Rotary electric machine including a stator coil end cooling construction and rotor with dual fan blades

Patent metadata

Field	Value
Publication number	US-9742242-B2
Application number	US-201214344833-A
Country	US
Kind code	B2
Filing date	Oct 10, 2012
Priority date	Oct 13, 2011
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

In a rotary electric machine, first inclined surfaces that intersect a plane that includes a central axis of a shaft at a predetermined angle are disposed radially outside gaps between coil ends of circumferentially adjacent concentrated winding coils, and cooling air that is blown out from a cooling fan and has flowed radially outward through the gaps between the coil ends is converted into an axially outward flow by the first inclined surfaces.

First claim

The invention claimed is:

1. A rotary electric machine comprising:
a housing including:
a cylindrical member; and
a first end plate that is disposed on a first axial end of said cylindrical member;
a second end plate that is disposed on a second axial end of said cylindrical member;

a rotor that includes a shaft of which two axial end portions are rotatably supported by said first end plate and said second end plate and an annular rotor core that is fitted over and is fixed to said shaft, said rotor being disposed inside said housing;
a first cooling fan that includes blades and is disposed on a first axial end surface of said rotor core;
a stator that includes:
a stator core in which a plurality of teeth are each disposed so as to project radially inward from an inner circumferential wall surface of an annular core back, and are arranged in a row at a predetermined pitch circumferentially; and
a stator coil that is constituted by concentrated winding coils that are wound onto each of said teeth,
said stator being held by said cylindrical member so as to surround said rotor; and

an air channel dividing plate that is disposed between an axial direction of said first end plate and coil ends at a first axial end side of said concentrated winding coils that are positioned radially outside said first cooling fan,
an inner circumferential edge of said air channel dividing plate being radially separated from said shaft, and
a cyclic pathway being formed in which cooling air is blown out from said first cooling fan, flows radially outward along a first axial end surface of said stator core between axial positions of said first axial end surface of said stator core and said air channel dividing plate, and then flows radially inward between axial positions of said air channel dividing plate and said first end plate, and returns to said first cooling fan on an inner circumferential side of said air channel dividing plate,
wherein said rotary electric machine comprises a first air channel converting member that is disposed on said first end surface of said stator core so as to be positioned radially outside a circumferential gap between coil ends at a first axial end side of circumferentially adjacent concentrated winding coils, and that converts said cooling air that is blown out from said first cooling fan and has flowed radially outward along said first axial end surface of said stator core from said circumferential gap between said coil ends at said first axial end side of said circumferentially adjacent concentrated winding coils into an axial flow toward said first end plate, wherein said first air channel converting member has a thickness that varies along a direction parallel to an axis of the shaft and tapers off towards an end portion of said first channel converting member.

2. The rotary electric machine according to claim 1 , further comprising a second air channel converting member that is disposed between said air channel dividing plate and said first end plate so as to face said first air channel converting member axially so as to convert into a radially inward flow said axial flow of said cooling air that is converted into said axial flow toward said first end plate by said first air channel converting member.

3. The rotary electric machine according to claim 1 , further comprising insulating members that include:
a drum portion; and
a pair of flange portions that are formed integrally on two longitudinal ends of said drum portion;
wherein each of said concentrated winding coils is produced by disposing said insulating members on two end surfaces of said stator core such that said drum portions are positioned on end surfaces of said tooth such that longitudinal directions thereof are oriented radially, and said pair of flange portions are positioned on end surfaces of said core back and inner circumferential edges of end surfaces of said tooth, and by winding a conductor wire around said tooth and said drum portions that are disposed on said two ends of said tooth;
wherein said first air channel converting members are formed on two circumferential side portions of said flange portions of said insulating members that are positioned on said end surfaces of said core back;
wherein a third air channel converting member is formed on a portion of said insulating members that faces radially inward from a circumferentially central portion of said flange portions that are positioned on said end surfaces of said core back;
wherein a ventilating groove is formed on a surface of said drum portion so as to extend from a radially inner side to said third air channel converting member; and
wherein said cooling air that is blown out from said first cooling fan and has flowed radially outward between said ventilating grooves and said concentrated winding coils is converted to an axial flow toward said first end plate by said third air channel converting member.

4. The rotary electric machine according to claim 1 , further comprising a connecting board that is manufactured into a ring-shaped flat plate, that is disposed axially outside said concentrated winding coils of said stator, and that connects said concentrated winding coils to configure a predetermined alternating-current winding, said connecting board also functioning as said air channel dividing plate.

5. The rotary electric machine according to claim 1 , wherein a second cooling fan is disposed on a second axial end of said rotor, and the number of blades that are formed on said first cooling fan and said second cooling fan is different.

6. The rotary electric machine according to claim 1 , wherein said blades extend radially outward from said rotor core such that outer circumferential edges thereof are positioned in radial positions between an inner circumferential edge of said stator core and inner circumferential edges of said coil ends at said first axial end side of said concentrated winding coils.

7. The rotary electric machine according to claim 1 , wherein:
said rotor includes:
a spider that includes:
a tubular rotor core holding portion; and
a spider-flange portion that extends radially outward from a first axial end of said rotor core holding portion;

a rotor core that is mounted so as to be fitted over and fixed to said rotor core holding portion;
permanent magnets that are housed in magnet insertion apertures that are each formed so as to pass through an outer circumferential portion of said rotor core so as to have aperture directions in an axial direction so as to be disposed at a predetermined pitch circumferentially;
a rotor core bracing plate that is mounted and fixed to a second axial end of said rotor core holding portion so as to restrict axial movement of said rotor core together with said spider-flange portion; and
said shaft which is mounted so as to be fitted inside and fixed to said rotor core holding portion; and

said spider-flange portion includes said blades to constitute said first cooling fan.

8. The rotary electric machine according to claim 7 , wherein said blades are formed on a surface of said spider-flange portion that faces said rotor core.

9. The rotary electric machine according to claim 7 , wherein the number of said blades is not a multiple of a divisor of the number of said permanent magnets and the number of slots in said stator core.

10. The rotary electric machine according to claim 7 , wherein said blades are formed on a surface of said spider-flange portion on an opposite side from said rotor core.

11. The rotary electric machine according to claim 10 , wherein said blades are formed such that a width thereof widens gradually from an outer circumferential end to an inner

Assignees

• Watanabe Norihiro
• Morita Masao
• Miyama Yoshihiro
• Hazeyama Moriyuki
• Arita Hideaki
• Mitsubishi Electric Corp

Inventors

• Watanabe Norihiro
• Morita Masao
• Miyama Yoshihiro
• Hazeyama Moriyuki
• Arita Hideaki

Classifications

• H02K3/24

  with channels or ducts for cooling medium between the conductors · CPC title

• H02K9/19

  for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil · CPC title

• H02K9/04

  having means for generating a flow of cooling medium · CPC title

• H02K2203/03

  Machines characterised by the wiring boards, i.e. printed circuit boards or similar structures for connecting the winding terminations · CPC title

• H02K9/02

  by ambient air flowing through the machine · CPC title