单摆角五轴数控机床摆头几何误差测量与精度验证

Geometric error measurement and accuracy verification of the swing head of a five-axis CNC machine tool with a single swing angle

摆角精度是影响五轴数控机床加工性能的关键因素,而对摆头各项几何误差进行准确测量是机床实际应用过程中的重要技术环节。该文以一台用于航空发动机机匣加工的单摆角五轴数控机床为研究对象,对其摆头几何误差进行了测量,并完成了精度验证。首先,介绍了摆头直驱五轴数控机床的整体结构,针对主轴端面至A轴回转中心距离偏差、摆头摆动扇面与YZ平面偏差和主轴轴线与A轴轴线高度差等摆头主要几何误差,提出了实用的测量方法,并开展了相应的测量实验;其次,对摆角定位精度进行了检测并分析了相应的位置偏差;最后,完成了机匣模拟试件切削。检测结果表明试件符合加工要求,充分证明了样机具有良好的摆角精度。该文所提出的误差测量方法为提升五轴数控机床的实际加工性能奠定了基础。

The swing angle accuracy is a key factor which strongly affects the machining performance of five-axis CNC machine tools and accurate measurements of the geometric error. This study measured the geometric swing head error of a five-axis CNC machine tool designed for machining aero-engine casings to verify the accuracy. This paper described a machine tool structure with a single direct-drive swing head and measurements of the main geometric errors of the swing head, including the deviation from the spindle end-face to the rotational center of the A-axis, the deviation between the swing sector and the YZ plane, and the height difference between the spindle axis and the A-axis. Then, the swing angle positioning accuracy was measured with the related position error. A cutting test on a simulated aero-engine casing showed that the machine tool swing angle accuracy was sufficiently accurate to properly machine the casing. The methods presented in this paper provide a foundation for improving the machining accuracy of five-axis machine tools in industry.