Patent attributes
An inner rotor (21) is arranged as a motor field, including permanent magnets (25) embedded in an inner rotor core (24) and an inner rotor shaft (26) coupled with the inner rotor core. An outer rotor (22) is arranged as a motor armature, including a hollow armature core (36), plurality of windings (37), two side flanges (38, 39), and an outer rotor shaft (40) coupled with one of the side flanges. The inner rotor is rotatably supported inside the outer rotor, and both rotors are rotatably supported inside a stationary motor enclosure (23). Electric current is conducted to the windings of the armature via brushes (58) and sliprings (59). The interaction between a revolving electromagnetic field of the outer rotor and the permanent magnetic field of the inner rotor propels both rotors to rotate in opposite directions. Two axial fans (82, 83) integrated with the outer rotor side flanges and two axial fans (95, 96) coupled with the inner rotor shaft work in series and produce continuous internal close-loop air circulation between both rotors and between the outer rotor and the motor enclosure, for improving the rate of heat transmission from the rotors to the motor enclosure. If the outer rotor is selectively immobilized, the two inner rotor axial fans produce the internal close-loop air circulation.
