| 摘要 |
<p>The safety bolt (1) has a flat head (1a) at one of its ends. This head cross through holes in two plates (2, 3). The other end of the bolt is formed into an eyelet (1b). On the other head (1a) of the bolt is a relatively rigid plastic material maintaining ring (4). This ring (4) has an internal stop (4a) which is shaped to form a ramp (4b) over which the flat head (1a) of the bolt will pass if it is pulled.</p> |
