IP Library Granted Patent US 7,906,885
Granted Patent B2
US 7,906,885 · App. 11/916,996 · Granted Mar 15, 2011

Brushless electric machine

Assignees: Union Plastic (Hangzhou) Machinery Co., Ltd.; Hsiaoting Lu; Weiting Lu
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Quick Facts
Patent No.
US 7,906,885
App. No.
11/916,996
Granted
Mar 15, 2011
Kind
B2
Abstract

A brushless electric machine includes a rotor and a stator. Each of the twin poles of the stator electromagnetic members corresponds to one of the two magnetic poles of the rotor magnetic assembles. Two radial component air-gaps are arranged between the stator and the rotor to separate the stator and the rotor. Axial component air-gaps axially corresponding are arranged between the stator poles and the corresponding rotor poles to separate the stator poles and the rotor poles. The stator wheel-shaped ring is partly surrounded by the rotor wheel-shaped ring.

Claims (24)

1. A brushless electric machine comprising:

a rotor including a plurality of magnetic elements containing permanent magnet arranged along a circumferential direction about a revolving shaft to form a rotor wheel-shaped ring, with each said magnetic element having respectively two magnetic poles; and

a stator including a plurality of magnetically isolated electromagnetic members coaxially arranged around the revolving shaft to form a stator wheel-shaped ring, each said electromagnetic member having twin poles,

wherein each pole of the twin poles of the electromagnetic members of the stator corresponds to one magnetic pole of the magnetic poles of the magnetic elements of the rotor respectively,

wherein two radial component air-gaps are arranged between the stator and the rotor to separate the stator from the rotor, wherein axially aligned axial component air-gaps are arranged between the stator pole and the corresponding rotor pole to separate the stator pole from the corresponding rotor pole, and

wherein stator wheel-shaped ring is partly surrounded by the rotor wheel-shaped ring.

2. The brushless electric machine of claim 1 , wherein the axially aligned axial component air-gaps are arranged between the stator pole and the corresponding rotor pole to separate the stator pole from the corresponding rotor pole, and wherein the number of the axially aligned axial component air-gaps between the stator pole and the rotor pole is zero.

3. The brushless electric machine of claim 2 , wherein the pole face of the stator pole and the pole face of the corresponding rotor pole at the axial component air-gaps do not coexist.

4. The brushless electric machine of claim 1 , wherein the amount of the axially aligned axial component air-gaps defined between the stator pole and the corresponding rotor pole is even.

5. The brushless electric machine of claim 4 , wherein the pole face amount of the stator pole and the corresponding rotor pole at the axial component air-gaps are same.

6. The brushless electric machine of claim 1 , wherein said twin poles of each said electromagnetic member of the stator is connected by a ferromagnetic core segment, with a winding formed on the core segment, with the winding, when energized with current, creating opposite magnetic polarities on respective pole faces of said twin poles of each said electromagnetic member of the stator, with said pole faces of each said pole having the same magnetic polarity, and with the magnetic polarities of said pole faces of said twin poles being reversed when the current passes the winding in a reverse direction.

7. The brushless electric machine of claim 6 , wherein the stator has a non-ferromagnetic support structure, and wherein each said electromagnetic member of the stator is fixed independently by said non-ferromagnetic support structure to the stator such that said electromagnetic members of the stator have no ferromagnetic contact therebetween.

8. The brushless electric machine of claim 6 , wherein the pole face of each of the two magnetic poles of each said magnetic element of the rotor exhibits a single magnetic polarity opposite to that of the other pole of said two magnetic poles.

9. The brushless electric machine of claim 8 , wherein each said magnetic element includes a coupling seat made of ferromagnetic material, with the plurality of permanent magnets mounted to an inner surface of each said magnetic element to form the two magnetic poles of the magnetic element, and with a surface of each said permanent magnet facing the air-gap exhibiting a single magnetic polarity opposite to that of a rear surface of the permanent magnet mounted to the inner surface of the coupling seat of said magnetic element.

10. The brushless electric machine of claim 6 , wherein the plurality of permanent magnets of the rotor arranged along the circumferential direction about the revolving shaft successively alternate in magnetic polarities (N/S) along the circumferential direction about the revolving shaft.

11. The brushless electric machine of claim 6 , wherein one of said twin poles of each said electromagnetic member of the stator which said pole face facing component air gaps amount are three, and wherein one of said three component air-gaps is radial component air-gap, and the others are axial component air-gaps.

12. The brushless electric machine of claim 11 , wherein each pole of said twin poles of each said electromagnetic member of the stator having three component air-gaps has a substantially U-shaped cross section and includes three pole faces, with a bottom pole face of the three pole faces facing the radial component air-gap, with the two radial component air-gaps between the rotor and the stator being located on opposite sides of the stator in the radial direction, and with the other two pole faces facing the respective axial component air-gaps.

13. The brushless electric machine of claim 9 , wherein one of said two magnetic poles of said magnetic elements of the rotor which said pole face facing component air-gaps amount are three, and wherein one of said three component air-gaps is radial component air-gap, and the others are axial component air-gaps.

14. The brushless electric machine of claim 13 , wherein each said magnetic element includes a C-shaped coupling seat made of ferromagnetic material, with the plurality of permanent magnets mounted to an inner surface of each said magnetic element to form the two magnetic poles of the magnetic element, and each said magnetic pole of said magnetic element having separately three pole faces having identical magnetic polarity, with a first of the three pole faces parallel to the revolving shaft facing one of the radial component air-gaps, and with the other two pole faces facing the respective axial component air-gaps.

15. The brushless electric machine of claim 14 , wherein the permanent magnet of each magnetic poles of said magnetic element has a substantially U-shaped cross section to form three pole faces of the magnetic pole, with a bottom pole face of each said U-shaped cross section with said three pole face parallel to the revolving shaft.

16. The brushless electric machine of claim 9 , wherein the permanent magnets on the two magnetic poles of each said magnetic element are substantially separated by radial gaps from each other.

17. The brushless electric machine of claim 10 , wherein adjacent said permanent magnets arranged along the circumferential direction about the revolving shaft are spaced by one of the gaps from each other.

18. The brushless electric machine of claim 17 , wherein adjacent said permanent magnets along the circumferential direction about the revolving shaft are spaced by one of the gaps and have no ferromagnetic contact from each other.

19. The brushless electric machine of claim 9 , wherein said coupling seat of each said magnetic element of said rotor is made of non-ferromagnetic material.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 9, 2007
From: LU, WEITING
To: UNION PLASTIC (HANGZHOU) MACHINERY CO., LTD.; LU, HSIAOTING; LU, WEITING
Reel/Frame 020217/0527 →
Priority Claims (1)
CN 2005 1 0035656 · Jun 29, 2005 · national
Continuity (1)
Related Publication 20090102305A1 · Apr 23, 2009