| 摘要 |
<p>The lock (1), particularly for uprights of metal door frames, comprises a boxlike body or casing (2) associable with a front plate (3), and having a bolt (4) inside it, the bolt (4) is operated by a cylinder through a kinematic means (5), the cylinder is operated by a key, a moving means (6) for moving the rotational fulcrum (14) of the bolt (4) from at least a first position to a second position for preventing the return of the bolt (4) into the casing (2) when the bolt (4) is subjected to an undesired return force to make it return into the casing (2). <IMAGE></p> |
