Shaft Coupling

China gear industry in the "Tenth Five-Year" period has been the rapid development of: gear industry in 2005 by the annual production value of 24 billion yuan in 2000 to 68.3 billion yuan, the annual compound growth rate of 23.27 percent, China has become pieces of machinery based on the largest industry. On market demand and production capacity, China gear industry in the world for more than Italy, ranking fourth in the world.
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According to historical records, far from 400 BC to 200 years in ancient China has been started on the use of gears, unearthed in Shanxi Province in China's bronze gear have been found so far the oldest of the gear, as reflected in scientific and technological achievements of ancient cart is gearing mechanical devices at the core. End of the 17th century, people began to study transmission of movement to correct the shape of the tooth. The 18th century, the European industrial revolution, the gear drives the application of the increasingly widespread; first cycloid gear development, and the latter is the involute gear until the early 20th century, involute gear has been accounted for in the application of the advantage.
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