| 摘要 |
PURPOSE:To give no feeling of physical disorder to a driver in returning to neutral position by ensuring that a rear wheel steering means displaced from the neutral position in the occurrence of an abnormality can be gradually returned to the neutral position by the energized force of a neutral position returning means. CONSTITUTION:A four-wheel steering device 2 has a rear wheel steering rod 4, a neutral position returning means 6, and a servo motor 8, a clutch as a joint releasing means, and a control unit 12. The neutral position returning means 6 is disposed on the rear wheel steering rod 4, and composed of a casing and spring disposed therein, by which spring the rod is regularly energized toward the neutral position. The rod 4 is driven by the servo motor 8 to steer the rear wheels. The clutch 10 is provided between the servo motor 8 and a gear train 28, and when an abnormality occurs, it releases the joint of the rod 4 and the servo motor 8 to return the rod in the neutral position. |
