基于球杆仪检测五轴数控机床主轴的热误差  

Thermal error measurement of spindle for 5-axis CNC machine tool based on ball bar

作　　者：何振亚[1,2] 傅建中[1] 陈子辰[1] 

机构地区：[1]浙江大学机械工程学系浙江省先进制造技术重点实验室,浙江杭州310027 [2]华南理工大学机械与汽车工程学院广东省精密装备与制造技术重点实验室,广东广州510640

出　　处：《光学精密工程》2015年第5期1401-1408,共8页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.51175461);高等学校博士学科点专项科研基金资助项目(No.20120101110055);华南理工大学中央高校基本科研业务费资助

摘　　要：提出了一种基于球杆仪的主轴热误差检测新方法用于五轴数控机床主轴热误差的便捷检测。该方法借助五轴数控机床的两个旋转轴分别单独运动,实现两个正交圆或圆弧构成的球杆仪空间轨迹测量;采用最小二乘方法对测量数据进行处理,求解主轴空间位置;通过初始状态和经过一定时间间隔测量多组数据,分离得到相应时间段的主轴热误差,包括1个轴向热伸长和2个径向热误差。以双转台五轴数控机床为例,从安装方法、测量步骤和辨识原理等方面介绍基于球杆仪的主轴热误差检测方法,并与ISO 230-3中的5点法进行了对比实验。实验结果显示:该方法的辨识结果与5点法测量结果的平均相对偏差小于15.8%,验证了本文方法的可行性和有效性。该方法测量装置简洁,便于携带、安装和测量,测试结果可为五轴数控机床主轴热误差补偿提供依据,从而有效地提高机床的加工精度。A novel method based on a ball bar to measure the thermal errors of machine tool spindles was proposed to compensate the thermal error of 5-axis Computer Numerical Control（CNC）machine tools.With the help of the movements of the two rotational axes,the volumetric paths comprised of two orthogonal circles or arcs were measured by the ball bar.The least square method was used to process the measurement data to obtain the volumetric positions of the machine tool spindles.Through frequently testing with this method at certain intervals,the thermal errors of machine tool spindles could be calculated,including 1axial elongation and 2radial thermal errors.To explain thismethod,a 5-axis CNC machine tool with a titling rotary table was taken as an example to elaborate the installation,measurement procedure and the identification principle.Finally,a contrast experiment was conducted with the 5-point method mentioned in ISO 230-3.The result shows that measurement results of the presented method are consistent with those of 5-point method mentioned in ISO 230-3and the mean relative deviation of the two methods is less than 15.8%,which verifies the feasibility and reliability of the presented method.The equipment is concise,portable,and easy to install.Moreover,the obtained results could be used for thermal error compensation of spindles to improve the machining precision of 5-axis machine tools.

关 键 词：五轴数控机床 主轴 热误差 误差测量 球杆仪 

分 类 号：TG659[金属学及工艺—金属切削加工及机床]