Abstract: In order to study the dynamic characteristics of gearbox housing in high-speed train, the internal and external dynamic excitations of gear transmission system in high-speed train are calculated by numerical simulation at first, and a multi-body dynamics model of motor car including the driving system subjected to internal and external excitation is established. In this model, the internal excitations include the time-varying stiffness, damping and transmission error, the external excitations include the harmonic torque of asynchronous motor and rail irregularity, then the dynamic forces generated in the gear mesh are calculated when the train running with constant power. What is more, the dynamic forces of housing bearing seats are obtained and loaded to the finite element model of gearbox housing, the dynamic response of housing is carried out using a direct integrate method and harmonic response analysis are also finished. The results show that the high frequency vibration of the gear transmission system can only be acquired when the gear meshing is considered in the dynamics model. The gearbox housing structure design is sufficient for operation requirement. Frequency of harmonic torque and the gear mesh frequency are also appeared in the dynamic response of gearbox housing. During the structure design of gearbox, it should pay attention that the gearbox mode natural frequencies need to avoid the meshing frequency and external excitation frequency, so as to prevent the resonance.

Key words: gear meshing, dynamic response, gearbox, resonance, high-speed train