Effects of Rolling Friction on Ball Positioning for an Automatic Ball Balancer

This paper presents a theoretical and experimental study on the effects of rolling friction between balls and the racer on ball positioning for an automatic ball balancer (ABB). The performance of an ABB, which is characterized by residual vibration of the rotor, relies heavily on balls’ positions. However, the magnitude of rolling friction determines the ball position of the balancing system, which in turn affects the performance of the ABB. In this study, a set of ball balancers are fabricated including ceramic balls and the associated PTFE and ceramic ball races for the purpose of investigating the validity of the mathematical model of the rolling friction. The driving-force equation associated with the dynamic equations of motion of the balls is developed to determine the ball positions as well as the performance of the balancing system. Two sets of experimental apparatus are constructed. One is aimed to verify the mathematical model of the rolling friction of the ball balancer. The other applies an optical-disc drive system together with a high-speed camera to record the ball positions and verify the results obtained from computer simulation.