Electric motor with rotating body and electric device provided therewith

摘要

Provided is an electric motor driven by an inverter of PWM method, and devised to retard electrolytic corrosion in a bearing. A rotating body of a rotor comprises an outer iron core configuring an outer peripheral portion of the rotating body, an inner iron core configuring an inner peripheral portion connected to a shaft, a dielectric layer disposed between the outer iron core and the inner iron core, a plurality of insertion holes penetrating the outer iron core in the axial direction, and permanent magnets inserted individually in the plurality of insertion holes. It thus becomes possible to increase impedance of the rotor side (inner ring side of bearing) to approximate it to impedance of the stator side (outer ring side of the bearing) to thereby bring high frequency potentials balanced between the inner ring side and the outer ring side of the bearing, so as to provide the electric motor that retards electrolytic corrosion liable to occur in the bearing, and an electric device equipped with the same.

主权项

1. An electric motor comprising:
a stator having a stator core and a coil wound around the stator core; a rotor having a rotating body positioned inside the stator and a shaft connected to the rotating body in a manner to penetrate through the center of the rotating body; a bearing rotatably supporting the shaft; and a bracket fixing the bearing; wherein the rotating body comprises:
an outer iron core configuring an outer peripheral portion of the rotating body and comprising a plurality of insertion holes in an axial direction;an inner iron core placed radially inside the outer iron core and configuring an inner peripheral portion connected to the shaft;a dielectric layer disposed radially inside the outer iron core and radially outside the inner iron core, wherein the dielectric layer is formed of insulating resin so as to continuously surround the inner iron core and fixes the outer and inner cores together while electrically insulating one core from the other; andpermanent magnets inserted individually in the plurality of insertion holes.