考虑粗糙度的倾斜式双滚柱包络环面蜗杆传动弹流润滑分析

Elasto-hydrodynamic lubrication analysis for an inclined doubleroller enveloped hourglass worm drive considering roughness

为了研究倾斜式双滚柱包络环面蜗杆传动共轭齿对在啮合传动过程中考虑粗糙度的润滑特性。根据该传动副的啮合理论,在弹性流体动力润滑理论基础上,基于牛顿流体弹流润滑模型建立了传动副的线接触简化模型和数学模型,考虑共轭齿面粗糙度对弹流润滑的影响,利用多重网格技术进行数值求解,得出一个共轭齿对从啮入到啮出不同啮合时刻的油膜厚度和油膜压力,并据此分析了滚柱半径、喉径系数、滚柱偏距、倾斜角对弹流润滑特性的影响。结果表明粗糙度的存在会造成传动副的油膜压力和油膜厚度产生波动,使最大油膜压力峰值增大,最小油膜厚度减小,因此粗糙度对该传动副的润滑是不利的;滚柱半径、滚柱偏距和倾斜角过大,喉径系数过小时,越不利于动压油膜的形成,对传动副的润滑越不利,要保持该传动副具有良好的润滑性能,滚柱半径、滚柱偏距和倾斜角不要过大,喉径系数不要过小。

To study lubrication characteristics of conjugate teeth pair in an inclined double-roller enveloped hourglass worm drive considering effects of roughness in transmission process,according to the mesh theory of this transmission pair,the line contact simplified model and mathematical model for the transmission pair based on the elastohydrodynamic lubrication（ EHL） model of Newtonian fluid were established. Considering the effects of conjugate teeth surface roughness on EHL of this worm drive,oil film pressure and thickness curves were gained by using the multi-grid method during a conjugate teeth pair meshing from gnawing in to out. At last,the effects of roller radius,orifice coefficient,offset distance and inclined angle on EHL were analyzed. It was shown that the conjugating teeth surface roughness makes the transmission pair’s oil film pressure and thickness fluctuate,the maximum oil pressure peak increase and the minimum thickness decrease,so the roughness is harmful to lubrication of the transmission pair; roller radius,offset distance and inclined angle should not be too big and orifice coefficient should not be too small,thus the inclined double-roller enveloped hourglass worm drive keeps good lubrication performance.