Rotary axial peristaltic pumps and related methods

• US 20080101968A1
• Filed: 05/19/2006
• Published: 05/01/2008
• 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 8,308,456 B2
• Time in Patent Office: Days
• US Class Current: 417/474
• 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

1-57. -57. (canceled)

58. A pump finger/cam assembly for use in a finger-type peristaltic pump wherein a plurality of fingers sequentially compress and decompress a pump tube against a platen thereby causing peristaltic movement of fluid through the pump tube, said pump finger/cam assembly comprising:

a cam having a concaved race formed therein, said cam rotating about an axis of cam rotation, said cam;

a plurality of fingers, each finger having a tube-compressing surface at one end and a roller at the other end, said roller being rotatable about an axis of roller rotation;

said roller riding rotatably within the race of the cam such that the axis of roller rotation is substantially perpendicular to the axis of cam rotation.

59. An assembly according to claim 58 wherein the race has a substantially accurate wall and the roller is substantially spherical.

60. An assembly according to claim 58 wherein the race has a substantially V shaped wall and the roller contacts opposite sides of the substantially V shaped wall.

61. An assembly according to claim 58 wherein the race has a substantially tapered wall and the roller contacts the substantially tapered wall.

62. An assembly according to claim 58 wherein the race has a raised surface and the roller is configured to ride on said raised surface.

63. An assembly according to claim 58 wherein the race has a raised surface and the roller is configured to ride on said raised surface.

64. An assembly according to claim 58 wherein the cam surface includes a plurality of lobes.

65. An assembly according to claim 64 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.

66. An assembly according to claim 58 further comprising a retraction apparatus for retracting the tube-compressing surface of the finger away from the tube after the finger has compressed the tube.

67. An assembly according to claim 66 wherein the retraction apparatus comprises a spring.

70. An assembly according to claim 58 wherein the cam surface is located on a peripheral region of the cam.

71. An assembly according to claim 58 wherein the finger comprises a tube occlusion element that protrudes beyond the tube compressing surface, said occlusion element being configured to substantially occlude the lumen of the tube during a portion of the pumping cycle.

72. An assembly according to claim 71 wherein the tube-contacting surface has a first width and the occlusion element has a second width that is narrower than the first width.

73. An assembly according to claim 71 wherein each finger has a maximum point of travel where the tube occlusion element is as close as it comes to the platen, and wherein each tube 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 of its maximum point of travel.

74. An assembly according to claim 73 wherein a transverse slot is formed in the finger and the tube occlusion element is slidably disposed within that transverse slot.

75. An assembly according to claim 74 further comprising a spring that urges the tube occlusion element to an extended position.

67-1. An assembly according to claim 65 wherein the retraction apparatus biases the finger in the direction of the cam.

69. An assembly according to claim 68 wherein the retraction apparatus biases the finger such that the roller remains in contact with the race at all points of rotation of the cam.

76-80. -80. (canceled)