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. 17, 2008
Filed:
Oct. 11, 2005
Jun Soeda, Kanagawa, JP;
Tadaharu Yokota, Kanagawa, JP;
Jun Soeda, Kanagawa, JP;
Tadaharu Yokota, Kanagawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A power steering apparatus includes a hydraulic power cylinder, a reversible pump including a first outlet connected with a first pressure chamber of the power cylinder through a first fluid passage, and a second outlet connected with a second pressure chamber of the power cylinder through a second fluid passage, and a motor for driving the pump. A controller controls the motor in accordance with a sensed steering force. There is further provided a connection passage connecting the first and second fluid passages together, and a closing valve disposed in the connection passage. The controller sends a first current to a coil of the valve to close the connection passage by moving an armature, to send a second current lower than the first current to the coil after the connection passage is closed, and to deenergize the coil to open the connection passage.