Two chamber pumps and related methods

• US 8,986,253 B2
• Filed: 08/07/2009
• Issued: 03/24/2015
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: Tandem Diabetes Care Incorporated
• Original Assignee: Tandem Diabetes Care Incorporated
• Inventors: DiPerna, Paul M.
• Primary Examiner(s): BERTHEAUD, PETER JOHN
• Application Number:
  US12/538,018
• Publication Number:
  US 20100008795A1
• Time in Patent Office: 2,055 Days
• Field of Search: 417/53, 417/54, 417/472, 417/473, 604/131, 604/132, 604/140, 604/141
• US Class Current: 604/141
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 5/1486 the bags being substantially completely surrounded by fluid
• CPC Class Codes: A61M 5/16809 by repeated filling and emptying of an intermediate volume pressure infusion using positive displacement pumps A61M5/142
• CPC Class Codes: A61M 5/16886 for measuring fluid flow rate, i.e. flowmeters
• CPC Class Codes: F04B 43/06 Pumps having fluid drive
• CPC Class Codes: F04B 43/10 Pumps having fluid drive

Abstract

Two chamber pumps and related methods provide a platform for measuring flow rate in about real time without contacting the material being pumped. Pressure and optional temperature sensors disposed in a pressurized chamber allow for flow material delivery calculations after being calibrated or by knowing the initial volume of the flow material to be delivered.

Claims

1. A device comprising:

a pressurizable, fluid-tight, sealed first chamber, the first chamber comprising a flexible material that is expandable and collapsible depending on a pressure of a pressurized substance within the first chamber to define a variable volume of the first chamber;

a second chamber fully enclosed within the pressurized substance of the first chamber for holding a flow material;

at least one flow lumen in flow material communication with the second chamber;

at least one sensor disposed in the first chamber;

a flow controller disposed along the flow lumen; and

a microprocessor for calculating flow rate from data provided by the at least one sensor, the flow rate calculation accounting for the variable volume of the first chamber;

wherein the first chamber is configured such that when the pressurized substance having a pressure higher than the flow material in the second chamber is in the first chamber, the pressurized substance effects a change of volume of the second chamber; and

wherein the microprocessor controls the flow controller.

2. The device of claim 1, further comprising a fill port for filling the second chamber with the flow material.

3. The device of claim 1, wherein the sensor is a pressure sensor.

4. The device of claim 3, further comprising at least one temperature sensor disposed in the first chamber.

5. The device of claim 1, wherein the flow controller is a flow restrictor.

6. The device of claim 1, wherein the flow controller is a flow metering device.

7. The device of claim 1, wherein an expansion of the flexible material is a function of the pressure of the first chamber.

21. The device of claim 1, wherein the microprocessor is configured to determine the flow rate according to an equation:

8. A device comprising:

a pressurizable first chamber, the first chamber comprising a flexible material that is expandable and collapsible depending on a pressure within the first chamber;

a second chamber enclosed by the first chamber for holding a flow material;

at least one flow lumen in flow material communication with the second chamber;

at least one sensor disposed in the first chamber;

a flow controller disposed along the flow lumen; and

a microprocessor for calculating flow rate from data provided by the at least one sensor, the flow rate calculation accounting for expansion and contraction of the first chamber due to changes in pressure within the first chamber,

wherein the first chamber is configured to be filled with a pressurized substance that directly contacts an inner perimeter of the first chamber and that contacts an outer perimeter of the second chamber and that effects a change of volume of the second chamber; and

wherein the microprocessor controls the flow controller.

9. The device of claim 8, further comprising a fill port for filling the second chamber with the flow material.

10. The device of claim 8, wherein the sensor is a pressure sensor.

11. The device of claim 10, further comprising at least one temperature sensor disposed in the first chamber.

12. The device of claim 8, wherein the flow controller is a flow restrictor.

13. The device of claim 8, further comprising at least one temperature sensor wherein the microprocessor gathers data from the temperature sensor to compute a flow rate of flow material transferred through the flow lumen from the second chamber.

14. A method comprising:

providing a pump including;

(a) a pressurizable, fluid-tight, sealed first chamber, the first chamber comprising a flexible material that is expandable and collapsible depending on a pressure of a pressurized substance within the first chamber with a volume of the first chamber being predictably variable as the first chamber expands and collapses;

(b) a second chamber fully enclosed within the pressurized substance of the first chamber for holding a flow material;

(c) at least one sensor disposed in the first chamber and a microprocessor adapted to calculate flow rate of the flow material from data provided by the sensor based at least in part on the predictably variable volume of the first chamber;

(d) a flow lumen in flow material communication with the second chamber; and

(e) a flow controller; and

causing the flow material to flow from the second chamber and through the flow controller with the pressurized substance in the first chamber having a pressure greater than the flow material in the second chamber thereby changing a volume of the second chamber.

15. The method of claim 14, wherein providing the pump includes providing a pump wherein the sensor is a pressure sensor.

16. The method of claim 15, wherein providing the pump comprises providing a pump wherein at least one temperature sensor is disposed in the first chamber.

17. The method of claim 15, wherein providing the pump includes providing a pump wherein the flow controller is a flow restrictor.

18. The method of claim 14, wherein providing the pump includes providing a pump wherein the flow controller is a flow metering device.

19. The method of claim 15, further comprising computing flow rate from the data provided by the pressure sensor with the microprocessor and controlling the flow controller with the microprocessor.

20. The method of claim 14, further comprising pressurizing the first chamber prior to filling the second chamber with the flow material.