Rotary axial peristaltic pumps and related methods

• US 20070048161A1
• Filed: 08/26/2005
• Published: 03/01/2007
• Est. Priority Date: 08/26/2005
• Status: Active Grant

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Inventors: Moubayed, Ahmad-Maher
• Granted Patent: US 7,556,481 B2
• Time in Patent Office: Days
• US Class Current: 417/477.100
• CPC Class Codes: F04B 43/082 the tubular flexible member being pressed against a wall by a number of elements, each having an alternating movement in a direction perpendicular to the axes of the tubular member and each having its own driving mechanism
• CPC Class Codes: F04B 43/12 having peristaltic action

Abstract

Rotary axial peristaltic pumps, related methods and components. The rotary axial peristaltic pump generally comprises a platen having a platen surface, a tube positioned adjacent to the platen surface, cam that rotates about a rotational axis and has a cam surface that is spaced apart from the platen surface and a plurality of tube compressing fingers. The fingers move axially back and forth in sequence to sequentially compress segments or regions of the tube against the platen surface, thereby causing peristaltic movement of fluid through the tube. The fingers move back and forth on axes that are substantially parallel to the axis about which the cam rotates.

Claims

1. A peristaltic pump device comprising:

a platen having a platen surface;

a tube positioned adjacent to the platen surface;

a cam that rotates about a rotational axis, said cam having a cam surface that is spaced apart from the platen surface; and

a plurality of fingers, each finger having a longitudinal axis that is substantially parallel to the rotational axis of the cam, said fingers being in engagement with the cam surface such that, as the cam rotates about the rotational axis, the fingers will move axially back and forth, sequentially compressing the tube against the platen surface and thereby causing peristaltic movement of fluid through the tube.

2. A device according to claim 1 wherein the platen surface is substantially planar.

3. A device according to claim 1 wherein the cam surface includes a plurality of lobes.

4. A device according to claim 1 wherein each lobe of the cam comprises a wave in the cam surface, each such wave having a peak, the peak of each wave being closer to the platen surface than the remainder of the platen surface.

5. A device according to claim 1 further comprising a tube holder that holds the tubing adjacent to the platen surface.

6. A device according to claim 5 wherein the tube holder comprises a plurality of tube-receiving notches within which the tube is received.

7. A device according to claim 5 wherein the platen surface is substantially flat and the tube holder holds the tube in a generally shape adjacent to the substantially flat platen surface.

8. A device according to claim 1 further comprising a door that may be opened and closed.

9. A device according to claim 1 wherein the platen surface is located on one side of the door.

10. A device according to claim 9 further comprising a tube holder that holds the tubing adjacent to the platen surface.

11. A device according to claim 10 wherein the tube holder comprises a plurality of tube-receiving notches within which the tube is received.

12. A device according to claim 11 wherein the platen surface is substantially flat and the tube holder holds the tube in a generally shape adjacent to the substantially flat platen surface.

13. A device according to claim 8 wherein the door may be opened to gain access to the tube.

14. A device according to claim 13 wherein the tube may be removed and replaced by another tube.

15. A device according to claim 1 further comprising a tube cassette which includes said tube.

16. A device according to claim 15 wherein the tube cassette may be removed and replaced by another tube cassette.

17. A device according to claim 15 wherein the tube cassette comprises a substantially rigid structure that holds the tube in a desired configuration.

18. A device according to claim 17 wherein the cassette structure holds the tube in a substantially accurate configuration.

19. A device according to claim 13 wherein the tube is mounted on or in a cassette and the door may be opened to gain access to allow removal of the cassette having the tube thereon or therein and replacement thereof with another cassette having another tube thereon or therein.

20. A device according to claim 19 wherein at least one alignment surface is formed in the door, said alignment surface being configured to register with the cassette when the door is closed, thereby holding the cassette in a desired alignment.

21. A device according to claim 20 wherein the platen surface is on an inner surface of the door and said at least one indentation is formed in said platen surface such that the tube will be substantially juxtaposed to the platen surface when the door is closed.

23. A device according to claim 21 wherein the cassette comprises a plurality of strut members through which the tube extends and wherein a plurality of strut member receiving indentations are received in the platen surface such that, when the door is closed, the strut members will be received in the strut member receiving indentations and the tube will be substantially juxtaposed with the platen surface.

24. A device according to claim 1 wherein at least one of the fingers is associated with an apparatus for retracting that finger away from the platen surface.

25. A device according to claim 24 wherein the apparatus for retracting that finger comprises a spring that urges the finger away from the platen surface.

26. A device according to claim 24 wherein substantially all of the fingers are associated with apparatus for retracting those fingers away from the platen surface.

27. A device according to claim 24 wherein the at least one finger associated with an apparatus for retracting that finger is not coupled to the cam in a way that would cause the cam to pull that finger away from the platen surface during a portion of the pumping cycle.

28. A device according to claim 24 wherein the apparatus for retracting that finger substantially maintains that finger in contact with the cam surface.

29. A device according to claim 24 wherein the apparatus for retracting that finger comprises a spring.

30. A device according to claim 1 wherein the fingers comprise finger assemblies, each finger assembly comprising i) a body having first portion at one end and a second portion at the other end, ii) a cam-contacting surface located on the first portion of the body and iii) a tube-compressing surface located on the second portion of the body.

31. A device according to claim 30 wherein said finger assembly further comprises a spring for retracting the tube-compressing member during a portion of the pumping cycle.

32. A device according to claim 1 wherein the cam surface is located on a peripheral region of the cam.

33. A device according to claim 1 wherein the cam surface includes a substantially flat, concave or convex race surface.

34. A device according to claim 33 wherein the race comprises a groove having a substantially accurate wall.

35. A device according to claim 33 wherein the race comprises a groove having a substantially V shaped wall.

36. A device according to claim 33 wherein the race comprises a groove having a substantially tapered wall.

37. A device according to claim 33 wherein the race comprises a raised area on the cam.

38. A device according to claim 33 wherein the fingers have rollers that ride on or in the race.

39. A device according to claim 34 wherein the fingers have substantially spherical rollers that ride against the substantially accurate wall.

40. A device according to claim 35 wherein the fingers have rollers that ride against locations on opposing sides of the substantially V shaped wall.

41. A device according to claim 36 wherein the fingers have rollers that ride against the substantially tapered wall.

42. A device according to claim 37 wherein the fingers have rollers that are configured to ride on the raised area.

43. A device according to claim 33 wherein an axial plane is projectable through the race, said axial plane being substantially perpendicular to the axis of rotation about which the cam rotates.

44. A device according to claim 1 wherein each at least one of the fingers includes an occlusion element that compresses the tube sufficiently to substantially occlude the tube lumen during a portion of the pumping cycle.

45. A device according to claim 44 wherein the finger has a tube compressing surface of a first width and the tube occluding element protrudes beyond the tube compressing surface, said tube occluding element having a second width that is less than said first width.

46. A device according to claim 44 wherein each finger has a maximum point of travel where the occlusion element is as close as it comes to the platen surface, and wherein each occlusion element is spring biased so as to exert a controlled amount of compressive force on the tube when that finger is at or within a predetermined distance from its maximum point of travel.

47. A device according to claim 44 wherein a transverse slot is formed in the pump finger and the occlusion element is slidably disposed within that transverse slot.

48. A device according to claim 47 wherein the pump finger further comprises a spring that urges the occlusion element to an extended position.

49. A device according to claim 1 further comprising a controller for controlling the operation of the device.

50. A device according to claim 15 wherein the tube cassette incorporates an identifying feature that is identifiable by the pumping device.

51. A device according to claim 49 wherein the tube is mounted in or on a tube cassette, wherein the tube cassette incorporates an identifying feature that is identifiable by the controller and wherein the controller is programmed to deter operation of the device with cassettes that do not incorporate an acceptable identifying feature.

52-80. -80. (canceled)