Peristaltic pump

Abstract

A peristaltic pump is provided herein including: a rotatable drive plate; a closed-loop channel; a fluid inlet located at a first location along the channel; a fluid outlet located at a second location along the channel, spaced from the first location, wherein a first portion of the channel extends between the fluid inlet and the fluid outlet, and a second portion of the channel, separate from the first portion of the channel, extends between the fluid outlet and the fluid inlet; a flexible membrane extending between, and fluidically connecting, the fluid inlet and the fluid outlet, the flexible membrane defining a closed fluid path between the fluid inlet and the fluid outlet along the first portion of the channel; and, a first roller captively disposed between the channel and the drive plate such that rotation of the drive plate causes the first roller to traverse the channel, the first roller causing downward deflection of the flexible membrane in passing therealong to constrict the closed fluid path in displacing fluid within the closed fluid path from the fluid inlet to the fluid outlet. Advantageously, the subject invention provides a planar peristaltic pump having a drive plate overlaying the fluid path allowing for top-down assembly with parts assembled along a single vertical axis.

What is claimed is: 
     
         1 . A peristaltic pump comprising:
 a rotatable drive plate;   a closed-loop channel, wherein the drive plate includes a first face facing the channel, first and second recesses being formed spaced apart in the first face;   a fluid inlet located at a first location along the channel;   a fluid outlet located at a second location along the channel, spaced from the first location, wherein a first portion of the channel extends between the fluid inlet and the fluid outlet, and a second portion of the channel, separate from the first portion of the channel, extends between the fluid outlet and the fluid inlet;   a flexible membrane extending between, and fluidically connecting, the fluid inlet and the fluid outlet, the flexible membrane defining a closed fluid path between the fluid inlet and the fluid outlet along the first portion of the channel; and,   a first roller captively disposed between the channel and the drive plate, the first roller being seated in the first recess, and, a second roller captively disposed between the channel and the drive plate, the second roller being seated in the second recess, wherein rotation of the drive plate causes interference between the drive plate and the first roller and causes interference between the drive plate and the second roller, resulting in the first and second rollers traversing the channel, the first and second rollers each causing downward deflection of the flexible membrane in passing therealong to constrict the closed fluid path in displacing fluid within the closed fluid path from the fluid inlet to the fluid outlet.   
     
     
         2 . The peristaltic pump as in  claim 1 , wherein the second portion of the channel does not overlap any portion of the closed fluid path. 
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . The peristaltic pump as in  claim 1 , wherein the first face has a sufficient diameter to overlap diametrically-opposed portions of the channel. 
     
     
         6 . The peristaltic pump as in  claim 1 , wherein the first roller is ball shaped. 
     
     
         7 . The peristaltic pump as in  claim 1 , wherein the first roller is barrel shaped. 
     
     
         8 . The peristaltic pump as in  claim 1 , wherein the first roller is block shaped. 
     
     
         9 . The peristaltic pump as in  claim 1 , wherein the first roller is conical shaped. 
     
     
         10 . (canceled) 
     
     
         11 . The peristaltic pump as in  claim 1 , further comprising a motor for rotating the drive plate. 
     
     
         12 . The peristaltic pump as in  claim 1 , wherein the flexible membrane is secured to portions along the channel. 
     
     
         13 . The peristaltic pump as in  claim 1 , wherein the channel is generally disposed in a first plane, and, wherein the drive plate includes a first face generally parallel to the first plane. 
     
     
         14 . The peristaltic pump as in  claim 1 , wherein the flexible membrane defines the closed fluid path with adjacent portions of a base plate. 
     
     
         15 . The peristaltic pump as in  claim 1 , further comprising an annular cage having a lower face facing the channel and an upper face facing away from the channel, a first seat being formed in the lower face for receiving the first roller, a first opening being formed in the upper face in alignment with the first seat to allow a portion of the first roller to protrude from the upper face with the first roller seated in the first seat. 
     
     
         16 . The peristaltic pump as in  claim 15 , wherein the drive plate includes a first face facing the upper face, a first recess being formed in the first face to receive the portion of the first roller protruding from the upper face. 
     
     
         17 . The peristaltic pump as in  claim 16 , wherein the cage is independently rotatable from the drive plate. 
     
     
         18 . The peristaltic pump as in  claim 1 , wherein a third roller is provided captively disposed between the channel and the drive plate such that rotation of the drive plate causes the third roller to traverse the channel, the first, second and third rollers being evenly spaced about the channel. 
     
     
         19 . The peristaltic pump as in  claim 1 , wherein the flexible membrane defines a tube. 
     
     
         20 . The peristaltic pump as in  claim 1 , further comprising a spring disposed to prestress the drive plate towards the first and second rollers.