| 摘要 |
<p>The piston (1) is mounted in a sleeve and works with a pin and button. It is held at rest by a return spring (4). It is an external hollow cylinder (5) with several parts (6) going through it transversely and coming out near a hole in it. The cylinder and parts are in metal or alloy with a lining. The material has a specific gravity equal to or less than 7. The piston is light to make its movement easy and to use a less powerful return spring. The metals can be aluminium alloys, titanium, or duralumin.</p> |
