Electric motor with integrated cooling system

Patent metadata

Field	Value
Publication number	US-12424897-B2
Application number	US-202117801156-A
Country	US
Kind code	B2
Filing date	Feb 19, 2021
Priority date	Feb 21, 2020
Publication date	Sep 23, 2025
Grant date	Sep 23, 2025

Abstract

An axial flux electric can include a motor assembly including a motor shaft, a stator assembly, and a rotor assembly. The stator assembly can include a plurality of stator cores about which a wire coil is wound, wherein one or more of the stator cores includes a stator body with an internal fluid passageway for receiving a cooling fluid.

First claim

What is claimed is:

1. An electric motor assembly comprising:
a) a motor shaft, a stator assembly, and a rotor assembly;
b) a cooling jacket surrounding the stator assembly, the cooling jacket including:
(i) an inner wall facing radially inwardly towards the stator assembly and an opposite outer wall facing radially outwardly;
(ii) a circumferential first internal fluid passageway for allowing a cooling fluid to be pumped through an interior of the cooling jacket, the circumferential first internal fluid passageway being disposed between the inner and outer walls and extending between an inlet and an outlet; and

c) a first end plate covering and in contact with at least a portion of a first end of the stator assembly, the first end plate including a second internal fluid passageway in fluid communication with the circumferential first internal fluid passageway for allowing the cooling fluid to be pumped through an interior of the first end plate, wherein the first end plate is separate from the stator assembly and located between the stator assembly and magnets associated with the electric motor assembly,
wherein the electric motor assembly is an axial flux electric motor assembly.

2. The electric motor assembly of claim 1 , wherein the second internal fluid passageway includes a plurality of internal passageways.

3. The electric motor assembly of claim 1 , wherein the first end plate is in direct contact with an end face of one or more stator cores associated with the stator assembly.

4. The electric motor assembly of claim 1 , wherein the second internal fluid passageway is in fluid communication with the circumferential first internal fluid passageway at a plurality of connection points.

5. The electric motor assembly of claim 1 , wherein the first end plate and the cooling jacket are formed from the same type of material.

6. The electric motor assembly of claim 1 , wherein the first end plate and the cooling jacket are formed from different types of materials.

7. The electric motor assembly of claim 1 , wherein the electric motor assembly further includes a pump for delivering the cooling fluid to the circumferential first internal fluid passageway.

8. The electric motor assembly of claim 7 , wherein the pump is driven by the motor shaft.

9. A cooling system for an electric motor assembly, the cooling system comprising:
a) a cooling jacket for surrounding a stator assembly, the cooling jacket including:
(i) an inner wall facing radially inwardly and an opposite outer wall facing radially outwardly;
(ii) a circumferential first internal fluid passageway for allowing a cooling fluid to be pumped through an interior of the cooling jacket, the circumferential first internal fluid passageway being disposed between the inner and outer walls and extending between an inlet and an outlet; and

b) a first end plate configured to cover and be in contact with at least a portion of the stator assembly, the first end plate including a second internal fluid passageway in fluid communication with the circumferential first internal fluid passageway for allowing the cooling fluid to be pumped through an interior of the first end plate, wherein the first end plate is perpendicular to a longitudinal axis of the cooling jacket and the first end plate is a separate component from the cooling jacket, the first end plate being attached to the cooling jacket at a radial inward end and a radial outward end of the first end plate, and
c) wherein the circumferential first internal fluid passageway is fully enclosed in the cooling jacket, and the second internal fluid passageway is fully enclosed within the first end plate, wherein the electric motor assembly is an axial flux electric motor assembly.

10. The cooling system of claim 9 , wherein the second internal fluid passageway includes a plurality of internal passageways.

11. The cooling system of claim 9 , wherein the second internal fluid passageway is in fluid communication with the circumferential first internal fluid passageway at a plurality of connection points.

12. The cooling system of claim 9 , wherein the first end plate and the cooling jacket are formed from the same type of material.

13. The cooling system of claim 9 , wherein the first end plate and the cooling jacket are formed from different types of materials.

14. A method of cooling a stator assembly of an electric motor assembly, the method comprising:
a) delivering and returning a cooling fluid to a cooling jacket surrounding the stator assembly, wherein the cooling jacket comprises:
(i) an inner wall facing radially inwardly towards the stator assembly and an opposite outer wall facing radially outwardly;
(ii) a circumferential first internal fluid passageway for allowing a cooling fluid to be pumped through an interior of the cooling jacket, the circumferential first internal fluid passageway being disposed between the inner and outer walls and extending between an inlet and an outlet; and

b) delivering and returning the cooling fluid to an end plate in direct contact with an end face of the stator assembly such that that cooling is provided to the stator assembly at least at two sides of the stator assembly, wherein the end plate is separate from the stator assembly and located between the stator assembly and magnets associated with the electric motor assembly, wherein the electric motor assembly is an axial flux electric motor assembly.

15. The method of claim 14 , wherein the delivering steps include directing the cooling fluid from the circumferential first internal fluid passageway of the cooling jacket to and from internal passageways of the end plate.

16. The method of claim 14 , wherein the delivering steps are performed with a pump.

17. The method of claim 16 , wherein the delivering steps are performed with a pump driven by the electric motor assembly.

18. The method of claim 14 , wherein the cooling fluid is one of oil, glycol, and water.

19. An electric motor assembly comprising:
a) a motor shaft, a stator assembly, and a rotor assembly, wherein the stator assembly comprises a plurality of stator cores, each of the stator cores comprising a core body extending along a core axis between first and second opposite axial ends and wire coils wound about the core body;
b) a cooling jacket surrounding the stator assembly, the cooling jacket including:
(i) an inner wall facing radially inwardly towards the stator assembly and an opposite outer wall facing radially outwardly;
(ii) a circumferential first internal fluid passageway for allowing a cooling fluid to be pumped through an interior of the cooling jacket, the circumferential first internal fluid passageway being disposed between the inner and outer walls and extending between an inlet and an outlet; and

c) a first end plate covering and in contact with at least the first axial end of at least one of the stator cores, the first end plate including a second internal fluid passageway in fluid communication with the circumferential first internal fluid passageway for allowing the cooling fluid to be pumped through an interior of the first end plate, wherein the first end plate is located adjacent to and between the first axial end of at least one of the stator cores and magnets associated with the electric motor assembly, wherein the first end plate and the stator cores are separate components,
wherein the electric motor assembly is an axial flux electric motor assembly.

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Goykhman Mikhail
• Baronian Armen
• Suntharalingam Piranavan
• Wang Hongbin

Classifications

• H02K16/02

  Machines with one stator and two {or more} rotors · CPC title

• H02K9/197

  in which the rotor or stator space is fluid-tight, e.g. to provide for different cooling media for rotor and stator · CPC title

• H02K1/20

  with channels or ducts for flow of cooling medium · CPC title

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title

• H02K3/24

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