Self-sealing lifting device

摘要

A self-locking lifting mechanism comprises an at least part-circular disc which in use is connected by an eye or shackle to a lifting device for lifting the mechanism. The disc has guide means such as a curved slot, while a pair of links is pivotally carried by the disc, the pivot also being slidable along the guide slot. A block with a slot for gripping stock to be lifted is carried pivotally by the links at their end remote from the guide slot, while a second such block is pivoted on the disc at a spacing from the guide slot. Movement of the links along the guide slot moves the first block towards or away from the second block, and lifting of the disc by means of the eye or shackle causes the disc to pivot, thereby to cause the links to move along the guide slot to grip the stock.