| 摘要 |
<p>The screwed bottle plug has a screwed stem (1) with a widened cone portion (4) at the end and passing through a sheath (6), which slides on it. A button (13) screwed onto the threaded portion (2) of the stem acts against a flange (7) on the sheath, while a bush (18) of elastic material fits over the sheath and has an internal collar (20) fitting between the sheath end and the cone. Thus when the button is screwed down, the bush is caused to expand over the latter portion, which can be convexly curved.</p> |
