降低精密数控车床进给轴热误差对切削精度影响的方法

精密数控车床批量加工零件的精度稳定性是衡量机床性能的重要指标，其中加工过程中的进给轴受热伸长是影响加工精度的重要因素之一。对数控车床进给轴热变形方向及伸长量进行研究，对比丝杠预拉伸及数控系统热误差补偿功能，指出这两种降低进给轴热误差方法局限性，提出一种使用中空油冷循环系统降低进给轴热误差的方法。该中空油冷循环系统，一方面通过中空丝杠内循环的冷却油带走丝杠螺母的发热量，另一方面通过轴承室内循环冷却油带走轴承的发热量。进行了系统结构设计与实验验证，结果表明该系统可以使进给系统在加工时保持温度稳定，降低热误差，进而提升批量加工的精度稳定性。

Methods of Reducing the Influence of Thermal Errors of Feeding Shaft on Cutting Accuracy of Precision CNC Lathe

The accuracy stability of precision CNC lathe batch is an important indicator to measure the performance of machine tools.Thermal elongation of the feeding shaft during machining is one of the most important factors affecting machining accuracy.By studying the direction of thermal distortion and elongation of feeding shaft, screw pre-stretching and CNC thermal error compensation function were compared, the limitations of these two methods were studied, a method to reduce the thermal error of the feeding shaft by using a hollow oil cooling circulation system was proposed. In this hollow oil cooling circulation system, the heat generated by the screw nut was took away through the cooling oil circulated inside the hollow screw, and the heat generated by the bearings was took away through the cooling oil circulated inside the bearing chamber. Structural design and experimental verification were carried out. The results show that the system can make the feed system maintain temperature stability during machining,so thermal error is reduced and the accuracy stability of batch machining is improved.