Rotating electric machine

Patent metadata

Field	Value
Publication number	US-9343933-B2
Application number	US-201414258169-A
Country	US
Kind code	B2
Filing date	Apr 22, 2014
Priority date	Dec 9, 2013
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

A rotating electric machine includes a rotor including: a rotor core divided into blocks in an axial direction, the blocks being arranged to have a phase angle therebetween in a circumferential direction, the rotor core having magnet through holes arrayed in the circumferential direction and formed in an outer circumferential region; and permanent magnets inserted into the magnet through holes. The magnet through hole includes: a magnet insertion portion into which the permanent magnet is inserted; and a non-magnetic portion provided on an outer side of the magnet insertion portion in the circumferential direction. A bridge portion is formed between the outer circumferential surface and an outer circumferential inner wall of the non-magnetic portion. A bridge angle, which is an angle between both circumferential ends of the bridge portion with a rotation center of the rotor core set as a vertex, is larger than a skew angle.

First claim

What is claimed is:

1. A rotating electric machine comprising a rotor and a stator,
the rotor comprising:
a rotor core divided into a plurality of blocks in an axial direction of the rotor core,
the plurality of blocks being arranged to have a phase angle therebetween in a circumferential direction of the rotor core so that a stepped skew is formed in the rotor core,
the rotor core having a plurality of magnet through holes arrayed in the circumferential direction and formed in an outer circumferential region of the rotor core; and

a plurality of permanent magnets inserted into the plurality of magnet through holes so that a first magnetic pole and a second magnetic pole are formed alternately in the circumferential direction on an outer circumferential surface of the rotor core, and

the stator comprising:
an annular stator core having a plurality of teeth arranged in the circumferential direction with intervals; and
a conductive wire wound around each of the plurality of teeth,

wherein each of the plurality of magnet through holes comprises:
a magnet insertion portion into which each of the plurality of permanent magnets is inserted; and
a non-magnetic portion provided on an outer side of the magnet insertion portion in the circumferential direction, for suppressing sneaking of a magnetic flux from a radially-outer side surface of each of the plurality of permanent magnets to a radially-inner side surface of each of the plurality of permanent magnets,

wherein the non-magnetic portion has an outer circumferential inner wall formed along the outer circumferential surface of the rotor core so that a bridge portion is formed between the outer circumferential surface of the rotor core and the outer circumferential inner wall of the non-magnetic portion,
wherein a bridge angle, which is an angle between both circumferential ends of the bridge portion with a rotation center of the rotor core set as a vertex of the angle, is equal to or larger than a skew angle, which is the phase angle between the plurality of blocks adjacent to each other, and
wherein, in the plurality of blocks that are largest in the phase angle in a rotation direction, a distance between a magnetic pole center-side end of the bridge portion arranged on an advancing side having the first magnetic pole formed in one of the plurality of blocks arranged on a most advancing side, and a magnetic pole center-side end of the bridge portion arranged on a retarding side having the second magnetic pole formed in one of the plurality of blocks arranged on a most retarding side, is equal to or larger than a circumferential width at a distal end of each of the plurality of teeth.

2. A rotating electric machine according to claim 1 ,
wherein a circumferential width of the bridge portion is equal to or larger than a circumferential width at a distal end of each of the plurality of teeth.

3. A rotating electric machine comprising a rotor and a stator,
the rotor comprising:
a rotor core divided into a plurality of blocks in an axial direction of the rotor core,
the plurality of blocks being arranged to have a phase angle therebetween in a circumferential direction of the rotor core so that a stepped skew is formed in the rotor core,
the rotor core having a plurality of magnet through holes arrayed in the circumferential direction and formed in an outer circumferential region of the rotor core; and

a plurality of permanent magnets inserted into the plurality of magnet through holes so that a first magnetic pole and a second magnetic pole are formed alternately in the circumferential direction on an outer circumferential surface of the rotor core, and

the stator comprising:
an annular stator core having a plurality of teeth arranged in the circumferential direction with intervals; and
a conductive wire wound around each of the plurality of teeth,

wherein each of the plurality of magnet through holes comprises:
a magnet insertion portion into which each of the plurality of permanent magnets is inserted; and
a non-magnetic portion provided on an outer side of the magnet insertion portion in the circumferential direction, for suppressing sneaking of a magnetic flux from a radially-outer side surface of each of the plurality of permanent magnets to a radially-inner side surface of each of the plurality of permanent magnets,

wherein the non-magnetic portion has an outer circumferential inner wall formed along the outer circumferential surface of the rotor core so that a bridge portion is formed between the outer circumferential surface of the rotor core and the outer circumferential inner wall of the non-magnetic portion,
wherein a bridge angle, which is an angle between both circumferential ends of the bridge portion with a rotation center of the rotor core set as a vertex of the angle, is equal to or larger than a skew angle, which is the phase angle between the plurality of blocks adjacent to each other, and
wherein, when a first block of the plurality of blocks is adjacent to a second block of the plurality of blocks and the first block and the second block are laminated on each other in the axial direction, a dimension in the circumferential direction of an axially overlapping part of the bridge portion of the first block and the bridge portion of the second block is equal to or larger than a circumferential width at a distal end of each of the plurality of teeth.

4. A rotating electric machine according to claim 1 , wherein a coil of the stator is formed by distributed winding.

5. A rotating electric machine according to claim 1 , wherein one of the plurality of blocks, which is arranged on a most retarding side in a rotation direction, and one of the plurality of blocks, which is arranged on a most advancing side in the rotation direction, are arranged at axial ends of the rotor core.

6. A rotating electric machine according to claim 1 , wherein, when maximum torque of a power running operation is larger than maximum torque of a regenerative operation, one of the plurality of blocks, which is arranged on a most retarding side in a rotation direction, is arranged at an axial end of the rotor core.

7. A rotating electric machine according to claim 1 , wherein, when maximum torque of a regenerative operation is larger than maximum torque of a power running operation, one of the plurality of blocks, which is arranged on a most advancing side in a rotation direction, is arranged at an axial end of the rotor core.

Assignees

• Mitsubishi Electric Corp

Inventors

• Isoda Hitoshi
• Inoue Masaya
• Nishimura Shinji
• Hazeyama Moriyuki
• Tachibana Tomoya

Classifications

• H02K2201/06

  Magnetic cores, or permanent magnets characterised by their skew · CPC title

• H02K1/2766 Primary

  having a flux concentration effect · CPC title

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title