| 摘要 |
PURPOSE:To reduce a spring constant and prevent the joint part of an oil feed pipe from showing any looseness and other troubles in the titled equipment which applies gas and oil pressure by communicating each of the gas chambers of a main actuator and a sub actuator having oil chambers each to which a hydraulic unit is connected. CONSTITUTION:If the oil pressure in a power steering unit 36 is below a specified value, opening and closing valves 27 and 28 are opened to communicate the gas chambers 8 and 23 of each pair of main and sub actuators 1, 2, 20 and 21 with each other. Since the capacities of the gas chambers become great, the spring constant may stay low and the riding on a vehicle be therefore comfortable. Once each rod 6 is forced down due to increased load to actuate a limit switch 13, direction change-over valves 33 and 34 operate so that pressure oil is fed into each of the oil pressure chambers 24 of the sub actuators to compress the gas chambers 24. Consequently, the rods 6 are stretched to maintain the vehicle at a constant height. When the oil pressure in the unit 36 is increased by turning a steering wheel, the valves 27 and 28 are closed so that the main actuators 1 and 2 only are operated, hence increasing the spring constant. As a result, the riding feel may be improved and troubles such as looseness of the joint part be prevented. |
