| 摘要 |
PURPOSE:To slowly move a main valve element at the time of opening and closing operation by controlling a connecting path between a pressure intensifying chamber provided with buffer means for controlling the moving speed of the main valve element and the secondary port side by a pilot valve element. CONSTITUTION:When a pilot valve element 13 is operated by electromagnetic driving to open a valve seat 12, pressure in the periphery of a bellows 7 decreases to be lowered to the secondary pressure P2, so that force in the valve opening direction acts on a main valve element 6. A fluid with pressure P1, however, remains in the bellows 7 to resist the valve opening operation of the main valve element 6. The residual pressure in the bellows 7 gradually escapes through an equalizing hole 8 to the outside of the bellows 7 and finally becomes equal to the secondary pressure P2. As the pressure in the bellows 7 is lowered, the main valve element 6 is gradually separated from a valve seat 5.
|
