| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an air valve which is increased in blocking capability against the intrusion of rain water or the like from the outside and simple in structure. <P>SOLUTION: The air valve 1 comprises: a valve box 2 having a ventilation port 2a at its upper end, a water-passing port 2b at its lower end, a hollow part 2c in the lower part of the ventilation port 2a, and a water introduction part 2d in the lower part of the hollow part; an inner lid body 3 having a large air hole 3a and attached to the ventilation port 2a of the valve box 2; an outer lid body 4 arranged so as to cover the upper part of the large air hole 3a; a valve body guide 5 arranged in the hollow part 2c; a float valve body 6; and an idle valve body 7 which has a small air hole 7a vertically penetrating the body and whose upper end face can block the large air hole 3a of the inner lid body 3. The air valve further comprises a plug body 8 which has an internal hollow part 8a attached between the inner lid body 3 and the outer lid body 4, capable of blocking the large air hole 3a and communicating with the small air hole 7a in a state of blocking the large air hole 3a, and a second small air hole 8b penetrating the wall 80a of the plug body, and in which there is arranged a ring-shaped elastic body 81 which closely contacts with the external face of the wall 80 by a prescribed elastic force and can block the second air hole 8b. <P>COPYRIGHT: (C)2013,JPO&INPIT |
