| 摘要 |
<p>The retraction control is for a lifting jib access platform (10) which has a chassis (11) and a load carrier (17). The jib (18) is telescopic and is pivoted relative to the chassis on a horizontal axis (20). When the jib is lowered, it is simultaneously withdrawn automatically, proportional to the lowering speed of the jib. The drive has two double-acting actuators to give the required action. A fluid circuit feeds exhaust fluid from one large capacity actuator (21) lowering the jib to another actuator (32) withdrawing it.</p> |
