基于球杆仪的三轴数控机床热误差检测方法

热误差是影响机床加工精度的主要误差项．为了快速检测机床自身热误差，在研究机床综合误差和球杆仪检测原理的基础上，提出了一种快速有效的检测方法——球杆仪法．通过建立三轴数控机床的几何误差和热误差的综合误差模型，提出机床的几何误差和热误差的检测及分离方法，并对影响加工精度较大的主轴与Z导轨的平行度误差、标尺热变形导致的比例误差以及滚珠丝杠变形导致的周期性误差等主要热误差项进行了球杆仪圆轨迹测试法的模拟仿真，通过进行球杆仪检测实验，测得机床空载时的主轴端热漂移误差，得到其变化规律曲线．相对于传统热误差检测法，该方法简捷有效．

Double-Ball-Bar-Based Thermal Errors Measurement Method for 3-Axis CNC Machine Tool

Thermal errors are major contribution to the accuracy of machine tool.To measure the thermal errors of the machine tool quickly,double-ball-bar(DBB) method was presented as a simple measurement method based on analysis of the integrated errors of machine tool and the measurement principle of DBB.First,a integrated error synthesis model,which consists of both geometric errors and thermal errors of 3-axis CNC machine tool,was derived.Then the measurement method and separate method of the two kinds of errors were proposed.Second,the results of the DBB measurement for spindle thermal drifts errors which influence the accuracy greatly,such as the parallelism error between spindle and guide way of the Z-axis,the scaling mismatch error caused by thermal deformation of staff gauge and the cyclic error caused by deformation of the ball screw shaft were(simulated.) At last,DBB was used to measure the spindle thermal drifts errors in the experiment and the(regularity) of the errors was drawn in pictures.Obviously,the novel thermal errors measurement method based on DBB is more effective compared with traditional measurement systems.