| 摘要 |
PURPOSE:To drive a vehicle in the same directon with a same control operation when it is in travelling motion, by switching a selector valve, between a control valve that feeds pressure oil to a steering cylinder and an oil pressure source, in accordance with a position of the driver's seat or various states of travelling. CONSTITUTION:If a switch 44 is placed to a normal travelling position, the first selector valve 24 is set to the first position and the second selector valve 28 is set to a neutral position. When a solenoid valve 21 is placed to the first position, pressure oil from a pump P2 is fed to the first chamber in a front steering valve 16F to extend a tube 16a and select a front steering valve 11 to the second position, and pressure oil from a pump P1 is fed to an extension chamber at the right side of a front steering cylinder 7 and to a contraction chamber at the left side of said cylinder, and this causes front wheels 2 to be swivelled to the right (arrow mark A) through a piston rod 7a and knuckle 17. Because a piston 16b is moved upward by the knuckle 17, the valve 11 is reset to its neutral position and the front wheel 2 is stopped swivelling at that position. Because the valve 28 is in the neutral position, rear wheels 3 are in a state of straight travelling. |
