Direct drive rotor with metal coupler

Patent metadata

Field	Value
Publication number	US-9391487-B2
Application number	US-201414270083-A
Country	US
Kind code	B2
Filing date	May 5, 2014
Priority date	Aug 17, 2010
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

A rotor for an outer rotor-type motor is provided. The rotor includes a metallic coupler and a polymeric frame molded over at least part of the metallic coupler.

First claim

The invention claimed is:

1. A rotor for an outer rotor-type electric motor, said rotor being rotatable about an axis, the rotor comprising:
a metallic coupler including—
an inner axial surface configured to interface with a shaft to be driven by the rotor when the motor is energized,
an outer axial surface that corresponds to a multiplicity of outer teeth, and
a first generally radial surface; and

a polymeric frame including a hub,
said hub engaging the first generally radial surface,
said outer teeth engaging the hub such that torque is transmitted from the coupler to the frame,
each of said outer teeth having a generally arcuate tooth width, W tooth , and a generally radial tooth depth, D tooth ,
each tooth width W tooth being about 62% of the corresponding tooth depth D tooth .

2. The rotor of claim 1 ,
each tooth width W tooth being about 1.25 mm,
each tooth depth D tooth being about 2 mm.

3. The rotor of claim 1 ,
each of said outer teeth defining a peak,
said outer axial surface defining a valley between each adjacent pair of said outer teeth,
adjacent ones of said peaks being spaced apart a generally arcuate distance S peaks ,
adjacent ones of said valleys being spaced apart a generally arcuate distance S valley ,
S valleys being about 90.4% of S peaks .

4. The rotor of claim 1 , wherein the outer teeth are selected from the group consisting of knurls, splines, keys, diamond knurls, or combinations thereof.

5. The rotor of claim 4 , wherein the outer teeth are knurls.

6. The rotor of claim 1 , wherein the number of outer teeth is at least 20 and no more than about 40.

7. The rotor of claim 6 , wherein the number of outer teeth is 30.

8. The rotor of claim 1 ,
said coupler having a nominal outer diameter, OD coupler , and a height, H coupler ,
D tooth being about 5% of OD coupler , and from about 5% to about 10% of H coupler .

9. The rotor of claim 8 ,
said rotor having an outer diameter, OD rotor , and a height, H rotor ,
OD coupler being less than about 20% of OD rotor ,
H coupler being no more than about 45% of H rotor .

10. A rotor for an outer rotor-type electric motor, said rotor being rotatable about an axis, the rotor comprising:
a metallic coupler including—
an inner axial surface configured to interface with a shaft to be driven by the rotor when the motor is energized,
an outer axial surface that corresponds to a multiplicity of outer teeth, and
a first generally radial surface; and

a polymeric frame including a hub,
said hub engaging the first generally radial surface,
said outer teeth engaging the hub such that torque is transmitted from the coupler to the frame,
said coupler having a nominal outer diameter, OD coupler ,
each of said outer teeth having a radial tooth depth, D tooth , that is about 5% of OD coupler .

11. The rotor of claim 10 ,
each tooth depth D tooth being about 2 mm,
OD coupler being about 41.5 mm.

12. The rotor of claim 10 , wherein the rotor has an outer diameter, OD rotor , wherein OD coupler is less than about 20% of OD rotor .

13. The rotor of claim 12 , wherein OD coupler is less than about 15% of OD rotor .

14. The rotor of claim 10 , wherein the rotor has an outer diameter, OD rotor , and wherein the hub has an outer diameter, OD hub , that is less than about 30% of OD rotor .

15. The rotor of claim 14 , wherein OD hub is less than about 20% of OD rotor .

16. A rotor for an outer rotor-type electric motor, said rotor being rotatable about an axis, the rotor comprising:
a metallic coupler including—
an inner axial surface configured to interface with a shaft to be driven by the rotor when the motor is energized,
an outer axial surface that corresponds to a multiplicity of outer teeth, and
a first generally radial surface; and

a polymeric frame including a hub,
said hub engaging the first generally radial surface,
said outer teeth engaging the hub such that torque is transmitted from the coupler to the frame,
said coupler having a height, H coupler ,
each of said outer teeth having a generally radial tooth depth, D tooth , that is from about 5% to about 10% of H coupler .

17. The rotor of claim 16 ,
each of said tooth depths D tooth being about 2 mm,
H coupler being between about 20 mm and about 40 mm.

18. The rotor of claim 17 ,
H coupler being about 28 mm.

19. The rotor of claim 16 , wherein the rotor has a height, H rotor , wherein H coupler is no more than about 45% of H rotor .

20. The rotor of claim 19 , wherein H coupler is no more than about 40% of H rotor .

Assignees

• Nidec Motor Corp

Inventors

• Bailey Daniel E
• Hilton Daniel E
• Johnson Philip S
• Levine Gregory M

Classifications

• H02K7/003 Primary

  Couplings; Details of shafts (means for mounting rotors on shafts H02K1/28) · CPC title

• H02K1/30

  using intermediate parts, e.g. spiders · CPC title

• H02K1/2786

  Outer rotors · CPC title

• D06F37/304 Primary

  Arrangements or adaptations of electric motors · CPC title

• H02K15/12

  Impregnating, moulding insulation, heating or drying of windings, stators, rotors or machines · CPC title