An Online Automatic Balancing System to Actively Reduce Vibration of Machine Tool Motorized Spindle

Mass imbalance is one of main vibration sources for rotating machine tool spindle, which has many negative effects on spindle bearing and work-piece surface. In order to reduce these harmful effects, an online automatic balancing system is investigated in this paper. The system proposed is composed of sensor, electromagnetic ring balancer and active controller. The electromagnetic ring balancer uses an annular coil to generate the pulsing drive magnetic field and uses the counterweight plate to obtain the required correction mass. When the spindle rotates, if unbalance occurs the proposed balancer will be driven to reach the predetermined angular position under the electromagnetic field to then realize balance, the balanced position can be determined according to the measured signals and the adaptive influence coefficient method. The new single-plane self-balancing motorized spindle and DSP-based controller were developed to validate design of the proposed online active balancing system. The experimental results show that the developed balancing system is effective for vibration suppression of rigid spindle.Copyright © 2014 by ASME