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Hoist atop an elevator. A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium.
A trapdoor or hatch is a sliding or hinged door that is flush with the surface of a floor, ceiling, or roof. [1] It is traditionally small in size. [ 2 ] It was invented to facilitate the hoisting of grain up through mills, however, its list of uses has grown over time. [ 3 ]
The slab lifter uses two safety devices. Safety chains and a support bracket allow safe lifting of large slabs. This lifting appliance also has a safety locking device that is engaged when the gripping pads are activated by the weight of the stone. This prevents any jerking movement from releasing the stone.
The Roman Polyspaston crane, from Ancient Greek πολύσπαστον (polúspaston, “compound pulley”), when worked by four men at both sides of the winch, could lift 3000 kg. In case the winch was replaced by a treadwheel, the maximum load even doubled to 6000 kg at only half the crew, since the treadwheel possesses a much bigger ...
The New York roof hook (or halligan hook) is a firefighting tool used mostly for rooftop operations including vertical and horizontal ventilation, [1] pulling and prying. Developed in the 1940s by FDNY Deputy Chief Hugh Halligan, a prolific firefighting inventor who also designed the Halligan bar , the tool is composed of a 6-foot (1.8 m) long ...
The first type of crane machine was the shadouf, which had a lever mechanism and was used to lift water for irrigation. [ 3 ] [ 4 ] [ 5 ] It was invented in Mesopotamia (modern Iraq) circa 3000 BC. [ 3 ] [ 4 ] The shadouf subsequently appeared in ancient Egyptian technology circa 2000 BC.
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A demonstration of using two stacked air bags to lift the rear of a car. An inflatable jack, lifting bag, or pneumatic lifting bag is an air bag that is inflated by compressed air (without a hydraulic component) in order to lift objects. The bag can be deflated to be reused later.