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. 19, 1987
Filed:
Dec. 14, 1984
Arvid L Nelson, Quincy, IL (US);
Cooper Industries, Inc., Houston, TX (US);
Abstract
A pumping system for producing uniform discharge and suction rates includes a pump connected to a supply of hydraulic fluid to deliver hydraulic control fluid at a selectable flow rate to a proportioning valve. The proportioning valve divides the flow of hydraulic fluid into two resulting flows, each of which is utilized via a four-way valve to drive a piston within a hydraulic cylinder. The positions of the pistons within the cylinders are detected and used to control the proportioning valve such that each piston is imparted with a velocity that varies in a sinusoidal manner in response to the hydraulic fluid delivered to it by the porportioning valve. Sensing of the piston positions and control of the proportioning valve may be accomplished mechanically by a system of cams driven by the pistons, or electronically by a microprocessor receiving signals from transducers coupled to the pistons. The speed of operation of the overall system is adjustable in response to the rate of delivery of hydraulic control fluid from the hydraulic pump.