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:
Aug. 11, 2015
Filed:
Dec. 27, 2011
Hiroyasu Nishikawa, Tokyo, JP;
Sei Shimahara, Tokyo, JP;
Manabu Nakanishi, Hyogo, JP;
Masashi Shibata, Hyogo, JP;
Hiroyasu Nishikawa, Tokyo, JP;
Sei Shimahara, Tokyo, JP;
Manabu Nakanishi, Hyogo, JP;
Masashi Shibata, Hyogo, JP;
Caterpillar SARL, Geneva, CH;
Abstract
A controller controls the solenoid-operated variable pressure relief valves that are provided to control, at set pressures that can be electrically commanded, pressure of hydraulic oil fed to an attachment cylinder. The controller is provided with a control logic that is capable of controlling the aforementioned solenoid-operated variable pressure relief valves. The control logic performs the aforementioned calculation by compensating for pressure override characteristics of each solenoid-operated variable pressure relief valve based on input signals related to the set relief pressure for and a relief valve passing flow rate of the solenoid-operated variable pressure relief valve, and outputting to the solenoid-operated variable pressure relief valve command signals related to the adjusted set relief pressure resulting from the compensation of the pressure override characteristics.