| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce replacement cost of a gas plug by replacing a valve unit with another new valve unit. <P>SOLUTION: In this gas plug, a casing 7 is extractably inserted in a gas outflow hole 1b of a plug body 1. On a casing 7, a through-hole 7a communicating with a gas inflow hole 1a by penetrating its circumferential wall part is formed, and a gas is made to flow in the casing 7. Thereby, the inside of the casing 7 is used for an upstream-side outflow hole 7b being a part of the gas outflow hole 1b. In the upstream-side outflow hole 7b, first and second coil springs 4A and 4B, a main valve 3, a third coil spring 5 and an auxiliary valve 3 are inserted in a coming-off prevention state. Thereby, a valve unit 6 is formed. When the inside surface of the upstream-side outflow hole 7b is damaged by the main valve 2, the valve unit 6 is replaced with another new valve unit 6. The plug body 1 is reused. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
