【摘要】 针对滚动轴承局部故障动力学建模问题，通过分析各滚动体在进入、退出载荷区和陷入故障时的变化情况，基于Hertz接触理论，定义了接触变形保留因子，提出了滚动轴承等效时变刚度函数，建立了局部故障滚动轴承单自由度时变刚度动力学模型，并进行了理论分析和试验研究。研究结果表明：当滚动体进入或退出载荷区时，载荷区中承载滚动体数量增加或减少，引起系统等效时变刚度的小幅增加或减小；当滚动体陷入故障时，因接触变形保留因子的不同使得其有效接触刚度不同程度降低而导致系统等效时变刚度的减小。系统等效时变刚度的变化引起载荷区中其他滚动体的接触变形和接触力产生不同幅度的变化，从而平衡外部径向载荷，对载荷区中心附近的滚动体的影响较为明显，但不影响各滚动体的有效接触刚度。系统等效时变刚度发生突变，导致系统振动。当外环故障时，等效时变刚度等幅变化；当内环故障时，等效时变刚度的变化受到内环旋转的调制而幅值不同。提出的单自由度时变刚度动力学模型与实际更加吻合。更多还原

【Abstract】 Here, aiming at the dynamic modeling problem for local faults of rolling bearing, by analyzing changes of each rolling element when entering or exiting load zone and falling into a fault, based on Hertz contact theory, the contact deformation retention factor was defined, the equivalent time-varying stiffness function of rolling bearing was proposed, and a single-DOF time-varying stiffness dynamic model for rolling bearing local fault was established. Theoretical analysis and experimental study were conducted. The study results showed that when rolling elements enter or exit load zone, the number of load-bearing rolling elements in load zone increasing or decreasing can cause small increase or decrease in equivalent time-varying stiffness of the system; when a rolling element falls into a fault, its effective contact stiffness decreases to different levels due to different contact deformation retention factors to cause decrease in equivalent time-varying stiffness of the system; variation of the system’s equivalent time-varying stiffness can cause changes to different levels in contact deformation and contact force of other rolling elements in load zone so that external radian load is balanced, rolling elements near load zone center are affected more obviously, but effective contact stiffness of each rolling element is not affected; the system’s equivalent time-varying stiffness having a sudden change can cause system vibration; during outer ring failing, equivalent time-varying stiffness varies constantly; during inner ring failing, variation of equivalent time-varying stiffness is modulated by rotating of inner ring and has different amplitudes; the proposed single-DOF time-varying stiffness dynamic model is more in line with reality.更多还原