Pumping cassette

• US 8,926,294 B2
• Filed: 11/26/2012
• Issued: 01/06/2015
• Est. Priority Date: 02/27/2007
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Demers, Jason A., Wilt, Michael J., Grant, Kevin L., Dale, James D., Tracey, Brian D.
• Primary Examiner(s): LETTMAN, BRYAN MATTHEW
• Application Number:
  US13/684,995
• Publication Number:
  US 20130177457A1
• Time in Patent Office: 771 Days
• Field of Search: 417/323, 417/379, 417/392, 417/394, 417/395, 417/413.1, 417/439, 417/440, 417/442, 417/479, 417/521, 210/645, 210/646, 604/6.11
• US Class Current: 417/395
• CPC Class Codes: A61M 1/154 with sensing means or components thereof
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/1561 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 1/15625 the reservoirs acting as balance chambers
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1639 linked by membranes
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/1664 with temperature control
• CPC Class Codes: A61M 1/1666 by dissolving solids
• CPC Class Codes: A61M 1/287 Dialysates therefor
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/128 with incorporated valves
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 PH measuring means
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/268 the displacement member being flexible, e.g. membranes, diaphragms or bladders
• CPC Class Codes: A61M 60/37 Haemodialysis, haemofiltration or diafiltration
• CPC Class Codes: A61M 60/427 : the force acting on the blood contacting member being hydraulic or pneumatic
• CPC Class Codes: A61M 60/43 : using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/837 : Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/847 : arranged in a cassette
• CPC Class Codes: A61M 60/849 : Disposable parts
• CPC Class Codes: A61M 60/851 : Valves
• CPC Class Codes: A61M 60/892 : Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 : Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F04B 13/02 : of two or more fluids at the same time
• CPC Class Codes: F04B 23/06 : the pumps being all of reciprocating positive-displacement type
• CPC Class Codes: F04B 41/06 : Combinations of two or more pumps
• CPC Class Codes: F04B 43/00 : Machines, pumps, or pumping installations having flexible working members pumps or pumping installations specially adapted for elastic fluids F04B45/00
• CPC Class Codes: F04B 43/026 : each plate-like pumping flexible member working in its own pumping chamber
• CPC Class Codes: F04B 43/06 : Pumps having fluid drive
• CPC Class Codes: F04B 43/0736 : with two or more pumping chambers in parallel
• CPC Class Codes: F04B 45/02 : having bellows
• CPC Class Codes: F04B 45/0536 : the actuating fluid being controlled by one or more valves
• CPC Class Codes: F04B 49/02 : Stopping, starting, unloading or idling control
• CPC Class Codes: F04B 49/22 : by means of valves F04B49/03 takes precedence
• CPC Class Codes: F04B 53/06 : Venting
• 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: F04B 7/02 : the valving being fluid-actuated
• CPC Class Codes: F04B 9/109 : having plural pumping chambers
• CPC Class Codes: F17D 3/00 : Arrangements for supervising or controlling working operations
• CPC Class Codes: Y02A 90/10 : Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
• CPC Class Codes: Y10T 137/0324 : With control of flow by a condition or characteristic of a fluid
• CPC Class Codes: Y10T 137/0379 : By fluid pressure
• CPC Class Codes: Y10T 137/2521 : Flow comparison or differential response
• CPC Class Codes: Y10T 137/85978 : With pump
• CPC Class Codes: Y10T 137/86139 : Serial

Abstract

A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.

Claims

1. A pumping cassette comprising:

a housing comprising a first fluid line including a first fluid inlet and a first fluid outlet for a first liquid flowpath configured to contain a first liquid, and a second fluid line including a second fluid inlet and a second fluid outlet for a second liquid flowpath configured to contain a second liquid;

a first and a second balancing pods within said housing and in fluid communication with said fluid lines, each one of said first and second balancing pods defining a cavity in which a flexible membrane is disposed, said flexible membrane dividing the cavity between a first chamber and a second chamber, the first chamber in fluid communication with the first fluid line, and the second chamber in fluid communication with the second fluid line, wherein said second chamber is configured to receive a first volume of the second liquid from the second fluid line by expelling a substantially equal volume of the first liquid from the first chamber into the first fluid line; and

a first and a second reciprocating positive displacement membrane pumps within said housing, each one of said first and second membrane pumps comprising an actuation chamber separated from a pumping chamber by a flexible membrane, wherein each one of said first and second membrane pumps is in fluid communication with the second fluid line, wherein the first membrane pump is configured to deliver in a pump stroke a volume of the second liquid into the second chamber of the first balancing pod, and wherein the second membrane pump is configured to deliver in a pump stroke a volume of the second liquid into the second chamber of the second balancing pod.

2. The cassette of claim 1, further comprising a metering pump within said housing and fluidly connected to said first or second fluid lines, wherein said metering pump is configured to pump a volume of the first or the second liquid such that pumped liquid bypasses the first and the second balancing pods.

3. The cassette of claim 2, wherein said first and second reciprocating positive displacement membrane pumps and said metering pump are pneumatically actuated membrane pumps.

4. The cassette of claim 1, wherein each one of said first and second reciprocating positive displacement pumps comprises:

a curved rigid chamber wall; and

a flexible membrane attached to an interior surface of the rigid chamber wall, wherein said flexible membrane separates a cavity defined by the curved rigid chamber wall into a pumping chamber and an actuation chamber.

5. The cassette of claim 1, wherein said cassette housing comprises a top plate, a mid-plate, and a bottom plate.

6. The cassette of claim 1 further comprising at least a first fluid valve in the first fluid line between the first fluid inlet and the first or the second balancing pod, and at least a second fluid valve in the second fluid line between the second fluid outlet and the first or the second balancing pod.

7. The cassette of claim 6, wherein said at least first and second fluid valves are membrane valves, each comprising a valve housing in which a membrane is disposed, the membrane separating the valve housing into a valving chamber in fluid communication with the first or the second fluid lines, and an actuation chamber for connection to a source of positive or negative pressure.

8. The cassette of claim 7, wherein said valving chamber comprises a raised valve seat configured to contact the valve membrane.

9. The cassette of claim 7, wherein said valving chamber comprises a valve seat configured to contact the valve membrane, said valve seat having a substantially smooth surface.

10. The cassette of claim 6, wherein said at least first fluid valve is a check valve.