Dynamic modeling and stability analysis for the combined milling system with variable pitch cutter and spindle speed variation.

Variable-pitch cutter and spindle speed variation are two well-known methods to suppress milling chatter by disrupting regenerative effect. Considering their compatibility in practical application, their combined system perhaps has better potential for chatter suppression. However, to authors’ knowledge, there has been little research associated with this issue. In this paper, a milling dynamic model, which can simultaneously take into account the effect of the variations of cutter pitch angles and spindle speed, is constructed and linear stability analyses are carried out via an updated semi-discretization method, which has great capability to predict the stability lobes of milling process with multiple time-periodic delays. Then, through comparisons with previously associated works along with time-domain simulations, the effectiveness of the proposed model is confirmed. Moreover, the combined influences of the new system and the main system parameters on stability are deeply evaluated and discussed by conducting lots of simulations. Results show that the combined milling process exhibits a great capability to avoid the onset of milling chatter and can result in nearly 3-fold increase in depth of cut than that of a tradition one, but 1-fold increase for the process with variable pitch cutter or variable spindle speed in some special cases. [ABSTRACT FROM AUTHOR]