| 摘要 |
Interposed between the driving shaft of the tackle and the hoisting hook of the tackle is a flat textile strap or a flat metal braid. The strap or braid is attached to the drum of a drum-pulley keyed on the driving shaft at the end of the strap or braid. The strap passes around the pulleys of a pulley-block comprising an upper block mounted on the frame of the tackle to pivot about a horizontal axis X-X, and a lower block suspended from the strap or braid and carrying the hook.
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