Dispensing fluid from an infusion pump system

• US 20070073228A1
• Filed: 09/18/2006
• Published: 03/29/2007
• Est. Priority Date: 09/26/2005
• Status: Active Grant

• Current Assignee: Bigfoot Biomedical, Inc. (Abbott Laboratories)
• Original Assignee: M2 Group Holdings Inc (Abbott Laboratories)
• Inventors: Wenger, Mitchell, Kirschen, Todd, Mernoe, Morten, Causey, James
• Granted Patent: US 7,534,226 B2
• Time in Patent Office: Days
• US Class Current: 604/131
• CPC Class Codes: A61M 2005/14506 mechanically driven, e.g. spring or clockwork
• CPC Class Codes: A61M 2005/31518 designed to reduce the overall size of an injection device, e.g. using flexible or pivotally connected chain-like rod members
• CPC Class Codes: A61M 2205/8212 with means or measures taken for minimising energy consumption
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/1454 spring-actuated, e.g. by a clockwork
• CPC Class Codes: A61M 5/14566 with a replaceable reservoir for receiving a piston rod of the pump

Abstract

Some embodiments of an infusion pump device may include a drive system that accurately and incrementally dispenses fluid from the pump device in a controlled manner. Particular embodiments of the drive system may include a rotational motor that is coupled to a string member, which is used to adjust a pawl relative to a ratchet body. In such circumstances, the drive system can provide a reliable and compact infusion pump device that accurately dispenses the desired volume of fluid.

Claims

1. A medical infusion pump system, comprising:

a pump device having a drive system to cause dispensation of a medicine, the drive system including;

a pawl that is adjustable relative to a ratchet body, the pawl engaging one or more teeth of the ratchet body to incrementally advance the ratchet body;

a string member coupled to the pawl, the string member being arranged in a loop around two or more guide structures; and

a rotational motor coupled to the string member so that rotation by the motor causes the string member to adjust the pawl relative to the ratchet body.

2. The medical infusion pump system of claim 1, further comprising a removable controller device that is mechanically and electrically connectable to the pump device.

3. The medical infusion pump system of claim 2, wherein removable controller device comprises a user interface that provides information to a user when the controller device is connected to the pump device.

4. The medical infusion pump system of claim 2, wherein the pump device further comprises a housing that defines a cavity to receive a medicine cartridge, the pump device housing defining at least one portion that mates with the removable controller device.

5. The medical infusion pump system of claim 2, wherein removable controller device controls the rotational motor to alternate between rotation in a first rotational direction and rotation in a second rotational direction.

6. The medical infusion pump system of claim 1, wherein the pawl is adjustable from a reset position to a forward position to incrementally advance the ratchet body.

7. The medical infusion pump system of claim 6, wherein the drive system further includes a bias member coupled to the pawl to drive the pawl toward the forward position and incrementally advance the ratchet body.

8. The medical infusion pump system of claim 7, wherein the drive system further includes a flexible piston rod that is advanced in a longitudinal direction by an incremental distance in response the incremental advancement of the ratchet body.

9. The medical infusion pump system of claim 7, wherein the string member is twisted by the one or more rotations of the rotational motor and thereby urges the pawl member toward the reset position.

10. The medical infusion pump system of claim 9, wherein the loop is shortened in length when the string member is twisted by the one or more rotations of the rotational motor.

11. The medical infusion pump system of claim 1, wherein the pawl comprises a pivotable body and the ratchet body comprises a ratchet wheel.

12. The medical infusion pump system of claim 1, wherein at least one of the guide structures is fixedly positioned relative to the rotational motor.

13. The medical infusion pump system of claim 12, wherein at least one of the guide structures is fixedly positioned relative to the pawl.

14. The medical infusion pump system of claim 1, wherein one or more rotations by the motor causes the string member to apply a tension force to the pawl.

15. The medical infusion pump system of claim 14, wherein one or more rotations by the motor causes a portion of the string member between the rotational motor and the guide structures to be twisted.

16. The medical infusion pump system of claim 1, wherein the string member comprises a flexible member capable of transmitting a tension force.

17. The medical infusion pump system of claim 16, wherein the flexible member is selected from the group consisting of a braided filament structure, a monofilament string structure, and a tape structure.

18. A medical infusion pump system, comprising:

a pump device having a drive system to cause dispensation of a medicine, the drive system including;

a pawl that is adjustable relative to a ratchet body, the pawl engaging one or more teeth of the ratchet body to incrementally advance the ratchet body;

a flexible member coupled to the pawl;

a spindle coupled to the flexible member; and

a rotational motor coupled to the spindle so that rotation by the motor causes the flexible member to wind or unwind around spindle to thereby adjust the pawl relative to the ratchet body.

19. The medical infusion pump system of claim 18, wherein the flexible member comprises a braided filament structure capable of transiting a tension force.

20. The medical infusion pump system of claim 18, wherein the flexible member comprises a flexible tape structure capable of transmitting a tension force.

21. The medical infusion pump system of claim 18, wherein the spindle is arranged coaxially with a rotational shaft of the motor.

22. The medical infusion pump system of claim 18, wherein one or more rotations by the motor causes the flexible member to apply a tension force to the pawl.

23. The medical infusion pump system of claim 22, wherein one or more full rotations by the motor in a first rotational direction causes one or more full windings of the flexible member around the spindle, the one or more full windings of the flexible member adjusting the pawl to engage a new tooth of the ratchet body.

24. The medical infusion pump system of claim 18, further comprising a removable controller device that is mechanically and electrically connectable to the pump device.

25. The medical infusion pump system of claim 24, wherein the removable controller device comprises a user interface that provides information to a user when the controller device is connected to the pump device.

26. The medical infusion pump system of claim 18, wherein the drive system further includes a bias member coupled to the pawl to drive the pawl from a reset position toward a forward position so as to incrementally advance the ratchet body.

27. The medical infusion pump system of claim 26, wherein the drive system further includes a flexible piston rod that is advanced in a longitudinal direction by an incremental distance in response the incremental advancement of the ratchet body.

28. The medical infusion pump system of claim 26, wherein the flexible member is wound around the spindle member by the one or more full rotations of the rotational motor and thereby urges the pawl member toward the reset position.

29. A medical infusion pump system, comprising:

a pump device including;

a housing that defines a cavity to receive a medicine, and

a drive system to cause dispensation of the medicine when the medicine is received in the cavity, the drive system comprising a rotational motor and a string member coupled to the motor, the string member comprising braided filaments; and

a controller device that is electrically connectable to the pump device to control operation of the drive system.

30. The medical infusion pump system of claim 29, wherein the string member comprises braided filaments capable of enduring repeated twisting cycles of the string member.

31. The medical infusion pump system of claim 29, wherein the string member comprises braided filaments that are braided around a centrally disposed thin wire.

32. The medical infusion pump system of claim 29, wherein the drive system further includes:

a pawl coupled to the string member, the pawl being adjustable relative to a ratchet body, the pawl engaging one or more teeth of the ratchet body to incrementally advance the ratchet body; and

the rotational motor being coupled to the string member so that rotation by the motor causes the string member to adjust the pawl relative to the ratchet body.

33. A method for dispensing medicine from an infusion pump system, comprising:

rotating a motor one or more full rotations in a first rotational direction to unwind a string member from a spindle and thereby adjust a ratchet mechanism coupled to a piston rod, wherein the adjustment of the ratchet mechanism incrementally advances the piston rod in a forward direction to force medicine from a wearable medicine dispenser device;

continuing to rotate the motor in the first rotational direction so that the string member winds around the spindle and thereby applies a tension force to reset the ratchet mechanism; and

in a next dispensing cycle, rotating the motor one or more full rotations in an opposite, second rotational direction to unwind the string member from the spindle and thereby adjust the ratchet mechanism coupled to the piston rod, wherein the adjustment of the ratchet mechanism incrementally advances the piston rod in the forward direction to force medicine from the wearable medicine dispenser device.

34. The method of claim 33, wherein the spindle is arranged coaxially with a rotational shaft of the motor.

35. The method of claim 33, wherein the ratchet mechanism comprises a pawl that is adjustable relative to a ratchet wheel to incrementally rotate the ratchet wheel.

36. The method of claim 35, further comprising driving the incremental rotation of the ratchet wheel using force from a spring coupled to the pawl to drive the pawl from a reset position toward a forward position.

37. The method of claim 36, wherein the string member winds around the spindle member and thereby urges the pawl member toward the reset position.

38. A method for dispensing medicine from an infusion pump system, comprising:

rotating a motor to unwind a string member from a spindle and thereby adjust a ratchet mechanism coupled to a piston rod, wherein the adjustment of the ratchet mechanism incrementally advances the piston rod in a forward direction to force medicine from a wearable medicine dispenser device; and

rotating the motor to wind the string member around the spindle and thereby apply a tension force to reset the ratchet mechanism.

39. The method of claim 38, wherein rotating the motor to unwind the string member comprises rotating the motor one or more full rotations in a first rotational direction.

40. The method of claim 39, wherein rotating the motor to wind the string member comprises continuing to rotate the motor in the first rotational direction.

41. The method of claim 40, further comprising, in a next dispensing cycle, rotating the motor one or more full rotations in an opposite, second rotational direction to unwind the string member from the spindle.

42. The method of claim 38, wherein the spindle is arranged coaxially with a rotational shaft of the motor.

43. The method of claim 38, wherein the ratchet mechanism comprises a pawl that is adjustable relative to a ratchet wheel to incrementally rotate the ratchet wheel.

44. The method of claim 43, further comprising driving the incremental rotation of the ratchet wheel using force from a spring coupled to the pawl to drive the pawl from a reset position toward a forward position.

45. The method of claim 44, wherein the string member winds around the spindle member and thereby urges the pawl member toward the reset position.