Abstract
The ball balancer has been used for the vibration suppression method in rotor system. It has a superior characteristic that the vibration amplitude is reduced to zero by it at the rotational speed range higher than the major critical speed. However, the ball balancer may cause a self-excited vibration when the balls rotate in the disk, and this self-excited vibration results in the large amplitude vibration. In this paper, the occurrence region and vibration characteristics of the self-excited vibration are investigated. The theoretical analysis is performed and a set of the fundamental equations governing the self-excited vibration is obtained. The influences of the parameters, such as, damping of the ball motion, gyro-effect of the system, ball mass, radius of the ball orbit, and the system nonlinearity are explained. As the result, it is shown that the damping of the ball motion and the ball mass have the effect on decreasing the occurrence region of the self excited vibration.
