Modeling and vibration feature analysis of a spur gear-bearing system with a misaligned shaft angle

A gear-bearing dynamic model is presented to investigate the vibration features of the system with a misaligned shaft angle. The time-varying mesh stiffness (TVMS), time-varying pressure angle and eccentricity are considered in the model. In addition, a new expression of the load distribution function of the tooth is proposed to obtain accurate effects of the misaligned shaft angle on the TVMS. Based on the proposed model, the vibration of the system and the TVMS are solved jointly. This model is solved by the fourth-order Runge–Kutta, and the TVMS is calculated by the energy potential method where one mesh stiffness value is determined by each time-varying misaligned shaft angle. Effects of the misaligned shaft angle on the vibration features are analyzed by the mode, time-domain, frequency-domain and statistical indicator features. Meanwhile, experimental research is provided to verify theoretical results. The results show that the misaligned shaft angle can affect the mode of the system and decline the meshing stiffness. The change in the natural frequency is related to the decrease in stiffness. The gear torsional vibration signal is more sensitive to the misaligned shaft angle than the bearing translation signal. The purpose of this research is to provide some useful references in the numerical modeling gear system and monitor the contact state of the teeth.