Abstract
It is known that a stability limit of regenerative chatter vibrations in end–milling process takes a lot of local maximum values with increase in spindle speed. Therefore, the final purpose of this study is to suppress regenerative chatter vibrations by adjusting automatically spindle speed. For this final purpose, some parameters in dynamic cutting process were estimated by wavelet analysis of spindle head vibrations of a machining center and considered the relation between the parameters and the stability limit in this paper. The parameters of dynamic cutting process adopted in this paper are peak value, dominant frequency, and phase angle between the present vibrations and the previous vibrations at dominant frequency. The lag time between the present vibrations and the previous vibrations is one fourth of period of spindle rotation because of four–flute end–mills used in the cutting tests. As a result of cutting tests and considerations, it was concluded that stability of dynamic cutting process could be monitored by the phase angle, with the help of the dominant frequency obtained by the wavelet analysis.
