Patent ID: 7834505

Claim:
A rotary device of a generator or motor comprising: a stator having a hollow portion formed at the inside thereof and a plurality of slots formed to wind coils therearound, each of the plurality of slots being skewed at a predetermined angle; a rotor shaft formed of a nonmagnetic material; a cylindrical rotor body adapted to axially rotate together with the rotor shaft; a plurality of N-polar and S-polar permanent magnet groups insertedly coupled radially along the outside of the center portion of the rotor body in an alternating arrangement; a plurality of permanent magnets insertedly coupled along the inside of the rotor body and arranged on the lines of magnetic force formed by the N-polar and S-polar permanent magnet groups, for increasing magnetic flux; and a rotor adapted to be rotatably inserted into the hollow portion of the stator, wherein the rotor body has an elongated hole extended toward the center portion of the rotor body from a position between each of the N-polar permanent magnet groups and each of the S-polar permanent magnet groups, for preventing the lines of magnetic force generated by the plurality of N-polar and S-polar permanent magnet groups from being distorted, and for preventing the lines of magnetic force formed by the two permanent magnets disposed at one side of the N-polar (or S-polar) permanent magnet group from entering the two permanent magnets disposed at the other side of the N-polar (or S-polar) permanent magnet group, wherein the permanent magnets arranged at the inner side in the plurality of N-polar and S-polar permanent magnet groups have a magnetic force stronger than the permanent magnets arranged at the outer side of the plurality of N-polar and S-polar permanent magnet groups, wherein each of the elongated holes extends radially and is disposed between the center of the rotor body and a corresponding permanent magnet group, and wherein each of the elongated holes has a shape of radially oblong slit having an azimuthal width substantially narrower than a radial length for preventing the lines of magnetic force generated from being distorted around the elongated holes, and for preventing the lines of magnetic force formed by the two permanent magnets disposed at one side of the N-polar (or S-polar) permanent magnet group from entering the two permanent magnets disposed at the other side of the N-polar (or S-polar) permanent magnet group.