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A pulley clothes airer is sometimes also described as "Victorian", "Edwardian", or "Lancashire" and then comprises two iron frames positioned as far apart as desired to provide a suitable length, with wooden laths, typically four or six, passed through holes in them. The frames are suspended from the ceiling by a system of rope and pulleys.
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.
The winch may be mounted to a vehicle, set into the ground by stakes, or tied to a tree. The cable may also be run through pulleys mounted offshore so that it pulls the person away from where the winch is located, and multiple pulleys may be used to multiply the force applied by a small but high revving motor instead of using a transmission.
Vitruvius, a military engineer writing about 28 BC, defined a machine as "a combination of timber fastened together, chiefly efficacious in moving great weights."About a century later, Hero of Alexandria summarized the practice of his day by naming the "five simple machines" for "moving a given weight by a given force" as the lever, windlass, screw for power, wedge, and tackle block (pulley).
In the attic, a man was turning a crank to power the device. [15] [16] [17] In 1827, Sir William Congreve, 2nd Baronet devised a machine running on capillary action [8] that would disobey the principle that water seeks its own level, so to produce a continuous ascent and overflow. The device had an inclined plane over pulleys. [8]
A sheave or pulley wheel is a pulley using an axle supported by a frame or shell (block) to guide a cable or exert force. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt. The drive element of a pulley system can be a rope, cable, belt, or chain.
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A rigger or slinger is a skilled tradesperson who specializes in the assistance of manual mechanical advantage device comprising pulley, block and tackle or motorised such as a crane or derrick or chain hoists (chain fall) or capstan winch.