Stator and electric motor using same

A stator comprising:

• a cylindrical stator core;
• a plurality of tooth portions formed along a circumferential direction of the stator core, and
• windings disposed in a plurality of slots formed between the tooth portions and wound around the tooth portions,
• characterized in that:
• the windings are configured by materials having different electrical resistivities, and a material having a low electrical resistivity is copper and a material having a high electrical resistivity is aluminum, and
• a ratio of a sectional area of the windings using aluminum as the material to a sectional area of the windings using copper as the material is within a range in which the ratio can be considered equivalent to a square root of the ratio of the electrical resistivity of aluminum to the electrical resistivity of copper.

An electric motor comprising:

• a cylindrical stator core;
• a plurality of tooth portions formed along a circumferential direction of the stator core,
• windings disposed in a plurality of slots formed between the tooth portions and wound around the tooth portions,
• a rotor that rotates based on a magnetic field generated by the windings, and
• a shaft fixed to the rotor and transmitting a rotational force of the rotor to an external member,
• characterized in that:
• the windings are configured by materials having different electrical resistivities, and
• a ratio of a sectional area of a material having a high electrical resistivity to a sectional area of a material having a low electrical resistivity in the slot is equal to a square root of a ratio of the electrical resistivity of the material having the high electrical resistivity to the electrical resistivity of the material having the low electrical resistivity.

An electric motor comprising:

• a cylindrical stator core;
• a plurality of tooth portions formed along a circumferential direction of the stator core,
• windings disposed in a plurality of slots formed between the tooth portions and wound around the tooth portions,
• a rotor that rotates based on a magnetic field generated by the windings, and
• a shaft fixed to the rotor and transmitting a rotational force of the rotor to an external member,
• characterized in that:
• the windings are configured by materials having different electrical resistivities, and a material having a low electrical resistivity is copper and a material having a high electrical resistivity is aluminum, and
• a ratio of a sectional area of the windings using aluminum as the material to a sectional area of the windings using copper as the material is within a range in which the ratio can be considered equivalent to a square root of the ratio of the electrical resistivity of aluminum to the electrical resistivity of copper.