时变支承刚度对分流传动系统振动特性的影响

Influence of Time-Variant Supporting Stiffness on Vibration Characteristics of Split-Torque Transmission System

基于集中质量法,考虑时变啮合刚度、综合传递误差和齿侧间隙等因素的影响,建立了圆柱齿轮分流传动系统的弯扭耦合动力学模型和方程。采用变步长Runge-Kutta法,对动力学方程进行了数值求解;通过引入滚动轴承的支承刚度计算模型,分析了时变支承刚度和非时变支承刚度对系统振动特性的影响。仿真结果表明:当按照时变支承刚度模型计算时,轴承的支承刚度会产生4%左右的波动,输出轴上的横向振动位移幅值增大了约5%;支承刚度的时变性使得系统的非线性增强,稳定性变差;支承刚度的时变特性对分扭级动载系数影响较大,对并车级动载系数影响较小。

A bending-torsional coupled dynamics model of the split-torque transmission system is developed based on the theory of the lumped parameter method.The time-varying meshing stiffness,general transmission errors and the backlash are introduced in dynamics model and dynamics equations.Using the Runge-Kutta numerical integral method with varied steps,the dynamical equations are solved.In order to analyze the influence of time-variant and time-invariant supporting stiffness on the vibration characteristics of the system,the model of supporting stiffness of rolling element bearing is introduced.The results show that：the stiffness of the bearing fluctuates at about 4% and the transverse vibration displacement amplitude of the output shaft increases about 5% according to time-variant models.The time-variant characteristic of supporting stiffness enhances the nonlinearity and instability of the system.The time-variant characteristic of supporting stiffness has the larger influence on the dynamic load coefficient of the split torque stages than that of the synthesized torque stages.