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Drive Pulley
file:Trissa linhjul utan rep sheave pulley wheel without rope.png, Sheave without a rope A pulley is a wheel on an axle or shaft (mechanical engineering), shaft enabling a taut cable or Belt (mechanical), belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A pulley may have a Groove (machining), 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, Wire rope, cable, belt, or chain. History The earliest evidence of pulleys dates back to Ancient Egypt in the Twelfth Dynasty of Egypt, Twelfth Dynasty (1991–1802 BC) and Mesopotamia in the early 2nd millennium BC. In Roman Egypt, Hero of Alexandria (c. 10–70 AD) identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt (me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block (sailing)
In sailing, a block is a single or multiple pulley. One or a number of '' sheaves'' are enclosed in an assembly between ''cheeks'' or ''chocks''. In use, a block is fixed to the end of a line, to a spar, or to a surface. A line (rope) is ''reeved'' through the sheaves, and maybe through one or more matching blocks at some far end, to make up a tackle. The ''purchase'' of a tackle refers to its mechanical advantage. In general the more sheaves in the blocks that make up a tackle, the higher its mechanical advantage. The matter is slightly complicated by the fact that every tackle has a ''working end'' where the final run of rope leaves the last sheave. More mechanical advantage can be obtained if this end is attached to the moving load rather than the fixed end of the tackle. There are various types of blocks that are used in sailing. Some blocks are used to increase mechanical advantage and others are used simply to change the direction of a line. A ''ratchet block'' turn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hero Of Alexandria
Hero of Alexandria (; , , also known as Heron of Alexandria ; probably 1st or 2nd century AD) was a Greek mathematician and engineer who was active in Alexandria in Egypt during the Roman era. He has been described as the greatest experimentalist of antiquity and a representative of the Hellenistic scientific tradition. Hero published a well-recognized description of a steam-powered device called an '' aeolipile'', also known as "Hero's engine". Among his most famous inventions was a windwheel, constituting the earliest instance of wind harnessing on land. In his work ''Mechanics'', he described pantographs. Some of his ideas were derived from the works of Ctesibius. In mathematics, he wrote a commentary on Euclid's ''Elements'' and a work on applied geometry known as the ''Metrica''. He is mostly remembered for Heron's formula; a way to calculate the area of a triangle using only the lengths of its sides. Much of Hero's original writings and designs have been lost, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simple Machine
A simple machine is a machine, mechanical device that changes the Direction (geometry) , direction or Magnitude_(mathematics) , magnitude of a force. In general, they can be defined as the simplest Mechanism (engineering) , mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: * Lever * Wheel and axle * Pulley * Inclined plane * Wedge (mechanical device), Wedge * Screw (simple machine), Screw A simple machine uses a single applied force to do Mechanical work, work against a single load force. Ignoring friction losses, the work done on the load is equal to the work done by the applied force. The machine can increase the amount of the output force, at the cost of a proportional decrease in the distance moved by the load. The ratio of the output to the applied force is called the ''mechanical advantage''. Simple machines can be regarded as the eleme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crane Pulley 4x
Crane or cranes may refer to: Common meanings * Crane (bird), a large, long-necked bird * Crane (machine), industrial machinery for lifting ** Crane (rail), a crane suited for use on railroads People and fictional characters * Crane (surname), including a list of people and fictional characters with the surname * Crane (given name), a list of people Places Barbados * The Crane, Saint Philip, Barbados United Kingdom * River Crane, Dorset * River Crane, London, a small river of London, branch to the Thames ** Crane (ward), an former electoral ward of Hillingdon London Borough Council that existed from 1978 to 2002 United States * Crane, Indiana, a town * Crane, Missouri, a town * Crane, Montana, a census-designated place and unincorporated community * Crane, Oregon, a census-designated place and unincorporated community * Crane County, Texas ** Crane, Texas, a city and the county seat * Crane, Virginia, an unincorporated community * Crane, Washington, an unincorpo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulley In Oil Well
Sheave without a rope A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. 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. History The earliest evidence of pulleys dates back to Ancient Egypt in the Twelfth Dynasty (1991–1802 BC) and Mesopotamia in the early 2nd millennium BC. In Roman Egypt, Hero of Alexandria (c. 10–70 AD) identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another. Plutarch's ''Parallel Lives'' recounts a scene where Archimedes proved the effectiveness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ideal Mechanical Advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for this is the ''law of the lever.'' Machine components designed to manage forces and movement in this way are called mechanisms. An ideal mechanism transmits power without adding to or subtracting from it. This means the ideal machine does not include a power source, is frictionless, and is constructed from rigid bodies that do not deflect or wear. The performance of a real system relative to this ideal is expressed in terms of efficiency factors that take into account departures from the ideal. Levers The lever is a movable bar that pivots on a fulcrum attached to or positioned on or across a fixed point. The lever operates by applying forces at different distances from the fulcrum, or pivot. The location of the fulcrum determi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tackles
Tackle may refer to: * In football: ** Tackle (football move), a play in various forms of football ** Tackle (gridiron football position) A tackle is a playing position in American football. Historically, in the one-platoon system prevalent in the late nineteenth and early twentieth centuries, a tackle played on both offense and defense. In the modern system of specialized unit ..., a position in American football and Canadian football ** Dump tackle, a forceful move in rugby of picking up an opposing player and throwing them to the ground ** The Tackle, a term for the final play of Super Bowl XXXIV ** Sliding tackle, a tackle in association football * Fishing tackle, the gear or equipment used when fishing * An assembly of pulleys with a rope threaded through them; see block and tackle * Tackle (Transformers), a fictional character {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archimedes
Archimedes of Syracuse ( ; ) was an Ancient Greece, Ancient Greek Greek mathematics, mathematician, physicist, engineer, astronomer, and Invention, inventor from the ancient city of Syracuse, Sicily, Syracuse in History of Greek and Hellenistic Sicily, Sicily. Although few details of his life are known, based on his surviving work, he is considered one of the leading scientists in classical antiquity, and one of the greatest mathematicians of all time. Archimedes anticipated modern calculus and mathematical analysis, analysis by applying the concept of the Cavalieri's principle, infinitesimals and the method of exhaustion to derive and rigorously prove many geometry, geometrical theorem, theorems, including the area of a circle, the surface area and volume of a sphere, the area of an ellipse, the area under a parabola, the volume of a segment of a paraboloid of revolution, the volume of a segment of a hyperboloid of revolution, and the area of a spiral. Archimedes' other math ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Lives
* Culture of ancient Greece Culture of ancient Rome Ancient Greek biographical works Ethics literature History books about ancient Rome Cultural depictions of Gaius Marius Cultural depictions of Mark Antony Cultural depictions of Cicero Depictions of Julius Caesar in literature Cultural depictions of Pompey Cultural depictions of Marcus Junius Brutus Cultural depictions of Marcus Licinius Crassus Cultural depictions of Theseus Cultural depictions of Romulus and Remus Cultural depictions of Cato the Younger Cultural depictions of Sulla Cultural depictions of Alexander the Great The ''Parallel Lives'' (, ''Bíoi Parállēloi''; ) is a series of 48 biographies of famous men written in Greek by the Greco-Roman philosopher, historian, and Apollonian priest Plutarch, probably at the beginning of the second century. The lives are arranged in pairs to illuminate their common moral virtues or failings. While any historically valuable similarities are often forced, these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutarch
Plutarch (; , ''Ploútarchos'', ; – 120s) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo (Delphi), Temple of Apollo in Delphi. He is known primarily for his ''Parallel Lives'', a series of biographies of illustrious Greeks and Romans, and ''Moralia'', a collection of essays and speeches. Upon becoming a Roman citizen, he was possibly named Lucius Mestrius Plutarchus (). Family Plutarch was born to a prominent family in the small town of Chaeronea, about east of Delphi, in the Greek region of Boeotia. His family was long established in the town; his father was named Autobulus and his grandfather was named Lamprias. His brothers, Timon and Lamprias, are frequently mentioned in his essays and dialogues, which speak of Timon in particular in the most affectionate terms. Studies and life Plutarch studied mathematics and philosophy in Athens under Ammonius of Athens, Ammonius from AD 66 to 67. He attended th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain Drive
Chain drive is a way of transmitting mechanical power from one place to another. It is often used to convey power to the wheels of a vehicle, particularly bicycles and motorcycles. It is also used in a wide variety of machines besides vehicles. Most often, the power is conveyed by a roller chain, known as the drive chain or transmission chain, passing over a sprocket, with the teeth of the gear meshing with the holes in the links of the chain. The gear is turned, and this pulls the chain putting mechanical force into the system. Another type of drive chain is the Morse chain, invented by the Morse Chain Company of Ithaca, New York, United States. This has inverted teeth. Sometimes the power is output by simply rotating the chain, which can be used to lift or drag objects. In other situations, a second gear is placed and the power is recovered by attaching shafts or hubs to this gear. Though drive chains are often simple oval loops, they can also go around corners by placing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belt (mechanical)
A belt is a loop of flexible material used to link two or more rotating shafts mechanically, most often parallel. Belts may be used as a source of motion, to transmit power efficiently or to track relative movement. Belts are looped over pulleys and may have a twist between the pulleys, and the shafts need not be parallel. In a two pulley system, the belt can either drive the pulleys normally in one direction (the same if on parallel shafts), or the belt may be crossed, so that the direction of the driven shaft is reversed (the opposite direction to the driver if on parallel shafts). The belt drive can also be used to change the speed of rotation, either up or down, by using different sized pulleys. As a source of motion, a conveyor belt is one application where the belt is adapted to carry a load continuously between two points. History The mechanical belt drive, using a pulley machine, was first mentioned in the text of the ''Dictionary of Local Expressions'' by the Han ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
