Diagnostics Cracks in Gears with Wavelet Analysis

摘要

A crack in the tooth root, which is the least desirable damage caused to gear units,often leads to failure of gear unit operation. A possible damage can be identifiedby monitoring vibrations. Time signals were obtained by experiments.Amplitudes of time signal vibration are, by frequency analysis, presented aboveall as a function of frequencies in spectrum using hybrid procedure fordetermining the level of non-stationarity of operating conditions primarily ofrotational frequency. A non-stationary signal was analysed as well, using thefamily of Time Frequency Analysis tools, including Wavelets and Joint TimeFrequency Analyses. Wavelet analysis is suitable primarily for non-stationaryphenomena with local changes. The purpose was to obtain the location of thecrack, i.e. to identify the tooth. Typical spectrogram and scalogram patterns resultfrom reactions to faults or damages; they indicate the presence of faults ordamages in a very reliable way.