| 摘要 |
PROBLEM TO BE SOLVED: To provide an air valve capable of preventing damages of a float and a guide frame body even when the air valve suffers strong quake such as an earthquake.SOLUTION: In an air valve 6 configured so that an air hole 14 is formed on an upper part of a valve box 8, a communication hole 17 communicated to a conduit line is formed on a lower part of the valve box 8, a floating valve body 9 for opening/closing the air hole 14, a float 10 for moving the floating valve body 9 in an opening/closing direction and a guide frame body 11 for guiding the floating valve body 9 and the float 10 in the opening/closing direction are stored in the valve box 8, an upper part in the guide frame body 11 is opened and communicated to the air hole 14, an intra-valve box passage 24 communicated to the communication hole 17 is formed between an inner peripheral surface of the valve box 8 and an outer peripheral surface of the guide frame body 11, and the intra-valve box passage 24 and the air hole 14 are communicated to each other through a circulation port 22 of the guide frame body 11, a narrow part 26 narrowing a cross section of the intra-valve box passage 24 is formed in the valve box 8. |
