五轴数控加工中心全域热特性评估方法

Global thermal characteristics evaluation method for five-axis CNC machining center

对于数控加工中心的热特性测试,国际标准ISO 230-3∶2020中所涉及的“五点测量法”的热误差补偿是基于工作台上固定单点。然而,研究发现该法忽略了工作台不同位置存在热误差差异的现象,造成模型对整个工作台的预测精度降低。因此,根据国际标准,选择五轴数控加工中心为研究对象,提出了结合模型预测效果的机床热特性检测方法和评估标准。研究结果显示:相比于传统单点建模,全域模型可以显著降低热误差差异对整个工作台精测效果的影响,能更加有效地展现机床的实际性能。

For the thermal characteristic test of CNC machining centers, the thermal error compensation of the “five-point measurement method” involved in the international standard ISO 230-3:2020 is based on a fixed single point on the workbench. However, the study finds that this method ignores the phenomenon of thermal error differences in different positions of the workbench, resulting in the decrease in the prediction accuracy of the model for the entire workbench. Therefore, on the basis of international standards, the five-axis CNC machining center is selected as the research object, and the thermal characteristics detection method and evaluation standard are proposed that the thermal characteristics of the machine tool need to be combined with the model prediction effect. The research results show that compared with the traditional single-point modeling, the global model can significantly reduce the influence of thermal error differences on the precision measurement effect of the entire workbench, and can more effectively show the actual performance of the machine tool.