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:
Oct. 04, 2016
Filed:
Dec. 07, 2011
Hiroyuki Azuma, Tsuchiura, JP;
Tsuyoshi Nakamura, Tsuchiura, JP;
Hidenobu Tsukada, Tsuchiura, JP;
Kensuke Sato, Tsuchiura, JP;
Yasuo Okano, Tsuchiura, JP;
Hiroyuki Azuma, Tsuchiura, JP;
Tsuyoshi Nakamura, Tsuchiura, JP;
Hidenobu Tsukada, Tsuchiura, JP;
Kensuke Sato, Tsuchiura, JP;
Yasuo Okano, Tsuchiura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A relief pressure control system is provided with a controller for outputting, responsive to an adjustment signal output from a dial switch, a control signal to control a relief pressure of a variable solenoid relief valve, a display unit for displaying, responsive to display signals outputted from the controller, a relationship between a circuit pressure output from a pressure sensor and a pressure required by a hydraulic cylinder, and a control device constituting a start instruction unit for instructing a start of control of the variable solenoid relief valve. Stop valves are arranged in sections of main lines, which communicate a directional control valve and the hydraulic cylinder with each other, to open or close the section. The sections are located between positions on the main lines, where the variable solenoid relief valves are connected to the main lines, respectively, and the hydraulic cylinder.