PUMP CHAMBER CONFIGURED TO CONTAIN A RESIDUAL FLUID VOLUME FOR INHIBITING THE PUMPING OF A GAS

• US 20130343936A1
• Filed: 08/22/2013
• Published: 12/26/2013
• Est. Priority Date: 07/20/1999
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Gray, Larry B.
• Granted Patent: US 9,494,150 B2
• Time in Patent Office: Days
• US Class Current: 417/437
• CPC Class Codes: A61M 1/1649 with pulsatile dialysis fluid flow
• CPC Class Codes: A61M 1/267 used for pumping
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362261 at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil
• CPC Class Codes: A61M 1/362264 the filter being a blood filter
• CPC Class Codes: A61M 1/362265 Details of valves
• CPC Class Codes: A61M 1/362266 Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/367 Circuit parts not covered by the preceding subgroups of group A61M1/3621
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2209/02 Equipment for testing the apparatus
• CPC Class Codes: A61M 39/228 with a tubular diaphragm constrictable by radial fluid force
• CPC Class Codes: A61M 5/14 Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: A61M 5/14593 the diaphragm being actuated by fluid pressure
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: F04B 43/067 the fluid being actuated directly by a piston
• CPC Class Codes: F04B 45/00 Pumps or pumping installations having flexible working members and specially adapted for elastic fluids
• CPC Class Codes: F04B 45/02 having bellows
• CPC Class Codes: F04B 49/065 and making use of computers
• CPC Class Codes: F04B 49/12 : by varying the length of stroke of the working members
• CPC Class Codes: F04B 53/10 : Valves; Arrangement of valves
• CPC Class Codes: F04B 53/16 : Casings; Cylinders; Cylinder liners or heads; Fluid connections
• CPC Class Codes: G01M 3/26 : by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
• CPC Class Codes: G01M 3/32 : for containers, e.g. radiators
• CPC Class Codes: G05D 16/20 : characterised by the use of electric means

Abstract

The present invention involves, in some embodiments, mechanisms and methods of occluding collapsible tubing with an occluder to prevent fluid flow therethrough. In some embodiments, a tube occluding mechanism is disclosed that includes a bendable occluding member for creating a force that can be applied to a collapsible tube to occlude the tube. In some embodiments, the collapsible tube can be an inlet/outlet tube on a removable pumping cartridge that is coupled to a reusable pump drive component when the system is in operation. In such embodiments, the occluding mechanism can be attached to the reusable component and can be used to block fluid flow to and from the pumping cartridge. In some embodiments, the occluding member can comprises a spring plate which can create a force to occlude tubing when in a relaxed, unbent configuration, and which can be bent to unocclude the tubing. In some preferred embodiments, in a default configuration of the tube occluder mechanism (when no external force is applied to the occluding member) the tubes are occluded, so that the tube occluder mechanism provides a fail-safe configuration preventing fluid flow to and from a pumping cartridge to which the tubes can be connected.

Claims

1. A pump chamber for pumping fluid, comprising:

a movable membrane positioned opposite a rigid inner wall to form the pump chamber, the membrane configured and positioned within the pump chamber to move fluid out of the pump chamber through an outlet of the pump chamber as the membrane moves toward the inner wall from a first position to a second, fully extended position, wherein when in the second position, at least a portion of the membrane is prevented from contacting the inner wall so that a residual volume able to contain fluid remains within the pump chamber.

2. The pump chamber of claim 1, wherein the residual volume of the fluid within the pump chamber prevents all of the fluid within the pump chamber from being expelled through the outlet.

3. The pump chamber of claim 2, wherein the inner wall of the pump chamber comprises raised features that prevent the membrane from contacting at least a portion of the inner wall.

4. The pump chamber of claim 3, wherein the residual volume comprises spacing among the raised features.

5. The pump chamber of claim 1, wherein the outlet is located at or near the bottom of the pump chamber when the pump chamber is in an operational position.

6. The pump chamber of claim 2, wherein the fluid in the residual volume comprises a mixture of liquid and gas.

7. The pump chamber of claim 1, wherein the movable membrane is a flexible membrane, the opposing rigid inner wall is generally concave, and the periphery of the membrane is sealed against a circumference of the opposing rigid inner wall.

8. The pump chamber of claim 1, wherein the pump chamber further comprises an inlet through which fluid can enter as the membrane moves away from the inner wall.

9. The pump chamber of claim 8, wherein the inlet is spaced apart from the outlet and configured in a manner that the outlet is below the inlet when the pump chamber is in an operational position.

10. A pump chamber for pumping fluid, comprising:

a movable membrane positioned opposite a rigid inner wall, the membrane configured and positioned within the pump chamber to move fluid out of the pump chamber through an outlet of the pump chamber as the membrane moves toward the inner wall from a first position to a second, fully extended position, wherein when the membrane is in the second, fully extended position, the membrane is brought into solid contact with surfaces within the interior of the pump chamber but is prevented from contacting at least a portion of the inner wall, leaving a residual volume able to contain fluid within the chamber.

11. The pump chamber of claim 10, wherein the residual volume of the fluid within the pump chamber prevents all of the fluid within the chamber from being expelled through the outlet.

12. The pump chamber of claim 11, wherein the inner wall of the chamber comprises raised features that prevent the membrane from contacting at least a portion of the inner wall.

13. The pump chamber of claim 12, wherein the residual volume comprises spacing among the raised features.

14. The pump chamber of claim 10, wherein the outlet is located at or near the bottom of the pump chamber when the pump chamber is in an operational position.

15. The pump chamber of claim 11, wherein the fluid in the residual volume comprises a mixture of liquid and gas.

16. The pump chamber of claim 10, wherein the movable membrane is a flexible membrane, the opposing rigid inner wall is generally concave, and the periphery of the membrane is sealed against a circumference of the opposing rigid inner wall.

17. The pump chamber of claim 10, wherein the pump chamber further comprises an inlet through which fluid can enter as the membrane moves away from the inner wall.

18. The pump chamber of claim 17, wherein the inlet is spaced apart from the outlet and configured in a manner that the outlet is below the inlet when the pump chamber is in an operational position.