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:
Jul. 31, 2001
Filed:
Jul. 26, 1999
Hirotetsu Sonoda, Saitama, JP;
Tatsuya Fukushima, Saitama, JP;
Abstract
In a power steering device, a pump supplies a pressure fluid. A power cylinder has left and right chambers and is driven in accordance with a pressure difference between a pressure fluid supplied to the left chamber and that to the right chamber. A flow channel selector valve selectively switches a supply direction of the pressure fluid from the pump to the chambers of the power cylinder in response to steering operation of a steering wheel. Fluid paths connect the flow channel selector valve and the corresponding chambers of the power cylinder to each other. Variable restrictors are disposed in the fluid paths, respectively, to control flow rate of the pressure fluid from the power cylinder to the flow channel selector valve. Check valves are respectively connected to the fluid paths in parallel to the corresponding variable restrictors to prevent a flow of the pressure fluid from the power cylinder to the flow channel selector valve. First and second check valves are opened when the fluid pressure in the right and let fluid paths, respectively, is high.