Noise of Ball Bearing : (3rd Report, Case of Fitted Ball Bearing)

The noise of the ball bearing can be divided into two cases ; one is the case of the simple ball bearing, the other is the case of the fitted one. However, the noise of the latter case has not been researched systematically. So, the auther measured the noise of three kinds of the fitted ball bearings, analyzed about the peak values of the frequency spectrums, and obtained the results as follows : -(1) The noise of a fitted ball bearing has the frequencies above 1 kc/s. The frequencies of the noise do not change at many rotating speeds, but the sound pressure level increases with the rotating speed. (2) The principal noise of a fitted ball bearing is due to the vibrations of the race ring, and the other noise is due to the vibrations of the cage. (3) The noise of a fitted ball bearing and the noise of a simple one are identical in essence.