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, 2011
Filed:
Feb. 20, 2007
Hiroyasu Nishikawa, Tokyo, JP;
Sei Shimahara, Tokyo, JP;
Hiroyasu Nishikawa, Tokyo, JP;
Sei Shimahara, Tokyo, JP;
Caterpillar S.A.R.L., Geneva, CH;
Abstract
A fluid pressure circuit that can, in either case where a first actuator that is fed from a first pump or a second actuator that is fed from a second pump is operated, by allowing feeding of the hydraulic fluid to a specific actuator from either the first or second pump, improve interlockability with the specific actuator. A control valve is incorporated with a plurality of first-group spools fed from a drive pump and a plurality of second-group spools fed from an idle pump. A solenoid selector valve unit switches a pilot line of a second-group tool controlling spool to a communicating state at the time of detection of a spool operation by a first pressure switch and switches a pilot line of a first-group tool controlling spool to a communicating state at the time of detection of a spool operation by a second pressure switch.