Stability high gain and dynamic stiffness servo axis drive system and method

摘要

A high gain and high torsional stiffness servo axis drive system for machine tools is described as providing improved stability. This system includes a servo motor mounted on a base and connected to a C-Axis spindle drive arrangement via a toothed drive belt. A first by-damper is attached to the spindle drive pulley and tuned for damping torsional oscillations of the servo output shaft, belt, and spindle when the system is not fitted with a workpiece. An independent second damper is attached to the driving pulley of the servo motor and tuned for damping torsional oscillations of the entire servo drive system when the system is loaded with a workpiece. The resulting servo axis drive system features improved stiffness and can be adapted to a variety of predetermined loading conditions by convenient retuning of the second damper. At least the second damper is provided as a combination of a damper mass ring attached to the servo motor pulley by a plurality of viscoelastic damping elements. It is contemplated that the damping elements can be easily substituted to retune the system for different loading conditions.