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Geared machines use worm gears to control mechanical movement of elevator cars by "rolling" steel hoist ropes over a drive sheave which is attached to a gearbox driven by a high-speed motor. These machines are generally the best option for basement or overhead traction use for speeds up to 3 m/s (500 ft/min). [51]
A crane is a machine used to move materials both vertically and horizontally, utilizing a system of a boom, hoist, wire ropes or chains, and sheaves for lifting and relocating heavy objects within the swing of its boom. The device uses one or more simple machines, such as the lever and pulley, to create mechanical advantage to do its work.
A simple machine is a mechanical device that changes the direction or magnitude of a force. [1] In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. [2] Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: [3] [4 ...
The hand axe is the first example of a wedge, the oldest of the six classic simple machines, from which most machines are based. The second oldest simple machine was the inclined plane (ramp), [6] which has been used since prehistoric times to move heavy objects. [7] [8] The other four simple machines were invented in the ancient Near East. [9]
Simple machine – There are only 3 fundamental machines, with 4 variations, for a total of 7 simple machines Lever; Inclined Plane. Screw – combination of a wheel and an inclined plane; Wedge; Wheel. Pulley; Gear – combination of a wheel and a lever; Vehicles. Man powered vehicles Bicycle; Pedalo; Powered vehicles Car; Train; Airplane ...
The wheel and axle is a simple machine, consisting of a wheel attached to a smaller axle so that these two parts rotate together, in which a force is transferred from one to the other. The wheel and axle can be viewed as a version of the Lever , with a drive force applied tangentially to the perimeter of the wheel, and a load force applied to ...
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Human-powered transport is the transport of person(s) and/or goods using human muscle power.Unlike animal-powered transport, human-powered transport has existed since time immemorial in the form of walking, running and swimming, as well as small vehicles such as litters, rickshaws, wheelchairs and wheelbarrows.