Joint Amplitude and Frequency Demodulation Analysis Based on Variational Mode Decomposition for Multifault Diagnosis of a Multistage Reducer

Figure 4

Physical diagram of faulty sun and spur gears: (a) normal sun gear, (b) local fault (broken tooth) of sun gear, (c) distributed fault (uniform wear) of sun gear, (d) normal spur gear, (e) local fault (broken tooth) of spur gear, and (f) distributed fault (uniform wear) of spur gear.

(a)

(b)

(c)

(d)

(e)

(f)