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:
Jan. 19, 2010
Filed:
Jan. 18, 2007
Ayumu Miyajima, Chiyoda-ku, JP;
Isamu Tsubono, Chiyoda-ku, JP;
Takaomi Nishigaito, Chiyoda-ku, JP;
Toru Takahashi, Chiyoda-ku, JP;
Mitsuo Sasaki, Chiyoda-ku, JP;
Toshimitsu Sakaki, Chiyoda-ku, JP;
Tatsuo Matsumura, Chiyoda-ku, JP;
Ayumu Miyajima, Chiyoda-ku, JP;
Isamu Tsubono, Chiyoda-ku, JP;
Takaomi Nishigaito, Chiyoda-ku, JP;
Toru Takahashi, Chiyoda-ku, JP;
Mitsuo Sasaki, Chiyoda-ku, JP;
Toshimitsu Sakaki, Chiyoda-ku, JP;
Tatsuo Matsumura, Chiyoda-ku, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a power steering system comprising a power cylinder for assisting a steering power of a steering mechanism, a hydraulic pump for supplying a hydraulic pressure to the power cylinder, a first oil passage and a second oil passage connecting the power cylinder and the hydraulic pump respectively, a motor for driving the hydraulic pump, and power steering control means for calculating a command value to the motor based on the steering torque, a flow rate of the working oil supplied from a high-pressure side oil passage to a low-pressure side oil passage is restrained at the transition from the end of the steering state (lock end) of the steering mechanism to the returning. The flow-rate restraint increasingly corrects a driving current of the motor in the steering direction or limits the flow rate of the working oil.