Gear is a wide range of applications, and a particularly important form of mechanical transmission, which can be used for any axis in space to pass between the movement and power, is currently gearing gradually to small, high-speed, low noise, high reliability Hardened technical direction and development of stable and reliable gear with the transmission, high transmission efficiency (typically up to 94% and high precision cylindrical gear up to 99%), transmission power range (from the meter gear small power transmission to large machinery and tens of thousands of kilowatts of power transmission) speed range (speed of the circumference of gear from 0.1m / s to 200m / s or higher, the rotational speed or higher from 1r/min to 20000r/min ), compact, and easy maintenance. Therefore, it is in a variety of mechanical equipment and instrumentation is widely used. This is a typical design of a cylindrical gear reducer gear. One small gear material 40Cr (quenched), the hardness is about 240HBS, gear material is 45 steel (quenched and tempered), hardness of about 215HBS, gear
accuracy grade 8 level. Shafts, bearings, keys are made of steel material.