Patent ID: 8115364

Claim:
A permanent magnet generator comprising: a generator shaft; at least three rotors, wherein each rotor is secured to the generator shaft, each rotor comprises a plate-shaped structure having a permanent magnet secured therewith, and each plate-shaped structure is disposed in the longitudinal direction of the generator shaft; and a stator, the stator comprising a plate-shaped structure having a stator coil of a wound copper wire, wherein the stator coil is connected together in series in a single-phase, or connected together in series in a three-phase, and wherein the stator is disposed in at least two gaps formed by the rotors and is separated from the generator shaft; wherein the rotors and the stator are disposed alternately with a total of not less than five stages in the longitudinal direction of the generator shaft; wherein the polarity of the permanent magnets is aligned in an axial direction with opposite polarities of the permanent magnets directed toward each other from opposite sides of the same stator disposed in the gap therebetween such that magnetic lines of force representing the sum of the magneto-motive forces emanated from each of the magnets of all of the rotors pass through the magnets and gaps, enhancing each other's magnetic fields and strengthening the magnetic field in the gaps; and wherein the rotors located at both ends have the permanent magnet attached to a plate-shaped yoke on a side which faces the stator, the yoke comprising magnetic material, wherein the magnetic flux generated from the magnetic poles can reflux through the plate-shaped yokes, thereby reducing a magnetic leakage from the rotors at the both ends.