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. 14, 2016
Filed:
Aug. 09, 2013
Caterpillar Inc., Peoria, IL (US);
Susan E. Bieker, Minooka, IL (US);
Eric P. Jakubiak, Aurora, IL (US);
Dennis R. Barber, Plainfield, IL (US);
John J. Kaufman, Yorkville, IL (US);
Edward W. Mate, Manhattan, IL (US);
Scott D. Vollmer, Naperville, IL (US);
Michael D. Hudson, Mount Zion, IL (US);
Moses I. Akpan, Moline, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A hydraulic fan circuit is provided. The hydraulic fan circuit includes a tank, a motor having a fluid inlet and a fluid outlet and a pump to draw fluid at a low pressure from the tank and discharge the fluid at elevated pressures to the motor via the fluid inlet. The hydraulic fan circuit further includes a directional control valve disposed between the fluid outlet of the motor and the tank. The directional control valve is operable to move between a flow blocking position and a flow passing position. Further, the directional control valve is configured to reduce a positive speed of the motor below a lowest positive speed attainable through control of pump output. Furthermore, the hydraulic fan circuit includes a pressure control circuit configured to provide a pilot fluid flow at varying pressure to move the directional control valve.