变轴数控机床重复定位精度评定策略探讨

A Discussion on the Scheme of Evaluation for the Positioning Repeatability in Variable-Axes Numerical Control Machine Tools

参照传统数控机床位置精度评定项目 (GB10 931— 1989)中关于重复定位精度的内容 ,结合 BKX- I型变轴数控机床的特点拟定了评定策略 .通过检测及分析 ,对该机床的重复定位精度进行了评定 ,确认其重复定位误差不大于 2 0μm,同时存在误差耦合现象 .在目前缺乏相关评定标准的情况下 ,此项研究结果为基于并联机构的机床性能评定方法研究提供了参考 .

The scheme of evaluation for the positioning repeatability in variable axes numerical control machine tools(VNCMT) is studied. It refers to relevant items regarding the positioning accuracy of conventional NC machines taking into consideration characters of VNCMT. The positioning repeatability of machine model BKX I is evaluated as a typical case. The results indicate that the error of positioning repeatability is not in excess of 20 μm, and a coupling among all kinds of errors in VNCMT exists. These trials may offer a reference for further study of similar kinds of machine tools.