基于振动信号特征频率的数控车床故障辨识方法

Fault identification method based on characteristic frequency of vibration signal for CNC lathe

针对数控车床切削件表面波纹故障源辨识问题,通过监测主轴振动信号进行时频域分析,初步确定波纹故障来源;采用滚动轴承故障特征频率计算方法,得到各轴承对应的故障特征频率,与振动信号时频域分析得到的特征频率进行对比分析,辨识得到切削件波纹故障源。通过主轴拆卸和切削实验,验证了文章所提故障辨识方法的有效性。实验结果表明:角接触球轴承内圈损伤是导致波纹故障的故障源,理论方法故障辨识结果与拆卸实验辨识结果一致;采用重装配后主轴的切削实验消除了波纹故障,进一步验证了该文章故障辨识方法的有效性。

Aiming at the problem of fault identification for surface corrugation of cutting parts by CNC lathe,the vibration signal of the main shaft is analyzed in the frequency domain,to generally know the source of corrugation faults.The fault characteristic frequency calculation method is used to obtain the fault char-acteristic frequency of each bearing.And the source of the corrugation faults is identified by comparing and analyzing the obtained characteristic frequency of each bearing.The effectiveness of the developed fault identification method is verified by spindle disassembly and cutting experiments.The experimental results show that the inner ring damage of the angular contact ball bearing is the source to cause the corrugation fault.The fault identification result from the developed method is consistent with the disas-sembly experiment identification result.The cutting experiment of the main shaft after reassembly elimi-nates the corrugation fault,which further validates the effectiveness of the developed fault identification method.