(1) Failure caused by gear manufacturing and installation errors. Errors in the gear manufacturing process or errors in the assembly process reduce the gear meshing accuracy, which leads to increased gear vibration and noise, and increases the failure rate of the gear. The frequency spectrum is shown as the meshing frequency and its Changes in the amplitude of each harmonic.
(2) A fault caused by the inherent movement of the gear itself (working environment). During the gear meshing process, the continuous impact of the tooth and the tooth causes the gear to generate forced vibration and noise, which is shown as the meshing frequency of the gear on the spectrogram.
(3) Gear surface damage failure, tooth surface wear, gear due to tooth surface peeling, strain and other defects developed to a certain extent, every time the gear rotates, the rings will collide with each other once, resulting in an obvious impact phenomenon. Each impact is equivalent For one pulse excitation, the impulse response function is the inherent damping vibration of the gear, which constitutes a periodic higher frequency shock vibration signal. The cycle period is the rotation period of the shaft, and the damping vibration frequency is the natural frequency of the gear. Tooth surface pitting, tooth chipping, gear meshing process, especially because of gear wear, meshing vibration will occur when the backlash increases, and the vibration frequency is the gear meshing frequency.
(4) The shaft is bent. When the rotating shaft is severely bent, there will usually be obvious shock vibrations at a certain time interval in the time domain, and the number of sidebands is large and dense.
