| 摘要 |
PURPOSE:To automatically and always reliably engage and disengage a lift-up, by a method wherein a hook device comprising a pair of hooks, a cam for opening and closing a hook, a follower, and a rod for operating the cam, and a claw part, located to the lower end of each of the two hooks, and a stopper are provided. CONSTITUTION:A hook device 24 is constituted such that two claw parts 26A and 27A are spaced away from each other, and the two claw parts 26a and 27A are positioned below a hung part 23. Hooks 26 and 27 are released from the restraint force of cam actuating plates 26B and 27B, and the two claw parts 26A and 27A are automatically approached to each other under gravity for closing. When a lift beam pulley box 16 is lowered, a lifting beam 12 is received by a stopper 34, and the two hooks 26 and 27 are rotated to disengage them from each other. This enables the hook, released from a restrain force, to be automatically rocked so that the claw parts are engaged with a part to be lifted. |
