PURPOSE: To prevent iron powder, etc., brought into existence by the cutting of a claw type field iron core after incorporation of a rotor from adhering to this claw type field iron core by the magnetic force of a permanent magnet, and being carried into the stator of a dynamo-electric machine, and causing nonconformity such as rotation trouble.
CONSTITUTION: A rotor, which has an unmagnetized permanent magnet 4 interposed in the space between the magnetic poles in circumferential direction between claw-shaped magnetic poles 21 and 31 and has claw-type magnetic iron cores 2 and 3, is set to a rotary shaft 1, and after completion of manufacture of the rotor, the unmagnetized permanent magnet 4 is magnetized. Hereby, even if the claw-type magnetic iron cores 2 and 3 are cut for adjustment of the rotation balance at manufacture or setting of the rotor, fine iron powder, etc., hard to remove never adhere to the rotor, so this fin iron powder can be prevented from scattering during the rotation of the rotor and biting in the sliding section and causing rotation trouble.
HOTTA TOSHIAKI
SHIMIZU MAKI
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