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:
Feb. 16, 1988
Filed:
Mar. 16, 1987
Abstract
A motor-driven power steering system for a vehicle wherein vehicle speed and operator-induced steering torque are detected for the control of power-assisting steering operation; a vehicle-speed sensor for detecting the vehicle speed to generate an output signal representative of the detected vehicle speed; a motor connected to be energized by a battery to transmit a force to the steerable road wheels for power assisting steering motion caused by the operator through the steering wheel; a first electromagnetic sliding clutch for controlling the power-assisting force transmitted from the motor to the steerable road wheels; a second electromagnetic switching clutch connected to be switched off for interrupting the transmission of the power-assisting force from the motor toward the steerable road wheels when the vehicle speed increases above a prescribed level, and switched on for transmission of the power-steering force therebetween when the vehicle speed decreases below the prescribed level; and a control unit connected to receive output signals from the torque sensor and the vehicle-speed sensor for controlling respective running and switching operations of the motor and the first sliding clutch in such a manner that the power-assisting force transmitted from the motor to the steerable road wheels through the first sliding clutch is gradually decreased before the second switching clutch is switched off, and gradually increased after the second switching clutch is switched on.