On the Issue of Motion of Compensating Masses of an Automatic Balancing Device in Rotary Machines with a Horizontal Axis of Rotation

In mechanical engineering, including transport, rotary machines with a horizontal, vertical or inclined axis of rotation are widely used. They have an imbalance that causes vibration during their operation. The use of automatic balancing devices (ABD) can reduce the imbalance of unbalanced rotor systems operating in the super resonance velocity range. However, when accelerating the compensating masses in the rotor-ABD system, a side mode, different from the auto-balancing mode, may occur. In this paper, based on the mathematical model of a horizontal rotor with an ABD, the possible modes of motion of compensating masses are considered and the attraction regions of the main auto-balancing mode are constructed depending on the value of the viscous friction coefficient in the ABD. It is shown that at the decrease of the coefficient of viscous friction in the ABD, the attraction region of the auto-balancing mode decreases, while the rotor system switches to another stable mode.