切削加工系统的稳定性分析

本文根据一台数控车床的实际加工过程,建立了切削系统的动力学模型,并导出了切削过程闭环系统的传递函数。这一动力学模型,概括了再生型颤振和振型耦合颤振原理。稳定性分析所用的结构传递函数和动态切削力系数,是根据切削系统解耦的条件,在切削过程中辩识和测量得到的。稳定性分析得到的极限切削宽度值与切削颤振试驻的实验值,可良好地吻合。稳定性极限值的大小与左刃或者右刃切削方式,走刀量以及切削速度等因素有关。文中建立的切削过程动力学模型和稳定性分析方法,可用于预测加工过程的稳定性。

Stability Analysis of Machining System

In this paper,a dynamic cutting model and its transfer function of the closedloop cutting process have been developed based upon the real cutting process on anNC lathe.In this model the mechanisms of regenerative and coupling chatter aredescribed simultaneously.The structural transfer functions and the dynamic cuttingforce coefficients for the stability analysis have been identified in the cutting processby using the decoupling conditions of the system.The results from theoreticalanalysis and experimental investigation agree very well.It is shown that the amplitudeof critical cutting width is concerned with some factors such as the pattern of leftor right hand cutting,the feed and the cutting velocity.The model proposed in thisarticle would be used to predict the stability during the machining process.