| 摘要 |
PURPOSE:To prevent a valve head from hitting a valve seat even when a reverse pressure is applied and a fluid pressure is reduced, by constituting so that a predetermined clearance is formed between the valve head of a piston and the valve seat of an outlet port under no load condition. CONSTITUTION:A piston spring 15 is fitted between a valve main body 1 and a piston 6, and the force which the piston spring 15 pushes the piston 6 upward is made such a magnitude that a clearance delta' is formed between a valve head 7 and a valve seat 4 under no load condition in which no fluid pressure is applied. Accordingly, when the fluid flows into a cylinder chamber 2 through an inlet pipe 3, the piston 6 is drawn toward an outlet pipe 5 side and the valve head 7 gets into close contact with the valve seat 4, but when a reverse pressure is applied from the outlet pipe 5, the piston 6 is balanced in the condition shown in the figure and the valve head 7 will never collide with the valve seat 4. |
