| 摘要 |
Abstract of the Disclosure A hoist pivotally connecting mast 1 to lifting arm 2, by a mechanism comprising a link 5 pivoting about a fixed pivot 8 on the mast 1 and a moving pivot 6 on the lifting arm 2. A restraining link 9 between a pivot 10 on the mast 1 and actuator attachment point 11 on the lifting arm 2 restricts the movement of link 5. The second link 9 acts as a stabilizer allowing the pivot 11 on the lifting arm 2 to move only through a set arc, determined by the length of the link 9 and the position of the pivot 10 on the mast 1. With the moving pivot according to the invention, the spreader bar attachment point 7 has a greater traveling distance than if it were simply pivoted about pivot 8 as with conventional hoists.
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