Vibration Characteristics and Machining Performance of a Milling Spindle System with Electro-Magnetic Bearings

Abstract

To understand the, vibration characteristics and the machining performance of a phetoiype milling spindle system with electromagnetic bearings, computational structure dynamics analysis and excitation test have been conducted as well as high speed (36000rpm) end milling wrought aluminium alloys. It has been known that the maximu speed of the tested spindle system is limited by a natural frequency of tie spindle identified as about 800Hz, and also the stiffness cf the spindle needs to be increased for higher speed rotation as well as improved machining performance using wider variety of cutting tools. Based on the computational analysis, alternative spindle designs have been proposed.