高速列车轴箱圆柱滚子轴承启动过程的打滑动力学特性

Skidding dynamic characteristics of axle box roller bearing of high-speed trains during start-up

轴箱轴承的动力学性能对列车安全、平稳运行有非常重要的影响。基于刚性套圈假设建立轴承内部变形几何关系,采用Hertz接触理论描述滚子与套圈的接触关系,采用线性压缩弹簧来模拟滚子与保持架之间的相互作用,考虑拖动系数随滑移速度的非线性关系计算滚子与套圈的摩擦力,建立考虑内圈、滚子和保持架自由度的圆柱滚子轴承的动力学模型,研究轴承启动过程中的运动学特性和力学特性。结果表明:在轴承启动过程中,滚子自转转速抖动上升;启动初始阶段滚子打滑明显,其中滚子在刚进入承载区时出现的打滑对轴承性能影响较大;轴承启动的初始阶段,滚子与内圈的摩擦力和与保持架的接触力变化剧烈,且随内圈角加速度的增大而增大。

The dynamic performance of axle box bearing has great effect on the safety and steady running of high-speed train. The internal deformation relationship was built based on rigid ring assumption.The contact relationship was described using Hertz contact theory.The interactions between rollers and cage were simulated by linear compression spring.The friction forces between rollers and the rings were calculated considering variation relationship of drag coefficient with slip velocities.The dynamic model of cylindrical roller bearing was built considering the freedoms of inner ring, rollers and cage.The kinematic and mechanical properties of the bearing during start-up were studied. The results show that in the process of bearing start-up, the roller rotation speed jitteringly increases.In the initial stage of start-up, the roller skidding is obvious, in which the skidding of the roller just entering the loading area has a great influence on the bearing performance.In the initial stage of bearing start-up, the friction force between the roller and the inner ring and the contact force between the roller and the cage change violently, and increase with the increase of the angular acceleration of the inner ring.