| 摘要 |
PURPOSE:To easily control hydraulic reaction force by controlling the flowrate of the excessive flow of a flowrate control valve that controls the exhaust flowrate of a supply pump with the use of a variable diaphragm according to the car speed and such. CONSTITUTION:A power steering device is provided with a servo valve 30 that controls the supply and exhaust of pressurized oil into a power cylinder according to the relative rotation of output shafts 23 and 21. In addition, the device is provided with a reaction force mechanism including a moving plunger 54 in the radial direction, that introduces the pressurized oil exhausted from a supply pump 60 and passing through first and second flowrate control valves 61 and 65 and is varied into the handle torque corresponding to the car speed and such. In this case, the second flowrate control valve 65 is designed to the pressure before and behind of a variable diaphragm 66 controlled according to the car speed and such can be kept constantly. Besides, a diaphragm control valve 80 that varies the diaphragm opening by the steering pressure supplying hydraulic reaction force PR to the servo valve 30 and is relieved to the low pressure side is provided in a path 46 connected to the introduction port 58. |
