| 摘要 |
<p>A pelican hook employs two locks for locking the hook arm in its closed position against the main body of the hook. One lock consists of a retractable spring-loaded locking pin which extends obliquely through the main body and into a passage in the arm when the arm is in its closed position. The other lock is a spring-loaded retractable sleeve slidably mounted on the main body. The sleeve is biased to a reference position on the main body wherein it encircles the free end of the arm when the arm is in its closed position and is retractable to a position beyond the arm end. In order to open the hook, both locks must be retracted in different directions simultaneously.</p> |
