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. 25, 1978
Filed:
Mar. 23, 1977
Howard A Marsden, Pekin, IL (US);
Willard J Haak, Peoria, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A vehicle includes an auxiliary front wheel drive system including fluid motors, and a valve movable to supply fluid pressure thereto for driving thereof. A second valve is included in communication with the exhaust conduits of the motors, blocking flow therethrough when the first-mentioned valve is not supplying fluid to the motors. Further a transmission is included for regulating the fluid pressure provided to the fluid motors. Another aspect includes a pressure relief valve and means for selectively varying the relief pressure of the pressure relief valve to provide proper torque characteristics to the front wheel drive system.