Spur gearbox mixed fault detection using vibration envelope and motor stator current signatures analysis

Vibration analysis is the most used technique for gearbox fault diagnosis based on gear meshing frequency (GMF) magnitude tracking. The originality of this paper is illustrated in two steps. The meshing between two damaged teeth repeating to the Hunting tooth frequency (HTF) is clearly detected by performing spectral analysis to vibration envelope signal and the motor stator current, unlike the confirmation of [1][2] that this frequency is very low and cannot be measurable. In second step, gearbox input shaft break was predicted by the GMF harmonics magnitude comparison.