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Development history of gears

 03-02


As early as 350 BC, the famous Greek philosopher Aristotle had recorded gears in the literature. Around 250 BC, mathematician Archimedes also described hoisting machines using turbines and worms in the literature. BC gears are still preserved in the ruins of Katersfin in Iraq today.



Plastic gear


Gear has a long history in China. According to historical records, gears have been used in ancient China as far back as 400 ~ 200 BC. The bronze gears unearthed in Shanxi in China are ancient gears that have been discovered so far. As a guide to reflect the achievements of ancient science and technology, the gear mechanism is the The core mechanism. During the Italian Renaissance in the second half of the 15th century, the well-known generalist Leonardo Da Vinci left an indelible feat not only in culture and art, but also in the history of gear technology. After more than 500 years, the current The gear still retains the original sketch of the time.


Plastic gear


It was not until the end of the 17th century that people began to study the shape of the gear teeth that can correctly transfer motion. In the 18th century, after the European Industrial Revolution, the application of gear transmission became more and more extensive; first, the development of cycloid gears, and then involute gears, until the beginning of the 20th century, involute gears had dominated applications. Later, shift gears, arc gears, bevel gears, helical gears, etc. were developed.


Plastic gear


Modern gear technology has reached: gear module 0.004-100mm; gear diameter from 1mm-150m; transmission power up to 100,000 kilowatts; speed up to 100,000 rpm; peripheral speed up to 300m / s.

Internationally, power transmission gear devices are developing in the direction of miniaturization, high speed, and standardization. The application of special gears, the development of planetary gear devices, and the development of low-vibration and low-noise gear devices are some of the characteristics of gear design.

 




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