Planetary gear reducer is also known as planetary reducer, servo reducer. In the reducer family, the planetary reducer is widely used in the servo motor, stepping motor, dc motor and other drive systems because of its small size, high transmission efficiency, wide reduction range, high accuracy and many other advantages. Its function is in the premise of ensuring precision transmission, mainly used to reduce the rotation speed and increase torque and reduce the load/motor rotational inertia ratio.

The main transmission structure of planetary gear reducer is: planetary wheel, solar wheel, inner gear ring.

Due to structural reasons, the single-stage deceleration is at least 3, and the maximum is generally less than 10. The common deceleration ratio is: 3/4/5/6/8/10. The reduction series of the reducer is generally less than 3, but some of the large deceleration has 4 stages of deceleration compared with the customized reducer. Compared with other reducer, planetary reducer has the characteristics of high rigidity, high precision (single stage can achieve less than 1 point), high transmission efficiency (single stage in 97-98%), high torque/volume ratio, life maintenance free. Because of these characteristics, planetary speed reducer is mostly installed in the stepper motor and servo motor, used to reduce the speed, improve the torque, matching inertia. The highest rated input speed of planetary reducer can reach 18000rpm(related to the size of the reducer itself, the larger the reducer, the smaller the rated input speed) above, the working temperature is generally from -25℃ to about 100℃, and its working temperature can be changed by changing the grease.

Precision planetary reducer with servo motor so the backclearance level (arc minute) is very important, different backclearance level price difference is quite big, planetary reducer can do multiple gear box connection up to 100,000 maximum reduction ratio.