Dynamic characteristics of the face gear transmission system based on a rotor-shaft-bearing model with multiple nodes

Abstract

A multi-node dynamic model is proposed for the gear system composed of face gear meshing, rigid gear rotors, flexible shafts and deformable bearings, and the model is applied to investigate the characteristics of the system. Firstly, as the existing vector formula of angular velocity ignores the torsional deformation, a new formula including torsion, bending and translation is derived, and accordingly the motion equations of rotors and beam elements are formulated. The gyroscopic effect is considered in the gear rotors and shaft beams. Then, the node equation of face gear meshing is derived according to the characteristics of face gear drives, in which the gear backlash, meshing damping, time-varying mesh stiffness and transmission error excitation is involved. Finally, the dynamic model of the face geared rotor-shaft-bearing system is established with nodes assembled. The natural characteristics and the dynamic responses are investigated. Moreover, the proposed model is compared with the lumped parameter model and applied to explore the dynamic responses to variable support stiffness and support spans. Results indicate that the parameters of input shaft have enormous influence on dynamic responses rather than that of output shaft, and the influence mainly comes from the support close to meshing.