Experimental Method to Evaluate Unbalance Vibration for Machine Tool Spindle Integrated with Automatic Balancer

Abstract

Unbalance is one of the main vibration sources of rotating machinery. Study on the response of unbalance is important for the machine tool spindle dynamic performance evaluation and balancing technology. How to simulate the unbalance automatic generation and how to effectively analyze the unbalance vibration signal are two main problems. In this paper, an electromagnetic balancer is used to act as the unbalance generator to imitate the tool unbalance during machine tool operation. An integrated spindle with the balancer is developed and the acceleration and displacement sensors are applied to pick up the unbalance vibration. The filtering, linear FFT and averaging are applied to extract the fundamental component from the original signal. The displacement peak-peak value and acceleration peak value are chosen as the characteristic parameter evaluating unbalance response and the shaft orbit is adopted to recognize unbalance intuitively. The experimental results show that the unbalance simulation and signal analysis method are feasible and effective.