Patent attributes
Correcting unbalance with regard to rotors (11, 101) and shafts is important in order to improve performance of those rotors (11, 101) or shafts within a practical machine or engine. Previously, result orientated iterative balancing of the rotor or shaft has been achieved in which mass has been added or possibly intrusive and distorted adjustments in drag and stiffness presented through bearings or alteration of the rotor (11, 101) itself have been utilised to improve rotor balance performance. In the present invention, a dynamic bearing 13 is utilised in order to provide force components with some components in phase with rotor deflection in order to simulate negative stiffness and/or some force components in phase with rotor velocity in order to simulate negative drag upon the rotor (11, 101). In such circumstances, a more accurate determination of rotor unbalance is achieved to enable known techniques of perturbed boundary condition analysis for balance correction to be implemented more accurately.
