| 摘要 |
PURPOSE:To get rid of any pressure unbalance in both symmetrical oil chambers as well as improve the extent of travel safety by installing such a transfer means as interconnecting these symmetrical oil chambers for a rear-wheel steering cylinder, in the case where rear wheels are locked by a rear-wheel locking means after resetting the rear wheels to a neutral state from the steered state. CONSTITUTION:A DC motor 33 is driven in either direction by a controller 31 from a detecting signal of a handwheel angle sensor 29 detecting a steering angle by a steering wheel 13, and the power is transmitted to a steering unit 37 via a reduction gear 35. With this constitution, supply or exhaust of pressure oil to or from a rear-wheel steering cylinder 45 is controlled, thereby steering each rear wheel 3. A rear-wheel locking means 61 for regulating or allowing the rear-wheel steering is installed in the rear wheels 3. In a suchlike steering gear, a selector valve 101 is interposed between the steering unit 37 and the rear-wheel steering cylinder 45. when a solenoid 105 is in nonexcitation as well as when it is so far selected to a transfer position 101a, both symmetrical cylinders 49, 51 of the rear-wheel steering cylinder 45 are made into a state of being interconnected to each other. |
