摘要
针对动静压柔性铰链可倾瓦轴承在受到阶跃载荷时主轴出现跳动而影响其回转精度的问题,提出了兼顾跳动幅值与稳定时间的分析方法和轴承优化设计方案。该方法基于轴心轨迹引入最大过冲量和过渡过程时间两个概念,用以描述主轴受到阶跃载荷时径向跳动的剧烈情况,研究轴承结构参数的确定方法。该方法首先建立轴承瓦块的压力分布模型、瓦块的力矩平衡方程和轴颈的运动方程,然后结合有限差分法和欧拉方法获取轴心轨迹,最后依据结构参数对两个参量的影响大小进行参数确定。仿真实验结果表明:增大预载荷或减小轴承半径间隙,能减小轴心最大过冲量并缩短过渡过程时间;减小静压油腔面积或油腔宽长比能减小最大过冲量;过渡过程时间随转速的提高呈现出先增加后减少的特点;在研究范围内,最大过冲量随着转速提高而增大;适当增大预载荷系数或减小半径间隙,能够提高主轴的回转精度。
The journal radial runout of a hybrid flexure pivot-tilting pad bearing is analyzed under step load to improve the spindle rotation accuracy.The influences of the bearing structure and operating parameters on spindle rotation accuracy are investigated by analyzing the maximum overshoot and the transition time of the journal.A pressure distribution model and a torque balance equation of pads,as well as a journal movement equation,are established.Numerical simulation results of the rotor center trajectory are obtained by combining the finite difference method with the Euler method.The results show that when the rotational speed keeps the same,the maximum overshoot and the transition time reduce by either increasing the preload or reducing the radius clearance.Reducing the area or width-length ratio of the oil chamber decreases the maximum overshoot.When the width-length ratio is the same,the transition time increases at the beginning and then decreases with the increasing of rotational speed.The maximum overshoot increases with the increasing of rotational speed within the certain scope.These results indicate that the spindle rotation accuracy can be improved by either increasing the preload coefficient or reducing the radius clearance.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2017年第8期96-101,共6页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(51575318)
关键词
柔性铰链可倾瓦轴承
轴心轨迹
过渡过程时间
最大过冲量
flexure pivot-tilting pad bearing
rotor center trajectory
transition time
maximum overshoot
作者简介
李吴（1991-），男，硕士生；;陈淑江（通信作者），男，副教授。
