Analysis and Compensation Study on Influence of Workpiece Load on Positioning Error of Machine Tool
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摘要: 影响机床精度的因素众多,其中,工件载荷对机床产生的误差同样不可忽视。通过对机床的受载情况进行静力学分析,并利用激光干涉仪对机床的定位误差及其他各项几何误差进行测量,其结果显示,工件载荷对机床的几何误差存在很大影响,尤其在定位精度上,加载100 kg与空载相差10%左右,并且在进行误差补偿之后,这一差距会提升到40%左右,在此基础上提出了结合载荷的定位误差补偿方法。该方法解决了螺距误差补偿在实际工况下会产生欠补偿或过度补偿的问题。Abstract: There are many factors affecting the accuracy of machine tools, among which the error caused by workpiece load can not be ignored. Through the macro statics analysis of the loading condition of the machine tool, the positioning error and other geometric errors of the machine tool are measured by using the laser interferometer. The results show that the workpiece load has the significant influence on the geometric error of the machine tool, especially in the positioning accuracy, the difference between the load of 100 kg and the no-load is about 10%, and after the error compensation, the difference will be increased to about 40%. Therefore, the positioning error compensation method combined with the load is proposed. This method solves the problem of under compensation or over compensation of pitch error compensation in actual working conditions, and provides theoretical guidance for further improving the positioning accuracy of machine tool in working conditions.
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Key words:
- workpiece load /
- mechanical analysis /
- positioning error /
- error compensation
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表 1 定位精度A受载前后对比
Table 1. Positioning accuracy A comparison before and after loading
载荷重量/kg X轴定位误差/μm X轴沿Z轴方向
直线度误差0 34.267 31.900 100 28.966 28.490 影响比例/% 15.5 10.7 表 2 定位精度A补偿前后对比
Table 2. Positioning accuracy A comparison before and after compensation
载荷重量/kg X轴定位误差/μm 补偿前 补偿后 0 34.267 18.414 100 28.966 10.968 影响比例/% 15.5 41.9 -
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