| 摘要 |
PROBLEM TO BE SOLVED: To provide an excessive outflow prevention valve in which a ball valve movable in a direction to shut a valve seat port in a gas flow path is easily and firmly mounted, its fixed position can be finely adjusted, and it is separable.SOLUTION: In an excessive outflow prevention valve, a holding member comprises: a fixed body 13 having a plurality of pressing parts 131, 133, and 134 radially and elastically pressing an inner peripheral surface of a gas flow path; and a holding piece 12 which protrudes toward a downstream side from a predetermined place of the fixed body 13 corresponding to the center of the gas flow path, and which separably holds a ball valve 10 at the tip thereof. First and second engaging parts 16 and 14 are formed to engage both ends of a tension spring 17 with the ball valve 10 and the holding piece 12, respectively. A natural length of the tension spring 17 is set to be shorter than a distance between the first and second engaging parts 16 and 14 in a normal state in which the ball valve 10 is held by the holding piece 12. |
