摘要 |
A stopper for a tank having an opening includes a body which is provided to be fixed in the opening and which has a hole, a membrane which is fixed to the body and of which a portion completely blocks the hole, a core which is fixed to the portion of the membrane which blocks the hole, and stop means which are provided to permit a movement of the core between a blocking position which corresponds to the non-broken membrane which blocks the hole, and an open position which corresponds to the broken membrane which is spaced apart from the hole, and to keep the core fixedly joined to the body in an open position. The knowledge of the characteristics of the membrane enables the force from which the stopper opens to be known. |