what is the gear

Gears are meshing with teeth can help each other mechanical parts, it is in the whole machinery and mechanical drive applications in the field is extremely broad. Modern technology has reached Gear: Gear Modulus 0.004 to 100 mm; gear diameter from 1 mm ~ 150 m; deliver power up to the one hundred thousand kilowatts; speeds up to several hundred thousand rev / min; maximum peripheral speed of 300 m / sec. With the development of production, the smooth running gear attention. Danish astronomer Roemer in 1674 first proposed for use Epicycloid tooth profile to get the smooth operation of the gears.
China gear industry rapid development, the industry is expanding. In the "Eleventh Five-Year" period, according to the National Bureau of Statistics data released Intek consulting, from 2005 to 2010 China gear industry, industrial output value increased year by year, and 18.00 percent year on year increase in more than 2009 industrial output value of 781.85 billion in 2010 industrial output value of 94.635 billion yuan. China gear industry has become the largest mechanical basic parts industry. In 2011, the gear industry sales reached 178 billion yuan total, an increase of 23%; imports, although still much higher than exports, but export growth was significantly stronger than imports. China gear companies after the test of market competition at home and abroad, as well as the global financial crisis of experience in the development of their own operational practices, already abandoned the low level of production and low-quality, low-price competition model, the entire industry is moving into a 'broken pupation butterfly 'type of a new stage of development.
Commonly used in the manufacture of gears with steel quenched and tempered steel, hardened steel, case hardening steel and nitriding steel. Slightly lower than the strength of forged steel, commonly used in sizes larger gear; poor mechanical properties of gray cast iron can be used for light load of open gear drive; ductile iron can partially replace the steel gears; multi-purpose plastic gear at light load and low noise requirements of the place, with its paired gear generally good thermal conductivity of steel gears.
Gear theory and manufacturing process development will be further studied the mechanism of tooth damage, the intensity of which is to establish a reliable basis for calculation method is to increase the carrying capacity of the gear to extend gear life theory; development of arc tooth profile as the representative of new tooth; research of new materials and manufacturing gear new technology; study the elastic deformation of the gear, manufacture and installation errors and temperature field distribution for tooth modification, in order to improve the smooth running gear and at full load increase the contact area of the tooth, thereby improving the carrying capacity of the gear.