Patent ID: 8269388

Claim:
A rotor assembly comprising: a rotor having opposing first and second ends, a central axis extending generally between the two ends, the central axis being one of collinear with and generally parallel to a reference axis, and a radial surface, the rotor being rotatable about the central axis; at least one electromagnet disposed proximal to and configured to exert magnetic force on a portion of the rotor; and a channeling member disposed generally adjacent to the electromagnet and having a radial surface disposed generally adjacent to the rotor radial surface such that magnetic flux generated by the electromagnet extends generally radially between the electromagnet and the rotor portion and generally axially between the rotor portion and the channeling member so that the magnetic force biases the rotor both radially and axially with respect to the reference axis to maintain the rotor at a desired position with respect to the reference axis; wherein the at least one electromagnet includes two core members spaced apart generally along the reference axis and two coils, each coil being disposed circumferentially about the core member and connectable with a source of electric power such that magnetic flux extends in a generally circuitous path through the two core members, the rotor portion and the channeling member when current flows through the two coils.