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:
Jul. 06, 1999
Filed:
Dec. 01, 1997
David E Susag, Fargo, ND (US);
Case Corporation, Racine, WI (US);
Abstract
A hydraulic circuit has first and second pumps coupled to first and second directional valves, each controlling work mechanisms such as a hydraulic cylinder and a hydraulic motor. The directional valves are in a valve assembly having a fluid passage through it. The passage includes first and second input ports and a passage closure intermediate the ports to prevent cross-feeding of the pumps. The first valve is connected to the passage between the first port and the closure and the first pump flows fluid to the first port. Similarly, the second valve is connected to the passage between the second port and the closure and the second pump flows fluid to the second port. In a more-specific embodiment, the second pump is a variable displacement pump and the first pump is a fixed displacement pump also connected to a power steering system through a priority valve. Thus, the first pump flows fluid to the power steering system as well as to the first port.