考虑摩擦动力学特性的TI环面蜗杆传动弹流润滑分析

Analysis of Elastohydrodynamic Lubrication Performance for TI Hourglass Worm Drive with Considering Tribo-dynamics Character

综合考虑时变啮合刚度、传递误差和粗糙峰摩擦因数的影响,基于载荷分担理论和动力学理论建立了TI环面蜗杆传动副简易动力学模型,将摩擦动力学特性考虑到线接触弹流润滑理论(EHL)中,求解获得啮合周期内轮齿的啮合力与摩擦力变化趋势,绘制了不同参数下油膜压力和油膜厚度的分布情况。计算结果表明,低速时,啮入端的轮齿啮合力和摩擦力均大于高速时的啮合力和摩擦力;螺旋角增大,啮入端和啮出端的轮齿啮合力都明显增大;轮齿摩擦力随转速变化较小。最大摩擦力值降低,可提高蜗轮副传动寿命;轮齿啮合刚度对油膜压力和油膜厚度的影响最大,轮齿啮合力和粗糙峰摩擦因数影响较小。

The simple tribo-dynamics model for TI hourglass worm drive is proposed based on the load sharing theory and dynamic theory,which took the time-varying mesh stiffness,transmission error and friction coefficient of rough peak into account.The tribo-dynamics character is considered into line contact Elastohydrodynamic Lubrication(EHL).The meshing force and friction changes,oil film pressure and thickness distribution are obtained by calculation.The calculation results show that,when at low speed,the meshing force and friction of the tooth are larger than those at high speed.With the increase of the helix angle,the meshing forces both at inlet and outlet are obviously improved,and the friction of the tooth changes a little with the speed.Meanwhile,the maximum friction reduces,which can improve the transmission life of the worm drive pair.The meshing stiffness of the tooth has the greatest impact on oil film pressure and thickness,and the meshing force and friction coefficient of rough peak have less influence correspondingly.