Pump chamber and valve assembly

• US 5,551,850 A
• Filed: 05/11/1995
• Issued: 09/03/1996
• Est. Priority Date: 03/09/1994
• Status: Expired due to Fees

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Heim, Warren P., Anderson, Robert L., Williamson, Mark E., Stracener, Steve W., Newbrough, Jerry W., Castleberry, Jeffrey P.
• Primary Examiner(s): KORYTNYK, PETER G
• Application Number:
  US08/439,316
• Time in Patent Office: 481 Days
• Field of Search: 417/474, 417/478, 417/479, 417/480, 417/477.1, 417/477.2, 417/477.12, 604/153
• US Class Current: 417/474
• CPC Class Codes: A61M 39/281 Automatic tube cut-off devices, e.g. squeezing tube on detection of air
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: A61M 5/14228 with linear peristaltic action, i.e. comprising at least three pressurising members or a helical member
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• 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

Abstract

A medical infusion pump (10) using a pump chamber cassette (86) has a housing (20,22) defining a pump chamber cassette receptacle (84) and a pump driving mechanism (250) for propelling liquid through the pump chamber cassette. A door (50) holds the pump chamber cassette (86) within the cassette receptacle (84) in an operative position relative to the driving mechanism (250). The cassette includes an elastomeric conduit (132), a frame (134) and clips (146,148) for attaching the elastomeric conduit (132) to the frame (134) for holding the elastomeric conduit (132) in a select position relative to the pump driving mechanism (250) of the infusion pump upon placement of the cassette (86) in an operative position relative to the pump driving mechanism (250). An anti-free flow device (136,138) includes the flexible conduit (132) received between an anvil (182) fixedly attached to the frame (134) and a pincher (132) attached to the frame (134), the pincher (138) being movable between a first position biasing the pincher (138) against the anvil (182) to occlude a lumen (150) of the elastomeric conduit (132) and a second position for eliminating the bias of the pincher (138) against the anvil (182) so as to not occlude the lumen (150) of the elastomeric conduit (132). The elastomeric conduit (132) is made of an elongate elastomeric robe having an inlet valve portion (142) and an outlet valve portion (144) made of a furst material and a chamber portion (140) disposed therebetween, the chamber portion being made of a second material. The first material has a durometer of less than a durometer of the second material. The chamber portion (140), inlet valve portion (142) and the outlet valve portion (144) may have a football-shaped cross-section.

Claims

1. In a peristaltic infusion pump having a housing defining a pump chamber cassette, the pump chamber cassette including a pump chamber assembly having a lumen, the housing further containing a pump driving mechanism including at least an inlet and an outlet pincher valve, means for maintaining the pump chamber cassette in an operative position relative to the pump driving mechanism and means for actuating the pump driving mechanism pincher valves to constrict the lumen of the pump chamber at spaced points along the pump chamber assembly by compressing the pump chamber assembly against a platen to propel liquid through the pump chamber assembly, an improved pump chamber cassette comprising:

a pump chamber assembly comprising an elastomeric tube having an inlet valve portion and an outlet valve portion made of a first material and a tubular chamber portion disposed therebetween, the chamber portion being made of a second material, there being a lumen through the inlet and outlet valve portions and the chamber portion, the first material having a durometer less than a durometer of the second material, one of the valve portions and the chamber portion having a football-shaped cross section;

a rigid frame; and

means for attaching the elastomeric tube to the frame, the attaching means maintaining the elastomeric tube between the valve pinchers and the platen with the minor axis of the football-shaped cross-section aligned parallel to the direction of the movement between the valve pinchers and the platen with the cassette received in the operative position within a cassette receptacle.

2. The improvement pump chamber cassette of claim 1 wherein the attaching means comprises:

clips spaced lengthwise along the elastomeric tube;

means bonding the clips to the elastomeric tube; and

cooperating means between the clips and the rigid frame for fastening the clips to the rigid frame in a spaced relation.

3. The improvement pump chamber cassette of claim 2 wherein the elastomeric tube is made of polyvinylchloride.

4. The improved pump chamber cassette of claim 1 wherein the peristaltic infusion pump pumping mechanism further includes a plunger intermediate the inlet and outlet pincher valves and the inlet valve portion and the outlet valve portion have football-shaped cross-sections and the pump chamber portion has a round cross-section, the inlet valve portion, the pump chamber portion and the outlet valve portion being spaced so that with the pump chamber cassette in the operative position within the pump chamber cassette receptacle, the inlet valve portions proximate the inlet pincher valve, the chamber portion is proximate the plunger and the outlet valve portion is proximate the outlet pincher valve.

5. The improved pump chamber cassette of claim 1 wherein the first material is polyvinylchloride and the second material is polyurethane.

6. The improved pump chamber cassette of claim 5 wherein the chamber portion has a football-shaped cross-section.

7. A pump chamber assembly for use with a medical infusion pump, the medical infusion pump having a housing defining a pump chamber receptacle, the housing further containing a pump driving mechanism including an inlet pincher valve, an outlet pincher valve and a plunger intermediate the inlet and outlet pincher valves, means for actuating the pump driving mechanism to propel liquid through the pump chamber assembly, and means for maintaining the pump chamber assembly within the pump chamber receptacle in an operative position relative to the pump driving mechanism, the pump chamber assembly comprising:

an elongate elastomeric tube having a tubular inlet valve portion and a tubular outlet valve portion and a tubular chamber portion disposed therebetween, the inlet and outlet valve portions having a wall thickness greater than the wall thickness of the chamber portion, the inlet valve portion, the outlet valve portion and the chamber portion being spaced so that with the pump chamber in an operative position within the pump chamber receptacle the inlet valve portion is proximate the inlet pincher valve, the chamber portion is proximate the plunger and the outlet valve portion is proximate the outlet pincher valve.

8. The pump chamber assembly of claim 7 wherein the inlet and outlet valve portions are made of a first material and the chamber portion is made of a second material, the first material having a durometer less than a durometer of the second material.

9. The pump chamber assembly of claim 8 wherein the first material is polyvinylchloride and the second material is polyurethane.