Sound Noise Generated from Ball Bearing in High Speed Rotation

Abstract

The sound noise generated from ball bearings rotating vertically at high speeds till 900 rps is measured and analyzed under many kinds of supports of the outer races, for instance, with the steel housings and with the plastics. The results are compared with those of the usual researches concerning sound noise at the low speed rotation of about 50 rps, and the change of noise due to the change of the supporting condition of the outer races is studied. At the low speed rotation, the total sound pressure level is lower under the soft support with the plastics than under the hard support with the steel housings, but the state is reversed at the high speed rotation. The main components of frequencies are composed of integral multiples of the rotating frequency as well as the natural frequencies of the outer races, the retainer, the rotor and other parts of the rotating instrument.