Infusion medium delivery device and method with drive device for driving plunger in reservoir

• US 20080051727A1
• Filed: 09/01/2006
• Published: 02/28/2008
• Est. Priority Date: 08/23/2006
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Moberg, Sheldon B., Kavazov, Julian D., Chong, Colin A., Hanson, Ian B., Griffin, Christopher G., Mounce, R. Paul, Holt, Mark D., Tieck, Ruth Marie, Bente, Paul F.
• Granted Patent: US 8,512,288 B2
• Time in Patent Office: Days
• US Class Current: 604/207
• CPC Class Codes: A61M 2005/14252 with needle insertion means
• CPC Class Codes: A61M 2005/14268 with a reusable and a disposable component
• CPC Class Codes: A61M 2205/0266 Shape memory materials
• CPC Class Codes: A61M 2205/103 rotating
• CPC Class Codes: A61M 5/1413 Modular systems comprising interconnecting elements
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/148 flexible, e.g. independent bagsA61M5/155 takes precedence

Abstract

A delivery device includes a durable housing portion and a separable disposable portion that selectively engage and disengage from each other. The disposable housing portion secures to the patient-user and may be disposed of after it has been in use for a prescribed period. Components that normally come into contact with a patient-user or with infusion medium are supported by the disposable housing portion, while the durable housing portion supports other components such as electronics and a drive device. A reservoir is supported by the disposable housing portion and has a moveable plunger that operatively couples to the drive device, when the disposable and durable housing portions are engaged.

Claims

1. A delivery device for delivering an infusion medium to a user, the device comprising:

a disposable housing portion adapted to be carried by a user;

a durable housing portion configured to be selectively engaged with and disengaged from the disposable housing portion to allow disposal of the disposable housing portion without disposing of the durable housing portion, the durable housing portion having an enclosed interior volume;

a reservoir having an interior for containing a fluidic medium and a piston plunger moveable within the interior of the reservoir, wherein the reservoir is supported by the disposable housing portion;

a lead shaft supported for rotation by the durable housing portion, the lead shaft having a threaded portion located external to the enclosed interior volume of the durable housing portion for engaging the piston plunger and moving the piston plunger with rotation of the lead shaft when the durable housing portion is engaged with the disposable housing portion, the lead shaft having a connection portion located within the enclosed interior volume of the durable housing portion, wherein the lead shaft extends through an aperture in the durable housing portion; and

a drive device operatively connected to the connection portion of the lead shaft, to selectively rotate the lead shaft.

2. A delivery device according to claim 1, further comprising a seal adjacent to the aperture in the durable housing portion, to seal the aperture through which the lead shaft extends.

3. A delivery device according to claim 1, further comprising electrical control circuitry contained in the durable housing portion, wherein the electrical control circuitry controls the delivery of infusion medium from the reservoir to the user when the durable housing portion and the disposable housing portion are engaged.

4. A delivery device according to claim 1, wherein the disposable housing portion comprises a base portion having a bottom surface and an adhesive material on the bottom surface for securing the disposable housing portion to the skin of the user.

5. A delivery device according to claim 1, wherein the reservoir includes a septum that may be pierced by a hollow needle for providing a fluid flow path from the interior of the reservoir to the hollow needle.

6. A delivery device according to claim 1, wherein the piston plunger comprises a plunger head disposed within the interior of the reservoir, an engagement portion located outside of the reservoir for engaging the threaded portion of the lead shaft when the durable housing portion and the disposable housing portion are engaged, and a piston shaft extending from the plunger head to the engagement portion.

7. A delivery device according to claim 6, wherein the engagement portion of the piston plunger comprises a threaded surface having threads configured to operatively engage threads on the threaded portion of the lead shaft when the durable housing portion and the disposable housing portion are engaged.

8. A delivery device according to claim 7, wherein the lead shaft has a longitudinal axis, and wherein the threaded surface of the engagement portion of the piston plunger is curved at least partially around the longitudinal axis of the lead shaft, upon the engagement portion of the piston plunger being operatively engaged with the lead shaft.

9. A delivery device according to claim 6, wherein the plunger head disposed within the interior of the reservoir has an outer peripheral surface and at least one seal arranged around the outer peripheral surface, for sealing the interior of the reservoir.

10. A delivery device according to claim 1, wherein the piston plunger comprises a plunger head disposed within the interior of the reservoir, the plunger head having an outer peripheral surface and at least one seal arranged around the outer peripheral surface, for sealing the interior of the reservoir.

11. A delivery device according to claim 1, wherein the drive device is located within the enclosed interior volume of the durable housing portion.

12. A delivery device according to claim 1, further comprising an anti-rotation structure to inhibit the piston plunger from rotating within the reservoir.

13. A delivery device according to claim 12, wherein the reservoir has an interior surface and wherein the anti-rotation structure comprises at least one projection extending from one of the piston plunger and the interior surface of the reservoir and at least one channel provided in the other one of the piston plunger and the interior surface of the reservoir, wherein the at least one projection is configured to extend at least partially into the at least one channel.

14. A delivery device according to claim 1, wherein:

the piston plunger comprises a plunger head disposed within the interior of the reservoir, and a piston shaft coupled to the plunger head, the piston shaft having a longitudinal axis and a threaded portion extending along the longitudinal axis at least partially outside of the reservoir; and

the threaded portion of the lead shaft comprises a threaded head arranged to engage the threaded portion of the piston shaft, when the durable housing portion and the disposable housing portion are engaged.

15. A delivery device according to claim 1, wherein the drive device comprises:

an escapement wheel supported for rotation, the escapement wheel having a plurality of teeth, the escapement wheel being operatively connected to rotate the lead shaft with rotation of the escapement wheel;

a drive pawl supported for linear movement between a start position and an end position and having a drive surface arranged to engage a tooth of the escapement wheel and rotate the escapement wheel in a first direction as the drive pawl moves between the start and end positions; and

an actuator operatively connected to the drive pawl, for selectively moving the drive pawl from the start position to the end position.

16. A delivery device according to claim 15, wherein the drive device further comprises a second pawl having a surface for contacting a tooth of the escapement wheel and inhibiting rotation of the escapement wheel in a second direction opposite to the first direction.

17. A delivery device according to claim 15, wherein the actuator comprises a linear actuator or a bender actuator.

18. A delivery device according to claim 15, wherein the escapement wheel is operatively connected to the lead shaft through at least one linkage gear.

19. A delivery device according to claim 15, further comprising a bias member for biasing the drive pawl to return the drive pawl to the start position, once the drive pawl is moved to the end position by the actuator.

20. A delivery device according to claim 1, wherein the drive device comprises:

a drive wheel supported for rotation, the drive wheel having a plurality of teeth, the drive wheel being operatively connected to rotate the lead shaft with rotation of the drive wheel;

an escapement wheel supported for rotation and having one or more teeth for engaging one or more corresponding teeth on the drive wheel and rotating the drive wheel less than 360 degrees for each 360 degree rotation of the escapement wheel; and

a drive motor coupled to the escapement wheel to selectively rotate the escapement wheel.

21. A method of assembling a delivery device for delivering an infusion medium to a user, the method comprising:

providing a disposable housing portion adapted to be carried by a user;

configuring a durable housing portion to be selectively engaged with and disengaged from the disposable housing portion to allow disposal of the disposable housing portion without disposing of the durable housing portion, the durable housing portion having an enclosed interior volume;

supporting a reservoir by the disposable housing portion, the reservoir having an interior for containing a fluidic medium;

supporting a piston plunger for movement within the interior of the reservoir;

supporting a lead shaft by the durable housing portion for rotation, including arranging a threaded portion of the lead shaft external to the enclosed interior volume of the durable housing portion, arranging a connection portion of the lead shaft within the enclosed interior volume of the durable housing portion, and extending the lead shaft through an aperture in the durable housing portion;

engaging the threaded portion of the lead shaft with the piston plunger for moving the piston plunger with rotation of the lead shaft when the durable housing portion is engaged with the disposable housing portion; and

operatively connecting a drive device to the connection portion of the lead shaft, to selectively rotate the lead shaft.

22. A method according to claim 21, further comprising locating a seal adjacent to the aperture in the durable housing portion, to seal the aperture through which the lead shaft extends.

23. A method according to claim 21, further comprising supporting electrical control circuitry in the durable housing portion, wherein the electrical control circuitry controls the delivery of infusion medium from the reservoir to the user when the durable housing portion and the disposable housing portion are engaged.

24. A method according to claim 21, further comprising providing an anti-rotation structure to inhibit the piston plunger from rotating within the reservoir.

25. A device for conveying a fluidic medium to or from a user, the device comprising:

a first housing portion adapted to be carried by a user;

a second housing portion configured to be selectively engaged with and disengaged from the first housing portion, the second housing portion having an enclosed interior volume;

a reservoir having an interior for containing a fluidic medium and a piston plunger moveable within the interior of the reservoir, wherein the reservoir is supported by the first housing portion;

a lead shaft supported for rotation by the second housing portion, the lead shaft having a threaded portion located external to the enclosed interior volume of the second housing portion for engaging the piston plunger and moving the piston plunger with rotation of the lead shaft when the second housing portion is engaged with the first housing portion, the lead shaft having a connection portion located within the enclosed interior volume of the second housing portion, wherein the lead shaft extends through an aperture in the second housing portion; and

a drive device operatively connected to the connection portion of the lead shaft, to selectively rotate the lead shaft.

26. A device according to claim 25, further comprising a seal adjacent to the aperture in the second housing portion, to seal the aperture through which the lead shaft extends.

27. A device according to claim 25, further comprising electrical control circuitry contained in the second housing portion, wherein the electrical control circuitry controls the delivery of infusion medium from the reservoir to the user when the second housing portion and the first housing portion are engaged.