The reasons for the noise of the reduction gear box are mainly in the following aspects:

     1. Gear design: improper parameter selection, too small overlap, improper or no modification of tooth profile, unreasonable structure of gearbox, etc.

     2. Gear processing: the base pitch error and tooth profile error are too large, the tooth side clearance is too large, the surface roughness is too large, etc.

     3. In terms of gear train and gear box: assembly eccentricity, low contact accuracy, poor parallelism of the shaft, insufficient stiffness of the shaft, bearing and support, and poor rotation accuracy of the bearing.Improper height and clearance, etc.

     4. Input torque in other aspects. Fluctuation of load torque, torsional vibration of shafting, balance of motor and other transmission pairs, etc.