The overall error is treated as a discrete point on the contact line of the helical gear to indicate the position and size of the error. The time-varying meshing stiffness including the influence of tooth surface friction is considered in the construction of the dynamic equation to further accurately characterize the dynamic characteristics of the helical gear.
Considering the overall error and tooth surface friction, the dynamic equation of gear transmission and the nonlinear dynamic model of gear pair are established. The dynamic equation is as follows:
Where:
TE – gear transmission error（ μ m )；
EI — overall error of gear meshing point I（ μ m )。
The driving and driven gears adopt 5-level accuracy. The gear meshing contact is regarded as point contact, and the contact line is discretized into point contact. The overall error EI of the meshing points is calculated by using the formula. The overall error curve of the gear arranged according to the actual meshing sequence of each point on the contact line is shown in the figure:
