Flexible tube positive displacement pump

• US 6,685,450 B2
• Filed: 09/20/2001
• Issued: 02/03/2004
• Est. Priority Date: 09/22/2000
• Status: Expired due to Term

• Current Assignee: Avent Incorporated (Avanos Medical, Inc.)
• Original Assignee: Sorenson Development, Incorporated
• Inventors: Bandis, Steven, Haight, LeVoy G.
• Primary Examiner(s): Paik, Sang Y.
• Assistant Examiner(s): FASTOVSKY, LEONID M
• Application Number:
  US09/957,341
• Publication Number:
  US 20020071776A1
• Time in Patent Office: 866 Days
• Field of Search: 417/477.6, 417/477.3, 417/477.12, 417/63, 417/476, 417/319, 417/360, 210/90, 607/67, 607/131
• US Class Current: 417/477.6
• CPC Class Codes: F04B 43/1253 by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing
• CPC Class Codes: F04B 43/1284 Means for pushing the backing-plate against the tubular flexible member

Abstract

The pressure rollers of a peristaltic tube positive displacement pump are incorporated as an element of a reduction system connecting a drive shaft to the rollers.

Claims

1. In a peristaltic pump system in which rotating pressure elements are driven by a reduction system and are structured and arranged to revolve through a chamber in contact with a flexible tube, the improvement comprising a reaction surface, positioned opposite said rotating pressure elements, said flexible tube being positioned intermediate said rotating pressure elements and said reaction surface, said flexible tube being compressed by said rotating pressure elements and said reaction surface, each of said pressure elements having a respective follower gear secured thereto, each said follower gear being intercooperated with a drive gear and further being incorporated into said reduction system.

2. In a peristaltic pump system in which rotating pressure rollers are driven by a gear reduction system and are structured and arranged to revolve through a chamber with the outer surfaces of said rollers constituting pressure surfaces in contact with a flexible tube, whereby to cause positive displacement pumping action through said tube, the improvement comprising a reaction surface, positioned opposite said rotating pressure elements, said flexible tube being positioned intermediate said rotating pressure elements and said reaction surface, said flexible tube being compressed by said rotating pressure rollers and said reaction surface each of said pressure rollers having a respective follower gear secured thereto, each said follower gear being intercooperated with a drive gear and further being incorporated into said gear reduction system.

3. An improvement according to claim 2, wherein said follower gears are dimensioned relative to said drive gear to produce a reduction in rotational velocity of said rollers relative to said drive gear said follower gears being arranged to receive rotational force from said drive gear which receives power through a driven shaft element.

4. An improvement according to claim 2, wherein said pump system includes

a first subassembly comprising said driven shaft element;

a second subassembly comprising said pressure rollers; and

a coupling mechanism associated with said reduction system, whereby to transfer power from said driven shaft element to said pressure elements.

5. An improvement according to claim 4, wherein said second subassembly includes:

a first structural member including a first reaction surface;

said flexible tube mounted adjacent said first reaction surface;

a second structural member carrying said pressure rollers and

connection means associated with said first and second structural members, said connection means being constructed and arranged to provide a first, priming, position of said rollers with respect to said first reaction surface and a second, pumping, position of said rollers with respect to said first reaction surface.

6. An improvement according to claim 5, wherein said first reaction surface is generally conical with a cone axis congruent with the axis of said driven shaft and said rollers are generally conical and mounted to turn on respective roller axes, each of which is approximately parallel said cone axis, said connection means being operable to adjust the spacing between said first reaction surface and the surfaces of said rollers such that said spacing is relatively larger in said priming position and relatively smaller in said pumping position.

7. An improvement according to claim 6, wherein said connection means is constructed and arranged for;

positioning said first and second structural members in said priming position with said rollers in a first axial location with respect to said first reaction surface; and

accommodating relative axial movement of said first and second structural members into said pumping position, thereby moving said rollers into a second axial location with respect to said first reaction surface.

8. An improvement according to claim 7, wherein said first structural member comprises a cassette body element, said second structural member comprises a portion of a cassette housing, and said first and second structural members are cooperatively adapted to couple together temporarily into said priming position during an assembly operation, and to be pressed permanently into said pumping position following priming of said flexible tube.

9. An improvement according to claim 2, including an optical sensor constructed and arranged to count the number of revolutions of said rollers through said chamber during a duty cycle.

10. A peristaltic pump system, comprising:

rotating pressure rollers, each pressure roller incorporating a respective follower gear, each said respective follower gear being meshed with a drive gear, each said respective follower gear being incorporated within and constituting an element of a gear reduction system structured and arranged to revolve through a chamber with the outer surfaces of said rollers constituting pressure surfaces in contact with a flexible tube, whereby to cause positive displacement pumping action through said tube, and

a reaction surface, positioned opposite said rotating pressure elements, said flexible tube being positioned intermediate said rotating pressure elements and said reaction surface, said flexible tube being compressed by said rotating pressure elements and said reaction surface.

11. A system according to claim 10, wherein said follower gears are dimensioned relative to said drive gear to produce a reduction in rotational velocity of said rollers relative to said drive gear;

said follower gears being arranged to receive rotational force from said drive gear which receives power through a driven shaft element.

12. A system according to claim 10, wherein said pump system includes a first subassembly comprising said driven shaft element;

a second subassembly comprising said pressure rollers; and

a coupling mechanism associated with said reduction system, whereby to transfer power from said driven shaft element to said pressure elements.

13. A system according to claim 12 wherein said second subassembly includes:

a first structural member including a first reaction surface;

said flexible tube mounted adjacent said first reaction surface;

a second structural member carrying said pressure rollers and

connection means associated with said first and second structural members, said connection means being constructed and arranged to provide a first, priming, position of said rollers with respect to said first reaction surface and a second, pumping, position of said rollers with respect to said first reaction surface.

14. A system according to claim 13, wherein said first reaction surface is generally conical with a cone axis congruent with the axis of said driven shaft and said rollers are generally conical and mounted to turn on respective roller axes, each of which is approximately parallel said cone axis, said connection means being operable to adjust the spacing between said first reaction surface and the surfaces of said rollers such that said spacing is relatively larger in said priming position and relatively smaller in said pumping position.

15. The system according to claim 14, wherein said connection means is constructed and arranged for;

positioning said first and second structural members in said priming position with said rollers in a first axial location with respect to said first reaction surface; and

accommodating relative axial movement of said first and second structural members into said pumping position, thereby moving said rollers into a second axial location with respect to said first reaction surface.

16. The system according to claim 15, wherein said first structural member comprises a cassette body element, said second structural member comprises a portion of a cassette housing, and said first and second structural members are cooperatively adapted to couple together temporarily into said priming position during an assembly operation, and to be pressed permanently into said pumping position following priming of said flexible tube.

17. The system according to claim 10 wherein said reaction surface is stationary relative to said pressure rollers.