The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 04, 1981
Filed:
Feb. 25, 1980
Burleigh M Hutchins, North Attleboro, MA (US);
Louis Abrahams, Worcester, MA (US);
Waters Associates, Inc., Milford, MA (US);
Abstract
A pump for precise, smooth delivery of liquid, particularly in liquid chromatography systems, featuring two liquid displacement elements mounted for reciprocating movement in chambers connected in series with two check valves, one displacement element serving to accumulate some of the liquid delivered by the first element and to deliver the accumulated liquid while the first element is refilling. Also disclosed is a fluid storage device for smoothing pulses from the pump comprising a flattened tube wound into a helix and placed within an annulus formed by an inner and an outer cylindrical wall. These cylindrical walls maintain the flattened tubing from expanding beyond its elastic strain limit.