Effect of the radial support stiffness of the ring gear on the vibrations for a planetary gear system

Planter gear system is one of the critical components of various industrial transmission systems. In general, the ring gear is elastically fixed with the gearbox. The gearbox materials and their assembly relationships will affect the support stiffness of the ring gear and system vibrations. In this paper, a multi-body dynamic model for a planetary gear system with the elastic support of ring gear is developed to discuss the influence of the radial support stiffness of ring gear on the system vibrations. The planet bearings are also considered in the multi-body dynamic model. The rotational speed of the planet gear and carrier from the simulation and theoretical results are compared to validate the developed multi-body dynamic model. The influences of the radial support stiffness of the ring gear, carrier moment, and sun gear speed on the time- and frequency-domain vibrations of the planetary gear system are analyzed. The results denote that the waveform and amplitude of the time-domain vibration of the ring gear are greatly affected by the radial support stiffness of ring gear as well as the peak frequency amplitude and its sidebands. The peak frequency in the spectrum of ring gear is slightly affected by the radial support stiffness. It indicates that this study can give some guidance for the vibration control approaches for the planetary gear systems.