The reducer plays the role of matching speed and transmitting torque between the prime mover and the working machine or actuator. It is a relatively precise machine. The purpose of using it is to reduce the speed and increase the torque. It comes in many types, with different models, and different types have different uses. There are many types of reducers. According to the transmission type, they can be divided into gear reducers, worm reducers and planetary gear reducers; according to the number of transmission stages, they can be divided into single-stage and multi-stage reducers; according to the gear shape, they can be divided into cylindrical gear reduction reducer, bevel gear reducer and bevel-cylindrical gear reducer; according to the transmission layout, it can be divided into expansion reducer, split flow reducer and coaxial reducer.