of output signals of signal microphone
1209 with respect to reference microphone 1208, denoted .rho. and t,
respectively, are sampled. The complex ratio of signals, or other
functional combination of the microphone signals with respect to the
reference, may be referred to herein as the "signal," for purposes of
describing the AVS system.
[0283] On the basis of measurements at each frequency, taken over the
course of approximately 200 ms per frequency, a set of means and
variances are derived for each of the real and imaginary parts of the
signal at each frequency and for the temperature readings. Analysis, in
step 1175, of these values, permits a determination of whether errors are
within specified bounds. An anomalous transfer function may
advantageously indicate system faults that include, but are not limited
to, faults in the microphones or other sensors, speaker, transducer,
electronics, mechanical components, fluid ingress, poor acoustic seal,
excessive ambient noise, and excessive shock and vibration. Additionally,
the functional dependence of the phase angle of the signal as a function
of frequency is determined in step 1176. The phase angle of the signal,
namely the arctangent of the ratio of imaginary to real portions thereof,
may be used as a measure of phase, however any measure of phase may be
used within the scope of the invention. The functional dependence may be
derived by polynomial fit of the phase to the frequency, or otherwise. On
the basis of the polynomial fit, or otherwise, the slope of phase vs.
frequency is determined at the volume measurement frequency, and volume
measurement proceeds, in step 1177. Additionally, and significantly, an
anomalous slope of phase vs. frequency is indicative of a gaseous bubble
in the fluid contained within dispensing chamber 122.
[0284] For a succeeding portion of each pump stroke, driving member 1214
is actuated at substantially a single frequency, thereby acoustically
exciting the gas within acoustically contiguous region 1290 at that
frequency. Signal data, based typically on the complex ratio of output
signals of signal microphone 1209 with respect to reference microphone
1208 are collected and averaged over specified sampling intervals of
approximately 64 cycles. Real and imaginary components of the signal, as
well as temperature data, are recorded for each sampling interval. Based
on the sampled and collected data, a fit is performed to a temporal
model. In various embodiments of the invention, a gradient-descent method
is employed, as described above, in order to minimize error in fitting
the model parameters, namely the baseline volume V.sub.B, peak
displacement V.sub.D, and decay time .tau., of the variable volume
chamber 121 during the course of each pump stroke, thereby providing the
volume of fluid delivered through dispensing chamber 122.
[0285] Referring now to FIG. 10, the dispensing spring 130 may have a
spiral or fan shape that is complementary to the diaphragm and may have
multiple helical grooves 131. Embodiments of the spring as shown can
apply an approximately even force over the diaphragm. This approximately
even force helps the diaphragm to retain an approximately concave shape
as it expands. The grooves 131 allow air to pass freely through the
spring, thus most air is not trapped between the spring and the
diaphragm.
[0286] Referring now to FIGS. 11A and 11B, examples of kinetic
measurements of the volume of the dispensing chamber 122 (shown in FIG.
5) and of the calculated cumulative volume expelled from the dispensing
chamber 122 are shown for a typical basal delivery pulse (FIG. 11A) and
for a typical bolus delivery (FIG. 11B). As can be seen in FIG. 11A,
actuation of the pumping assembly 16 causes an expansion of the
dispensing chamber 122, as measured by the acoustic volume sensor 550,
from about 0 to about 1.5 .mu.l in about 2 seconds. The resilient
dispensing chamber 122 is seen to contract and expel its fluid from the
chamber 122 through the high impedance output over a course of about 30
seconds with an exponential decay kinetic characterized by a half-life
(t.sub.1/2) of about 6 seconds. The cumulative volume of output from
dispensing chamber 122 is calculated from the measurements made by the
sensor 550 and seen also to rise exponentially to about 1.5 .mu.l. It can
be seen that the high impedance output introduces a delay between
actuation of the pump assembly and delivery of the majority of the
displaced fluid. The t.sub.1/2 characteristic of the system can be chosen
with attention to the resilient force exerted by the dispensing chamber
122 and the degree of impedance of the output. In various embodiments,
the time constant may vary to save power and eliminate drift issues. The
time constant may be, for example, t.sub.1/2=2 seconds, or t.sub.1/2=2
seconds.
[0287] FIG. 11B shows a kinetic profile of a bolus delivery of fluid by
the fluid delivery device 10. A rapid succession of about 29 pump
actuations (i.e., pulses) each displace fluid from a fluid source into
the resilient dispensing chamber 122, thus causing corresponding changes
in the parameter measured by the acoustic volume measurement sensor 550.
It can be seen that the volume of the dispensing chamber 122 expands on
the first pump pulse to about 1.5 .mu.l, a value similar to that observed
in FIG. 11A. The dispensing chamber 122 volume further expands upon
additional pulsatile pumping at pulse intervals shorter than the time
period required to achieve full discharge of the dispensing assembly 120;
the expansion reaches a maximum of about 6 .mu.l. Cessation of the pump
pulsing occurs after about 85 seconds and the volume of the chamber 122
is seen to decrease with an exponential decay kinetic resulting in
complete discharge of its contents by about 30 seconds after cessation of
pumping. The t.sub.1/2 for this final discharge is approximately the same
as for the basal delivery shown in FIG. 11A. The calculated cumulative
output volume is seen to rise during pumping with an approximately linear
kinetic and plateau upon cessation of pumping.
[0288] In the described system, fault conditions are detected by volume
measurements rather than by pressure measurements, thus, faults may be
determined in seconds. FIGS. 11C-11F illustrate the sensor 550 of FIGS.
5-7 detection various types of fault conditions. All description with
respect to FIGS. 11C-11F are described with reference to FIGS. 5-7.
[0289] FIG. 11C shows a kinetic profile of sensor 550 output over time for
a pumping pulse under normal operating conditions. In contrast, FIG. 11D
shows an expected result of an occlusion downstream of the dispensing
assembly 120; the increasing (or not decreasing) volume of fluid in the
dispensing chamber 122 is quickly detected by the sensor 550.
[0290] Low volume conditions are shown in FIGS. 11E-11F. In FIG. 11E, an
approximate maximum sensor signal is reached, followed by an overly fast
decay; this condition may indicate an internal leak in the pump 16, line
310, or dispensing assembly 120. The kinetic profile of FIG. 11F has a
low peak volume signal and may be representative of a pump failure, an
empty reservoir 20, or an occlusion that is upstream of the dispensing
chamber 122. Delayed expansion of the dispensing chamber 122 in response
to pump actuation may also indicate a problem in the flow line 310. The
sensor 550 may also be capable of detecting bubbles in the fluid. An
alarm can be activated in response to detection of a fault condition.
[0291] FIG. 12 shows a flow chart depicting a cycle of acoustic volume
sensing and compensation (corresponding to control loop 360 of FIGS.
2A-3). The sensor may measure the amount of fluid dispensed from the
device 10 based on measures of the magnitude of the cyclical changes in
the variable volume chamber 121 induced by the pumping cycles. For
example, the sensor 550 may repeatedly acquire acoustic spectra of the
resonant variable volume 121 and the reference volume chamber 127 (step
2611) and maintains a parameter, which, for each pumping pulse, is
updated to incorporate the decrease in volume of gas in the variable
volume chamber 121. Accordingly the updated parameter indicates the net
quantity of fluid that has entered the dispensing chamber 122. The fluid
entering the dispensing chamber 122 is approximately equal to the volume
that has been dispensed by the device 10 if there is sufficient delay
between pulses. Alternately, the sensor 550 can repeatedly measure the
increase in the volume of gas in the variable volume chamber 121 to
determine the amount dispensed by the device (if there is a sufficient
delay between pulses). Acoustic spectra are compared to model spectra in
a lookup table that may correspond to any or all of a dispensing chamber
122 with a bubble, without a bubble, or with bubbles of varying sizes
(step 2621). The lookup table may hold data acquired experimentally,
determined using a model, or determined to work empirically. The lookup
table may contain data representing varying bubble containing and/or
normal conditions for multiple degrees of expansion of dispensing chamber
122. If the spectrum and updated sum fit a model of normal flow (step
2631), another acoustic spectrum is acquired and the cycle is repeated at
step 2611. If the spectrum and/or the updated sum do not fit a model of
normal flow, the presence of a low or occluded flow will be determined
(step 2641). A low or occluded flow may be indicated by a persistently
out-of-range volume of the variable volume chamber 121, by an updated sum
that is lower than a predicted or set value, or both. If a low or
occluded flow condition is detected, an alarm will be triggered (step
2671). Alarms may include audible signals, vibrations, or both. If no
condition of low or occluded flow is found, the device determines if the
spectrum fits a model corresponding to a condition of a bubble in the
dispensing chamber 122 (step 2661). If a bubble is determined to be
present, a reaction is initiated that may include an alarm and/or
compensatory action which may include temporarily increasing the rate of
pumping (step 2651) and the cycle will begin again at step 2611. If it is
determined that no bubble is present, an alarm is triggered to indicate
an undetermined fault condition (step 2671). Embodiments of the present
invention may also utilize bubble detection using AVS technology as
disclosed in co-pending U.S. Patent Application Ser. No. 60/789,243,
which is incorporated herein by reference.
[0292] The pumping assembly 16 of FIGS. 2A-3 urges fluid from the
reservoir 20 to the dispensing assembly 120. When a dispensing assembly
according to FIGS. 6-7 is used, it is not necessary to use a high
precision pump, because the feedback provided from the dispensing
assembly 120 to the pumping assembly 16 allows adjustment of the pumping
assembly 16 based on exact measurements of the volume being delivered.
The individual pumping pulses may be of sufficiently low volume to allow
precise compensation based on the feedback. Many different pumping
assembly 16 implementations can therefore be employed. Various possible
embodiments of the pumping assembly 16 are described below.
[0293] FIGS. 13 and 14 schematically show alternate embodiments of some of
the components in a fluid delivery device according to an embodiment of
the invention. FIG. 13 shows a flow line 310 with a pumping assembly 16
having a pumping element 2100 located between an upstream one way valve
21 and a downstream one way valve 22. The pumping element 2100 may use an
actuator to deform a portion of the flow line to generate pressure in the
flow line 310. The upstream one way valve 21 inhibits retrograde flow
from the pumping element 2100 toward a fluid source (not shown), while
the downstream one way valve 22 inhibits retrograde flow from the
volume-sensing chamber 120 to the pumping element 2100. As a result,
fluid is driven in the direction of the exit assembly 17, which, in one
embodiment, includes a high-impedance passage.
[0294] In an alternate embodiment shown in FIG. 14, the functions of the
pumping element, i.e., generating pressure in the flow line 310, and the
upstream one way valve 21 are performed by a combined valving pump 2200.
Thus, the pumping assembly 16 in the FIG. 14 embodiment is made up of two
components--the combined valving pump 2200 and the downstream one way
valve 22--instead of the three components used in the FIG. 13 embodiment.
Other embodiments of the pumping assembly 16 may be used. The combination
of valving and pumping functions in valving pump 2200 may be accomplished
by a variety of mechanisms, some of which are described below with
reference to FIGS. 15A-16 and 22-56.
[0295] In many of the embodiments described below, the poppet for the
inlet valve 21, the poppet for the exit valve 22 and the pumping
actuation member 54 are all either directly or indirectly (e.g., as in
FIGS. 50-56) in communication with the fluid line 310 such that each of
these elements are able to create or react to various fluid pressures. As
noted above, the upstream and downstream valves--which may also be
referred to herein as the inlet and exit valves--are one way valves. The
valves can be volcano, flapper, check or duck-bill valves, amongst other
types of one way valves, or other types of valves that bias the flow
toward the device output. An example of volcano valves are disclosed in
U.S. Pat. No. 5,178,182 issued Jan. 12, 1993 to Dean L. Kamen, and
incorporated herein by reference.
[0296] In the embodiment shown in FIGS. 15A-15D, the pumping assembly
includes both an inlet valve 21 and an exit valve 22, each of which
includes a fluid inlet, a fluid exit, and a moveable member (which is,
for each valve, a portion of membrane 2356). The pumping assembly also
includes a pumping element 2100. The pumping element is located
downstream from the inlet valve 21 and upstream from the exit valve 22.
In the following description, the exit valve will be starting from the
closed position, i.e., fluid is not flowing through the exit valve.
However, at a time when the fluid presents enough pressure, the fluid
pressure opens the exit valve by placing pressure on the membrane and the
exit valve's poppet 9221 to open the valve, and the fluid can then flow
through the exit valve 22. The embodiment of FIGS. 15 A through 15D may
be considered to be a combined valving-pump (like item 2200 in FIG. 14),
in the sense that a single mechanical action both occludes a pump inlet
and then urges flow through a pump outlet.
[0297] This pumping arrangement has the advantage of partitioning the
moving parts and wetted line components to opposite sides of a flexible
barrier membrane 2356. As a result, the moving parts may be located in a
reusable component and the wetted parts (fluidic line 310) may be located
in a disposable component.
[0298] In a preferred embodiment of the pumping mechanism, the fluid
source is a non-pressurized reservoir. When the moveable member of the
inlet valve is in the open position, and a negative pressure exists in
the pumping chamber, a pressure differential exists that pulls the fluid
from the reservoir towards the inlet valve. This negative pressure may be
created by the resiliency of the membrane in the pumping chamber. In one
alternative embodiment, a spring--which may be built into the
membrane--may be used to assist in the recoil of the membrane in the
pumping chamber. The non-pressurized reservoir may be collapsible, so
that when fluid is drawn from it, a corresponding collapse in the
reservoir reduces its volume. As a result, build-up of negative pressure,
or air in the reservoir is prevented.
[0299] In a preferred embodiment of the pumping mechanism, after the inlet
valve is closed, pressure is applied to the pumping chamber forcing fluid
from the pumping chamber towards the exit valve. Pressure created by the
pumping motion opens the exit valve and allows fluid to flow through the
exit valve's fluid exit.
[0300] The moveable member can be anything capable of functioning as
described above. In some embodiments, the moveable member is a flexible
membrane or a resilient pumping diaphragm. In other embodiments, the
moveable member is a ball-shaped rigid structure or another object
capable of preventing fluid from flowing out of an opening in the fluid
path.
[0301] In practice, the pumping mechanism may be primed prior to use.
Thus, the pumping mechanism cycles through a number of strokes, purging
air from the fluid line, until most or all of the air in the fluid line
is purged. Many of the pumping mechanisms disclosed herein have the
ability to "self-prime" because the fluid volume contained outside the
pumping chamber, but between the valves, is small. When the pump squeezes
air in the pump chamber, it generally builds up enough pressure to blow
past the exit valve. The subsequent return stroke can therefore develop
sufficient negative pressure for the pump to pull liquid from the
reservoir. If the "dead" volume of the pump is too large, the air in the
pumping chamber may not build up enough pressure to escape the exit
valve. As a result, the pump may stall.
[0302] FIGS. 15A-15D, 16 and 22-56 show several embodiments of the pumping
mechanism. Referring now to FIGS. 15A-15D, one embodiment of the pumping
mechanism is shown exemplifying several steps in the pumping process: 1.
fluid passing through the inlet valve 21 (as shown in FIG. 15B); 2. the
inlet valve closed (as shown in FIG. 15C); and 3. the pumping actuation
member 54 forcing fluid downstream, with fluid pressure opening the exit
valve 22 and flowing through the fluid exit (as shown in FIG. 15D).
[0303] The pumping mechanism of FIGS. 15A-15D includes a moveable member,
which, in this embodiment, is a portion of the flexible membrane 2356.
The inlet and exit valves include poppets 9221, 9222 that function as
valve occluders. Each of the poppets 9221, 9222 and the pump actuation
member 54 include a spring 8002, 8004, 8006. The pump plate 8000 is
attached to both the pump actuation member 54 and the inlet poppet 9221
and serves as a terminus to their respective springs 8004, 8002.
[0304] The term "poppet" is used to denote a member that applies pressure
against the moveable member (i.e., the membrane) to affect the position
of the membrane. Although other designs may be used, some specific
examples of spring-loaded poppet valves that utilize structures and
principles of mechanical advantage are described below (in connection
with FIGS. 50-56). However, mechanisms other than poppets can be used to
perform the same function. In FIGS. 15B-15D, the inlet valve 21 includes
a fluid inlet and fluid exit, part of the membrane 2356, and a poppet
9221. The exit valve 22 includes a fluid inlet a fluid exit, part of the
membrane and a poppet 9222.
[0305] In the embodiment shown in FIGS. 15A-15D, the fluid path 310 is
defined by a structure (item 9310 in FIG. 15A), which may be rigid or
have some flexibility (preferably less flexibility than membrane 2356. As
shown in FIG. 15A, the housing structure 9310 defines the valving
chambers 9321, 9322 and the pumping chamber 2350; all three of these
chambers are in the fluid path 310.
[0306] Referring now to FIGS. 15B-15D, the inlet valve 21, exit valve 22
and pump element 2100 each have a fluid inlet and a fluid exit. The
pumping actuation member 54 has a pumping chamber 2350 where the fluid
flows after exiting the inlet valve. Pumping actuation member 54 applies
pressure onto the membrane 2356, creating positive pressure in the fluid
line.
[0307] As shown in FIGS. 15B-15D (and similarly for the valve seat 4070
for the outlet valve shown in FIGS. 50-56), the valve seat 9121 in the
inlet valve 21 is preferably spaced away from the membrane 2356, when the
membrane is not being actuated by the poppet 9221 of the inlet valve.
[0308] The fluid line 310 is partially defined by a membrane 2356. In this
embodiment, the membrane 2356 separates parts of the pumping mechanism
from the fluid. Thus, the fluid line 310 is wetted and the pumping
actuator 54 and the valve poppets 9221, 9222 are not wetted. However,
alternative embodiments of the pumping assembly do not need to include a
membrane 2356 that is in contact with the fluid line 310. Instead, a
different moveable member may be used for the valves and/or pump. In
still other embodiments, only parts of the fluid line 310 are separated
from the pumping mechanism, thus partially wetting the pumping assembly.
[0309] The inlet poppet 9221 includes an end 8018 referring to the surface
area of the inlet poppet that contacts the membrane portion of the fluid
line 310. The pumping actuation member 54 includes an end 8012 that
contacts the membrane portion of the fluid line 310. Likewise, the exit
poppet 22 includes an end 8022 that contacts the membrane portion of the
fluid line 310. The ends 8018, 8022 of the valve poppets apply pressure
onto their respective areas of the membrane 2356, blocking or unblocking
the respective portions of the flow path 310. The end 8012 of the
pressure actuation member also applies pressure onto its respective area
of the membrane, so as to cause flow through the fluid line 310.
[0310] The pumping actuation member 54 is surrounded by a plunger biasing
spring 8004. The plunger biasing spring 8004 has both a terminus at the
pump plate 8000 and at 8014, a support structure that also holds the
pumping actuation member.
[0311] The inlet poppet 21 is surrounded by an inlet poppet spring 8002,
although in alternate embodiments, the inlet poppet itself is resilient
and so serves the function of the spring. The inlet poppet spring 8002
has both a terminus at the pump plate 8000 and near the end 8018 of the
inlet poppet 9221.
[0312] The exit poppet 9222 is surrounded by a passive exit poppet spring
8006. The exit poppet spring 8006 has both a terminus at an exit poppet
plate 8024 and the lip 8020 near the end of the exit poppet 9222.
[0313] In each case, the springs 8002, 8004, 8006 terminate before the
respective ends and do not interfere with the surface areas 8018, 8012,
8022 that contact the membrane 2356.
[0314] In a preferred embodiment, the fluid pumping device also includes
at least one shape memory actuator 278 (e.g., a conductive shape-memory
alloy wire) that changes shape with temperature. The temperature of the
shape-memory actuator(s) may be changed with a heater, or more
conveniently, by application of an electric current. FIGS. 15B-15D show
an embodiment with one shape memory actuator 278, however, in other
embodiments (described below) there may be more than one shape memory
actuator 278. In one embodiment, the shape memory actuator is a shape
memory wire constructed of nickel/titanium alloy, such as NITINOL.TM. or
FLEXINOL.RTM.. However, in other embodiments, any device capable of
generating a force, such as a solenoid, could also be used. In certain
embodiments, the shape memory actuator 278 has a diameter of about 0.003
inches and is about 1.5 inches in length. However, in other embodiments,
the shape memory actuator 278 may be made from any alloy capable of
contraction with heat (and expansion may be aided by a mechanism that
imparts force on the alloy so as to stretch the alloy to the original
length, i.e., a spring, although such a mechanism is not required) so as
to actuate the pumping mechanism as described in the embodiments herein.
In certain embodiments, the diameter of the shape memory actuator 278 can
be from 0.001 inches to any diameter desired and the length can be any
length desired. Generally speaking, the larger the diameter, the higher
the available contraction force. However, the electrical current required
to heat the wire generally increases with diameter. Thus, the diameter,
length and composition of the shape memory alloy 278 may affect the
current necessary to actuate the pumping mechanism. Irrespective of the
length of the shape memory actuator 278, the actuation force is
approximately constant. Increase in actuation force can be imparted by
increasing the diameter of the shape memory actuator 278.
[0315] The shape memory actuator 278 connects to the pump plate 8000
through connector 8008. Connector 8008 is described in more detail below.
The shape memory actuator 278 connects to a fluid pumping device by way
of terminus connector 8010. Depending on the device or system in which
the pumping mechanism is used, the terminus connection location will
vary. The terminus connector 8010 is described in more detail below.
[0316] FIGS. 15B-15D show the pumping mechanism and fluid line 310 having
already been primed as discussed above. Referring now to FIG. 15B, the
inlet valve 21 is open, and the pumping actuation member 54 is not
pressing against the membrane 2356. The exit valve 22 is in the closed
position. The shape memory actuator 278 is in an expanded position. In
this configuration, fluid is pulled from a reservoir (not shown) to the
inlet valve 21 fluid inlet. (Although shown as a bulge in the membrane in
the inlet valve region, the pulling of fluid in this step may cause a
depression in the membrane, or no deformation of the membrane). When the
inlet poppet is in the open position, the fluid can flow from the fluid
inlet to the fluid exit and into the pumping chamber 2350. At this point,
the exit poppet end 8022 is firmly pressed against the membrane 2356 and
seals the exit valve 22.
[0317] Referring next to FIG. 15C, electrical current has been applied to
the shape memory actuator 278, and the shape memory actuator is
contracting from a starting length towards the desired end length. The
contracting of the shape memory actuator 278 pulls the pump plate 8000
towards the fluid line 310. The inlet poppet 9221 and the pumping
actuation member 54 are both connected to the pumping plate 8000. The
motion of the plate 8000 pulls both the inlet poppet 9221 and pumping
actuation member 54 towards the membrane 2356. As shown in FIG. 15C, the
inlet poppet end 8018 is pressed firmly against the membrane 2356,
sealing the membrane against the valve seat 9121 and, closing the inlet
valve 21. (The motion of the inlet poppet can force a small amount of
fluid in the inlet valving chamber, item 9321 in FIG. 15A, through either
the fluid inlet or the fluid exit of the inlet valve 21.)
[0318] Simultaneously, the pumping actuation member 54 begins its path
towards the pumping chamber 2350. During this process, as the inlet
poppet spring 8002 is compressed (at this point, the inlet poppet end
8018 is pressing firmly against the fluid line 310), the pump plate 8000
and pumping actuation member 54 continue traveling towards the fluid line
310. The inlet poppet spring 8002 allows the pump plate 8000 to continue
moving toward the fluid line 310 with the pump actuation member 54 even
when the inlet poppet 9221 can not travel any further.
[0319] Referring now to FIG. 15D, the pumping actuation member 54 presses
against the area of the membrane 2356 over the pumping chamber 2350 and
the fluid is pumped so as to increase the pressure of the fluid in the
pumping chamber 2350. The exit poppet end 8022 remains pressing firmly
(aided by the exit poppet spring 8006) on the membrane 2356 sealing the
fluid inlet and fluid exit of the exit valve 22 until the pressure from
the fluid flowing from the pumping chamber 2350 forces exit valve 22
open. Upon reaching a sufficient pressure, the fluid exits through the
fluid exit of the exit valve 22, thus overcoming the pressure exerted
against the membrane 2356 by the exit valve 22. Upon cessation of flow,
the exit valve 22 is forced closed by the passive spring 8006.
[0320] During the work stroke, the pump actuation member spring 8004 is
loaded. Eventually, the pump actuation member spring 8004 will pull the
pump actuation member 54 away from the membrane 2356. As a result, during
the relaxation stroke, the spring 8004 returns the pump actuation member
54, and pumping plate 8000 to the relaxed position of FIG. 15C; the
loaded inlet poppet spring 8002 may also contribute energy to the return
stroke. As the pumping plate 8000 nears its relaxed position, it engages
a cap of the inlet poppet 9221 to lift and unseat the inlet poppet so as
to open the inlet valve 21. The pump actuation member spring 8004 also
unloads during the return stroke.
[0321] The pump plate 8000, reaching a threshold distance where the inlet
poppet spring 8002 is at the same level as the pump plate 8000, will
unload with the pump actuation member spring 8004. The membrane 2356 in
the pumping chamber 2350, being resilient, will return to its starting
position. This creates a negative pressure and as the inlet valve opens,
fluid will flow through the inlet valve's fluid inlet to the fluid exit
and towards the pumping chamber 2350. Thus, the pumping mechanism will
now be in the state as shown in FIG. 15B.
[0322] The entire pump sequence described with respect to FIGS. 15B-15D
will repeat each time the pump is actuated through application of current
onto the shape memory actuator 278.
[0323] The membranes referred to herein, including membrane 2356, may be
made from any resilient material capable of imparting the necessary
characteristics to function as described herein. Additionally, the
membrane material may include a biocompatible material so as not to
impede operation of the pump or diminish the therapeutic value of the
fluid. Multiple biocompatible resilient materials may be suitable,
including nitrile and silicone. However, different therapeutic fluid
compositions may require different choices of resilient material.
[0324] The pumping mechanism described above and also various embodiments
as described herein can be described in terms of stroke length. One way
to determine stroke length is by the total change in the length of the
shape memory actuator during one cycle of contraction and expansion of
the shape memory actuator. This difference will determine the total
distance the pump rod travels and thus, the total amount of fluid that
flows out of the inlet chamber 2354 to the pumping chamber 2350, to the
exit chamber 2352 and finally, out the exit chamber 2352. Another way to
determine stroke length is the travel distance of the pump plate 8000.
For a partial stroke, the pump plate 8000 will not reach its maximum
travel distance. In one embodiment, very small or micro-strokes are
initiated continuously, pumping micro-liter volumes of fluid on a
continuous or regular basis, from the reservoir to the exit. For example,
a micro-stroke may displace less than 20%, 10% or 1% of the volume of the
pumping chamber 2350.
[0325] FIG. 16 shows a variation of the pumping mechanism embodiment shown
in FIG. 15B. In FIG. 16, two different shape memory actuators--a longer
one and a shorter one--are used. FIG. 16 shows an embodiment of the
pumping mechanism shown in FIG. 15B in which the shape memory wire 278 is
tensioned around a pulley 286 and splits into longer and shorter strands.
A common juncture serving as a negative terminal may be located where the
longer and shorter strands split off. Completion of a circuit with either
or both of the alternate paths allows adjustment of the pumping force
and/or stroke length. In an alternative embodiment, a piece of material,
such as Kevlar material, extends from the common junction around the
pulley to the force plate 8000, while two separate pieces of shape memory
wire extend from the common junction to their respective supports. These
embodiments provide both a pumping mode and an air purging mode, as
described below, by using two wires with different lengths.
[0326] With respect to varying stroke using the shape memory actuator
variables, for a given length of shape memory actuator, the stroke is
dependent on a number of variables: 1. total time electricity/heat is
applied; 2. total voltage of the electricity; and 3. the diameter of the
shape memory actuator. Some variable embodiments are shown in FIGS.
17-19. However, in some embodiments, the stroke can be varied while
maintaining the length, electricity time and voltage. These embodiments
include multiple shape memory actuators (see FIG. 19) and multiple
switches on a single shape memory wire (see FIG. 17). As discussed above,
the desired stroke length can also be attained by modifying any one or
more of the variables.
[0327] Additionally, the timing of the application of heat or electric
current to the shape memory actuation can vary to control the stroke.
Each time the shape memory actuator is heated can be termed a pulse.
Factors such as the pulse frequency, pulse duration, and stroke length
may affect the amount of fluid delivered over time.
[0328] FIGS. 17-19 additionally depict embodiments of pumping assemblies
which have both a fluid pumping mode and an air purging mode. When
activated, the air purging mode applies a compression stroke of increased
displacement and/or increased application of force by a force application
member. The air purging mode may be activated based on the likelihood or
knowledge of air being present in the pumping assembly. For example, the
air purging mode may be activated when the line is attached to a
reservoir, when a bubble is detected by a sensor or sensing apparatus, or
when insufficient flow is detected by a sensor or sensing apparatus.
Alternately, the two modes may be used to select between displacing a
smaller and a larger volume of fluid for a given pumping pulse.
[0329] Referring now to FIG. 17, a schematic shows a pumping assembly
actuated by a shape memory actuator 278 and having multiple modes of
operation. When a pumping chamber 2350 is filled with fluid, the pumping
assembly operates in a fluid pumping mode. During fluid pumping mode,
electrical current flows between a negative electrical lead 2960 and a
positive electrical lead 2961, causing resistive heating of the alloy
shape memory actuator 278 and a resultant phase change and power stroke.
In one embodiment, during priming of the pumping mechanism or when a
bubble 2950 is suspected to be in the pumping chamber 2350, the air
purging mode is activated and electrical current flows along a path of
extended length between a negative electrical lead 2960 and a positive
electrical lead 2965; the result is a compression stroke of greater force
on and displacement of force application member 2320 which should be
sufficient to displace air 2950 from the pumping chamber 2350 to the pump
outlet 2370. In alternate embodiments, the positive and negative leads
may be reversed.
[0330] Referring now to FIG. 18, a schematic shows an alternate pumping
assembly having a plurality of shape memory actuators 278 having the same
length. The additional actuators may be used to increase the actuating
pressure on the pumping chamber 2350, for example, to remove an occlusion
or air bubble in the fluid line, pumping chamber or other area of the
pumping mechanism. The additional actuators may also provide a redundancy
to any pumping device. A single shape memory actuator may be capable of
imparting sufficient force to remove an air-bubble from the pumping
chamber. Additionally, in the embodiment shown in FIG. 18, an additional
return spring may be necessary depending on the length of the second
shape memory actuator.
[0331] When a reservoir is first attached to a flow line having a pumping
assembly, the pumping mechanism (item 16 in FIGS. 13-14) is typically
filled with air. Air can also enter the pumping mechanism during normal
operation for various reasons. Since air is more compressible than fluid,
application of a compression stroke of a length that is sufficient to
displace a fluid may be insufficient to generate enough pressure to
overcome the cracking pressure of a one way valve of the pumping
mechanism if there is a substantial amount of air in the fluid line.
Accordingly, the pumping mechanism may stall. However, it may be desired
to force air through the line during priming or when an innocuously small
amount of air is present in the pumping assembly. Thus, the embodiments
shown in FIG. 18 can be used to impart additional force in this
situation.
[0332] FIG. 19 schematically shows an alternative pumping assembly 16
having a plurality of shape memory actuators. A first, shorter, shape
memory actuator 2975 has a first electrical lead 2976 and a second
electrical lead 2977. The shorter actuator 2975 is capable of generating
compression strokes that are sufficient to displace fluid in the pumping
chamber 2350; the shorter shape memory alloy actuator 2975 is used during
normal fluid pumping mode operations. When an air purging mode is
indicated, or a larger pumped fluid volume is required, a second longer
shape memory alloy actuator 2970 may be used by sending a current along
an actuator length disposed between a first electrical lead 2973 and a
second electrical lead 2972. The longer shape memory alloy actuator 2970
may also be used as a backup actuator for fluid pumping mode operation by
creating a shorter circuit which includes an electrical path between a
first electrical lead 2972 and a second electrical lead 2971. The shorter
shape memory actuator 2975 may also be used to vary the stroke volume to
provide better control at lower fluid volume rates. The multiple mode
actuators of FIGS. 17-19 are not limited to use with the pump components
shown and may be employed with any of the various embodiments of pumping
mechanisms described herein including those using fluid pumping devices
as described below and those employing valving pumps as described below.
Thus, the desired stroke length can be initiated by applying
electricity/heat to the length shape memory actuator that will provide
the desired stroke length.
[0333] Referring now to FIGS. 20A and 20B, each shows one embodiment for
attaching the shape memory actuator. These various embodiments can be
used in any of the mechanisms or devices described herein which employ a
shape memory actuator 278. Referring to both FIG. 20A and FIG. 20B, the
shape memory actuator 278 is fed into a grommet 280. The grommet 280 is
then attached to a part 284. Although only two embodiments of this mode
of attachment are shown, various other modes are used in other
embodiments. Other modes of attaching a grommet to a part or any fixed
location can be used.
[0334] Referring now to FIGS. 21A and 21B, two exemplary embodiments of
attaching the shape memory actuator 278 for use with a pumping mechanism
16 are shown. In each of these embodiments, the shape memory actuator 278
is designed to turn around a pulley 286. Referring to FIG. 21A, the shape
memory actuator 278 is attached to a piece 288, preferably made of KEVLAR
material, by way of grommet 280. One end of the shape memory actuator 278
is shown attached to a part 284 by way of a set screw attachment 289.
Referring now to FIG. 21B, one end of the shape memory actuator is shown
attached to a part 284 by a grommet 280.
[0335] Various embodiments of the pumping mechanism are shown in herein.
The pumping mechanisms may include an inlet valve, a pumping actuation
member and an exit valve. As discussed above, different types of one way
valves may be used in alternative embodiments. Although the schematic
shown in FIGS. 15A-15D shows one embodiment, the following figures show
alternate embodiments.
[0336] Referring now to FIG. 22 and FIG. 23, a side view and a cross
section of a section of a pumping mechanism is shown. In this embodiment,
the pumping actuation member is a pumping elongate finger 32. When force
is exerted onto the finger 32, the finger 32 depresses the moveable
member and reduces the internal volume of the fluid line. The section of
the pumping mechanism in FIGS. 22 and 23 shows only the pumping chamber.
When combined with one way valves (items 21 and 22 of FIG. 13),
application of a deforming force to moveable member 23 urges fluid to
flow toward an exit assembly (not shown). As shown in FIGS. 22 and 23,
the finger 32 is pointed for focusing of force, but in other embodiments,
the finger 32 may be flat, or of any other suitable shape. A spring 31
serves to bias the finger 32 toward a retracted position with respect to
the resilient member 23 so that the finger 32 returns to the retracted,
non depressing position in the absence of application of force. As shown
in FIG. 23, a motor can be used to apply force onto the finger 23.
However, in other embodiments, a shape memory actuator is used. Various
types of motors will be suitable including electric motors and
piezoelectric motors.
[0337] Referring to both FIGS. 22 and 23, a backstop 33 limits the
potential travel of the finger 32, supports the moveable member 23, and
ensures a reduction of volume in the fluid line or pumping chamber by
preventing the moveable member 23 from moving out of position in response
to application of force by the finger 32. As seen in FIG. 22, the
backstop 33 may advantageously have a shape complementary to the
resilient member 23. In various embodiments, the pumping assembly 16 may
include a lever or crank driven on one end by a motor, compressing the
resilient member 23 at another end.
[0338] Referring now to FIG. 24, another embodiment of the pumping
actuation member is shown in relation to one section of the pumping
assembly. A motor or shape memory actuator (not shown) applies a rotating
force to a grouping of coupled projections 42. These projects 42 serve as
the pumping actuation member and, in turn, apply force to the moveable
member 23 in turn. Accordingly, intermittent pulses of force are applied
to the moveable member 23. The backstop 33, as shown, can travel within a
housing 44 and is upwardly biased toward the resilient member 23 by a
spring 46.
[0339] Referring now to FIG. 25, an embodiment of a force application
assembly with a pumping actuation member (here, a plunger) 54 inside a
barrel 52 is shown. A motor causes the plunger 54 to be alternately
withdrawn and inserted into the barrel. When the plunger 54 is withdrawn,
a negative pressure draws fluid from the reservoir (not shown) into a
channel 51 and a lumen 56. When the plunger 54 is inserted, the increased
pressure in combination with the one way valves (not shown) drives fluid
towards the dispensing assembly (not shown). The lumen 56 is connected to
the channel 51 via a connecting channel 58 and the volume of the barrel
lumen 56 decreases with the plunging action of the plunger 54 thereby
urging fluid through the flow line 310.
[0340] FIGS. 26 and 27 show another embodiment where the pumping actuation
member is a plunger 54. A force application assembly and a linear
actuator, that includes a shape memory actuation 278, drive the plunger
54. In FIG. 26, a shape memory wire 278 is in a cool, expanded state and
is attached to a first support 241 and a plunger attachment cap 244. The
cap 244 is in turn attached to a biasing spring 243 which is in turn
attached to a second support 242. When the wire 278 is in an expanded
state, the biasing spring 243 is in a relaxed state. FIG. 27 shows the
shape memory actuator 278 in a contracted state due to application of an
electric current to the wire 278 and coincident heating. Upon
contraction, a force is exerted on the cap 244 causing an inserting
movement of a plunger 54 and a corresponding pumping action. In the
contracted state, the biasing spring 243 is in a high potential energy
state. Upon cessation of application of the electric field, the Nitinol
wire 278 cools and expands again, allowing the biasing spring 243 to
return the plunger 54 to its retracted state. As shown in FIG. 21A-21B, a
shape memory actuator 278 may be wound around one or more pulleys.
[0341] FIGS. 28-30 show a variety of embodiments in which pumping is
accomplished by a pumping actuation member 54 using a shape memory
actuator 278 to compress a moveable member forming a pumping chamber. The
pumping chamber is bounded by one way valves 21, 22. FIG. 28 shows an
embodiment including a pumping mechanism where the pumping actuation
member is a plunger 54 in a barrel 52. The mechanism also includes a
lever 273, a fulcrum 274, and a shape memory actuator 278. A shape memory
actuator 278 is held within a housing 298 and is attached at one end to a
conductive support 279 and at the other end to a positive terminal 275 of
a lever 273. The lever 273 is in turn attached at its center to a fulcrum
274 and at a second end to a plunger 54. An electric current is applied
to cause current to flow through the terminal 275, the shape memory
actuator 278, and the conductive support 279, thereby causing the shape
memory actuator 278 to contract, causing lever 273 to pivot about the
fulcrum 274 and effect withdrawal of the plunger 54. Cessation of the
current allows cooling of the shape memory actuator 278, allowing it to
expand. The return spring 276 acts via the lever 273 to return the
plunger 54 to an inserted position within the barrel 52. The return
spring 276 is held in a housing 277. An o-ring 281 prevents leaking of
fluid from the plunger 54-barrel 52 assembly. The insertion and
withdrawal of plunger 54 causes fluid to flow through the flow line in a
direction determined by the orientation of two check valves: a first one
way valve 21 and a second one way valve 22. Any suitable backflow
prevention device may be used, which include one way valve, check valves,
duck bill valves, flapper valves, and volcano valves.
[0342] FIG. 29 shows another embodiment of a pumping mechanism having a
plunger 54, a barrel 52, and a force application assembly that includes a
shape memory actuator 278. However, this embodiment, unlike the
embodiment shown in FIG. 28, does not include a lever. A shape memory
actuator 278 is held within a housing 298 and is attached at one end to a
conductive support 279 and at the other end to a plunger cap 244 by way
of contact 275. The plunger cap 244 is attached to the plunger 54. Once
ample electric current is applied through a contact 275, the shape memory
actuator 278 contracts. This contraction causes a pulling on the plunger
cap 244 to effect insertion of the plunger 54 into the barrel 52.
Cessation of the current allows cooling and of the shape memory actuator
278, thereby allowing it to expand. Upon expansion of the wire, the
return spring 276 acts to return the plunger 54 to a withdrawn position
within the barrel 52. The return spring 276 is held in a housing 277.
O-rings 281 prevent fluid from leaking plunger 54-barrel 52 assembly. The
insertion and withdrawal of the plunger 54 causes fluid to flow through
the flow line in a direction determined by the orientation of a first one
way valve 21 and a second one way valve 22.
[0343] Referring now to FIG. 30, an embodiment of a pumping device using a
plunger 54 and a barrel 52 is shown. In this embodiment, a shape memory
actuator 278 in the form of a wire positioned in a shaft within the
plunger 54 is used to impart force on the plunger. The shape memory
actuator 278 extends from a plunger cap 272 through a shaft in a plunger
54 and through a channel 58 to a supporting base 299. O-rings 281 and 282
seal the plunger 54, barrel 52, and channel 58. Application of electrical
current to a first lead 258 and a second lead 257 causes heating of the
shape memory actuator 278 which results in contraction of the shape
memory actuator 278. Contraction of the shape memory actuator 278 causes
a downward force sufficient to overcome the upward bias of a return
spring 276 to be exerted on the plunger cap 272, thereby driving the
plunger 54 into the lumen 290 of the barrel 52. Expansion of the shape
memory actuator 278 allows the return spring 276 to return the plunger 54
to a withdrawn position. The insertion and withdrawal of plunger 54
causes fluid to flow through the flow line in a direction determined by
the orientation of a first one way valve 21 and a second one way valve
22.
[0344] An alternate embodiment of the pumping mechanism is shown in FIG.
31. The pumping actuation member is an assembly 101 that combines the
functions of a reservoir and pumping mechanism. Under the command of a
controller 501, a motor 25 drives a plunger 102 to create pressure in a
reservoir 104, thereby forcing fluid through a first one way valve 106.
Fluid then enters the resilient dispensing chamber 122 of a volume
sensing assembly 120 with a sensor 550, and to an exit assembly 17. An
optional second one way valve 107 may be included. Feedback control
between the sensor 550 and the motor 25 via the controller 501 assures
the desired flow of fluid to the patient. The first one way valve 106
serves to prevent reverse flow of fluid due to the resilient force of the
dispensing chamber 122 of the volume sensing assembly 120 when the
chamber is filled and extended. The second one way valve 107 serves to
prevent reverse flow of fluid from the exit assembly 17 or patient 12
into the dispensing chamber 122. In this embodiment, the sensor 550 can
immediately detect the volume in the dispensing chamber 122.
[0345] FIGS. 32-34 schematically show sectional views of a combined
valving pump 2200. FIG. 32 shows the valving pump 2200 with a collection
chamber 2345 and a pumping chamber 2350 in a resting position, prior to
actuation; FIG. 33 shows the valving pump 2200 in an actuating state
during a compression stoke; and FIG. 34 shows the pump in an actuated
state at the end of a compression stroke. A pump inlet 2310 is in fluid
communication with an upstream fluid source, such as a reservoir, and
connects to a first end of a channel 2360. The channel 2360 connects at a
second end to the collection chamber 2345, which is in fluid
communication with a diaphragm aperture 2390 disposed in a resilient
pumping diaphragm 2340. The collection chamber 2345 is bounded on a first
side by the resilient pumping diaphragm 2340 and on a second side by a
resilient pumping membrane 2330. The pumping membrane 2330 may be made
from, among other things, latex or silicone rubber. The downstream side
of the diaphragm aperture 2390 opens into the pumping chamber 2350.
During priming of the pump and between actuation cycles, fluid travels
from a fluid source such as a reservoir, through the pump inlet 2310, the
channel 2360, the collection chamber 2345, and the diaphragm aperture
2390, and then arrives in the pumping chamber 2350. A one way valve 22
prevents fluid from leaving the pumping chamber 2350 via a pump outlet
2370 until and unless ample fluid pressure is exerted against the one way
valve 22 such that the one way valve 22 is open. In FIG. 32 a pumping
actuation member 2320 is shown in a resting position, and the resilient
pumping membrane 2330 is shown in a relaxed configuration of minimal
surface area, thereby maximizing the volume of the collection chamber
2345. Although in this embodiment, the pumping actuation member is shown
as a ball, in other embodiments, the pumping actuation member can be
anything capable of actuation and applying ample force against the
resilient pumping membrane 2330 in order to actuate the pumping
mechanism.
[0346] As can be seen from FIG. 33, when the pumping actuation member 2320
is actuated during a compression stroke, the pumping actuation member
2320 begins to travel toward the diaphragm aperture 2390 of the resilient
pumping diaphragm 2340 and distends the resilient pumping membrane 2330,
causing retrograde flow of fluid that has collected in the collection
chamber 2345. Later in the force application stroke, as shown in FIG. 34,
the pumping actuation member 2320 will sealingly lodge the resilient
pumping membrane 2330 against the diaphragm aperture 2390. To aid in
sealing, the pumping actuation member 2320 may have a shape that is
complementary to the shape of the diaphragm aperture 2390. For example,
the pumping actuation member 2320 may be spherical or conical and the
diaphragm aperture 2390 may be a cylindrical through-hole. At this stage
of the force application stroke, retrograde flow from the pumping chamber
2350 will be inhibited. Continued travel of the pumping actuation member
2320 will deform the resilient pumping diaphragm 2340 and increase the
pressure in the pumping chamber 2350, while continuing to seal the
diaphragm aperture 2390 against retrograde flow from the pumping chamber
2350. When the pressure within the pumping chamber 2350 provides ample
fluid pressure against the one way valve one way valve 22, fluid will
flow from the pumping chamber 2350 through the pump outlet 2370. During
the return stroke, the pumping actuation member 2320, resilient pumping
membrane 2330 and resilient pumping diaphragm 2340 return to the relaxed
positions shown in FIG. 32. During the return stroke, the internal
pressure of pumping chamber 2350 and collection chamber 2345 will drop,
which should encourage refilling of the valving pump 2200 by inducing
flow of fluid from the fluid source through the pump inlet 2310 and
channel 2360.
[0347] Referring now to FIG. 35, a schematic sectional view of one
embodiment of a resilient pumping diaphragm 2340 is shown. A diaphragm
body 2515 may be constructed of a resilient material such as silicone
rubber. A diaphragm spring 2510 may also be included to impart resiliency
to a flexible, or already resilient, body 2515. The diaphragm spring 2510
may be embedded within the resilient pumping diaphragm 2340 or disposed
adjacent to the resilient pumping diaphragm 2340. An example of one
embodiment of a diaphragm spring 2510 can be seen in FIG. 36. A
combination of a diaphragm body 2515 that includes a compliant material,
and a diaphragm spring 2510 that includes a resilient material may be
used; the result is a pumping diaphragm 2340 that will exhibit a high
degree of sealing when contacted with the resilient pumping membrane 2330
deformed by a pumping actuation member (not shown, see FIGS. 32-34) and
also have a high degree of resiliency. A valve seat 2517 may be
positioned around the diaphragm aperture 2390. The valve seat 2517 may
function as a receptacle for the deformed portion of the resilient
pumping membrane 2330 The force application member 2320 may deform the
pumping membrane 2330, causing the membrane 2330 to deform and sealingly
contact the valve seat 2517. If sufficient force is applied, the valve
seat may be resiliently deformed to ensure a thorough seal against
retrograde flow of fluid. The ratio of the section height to the section
width of the valve seat 2517 can generally be selected differently and
matched to the circumstances of the flow.
[0348] Now referring to FIG. 36, an example of a diaphragm spring 2510 for
use in the pumping diaphragm 2340 of FIG. 35 is shown. An outer annulus
2520 and an inner annulus 2540 are connected by at least three resilient
arms 2530. The center of the inner annulus 2540 has a spring aperture
2550, which may be aligned with the diaphragm aperture 2390 of the
pumping diaphragm 2340 as shown in FIG. 35.
[0349] Referring now to FIG. 37, a schematic is shown representing a
sectional view of the valving pump 2200 previously shown in FIGS. 32-34
in combination with a force application assembly which includes a pumping
actuation member 2320, an actuator, and a lever 273. When energized by an
actuator, such as a shape memory actuator 278, the lever 273 pivots
around a fulcrum 274 to initiate a compression stroke. A hammer 2630
protrudes from the lever 273. During the compression stroke, the hammer
2630 contacts a rounded pumping actuation member 2320, causing the
pumping actuation member to travel within a void in a support structure
2660, and pushing the pumping actuation member 2320 against a resilient
pumping membrane 2330 until the pumping actuation member 2320 is held
sealingly against a diaphragm aperture 2390 located in the resilient
pumping diaphragm 2340. As the lever 273 continues travel, the pumping
actuation member 2320 causes deformation of a pumping diaphragm 2340.
When enough fluid pressure is exerted onto the one way valve 22, the one
way valve 22 opens. This allows the fluid to flow from a pumping chamber
2350 through a pump outlet 2370. Upon cooling of the shape memory
actuator 278, the resiliency of the pumping diaphragm 2340 and the
resilient pumping membrane 2330 will cause return of the lever 273 to a
starting position determined by a lever stop 2650 and lever catch 2640.
Alternately, a return spring (not shown) may be used to return the lever
273 to the starting position. Although shown as a sphere, the force
application member 2320 may alternately be a piston, a protrusion of the
lever 273 or other suitable form.
[0350] FIG. 38 schematically shows a sectional view of an embodiment of a
valving pump using a resilient cylindrical flexure 2670. In one
embodiment, the resilient cylindrical flexure is made from rubber, but in
other embodiments, it can be made from any resilient material. The
cylindrical flexure 2670 has a central passageway 2675, and a plurality
of resilient radial fins 2672 that are sealingly arranged against a
housing 2673. Fluid entering through a pump inlet 2310 passes through a
channel 2360 and collects in regions upstream of a one way valve 22: a
collection chamber 2345, the central passageway 2675 of the cylindrical
flexure 2670, and a pumping chamber 2350. The pumping chamber is coupled
in fluid communication with the collection chamber 2345 through the
central passageway 2675. During the pumping mechanism's compression
stroke, a pumping actuation member 2320 applies force to, and deforms, a
resilient pumping membrane 2330 until the resilient pumping membrane 2330
is sealingly held against a valve seat 2680 of the cylindrical flexure
2670; retrograde flow to the pump inlet 2310 from the collection chamber
2345 is thereby blocked. Continued travel of the pumping actuation member
2320 causes deformation of the cylindrical flexure 2670; the pressure
within the pumping chamber 2350 increases until such time that it is
ample to open the one way valve 22. Fluid can then flows through a pump
outlet 2370.
[0351] The pumping actuation member 2320 is shown as a ball shape in FIG.
38. However in other embodiments, the pumping actuation member 2320 can
be any shape that can function as described above.
[0352] Referring now to FIG. 39, an alternate embodiment of the
cylindrical flexure 2670 (shown in FIG. 38) employing a resilient portion
2680 and a rigid cylindrical support 2690 is shown. Like the cylindrical
flexure 2680 of FIG. 38, the resilient portion of the cylindrical flexure
2670 includes a valve seat 2680 which seals the central passageway 2675
upon application of force by a pumping actuation member 2320. Thus, the
resilient portion 2680 of the cylindrical flexure 2670 deforms to
transmit pressure to the pumping chamber 2350.
[0353] FIGS. 40-44 schematically show sectional views of an alternate
embodiment of a valving pump in various states of actuation. The valving
pumps 2200 of FIGS. 40-44 have a resilient diaphragm spring 6100 and a
resilient sealing membrane 6120 which together serve a function that is
similar to that of the resilient pumping diaphragm 2340 of the valving
pump 2200 shown in FIGS. 32-34. FIG. 40 shows the valving pump 2200 in a
resting state. In the resting state, fluid may flow from the inlet 2360,
into an upper portion 2346 of the collection chamber 2345, through an
aperture 6110 in the diaphragm spring 6100 and into a lower portion 2347
of the collection chamber 2345. Fluid then may proceed through one or
more openings 6130 in a sealing membrane 6120 and into the pumping
chamber 2350. Under low-pressure conditions, further fluid flow is
hindered by a one way valve 22. The spring diaphragm 6100 and sealing
membrane 6120 may both be constructed from resilient, biocompatible
materials. The spring diaphragm 6100 may have a greater resiliency than
the sealing membrane 6120. For example, the spring diaphragm 6100 may be
a circular piece of flexible bio-inert plastic and the sealing membrane
6120 may be a sheet of silicone or fluorosilicone elastomer.
[0354] FIGS. 41 and 42 show the valving pump 2200 in two intermediate,
partially actuated states. The pumping actuation member 2320 deforms the
pumping membrane 2330 and forces it through the collection chamber 2345
and against the spring diaphragm 6100, which, in turn, is deformed and
forced against the sealing membrane 6120. At this point in the
compression stroke, retrograde flow through either the aperture 6110 of
the spring diaphragm 6100, or through openings 6130 in the sealing
membrane 6120, or both, are suppressed. Offset placement of the sealing
membrane openings 6130 relative to the spring aperture 6100 allows a seal
to be created between the spring diaphragm 6100 and the sealing membrane
6120. In some embodiments this seal may be supplemented with a redundant
seal between the fill chamber resilient pumping membrane 2330 and the
spring diaphragm 6100 (the embodiments of FIGS. 43-44, for example, lack
this redundant seal). A circumferential ridge (not shown) around the
spring diaphragm aperture 6110 may act as a valve seat to enhance the
seal.
[0355] Referring now to FIG. 42, continued travel of the pumping actuation
member 2320 causes further deformation of the pumping membrane 2330,
spring diaphragm 6100, and sealing membrane 6120. As a result, fluid in
the pumping chamber 2350 is compressed until the fluid pressure forces
the one way valve 22 open; further compression causes fluid egress
through the outlet 2370.
[0356] An alternate embodiment of the valving pump 2200 of FIGS. 40-42 is
shown schematically in FIG. 43. In this embodiment, a pumping actuation
member 2320 traverses the resilient pumping membrane 2330. The pumping
membrane 2330 is sealingly attached to the circumference of the pumping
actuation member 2320 at a midpoint along the length of the pumping
actuation member 2320. When actuated, the diaphragm spring aperture 6110
is sealed against backflow by the sealing membrane 6120 alone; the
resilient pumping membrane 2330 will not contact the aperture 6110. An
alternate embodiment of the device shown in FIG. 40 is shown in FIG. 44.
[0357] Referring now to FIG. 45, a sectional view of an alternate
embodiment of a combined valving pump 2200 is shown. A shape memory
actuator 278 actuates a compression stroke which causes a resilient pump
blade 2710 to lever about a fulcrum 274, causing the resilient pumping
membrane 2330 to be deformed. The resilient pump blade 2710 and resilient
pumping membrane 2330 apply pressure to fluid in a graded pumping chamber
2720 having a shallow region 2730 and a deeper region 2740. Early in the
compression stroke, the pump blade 2710 induces the resilient pumping
membrane 2330 to obstruct a channel 2360 that connects a pump inlet 2310
to the graded pumping chamber 2720. As the compression stroke continues,
force is applied to the fluid in the graded pumping chamber 2720 until
the fluid pressure in the graded pumping chamber 2720 is great enough to
open a one way valve 22. Fluid then exits a pump outlet 2370. The pump
blade 2710 may be constructed entirely or partly from a resilient
material such as rubber. In some embodiments, the resilient material
includes a non-resilient spline. Alternately, in some embodiments, the
resiliency is imparted through a resilient region 2750, thus, the
resilient region 2750 is the only resilient part of the pump blade 2710
in these embodiments. In these embodiments, the resilient region 2750
contacts the bottom of the graded pumping chamber 2720. The resiliency of
pump blade 2710 allows the compression stroke to continue after the
pumping blade 2710 contacts the base 2780 of the shallow region 2730. A
return spring (not shown) returns the pump blade 2710 to a starting
position during the return stroke.
[0358] Referring now to FIG. 46, a sectional view of an alternate
embodiment of a pumping mechanism is shown. This embodiment includes a
resilient pump blade 2710. The resilient pump blade 2710 includes a
resilient region 2830 which provides resiliency to the pump blade 2710.
The resilient region 2830 joins a pumping actuation member 2820 to a pump
blade 2810. When used with a valving pump (not shown) the resilient pump
blade 2710 of FIG. 42 will occlude the inlet channel (not shown, shown in
FIG. 45 as 2360) and then bend at the flexible region 2830 to allow the
force application member 2820 to apply further pressure to the fluid in
the graded pumping chamber (not shown, shown in FIG. 45 as 2720). The
force application member 2820 may be constructed entirely of a resilient
material such as rubber. However, in alternate embodiments, only a region
that contacts the bottom of the pumping chamber (not shown) is made from
resilient material. The resilient pump blade 2710 will return to its
relaxed conformation during the return stroke.
[0359] Referring now to FIG. 47, a sectional view of another embodiment of
pumping mechanism is shown. The pumping mechanism is shown where the
lever is at the intermediate stage of actuation with the inlet valve 2941
closed. The pumping mechanism includes a fluid line 2930, a moveable
member 2330, which is a membrane in this embodiment, an inlet valve 2941
poppet 2940, a pumping actuation member 2942, a pumping chamber 2350, and
an exit valve 22. The inlet valve 2941 and the pumping actuation member
2942 are each actuated by the shape memory actuator 278 which is
surrounded by return spring 276 and connected to a lever 273. The lever
273 actuates both the inlet valve 2941 and the pumping actuation member
2942. The lever 273 includes an elongate and spring member 2910 that is
attached to the lever 273 hinged to fulcrum 274 and terminated in a valve
actuation hammer 2946. The spring member 2910 may be curved. The spring
member 2910 biases the position of the valve actuation hammer 2946 away
from the lever 273 and toward the inlet valve 2941. The lever 273 has a
pump actuation hammer 2948, which is not attached to the spring member
2910, and is positioned adjacent to the pumping actuation member 2942.
[0360] Electric current causes the shape memory actuator 278 to contract
and the lever 273 pivots about the fulcrum 274. The pivoting places the
valve actuated hammer 2946 in position to force the inlet valve 2941
closed. As the shape memory actuator 278 continues to contract, the lever
273 continues pivoting and the pump actuation hammer 2948 forces the pump
actuation member 2942 against the pumping chamber 2350, even while
further compressing the elongate spring member 2910. Upon achieving
sufficient pressure, the fluid pressure opens the exit valve 22, and
fluid exits through the valve.
[0361] During the relaxation stroke, the return spring 276 unloads and
returns the lever 273 to the starting position, releasing the pumping
actuation member 2942. The inlet valve 2941 opens. The resiliency of the
pumping chamber 2350 causes the pumping chamber 2350 to refill.
[0362] Referring now to FIGS. 48 and 49 schematically show a cross section
of an embodiment in which a pumping mechanism employs a bell crank 7200
and combines a valving pump 2200 with a flow biasing valve. The bell
crack 7200 converts force produced by the linear shape memory actuator
278 into a transverse pumping force. FIG. 48 shows the mechanism in a
resting or refilling mode and FIG. 49 shows the mechanism in an actuated
state. Contraction of the actuator 278 causes the bell crank 7200 to
rotate around a shaft 7210 and press upon the force application member
2320, which drives a resilient membrane 7220 to seal against the
resilient pumping diaphragm 2340 and urge fluid from the pumping chamber
2350 toward the dispensing chamber 122. The return spring 276 cooperates
with a return spring support 7221 to release the pumping force, causing
the pumping chamber 2350 to expand and draw fluid from the reservoir 20.
Still referring to FIGS. 48 and 49, the flow biasing valve 4000 is also
shown, having a valve spring 4010, a poppet or plunger 4020.
[0363] In some of the embodiments of the pumping mechanism described
above, one or more aspects of the following valving operation description
is relevant. Referring now to FIG. 50, an example of a flow biasing valve
4000 is shown, closed. A valve spring 4010 exerts force on a poppet 4020
to sealingly press a valve membrane 4060 against a valve seat 4070
surrounding a terminal aperture of a valve outlet 4040. The valve seat
4070 may include a circumferentially raised portion to improve sealing.
As explained below with references to FIGS. 54-55, back pressure created
by the action of a resilient dispensing assembly should be insufficient
to cause retrograde flow through the flow biasing valve 4000. As shown in
FIG. 51, when the pumping assembly is actuated, sufficient pressure
should be generated to unseat the membrane 4060 and the poppet 4020 from
the valve seat 4070 thereby allowing fluid to flow from the valve inlet
4030, through an inlet chamber 4050 and to the valve outlet 4040. FIGS.
52-53 shows an alternate valve that has a valve seat 4070 without a
circumferentially raised portion.
[0364] Referring now to FIGS. 54 and 55, illustrations of how an exemplary
flow biasing valve discriminates between forward and retrograde flow are
shown. FIG. 54 schematically represents the valve in a closed position.
Back pressure in the outlet 4040 applies force to a relatively small area
of the flexible valve membrane 4060 adjacent to the valve seat 4070 and
is thus unable to dislodge the poppet 4020. Referring now to FIG. 55,
this FIG. schematically represents the valve during the actuation of a
pumping actuation member. The pressure of the pumped fluid applies force
over an area of the membrane 4060 that is larger than the area adjacent
to the valve seat. As a result, inlet pressure has a larger mechanical
advantage for unseating the poppet 4020 and forward flow should ensue in
response to the action of the pumping actuation member. Thus, the
critical pressure needed to displace the poppet 4020 is lower in the
inlet than in the outlet. Accordingly, the spring biasing force and the
size of the force application areas associated with both the fluid inlets
and fluid exits may be chosen so that flow is substantially in the
forward direction.
[0365] Referring now to FIG. 56, a sectional view of an adjustable flow
biasing valve 4130 which operates on a principal similar to the flow
biasing valve in FIG. 50, but allows adjustment of the pressure necessary
to open the valve, i.e., "cracking pressure" (which, in some embodiments,
can be from 0.2 to 20 pounds per square inch or "psi") is shown. The
cracking pressure is adjusted by turning a spring tensioning screw 4090,
which alters the volume of the recess 4080 to compress or decompress the
valve spring 4010 thereby altering the spring 4010 biasing force. The
valve spring 4010 biases a plunger 4100 against the valve membrane 4060
to force it against the valve seat. The plunger 4100 serves a force
application function similar to the fixed force poppet of the flow
biasing valve (shown as 4020 and 4000 respectively, in FIGS. 50-53).
Compressing the valve spring 4010 will increase its bias, thereby
increasing the cracking pressure. Conversely, decompressing the spring
4010 will decrease its bias and the associated cracking pressure. The
valve spring 4010 is positioned coaxially around the shaft of a plunger
4100 and exerts its biasing force on the plunger 4100. In some
embodiments, the shaft of the plunger 4100 may be shorter than both the
length of the valve spring 4010 and the recess 4080 to allow it to be
freely displaced in response to increased fluid pressure in the fluid
inlet 4030. The plunger 4100 may be any size necessary to function as
desired. As in the embodiment of FIGS. 50-53, the wetted parts may reside
in a disposable portion 2610 and the force application components (e.g.,
the plunger and spring) may reside in the reusable portion 2620. The
principal of operation is also similar; a larger mechanical advantage in
the fluid inlet 4030 relative the outlet 4040 favors forward flow versus
retrograde flow. Alternately, the plunger 4100 may be replaced by the
poppet (shown as 4020 in FIGS. 50-55). In some embodiments, it may be
desirable to eliminate the raised valve seat; in these embodiments, the
plunger may be ball shaped or another shape capable of concentrating the
force.
[0366] The flow biasing valve 4000 substantially reduces or prevents
retrograde flow from the dispensing chamber 122 into the pumping chamber
2350. As in FIGS. 50-56, a valve spring 4010 biases a poppet or plunger
4040 to press the membrane 7220 against a valve seat 4070 in a way that
provides mechanical advantage to forward flow through the line 310. By
serving the function of the pumping membrane 2330 and the valve membrane,
membrane 7220 allows the line 310, pumping chamber 2350 and pumping
diaphragm 2340 to reside in one component (e.g., the disposable portion
2610) and the remainder of the pumping mechanism in a second, removable
component (e.g., the reusable portion 2620). By placing the more durable
and expensive components in the reusable portion 2620, economy and
convenience may be realized.
[0367] The pumping mechanism described in the various embodiments above
can be used in various devices to pump fluid. As an exemplary embodiment,
the pumping mechanism described in FIGS. 59A-59E, FIGS. 60A-60D and FIGS.
60A-60C will be described as integrated into a fluid pumping device.
[0368] Referring FIGS. 57 and 58, alternate ways are shown for the fluid
schematic. These are two schematics where the reservoir 20 and pumping
assembly 16 are coupled to the dispensing assembly 120. In the embodiment
shown in FIG. 57, the reservoir and pumping assembly are coupled in
series to the dispensing assembly 120. In the embodiment shown in FIG.
58, a shunt line 150 is coupled from the output of the pumping assembly
16 back to the reservoir 20. Since much of the fluid output of the
pumping assembly 16 is returned to the reservoir 20 via the shunt line
150, the pumping assembly 16 can accommodate varieties of pumping
mechanisms 16 that may not function as desired in the embodiment shown in
FIG. 57. Thus, in some embodiments, where a large volume pumping
mechanism is employed, the shunt line 150 can impart small volume
functionality to a large volume pumping mechanism. One way valves 21 and
22 are oriented in the same direction and included to prevent unwanted
backflow.
[0369] Referring now to FIG. 59A, a fluid schematic of one embodiment of a
fluid pumping device is shown. In this embodiment, fluid is located in a
reservoir 20 connected to a fluid line 310. Fluid line 310 is in
communication with pumping mechanism 16, separated by a membrane 2356.
The fluid is pumped through a flow restrictor 340 to an infusion device
or cannula 5010 for delivery to a patient. It should be understood that
the infusion device or cannula 5010 is not part of the device as such,
but is attached to a patient for delivery of the fluid. System
embodiments are described in more detail below and these include an
infusion device or cannula 5010.
[0370] Referring now to FIG. 59B, an alternate embodiment of the schematic
shown in FIG. 59A is shown. In the embodiment shown in FIG. 59A, the
fluid is pumped through a flow restrictor 340 then through a cannula
5010. However, in FIG. 59B, the fluid is not pumped through a flow
restrictor; rather, the fluid is pumped, having the same impedance,
through the cannula 5010.
[0371] In both FIGS. 59A and 59B, the volume of fluid pumped to the
patient, in one embodiment, is calculated roughly by pump strokes. The
length of the stroke will provide for a rough estimate of the volume
pumped to the patient.
[0372] Referring now to FIG. 59C, a fluid schematic of one embodiment of a
fluid pumping device is shown. In this embodiment, fluid is located in a
reservoir 20 connected to a fluid line 310 by a septum 6270. Fluid line
310 is in communication with pumping mechanism 16, separated by a
membrane 2356. The fluid is pumped to a variable volume delivery chamber
122 and then through a flow restrictor 340 to a cannula 5010 for delivery
to a patient.
[0373] The volume of fluid delivered is determined using the dispensing
assembly 120 which includes an acoustic volume sensing (AVS) assembly, as
described above, a variable volume delivery chamber 122, and a dispensing
spring 130. Similarly to the pumping mechanism, a membrane 2356 forms the
variable volume dispensing chamber 122. The membrane is made of the same
material (or, in some embodiments, different material) from the membrane
2356 in the pumping mechanism 16 (described in detail above). The AVS
assembly is described in greater detail above.
[0374] Referring now to FIG. 59D, an alternate embodiment to the
embodiment shown in FIG. 59C, in this embodiment, there is no flow
restrictor between the variable volume delivery chamber 122 and the
cannula 5010. Referring now to FIG. 59E, an alternate embodiment to the
embodiment shown in FIG. 59C is shown, with an alternate pumping
mechanism 16.
[0375] Referring now to FIGS. 59A-59E, the reservoir 20 can be any source
of a fluid, including but not limited to a syringe, a collapsible
reservoir bag, a glass bottle, a glass vile or any other container
capable of safely holding the fluid being delivered. The septum 6270 is
the connection point between the fluid line 310 and the reservoir 20.
Various embodiments of the septum 6270 and the reservoir 20 are described
in more detail below.
[0376] The fluid delivery device embodiment shown in FIGS. 59A-59E can be
used for the delivery of any type of fluid. Additionally, the embodiments
can be used as one, two or three separate mating parts. Referring now to
FIGS. 60A-60D, the same embodiments described with respect to FIGS.
59A-59D are shown as separated into mating parts. Part X includes the
movable parts while part Y includes the fluid line 310 and the membrane
2356. In some embodiments of this design, part Y is a disposable portion
while part X is a non-disposable portion. Part X does not come into
contact directly with the fluid, part Y is the only part having wetted
areas. In the above embodiments, the reservoir 20 can any size and is
either integrated into the disposable or a separate disposable part. In
either embodiment, the reservoir 20 can be refillable. In embodiments
where the reservoir 20 is integrated into the disposable part Y, the
reservoir 20 can either be manufactured filled with fluid, or, a patient
or user fills the reservoir 20 using a syringe through the septum 6270.
In embodiments where the reservoir 20 is a separate mating part, the
reservoir 20 can either be manufactured filled with fluid, or, a patient
or user fills the reservoir 20 using a syringe (not shown) through the
septum 6270 as part of a reservoir loading device (not shown, described
in more detail below) or manually using a syringe through the septum
6270. Further detail regarding the process of filling a reservoir 20 is
described below.
[0377] Although various embodiments have been described with respect to
FIGS. 59A-59E and FIGS. 60A-60D, the pumping mechanism can be any pumping
mechanism described as embodiments herein or alternate embodiments having
similar function and characteristics. For example, referring now to FIG.
61A, a similar embodiment as that shown in FIG. 59A is shown having a
representative block that includes pumping mechanism 16. This is to show
that any pumping mechanism 16 described herein or functioning similarly
can be used in the fluid pumping device. Likewise, FIG. 61B and FIG. 61C
are representations of systems encompassing the embodiments FIG. 59B and
FIG. 59C respectively.
[0378] The schematics of a fluid pumping device described above can be
implemented in a device usable by a patient. There are a number of
embodiments. The device can be a stand-alone device or be integrated into
another device. The device can be any size or shape. The device can be
either portable or non-portable. The term "portable" means a patient can,
transport the device either in a pocket area, strapped to the body, or
otherwise. The term "non-portable" means that the device is in a
healthcare institution or in the home, but the patient does not carry the
device almost everywhere they move. The remainder of this description
will focus on portable devices as the exemplary embodiment.
[0379] With respect to portable devices, the device can be worn by a
patient or carried by a patient. In the embodiments where the device is
worn by a patient, this is referred to as a "patch pump" for purposes of
this description. Where the device is carried by a patient, this is
referred to as a "portable pump" for purposes of this description.
[0380] The following description is applicable to various embodiments for
either the patch pump embodiments or the portable pump embodiments. In
various embodiments, the device includes a housing, a pumping mechanism,
a fluid line, a moveable member, a reservoir, a power source and a
microprocessor. In various embodiments, a dispensing assembly, for
example a volume sensing device, which in some embodiments includes an
AVS assembly, are included in the device. Also, an embodiment can also
include a fluid restrictor, although it is not depicted in the following
figures, as the fluid line is shown as homogeneous to simplify the
illustration. For purposes of this description, where a dispensing
assembly is included, the exemplary embodiment will include an AVS
assembly. Although an AVS assembly is a preferred embodiment, in other
embodiments, other types of volume sensing device can be used. In some
embodiments, however, no volume sensing device is used, but rather,
either the reservoir itself will determine the volume of fluid delivered,
the pump stroke is used to roughly determine the amount of volume
delivered. It should be understood that the schematic devices shown
herein are meant to illustrate some of the variations in the device. The
embodiments represented by these schematics can each also include a
sensor housing, a vibration motor, an antenna, a radio, or other
components that are described with respect to FIGS. 70-70D. Thus, these
depictions are not meant to limit the components but rather to illustrate
how various components could interrelate in a device.
[0381] Referring now to FIG. 62A, schematics of a stand alone device 10
are shown. The housing 10 can be any shape or size and accommodates the
intended use. For example, where the device is used as a patch, the
device will be compact enough to be worn as such. Where the device is
used as a portable pump, the device will be compact enough to be used
accordingly. In some embodiments, the housing is made from plastic, and
in some embodiments, the plastic is any injection molded fluid-compatible
plastic, for example, polycarbonate. In other embodiments, the housing is
made from a combination of aluminum or titanium and plastic or any other
material, in some embodiments the materials are light and durable.
Additional materials may include, but are not limited to, rubber, steel,
titanium, and alloys of the same. As shown in FIG. 62A, the device 10 can
be any size or shape desired.
[0382] FIGS. 62A-69B are schematics showing representative embodiments.
The exact design is dependant on many factors, including, but not limited
to, size of the device, power restrictions and intended use. Thus, FIGS.
62A-69B are intended to describe the various features of a device and the
possible combinations, however, actual devices can be readily designed
and implemented by one or ordinary skill in the art. As examples,
embodiments of devices are described and shown below. However, these are
not intended to be limiting, but rather, are intended to be examples.
[0383] Referring now to FIG. 62B, with respect to the patch device, in
some embodiments, the housing 10 includes an insertion area viewing
window 342. This allows for the area on a patient where the infusion
device or cannula (not shown) is inserted to be viewed. Shown here is the
cannula housing 5030 area of the device 10. The viewing window 342 is
made from any material capable of being transparent, including, but not
limited to, plastic. Although the viewing window 342 is shown to be in
one particular location on one particular shaped device, a viewing window
342 can be integrated in any location desired in any housing embodiment.
[0384] Referring now to FIG. 63A, a device 10 is shown. A reservoir 20 is
shown connected to a fluid line 310, which is then connected to a pumping
mechanism 16. A dispensing assembly 120 is shown connected to the fluid
line 310. The pumping mechanism 16 and dispensing assembly 120 are
separated from the fluid line 310 by a membrane 2356. The cannula housing
5030 is downstream from the volume measuring device. Shape memory
actuators 278 are shown connected to the pumping mechanism 16. A
microprocessor on a printed circuit board 13 as well as a power source or
battery 15 are included. A flow impedance as described above can also be
implemented between the dispensing assembly 120 and the cannula housing
5030.
[0385] Referring now to FIG. 63B, a similar device 10 as shown in FIG. 63A
is shown, except in this embodiment, a dispensing assembly is not
included. In this embodiment, the volume of fluid delivered will depend
on either the pump strokes (number and length), the reservoir 20 (volume
and time), both, or any other method described previously with respect to
monitoring the volume of fluid delivered.
[0386] Referring now to FIG. 63C, a similar device 10 as shown in FIG. 63B
is shown, except the device 10 includes a dispensing chamber 122 and
sensor housing 5022.
[0387] Referring now to FIG. 64A, one embodiment of the patch pump device
10 is shown. This embodiment is based on the embodiment of the device 10
shown in FIG. 63A. In this embodiment, the patch pump device 10 is
divided into two sections: a top X and a base Y. The top X contains the
pumping mechanism 16, a dispensing assembly 120 (which is optional, but
is shown as an exemplary embodiment), the power supply 15, and the
microprocessor and printed circuit board 13. These are the non-wetted
elements, i.e., they do not come into direct contact with the fluid. The
base Y contains the fluid line 310 and the membrane 2356. Where the
reservoir 20 is built into the device, the reservoir is also contained on
the base Y. However, in embodiments where the reservoir 20 is a separate
mating part, the reservoir 20 is connected to the fluid line when fully
assembled (see FIG. 66A-66D and description referring thereto), however,
is not built into the device.
[0388] The patch pump device also includes a cannula housing 5030. This is
the area the cannula line 5031 is located. Part of the fluid line 310,
the cannula line 5031 allows a cannula (or other infusion device) to
receive the fluid and deliver the fluid to a patient (not shown).
[0389] Referring now to FIG. 65A, in some embodiments, the cannula 5010 is
inserted through the housing 5030 directly into the patient. The cannula
5010 is connected to a septum (not shown) connecting the cannula line
5031 to the cannula 5010. Referring now to FIG. 65B, in other
embodiments, an insertion set, (including the cannula and tubing, not
shown in FIG. 65B, but shown in FIG. 64B as items 5033 and 5010) is used;
thus, the tubing 5033 of the insertion set will connect to the cannula
line 5030 on one end and will connect to the cannula (not shown) on the
opposite end of the tubing.
[0390] Referring again to FIG. 64A, in use, the reservoir 20, having fluid
contained inside (which, as described above, is either molded into the
base Y or is separate and attached to the base Y) is connected to the
fluid line 310. The microprocessor on the printed circuit board 13 sends
a signal to activate the pumping mechanism 16 and a stroke is initiated
through electrical current being applied to the shape memory actuators
278. The fluid flows from the reservoir 20, in the fluid line 310 to the
dispensing assembly 120, or AVS assembly. There, the exact volume of
fluid inside the AVS chamber is determined and the fluid is forced out of
the AVS chamber, to the cannula line 5031 and the cannula housing 5030.
[0391] Referring now to FIG. 64B, the device shown in FIG. 64A is shown
connected to an insertion set, tubing 5033 and cannula 5010. In FIG. 64C,
the base Y of the device is shown using an adhesive patch or pad 3100 to
the body of a patient 12. It should be noted that in this embodiment, the
element 3100 can be either a pad or patch. However, as described in more
detail below, item 3100 is called a patch, and item 3220 is called a pad.
For simplicity purposes only, item 3100 is used; however, in some
embodiments, a pad is used, thus item 3220 would be appropriate in those
circumstances.
[0392] The cannula 5010, which is inserted through the cannula housing
5030 so that it mates by way of the cannula septum 5060 to the cannula
line 5031, is inserted into a patient 12. However, as shown and described
above with respect to FIG. 2B, the base Y can be fluidly attached to a
patient through an insertion set, which includes a tubing 5033 and a
cannula 5010. In both FIGS. 64B and 64C, the base Y can be adhered to a
patient either before or after insertion of the cannula 5010. Referring
again to FIG. 2C, the cannula 5010, once inserted into to the patient 12,
will receive fluid from the device directly without an infusion set
tubing (shown in FIG. 64B). The base Y is adhered to the patient 12 with
an adhesive patch 3100 either before or after insertion of the cannula
5010. Referring now to FIG. 64D, the top X of the device 10 is then
attached to the base Y of the device 10 after the cannula 5010 has been
inserted into the patient 12.
[0393] As described below, the adhesive patch can have many embodiments
and in some cases, the patch is placed on top of the device. Thus, the
patch shown in these embodiments is only one embodiment. As described
above, a pad, if used, would be placed in the same location as the patch
in FIGS. 64A-64D.
[0394] Referring now to FIGS. 66A-66D, in this embodiment, the reservoir
20 is shown as a separate part. As shown in FIG. 66A, the base Y includes
a reservoir cavity 2645 with a septum needle 6272. Shown in FIG. 66B, the
reservoir 20 is first placed in a top reservoir cavity 2640. At this
point, the reservoir 20 is not attached to the device. Now, referring to
FIG. 66C, when the top X is placed over the base Y, the reservoir 20 is
sandwiched into the base reservoir cavity 2645. Shown in FIG. 66D, the
force created by the attachment of the top to the base Y push the septum
needle 6272 into the septum 6270 of the reservoir 20 connecting the
reservoir 20 to the fluid line 310 of the base Y.
[0395] Referring now to FIGS. 67A-F, alternate embodiments of the
embodiments shown in FIGS. 64A, 64C and 66A-66D are shown. In these
alternate embodiments, in addition to a cannula housing 5030, the base Y
includes a sensor housing 5022. Referring now to FIGS. 69A-69B, both the
sensor housing 5022 and the cannula housing 5030 include an exit to the
underside of the base Y, shown in FIG. 69A as 5022 and 5030 respectively.
FIG. 69B depicts the embodiment shown in FIG. 69A with the sharps
protruding through the housings. The sensor housing accommodates a
sensor. In some embodiments, the sensor is an analyte sensor. Analytes
sensed include blood glucose, but in other embodiments, this analyte
sensor can be any type of analyte sensor desired.
[0396] Referring now to FIG. 67B, the base Y is shown on the body of a
patient 12. The sensor 5020 is shown having been inserted through the
base Y sensor housing 5022 and into the patient 12. Referring now to FIG.
67C, in some embodiments, the cannula 5010 and sensor 5020 are inserted
though their respective housing (5030 and 5022) and into the patient 12
simultaneously. Referring next to FIG. 67D, the base Y is shown attached
to the patient with both a cannula 5010 and sensor 5020 attached to the
patient 12 through the base Y.
[0397] Referring now to FIG. 67E, the base Y is shown attached to a
patient 12 and the cannula 5010 inserted through the cannula housing
5030. In this embodiment, the sensor housing 5022 is shown without a
sensor. However, a sensor 5020 is shown inserted into the patient 12 in
another location. Thus, the sensor 5020 is not required to be inserted
through the base Y, but embodiments described below relating to
monitoring blood glucose and pumping insulin through a cannula can be
implemented in this way. Additionally, other embodiments relating to
administering a fluid in response or relation to an analyte level can be
administered this way.
[0398] Referring now to FIG. 67F, the device 10, having both a sensor 5020
and a cannula 5010 through the base Y is shown with the top X placed on.
Again, in the embodiments shown in FIGS. 66A-66D, once the top X is
placed onto the base Y, the reservoir 20 is fluidly connected to the
fluid line 310.
[0399] Referring now to FIG. 68, one embodiment of the portable pump
embodiment of the device 10 is shown. In this device 10, an insertion
set, including a cannula 5010 and tubing 5033, is necessary to connect
the fluid line in the device 10 to the patient 12. Thus, the cannula 5010
is not connected, in this embodiment, through the portable pump device 10
to the patient 12 directly. Additionally, although this embodiment can
function as described below with respect to an analyte sensor and a fluid
pump, the sensor 5020 will be located outside the portable pump device 10
similar to the embodiment of the sensor 5020 shown in FIG. 5F.
[0400] Referring now to FIGS. 70-70D, both the patch pump and portable
pump embodiments as described additionally contain various components of
the dispensing assembly (in applicable embodiments) and for embodiments
including the AVS assembly, the various components thereof, including, at
least one microphone, a temperature sensor, at least one speaker, a
variable volume dispensing chamber, a variable volume chamber, a port and
a reference chamber. In some embodiments, the device contains one or more
of the following: a vibrator motor (and, in those embodiments, a motor
driver), an antenna, a radio, a skin temperature sensor, a bolus button,
and in some embodiments, one or more additional buttons. In some
embodiments, the antenna is a quarter-wavelength trace antenna. In other
embodiments the antenna may be a half-wavelength or quarter wavelength
trace, dipole, monopole, or loop antenna. The radio, in some embodiments,
is a 2.4 GHz radio, but in other embodiments, the radio is a 400 MHz
radio. In still other embodiments, the radio can be any frequency radio.
Thus, in some embodiments, the device includes a radio strong enough to
communicate to a receiver within a few feet in distance from the device.
In some embodiments, the device includes a second radio. In some
embodiments, the second radio may be a specific long-range radio, for
example, a 433 or 900 MHz radio or, in some embodiments, any frequency
within the ISM band or other bands, Not shown in FIGS. 70-70D, the
device, in some embodiments, contains a screen and/or a user interface.
[0401] The following description of these components and the various
embodiments thereof are applicable to both device types, and further, to
the various embodiments described with respect to each device type.
Referring now to FIG. 67F, for illustration purposes only, both the
cannula 5010 and the sensor 5020 have been inserted into the device 10.
Also, referring to FIGS. 70-70D, the various components, some of which
will not necessarily be included in all embodiments, are shown in a
schematic representing the electrical connections of those components.
FIGS. 70-70D therefore represent the various elements that could be
included in the device. These can be mixed and matched depending on size
requirements, power restrictions, usage and preferences, as well as other
variables. FIG. 70 shows the relation of FIGS. 70A-70D.
[0402] The device contains at least one microprocessor 271. This can be
any speed microprocessor capable of processing, at a minimum, the various
electrical connections necessary for the device to function. In some
embodiments, the device contains more than one microprocessor, as seen in
FIGS. 70A-70B, the device is shown having two microprocessors 271.
[0403] The microprocessor 271 (or in some embodiments, microprocessors) is
connected to the main printed circuit board (hereinafter, the "PCB"
refers to the term "printed circuit board") 13. A power source, which in
some embodiments is a battery 15, is connected to the main PCB 13. In one
embodiment, the battery 15 is a lithium polymer battery capable of being
recharged. In other embodiments, the battery can be a replaceable battery
or a rechargeable battery of any type.
[0404] In some embodiments, the device includes a radio 370 connected to
the main PCB 13. The radio 370 communicates to a remote controller 3470
using the antenna 3580. The communication between the device 10 and the
remote controller 3470 is therefore wireless.
[0405] In some embodiments, the device contains a vibration motor 3210.
The vibration motor 3210 is connected to a motor driver 3211 on the main
PCB 13 motor driver 3211.
[0406] Some embodiments include a bolus button 3213. The bolus button 3213
functions by a user applying force to a button form 3213, which can be
made from rubber or any other suitable material. The force actuates the
bolus button actuation, which is attached to a bolus button switch 3214
on the main PCB 13. The switch 3214 activates a single bolus which will
indicate a particular pre-determined volume of fluid is to be delivered
to the patient. After the user presses the bolus button 3213, in some
embodiments, the device 10 will generate an alarm (e.g., activate the
vibration motor 3210 and/or send a signal to the remote controller) to
signal to the user that the button 3213 was pressed. The user will then
need to confirm the bolus should be delivered, for example, by depressing
the button 3213. In still other embodiments, the remote controller 3470
queries the user to confirm the bolus should be delivered.
[0407] A similar query/response sequence may be used in various
embodiments to test and report on patient responsiveness. For example,
the device may be configured to test patient responsiveness by generating
an alarm (e.g., an audible and/or tactile alarm) and awaiting a response
from the patient (e.g., actuation of the button 3213). Such a test may be
performed at various times (e.g., every five minutes) or upon detection
of a condition such as an abnormal analyte level monitored via an analyte
sensor or an abnormal body temperature monitored via a temperature
sensor. If the patient does not provide an appropriate response within a
predetermined amount of time, the reusable portion may send an alarm to a
remote controller or caretaker. Such testing and reporting might be
particularly valuable for patients who could become unconscious or
incapacitated, either from a device malfunction or otherwise.
[0408] The NITINOL circuit (referring to the shape memory actuator, which
in some embodiments, is a NITINOL strand) 278 on the main PCB 13 provides
electrical current to the NITINOL connectors. As shown in FIG. 67F and
FIG. 70A, the device can include two NITINOL connectors 278 (and two
NITINOL strands). However, as described above, in some embodiments, the
device includes one NITINOL connector (and one NITINOL strand).
[0409] In some embodiments, the device includes a temperature sensor 3216
shown on FIG. 70B The temperature sensor 3216 is located on the underside
of the base Y and senses the temperature of the patient's skin. The skin
temperature sensor 3216 is connected to a signal conditioner, represented
by 3217. As shown in FIG. 70B, the signal conditioning 3217 is
represented as one block, however the device includes multiple signal
conditioners, as needed, each filtering different the signals. Following,
the AVS temperature sensor 132, AVS microphones 133, and analyte sensor
5020 are all connected to a signal conditioner, represented in one block
as 3217.
[0410] The AVS speaker 134 is connected to the speaker drive 135 on the
main PCB 13. The AVS speaker 134, in one embodiment, is a hearing aid
speaker. However, in other embodiments, the speaker 134 (a speaker
containing a voice coil, a magnet with an electromagnetic coil) is a
piezo speaker (shown in FIG. 50, representing one embodiment of the
device).
[0411] Referring still to FIGS. 70-70D, in some embodiments, the antenna
3580 has a dedicated PCB 3581, which is then connected to the main PCB
13. Also, in some embodiments, the AVS microphones 133 each have a
dedicated PCB 1332, 1333, connected to the main PCB 13. The various PCBs
may be connected to the main PCB 13 using conventional methods, for
example, flexible circuits or wires.
[0412] Referring to FIG. 67F, the device 10 is shown as an exemplary
embodiment for description purposes. However, the layout of the various
parts can vary and many of the embodiments are shown below. However,
additional alternate embodiments are not shown but can be determined
based on size, power and use.
[0413] In accordance with an alternate embodiment, the disposable portion
2610 may include the reservoir 20 and optionally, a battery. The
reservoir 20 may be integral to the disposable portion or otherwise
coupled to the disposable portion. The battery may be the primary or sole
power source for the device or may be a backup power source, and may be
used to provide electrical power to electronics on the reusable portion
and/or the disposable portion. Both the reservoir 20 and the battery will
typically require regular replacement, so including both of these
components in the disposable portion 2610 may provide to the user the
increased convenience of simultaneous replacement. Additionally, by
replacing the battery every time the reservoir is changed, the user may
be less likely to allow the battery to run down.
[0414] The disposable portion 2610 could additionally or alternatively
include a processor that may be used, for example, to continue certain
device operations in the event of a failure (e.g., a failure of a main
controller in the reusable portion), to generate an alarm in the event of
a failure, or to provide status information to the reusable portion. With
regard to status information, the processor could keep track of the
operation history and various characteristics of the disposable and hold
status information for access by the user, the fluid delivery device 10,
and/or the user interface 14 including during installation of the
disposable portion 2610. For instance, the processor can store status
related to shelf life, maximum exposure or operation temperature,
manufacturer, safe dispensing limits for the therapeutic, etc. If any of
these status indicators is determined by the device to be unacceptable,
the device can refuse to power the pumping assembly and dispensing
assembly and indicate to the user that the disposable is not usable. The
processor may be powered by a battery in the reusable portion or the
disposable portion.
[0415] More generally, the device may be configured to obtain status
information from any of the disposables (including, for example, the
disposable portion 2610 and any disposable component used therewith, such
as the fluid reservoir, battery, or sharps cartridge or individual sharps
component), for example, from a processor disposed in disposable portion,
via bar code reader, or via RFID technology. If the device detects a
problem with the disposables (e.g., invalid model number for use with the
reusable portion or an expiration date of the fluid has passed), then the
device may take remedial action, such as, for example, preventing or
terminating operation of the device and generating an appropriate alarm.
[0416] Additional components may be included in some embodiments. For
example, redundant failure detection and announcement mechanisms can be
employed. The device may employ an audible alarm. The loudspeaker 1202 of
the sensor 550 may be used for the audible alarm or an additional speaker
may be included loudspeaker and used for the audible alarm. The device
vibrating mechanism 3210 can also be used as an alarm. If a system
failure is detected that requires immediate attention, both alarms can be
activated. Additionally, a secondary battery or supercapacitor may be
employed as a backup to the primary battery. If either battery fails, the
controller can activate one or more alarms so that at least one
announcement of battery failure occurs.
[0417] The alarms can also be used to indicate to a user that the device
is working properly. For example, a user might program the device for a
bolus delivery over a certain period of time. The user may desire to know
that the programmed delivery is occurring properly. The processor can use
the vibrating motor or an audio sound to indicate successful programmed
delivery. Thus, some mechanisms can be employed in some embodiments of
the device to provide feedback, whether positive or negative, to the
patient or user.
[0418] A microphone may also be used to detect any abnormal vibration or
lack of normal vibrations and trigger an alarm condition. In various
embodiments, a microphone of the acoustic volume sensing system may be
used to perform such monitoring, or a separate microphone may be included
for such monitoring. Periodic checks can also be performed to determine
that the device is operating by checking for expected pump vibrations
with the microphone. If improper vibrations are detected, or if proper
vibrations are not detected by the microphone, an alarm can be activated.
[0419] Referring now to FIG. 71, various components of a device 10 are
shown schematically. In one embodiment of the device 10, a top X portion
mates with a base portion Y and a reservoir 20 is sandwiched between the
top X and base Y. The force of the sandwiching allows the reservoir
septum 6272 to mate with the base portion Y. In some embodiments, both an
infusion device 5010 and an analyte sensor 5020 are inserted through the
base Y and into a patient (not shown).
[0420] In many embodiments, the base Y and the reservoir 20 are disposable
portions and the top X is a non-disposable portion. Both the infusion
device 5010 and the analyte sensor are also disposable.
[0421] As previously discussed, the patch pump device may be entirely or
partially disposable. FIG. 72 shows an embodiment of a fluid delivery
device 10 having disposable and non-disposable portions. In this
embodiment, the disposable portion Y contains components that come into
direct contact with the fluid, including the collapsible reservoir 20,
pumping assembly (not shown), the variable volume dispensing chamber 122
(part of the dispensing assembly 120, located on the top X) and the flow
restrictor (not shown), as well as one way valves (not shown) and a fluid
path (not shown) connecting the reservoir to the pumping mechanism to the
variable volume dispensing chamber 122. Additionally, the disposable
portion Y includes a reservoir cavity 2645
[0422] The reusable portion X includes elements of the dispensing assembly
120 except the variable volume dispensing chamber 122, which is located
on the disposable portion Y. In some embodiments, the dispensing assembly
120 is an AVS assembly. The AVS assembly is described in detail above.
Referring now to FIG. 73, an integrated acoustic volume measurement
sensor is shown on a PCB.
[0423] Referring now to FIG. 74, the device 10 shown in FIG. 49 is shown.
The base disposable portion Y includes a reservoir cavity 2645. The top
non-disposable portion X includes battery 15 and a dispensing assembly
120. A microphone 133 is shown as well as a diaphragm spring 130. In some
embodiments, the dispensing assembly 120 includes more than one
microphone. Although throughout this description, each microphone is
referred to as 133, this does not infer that the microphones are always
identical. In some embodiments, the microphones are the same, in other
embodiments, the microphones are different.
[0424] In the FIG. 74, the top non-disposable portion X also includes main
PCB 13, a vibration motor 3210 and a pumping actuation member 54. The
top, non-disposable portion X includes the AVS assembly or dispensing
assembly 120. In FIG. 74, a microphone 133 is shown. The top,
non-disposable portion X also includes a battery 15, which may be used to
provide electrical power to electronics on the non-disposable portion
and/or the disposable portion. In some embodiments, this battery 15 is
rechargeable. Recharging can be done by methods described below. The
disposable portion Y includes the wetted components including a fluid
line (not shown) and the pumping assembly. In FIG. 74, only the pumping
plunger 54 can be seen. This embodiment of the device 10 can also include
many of the elements described above, including, but not limited to, a
fluid impedance, a flexible membrane, a cannula housing and a sensor
housing. Any pumping mechanism can be used.
[0425] Referring now to FIG. 75, the device 10 is shown in another view
where more elements are visible. In FIG. 75, the device 10 is shown with
base disposable portion Y including a coiled microtubing flow restrictor
340 and a fluid line 310 connecting the inlet 21 and outlet 22 valves.
The pumping actuation member 54 is also shown. The top X includes a main
PCB 13, a vibration motor 3210, two microphones 133, a speaker 134, a
reference chamber 127 and a fixed volume chamber 129. A battery 15 is
also shown. Since choosing a very small diameter for the flow restrictor
340, may cause occlusion of the line 310 (for example, due to protein
aggregates in a therapeutic fluid), it may be desirable to use a longer
length of tubing with a larger diameter. However, in order to pack a
longer length of tubing within a patch-sized housing, it may be necessary
to bend the tubing in to form a tortuous path, e.g, a coiled or
serpentine shape.
[0426] Referring now to FIG. 76, an exploded view of the device 10 shown
in FIGS. 72, 74 and 75 is shown. The top, non-disposable portion X is
shown separated from the base disposable portion Y. In practice, a
reservoir (not shown) would be placed in between the top X and base Y
portions. Once the top X and base Y are assembled to form a device 10,
the reservoir will become connected to the fluid line 310.
[0427] Referring now to FIG. 77, an exploded view of another embodiment of
a device 10 including a disposable base Y and non-disposable top X part
is shown. Also included is a reservoir 20, an adhesive 3100 and a bridge
5040 apparatus holding an infusion device 5010 and a sensor 5020. This
device 10 includes a more rounded footprint and a dome shape. A battery
15 and a main PCB 13 are shown located on the top X. The base Y includes
a reservoir cavity 2645. An adhesive 3100 is shown in a two piece
embodiment. The bridge 5040 is used to insert the infusion device 5010
and sensor 5020 through the base Y. The reservoir 20 is shown as having
an irregular shape, however, in other embodiments, the reservoir 20 can
have any shape and can vary in size according to the fluid capacity
desired. In this embodiment of the device 10, the non wetted components
are in the top non-disposable X and the wetted components are in the base
disposable Y.
[0428] When assembled, the device 10 may be adhered together using a
center region of the adhesive (not shown). Alternately, the device 10 may
be locked together mechanically using any of many embodiments described
herein for latching. Although some embodiments are described below
herein, many others will be apparent and as the shape of the device
varies, in many cases, the latch will also.
[0429] Referring now to FIG. 78, an exploded view of another embodiment of
the device 10 is shown. The top non-disposable portion X is mostly dome
shaped, however, a protrusion X1 is shown to accommodate the mechanisms
inside the top X. Thus, the shape of the device can vary and can include
polyps and protrusions, dimples and other texture-like features to
accommodate various designs of the device.
[0430] The reservoir 20, infusion device 5010 and sensor 5020 are shown.
The infusion device 5010 and sensor 5020 can be inserted through the base
Y and into a patient (not shown). The base Y is shown with an adhesive
3100 or pad 3220 underneath. In practice, the adhesive 3100 or pad 3220
can be first adhered to the skin and base Y. Next, the infusion device
5010 and sensor 5020 are inserted through the base Y into a patient (not
shown, shown in FIG. 79 as 5020 and 5010). The reservoir 20 is then
placed into the reservoir cavity 2645 either by first placing the
reservoir 20 into the top X then sandwiching the top X and the base Y,
or, placing the reservoir 20 into the reservoir cavity 2645 and then
sandwiching the top X and the base Y. Either way can be used. The final
result is the reservoir 20 becomes connected to the fluid line (not
shown) located in the base Y through a septum (shown upside down) on the
reservoir 20 and a septum needle (not shown, see 6272). The top X is then
fastened to the base X either through use of an adhesive, or in this
embodiment, mechanically using a latch 654 to clamp the top X and base Y
together.
[0431] The base Y includes those components that are wetted. The base Y is
disposable. The top X includes non wetted components. The top X is
non-disposable. Referring now to FIG. 79, the base Y includes a variable
volume dispensing chamber 122, an inlet valve 21, and exit valve 22 and a
pumping chamber 2350. As shown in this figure, those elements are shown
as the membrane covering the area that acts as either the chambers or the
valves. Thus, the base Y includes the membrane that securely maintains
the wetted areas, thus, maintaining the non wetted areas as such in the
top (not shown). As shown in FIG. 79, the sensor 5020 and the infusion
device 5010 have been inserted into their respective housings and through
the base Y to the patient (not shown). The base Y is shown with the
reservoir cavity 2645, but the reservoir (not shown) need to be connected
so that the fluid lines from the reservoir to the chamber and to the
infusion device are connected.
[0432] Referring now to FIG. 80, the top X of the device is shown. The top
X includes those non wetted components including, as shown, a temperature
sensor 3216, a diaphragm spring 130, an inlet valve poppet 21, and exit
valve poppet 22 and a pumping actuation member 54. The top Y also
includes a relief 2640 to accommodate the reservoir (not shown).
[0433] Referring now to FIGS. 81A-81C, a sequence is shown to illustrate
the process of sandwiching the reservoir 20 between the top X and base Y.
As seen in FIG. 81A, the top X as well as the reservoir 20 outside of the
top X are shown. The reservoir includes a septum 6270. The top X includes
a reservoir relief 2640. Next, as shown in FIG. 81B, the top is prepared
to sandwich with the base Y. Referring now to FIG. 81C, the reservoir 20
is placed, septum side down, inside the base Y. The septum will connect
with a cannulated septum needle (not shown) inside the base Y and connect
the reservoir to the fluid line (not shown). In alternate embodiments,
the reservoir may include a cannulated needle rather than a septum and
the fluid path may include a reservoir interface with a septum rather
than a cannulated needle.
[0434] Referring next to FIG. 82, the top X is shown with one embodiment
of the pumping mechanism 16 exploded. The pumping mechanism 16 fits into
the pumping mechanism housing 18 in the top X. The base Y is also shown
as well as one part of the latch 654 that will clamp the top X and base Y
together.
[0435] Referring now to FIG. 83, the base Y is shown with the fluid path
assembly 166 as the membrane 2356 exploded from the base Y. This
illustrates that in some embodiments of the device, the fluid path
assembly 166 is a separate part that is inserted into the base Y and
sandwiched with the membrane 2356. Also shown in this figure, the
adhesive or pad 3100/3220 in some embodiments, includes apertures for the
infusion device and sensor (not shown). Referring now to FIG. 84, a
bottom view of the base Y is shown. The bottom of the fluid path assembly
166.
[0436] Referring now to FIGS. 85A and 85B, another embodiment of the
device is shown. In this embodiment, the top X, also non-disposable,
includes a bolus button 654. The reservoir 20 is shown in an exploded
view, however, in one embodiment, the reservoir 20 is built into the base
Y. In another embodiment, the reservoir 20 is removable and placed into
the reservoir cavity 2645 using a process similar to that described above
with respect to another embodiment of the device.
[0437] The base Y is disposable and includes the wetted parts of the
device 10. The sensor 5020, the cannula 5010, the variable volume
dispensing chamber 122, the inlet valve area 21, the exit valve area 22
and the pumping chamber 2350. The volume dispensing chamber, the inlet
valve area 21, the exit valve area 22 and the pumping chamber 2354 are
all covered by membrane material, which may be in the form of a single
membrane or distinct membranes.
[0438] The device 10 is clamped together by a latch mechanism 654 on the
top X and the base Y. Referring now to FIGS. 85C-85D, the device 10 is
the latching mechanism 654 is shown in an open position (FIG. 85C) and a
clamped or closed position (FIG. 85D). The bolus button 3213, as
described in further detail above, can also be seen.
[0439] A cover (not shown) may be provided for use in any of the
embodiments of the device, to replace the reservoir and top portion when
the reservoir is removed while the base is connected to the patient. The
cover would not contain electrical components, thus, could be used in wet
conditions. However, in some instances, the reservoir can be removed
without the use of any cover.
Cannula and Inserter
[0440] FIG. 86A schematically shows a representative embodiment of the
infusion and sensor assembly 5040 including both an infusion device,
which can be a cannula or a needle 5010 and an analyte sensor, which
includes a sensor probe 5025 and a sensor base 5023. A bridge 5070
rigidly joins an infusion cannula 5010 and the analyte sensor base 5023.
The infusion device 5010 is bounded on an upper side by a septum 5060
which allows for fluid to flow from a source and be administered through
an infusion device 5010 to a patient. The sensor base 5023 is the section
of the analyte sensor that is not inserted into the patient. In one
embodiment, the base 5023 contains electronic contacts for the
electrochemical analysis of blood glucose. A probe 5025 protrudes from
the base 5023 of the analyte sensor 5020.
[0441] Referring now to FIG. 86B, in this embodiment, the infusion device
5010 is a cannula that is introduced into the patient using an
introducing needle 5240. The introduction needle 5240 is inside the
cannula 5010 when being inserted into a patient. After insertion of the
cannula 5010 into the patient, the introduction needle 5240 is removed
and the septum 5060 is sealed to a fluid source, which, in some
embodiments of the device described herein, is the fluid line. In some
embodiments, the sensor probe 5025 is associated with an introduction
needle 5072 which aids in skin puncture for insertion of the sensor probe
5025. The sensor introduction needle 5072, in some embodiments, at least
partially surrounds the sensor probe 5025 while the sensor probe 5025 is
being inserted into a patient.
[0442] In other embodiments, the infusion device 5010 is a needle and does
not require an introduction needle 5240. In these embodiments, the
infusion device 5010 is inserted into the patient and the septum 5060
seals with a fluid source.
[0443] In both FIGS. 86A and 86B, upon both the infusion device 5010 and
sensor probe 5025 being lined up appropriately, force is applied to the
bridge 5070. This forces both the infusion device 5010 and sensor probe
5025 into the patient. Once in the patient, releases 5052 are actuated
through holes, separating the infusion device 5010 and septum 5060, as
well as the sensor base 5023, from the bridge 5070. Referring to FIG.
86B, where introduction needles 5240 and 5072 are used, they will
typically remain attached to the bridge 5070 following insertion.
[0444] The bridge can be made from any material desired, including
plastic. The cannula can be any cannula in the art. The septum 5060 can
be made from rubber or plastic and have any design capable of imparting
the functions desired. In the embodiments where the infusion device is a
needle, any needle may be used. In embodiments where introduction needles
are used, any needle, needle device or introduction device can be used.
[0445] The infusion and sensor assembly requires force be applied in order
to be inserted into a patient. As well, the infusion and sensor assembly
requires that the infusion device and sensor are released from the
infusion and sensor assembly. Thus, both the force and the release can be
actuated manually, i.e., a person performs these functions, or an
insertion device may be used to actuate the assembly properly. Referring
now to FIGS. 87A-87E, an example of an inserter 5011 that can be manually
operated is shown. The infusion device 5010 and sensor 5023 are held by
the bridge 5070. The inserter 5011 includes covers 5012 for both the
infusion device 5010 and the sensor 5023. As shown in FIGS. 87B-87E,
using the inserter 5011, both the infusion device 5010 and the sensor
5023 are inserted through a device 10. Although FIG. 87A shows the sharps
exposed, in some embodiments, the covers 5012 completely encase the
sharps prior to the insertion process.
[0446] The inserter 5011 could be operated manually, but could also be
incorporated into another inserter device such that a mechanical
advantage can be applied. Referring now to FIGS. 88A-88B, one embodiment
of an inserter device 5013 is used with an apparatus similar to the
inserter 5012 shown in FIGS. 87A-87E. The mechanism of the inserter
device 5013 is shown in FIGS. 88C-88D. An actuation lever 5014 either
releases a spring (as shown in FIGS. 88C-88D) or provides another
mechanical advantage that allows for the inserter 5012 to be inserted
through a device (not shown). The inserter 5012 will thus release the
infusion device 5010 and sensor 5023 and then, the inserter 5012 can
either be removed from the inserter device 5013 and the inserter device
5013 refilled, or, the inserter device 5013 and inserter 5012 can be
discarded.
[0447] Various insertion devices are described herein. However, in other
embodiments, different insertion devices are used or the infusion device
and sensor are introduced manually.
[0448] Features may be included for securing the infusion and sensor
assembly 5040 to an automatic inserter. For example, the releases shown
in FIGS. 86A-86B as 5052 may receive pins of an automatic insertion
device. Referring to both FIGS. 89A and 89B a representative embodiment
of an automatic inserter 5100 is shown. As shown in the front view of
FIG. 89A, the inserter 5100 includes pins 5130 which travel in pin slots
5140 within an inserting cartridge recess 5120. In practice, the infusion
and sensor assembly (not shown, shown in FIGS. 86A and 86B as 5040) is
pressed into the cartridge recess 5120, causing pins 5130 to be inserted
into the holes in the infusion and sensor assembly (shown as 5052 in
FIGS. 86A and 86B). As shown in the rear view of FIG. 89B, a cocking
lever 5145 is used to ready the inserter 5100 for firing. The inserter
5100 is then either held against the skin or aligned with a cannula
housing and sensor housing on a base (not shown) and fired by pressing a
trigger 5110. Upon firing, the pins 5130 travel in their slots 5140,
thereby forcing the infusion device and sensor (both not shown) into a
patient. Inserter foot 5160 limits the downward travel of the infusion
and sensor assembly. The inserter may also automatically withdraw the
introduction needles (not shown, see FIG. 86B) from the infusion and
sensor assembly.
[0449] The infusion and sensor assembly may be preloaded in the inserter
5100 prior to distribution to an end user. As shown in FIG. 90, in other
embodiments, a cartridge 5080 may be used to protect a user and to
protect the sharps held in the assembly shown as 5040 in FIGS. 56A and
56B. Referring to both FIG. 90 and FIGS. 86A-86B and FIG. 89A, in the
cartridge embodiment 5080, the infusion and sensor assembly 5040 is
embedded in the cartridge 5080. The cartridge 5080 is mounted in the
cartridge recess 5120. The pins 5130 may project through the holes 5052
and into grooves 5090 in the cartridge 5080. Upon actuation of the
inserter 5100, the pins travel within the grooves 5090 as the 5080
travels toward the patient to insert the sharps. The cartridge 5080 may
be constructed of a rigid material.
[0450] Referring now to FIGS. 91A-91C, several views of an embodiment of
an inserter mechanism for an inserter, such as the one shown in FIGS. 89A
and 89B as 5100, are shown. FIG. 91A shows a perspective view, FIG. 91B
shows a front view, and FIG. 91C shows a side view of one embodiment of
an inserter mechanism. The inserter 5100 has a cocking lever 5145, which
connects via cocking linkages 5350 to a hammer cocking slide 5330, and is
used to move the cocking slide 5330 to a charged position. A power spring
5390 connects the hammer cocking slide 5330 to a trigger 5110 and, when
compressed, provides the downward force necessary for insertion of an
infusion device or an infusion and sensor assembly (not shown). A trigger
hammer 5340 is disposed under the hammer cocking slide 5330 and between a
pair of cocking linkages 5350; the trigger hammer 5340 transmits the
kinetic energy that is released from the power spring 5390 upon pressing
the trigger 5110. The energized trigger hammer 5340 impacts a cartridge
bolt 5380, positioned below. The cartridge bolt 5380 is linked to a
cartridge housing 5370, which holds the cartridge, for example, the one
shown in FIG. 90. The cartridge bolt 5380 is also disposed atop a return
spring 5360 for returning the cartridge housing 5350 to a retracted
position.
[0451] FIGS. 92A-92F schematically show a time sequence for the cocking
and firing of an inserter 5100 of the type described with reference to
FIGS. 91A-91C. FIG. 92A shows the inserter 5100 in a resting position.
Lowering the cocking lever (not shown, see FIG. 91A 5145) causes the
hammer cocking slide 5330 to lower and engage the trigger hammer 5340.
FIG. 92B shows the hammer cocking slide 5330 in a lowered position in
which it is engaged with the trigger hammer 5340. Raising the cocking
lever causes the hammer cocking slide 5330 and hammer 5340 to be raised,
thus compressing the power spring 5390; the resulting position is shown
in FIG. 92C. After ensuring the proper positioning of the inserter 5100
with respect to a base (not shown) and/or the skin of a patient, the
trigger is pressed, thereby sending the trigger hammer 5340 downward;
FIG. 92D shows the trigger hammer 5340 in transit. As shown in FIG. 92E,
the trigger hammer 5340 impacts the cartridge bolt 5380, causing it to
travel downward, insert the needle or needles held in the cartridge
housing (not shown) and compress the return spring 5360. FIG. 92F shows
the return spring 5360 in the process of forcing the cartridge bolt 5380
upward; this causes retraction of the cartridge housing and the cartridge
contained therein (not shown) and any associated introduction needles
used.
[0452] Referring now to FIGS. 93A-93C, one embodiment of a temporal
sequence for inserting and securing an infusion device (i.e., cannula or
needle 5010) into a base Y is shown. FIG. 93A shows a base Y with a
locking feature 5210 positioned above a cannula housing 5030. The base Y
is typically positioned against the skin of a patient 5220 when inserting
an infusion device or cannula 5010. FIG. 93B shows a cannula 5010 being
forced through the cannula housing 5030 in the base Y. In this figure, an
introduction needle 5240 is used that traverses a septum (not shown) and
is positioned coaxially in the cannula 5010; a sharp point of the
introduction needle 5240 emerges from the tip (not shown) of the cannula
5010 to help puncture a patient 5220. The resilient locking feature 5210
is pushed aside during insertion of the cannula 5010. FIG. 93C shows the
cannula 5010 fully inserted through the cannula housing 5030 of the base
Y, with the tip of the cannula fully inserted into the patient 5220. The
introduction needle 5240 has been removed and the septum 5060 has
self-sealed to a fluid source or fluid line (not shown). The resilient
locking feature 5210 is engaged with the cannula 5010, thereby preventing
the cannula 5010 from moving in relation to the base Y. Although FIGS.
93A-93C show a cannula 5010, the infusion and sensor assembly shown in
FIG. 86B can be inserted using the locking feature 5210 and method shown
and described in FIGS. 93A-93C.
[0453] Referring now to FIGS. 92G-92H, an inserting cartridge bolt locking
mechanism for use with an inserter, such as the one shown in FIGS.
91A-92F, as 5100 is shown. The cartridge bolt locking mechanism can
function as an interlock to prevent accidental firing while the mechanism
is being cocked. The locking mechanism includes a catch 5420, which when
engaged in a catch recess 5410, prevents downward movement of the
cartridge bolt 5380. As shown in FIG. 92G, when the cocking lever 5145 is
in a closed position, the cocking lever 5145 contacts a catch lever 5440,
which rotates the catch 5420 and prevents the catch 5420 from inserting
into the catch recess 5410. A catch spring 5430, disposed between the
catch 5420 and a catch spring support 5450, is in a compressed
positioned. The cartridge bolt 5380 and trigger hammer 5340 are free to
move. As shown in FIG. 92H, when the cocking lever 5145 is rotated into a
downward position, the catch lever 5440 is released, thereby allowing the
catch spring 5430 to force the catch 5420 to insert into the recess (here
the catch 5420 is shown inside the recess, but the recess is shown in
FIG. 92G as 5410); downward movement of the cartridge bolt 5380 is
thereby prevented. Return of the cocking lever 5145 then returns the
catch 5420 to an unlocked position. The cartridge bolt 5380 is then free
for downward movement in the triggering process.
[0454] Referring now to FIGS. 94A-94C, one embodiment of the process of
mating a cannula 5010, where the cannula is a traditional cannula
requiring an introduction needle (as shown in FIG. 86B) to the base Y and
establishes fluid communication with a fluid line 310 is shown. FIG. 94A
shows a sectional view of a cannula 5010 with two septa: an introduction
needle septum 5062 and a fluid line septum 5270. The introduction needle
septum 5062 seals a passageway 5280 leading to the hollow needle (not
shown, shown in FIG. 94B as 5290) of the cannula 5010. A cannula
introduction needle 5240 is shown positioned above the introduction
needle septum 5062 and just prior to insertion of the introduction needle
5240.
[0455] Referring now to FIG. 94B, the introduction needle 5240 is shown
inserted through the introduction needle septum 5062. A user mates the
cannula 5010 into the base Y, which has an upwardly-pointing rigid,
hollow needle 5290. During insertion of the cannula 5010 into the base Y,
the introduction needle 5240 punctures the fluid line septum 5270 to
establish fluid communication between the fluid line 310 and the
passageway 5280. If the base Y is held against a patient (not shown)
during insertion of the cannula 5010 into the base Y, fluid communication
between the fluid line 310 and the passageway 5280 will be established at
about the same time that the patient's skin is pierced. Referring now to
FIG. 94C, the cannula 5010 is shown, fully inserted into the base Y, with
the introduction needle removed and fluid communication established with
the fluid line 310.
[0456] In an alternate embodiment, insertion of an infusion device and/or
sensor is assisted by a vibration motor coordinated with a fluid delivery
device. Simultaneously with the insertion of the infusion device and/or
sensor, a vibration motor may be activated.
Adhesion
[0457] Referring now to FIG. 95 a top perspective view of one embodiment
of an adhesive patch 3100 for securing an object, such as a fluid
delivery device 10, to the skin of a patient (not shown) is shown.
Although the adhesive patch 3100 is shown in the present shape, other
shapes can be used. Any adhesive patch 3100 that can securely hold a
fluid delivery device can be used.
[0458] Fluid delivery device 10 is securely held under a central region
3130 of the adhesive patch 3100, which is attached to the skin of a
patient by adhesive members 3111.
[0459] These adhesive members 3111 emanate from a central region 3130 in a
radial pattern and are spaced apart from each other by intervening
regions 3121. The radial arrangement of the adhesive members 3111 allows
for attachment of the device 10 to the patient in secure manner. In some
embodiments, the central region 3130 covers the entire device 10,
however, in other embodiments, the central region 3130 covers a portion
of the device 10. The central region 3130 may also include interlocking
attachment features (not shown) that may be held by complementary
interlocking features (not shown) of the device 10. In an alternate
embodiment, the device 10 is securely attached atop the central region
3130 (for example, by an adhesive or interlocking feature).
[0460] The adhesive patch 3100 is typically flat and composed of a
polymeric sheet or fabric. The adhesive patch 3100 may be supplied with
adhesive affixed on one side and protected by a peelable backing such as
a peelable sheet of plastic to which the adhesive will adhere more
loosely that to the patch 3100. The backing may be a single continuous
piece, or may be divided into regions that may be removed separately.
[0461] In an illustrative embodiment, the backing for the central region
3130 may be removable without removing the backing to the adhesive
members 3111. To use the adhesive patch 3100, a user removes the backing
of the central region 3130 and presses the device 10 against the newly
exposed adhesive of the central region to attach the device 10 to the
central region 3130. The user then places the device against the skin,
removes the backing from an adhesive member 3111, affixes the adhesive
member to the skin, and repeats the affixation process with additional
members. A user may affix all of the adhesive members 3111 or only some
of the members, and save additional adhesive members 3111 for application
on another day. Since adhesives typically used for attachment to skin
only remain securely attached for several days, application of sets of
adhesive members 3111 on different days (for example, staggered by 3 to 5
days) should extend the amount of time that the device 10 remains
securely attached to the skin and reduce the of time, expense and
discomfort that is often involved in reapplication of the device. The
varying tabs may have indicia such as different colors or numbers to
indicate to the appropriate time to affix the various adhesive members
3111. The adhesive members 3111 may include perforations to render them
frangible with respect to the central region 3130 so that used adhesive
members may be removed after use. Additional embodiments for extending
the duration during which device 10 remains affixed are discussed above
with reference to FIGS. 79-83.
[0462] FIG. 96 schematically shows a sectional view of a fluid delivery
device 10, with an inserted cannula 5010, held securely under an adhesive
patch 3100. A pad 3220 may be included between the device 10 and a
patient's skin 3250 and allow air to flow to the skin. Air flow to skin
may be increased by the inclusion of passageways 3230 in the pad 3220.
Passageways 3230 may also be formed by using multiple pads that are
spaced apart or by constructing pad 3220 from a highly porous material.
Thus, the pad 3220 can be any shape and size and in some embodiments, the
pad 3220 is made up of a number of separate pieces. Pads 3220 may be
either adhered to the underside of the device 10 during manufacture or
may be adhered to the device 10 by a user. Alternately, the pad 3220 may
be loosely placed onto the skin by a user prior to application of the
adhesive patch 3100. The pad 3220 may include a compliant material, such
as porous polymeric foam.
[0463] FIG. 97 shows an embodiment of the invention that uses a first
adhesive patch 3100 and an additional adhesive patch 3300 to secure a
device (not shown) to a patient. First, a device (not shown) is
positioned for use and secured to the skin (not shown) of a patient with
an adhesive patch 3100 using tab-like adhesive members 3111. The central
region 3130 may be positioned atop (as shown), or secured below, the
device. After a period of time, either prolonged or short, a second
adhesive patch 3300 is positioned so that its central region sits atop
the first adhesive patch 3100 and the second adhesive patch's adhesive
members 3320 are secured to the skin of the patient in the intervening
regions between the first adhesive patch's adhesive members 3111.
Frangible regions may be provided to aid in the removal of loose or
unwanted adhesive members 3111 associated with the earlier placed patch
3100.
[0464] Referring now to both FIGS. 98 and 99, embodiments in which an
adhesive patch 3100 has been divided into at least two smaller adhesive
patches are shown. In these embodiments, the adhesive patch 3100 is
divided into two adhesive patches, 3410 and 3420, each having adhesive
members 3111 radially arranged around a central void 3430. The two
adhesive patches, 3410 and 3420, each span a semi-circle of about
180.degree., but other configurations could be used such as: three
patches, each spanning 120.degree., or four patches each spanning
90.degree.. In some embodiments, the adhesive can include greater than
four patches. The configurations described with respect to these
embodiments follow the formula 360.degree./n where n is the number of
patches. But, in other embodiments, depending on the shape of the device,
the formula shown and described here does not apply. In still other
embodiments, the patches may also cover more than 360.degree., and thus
overlap.
[0465] As shown in the perspective view of FIG. 99, due to the presence of
a central void (not shown, shown in FIG. 98), the central region 3130 is
in the form of a thin strip for adherently positioning along the
perimeter of the device 10. The two patches, 3410 and 3420, together
securely attach the device 10 to the skin (not shown). As in the
embodiment described with reference to FIG. 95, air may flow between the
adhesive members 3111 and under the device 10, especially if passageways
3230 are provided.
[0466] FIG. 100 shows a perspective view of an embodiment that includes
using the multiple adhesive patches to extend the time during which a
device 10 remains adhered to a patient (not shown) before removal. One of
the multiple partial adhesive pads 3420 is removed while the device 10 is
held in place (either by a remaining adhesive patch 3410 and/or by a
user). The removed adhesive patch 3420 is then replaced with a fresh
replacement adhesive patch (not shown). The replacement adhesive patch
may be identical to the removed pad 3420 or may have adhesive members
3111 that are positioned in an alternate configuration to allow adhesion
to the fresh skin between the areas previously covered by adhesive patch
3420. The remaining adhesive patch 3410 may then be replaced in a similar
manner. Indicia such as color coding may be used to indicate the age of
the adhesive patches. The patches may also have a color change mechanism
to indicate that their useful life has expired. Decorative patterns, such
as images and designs, may be included on the patches.
[0467] FIG. 101 schematically shows an embodiment in which multiple
adhesive members 3111 are affixed to a patient 12 and also connected to a
ring like central region 3130 via tethers 3730. The tethers 3730 may be
fibers or cords and may be resilient to decrease the movement of the
device 10 in response to movement of the patient 12. The use of tethers
3730 also increases options available for skin positions of the adhesive
members 3111.
[0468] The adhesive used in the embodiments described in FIGS. 95-101 can
be any effective and safe adhesive available for use on a patient's skin.
However, in one embodiments, the adhesive used is 3M product number 9915,
value spunlace medical non woven tape.
Clamping and Latching
[0469] FIGS. 102A-102C schematically show one mechanism for clamping or
latching together a top portion and a base portion of a fluid delivery
device. Referring first to FIG. 102A, an elevation view of a clamp 6410
is shown. FIG. 102B shows a base portion Y with keyholes 6440 for two
clamps; corresponding keyholes may also be included in the top portion
(not shown). Referring now to FIG. 102C, the top X and the base Y may be
aligned and a clamp 6410 may be inserted through the keyholes (not shown,
shown in FIG. 102B as 6440). Rotating the clamp 6410 by 90.degree. causes
a stud bar 6430 to move into a locking position. Depressing a cam lever
6400 engages a cam 6415, that is hingedly connected to a clamp pin 6420,
to push against the top X. As a result, the top X and the base Y are held
with a clamping force between the cam 6415 and the stud bar 6430. Raising
the cam lever 6400 releases the clamping force and the clamp 6410 may be
rotated by 90.degree. and withdrawn to allow disassembly of the top X and
base Y. In some embodiments, the lever may act as a protective cover for
the top X.
[0470] An alternate embodiment for clamping together the portions of a
device is shown in FIGS. 103A-103D. FIG. 103A shows a perspective view
and FIG. 103B shows a top view of a cam guide 6500. The cam guide 6500
has a keyhole 6440 and sloped surfaces 6510. FIG. 103C shows a cam
follower 6520 having a central pin 6540 with a head 6560 attached at a
first end and a bar 6550 attached to an opposite end. As shown in the
sectional view of FIG. 103D, the cam follower (not shown, shown in FIG.
103C) may be inserted into keyholes (not shown, shown in FIG. 103C) in
the top X, base Y, and cam guide 6500. Movement of a lever 6530 attached
to the central pin 6540 causes rotation of the cam follower (not shown,
shown in FIG. 103C), causing the bar 6550 to travel along the sloped
surface (not shown, shown in FIG. 103C as 6510) and thereby transforming
the rotational force to a force which clamps the base Y and top X firmly
between the cam follower head 6560 and the bar 6550.
Reservoir
[0471] Exemplary embodiments of collapsible reservoirs for holding fluids
are shown in FIGS. 104-106C. The collapsible reservoir has at least one
section or wall that collapses as fluid is withdrawn, thereby maintaining
ambient pressure in its interior. In most embodiments, a sealable port
(e.g., a septum) is included in the reservoir. The port allows the
reservoir to be filled with fluid by a syringe and also, for a leak free
connection to a fluid line. Alternately, an adaptor may be used to
connect the reservoir with the fluid line. Alternately, as shown above
with reference to FIG. 71, a needle may be associated with the reservoir
and a septum may be associated with the terminus of the fluid line. The
reservoir may be constructed of a plastic material known to be
compatible, even if for a very short duration, with the fluid contained
in the reservoir. In some embodiments, the reservoir is entirely
collapsible, i.e., the reservoir does not include any rigid body
surfaces.
[0472] Referring now to FIG. 104 a sectional view of a reservoir 20 is
shown. A cavity 2645 for holding a volume of fluid is formed between a
rigid reservoir body 6200 and a flexible reservoir membrane 6330. The
flexible membrane 6330 is sealingly attached around the periphery of the
cavity 2645 to hold fluid within the cavity 2645. The flexible membrane
6330 imparts collapsibility to the reservoir 20; it deforms inwardly as
fluid is pumped from the cavity 2645.
[0473] A septum 6270 is seated in a neck 6240 extending from the body
6200. The septum 6270 serves as an interface between the cavity 2645 and
a fluid line. In some devices, the fluid line terminates in a needle (not
shown). In these embodiments, the needle may be inserted through the
septum 6270 to access a needle chamber 6280 portion of the cavity 2645.
The septum 6270 location can be maintained by its location between a cap
6250 and a ledge (not shown) formed at the junction of the inner wall
6281 of the needle chamber 6280 and the cap bore 6282. The cap 6250 may
be held by a friction fit within the cap bore 6282. Upon insertion of the
cap 6250, its position is limited by the wall 6261 of the cap bore 6282.
The portion of the cap 6250 closest to the septum 6270 may have a central
aperture to allow insertion of the needle through the cap 6250 and into
the septum 6270. Alternately, the cap 6250 may be punctured by the
needle.
[0474] FIG. 105 shows a perspective view of the inside of the collapsible
reservoir 20. A rim 6230 allows attachment of the flexible reservoir
membrane, which may be attached by welding, clamping, adhering, or other
suitable method to create a fluid tight seal. A guard structure 6290 may
be included to allow fluid to flow to or from the cavity 2645, but
prevents a needle from entering the cavity, thereby preventing it from
possible puncture of the reservoir membrane.
[0475] FIGS. 106A-106C show an alternate embodiment of a reservoir in
which a cap 6250 sealingly attaches a septum 6270 to a wall 6320 of a
reservoir. The wall 6320 could be constructed, for example, from a
flexible sheet such as PVC, silicone, polyethylene or from an ACLAR film.
In some embodiments, the wall 6320 may be constructed from a heat
formable polyethylene laminate formed with an ACLAR firm. The flexible
sheet is compatible with the fluid. The wall may be attached to a rigid
housing, or part of a flexible plastic pouch, such as may be formed by
folding and welding the ends of a plastic sheet. FIG. 106A shows the cap
6250 sealed to a wall 6320 via a circular fin 6350. The septum 6270 may
be inserted into a turret 6340 that protrudes from the cap 6250. The
turret 6340 may be constructed from a material that is deformable at high
temperature, but rigid at room temperature, for example, low density
polyethylene. Referring now to FIG. 106B, a hot press 6310, or another
apparatus or process for melting, is used to melt or bend the turret 6340
over the septum 6270. Referring now to FIG. 106C, the septum 6270 is
shown immobilized to the cap 6250.
[0476] Certain fluids are sensitive to storage conditions. For example,
insulin may be somewhat stable in the glass vials in which it is
typically shipped, but may be unstable when left in prolonged contact
with certain plastics. In some embodiments, the reservoir 20 is
constructed of such a plastic. In this case, the reservoir 20 may be
filled with fluid just prior to use so that the fluid and plastic are in
contact for a shorter period time.
Reservoir Filling Station
[0477] Referring now to FIG. 107 a reservoir filling station 7000 for
filling a reservoir 20 with a fluid is shown. The fluid may be withdrawn
from its original container with a syringe 7040 and introduced into the
reservoir 20 by using the fill station 7000. The fill station 7000 may
include a substantially rigid fill station base 7010 hinged to a
substantially rigid fill station cover 7020 via a hinge 7030.
Accordingly, the station 7000 may be opened and closed to accept and hold
the reservoir 20. A needle 7050 attached to the syringe 7040 may then be
inserted through a filling aperture 7060 in the cover 7020, and through
the reservoir septum 6270. Since the fill station cover 7020 is rigid, it
establishes a limit of travel upon the syringe 7040 and therefore
controls the depth of needle 7050 penetration into the reservoir 20 to
discourage puncture of the underside of the reservoir 20. A leg 7070
holds the station 7000 in a tilted position when supported on a surface.
Since the station 7000 is tilted, as the fluid is injected from the
syringe 7040 into the reservoir 20, air will tend to rise upwardly toward
the septum 6270. After the syringe 7040 injects the desired amount of
fluid into the reservoir 20, the syringe 7040 may be used to remove any
remaining air in the reservoir 20. Since the fill station base 7010 and
cover 7020 are rigid, the flexible reservoir 20 generally cannot be
distended past a fixed volume and overfilling of the reservoir 20 is
discouraged. The base 7010 and cover 7020 may be locked together with a
clasp, or a heavy cover may be used to further discourage overexpansion
and overfilling of the reservoir.
[0478] Referring now to FIGS. 108A and 108B, an alternate embodiment of
the reservoir filling station 7000 is shown. In this embodiment, the
reservoir (not shown) is placed in the space between the cover 7020 and
the base 7010. A hinge 7030 attached the cover 7020 and the base 7010. As
shown in FIG. 108B, the reservoir (not shown) is inside, and a syringe
(not shown) needle (not shown) is inserted into the filling aperture
7060. The filling aperture 7060 connects directly to the reservoir's
septum (not shown). A viewing window 7021 indicates the fluid line in
terms of the volume of fluid that has been injected into the reservoir.
[0479] A fluid delivery system typically includes a fluid delivery device
and an external user interface, although in some embodiments a complete
or partial internal user interface is included in the device. The device
can be any device as described herein or a variation thereof.
[0480] FIG. 109A shows a flow diagram of a data acquisition and control
scheme for an exemplary embodiment of a fluid delivery system. A patient
or caregiver utilizes an external user interface 14 which is typically a
base station or hand held unit housed separately from the fluid delivery
device 10. In some embodiments, the user interface 14 is integrated with
a computer, cell phone, personal digital assistance, or other consumer
device. The user interface assembly may be in continuous or intermittent
data communication with the fluid delivery device 10 via wireless radio
frequency transmission (for example, via LF, RF, or standard wireless
protocols such as "Bluetooth") but could also be connected via data
cable, optical connection or other suitable data connection. The external
user interface 14 communicates with a processor 1504 to input control
parameters such as body mass, fluid dose ranges or other data and
receives status and function updates such as the presence of any error
conditions resulting from occluded flow, leaks, empty reservoir, poor
battery condition, need for maintenance, passage of an expiration date,
total amount of fluid delivered or remaining or unauthorized disposable
component. The interface 14 may transmit error signals to a patient's
guardian or medical professional through a telephone, email, pager,
instant messaging, or other suitable communication medium. A reservoir
actuator assembly 1519 includes an actuator 1518 and a reservoir 1520.
The dispensing assembly 120 transmits data related to flow through the
flow line to the processor 1504. The processor 1504 uses the flow data to
adjust the action of the actuator 1518 in order to increase or decrease
flow from the reservoir pump assembly 1519 to approximate the desired
dosage and timing. Optionally, a feedback controller 1506 of the
processor 1504 may receive data related to the operation of the reservoir
pump assembly 1519 for detection of conditions such as open or short
circuit faults, or actuator temperature.
[0481] FIG. 109B shows an alternate embodiment of the flow diagram in FIG.
102A. In this embodiment, the lack of dispensing assembly/sensor removes
the feedback based on volume of fluid.
[0482] Referring now to FIG. 110A, a flow chart of one embodiment of the
overall operation of a fluid delivery device within the fluid delivery
system is shown. A user starts 2800 the system using a switch or from an
external user interface (step 2800). The system initializes by loading
default values, running system tests (step 2810) and obtaining variable
parameters such as desired basal and bolus doses. Variable parameters may
be selected by the user using the user interface, either using an input
device such as a touch screen on the user interface or by loading saved
parameters from memory (step 2820). The actuator timing is calculated
based on the predicted or calibrated performance of the fluid delivery
device (step 2830). The dispensing assembly is initiated at the start of
the fluid delivery device activation (step 2840). Dispensing assembly
data collection 2835 continues through actuation and delivery. During
operation, the dispensing assembly provides data that allows
determination of the cumulative volume of fluid that has flowed through
the dispensing chamber as well as the flow rate for one or more time
periods. The fluid delivery device is activated to cause fluid to flow
through the flow line into the dispensing chamber (step 2840). Drug flows
from the dispensing chamber to the patient at a rate determined by the
impedance of the exit, and in some embodiments, the force exerted by a
diaphragm spring, and the force exerted by the pumping assembly (step
2860). The system will stop and the user will be notified if there is a
user stop interrupt, a low flow condition, the reservoir is determined to
be empty based on predicted cumulative flow or detection by an additional
reservoir volume sensor, or any other alarm operation either part of the
system or user specified (step 2870). If there is no user stop signal,
determination of an empty reservoir or another alarm indicator, then a
check is made to determine if an adjustment to the actuator timing is
needed due to a deviation between the actual and desired flow rate or due
to a change in desired flow rate by the user (step 2880). If no
adjustment is needed, the process returns to step 2840. If an adjustment
is needed, the process instead returns to step 2830.
[0483] Referring now to FIG. 110B, a flow chart of another embodiment of
the overall operation of a fluid delivery device within the fluid
delivery system is shown. In this embodiment, the decision to adjust the
actuation timing is made based on a user inputted variation or on another
feedback. In this embodiment, a dispensing assembly with a sensor for
determining volume is not included; thus the adjustments are made based
on alternative feedback mechanisms.
Wireless Communication
[0484] Referring now to FIG. 111 a layout of an embodiment using coils for
inductive charging and wireless communication in a fluid delivery system
is shown. As previously described, the user interface assembly 14 can be
embodied as a hand held user interface assembly 14 that wirelessly
communicates with the fluid delivery device 10. A secondary coil (i.e. a
solenoid) 3560 may be employed in the fluid delivery device 10 as a
wireless transceiver antenna in conjunction with wireless controller
3580. The secondary coil 3560 may also serve as a secondary transformer
for recharging the device battery 3150, at least partially, in
conjunction with a battery recharging circuit 3540. In this embodiment,
the user interface assembly 14 contains a primary coil 3490 for
inductively coupling energy to a secondary coil 3560. When the user
interface assembly 14 is in close proximity to the fluid delivery device
10, the primary coil 3490 energizes the secondary coil 3560. The
energized secondary coil 3560 powers a battery recharging circuit 3540
for recharging the battery 3150 in the fluid delivery device 10. In some
embodiments, the primary coil 3490 also functions as an antenna to
transmit and receive information from the fluid delivery device 10 in
conjunction with a wireless controller 3470.
[0485] Referring now to FIG. 112, some embodiments include long range
wireless communication (e.g., 20-200 ft or more) hardware in the fluid
delivery device 10. Thus, the fluid delivery device 10 could be monitored
from a distance.
[0486] Still referring to FIG. 112, an intermediate transceiver 6600,
typically carried by the patient, can provide the benefits of long range
communication without increasing the size, weight and power consumption
of the fluid delivery device 10. As shown in the data flow diagram of
FIG. 112, a wearable fluid delivery device 10 uses short range hardware
and associated software to transmit data to, or receive data from, the
intermediate transceiver 6600. For example, the device 10 may be equipped
to transmit data over distances of approximately 3-10 ft. The
intermediate transceiver 6600 may then receive this data and use long
range hardware and software to relay this data to a user interface
assembly 14. The intermediate transceiver 6600 may also accept control
signals from the user interface assembly 14 and relay these signals to
the device 10. Optionally, the user interface assembly 14 may also be
capable of communicating directly with the fluid delivery device 10, when
in range. This direct communication may be configured to occur only when
the intermediate transceiver 6600 is not detected, or alternatively,
anytime the user interface assembly 14 and the fluid delivery device are
within range of each other.
[0487] Many types of data may be transmitted in this way, which include,
but are not limited to:
Data related to the timing of pump actuation and volume measurements and
other data from the dispensing assembly may be transmitted to the
intermediate transceiver 6600 and, in turn, to the user interface
assembly 14; Alarm signals may be transmitted to and from the fluid
delivery device 10; Signals to confirm the receipt of data may be
transmitted from the user interface 14 to the intermediate transceiver
6600 and from the intermediate transceiver 6600 to the fluid delivery
device 10; Control signals to change the operating parameters of the
device 10 may be transmitted from the user interface assembly 14 to the
fluid delivery device 10 using the intermediate transceiver 6600.
[0488] Referring now to FIG. 113, a plan diagram of a specific embodiment
of an intermediate transceiver 6600 is shown. A short range transceiver
6610 communicates with a nearby fluid delivery device. The short range
transceivers of the device and the intermediate transceiver 6600 may
communicate using one or more of many protocols and transmission
frequencies known to be useful for short range communication, e.g. radio
frequency transmission. Data received by the intermediate transceiver
6600 is conveyed to a microprocessor 6630, which may store the data in
memory 6620 (e.g., a flash memory chip), and retrieve the data as needed.
The microprocessor 6630 is also connected to a long range transceiver
6640, which is in data communication with the user interface. For
example, the intermediate transceiver 6600 and user interface assembly
may operate on the Bluetooth standard which is a spread-spectrum protocol
that uses a radio frequency of about 2.45 MHz and may operate over a
distance of up to about 30 feet. The Zigbee standard is an alternative
standard that operates in the ISM bands around 2.4 GHz, 915 MHz, and 868
MHz. However, any wireless communication could be used.
[0489] Optionally, the microprocessor 6630 analyzes received data to
detect the presence of malfunctions or maintenance needs associated with
the device. Some examples of fault conditions include, but are not
limited to:
a lack of received data for a time period that exceeds a set limit; a
lack of data receipt confirmation signal from the device or the user
interface assembly; an overflow or near overflow condition of the
appliance memory 6620; low power; overly high, low or improperly timed
volume measurements received from the fluid delivery device 10.
[0490] Based on this fault analysis, the microprocessor 6630 may trigger
an alarm 6650 (e.g., a bell or buzzer). The microprocessor 6630 may also
communicate an alarm condition to a remote device. The remote device may
be, for example, the user interface assembly using the long range
transceiver 6640, the fluid delivery device 10 using the short range
transceiver, or both the user interface assembly and fluid delivery
device. Upon receiving an alarm signal, the user interface assembly may
then relay the alarm signal over longer distances to a medical
professional or patient guardian (e.g., by pager or telephone call or
other methods of communication).
[0491] The power supply 6670 may be rechargeable, and may store sufficient
energy to operate continuously for a period of time, for example, at
least 10 hours. However, the operation time will vary based on use and
device. The size of the fluid delivery device may be reduced so that it
may easily be carried in a pocket, purse, briefcase, backpack or the
like. One embodiment of the device includes a means to withstand routine
shocks or spills. Additional features may be included in some
embodiments, including, but not limited to, decorative features, or any
of a wide range of consumer electronics capabilities such as the ability
to play video games, send and receive instant messages, watch digital
video, play music, etc. Third party controls may be included to remove or
limit the use of such functions during some or all hours of the day.
Alternately, the device may be as small and simple as possible, and only
serve to repeat short range signals over a longer range. For example, the
memory and analysis capability may be omitted.
[0492] Referring now to FIG. 114, a data flow diagram for an embodiment of
the system is shown. An intermediate transceiver 6600 is shown operating
as a universal patient interface that engages in short range
communication with multiple devices and relays information from those
devices over a long range to one or more user interfaces associated with
those devices. Examples of devices include wearable, implantable or
internal medical devices including a fluid delivery system, a glucose
sensor, a knee joint with an integrated strain sensor, an instrumented
enteric probe in pill form, a defibrillator, a pacemaker, and other
wearable therapeutic delivery devices. Since different types of devices
and devices from different manufacturers may utilize differing short
range communication standards and frequencies, the intermediate
transceiver 6600 may include hardware (e.g., multiple antennas and
circuitry), and software to support multiple protocols.
Battery Recharger
[0493] Referring now to FIGS. 115 and 116. One embodiment of an apparatus
is shown for recharging the battery 7100. In FIG. 15, the top,
non-disposable portion of a fluid delivery device 2620 is shown
disconnected from the base, disposable portion of a fluid delivery
device. The battery recharger 7100 is used to recharge the battery (not
shown) in the top 2620. In FIG. 116, the top 2620 is shown on the battery
recharger 7100. The latches 6530 are shown closed, connecting the top
2620 to the battery recharger 7100. Thus, the latch 6530 used to connect
a top portion 2620 to a base portion (not shown) is also used to connect
the top 2620 to the battery recharger 7100. Docking may establish a
direct power connection, or power may be transferred by way of inductive
coupling. Also, in some embodiments of the system, the patient employs
multiple non-disposable portions 2620 in rotation; i.e., recharging one
non-disposable portion 2620, while using a second non-disposable portion
(not shown).
[0494] The various embodiments described herein include different types
and configurations of elements such as, for example, pump architectures,
pump actuators, volume sensors, flow restrictors, reservoirs (and
reservoir interfaces), sharps inserters, housings, latching mechanisms,
user interfaces, on-board peripherals (e.g., controllers, processors,
power sources, network interfaces, sensors), and other peripherals (e.g.,
hand-held remote controller, base station, repeater, filling station). It
should be noted that alternative embodiments may incorporate various
combinations of such elements. Thus, for example, a pump architecture
described with reference to one embodiment (e.g., the pump shown and
described with reference to FIGS. 15A-15D) may be used with any of the
various configurations of pump actuators (e.g., single shape-memory
actuator with single mode of operation, single shape-memory actuator with
multiple modes of operation, multiple shape-memory actuators of the same
size or different sizes), and may be used in devices with various
combinations of other elements (or absence of other elements) and/or any
of the various flow restrictors.
[0495] Furthermore, while various embodiments are described herein with
reference to a non-pressurized reservoir, it should be noted that a
pressurized reservoir may be used in certain embodiments or under certain
conditions (e.g., during priming and/or air purging). Among other things,
a pressurized reservoir might facilitate filling of the pump chamber, for
example, following retraction of the pump actuation member 54 shown and
described with reference to FIGS. 15A-15D.
[0496] Additionally, while various embodiments are described herein with
reference to a pump motor disposed in a reusable portion of a housing, it
should be noted that a pump and/or a pump motor may alternatively be
situated in the disposable portion, for example, along with various
components that come into contact with the fluid. As with some of the
other motors described herein, a motor disposed in the disposable portion
may include one or more shape-memory actuators.
[0497] It should be noted that section headings are included for
convenience and are not intended to limit the scope of the invention.
[0498] In various embodiments, the herein disclosed methods including
those for controlling and measuring flow of a fluid and for establishing
communication amongst linked components may be implemented as a computer
program product for use with a suitable controller or other computer
system (referred to generally herein as a "computer system"). Such
implementations may include a series of computer instructions fixed
either on a tangible medium, such as a computer readable medium (e.g., a
diskette, CD-ROM, ROM, EPROM, EEPROM, or fixed disk) or transmittable to
a computer system, via a modem or other interface device, such as a
communications adapter connected to a network over a medium. The medium
may be either a tangible medium (e.g., optical or analog communications
lines) or a medium implemented with wireless techniques (e.g., microwave,
infrared or other transmission techniques). The series of computer
instructions may embody desired functionalities previously described
herein with respect to the system. Those skilled in the art should
appreciate that such computer instructions can be written in a number of
programming languages for use with many computer architectures or
operating systems.
[0499] Furthermore, such instructions may be stored in any memory device,
such as semiconductor, magnetic, optical or other memory devices, and may
be transmitted using any communications technology, such as optical,
infrared, acoustic, radio, microwave, or other transmission technologies.
It is expected that such a computer program product may be distributed as
a removable medium with accompanying printed or electronic documentation
(e.g., shrink wrapped software), preloaded with a computer system (e.g.,
on system ROM, EPROM, EEPROM, or fixed disk), or distributed from a
server or electronic bulletin board over the network (e.g., the Internet
or World Wide Web). Of course, some embodiments of the invention may be
implemented as a combination of both software (e.g., a computer program
product) and hardware. Still other embodiments of the invention are
implemented as entirely hardware, or substantially in software (e.g., a
computer program product).
[0500] It should be noted that dimensions, sizes, and quantities listed
herein are exemplary, and the present invention is in no way limited
thereto. In an exemplary embodiment of the invention, a patch-sized fluid
delivery device may be approximately 6.35 cm (.about.2.5 in) in length,
approximately 3.8 cm (.about.1.5 in) in width, and approximately 1.9 cm
(.about.0.75 in) in height, although, again, these dimensions are merely
exemplary, and dimensions can vary widely for different embodiments.
[0501] While the principles of the invention have been described herein,
it is to be understood by those skilled in the art that this description
is made only by way of example and not as a limitation as to the scope of
the invention. Other embodiments are contemplated within the scope of the
present invention in addition to the exemplary embodiments shown and
described herein. Modifications and substitutions by one of ordinary
skill in the art are considered to be within the scope of the present
invention.
* * * * *