| 摘要 |
<p>The present invention relates to an automatic closing-opening device for plastic gas branch pipeline mounted into the end-section of the branch pipe which is joined to the plastic gas-distribution pipe-line. The closing-opening device has a metallic closing member (5) pressed in suitable distance from the gas-distribution pipe (3) into a piece of pipe (2), said closing member (5) having in its centre a bore (8) concentrically with said branch pipe (1), said closing member (5) further having a cone-shaped outer mantle surface (7), said device further having in the direction of the gas flow in front of said closing member (5) a pinlike member (10) fixed in said piece of pipe (2) practically at right angle to the axis of said branch pipe (1), said device further having a ball (11) with a diameter greater than that of said bore (8) of said closing member (5), said ball (11) can move freely in the space between said closing member (5) and said pinlike member (10).</p> |
