Online rotor balancing by weight spheres controlled by magnetorheological fluids

In this contribution, a balancing head based on spherical weights suspended in magnetorheological fluid (MRF) is proposed. This system enables an influence on the mass distribution of a machine during its rotation. The principle of operation involves three chambers mounted in a star shape on the rotor, each chamber containing MRF and a balancing sphere. The mass density of the balancing spheres differs from the mass density of the surrounding fluid. If the sphere is deliberately moved within one of the chambers, the difference in mass density results in a change in the mass distribution, which can be utilised to balance the rotor.