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:
Jan. 09, 1990
Filed:
Apr. 13, 1989
G Earl Maroney, Clarkston, MI (US);
Mark W Dallas, Ortonville, MI (US);
Christopher West, Clawson, MI (US);
John A Diemer, Auburn Hills, MI (US);
Mark B Chamberlin, Royal Oak, MI (US);
M. C. Aerospace Corporation, Lake Orion, MI (US);
Abstract
A flow-sensing shutoff valve connectable between upstream and downstream portions of a hydraulic system comprises a valve body having pressure entrance and return exit ports connectable to the upstream portion of the system, and pressure exit and return entrance ports connectable to the downstream portion of the system. A valve element within the valve body is movable between a normally open position in which the pressure and return entrance and exit ports are connected by separate passages in the valve body, and a closed position in which the passages are blocked. Pressure and return flowmeters are adapted to sense fluid flow in the passages between the valve element and the pressure exit port and the return exit port, respectively. Flow rate signals from the flowmeters are compared in a control circuit and in response to a certain flow differential, an output signal drives an actuator which moves the valve element to closed position, isolating the downstream from the upstream portion of the hydraulic system.