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:
Jun. 15, 1976
Filed:
Jun. 04, 1975
William D McMillan, Joliet, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A hydraulic power system having a plurality of variable displacement pumps for supplying pressurized fluid for manipulation of an implement includes control means operative to automatically adjust pump displacement to the output horsepower of a prime mover driving the pumps of a system. The control system includes underspeed valve means responsive to a deviation in the speed of the prime mover from a predetermined normal speed to transmit a fluid pressure signal to a servo control means for adjusting the displacement of the pumps. The underspeed valve means includes adjusting means for adjusting the underspeed valve to respond to a deviation from other engine speeds different from the normal operating speed.