主轴-刀柄-刀具系统刀尖频响函数的预测方法研究

Tool nose FRF prediction of a spindle-holder-tool system

为了获取稳定性Lobe图必需的刀尖频响函数,以考虑转动惯量和剪切变形的Timoshenko梁理论建立主轴、刀柄和刀具模型,并结合传递矩阵法和动柔度耦合子结构分析技术(RCSA),提出一种新的刀尖频响函数预测方法。和模态叠加法计算结果相比较,可以发现,该方法具有更高的计算精度和效率。这种预测方法有助于快速获取精确的刀尖频响函数,从而能高效地绘制出高精度的稳定性Lobe图,为保证高速切削过程的稳定性打下坚实基础。

Tool nose frequency response function （FRF）is necessary to construct a stability Lobe diagram.Based on Timoshenko beam theory considering rotary inertia and shear deformation,all components of a spindle-holder-tool assembly were modeled as a multi-segment Timoshenko beam.Here,a new method to predict its tool nose FRF was proposed by using the transfer matrix and the receptance coupling substructure analysis （RCSA）method.Comparing the results using the new method with the calculation ones of the modal superposition method,the effectiveness of the proposed method was verified.It was shown that the new prediction method can help to obtain tool nose FRFs of machine tools more precisely and quickly,so more accurate stability Lobe diagrams can be achieved,and it can lay a foundation for ensuring the stability of high speed cutting processes.