Abstract
Diagnosis for cylindrical roller bearings was carried out using the compound sensing system which can be simultaneously measured acoustic emission (AE) and vibration signal. At first, in order to count AE event rate, influence of the number of boundary from the bearings to the sensor, and the optimum threshold level were examined. As the results, it was preferred that the threshold level is 2 times of the background without amplitude, and the number of boundary is less than 6. Then, it was possible to detective for damage of bearings by the sensing of AE event count rate and FFT analysis of AE envelope wave.
