The bend-torsional coupling nonlinear dynamics model of power split transmissions of face gear is established.The time-varying mesh stiffness

mesh phase

meshing error and tooth backlash are included in the model.Based on the numerical solutions

the dynamic load factor and the phase diagram

Poincare map

FFT diagram of the dynamic response are analyzed.The results show that the dynamic load level of each path is different

and quasi-periodic responses

chaos responses can be obtained at different revolving speeds.Then

the dynamic load factor and the phase diagram of the dynamic response are analyzed for different tooth backlash

the results show that the dynamic characteristic will not change with the variation of tooth backlash when the value of tooth backlash is greater than a certain critical value.