Self loading peristaltic pump tube cassette

• US 5,445,506 A
• Filed: 12/22/1993
• Issued: 08/29/1995
• Est. Priority Date: 12/22/1993
• Status: Expired due to Term

• Current Assignee: Fenwal Incorporated (Fresenius SE & Co. KGaA)
• Original Assignee: Baxter International Inc.
• Inventors: Patno, Timothy J., West, Richard L., Chapman, Arthur S., Afflerbaugh, Richard L.
• Primary Examiner(s): Bertsch, Richard A.
• Assistant Examiner(s): Korytnyk, Peter G.
• Application Number:
  US08/172,130
• Time in Patent Office: 615 Days
• Field of Search: 417/474, 417/475, 417/476, 417/477 R, 417/477 F, 417/477 G, 417/477 B, 417/477 R, 417/477.1, 417/477.7, 417/477.8, 417/477.3, 604/153
• US Class Current: 417/477.2
• CPC Class Codes: A61M 1/30 Single needle dialysis ; Reciprocating systems, alternately withdrawing blood from and returning it to the patient, e.g. single-lumen-needle dialysis or single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/303 having a reservoir for treated blood to be returned
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36224 with sensing means or components thereof
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362261 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 1/362265 Details of valves
• CPC Class Codes: A61M 1/362266 Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/3693 using separation based on different densities of components, e.g. centrifuging
• CPC Class Codes: A61M 1/3696 with means for adding or withdrawing liquid substances during the centrifugation, e.g. continuous centrifugation
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• 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

Abstract

A self-loading peristaltic pumping apparatus includes a pump race for receiving a tubing loop, a pump rotor carrying a roller, and a drive mechanism for rotating the rotor within the pump race. The apparatus also includes a roller locating mechanism that moves the pump roller between a retracted position, free of contact with the received tubing loop, and an extended position, at least partially within the pump race for operative contact with the received tubing loop. The apparatus includes at least one tubing guide element carried by the rotor. The guide element extends from the rotor at least partially into the pump race. The guide element serves during rotation of the rotor with the roller in its retracted position, for contacting the received tubing loop to orient the tubing loop within the pump race.

Claims

1. A peristaltic pumping apparatus comprising

a peristaltic pumping element including a pump race for receiving a tubing loop, a pump rotor carrying a roller, and a drive mechanism for rotating the rotor within the pump race,

a loading assembly for the peristaltic pumping element comprising

a roller locating mechanism that moves the pump roller between a retracted position free of contact with the received tubing loop and an extended position at least partially within the pump race for operative contact with the received tubing loop,

at least one tubing guide means carried by the rotor and extending from the rotor at least partially into the pump race, the tubing guide means being operative, during rotation of the rotor with the roller in its retracted position, for contacting the received tubing loop to orient the tubing loop within the pump race, and

a control mechanism coupled to the drive mechanism and the roller locating mechanism, the control mechanism being operative

(i) in a loading mode for actuating the drive mechanism to rotate the rotor while actuating the roller locating mechanism to maintain the roller into its retracted position so that contact between the guide means and the received tubing loop moves the tubing loop into a desired orientation within the pump race, and

(ii) in a pumping mode for actuating the drive mechanism while actuating the roller locating mechanism to maintain the roller into its extended position so that contact between rotating roller and the tubing loop within the race pumps fluid through the tubing loop.

3. An apparatus according to claim 1 or 2

wherein the guide means is located near the roller.

4. An apparatus according to claim 1 or 2

wherein the roller includes an upper region and a lower region, and

wherein the tubing guide means includes a guide prong extending from the rotor alongside the upper region of the roller.

5. An apparatus according to claim 1 or 2

wherein the tubing guide means includes a pair of guide prongs spaced along opposite sides of the roller.

6. An apparatus according to claim 5

wherein the roller includes an upper region and a lower region, and

wherein the guide prongs extend from the rotor alongside the upper region of the roller.

2. A peristaltic pumping apparatus comprising

a peristaltic pumping element including a pump race for receiving a tubing loop, a pump rotor carrying a roller, and a drive mechanism for rotating the rotor within the pump race,

a loading assembly for the peristaltic pumping element comprising

a pump tube holder-including a body and means on the body for supporting a flexible tubing loop in an erect, outwardly bowed position for placement within the pump race,

a roller locating mechanism for moving the pump roller between a retracted position outside the pump race and an extended position at least partially within the pump race,

at least one guide means carried by the rotor and extending from the rotor at least partially into the pump race, the guide means being operative, during rotation of the rotor with the pump roller in its retracted position, for contacting the tubing loop placed within the pump race to orient the tubing loop within the pump race, and

a control mechanism coupled to the drive mechanism and the roller locating mechanism, the control mechanism being operative

(i) in a loading mode for actuating the drive mechanism to rotate the rotor while actuating the roller locating mechanism to maintain the roller into its retracted position so that contact between the guide means and the tubing loop moves the tubing loop into a desired orientation within the pump race, and

(ii) in a pumping mode for actuating the drive mechanism while actuating the roller locating mechanism to maintain the roller into its extended position so that contact between rotating roller and the tubing loop within the race pumps fluid through the tubing loop.

7. An apparatus according to claim 2

wherein the pump rotor rotates about an axis, and

wherein the body of the pump tube holder has a surface that, when the tubing loop is in the desired orientation within the pump race, lies in a plane generally perpendicular to the rotational axis, wherein the tubing loop support means extends outside the body at an acute angle relative to the surface to compress the tubing loop when the tubing loop is in the desired orientation within the pump race.