Impact of residual stress on the time-varying meshing stiffness of helical gears and its dynamic analysis

ObjectiveAs an important strengthening process for gears, the quenching heat treatment will generate relatively high residual stress, which will further affect the meshing stiffness and dynamic performance of gears. Based on the analysis of the distribution law of quenching residual stress, the quantitative impact of residual stress on the meshing dynamic characteristics of gears was revealed.MethodsA gear quenching simulation model was established based on the direct thermo-mechanical coupling method to solve the quenching residual stress. Combined with the single node method, this residual stress was regarded as the prestress to solve the time-varying meshing stiffness of the helical gear pair. Based on this, the lumped parameter method was used to establish a 10-degree-of-freedom dynamic model of the helical gear pair. The Runge-Kutta method was used for numerical solution, and the time domain diagram and frequency domain diagram of the dynamic load during the vibration response of the helical gear pair were obtained.ResultsCompared with the situation without considering the residual stress, the bending deformation of a single tooth becomes larger in the four-tooth meshing area and smaller in the five-tooth meshing area. The contact deformation does not change much, and the time domain peak values of meshing stiffness and dynamic load become larger, the dynamic load frequency domain amplitude spectral density at the meshing frequency increases.