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. 08, 2013
Filed:
May. 13, 2009
Gary L. Dostal, Cedar Falls, IA (US);
Steven D. Wallestad, Cedar Falls, IA (US);
Dennis L. Jeffries, Waterloo, IA (US);
Ryan Lindsay, Waterloo, IA (US);
Gary L. Dostal, Cedar Falls, IA (US);
Steven D. Wallestad, Cedar Falls, IA (US);
Dennis L. Jeffries, Waterloo, IA (US);
Ryan Lindsay, Waterloo, IA (US);
Deere & Company, Moline, IL (US);
Abstract
A dual pump hydraulic system is provided for a vehicle driven by an internal combustion engine. The system includes a first circuit with a first high pressure pump supplying hydraulic fluid to the first subsystem at a higher pressure. The system also includes a second circuit with a second lower pressure pump supplying hydraulic fluid to the second subsystem at a second pressure. A first valve controls communication between the first pump and the second circuit. A second valve is operable to communicate the second pump with the first circuit when pressure in the first circuit is less than a second threshold pressure or when commanded by a control unit. A check valve prevents fluid flow from the first circuit back into to the second valve.