Rotating electrical machine

Patent metadata

Field	Value
Publication number	US-11309777-B2
Application number	US-202117192263-A
Country	US
Kind code	B2
Filing date	Mar 4, 2021
Priority date	Mar 9, 2020
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

A rotating electrical machine capable of obtaining a higher torque while limiting the amount of permanent magnets used. A magnetic pole of a rotor includes an auxiliary magnet embedded in a rotor core and at least one main magnet arranged on an outer circumferential side than the auxiliary magnet of the rotor. In each magnetic pole, the distance from an end of the main magnet, the end facing the auxiliary magnet, to the auxiliary magnet facing the main magnet is shorter than the length of the main magnet in the radial direction. In a cross-section orthogonal to the rotation axis of the rotating electrical machine, the main magnets of each magnetic pole are arranged so as to be asymmetrical about a virtual line passing the rotation axis and axisymmetrically dividing the auxiliary magnet.

First claim

What is claimed is:

1. A rotating electrical machine comprising:
a rotor with permanent magnets embedded in a rotor core made of a soft magnetic material; and
a stator positioned on an outer circumference of the rotor,
wherein:
the permanent magnets include a main magnet arranged so as to be magnetized in a radial direction or a circumferential direction of the rotor, and an auxiliary magnet arranged so as to be magnetized in the radial direction of the rotor,
the auxiliary magnet includes a plurality of auxiliary magnets, the plurality of auxiliary magnets being embedded in the rotor core so as to surround a rotation axis of the rotor in a cross-section orthogonal to the rotation axis,
the main magnet includes a plurality of main magnets, the plurality of main magnets being embedded in the rotor core so as to extend from the auxiliary magnets in an outer circumferential direction of the rotor,
a plurality of magnetic poles of the rotor is formed around the rotation axis, the magnetic poles each having the auxiliary magnet and at least one of the main magnets arranged on an outer circumferential side than the auxiliary magnet of the rotor,
in each magnetic pole, a distance from an end of the main magnet, the end facing the auxiliary magnet, to the auxiliary magnet facing the main magnet is shorter than a length of the main magnet in the radial direction, and
in the cross-section orthogonal to the rotation axis, the main magnet of each magnetic pole is arranged such that the permanent magnets are arranged asymmetrically about a virtual line passing the rotation axis and axisymmetrically dividing the auxiliary magnet of each magnetic pole.

2. The rotating electrical machine according to claim 1 , wherein the main magnet is arranged so as to be magnetized in the circumferential direction of the rotor.

3. The rotating electrical machine according to claim 1 , wherein each of the magnetic poles has two or more of the main magnets, and the soft magnetic material is disposed between the main magnets.

Assignees

• Toyota Motor Co Ltd

Inventors

• Kanada Keiu
• Ichigozaki Daisuke
• Haga Kazuaki
• Hiraoka Motoki
• Maruyama Daichi
• Toshida Hisamitsu
• Nakamura Kyoko
• Yamashita Akira

Classifications

• H02K21/029 Primary

  Vectorial combination of the fluxes generated by a plurality of field sections or of the voltages induced in a plurality of armature sections · CPC title

• H02K1/2773 Primary

  consisting of tangentially magnetized radial magnets · CPC title

• H02K1/274

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

• H02K1/276

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

• H02K1/272

  the magnetisation axis of the magnets being perpendicular to the rotor axis · CPC title