| 摘要 |
PURPOSE:To minimize recoiling of a main valve at the time of stopping the same, by use of the speed difference of the motion of a movable sleeve formed with an internal bore communicated with both of a first main circuit and a second main circuit and the main valve inserted into the internal bore of the sleeve in a freely slidable manner. CONSTITUTION:When the pressure rising speed of a fluid in a first main circuit 3 becomes higher than a prescribed value, the speed of motion of a main valve 10 becomes higher than the speed of motion of a movable sleeve 5. Resultantly, the top of a large-diameter head 11 of the main valve 10 is disengaged from a valve seat 6 and a passage 1a is communicated with a second main circuit 4, so that part of the fluid in the passage 1a is passed to the second main circuit 4 and the pressure of fluid in the first main circuit 3 is lowered. In case of stopping an actuator 39 that has been in operation, the top of a large-diameter head 11' of a main valve 10' is disengaged from a valve seat 6' of a movable sleeve 5' when the braking force becomes greater than the inertial force, so that the pressure of fluid in the passage 1a is lowered. |
