Studies on the Vibration and Sound of Defective Rolling Bearings : First Report : Vibration of Ball Bearings with One Defect

An investigation was undertaken with a view to establishing a procedure for diagnosing rolling bearings for defects from their vibration and sound. In the present investigation the vibration and sound of a rolling bearing with one dent on the race surface of the inner or outer ring or on the ball surface were studied. When the inner ring was caused to rotate at a constant speed under a given thrust load applied to the outer ring, the outer ring radial vibration velocity was determined by a moving coil type converter. Using the data so obtained, vibration waveforms were observed, peak vibration pulses measured, and real time frequencies of the vibration analyzed by Fast Fourier Transform analyzer. As a result, the fundamental characteristics of ball bearings having one defect were clarified, and a method by which to locate the defect and determine its size was established.