Three-phase induction motor and secondary conductor thereof
AssigneeMitsubishi Electric Corporation
InventorsKenta Kaneko, Kazuaki Otsu, Haruyuki Kometani
Life of this patent
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Abstract
A three-phase induction motor includes: a stator having a stator slot having an open slot structure for inserting a formed coil; and a rotor having a rotor slot into which a conductor bar is inserted, the rotor being placed on an inner side of the stator with a clearance between the rotor and the stator. The conductor bar has a polygonal cross-sectional shape having six or more angles, and both end portions of an outer-circumference-side edge surface of the conductor bar are rounded.
Claims18
A three-phase induction motor, comprising:
- a stator having a stator slot having an open slot structure for inserting a formed coil;
- and
- a rotor having a rotor slot into which a secondary conductor is inserted, the rotor being placed on an inner side of the stator with a clearance between the rotor and the stator, the rotor slot having a polygonal cross-sectional shape having six or more angles, wherein
- the secondary conductor has a polygonal cross-sectional shape having six or more angles that is different from the cross-sectional shape of the rotor slot, and both end portions of an outer-circumference-side edge surface of the secondary conductor are rounded,
- a portion of the outer-circumference-side edge surface other than the both end portions makes no contact with the rotor,
- the both end portions make surface contact with a tapered portion formed on an outer circumference side of the rotor slot, and
- when the secondary conductor is inserted in the rotor slot, a slot opening portion is placed on an outer circumferential surface side of the rotor slot and a gap is formed between the slot opening portion and the outer-circumference-side edge surface.
A secondary conductor for use in a three-phase induction motor, the motor comprising:
- a stator having a stator slot having an open slot structure for inserting a formed coil;
- and
- a rotor having a rotor slot and placed on an inner side of the stator with a clearance between the rotor and the stator, the rotor slot having a polygonal cross-sectional shape having six or more angles, the secondary conductor being inserted in the rotor slot so as to configure a part of the three-phase induction motor, wherein
- the secondary conductor has a polygonal cross-sectional shape having six or more angles that is different from the cross-sectional shape of the rotor slot, and both end portions of an outer-circumference-side edge surface of the secondary conductor are rounded,
- a portion of the outer-circumference-side edge surface other than the both end portions makes no contact with the rotor,
- the both end portions make surface contact with a tapered portion formed on an outer circumference side of the rotor slot, and
- when the secondary conductor is inserted in the rotor slot, a slot opening portion is placed on an outer circumferential surface side of the rotor slot and a gap is formed between the slot opening portion and the outer-circumference-side edge surface.
Dependencies are inferred from the claim text.