Dispensing Fluid from an Infusion Pump System

• US 20070179444A1
• Filed: 02/22/2007
• Published: 08/02/2007
• Est. Priority Date: 09/26/2005
• Status: Active Grant

• Current Assignee: Insulet Corporation
• Original Assignee: M2 Medical A/S
• Inventors: Wenger, Mitchell, Kirschen, Todd, Causey, James, Friedman, Steven, Colton, Joshua, Christensen, Keld
• Granted Patent: US 8,057,436 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 a medical infusion pump system include a pump device having a cap device that mates with a pump housing to retain a medicine cartridge therein. In addition to retaining the medicine cartridge in the pump housing, the cap device may perform a number of preparatory functions or safety functions. In addition or in the alternative, some embodiments of the pump device may include a drive system that advances a piston rod to dispense medicine to the patient in a safe and energy efficient manner.

Claims

1. An infusion pump device, comprising:

a pump housing that defines a space to receive a medicine;

a drive system to dispense a medicine from the pump housing when the medicine is received in the space, the drive system comprising;

a ratchet mechanism that advances a piston rod during a drive step to dispense the medicine when the medicine is received in the space; and

an electrically powered actuator that decouples from the ratchet mechanism during the drive step.

2. The infusion pump device of claim 1, wherein the drive system further comprises a spring device that provides a drive force to the ratchet mechanism during the drive step to advance the ratchet mechanism in a forward direction.

3. The infusion pump device of claim 2, wherein the electrically powered actuator is coupled to the ratchet mechanism during a reset cycle to provide a reset force to the ratchet mechanism.

4. The infusion pump device of claim 3, wherein the electrically powered actuator expends a short burst of electrical energy to reset the ratchet mechanism and contributes no force upon the ratchet mechanism when the spring device advances the ratchet mechanism in the forward direction.

5. The infusion pump device of claim 1, wherein the electrically powered actuator comprises a bi-directional actuator.

6. The infusion pump device of claim 5, wherein the electrically powered actuator comprises a reversible rotational motor.

7. The infusion pump device of claim 1, wherein the drive system further comprises a pusher arm coupled to the electrically powered actuator, the pusher arm shifting from abutment with the ratchet mechanism to separation from the ratchet mechanism when the electrically powered actuator decouples from the ratchet mechanism.

8. The infusion pump device of claim 7, wherein the pusher arm is advanced and retracted by the electrically powered actuator, and at least a portion of the pusher arm movement is directed by a guide slot.

9. The infusion pump device of claim 7, wherein the pusher arm is coupled to the electrically powered actuator via one or more gears.

10. The infusion pump device of claim 1, wherein the space in the pump housing is defined to receive a medicine cartridge that contains the medicine.

11. The infusion pump device of claim 10, wherein the piston rod includes a plunger engagement device that attaches to a plunger of the medicine cartridge when the medicine cartridge is received by the pump housing.

12. The infusion pump device of claim 11, further comprising a cap device that engages the pump housing to retain the medicine cartridge therein when the medicine cartridge is received by the pump housing, wherein when the cap device engages the pump housing, the cap device acts upon the medicine cartridge to urge the plunger into attachment with the plunger engagement device of the piston rod.

13. The infusion device of claim 12, wherein the plunger engagement device comprises one or more penetration members that pierce into a first side of the plunger during attachment of the plunger and the plunger engagement device.

14. An infusion pump device, comprising:

a pump housing that defines a space to receive a medicine;

a drive system to dispense a medicine from the pump housing when the medicine is received in the space, the drive system comprising;

a drive wheel that rotates to advance a piston rod toward the medicine to dispense the medicine when the medicine is received in the space;

a ratchet wheel that is incrementally rotated in a forward direction to rotate the drive wheel and thereby advance the piston rod;

a movable pawl that engages the ratchet wheel, the movable pawl being adjustable from a reset position to a forward position so as to incrementally rotate the ratchet wheel in the forward direction a spring device that urges the movable pawl to adjust from the reset position to the forward position; and

an actuator assembly that acts upon the movable pawl to force the movable pawl to the reset position and that reverses to separate from the movable pawl when the spring device adjusts the movable pawl from the reset position to the forward position.

15. The infusion pump device of claim 14, wherein the actuator assembly comprises an electrically powered motor and a pusher arm, the pusher arm being adjustable from abutment with the movable pawl to separation from the movable pawl.

16. The infusion pump device of claim 15, wherein the pusher arm is advanced and retracted by the electrically powered actuator, and at least a portion of the pusher arm movement is directed by a guide slot.

17. The infusion pump device of claim 15, wherein actuator assembly further comprises one or more gears that couple the pusher arm the electrically powered actuator.

18. The infusion pump device of claim 15, wherein the electrically powered actuator comprises a bi-directional actuator.

19. The infusion pump device of claim 18, wherein the electrically powered actuator comprises a reversible rotational motor.

20. The infusion pump device of claim 14, wherein the actuator assembly comprises an electrically powered that expends a short burst of electrical energy to force the movable pawl to the reset position and that contributes no force upon the movable pawl when the spring device adjusts the movable pawl from the reset position to the forward position.

21. The infusion pump device of claim 14, wherein the space in the pump housing is defined to receive a medicine cartridge that contains the medicine.

22. The infusion pump device of claim 21, wherein the piston rod includes a plunger engagement device that attaches to a plunger of the medicine cartridge when the medicine cartridge is received by the pump housing.

23. The infusion pump device of claim 22, further comprising a cap device that engages the pump housing to retain the medicine cartridge therein when the medicine cartridge is received by the pump housing, wherein when the cap device engages the pump housing, the cap device acts upon the medicine cartridge to urge the plunger into attachment with the plunger engagement device of the piston rod.

24. The infusion device of claim 23, wherein the plunger engagement device comprises one or more penetration members that pierce into a first side of the plunger during attachment of the plunger and the plunger engagement device.

25. A method of dispensing medicine from an infusion pump device, comprising:

resetting a ratchet mechanism in a drive system of an infusion pump device by activating an electrically powered actuator to provide a reset force to a ratchet mechanism;

driving the ratchet mechanism in a forward direction to advance a piston rod during a drive step so as to dispense a medicine from the infusion pump device,

wherein the electrically powered actuator is decoupled from the ratchet mechanism during the drive step.

26. The method of claim 25, wherein the ratchet mechanism is driven in the forward direction by a spring device that provides a drive force to the ratchet mechanism.

27. The method of claim 26, wherein the electrically powered actuator expends a short burst of electrical energy to reset the ratchet mechanism and contributes no force to act upon the ratchet mechanism when the spring device advances the ratchet mechanism in the forward direction.

28. The method of claim 25, wherein the electrically powered actuator provides the reset force via a pusher arm that is coupled to the electrically powered actuator, the method further comprising shifting the pusher arm from abutment with the ratchet mechanism to separation from the ratchet mechanism so as to decouple the electrically powered actuator from the ratchet mechanism.

29. The method of claim 28, wherein the pusher arm is coupled to the electrically powered actuator via one or more gears.

30. The method of claim 25, wherein the electrically powered actuator comprises a reversible rotational motor.