PURPOSE: To quickly balance the pressure in the occurrence of trouble by providing a controlled valve whose fluid flow rate is adjustable by an instruction, providing at least one butterfly valve on the surface of the controlled valve, and providing a device for limiting the pressure difference in order to balance the pressure when the pressure difference between both sides of the butterfly valve exceeds a limit value.
CONSTITUTION: The flow rate of a fluid passing a controlled valve 1 is related to the pressure difference between both sides of the controlled valve 1 and the surface opened by the controlled valve 1. A butterfly valve 2 is independently opened when the pressure difference between both the sides is larger than a limit value. The butterfly valve 2 is returned to the close position by two springs when the difference is smaller than the limit value of opening. The butterfly valve 2 is pivoted around a shaft 7. A motor 6 advances a rack with a rubber disc 9 according to an instruction, and the rubber disc 9 presses a flap 2' to close it. The rubber disc 9 seals the bulkhead of the butterfly valve 2. The rack can extend a rod 8 as long as the safety is to be maximized, and reaches the position of a bolt 11 in close position.
BURUNO BARUU
JIYAAKU FUREESU
JIYAAKU SHINIYORE
| JP54077350B1 | ||||
| JPS382220B1 | ||||
| JPS63159145A | 1988-07-02 |