In 1000, the Book of Secrets by Ibn Khalaf al-Muradi in Islamic Spain described the use of an elevator-like lifting device to raise a large battering ram to destroy a fortress. Each elevator could carry about 600 pounds (270 kg) (roughly the weight of two lions) 23 feet (7.0 m) up when powered by up to eight men. The Roman Colosseum, completed in AD 80, had roughly 25 elevators that were used for raising animals up to the floor. Sources from later periods mention elevators as cabs on a hemp rope, powered by people or animals. 212 BC) built his first elevator probably in 236 BC. The earliest known reference to an elevator is in the works of the Roman architect Vitruvius, who reported that Archimedes (c. History Pre-industrial era Įlevator design by the German engineer Konrad Kyeser (1405) 11.1.1 Methods of removing condensed water.9.14 Material handling belts and belt elevators.9.8 Limited use and limited application.6.8 Medical emergency or code-blue service.Some elevators can also travel horizontally in addition to the usual vertical motion. Due to wheelchair access laws, elevators are often a legal requirement in new multistory buildings, especially where wheelchair ramps are not possible. Languages other than English, such as Japanese, may refer to elevators by loanwords based on either elevator or lift. Several types exist, such as the chain and bucket elevator, grain auger screw conveyor using the principle of Archimedes' screw, or the chain and paddles or forks of hay elevators. In agriculture and manufacturing, an elevator is any type of conveyor device used to lift materials in a continuous stream into bins or silos. They are typically powered by electric motors that drive traction cables and counterweight systems such as a hoist, although some pump hydraulic fluid to raise a cylindrical piston like a jack. An elevator or lift is a cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or decks of a building, vessel, or other structure.
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