Vibration sideband modulation mechanism and analytical signal modelling of the ring gear in a planetary gear set

To address the vibration and modulation sideband mechanism problems, this paper proposes a dynamic model for the planetary gear transmission (PGT). Based on the time-varying vibration transfer path analysis, a novel analytical vibration signal model is derived using the mode superposition method to study the vibration characteristics of the ring gear. In the presented signal model, we analyze the complicated modulation sidebands in terms of frequency and reveal the amplitude modulation effect of the carrier. Results show that amplitudes of modulation sidebands are slightly asymmetric for a single planet system, while the amplitudes of modulation sidebands are asymmetric for the multiple planets system. Furthermore, methods for suppressing the vibration are proposed by designing the appropriate planet position angles, meshing phasing, and load sharing performance. Finally, simulation and experimental signals are compared to verify the proposed model. The result shows that experimental signals keep good consistency with the simulated signals.