镗铣加工中心主轴系统热误差测量实验研究

Experimental Study on Thermal Error Measurement of Spindle System of Boring and Milling Machining Center

目的通过对TX1600G复合式镗铣加工中心主轴部件热误差测量实验研究,找到主轴热关键点位置,检测其温升情况以及其热变形,进而确定产生热误差的主要影响区域.方法设计温度与热误差测量实验方案,采用红外热像仪布置和优化温度测点,并采集温度数据,对比各位置测点的温升情况确定热关键点;采用API主轴分析仪测量X、Y、Z三个方向的热变形值,对比数据进而确定热变形最大的方向.结果主轴在转速3 000 r/min下,当实验达到热平衡时,Z向热伸长最大;主轴中部的前后端轴承位置的温升较大,为热关键点,且Z向热变形曲线与温升曲线的趋势基本相同.结论加工中心主轴在实际运行中的误差主要是由温升引起的轴向热伸长误差,控制Z向伸长热变形能有效地提高加工精度.

The purpose is to find the position of the thermal key point of the spindle,detect the temperature rise and its thermal deformation and further determine the main area influenced by the thermal error by research on the thermal error measurement of the spindle of the TX1600 G composite boring machining center. The temperature and thermal error measurement acquisition scheme is designed,and the temperature measurement points are arranged and optimized by infrared thermal imager. The temperature data are collected and the thermal key points are determined by comparing the temperature rise of each measuring point. The thermal deformation of XYZ in three directions was measured by the API spindle analyzer,and the relative data were determined by the comparison data. The results showed that Z direction is the largest thermal elongation direction in the case of the spindle speed of 3 000 r/min and the achieved thermal balance. The temperature rise of the front and rear bearing positions in the middle of the spindle is larger,which is the ther-mal key points. The Z-direction thermal deformation curve is basically the same as the temperature rise curve. The conclusion is that the deviation in actual application of the main shaft for machining center is caused by the thermal expansion in axial direction when the temperature is rising. Therefore,it can effectively increase the processing precision through the coercion of thermal expansion and deformation in Z-direction.