| 摘要 |
PURPOSE:To prevent chattering of a valve, by pressing a ball onto a valve seat by the intermediary of a cup-shaped guide vane member for receiving the ball in its recessed portion in a freely rotatable manner, and providing a cylindrical member having an outer diameter smaller than the diameter of the opening of the valve seat and an auxiliary spring for pressing the cylindrical member onto the ball against the ball pressing force. CONSTITUTION:A guide 9 is fixed to a main body 1 for guiding a rod 8 in a freely slidable manner, and the lower end faces of a bellows 6 and a bellows support 7 are fitted in a recess 5a of a guide vane member 5 for keeping a ball 4 at the central position. The ball urging force is applied by a means consisting of the bellows 6 and a spring 11 for pressing the ball 4 in a positive direction. A cylindrical member 22 is also kept at the central position through cooperation with the ball 4 and forms an annular fluid passage 25 having a proper clearance between its outer surface and a valve seat. Further, an auxiliary spring 23 acts against said means for pressing the ball 4 in the positive direction and keeps the cylindrical member 22 always in contact with the ball 4, following up the movement of the ball 4. |
