Axial flux rotor and axial flux electric machine

Patent metadata

Field	Value
Publication number	US-10916984-B2
Application number	US-201815936978-A
Country	US
Kind code	B2
Filing date	Mar 27, 2018
Priority date	Mar 27, 2018
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

An axial flux rotor for use in a motor with a stator is provided. The rotor includes a body including an outer periphery defined by outside radius OR. The body further has a central opening defined by inner radius IR and a plurality N of rotor poles defining an axis of rotation of the body. The body has first and second opposed faces. The rotor also includes a plurality of spaced apart axially imbedded magnets extending from the first face. At least one of the axially imbedded magnets has a minimum depth defined by defined by the equation
D min = π * ( OR + IR ) 2 * N * BrA * BrS ,
wherein BrS is the Remanent Flux Density of Surface Mounted Magnet, wherein OR is the outside radius of the body, wherein IR is the inner radius of the body, wherein N is the number of rotor poles, and wherein BrA is the Remanent Flux Density of Axially Imbedded Magnet.

First claim

What is claimed is:

1. An axial flux rotor for use in a motor with a stator, said rotor comprising:
a body having an outer periphery defined by an outside radius OR, the body further has a central opening defined by an inner radius IR and a number N of rotor poles defining an axis of rotation thereof, said body having first and second opposed faces; and
a plurality of spaced apart magnets extending from the first face, at least one of said magnets having a minimum length D min defined by

D
min

=

π
*

(

OR
+
IR

)

*
BrS

2
*
N
*
BrA

,

wherein BrS is Remnant Flux Density of a Surface Mounted Magnet, wherein OR is the outside radius of the body, wherein IR is the inner radius of the body, wherein N is the number of rotor poles, and wherein BrA is Remnant Flux Density of an Axially Imbedded Magnet.

2. The axial flux rotor of claim 1 :
wherein said body defining a plurality of pockets formed in first face of said body, said body comprising a plurality of overlaid layers; and
wherein each of said plurality of magnets is matingly fitted to one of said plurality of pockets.

3. The axial flux rotor of claim 1 , wherein said body comprises a plurality of overlaid layers.

4. The axial flux rotor of claim 2 , wherein at least one of the plurality of pockets has a trapezoidal shape.

5. The axial flux rotor of claim 2 , wherein at least one of the plurality of pockets has a rectangular shape.

6. The axial flux rotor of claim 1 , wherein said body comprises a plurality of components connectable by a bonding material.

7. An axial flux rotor for use in a motor and for cooperation with a stator, said rotor comprising:
a body defining an axis of rotation thereof, said body having first and second opposed faces, said body defining a plurality of pockets formed in first face of said body, said body comprising a plurality of overlaid layers, wherein said body includes an outer periphery defined by an outside radius OR, a central opening defined by an inner radius IR and a number N of rotor poles defining an axis of rotation thereof; and
a plurality of spaced apart magnets, each of said plurality of magnets matingly fitted to one of said plurality of pockets, wherein at least one of said magnets has a minimum length D min defined by

D
min

=

π
*

(

OR
+
IR

)

*
BrS

2
*
N
*
BrA

,

wherein BrS is Remnant Flux Density of a Surface Mounted Magnet, wherein OR is the outside radius of the body, wherein IR is the inner radius of the body, wherein N is the number of rotor poles, and wherein BrA is Remnant Flux Density of an Axially Imbedded Magnet.

8. The axial flux rotor of claim 7 , wherein said body comprises a plurality of connectable segments.

9. An axial flux motor comprising:
a housing;
a stator fixedly secured to said housing;
a rotor rotatably secured to said housing, said rotor including, a body defining an axis of rotation thereof, said body having first and second opposed faces, said body defining a plurality of pockets formed in first face of said body, said body comprising a plurality of overlaid layers; and
a plurality of spaced apart magnets, each of said plurality of magnets matingly fitted to one of said plurality of pockets, wherein said at least one of said plurality of pockets comprises a minimum depth D min defined by

D
min

=

(

π
*

(

R
⁢

⁢
1

+

R
⁢

⁢
2

)

)

2
*
n

,

wherein R 1 is a radius of an outer edge of the rotor, R 2 is a radius of an inner edge of the rotor, and n is a number of rotor poles.

10. The axial flux motor of claim 9 , wherein said rotor is substantially cylindrical and comprises a plurality of rotor poles, the outer edge having the radius R 1 , and the inner edge defining a central opening having the radius R 2 .

11. The axial flux motor of claim 9 , wherein said motor comprises a number of said stator teeth that is different than a number of said plurality of magnets.

12. The axial flux motor of claim 9 , wherein said stator comprises:
a plurality of stator modules oriented in an axial direction, each of said stator modules comprising a pair of teeth connected by a yoke section; and
a plurality of windings, each of said windings wound around one of said stator modules.

13. The axial flux motor of claim 12 , further comprising a plurality of bobbins, wherein said bobbins are coupled to said teeth, and said windings are wound around said bobbins.

14. The axial flux motor of claim 13 , further comprising a plurality of tooth tips, wherein said tooth tips are coupled to said bobbins.

15. The axial flux motor of claim 14 , wherein said plurality of stator modules and said plurality of tooth tips are fabricated from a plurality of stacked laminations.

16. The axial flux motor of claim 14 , wherein said stator modules are generally C-shaped and said plurality of tooth tips are generally T-shaped.

17. The axial flux moto

Assignees

• Regal Beloit America Inc

Inventors

• Brahmavar Subhash Marutirao

Classifications

• H02K1/2795 Primary

  the rotor consisting of two or more circumferentially positioned magnets · CPC title

• H02K3/524

  for U-shaped, E-shaped or similarly shaped cores · CPC title

• H02K15/028

  Fastening stator or rotor bodies to casings, supports, shafts or hubs · CPC title

• H02K1/141

  consisting of C-shaped cores · CPC title

• H02K21/24 Primary

  with magnets axially facing the armatures, e.g. hub-type cycle dynamos · CPC title