Design And Research On Fully Automated Balancing Machines

With the development of science and technology, rotating machine is applicated more and more widely in the engineering. Due to the accuracy of manufacturing and the effect of wear and tear, the phenomenon of unbalance will gradually appear in rotating machine after leaving factory and long-term using. For motor rotors, unbalancing phenomena is mainly manifested as mechanical vibration and large noise. Long time running in unblancing state for rotating machine will not only damage its mechanical life, but also causes other safety problems, which is needed to be solved. To solve this unbalancing phenomena, balancing technology is the unique method. For this reason, this method attracts the attention of engineering. According to the requirement of actual production, the balancing machine is made up of two parts—the testing device of unbalancing signals and the calibration device, which is more and more automatic and high-accuracy. It’s significant for human production to develop balancing machine. In the research of automated balancing machine, digital filtering technique of signals, measurement of unbalacing signal’s phase and amplitude, communication of inner system, attract attentions of engineers. This article mainly tells about the digital signal processing algorithm of unbalancing vibration signal, and the communicating protocol of balancing machine.After studying on signals processing theory, this article puts up a new method to process unblancing vibrational signal in the complicated situation told above. First,we uses elliptic band-pass digital filter to process original signal and then get the fundamental frequency signal; Second, we use zero phase-shift digital filter to compensate the phase change; Third, we use ap FFT to analyse the filted sequence and get the predicting value of phase and amplitude. The elliptic band-pass digital filter has excellent pass-band selectivity and is easier to realize; The zero phase-shift digital filter can fully compensates the phase change theoretically; The ap FFT theory is of excellent performance, which will solve the problems of sidelobe jamming and spectrum leakage due to non-periodic sampling in traditional FFT and be able to get more accurate predicted value of vibrational signal’s frequency, initial phase and amplitude. The predicted initial phase is the unbalancing position in the rotor, and the predicted amplitude is the amount of unbalance. In the whole working process, we use MODBUS communicating protocol to coordinate every part’s work in the balancing machine system and ensure the reliable operation of this system. Our experiments prove that, digital filtering technique and ap FFT algorithm is able to filter out interference and define the phase and amplitude of the unbalancing vibration signal. Through the MODBUS protocol, communication is stable in the balancing machine system and all parts of devices coordinate well.