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:
Mar. 05, 1985
Filed:
Mar. 24, 1983
Howard E Chana, Troy, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
There is disclosed a multistage gear pump and control valve arrangement comprising two hydraulic gear pump sets each having a suction port connected to a common sump and a discharge port for delivering hydraulic fluid to a circuit line. Only one of the discharge ports is continuously open to the circuit line while a check valve operates to connect the other of the discharge ports to the circuit line and prevent reverse flow. A regulator valve regulates the pump discharge to the circuit line by diverting fluid therefrom in response to circuit line pressure below a predetermined setting while both the discharge ports are delivering fluid thereto and by being responsive to circuit line pressures thereabove to connect the other discharge port to the sump to thereby relieve the associated gear pump set of hydraulic work while again regulating the pump discharge to the circuit line by diverting fluid therefrom but with only the one discharge port delivering fluid thereto.