Rotary electric machine

Patent metadata

Field	Value
Publication number	US-2024396416-A1
Application number	US-202218694991-A
Country	US
Kind code	A1
Filing date	Jun 17, 2022
Priority date	Sep 30, 2021
Publication date	Nov 28, 2024
Grant date	—

Abstract

A rotary electric machine includes: a rotor having a shaft extending in an axial direction and rotor magnets arranged along a circumferential direction; a stator having a coil and surrounding the rotor; a housing supporting the stator; a pair of magnetic bearings on opposite sides in the axial direction of the rotor magnet; and a position adjusting member held by the housing. The stator holds the rotor rotatably in the axial direction by a field current flowing through the coil. The magnetic bearing includes a cylindrical inner magnet fixed to the rotor and a cylindrical outer magnet fixed to the housing and surrounding the inner magnet, and holds the rotor rotatably in the radial direction. The rotor has a stepped surface facing the axial direction. The position adjusting member has an opposing surface facing the stepped surface, and is movable in the axial direction with respect to the housing.

First claim

1 . A rotary electric machine comprising:
a rotor having a shaft extending in an axial direction with a central axis as a center and a plurality of rotor magnets arranged along a circumferential direction, the rotor rotating about the central axis; a stator including a coil and surrounding the rotor from a radially outer side; a housing that supports the stator; a pair of magnetic bearings respectively located on one side and another side in the axial direction of the rotor magnet; and a position adjusting member held by the housing, wherein the stator rotatably holds the rotor in the axial direction by a field current caused to flow through the coil, the pair of magnetic bearings each include an inner magnet having a cylindrical shape and fixed to the rotor and an outer magnet having a cylindrical shape and fixed to the housing and surrounding the inner magnet, and rotatably hold the rotor in a radial direction, the rotor has a stepped surface facing the axial direction, and the position adjusting member has an opposing surface facing the stepped surface, and is movable in the axial direction with respect to the housing.

2 . The rotary electric machine according to claim 1 , further comprising
a pair of the position adjusting members, wherein the pair of position adjusting members are respectively located on the one side and the other side in the axial direction of the rotor magnet, and have the opposing surfaces facing opposite sides in the axial direction.

3 . The rotary electric machine according to claim 1 , wherein
the housing includes a holding portion that holds the position adjusting member, the holding portion includes a nut portion extending in the axial direction with the central axis as a center, and a male screw to be inserted into the nut portion is provided on an outer peripheral surface of the position adjusting member.

4 . The rotary electric machine according to claim 3 , wherein the holding portion covers at least a part of an end surface facing the axial direction of the outer magnet.

5 . The rotary electric machine according to claim 3 , wherein
the holding portion has a gap facing surface axially facing the inner magnet via a gap, and the position adjusting member protrudes from the gap facing surface in the axial direction.

6 . The rotary electric machine according to claim 3 , wherein
the housing includes: a magnet holding portion that holds the outer magnet; and a cover that covers the position adjusting member, and the holding portion is sandwiched between the magnet holding portion and the cover in the axial direction.

7 . The rotary electric machine according to claim 1 , wherein the position adjusting member is provided with a central hole penetrating in the axial direction with the central axis as a center, and the shaft passes through the central hole.

Assignees

• Nidec Corp

Inventors

• Sasaki Ryoma
• Hirose Kentaro
• Maeda Shigeru

Classifications

• H02K2213/09

  Machines characterised by the presence of elements which are subject to variation, e.g. adjustable bearings, reconfigurable windings, variable pitch ventilators · CPC title

• H02K7/09 Primary

  with magnetic bearings · CPC title

• F16C32/04

  using magnetic or electric supporting means · CPC title

• H02K21/024 Primary

  Radial air gap machines · CPC title