超精密加工中表面波纹度与主轴系统不平衡关系  

Relationship between Waviness in Ultra-precision Machining and Spindle Unbalance

作　　者：陈东菊[1] 范晋伟[1] 李海涌[1] 张飞虎[2] 

机构地区：[1]北京工业大学机械工程与应用电子技术学院,北京100124 [2]哈尔滨工业大学机电工程学院,哈尔滨150001

出　　处：《机械工程学报》2013年第1期191-198,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51105005);教育部博士点新教师基金(20111103120002)资助项目

摘　　要：针对超精密加工工件表面出现的表面波纹度问题,研究超精密机床液压主轴系统不平衡问题与表面波纹度之间的关系。加工工件的面形检测结果首先利用选出的最优小波变换进行各个尺度的分解及重构,接着利用功率谱密度分析小波分解后各个尺度上的信号谱能量得到相关频率信息,结合主轴系统部件的模态及旋转频率信息,对检测结果中主要误差特征进行提取。主轴系统频率信息由两种方法进行计算,从面形波纹度中提取出来的典型误差特征包含机床主轴固有频率和旋转频率及其高倍频,电源基频50 Hz及其整数倍频和次谐波信号,这些频率特征正好与主轴系统不平衡频率以及电动机工频噪声干扰频谱特征对应,这说明主轴系统不平衡是导致加工工件波纹度出现的主要原因,这种辨识方法为超精密机床加工精度的提高提供了辨识依据。For the problem of the workpiece waviness, the relationship between the spindle unbalance and waviness phenomenon is researched. The measured result of the workpiece is decomposed and restructured by the wavelet transform, then, the power spectral density is used to analyze the spectrum energy of the signal in each scale decomposed by wavelet transform, and the corresponding frequency is obtained. The modal information of the spindle system is calculated by two methods. The main errors features is extracted with the frequency information of the spindle system, it includes the natural frequency and rotating frequency of the spindle, and the spectrum of the alternating current interference of the motor, the basic power frequency is 50 Hz and its multiple integers, sometimes also includes sub-harmonic signal. The extracted features from the workpiece is agree with the unbalance frequency of the spindle system and the alternating current interference of the motor, this explains the spindle unbalance is the main reason for the waviness, and provide a identification basis for the improvement of the machining accuracy.

关 键 词：超精密车削 波纹度 主轴不平衡 小波变换 功率谱密度 

分 类 号：TH161[机械工程—机械制造及自动化]