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:
May. 26, 1998
Filed:
Oct. 26, 1995
Francedilla.ois Couillard, Noyalo, FR;
Dominique Garnier, Orgeval, FR;
Francois Couillard, Noyalo, FR;
Institute Francais du Petrole, Rueil-Malmaison, FR;
Abstract
A pumping system in accordance with the invention comprises n (n.gtoreq.1) piston or diaphragm primary pumping modules (P1 to Pn) including each at least one pumping unit, connected by means of unidirectional valves (V11-V1n) respectively to n tanks (R1-Rn) containing fluids, a collecting head (CH) receiving the fluids delivered by the various primary modules, and a secondary piston pumping unit (S) for discharging the mixture of fluids collected in this head with a substantially constant flow rate. The pistons are shifted alternately for example by the translation motion of endless screws (9) driven by motors (12). A control set (17-20) associated with position detectors (AC1-ACn) and pressure detectors (C1 to Cn, Cs) proportion the fluids injected and adjust the phases, the piston strokes and their velocities in order to obtain a substantially constant discharge rate. Each primary module can also comprise a second pumping module also allowing a constant rate to be obtained during the suction phase. The invention has application to liquid chromatography.