The Influence of Gear Shaft Misalignment Fault on Time-Varying Mesh Stiffness of Helical Gear Pairs

Abstract

Abstract

Abstract Helical gear pairs are widely utilized in various mechanical systems due to their superior transmission performance. However, misalignment faults in gear shafts significantly impact their mesh stiffness, resulting in problems such as poor load distribution and heightened vibration and noise. To address the challenge that existing computational models struggle to balance prediction accuracy and computational efficiency, this paper focuses on two typical faults: parallel misalignment and angular misalignment of gear shafts. We propose a comprehensive iterative calculation model for the time-varying mesh stiffness (TVMS) of helical gears. The primary contribution of this model is its approach to understanding the underlying mechanisms of non-uniform variations in the contact surface region, which are induced by eccentric faults. It effectively integrates traditional tooth piece iterative calculations with additional contact line iterative calculations. Furthermore, it takes into account the changes in the contact surface region resulting from misalignment and variations in time-varying meshing geometric parameters, thereby accurately capturing the evolution of TVMS. The research range for parallel misalignment is 0 to 100 μm. When a parallel misalignment fault occurs, the overall TVMS of the helical gear shows an overall attenuation trend. The research range for angular misalignment is from 0 to 1.0°. When an angular misalignment fault occurs, the three-tooth meshing zone is significantly reduced, while the two-tooth meshing zone is extended. By comparing theoretical analyses with finite element results, and observing consistent trends across various operating conditions, this study provides reliable theoretical support for system fault diagnosis and optimization design.