车轮多边形激励下转向架齿轮箱轴承内部接触特性研究
Study on Internal Contact Characteristics of Bogie Gearbox Bearings under Wheel Polygon Excitation

转向架齿轮箱轴承作为列车走行部中的关键核心部件，其内部接触特性直接影响轴承的正常运行，进而影响列车走行部的安全稳定性。除齿轮箱内部的激励外，实际运行中还受到轮轨激励的显著影响，如车轮踏面磨耗等，其中车轮多边形为最常见的激励形式。本文以转向架齿轮箱输入端的圆柱滚子轴承为研究对象并建立其动力学模型，并通过内部零件的速度特征验证了模型的有效性。同时，提出了基于转向架轮轨耦合动力学模型的轮轨激励获取方法。在此基础上对比分析了不同车轮多边形激励幅值和阶次作用下转向架齿轮箱轴承的内部接触载荷特性的变化规律。结果表明：车轮多边形激励会导致在承载区内滚子与外圈接触载荷发生冲击现象，随着多边形阶次的增加，滚子与外圈接触载荷的冲击越频繁，随着幅值的增加，滚子与外圈接触载荷的冲击幅度越大；滚子与保持架的碰撞力已表现出显著的随机波动特性，引入车轮多边形激励后，随着车轮多边形阶次和幅值的增加，碰撞力的随机波动程度进一步增强。
As a key core component of the train running gear, the gearbox bearing of the bogie directly affects its normal operation through internal contact characteristics, which in turn impacts the safety and stability of the running gear. In addition to internal excitations from the gearbox, it is also significantly influenced by wheel-rail excitations during actual operation, such as wheel tread wear, with wheel polygonization being the most common excitation form. In this paper, taking the cylindrical roller bearing at the input end of the bogie gearbox as the research object, a dynamic model is established, and the model’s validity is verified through the velocity characteristics of internal components. Furthermore, a method for obtaining wheel-rail excitation based on the bogie-wheel-rail coupled dynamic model is proposed. On this basis, the variation patterns of internal contact load characteristics of the bogie gearbox bearing under different wheel polygon excitation amplitudes and orders are comparatively analyzed. The results show that wheel polygon excitation induces impact phenomena in the contact load between the rollers and the outer race within the load-bearing region. As the polygon order increases, the impact frequency of the roller and the outer ring contact load rises, and as the excitation amplitude increases, the impact magnitude of the roller and the outer ring contact load becomes larger. Additionally, the collision force between the rollers and the cage exhibits significant random fluctuation characteristics, which intensify with the increase in wheel polygon order and amplitude when wheel polygon excitation is introduced.