| 摘要 |
PURPOSE:To obtain a device high in reliability and unconstrained in layout by providing a rear wheel solenoid control valve with a negative-phase mode change-over position and an in-phase mode change-over position maintained in relation to the actuation of a metering cylinder. CONSTITUTION:When a steering wheel 11 is turned largely, a metering cylinder MC is put in action to actuate a pilot cylinder CM feeding it with delivered fluid pressure so as to change a rear wheel solenoid control valve RV over to the negative-phase mode. If the turning angle of the steering wheel 11 is small, fluid is not delivered as the metering cylinder MC maintains the deadband, and when the speed exceeds the fixed speed, a controller C excites solenoids 43, 44 so as to change the rear wheel solenoid control valve RV over to the in-phase mode. When the steering wheel is turned largely, the steering directions of front and rear wheels 14, 50 are reversed in the case of low speed running, and in small turning, the steering directions of the front and rear wheels 14, 15 are made the same in the case of high speed running. |
