Spoke permanent magnet rotor

Patent metadata

Field	Value
Publication number	US-10069357-B2
Application number	US-201314648817-A
Country	US
Kind code	B2
Filing date	Nov 8, 2013
Priority date	Nov 30, 2012
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

The present invention relates to a spoke-type permanent magnet rotor (1) used in brushless direct current electric motors (16), forming the rotating part inside a stator (17) that forms the stationary part thereof and having an air gap (18) between the inner surface of the stator (17) and itself, comprising a cylindrical core (2) produced from ferro-magnetic laminations or ferromagnetic powder metal, a shaft (3) fixed to the core (2) and forming the rotational axis of the rotor (1), a hub (5) disposed at the center of the core (2) and having a shaft hole (4) that bears the shaft (3), more than one pole segment (6) disposed all around the hub (5), more than one magnet slot (7) arranged between the pole segments (6), more than one magnet (8) tangentially magnetized, placed in the magnet slots (7) and extending outwards in the radial direction, and two end rings (9) produced from non-magnetic materials such as aluminum and plastic and fixed on the front and rear planar surfaces of the core (2) by the injection molding method.

First claim

The invention claimed is:

1. A rotor comprising:
a cylindrical ferromagnetic core;
a shaft forming a rotational axis thereof;
a hub disposed at the center of the cylindrical ferromagnetic core, wherein the hub has a shaft hole that bears the shaft;
a plurality of pole segments disposed around the hub;
a plurality of magnet slots, wherein a magnet slot of the plurality of magnet slots is arranged between two consecutive pole segments of the plurality of pole segments, and wherein each magnet slot is configured to receive a magnet extending outwards in a radial direction;
a first end ring and a second end ring produced from non-magnetic material and fixed on the front and rear planar surfaces of the cylindrical ferromagnetic core, respectively; and
a plurality of inner columns disposed in the shaft hole and around the shaft, wherein the plurality of inner columns are formed on a surface of the first end ring facing the hub, wherein the plurality of inner columns partially contact the shaft, wherein a first recess is provided between a first set of consecutive inner columns of the plurality of inner columns, wherein a second recess is provided between a second set of consecutive inner columns of the plurality of inner columns, and wherein each of the first recess and the second recess is in line with a different magnet slot of the plurality of magnet slots.

2. The rotor as in claim 1 , further comprising:
a plurality of bridges, wherein a bridge of the plurality of bridges extends in the radial direction between the plurality of pole segments and the hub to connect the plurality of pole segments and the hub, wherein the bridge has a thickness narrower than an edge from which a pole segment is connected to the hub, and wherein the plurality of bridges serve as flux barriers between the opposite poles of the adjacent magnets on both sides of the pole segment.

3. The rotor as in claim 2 , further comprising:
a plurality of support extensions that support the plurality of magnets by extending from around the hub into each magnet slot in the radial direction.

4. The rotor as in claim 3 , wherein a support extension of the plurality of support extensions is shaped as a triangle with vertexes contacting the magnet, narrowing from the hub towards the magnet, and wherein the plurality of support extensions serve as flux barriers between the opposite poles of each magnet.

5. The rotor as in claim 2 , further comprising:
a plurality of openings arranged between the plurality of bridges and a plurality of support extensions and surrounding the hub.

6. The rotor as in claim 5 , further comprising:
a plurality of bars, wherein a bar of the plurality of bars is produced by injecting non-magnetic material into an opening of the plurality of openings, wherein the bar extends along the cylindrical ferromagnetic core in the axial direction between the first end ring and the second end ring, and wherein the plurality of bars form a cage around the hub.

7. The rotor as in claim 2 , further comprising:
a plurality of recesses arranged in the shaft hole and opening from around the shaft into the hub.

8. The rotor as in claim 7 , wherein a plurality of inner columns are produced by injecting non-magnetic material into the plurality of recesses, wherein the plurality of inner columns extend along the cylindrical ferromagnetic core in the axial direction between the first end ring and the second end ring, and wherein the plurality of inner columns form a cage around the shaft.

9. The rotor as in claim 1 , further comprising:
a plurality of support extensions, wherein a support extension of the plurality of support extensions supports the magnet by extending from around the hub toward the magnet slot in the radial direction.

10. The rotor as in claim 9 , wherein the support extension is shaped as a triangle with vertexes contacting the magnet, narrowing from the hub towards the magnet, and wherein the plurality of support extensions serve as flux barriers between the opposite poles of each magnet of the plurality of magnets.

11. The rotor as in claim 9 , further comprising:
a plurality of bridges extending in the radial direction between the plurality of pole segments and the hub to connect the plurality of pole segments and the hub; and
a plurality of openings arranged between the plurality of bridges and the plurality of support extensions, wherein the plurality of openings surround the hub.

12. The rotor as in claim 11 , further comprising:
a plurality of bars, wherein a bar of the plurality of bars is produced by injecting non-magnetic material into an opening of the plurality of openings, wherein the bar extends along the cylindrical ferromagnetic core in the axial direction between the first end ring and the second end ring, and wherein the plurality of bars form a cage around the hub.

13. The rotor as in claim 1 , further comprising:
a plurality of recesses arranged in the shaft hole and opening from around the shaft into the hub.

14. The rotor as in claim 13 , wherein an inner column of the plurality of inner columns is produced by injecting non-magnetic material into a recess of the plurality of recesses, wherein the inner column extends along the cylindrical ferromagnetic core in the axial direction between the first end ring and the second end ring, and wherein the plurality of inner columns form a cage around the shaft.

15. The rotor as in claim 1 , wherein a surface of the first end ring is on a first plane, wherein the first end ring includes a plurality of magnet slots, wherein a magnet slot of the plurality of magnet slots has a surface on a second plane, the second plane below the first plane, wherein the magnet slot has a first end and a second end opposite from the first end, wherein the first end abuts a portion of the first end ring that has a surface on a third plane above the first plane and the second plane.

Assignees

• Arcelik As

Inventors

• Ekin Cihad
• Sonmez Emin Gultekin
• Imat Yakup
• Orhan Huseyin

Classifications

• H02K1/2773 Primary

  consisting of tangentially magnetized radial magnets · CPC title

• H02K1/30

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

• H02K1/28

  Means for mounting or fastening rotating magnetic parts on to, or to, the rotor structures · CPC title