| 摘要 |
<p>PURPOSE:To prevent air leakage when a plug is mounted or removed, and simplify the mounting/removing structure. CONSTITUTION:At the tip of an outer cylinder 10, an insertion part 14 is provided where a plug is inserted, and a seal member 20 is mounted on the inner surface of this insertion part 14. A cylindrical seal piston 40 is installed in the outer cylinder 10, and the gap between inside of the insertion part and the space behind it is sealed by pressing the seal piston 40 toward the foremost by a compressive spring 50. A pluger pin 70 is installed in the seal piston 40 in such a way as not movable in the axial direction. Before the plunger of the plug is pressed by the plunger pin 70, the seal piston 40 retreats, and inside of the insertion part 14 is put in communication with the space behind.</p> |
