Rotor core with plurality of permanent magnets and magnet holes with bridges between magnets/magnet holes

Patent metadata

Field	Value
Publication number	US-12519353-B2
Application number	US-202118034809-A
Country	US
Kind code	B2
Filing date	Dec 21, 2021
Priority date	Jan 8, 2021
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

A laminated core of this rotor core includes one side magnet hole provided on one side in a circumferential direction with respect to a d-axis, an other side magnet hole provided on the other side, an intermediate magnet hole, a first outer bridge portion, a second outer bridge portion, a first inner bridge portion, and a second inner bridge portion.

First claim

The invention claimed is:

1 . A rotor core, comprising:
an annular laminated core formed by stacking a plurality of electrical steel sheets; and a plurality of permanent magnets forming a plurality of magnetic poles arranged circumferentially, wherein the laminated core includes, in each of the plurality of magnetic poles, a one side magnet hole that is provided on one side in a circumferential direction with respect to a d-axis and into which the permanent magnet is inserted, an other side magnet hole that is provided on the other side in the circumferential direction with respect to the d-axis and into which the permanent magnet is inserted, an intermediate magnet hole that is formed by a single hole and that is provided between the one side magnet hole and the other side magnet hole and into which at least two permanent magnets of the plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward, a first outer bridge portion provided between a radially outer end of the one side magnet hole and an outer edge of the laminated core, a second outer bridge portion provided between a radially outer end of the other side magnet hole and the outer edge, a first inner bridge portion provided between the one side magnet hole and the intermediate magnet hole and connecting a radially inner portion of the laminated core and a radially outer portion of the laminated core, and a second inner bridge portion provided between the other side magnet hole and the intermediate magnet hole and connecting the radially inner portion and the radially outer portion.

2 . The rotor core according to claim 1 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

3 . The rotor core according to claim 1 , wherein an angle formed by a direction in which the one side magnet hole extends and the d-axis, and an angle formed by a direction in which the other side magnet hole extends and the d-axis is smaller than ½ of a bending angle of the intermediate magnet hole.

4 . The rotor core according to claim 1 , wherein each of the first inner bridge portion and the second inner bridge portion is tilted toward the d-axis in such a manner that radial outer sides of the first inner bridge portion and the second inner bridge portion are located closer to the d-axis as viewed in an axial direction of the laminated core.

5 . The rotor core according to claim 4 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

6 . The rotor core according to claim 1 , wherein
each of the one side magnet hole and the other side magnet hole is provided so as to extend in a radial direction, and the laminated core is configured in such a manner that the permanent magnet inserted into the one side magnet hole, the permanent magnet inserted into the other side magnet hole, and the plurality of permanent magnets inserted into the intermediate magnet hole are arranged in a W-shape.

7 . The rotor core according to claim 6 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

8 . The rotor core according to claim 6 , wherein each of the first inner bridge portion and the second inner bridge portion is tilted toward the d-axis in such a manner that radial outer sides of the first inner bridge portion and the second inner bridge portion are located closer to the d-axis as viewed in an axial direction of the laminated core.

9 . The rotor core according to claim 8 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

10 . The rotor core according to claim 6 , wherein
the intermediate magnet hole is formed by the single hole that is bent into a convex shape pointing radially outward and into which the plurality of permanent magnets is inserted, and a magnetic gap is formed between the permanent magnets inserted into the intermediate magnet hole.

11 . The rotor core according to claim 10 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

12 . The rotor core according to claim 10 , wherein each of the first inner bridge portion and the second inner bridge portion is tilted toward the d-axis in such a manner that radial outer sides of the first inner bridge portion and the second inner bridge portion are located closer to the d-axis as viewed in an axial direction of the laminated core.

13 . The rotor core according to claim 12 , wherein the laminated core includes an outer magnet hole that is provided radially outward from the intermediate magnet hole and into which a plurality of the permanent magnets is inserted so as to be arranged in a convex shape pointing radially outward.

Assignees

• Aisin Corp
• Toyota Motor Co Ltd

Inventors

• Saito Naoto
• IIJIMA Ami
• Tsuda Teppei
• Okochi Toshinori

Classifications

• H02K29/03

  with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems · CPC title

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title

• Y02T10/64

  Electric machine technologies in electromobility · CPC title

• H02K1/276 Primary

  Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

• H02K1/2766 Primary

  having a flux concentration effect · CPC title