| 摘要 |
<p>The safety catch is for cable (2) operated lifting gear for a vertically moving platform (6) held by a cable and guided by columns (3). There are hinged pawls (25) on the platform worked by flexible parts to work with racks (7). These lift from the rack teeth when the platform is raised. Each pawl is connected to a pneumatic ram (30). When the rams are pressurised, the pawls are disengaged from the racks. The rams are in a circuit which can deliver air to them and exhaust it from them. A tension sensor (9) empties air automatically if it detects abnormal cable tension.</p> |
