深孔变刚度/阻尼钻削系统的建模与稳定性研究

A dynamic model and stability of cutting tools with varying stiffness and damping in the deep-hole drilling process

依据深孔钻削刀具系统的实际布局形式,构建了包含有变刚度/阻尼辅助支撑的深孔加工刀具系统模型,模型中考虑了引发陀螺效应及切厚再生效应的因素。以Euler-Bernoulli梁单元模型为基础,运用矩阵传递函数方法,使得更多至关重要的局部设计信息融入进深孔刀具系统动力学方程,例如变刚度/阻尼辅助支撑、授油器及刀具结构形式等。通过理论计算与实验结果的对比,证实了该模型的准确性与可行性。以此为基础,结合频域特征向量的稳定性判据,研究了综合陀螺效应及切厚再生效应影响因素条件下深孔钻削刀具系统的稳定性与加工转速、钻削深度及施加的励磁电流之间的关联关系,验证了新型变刚度/阻尼钻削系统对提升刀具系统稳定性的有效性,这些将为实现深孔切削刀具振动行为带有目标性地主动式调控奠定基础。

Considering the practical layout of tool systems in deep-hole drilling,a drilling system model with varying stiffness and damping support was proposed,which includes a gyroscopic effect and regenerative chatter.Relying on the Euler-Bernoulli beam theory and the transfer matrix method,some important locally-designing information in detail could be considering,such as the intermediate support,oil supply device and cutting tool parameters.A series of experimental investigations was carried out to confirm the accuracy and effectiveness of the dynamic model proposed in this paper.Based on the aforementioned content,the dynamic stability features based on conditions of various drilling depths,tool rotation speeds and electric currents applied were obtained,and the effect of intermediate support with varying stiffness and damping was validated in the phenomenon of lobe suppression.These relevant results built a solid foundation for predicting and targeting active control of vibration behaviors in the deep-hole machining process.