On the Quasi-Static Design of Machine Tool Spindles

The paper simplifies the analysis of the general multi-stepped spindle-bearing system model. Various design parameters are considered with the objective of attaining high static stiffness in the cutting zone. Parameters considered in the study include bearing spacing and stiffness, dimensionless flexural stiffness, number and length of the steps, effect of the driving force and the reaction moment exerted at the central front bearing. The calculations enable optimization (for maximum stiffness) at the chuck for short overhang spindles such as those of lathes. The most effective design parameter is the optimum bearing spacing, demonstrated in the study by evaluating the exact analytical solution of the derived equations.