PULSEFREE PERISTALTIC PUMP

• US 3,726,613 A
• Filed: 10/12/1970
• Issued: 04/10/1973
• Est. Priority Date: 10/12/1970
• Status: Expired due to Term

• Current Assignee: Wolf Von Casimir
• Original Assignee: Wolf Von Casimir
• Inventors: von Casimir, Wolf
• Primary Examiner(s): Freeh, William L.
• Assistant Examiner(s): Gluck, Richard E.
• Application Number:
  US05/080,115
• Time in Patent Office: 911 Days
• Field of Search: 417/474,475,476,477
• US Class Current: 417/477.1
• CPC Class Codes: F04B 11/0075 connected in series
• 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 43/1253 by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing

Abstract

To smooth the pulsations in the flow rate of a fluid conveyed by a peristaltic pump, a cam-controlled pusher is synchronized with the driving elements (rollers or plungers) acting upon the wall of a flexible tube to constrict that wall, at a location downstream of the driving elements, when these elements advance the fluid toward the tube outlet and to allow its expansion at the beginning of every new operating cycle when a new pressure wave is initiated at a location remote from that outlet.

Claims

1. A peristaltic pump comprising:

a tube provided with a flexible wall having an inlet for a fluid to be conveyed, an outlet for said fluid and an operating zone between said inlet and outlet;

driving means periodically engageable with said tube along said operating zone for deforming the wall thereof to advance said fluid toward said outlet in a series of recurrent operating cycles, said driving means comprising a set of driving elements and shaft means for intermittently moving each driving element into contact with said tube to obstruct same completely at a point advancing from said inlet toward said outlet in the course of an operating cycle;

a pusher movable substantially at right angles to the wall of said tube at a location downstream of said zone, said pusher being capable of only a partial blocking effect; and

cam means synchronized with said driving means for actuating said pusher to constrict said tube upstream of said outlet at a stage of each operatinc cycle in which the driving element closest to said pusher is substantially fully withdrawn from said wall for progressively allowing the tube to expand at said location during the remainder of an operating cycle, thereby smoothing the flow of said fluid through said outlet.

2. A pump as defined in claim 1 wherein said cam means is mounted on said shaft means.

3. A pump as defined in claim 2 wherein said driving elements are a plurality of rollers and a rotatable support therefor coaxially mounted with said cam means for moving each roller in contact with said tube along an arc centered on said shaft means.

4. A peristaltic pump comprising:

a tube provided with a flexible wall having an inlet for a fluid to be conveyed, an outlet for said fluid and an operating zone between said inlet and outlet, said operating zone being substantially semicircularly curved about an axis;

a support rotatable about said axis;

a pair of diametrically opposite driving rollers mounted on said support for alternate engagement with said tube along said operating zone for deforming the wall thereof to advance said fluid toward said outlet in a series of recurrent operating cycles by obstructing said tube completely at a point advancing from said inlet toward said outlet in the course of an operating cycle;

a pusher movable substantially at right angles to the wall of said tube at a location downstream of said zone with a partial blocking effect; and

cam means on said shaft for actuating said member to constrict said tube upstream of said outlet at the beginning of each operating cycle and for progressively allowing the tube to expand at said location during the remainder of an operating cycle, thereby smoothing the flow of said fluid through said outlet.