| 摘要 |
PURPOSE:To prevent a valve body-side seat from being strongly fitted internally to a valve cage-side seat and easily open a valve, by both mounting the valve cage-side seat slidably to a valve cage and providing an annular elastic member to both end sides of the seat. CONSTITUTION:Inside diameter of an annular hard material-valve cage-side seat 1 is formed larger from one end side to the other end side axially in the center P1. Here at valve closing, even if fluid pressure is applied from a lager internal contour side of the valve cage seat 1 to move a valve body 5, a valve body side seat 4 simultaneously moves to the same direction as the valve body 5 while compressing an elastic member 8a in a smaller internal contour side, then the both seats 1, 4 are never excessively internally fitted. While reversely at valve closing, even if fluid pressure is applied to the smaller internal contour side of the valve cage-side seat 1 to move the valve body 5, the valve cage side seat 1 simultaneously moves by the fluid pressure to the same direction as the valve body 5 while compressing an elastic member 8b at a larger internal contour side, then sealing quality can be maintained. |
