| 摘要 |
PURPOSE:To improve steering stability and safety provided during switching of a fixed mode for file parking, by a method wherein a speed, at which rear wheels are steered when a running mode is switched, is decreased to prevent the occurrence of a sudden change in orientation. CONSTITUTION:A delay means 23 having large and small throttles 23a and 23c is located between a hydraulic pump 14 and a switch valve 15 of a rear wheel steering device 7 to switch a pressure, transmitted to a hydraulic actuator 11, in response to the output of a deciding means 22. A controller 16 controls the switch valve 15 with the aid of steering angle sensors 17, 19 and a car speed sensor 18. By selecting a fixed mode by means of a manual switch 20, the controller 16 steers rear wheels and front wheels in the same direction by the same amount to facilitate file parking. With the switch 20 turned OFF, the mode is restored back to an automatic control mode, but in this case, the deciding means 22 generates an output for a specified time to decrease oil pressure. This causes an actuator to operate moderately and decreases the change in orientation of a car. |
