초록 ▼

A four-wheel steering system for motor vehicle including a front wheel steering mechanism for steering front wheels in response to a steering wheel, a rear wheel steering mechanism in accordance with the movement of the front wheels, control unit having driving condition detecting means for detectin

A four-wheel steering system for motor vehicle including a front wheel steering mechanism for steering front wheels in response to a steering wheel, a rear wheel steering mechanism in accordance with the movement of the front wheels, control unit having driving condition detecting means for detecting a vehicle driving condition and controlling the rear wheel steering mechanism, fail judging section for judging a failure of the control unit and producing a failure signal, and fail-safe control unit for controlling the rear wheel steering mechanism in a manner different from a control under a normal operation of the control unit when the control unit is in an unusual condition, and the fail judging section and/or the fail-safe control unit being provided with a plurality of actuating mechanism wherein each of the actuating mechanism can actuate the fail judging section and the fail-safe control unit independently to position the rear wheels at a neutral position.

대표청구항 ▼

A four-wheel steering system for motor vehicle including a front wheel steering mechanism for steering front wheels in response to an operation of a steering wheel, a rear wheel steering mechanism for steering rear wheels in accordance with the steered movement of the front wheels, control means hav

A four-wheel steering system for motor vehicle including a front wheel steering mechanism for steering front wheels in response to an operation of a steering wheel, a rear wheel steering mechanism for steering rear wheels in accordance with the steered movement of the front wheels, control means having driving condition detecting means for detecting a vehicle driving condition and controlling the rear wheel steering mechanism in accordance with the vehicle driving condition, fail judging means for judging of a failure of the control means and producing a failure signal denoting the failure, and fail-safe means for receiving the failure signal from the fail judging means and controlling the rear wheel steering mechanism independently from the control means when the control means is in an unusual condition, wherein the fail judging means being provided with first fail judging means and second fail judging means adapted to be actuated independently for judging different fail conditions, the control means being provided with a control unit for receiving signals from said driving condition detecting means and producing control signals to the rear wheel steering mechanism, the first fail judging means being provided in the control unit, and the second fail judging means being provided in a back up control unit independent from the control unit.