| 摘要 |
<p>M shaped profiles (1) are nested together, contact between them being by wing pieces (9). There is a locking part, consisting of a collar (3), and at the bottom of the M section is welded another part (4) of similar profile. Locking is effected by the shank of a bolt (5) which goes through two holes (6) in the collar near its ends. The bolt shank forms the shaft for a double locking cam, of two pieces (7a, 7b) forming a type of bobbin. The two cams lock at a point (10) to press the profiles (1, 2) together. Two forms of locking are given, one by friction between surfaces of the profile and another by cam.</p> |
