An Approach to Acquire Vibration Signals for Gear Fault Detection

The vibration transmission path introduces complexity to the existing modulated vibration signals making gear fault diagnosis difficult. This manuscript proposes a new arrangement to acquire gear vibrations thereby highlighting the effect of transmission path on gear vibrations. In proposed arrangement, an accelerometer is mounted on a gear, near to the location of gear meshing, such that the vibrations of non-rotating parts will be least recorded. The approach of acquiring gear vibrations is demonstrated by an experimental investigation, and an attempt to detect gear faults has been made. The effectiveness of the proposed approach is shown by comparing the responses of two accelometers located inside and outside of gearbox. Further, signal-to-noise ratio (SNR) was computed for all the recorded signals to analyze the signal strength of gear vibrations. It was noted that accelerometer mounted internally depicts the faults more prominently as compared to the accelometer mounted conventionally. Increased SNR values and increased amplitude of sidebands around gear mesh frequency and its harmonics depicts the capability of the proposed approach. Furthermore, FM0 and sideband energy ratio were used to analyze the signals statistically, validating the effectiveness of proposed new approach.