| 摘要 |
PURPOSE:To obtain a pressure controller which functions as a direct-acting pressure controller even when the primary pressure is reduced less than a prescribed level, by adding a pilot governor. CONSTITUTION:An actuator 4 containing a diaphragm 3 and a spring 5 which energizes a main valve 1 toward its closing direction is attached to a stem 2 connected directly to the valve 1. A driving pressure feeding pipe 8 of a pilot governor 7 with which the driving pressure increases and decreases in response to the change of the secondary pressure is connected to a chamber 6a at one side of the part 4. Then a feed pipe 11 containing a valve 10 that can freely switch the secondary pressure between the feed and stop states is provided to an operation mechanism 9 that can release the energizing force of the spring 5 and a chamber 6b at the other side of the part 4. As a result, a pressure controller is obtained as a direct-acting pressure controller even when the primary pressure is reduced less than a prescribed level. |
