INFUSION PUMP WITH A CAPACITIVE DISPLACEMENT POSITION SENSOR

• US 20080152507A1
• Filed: 12/21/2006
• Published: 06/26/2008
• Est. Priority Date: 12/21/2006
• Status: Abandoned Application

• Current Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Bohm, Sebastian
• Application Number:
  US11/614,364
• Publication Number:
  US 20080152507A1
• Time in Patent Office: Days
• US Class Current: 417/44.1
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3389 Continuous level detection A61M2205/3393 takes precedence
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14526 the piston being actuated by fluid pressure
• CPC Class Codes: A61M 5/14566 with a replaceable reservoir for receiving a piston rod of the pump
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: F04B 17/00 Pumps characterised by combination with, or adaptation to, specific driving engines or motors
• CPC Class Codes: F04B 2201/0201 Position of the piston
• CPC Class Codes: F04B 9/107 rectilinear movement of the pumping member in the working direction being obtained by a single-acting liquid motor, e.g. actuated in the other direction by gravity or a spring

Abstract

Various methods and devices are provided for an electrokinetic infusion pump. In one embodiment of the invention, the infusion pump includes an infusion pump module, which can be configured to dispense an insulin containing infusion liquid, and an electrokinetic engine. The infusion pump module includes a capacitive displacement position sensor configured for sensing a dispensing state of the infusion pump module. The infusion pump module can include an infusion module housing and the electrokinetic engine can include a moveable partition. The capacitive displacement sensor includes a first capacitive plate disposed on the moveable partition and a second capacitive plate disposed on the infusion module housing. The capacitive displacement sensor is configured for measuring capacitance between the first capacitive plate and the second capacitive plate and can send a feedback signal to a closed loop controller that is indicative of the capacitance between the first and second capacitive plates.

Claims

1. An electrokinetic infusion pump comprising:

an infusion pump module; and

an electrokinetic engine,

wherein the infusion pump module includes a capacitive displacement position sensor configured for sensing a dispensing state of the infusion pump module.

2. The electrokinetic infusion pump of claim 1, wherein:

the infusion pump module includes an infusion module housing;

the electrokinetic engine includes a moveable partition; and

the capacitive displacement sensor includes a first capacitive plate disposed on the moveable partition and a second capacitive plate disposed on the infusion module housing.

3. The electrokinetic infusion pump of claim 2, wherein the first capacitive plate and the second capacitive plate each have a width of approximately 10 mm and a length of approximately 20 mm.

4. The electrokinetic infusion pump of claim 3, wherein a gap between the first capacitive plate and the second capacitive plate has a dimension in the range of approximately 10-1000 micrometer.

5. The electrokinetic infusion pump of claim 2, wherein the capacitive displacement sensor is configured for measuring capacitance between the first capacitive plate and the second capacitive plate.

6. The electrokinetic infusion pump of claim 1, wherein the electrokinetic engine includes a moveable partition and the infusion pump includes an infusion housing, and wherein the capacitive displacement sensor is a dual capacitive displacement sensor that includes:

a first capacitive plate and a second capacitive plate disposed on the moveable partition; and

a third capacitive plate and a fourth capacitive plate disposed on the infusion housing;

wherein the first capacitive plate, the second capacitive plate, the third capacitive plate and the fourth capacitive plate are in operative electrical contact and wherein an overlap between the second and fourth capacitive plate is constant and an overlap between the first capacitive plate and the third capacitive plate is dependent on a position of the moveable partition.

7. The electrokinetic infusion pump of claim 1, wherein the capacitive displacement sensor is configured to send a feedback signal to a closed loop controller, the feedback signal indicative of the capacitance between the first and second capacitive plates.

8. The electrokinetic infusion pump of claim 1, wherein the infusion pump is configured to dispense an insulin containing infusion liquid.

9. An infusion pump system, comprising:

an infusion pump that includes;

a capacitive displacement position sensor; and

a closed loop controller,

wherein the infusion pump and closed loop controller are in operative communication and configured such that the closed loop controller can determine and control a dispensing state of the infusion pump based on a feedback signal received from the capacitive displacement position sensor.

10. The system of claim 9, wherein the infusion pump is an electrokinetic pump.

11. The system of claim 10, wherein the electrokinetic infusion pump further includes

an infusion pump module;

and

an electrokinetic engine,

and wherein the capacitive displacement sensor is configured for sensing a dispensing state of the infusion pump module.

12. The system of claim 11, wherein:

the infusion pump module includes an infusion module housing;

the electrokinetic engine includes a moveable partition; and

the capacitive displacement sensor includes a first capacitive plate disposed on the moveable partition and a second capacitive plate disposed on the infusion module housing.

13. The system of claim 12, wherein the capacitive displacement sensor is configured for sensing a dispensing state by measuring capacitance between the first capacitive plate and the second capacitive plate.

14. The system of claim 13, wherein the first capacitive plate and the second capacitive plate each have a width of approximately 10 mm and a length of approximately 20 mm.

15. The system of claim 14, wherein a gap between the first capacitive plate and the second capacitive plate has a dimension in the range of approximately 10-1000 micrometer.

16. The system of claim 11, wherein the electrokinetic engine includes a moveable partition and wherein the capacitive displacement sensor is a dual capacitive displacement sensor that includes:

a first capacitive plate;

a second capacitive plate;

a third capacitive plate; and

a fourth capacitive plate,

and wherein the first capacitive plate, the second capacitive plate, the third capacitive plate and the fourth capacitive plate are in operative electrical contact and wherein an overlap between the second and fourth capacitive plate is constant and an overlap between the first capacitive plate and the third capacitive plate is dependent on a position of the moveable partition.

17. The system of claim 11, wherein the electrokinetic engine includes an electrokinetic supply reservoir that is at least partially collapsible.

18. The system of claim 9, wherein the capacitive displacement sensor is configured to send the feedback signal to the closed loop controller.

19. The system of claim 9, wherein the infusion pump is configured to dispense an insulin-containing infusion liquid.

20. A method for the closed loop control of an infusion pump, comprising:

sensing a dispensing state of an infusion pump with a capacitive displacement position sensor;

signaling the sensed dispensing state of the infusion pump to a closed loop controller via a feedback signal;

determining, with the closed loop controller, the dispensing state of the infusion pump based feedback signal; and

controlling the dispensing state of the infusion pump with the closed loop controller by sending command signals from the closed loop controller to an engine driving the infusion pump.