行星齿轮箱线外啮合-故障冲击耦合激励现象学建模与分析

During the meshing process, the gear pairs often deviate from the theoretical meshing line, leading to corner contact mesh impacts. Under fault conditions, corner contact impacts increase significantly and form coupled excitation with fault impacts, influencing the vibration response of the planetary gear train. However, existing phenomenological models are found difficult to characterize this coupled impact excitation. For this reason, corner contact forces and stiffness variations in gear pairs under both healthy and faulty conditions are analyzed through the corner contact force and stiffness models, respectively. A meshing impact function is derived based on the meshing phase relationship, establishing a key link that characterizes the time-sequence correlation between corner contact forces, fault impact forces, and the meshing cycle. Based on this meshing impact function, a phenomenological model under the coupled excitation of corner contact mesh - fault impacts is developed. The matching synchrosqueezing transform method is employed to analyze the response characteristics under the impact excitation. Simulation and experimental signal analysis results under different fault sizes show that sideband amplitude and time-frequency energy increase with growing fault size. Capitalizing on this phenomenon, the fault evolution patterns is quantitatively characterized using FM0 and MSET energy spectra. The concordant variation patterns observed in simulation and experimental results validate the effectiveness of the proposed model in characterizing coupled impact excitation.