Rotating electrical machine

Patent metadata

Field	Value
Publication number	US-2016352164-A1
Application number	US-201615231821-A
Country	US
Kind code	A1
Filing date	Aug 9, 2016
Priority date	Aug 11, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

Provided is a rotating electrical machine that has superior rotor strength and can be manufactured at low cost, wherein torque generated by a rotor can be increased. Two holes are formed in a circumferential direction in each pole in a rotor. The two holes communicate with an outer periphery of the rotor, and an outer peripheral edge portion on an outer side in a radial direction of the rotor of the two holes is connected via a center bridge between the two holes to a core portion on an inner side in the radial direction of the rotor in each pole. The center bridge is demagnetized, or the permeability thereof is reduced. Consequently, leakage flux passing through the center bridge can be reduced, even when the width of the center bridge is increased.

First claim

What is claimed is:

1 . A rotating electrical machine comprising a rotor in which an even number of holes neighboring in a circumferential direction and sandwiching a center bridge are formed in each pole, wherein
the even number of holes sandwich the center bridge in each pole of the rotor and communicate with an outer periphery of the rotor on a side opposite to a side of the center bridge, a region on a central side in a radial direction of the rotor of an inner peripheral wall of the even number of holes inclines farther in a direction away from the central side in the radial direction of the rotor as the region is approached from a center of neighboring poles toward the center bridge, and the center bridge is demagnetized, or a permeability of the center bridge is reduced further than a permeability of a portion of the rotor other than the center bridge.

2 . The rotating electrical machine according to claim 1 , wherein
the center bridge is demagnetized, or the permeability thereof is reduced, by a transformation or causing of distortion to be carried out by utilizing heat treatment or work hardening.

3 . The rotating electrical machine according to claim 2 , wherein
the center bridge is located on an outer side, in a radial direction of the rotor, of an inscribed circle of the even number of holes.

4 . The rotating electrical machine according to claim 1 , wherein
the rotor has a q axis projection that protrudes in a direction away from a central axis of rotation of the rotor between neighboring poles.

5 . The rotating electrical machine according to claim 2 , wherein
the rotor has a q axis projection that protrudes in a direction away from a central axis of rotation of the rotor between neighboring poles.

6 . The rotating electrical machine according to claim 3 , wherein
the rotor has a q axis projection that protrudes in a direction away from a central axis of rotation of the rotor between neighboring poles.

7 . The rotating electrical machine according to claim 1 , wherein
at least one of the even number of holes holds a permanent magnet, and the rotating electrical machine is a permanent magnet embedded type rotating electrical machine.

8 . The rotating electrical machine according to claim 7 , wherein
one portion or a whole of an outer peripheral surface of an outer peripheral edge portion has a radius of curvature smaller than a distance from a central axis of rotation of the rotor to an outermost peripheral portion of the rotor.

9 . The rotating electrical machine according to claim 7 , wherein
a region of an inner wall of the at least one of the even number of holes on an outer side in the radial direction of the rotor has a positioning projection that restricts movement of the permanent magnet.

10 . The rotating electrical machine according to claim 7 , wherein
fixing of the permanent magnet is aided by an adhesive.

11 . The rotating electrical machine according to claim 1 , wherein
the rotating electrical machine is a synchronous reluctance rotating electrical machine.

12 . The rotating electrical machine according to claim 11 , wherein
one portion or a whole of an outer peripheral surface of an outer peripheral edge portion has a radius of curvature greater than a distance from a central axis of rotation of the rotor to an outermost peripheral portion of the rotor.

13 . The rotating electrical machine according to claim 2 , wherein
at least one of the even number of holes holds a permanent magnet, and the rotating electrical machine is a permanent magnet embedded type rotating electrical machine.

14 . The rotating electrical machine according to claim 3 , wherein
at least one of the even number of holes holds a permanent magnet, and the rotating electrical machine is a permanent magnet embedded type rotating electrical machine.

15 . The rotating electrical machine according to claim 4 , wherein
at least one of the even number of holes holds a permanent magnet, and the rotating electrical machine is a permanent magnet embedded type rotating electrical machine.

16 . The rotating electrical machine according to claim 2 , wherein
the rotating electrical machine is a synchronous reluctance rotating electrical machine.

17 . The rotating electrical machine according to claim 3 , wherein
the rotating electrical machine is a synchronous reluctance rotating electrical machine.

18 . The rotating electrical machine according to claim 4 , wherein
the rotating electrical machine is a synchronous reluctance rotating electrical machine.

19 . A rotor, comprising:
a core portion; an outer peripheral edge portion; and a center bridge connecting the core portion to the outer peripheral edge portion; wherein holes are formed on either side of the center bridge and have lower edges that incline outwardly in a rotor radial direction and toward the center bridge, and the center bridge has a lower permeability than another portion of the rotor.

20 . The rotor of claim 19 , further comprising magnets in the holes.

Assignees

• Fuji Electric Co Ltd

Inventors

• Mochida Toshiharu
• Imamori Satoshi

Classifications

• H02K19/10

  for multi-phase current · CPC title

• H02K15/03

  having permanent magnets · CPC title

• H02K21/14

  with magnets rotating within the armatures · CPC title

• H02K1/276 Primary

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

• H02K1/2766

  having a flux concentration effect · CPC title