| 摘要 |
PURPOSE:To prevent a large quantity of gas from flowing out due to the damage or the like of a pipe and accessories, by providing a vertically movable cylinder which is fitted with a top plate and located in a passage in the face of the gas container side of a valve seat. CONSTITUTION:When the pressure of gas sharply rises due to an abnormality, the pressure difference between the top and bottom of a valve seat 3 drastically becomes large. Consequently, a vertically movable cylinder 7 is pushed up by the gas pressure and a lower valve 12 is closed on the bottom of the valve seat 3 to prevent the gas from flowing out through an outlet port 6. If the gas pressure is higher than a safety level, the gas is released through a safety valve 4. In order to reset the vertically movable cylinder 7 after removing the cause of the abnormality, a handle 1 is operated to push down an upper valve 2. |
