| 摘要 |
PURPOSE:To reduce the generation of noise, by attaining a reduction of pressure with a working mechanism that applies a working pressure to a bellows with the dynamic pressure of a fluid itself and giving a balance to the bellows so that it keep an opening appropriate to a flow. CONSTITUTION:A bellows 4 is provided at a port part to extend from a fixed end 10' and then presses with a free control the gap between the port part and a sheet part. when a working pressure having a relation of P1>P2>P3 is applied to the bellows 4, a downward force to press the port part down by the pressure P2 is applied to a pilot governor secondary room 19 through a tube 22. And a balance is obtained at a certain position between the push-up force and the push-down force. Both the balancing position and the working pressure P2 are decided by the primary side pressure P1 and the secondary side pressure P3 plus the flow rate of gas which flows at that moment. When the pressure P3 is higher than the set value, the pressure P2 becomes high to increase the force that pressed the port part down via the function of a pilot valve with which a part of the fluid works in division. |
