In addition to the static transmission error, time-varying meshing stiffness and other internal excitation will affect the vibration of the reducer variable speed integrated gear system, the changes of the dynamic part, load part and other parts of the gear system will also become the dynamic excitation source in the process of gear meshing. Therefore, these factors are collectively referred to as the external excitation in the process of gear meshing.

In the case of studying the influence of typical internal excitation on gear vibration, as a typical representative of external excitation, the influence of load torque on gear vibration also needs to be discussed.

When calculating the influence law of load torque on dynamic response, the set torque T2 does not change with time. When the gear is in stable running state, when the load torque increases from 0 to 200 N · m, the peak to peak PPV value of non-circular gear is shown in the figure. It can be seen from the figure that when the load torque increases, the dynamic response peak to peak value PPV is increased The value increases approximately linearly, which is the same as the circular face gear.