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:
Apr. 17, 2012
Filed:
Dec. 26, 2007
Kazunori Nakamura, Tsuchiura, JP;
Tsuyoshi Nakamura, Tsuchiura, JP;
Mitsuo Kihara, Kasumigaura, JP;
Hiroyuki Azuma, Ushiku, JP;
Atsushi Shimazu, Moriya, JP;
Kazunori Nakamura, Tsuchiura, JP;
Tsuyoshi Nakamura, Tsuchiura, JP;
Mitsuo Kihara, Kasumigaura, JP;
Hiroyuki Azuma, Ushiku, JP;
Atsushi Shimazu, Moriya, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A hydraulic steering unitgenerates a control pressure corresponding to the rotational quantity and rotational direction of the steering wheelon the basis of pressurized oil of a pilot pump. Signals of pressure sensorsandused to detect the control pressure, and a signal of a front operation detection unit, are inputted into a controller. A controllerand solenoid valvesandcontrol a stroke of a steering valveso that the stroke becomes larger with increase in control pressure detected by each of the pressure sensorsand. In addition, when the operation of a front work device is detected, the controllerand the solenoid valvesandcontrol the stroke of the steering valveso that the stroke becomes larger than that provided when the operation of the front work device is not detected.