| 摘要 |
PROBLEM TO BE SOLVED: To provide a valve device with excess flow check function capable of miniaturizing an excess flow check valve and minimizing pressure loss of a main passage.SOLUTION: A valve device 1 includes an aperture 24, a main valve 12 and an excess flow check valve 14. The aperture 24 and the main valve 12 are respectively interposed into a pilot passage 23 and a main passage 28 which are respectively connected to a tank 2. The main valve 12 closes the main passage 28 when a pilot pressure pof the pilot passage 23 increases and a differential pressure between the pilot pressure pand a primary pressure pdecreases. Further, the downstream side from the aperture 24 of the pilot passage 23 and the downstream side from the main valve 12 of the main passage 28 are linked by a bypass passage 41, and the excess flow check valve 14 is interposed on the bypass passage 41. When the flow rate of fluid flowing through the bypass passage 41 becomes a predetermined value or more, the excess flow check valve 14 closes the bypass passage 41 and increases the pilot pressure. |
