Axial gap rotary electric machine

Patent metadata

Field	Value
Publication number	US-10566876-B2
Application number	US-201616078298-A
Country	US
Kind code	B2
Filing date	Feb 25, 2016
Priority date	Feb 25, 2016
Publication date	Feb 18, 2020
Grant date	Feb 18, 2020

Abstract

To significantly improve a heat dissipation property of an axial gap rotary electric machine within a size necessary for configuring a motor. In an axial gap rotary electric machine comprising a stator and a rotor in an axial direction, the stator has a plurality of stator cores arranged in a circumferential direction and coils wound around the stator cores, and a heat pipe obtained by filling an inside of a metal hollow pipe with a refrigerant is arranged in a gap between adjacent coils formed in an outer diameter portion of the stator in a radial direction and a housing with a necessary insulation distance between the coils and the heat pipe. The heat pipe extends in a direction of a rotation axis and an opposite output side, and is in contact with a heat dissipating fin outside an end bracket on the opposite output side.

First claim

The invention claimed is:

1. An axial gap rotary electric machine comprising a stator and a rotor in an axial direction, wherein
the stator has a plurality of stator cores arranged in a circumferential direction and coils wound around the stator cores, and
a heat pipe obtained by filling an inside of a metal hollow pipe with a refrigerant is arranged in a gap between adjacent coils formed in an outer diameter portion of the stator in a radial direction and a housing with a necessary insulation distance between the coils and the heat pipe.

2. The axial gap rotary electric machine according to claim 1 , wherein
the heat pipe extends in a direction of a rotation axis and an opposite output side and is in contact with and fixed to an end bracket on the opposite output side.

3. The axial gap rotary electric machine according to claim 1 , wherein
the heat pipe extends in a direction of a rotation axis and an opposite output side and is in contact with a heat dissipating fin outside an end bracket on the opposite output side.

4. The axial gap rotary electric machine according to claim 3 , wherein
the heat dissipating fin has a disc shape and has a hole into which the heat pipe is fitted opened in the circumferential direction, and
the heat pipe is in contact with and fixed to the hole.

5. The axial gap rotary electric machine according to claim 4 , wherein
the disc-shaped heat dissipating fin has a flat plate structure in which a metal plate is punched into a disc shape.

6. The axial gap rotary electric machine according to claim 4 , wherein
the disc-shaped heat dissipating fin has a spiral structure in which a thin metal plate is edgewisely wound into a disc shape.

7. The axial gap rotary electric machine according to claim 4 , wherein
the disc-shaped heat dissipating fin has a structure in which strip-shaped metal plates are joined together.

8. The axial gap rotary electric machine according to claim 4 , wherein
the disc-shaped heat dissipating fin is configured using a metal block, and irregularities for increasing a surface area are formed on a surface thereof.

9. The axial gap rotary electric machine according to claim 1 , wherein
one stator and two rotors on both sides of the stator are provided in the axial direction, and
at least the stator core, the coil, and the heat pipe are molded with a molding resin.

10. The axial gap rotary electric machine according to claim 1 , wherein
the heat pipe is arranged only between adjacent coils having an identical phase and different current directions.

11. The axial gap rotary electric machine according to claim 1 , wherein
the heat pipe is in contact with and fixed to a heat dissipating plate which is arranged at an end portion of a resin bobbin of the stator core and has a grounding function.

12. The axial gap rotary electric machine according to claim 1 , wherein
the housing is made of a non-magnetic and non-conductive material, and
at least the housing, the stator core, the coil, and the heat pipe are molded with a molding resin.

13. The axial gap rotary electric machine according to claim 1 , wherein
a heat sink for cooling a power element of a rotary electric machine control device is arranged at the end bracket on the opposite output side,
a control board of the rotary electric machine control device is further arranged on an outer portion of the heat sink, and
the heat pipe is in contact with and fixed to the heat sink.

14. The axial gap rotary electric machine according to claim 1 , wherein
a control board of a rotary electric machine control device is arranged at the end bracket on the opposite output side,
a heat sink for cooling a power element of the rotary electric machine control device is further arranged on an outer portion of the heat sink, and
the heat pipe is in contact with and fixed to the heat sink.

15. The axial gap rotary electric machine according to claim 1 , wherein
a pump is integrally attached to an output shaft side of the rotary electric machine, and
the heat pipe is extended to a pump chamber of the pump.

Assignees

• Hitachi Ltd

Inventors

• Enomoto Yuji
• Tokoi Hirooki
• Sakurai Naoki
• Tanie Hisashi
• Deguchi Kenta

Classifications

• F28D2021/004

  for engine or machine cooling systems · CPC title

• F04D13/0666

  the motor being of the plane gap type · CPC title

• H02K5/18

  with ribs or fins for improving heat transfer · CPC title

• H02K9/04

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

• H02K9/14

  wherein gaseous cooling medium circulates between the machine casing and a surrounding mantle · CPC title