摘要 |
The fixed frame (11',11'') of the hinge mechanism (10) has bearing loops at the top and bottom. There are four equispaced vertical grooves inside the top and bottom loops. The middle portion of the pin fits inside a sleeve (14) with a spring-loaded portion (19) at the top. The loop (15) on the movable hinge portion (12) has chamfered surfaces near its ends, which bear on chamfered surfaces on the sleeve and spring-loaded portion. |