The effect of anisotropic bearings on dynamics and stability of the Ball-spring autobalancer

In recent years, there has been much interest in the use of automatic dynamic ball balancers to balance the rotors with varying imbalances. An automatic dynamic ball balancer is a device that can automatically compensate the variable imbalances of a rotor in certain working conditions without having to stop the rotating equipment. Ball-spring autobalancer is a new type of automatic ball balancers which has two main advantages over the traditional ones, i.e. it causes the rotor vibration amplitude at the transient state to be small and it has a wider balanced stable region. Bearings are one of the most important mechanical components due to their considerable influence on the dynamic behavior and stability of the rotary systems. In previous studies, the dynamic behavior and stability of the rotor with isotropic bearings equipped with a Ball- spring autobalancer has been analyzed. However in practice, the bearings have generally anisotropic behavior due to manufacturing process. In this study, the dynamics and stability of a rotor with anisotropic bearings equipped with a Ball-spring autobalancer are investigated via the multiple scales method for the first time. The results show that the anisotropic bearings do not impair the main advantages of the Ball-spring autobalancers, and as the anisotropic parameter increases the balanced stable region decreases.