| 摘要 |
PURPOSE:To permit an emergency shut-off valve to be inoperative in any accidental abnormal flow speed and shut off a flow path in an emergency only at actually necessary time by constituting said valve to detect the continuation of abnormal flow speed condition. CONSTITUTION:A valve closing mechanism 12 is so arranged as to mount a weight 20 on the one end side while mounting on the other end side an arm 23 provided with a container 21 and set swingably about a transverse shaft so that a lock mechanism 10 may be maintained under the operative condition by the energizing action of the weight 20. And a flow path 24 provided with a pump P for supplying liquid reserved in a second container 22 to the first container 21 under the open atmospheric condition is installed while a downcast path 25 for discharging liquid reserved in the first container 21 to the second container 22 by its natural downcasting is also installed in the first container 21, and a variable throttle valve V is provided in the downcast path 25. The pump P is driven by a drive mechanism 28. The continuity of abnormal flow speed condition can be detected on the basis of liquid storage more than the predetermined amount in said container 21. |
