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, 1988
Filed:
Sep. 12, 1985
Akihiko Miyoshi, Hiroshima, JP;
Mazda Motor Corporation, , JP;
Abstract
A four-wheel steering system for a vehicle comprises a steering wheel, a front wheel turning mechanism for turning front wheels in response to operation of the steering wheel, and a rear wheel turning mechanism which turns rear wheels in response to operation of the steering wheel and is provided with an electric actuator for changing the position of a movable member the position of which determines a rear wheel turning angle ratio which is the ratio of the turning angle of the rear wheels to the turning angle of the front wheels for a given turning angle of the steering wheel. A control circuit receives a vehicle speed signal from a vehicle speed sensor and controls the electric actuator according to the detected vehicle speed so that a target rear wheel turning angle ratio determined in advance according to the vehicle speed is obtained. A preset vehicle speed detector detects a preset vehicle speed and a rear wheel turning angle ratio detector detects the actual rear wheel turning angle ratio. A correction circuit which receives signals from the preset vehicle speed detector and the rear wheel turning angle ratio detector and controls the electric actuator to change the position of the movable member so that the actual rear wheel turning angle ratio coincides with the target rear wheel turning angle ratio at said preset vehicle speed.