一种新的切削刚度系数识别方法

NEW IDENTIFYING METHOD OF CUTTING STIFFNESS COEFFICIENT

在研究机床切削系统稳定性极限预测的过程中 ,切削刚度系数kc 的准确识别是其中最为关键的一项工作。文中在对刀架施加振动激励 ,变稳态切削为动态切削的基础上 ,以动态切削力为研究对象 ,推导切削刚度系数kc 的数学模型 ,并在切削试验中通过对动态切削力信号及其与振动位移信号相位差的测量 ,准确有效地识别切削刚度系数kc。试验结果表明 ,文中的切削刚度的识别方法可以为机床切削系统稳定性预测理论分析和试验研究提供更为准确的动力学参数。

The cutting stiffness coefficient k c is a very important parameter and its accurate recognition is the key factor for predicting machine tool system stability limit. On condition that the vibration exciter was applied to the cutter saddle to make the cutting process set in dynamic state, the mathematical model of cutting stiffness coefficient k c was build on studying dynamic cutting force. In testing system, the cutting stiffness coefficient k c was identified accurately in the dynamic cutting state though measuring the dynamic cutting force and the phase of dynamic cutting force-exciting displacement. The results show that the relative errors are less than 5% and this identifying method can supply the dynamic parameter more accurately for theoretical research and experimental investigation on predicting machine tool system stability limit.