| 摘要 |
<p>A locking mechanism for two sections of a sliding frame forming a mast such as a crane mast, has a tube (3) mounted on one section (12) with two compartments inside divided by a partition (4) housing springs (8) acting against a locking spindle (7). This spindle has a pivot pin (9) passing through it, carrying a ball bearing mounted disc (12) one end. This disc locates inside the V shaped end of a latch arm (16) mounted on a pivot pin (15) at the outermost end of the tube (3). When one mast section is lifted, the ball bearing disc is forced back against spring pressure, releasing the latch arm and allowing it disengage from a stop (29) by swinging about its pivot (15). At the same time the locking spindle (7) enters a locating bush (30) and locks the mast section.</p> |
