辨识HSK主轴-刀柄结合部参数,是准确预测主轴系统动态特性及保证切削稳定性的基础条件。将HSK主轴-刀柄结合部简化为弹簧-阻尼模型。再根据HSK主轴-热装刀柄系统的频率响应矩阵,推导出HSK主轴-刀柄结合部的刚度矩阵。并基于耦合响应法计算热装刀柄两端的频响矩阵,利用有限差分法与实验测量相结合的方式,分别获得HSK主轴端点和HSK主轴-热装刀柄系统端点的频响矩阵。基于推导出的结合部刚度矩阵,分别辨识出HSK主轴-刀柄结合部的4个刚度参数kyf、kθf、kym和kθm,以及4个阻尼参数cyf、cθf、cym和cθm.使用耦合响应法计算出HSK主轴-热装刀柄端点的频响函数,并与实验测量的各阶频率相比较,理论频率与实验结果最大差值为7.9%,进而验证辨识参数的准确性和辨识方法的合理性。
The basic condition for predicting the dynamic performance of spindle system and keeping the cutting stability is to identify the parameters of HSK spindle-toolholder joint part. HSK spindle-toolholder joint part is simplified as spring-damp model. According to the frequency response function( FRF) matrix of HSK spindle-shrink toolholder system,the stiffness matrix of HSK spindle-toolholder is derived. the FRF matrix of shrink toolholder is obtained based on coupling response method. The FRF matrixes of the tip points of HSK spindle and HSK spindle-shrink toolholder system are got by using finite difference method and experiment. Four stiffness parameters( kyf,kθf,kymand kθm) and four damp parameters( cyf,cθf,cymand cθm) are identified with the stiffness matrix. FRF of tip point of HSK spindle-toolholder sys-tem is achieved by using the coupling response method. The calculated frequency of HSK spindle-toolholder system is compared with the experimental frequency. The maximal difference between theoretical and experimental results is 7. 9%.