Non-linear dynamics of an unbalanced machine-tool spindle system supported by ball bearings

摘要

In this article, an eight-degree-of-freedom (eight-DOF) model is presented to study the dynamic characteristics of a machine-tool spindle system supported by ball bearings. In this model, the effects of bearing clearance, spindle speed, and cutting conditions are studied. To study the dynamic characteristics of the system, numerical simulations are carried out. Results are presented in the form of bifurcation diagrams, Poincaré maps, and phase trajectories. These results show that the regions of periodic, subharmonic, and chaotic behaviour are strongly dependent on the bearing clearance and spindle speed. Apart from the effects of these two on the dynamic behaviour, the cutting conditions also play a significant role in determining the dynamic behaviour of the machine-tool spindle system.