Time-Varying Mesh Stiffness Calculation and Dynamic Modeling of Spiral Bevel Gear with Spalling Defects

Time-varying mesh stiffness (TVMS) is a vital internal excitation source for the spiral bevel gear (SBG) transmission system. Spalling defect often causes decrease in gear mesh stiffness and changes the dynamic characteristics of the gear system, which further increases noise and vibration. This paper aims to calculate the TVMS and establish dynamic model of SBG with spalling defect. In this study, a novel analytical model based on slice method is proposed to calculate the TVMS of SBG considering spalling defect. Subsequently, the influence of spalling defect on the TVMS is studied through a numerical simulation, and the proposed analytical model is verified by a finite element model. Besides, an 8-degrees-of-freedom dynamic model is established for SBG transmission system. Incorporating the spalling defect into TVMS, the dynamic responses of spalled SBG are analyzed. The numerical results indicate that spalling defect would cause periodic impact in time domain. Finally, an experiment is designed to verify the proposed dynamic model. The experimental results show that the spalling defect makes the response characterized by periodic impact with the rotating frequency of spalled pinion.