Patent ID: 7880355

Claim:
An electromagnetically variable transmission for transferring power between a pair of independently rotating shafts, comprising: a hollow cylindrical outer rotor portion and a cylindrical inner rotor portion, the inner rotor being disposed within a center aperture of the outer rotor portion and independently rotatable within the outer rotor portion, and the outer rotor independently rotatable circumferentially about the inner rotor portion; a first one of the outer rotor portion and the inner rotor portion having a plurality of permanent magnets pairs spaced about a first surface, the magnets being configured in pairs and facing an air gap, the air gap disposed between the outer rotor portion and the inner rotor portion; an other one of the outer and inner rotor portions having a plurality of slots spaced about a magnetically permeable core portion, at least some of the slots including windings embedded therein, the windings arranged in pole pairs such that each pole pair corresponds to a permanent magnet pair of the first one of the outer rotor portion and the inner rotor portion; the outer rotor portion and the inner rotor portion being simultaneously rotatable in one direction; and at least one auxiliary coil for powering a torque control circuit, the torque control circuit including a power supply, a controller portion and at least one power switch, the controller portion configured to operate the power switch for switching a circulating current in at least one of the windings for controlling the mechanical power transfer; wherein, in response to co-rotation of the outer rotor portion and the inner rotor portion, a magnetic flux path is generated between the plurality of permanent magnet pairs, the air gap and the outer and inner rotor portion cores, the magnetic flux path inducing electrical power in the windings and causing mechanical power to be transferred between the inner rotor portion and the outer rotor portion.