数控机床移动工作台定位精度预测的建模、仿真及实验  

Modeling,simulation and experiment of positioning accuracy prediction of moving table of NC machine tool

作　　者：杨洪涛[1,2] 秦鹏飞 李莉[1,2] 刘柄瑶 金磊 姜西祥 YANG Hongtao;QIN Pengfei;LI Li;LIU Bingyao;JIN Lei;JIANG Xixiang(School of Mechanical and Electrical Engineering,Anhui University of Science and Technology,Huainan 232001,China;State Key Laboratory of Mining Response and Disaster Prevention in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学机电工程学院,安徽淮南232001 [2]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,安徽淮南232001

出　　处：《机电工程》2025年第2期351-361,共11页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金资助项目(51675004);安徽省高等学校科学研究项目(2022AH050805);安徽理工大学引进人才科研启动基金资助项目(2021yjrc32);矿山智能装备与技术安徽省重点实验室开放基金资助项目(ZKSYS202207)。

摘　　要：随着使用时间的延长,数控机床移动工作台会出现部件磨损、失效等现象,进而导致工作台定位精度降低。为了精确预测移动工作台的精度损失,以数控机床移动工作台为研究对象,在考虑载荷、运动速度、温度和运行时间等影响因素的基础上,建立了工作台的定位误差预测模型,对工作台定位误差随时间的变化情况,进行了理论计算、仿真分析及实验验证。首先,在分析滚动直线导轨副的摩擦磨损机理和负载作用下产生的表面接触变形的基础上,建立了导轨副表面滚珠与滚道在接触载荷作用下的磨损模型,以及滚珠丝杆在电机扭矩、轴向力和温度作用下产生的扭转变形、螺距变化及热膨胀误差模型,还建立了工作台随使用时间变化的定位误差预测模型(因导轨副磨损与滚珠丝杆变形均会使工作台产生定位误差,两部分误差之和为定位精度损失预测模型);然后,开展了不同负载、运动速度、温度等因素影响下的理论计算与仿真分析;最后,在一组特定负载、速度、温度的条件下,进行了定位误差的测量实验,验证了上述预测模型的准确性。研究结果表明:在不同的因素影响作用下,仿真结果、实验结果与理论结果相比,其总体的变化趋势趋于一致,且经拟合对比分析,定位误差的仿真、实验与理论之间的最大相对误差为15.9%。该误差预测模型能够有效预测工作台的定位误差,为数控机床加工精度的预测奠定了基础。With the increase of use time,the mobile workbench will appear parts wear,failure,etc.,which will cause the positioning accuracy of the workbench to decrease.In order to accurately predict the accuracy loss of moving table,taking the moving table of CNC machine tool as the research object,considering the influence factors such as load,moving speed,temperature and running time,the positioning error prediction model of the worktable was established,and the variation of the positioning error of the worktable with time was theoretically calculated,simulated and verified by experiments.First,based on the analysis of friction and wear mechanism of linear rolling guide pair and surface contact deformation caused by load,the wear model of ball and raceway on the surface of linear rolling guide pair under contact load and the torsional deformation,pitch change and thermal expansion error model of ball screw under the action of motor torque,axial force and temperature were established.The positioning error prediction model was also established.The positioning error was caused by the wear of guide pair and the deformation of ball screw.The sum of the two errors was the positioning accuracy loss prediction model.Then,the theoretical calculation and simulation analysis were carried out under the influence of different load,speed,temperature and other factors.Finally,the accuracy of the model was verified by measuring experiments under a set of specific load,speed and temperature conditions.The research results show that under the influence of different factors,the overall change trend of the simulation results and experimental results is consistent with the theoretical results,and through fitting comparative analysis,the maximum relative error between the simulation,experiment and theory of positioning error is 15.9%.The error prediction model can effectively predict the positioning error of the workbench,laying a foundation for the prediction of the machining accuracy of CNC machine tools.

关 键 词：移动工作台运行时间 定位精度损失 定位误差模型 导轨副磨损模型 滚珠丝杆变形 热膨胀误差 

分 类 号：TH161[机械工程—机械制造及自动化] TG659[金属学及工艺—金属切削加工及机床]