| 摘要 |
PURPOSE:To prevent the occurrence of sudden steerage for rear wheels in time of trouble happening in a hydraulic system, by making an actuator, which makes these rear wheels steer in the reverse direction to a front-wheel steering direction in time of steering front wheels, nonoperational when a front steering angle is below the fixed value or a car speed is above the fixed one. CONSTITUTION:During steerage of front wheels 1, a tie rod 5 makes a piston rod 41 and a piston 35 of a piston valve body 34. However, at a region where each steering angle of these front wheels 1 is below the fixed value as in drining at high speed, the piston 35 is not largely moved, insomuch that it collides in taction with valve discs 36 and 37. Therefore, these valve discs 36 and 37 are kept in illustrated position where makes circuits 29 and 30 to be interconnected to chambers 22 and 23 at both sides of an actuator 18 for steering rear wheels 2 lead to a drain circuit 40. Accordingly, at the region where the front wheel steering angle is below the fixed value, even if oil pressure rises so abnormally, this actuator 18 will not work whereby these rear wheels 2 are not steered at all. At the region where the front steering angle is above the fixed one, the piston 35 collides in taction with these valve discs 36 and 37, moving the said valve body so that these rear wheels 2 are steered. |
