| 摘要 |
A fluid pressure control valve comprises a valve housing slidably accommodating a valve spool which is responsive to an incoming fluid pressure for producing a controlled fluid pressure depending on an axial position of the spool, a biasing member disposed in the valve housing for biasing the spool in a pressure buildup direction, a reaction piston receiving the controlled fluid pressure to generate a reaction acting on the spool to move the spool in a pressure reduction direction, and an electromagnetic solenoid including a solenoid plunger having an outer diameter greater than the spool. The plunger engages the spool to move the spool in the pressure reduction direction by attraction of the solenoid. The biasing member includes a pilot piston engaging the spool and receiving the master-cylinder pressure to push the spool in the pressure buildup direction. A pressure-receiving area of the pilot piston is designed to be greater than that of the reaction piston by a predetermined amplification. |
