| 摘要 |
PURPOSE:To obtain a good steering sense by guiding the exhaust flowrate of a supply pump to a pilot electromagnetic relief valve controlled through a fixed diaphragm according to the car speed and such and controlling reaction force hydraulic pressure corresponding to the gear generation pressurized oil. CONSTITUTION:A power steering device is provided with a servo valve 20 that controls the supply and exhaust of pressurized oil into a power cylinder according to the relative rotation of output shafts 24 and 11. In this case, a pilot electromagnetic relief valve 60 connected through a fixed diaphragm 56 is provided at the lower stream side of a flowrate control valve 51 that constantly keeps the pressure before and behind an orifice 52 at all times in a supply path 75 that connects a supply pump for exhausting the pressurized oil in the flowrate Q0 and the supply port 26 of the servo valve 20. Besides, a main valve 55 controlled corresponding to the pressure before and behind the fixed diaphragm 56 is provided. Then, an introduction port 40 for a reaction force mechanism is connected between the fixed diaphragm 56 and relief valve 60 and an electromagnetic flowrate control valve 80 that applies the back pressure corresponding to the steering pressure is provided at the drain side of the relief valve 60. |
