IP Library Granted Patent US 7,420,312
Granted Patent B2
US 7,420,312 · App. 11/342,667 · Granted Sep 2, 2008

Rotating electrical machine

Assignee: Mitsubishi Denki Kabushiki Kaisha
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Quick Facts
Patent No.
US 7,420,312
App. No.
11/342,667
Granted
Sep 2, 2008
Kind
B2
Abstract

Provided is a rotating electrical machine including an armature core on which an armature winding is wound; a rotor core which is supported by a rotation axis at a predetermined air gap in an inner diameter side of the armature core, and includes claw-shaped magnetic pole portions in which adjacent magnetic poles have different poles and a cylindrical portion having a field winding; and a permanent magnet which is provided in a magnetic circuit of the rotor core and supplies magnetic flux to the armature core with the field winding, wherein a magnetic short-circuiting mechanism for demagnetizing the magnetic flux of the permanent magnet by deforming a portion of the magnetic short-circuiting mechanism by a centrifugal force and short-circuiting between the magnetic pole portions of the rotor core is provided in the rotor core.

Claims (14)

1. A rotating electrical machine comprising:

an armature core on which an armature winding is wound;

a rotor core which is supported by a rotation axis at a predetermined air gap in an inner diameter side of the armature core, and includes claw-shaped magnetic pole portions, in which adjacent magnetic poles have different polarities, and a cylindrical portion having a field winding; and

a permanent magnet which is provided in a magnetic circuit of the rotor core and which, together with the field winding, supplies magnetic flux to the armature core,

wherein the rotor core is provided with a magnetic short-circuiting mechanism for reducing the magnetic flux, supplied by the permanent magnet to the armature core, by creating a short-circuit, between the magnetic pole portions of the rotor core, by deforming a portion of the magnetic short-circuiting mechanism by a centrifugal force.

2. The rotating electrical machine according to claim 1 , wherein, the magnetic short-circuiting mechanism is made of a magnetic body, a fixing portion attached to one magnetic pole portion of the rotor core and an elastic deformation portion which extends from the fixing portion to the facing surface of the adjacent other magnetic pole portion through a connecting portion and short-circuits between the both magnetic pole portions in a high-speed rotation area configure a magnetic short-circuiting body unit, and a plurality of magnetic short-circuiting body units is formed in a ring shape in succession.

3. The rotating electrical machine according to claim 1 , wherein, the magnetic short-circuiting mechanism is made of a magnetic body, a fixing portion attached to one magnetic pole portion of the rotor core and an elastic deformation portion which extends from the fixing portion to the facing surfaces of the adjacent other magnetic pole portions through connecting portions in the both sides and short-circuits between the both magnetic pole portions by at least a predetermined rotation speed configure a magnetic short-circuiting body unit, and a plurality of magnetic short-circuiting bodies is sequentially formed in succession.

4. The rotating electrical machine according to claim 1 , wherein, in the magnetic short-circuiting mechanism, a connecting portion and elastic deformation portions which extend to the facing surfaces of adjacent magnetic pole portions in the both sides of the connecting portions and short-circuit between the both magnetic pole portions by at least a predetermined rotation speed configure a magnetic short-circuiting body unit, a plurality of magnetic short-circuiting body units is connected to a ring-shaped non-magnetic ring made of a non-magnetic material, and the non-magnetic ring is engaged to the magnetic pole portions.

5. The rotating electrical machine according to claim 1 , wherein, in the magnetic short-circuiting mechanism, a fixing portion attached to one magnetic pole portion of the rotor core and an elastic deformation portion which extends from the fixing portion to the facing surface of one of the adjacent magnetic pole portions and short-circuits between the both magnetic pole portions by at least a predetermined rotation speed configure a magnetic short-circuiting body unit, and a plurality of magnetic short-circuiting body units is sequentially formed in succession.

6. The rotating electrical machine according to claim 2 , wherein the elastic deformation portion faces the inner circumferential surface of the magnetic pole portion at a predetermined interval, comes into contact with the inner circumferential surface of the opposite magnetic pole portion by acceleration having at least a predetermined rotation number of the rotor core, and goes away from the inner circumferential surface of the opposite magnetic pole portion by deceleration having a rotation number equal to or smaller than the predetermined rotation number of the rotor core.

7. The rotating electrical machine according to claim 3 , wherein the elastic deformation portion faces the inner circumferential surface of the magnetic pole portion at a predetermined interval, comes into contact with the inner circumferential surface of the opposite magnetic pole portion by acceleration having at least a predetermined rotation number of the rotor core, and goes away from the inner circumferential surface of the opposite magnetic pole portion by deceleration having a rotation number equal to or smaller than the predetermined rotation number of the rotor core.

8. The rotating electrical machine according to claim 4 , wherein the elastic deformation portion faces the inner circumferential surface of the magnetic pole portion at a predetermined interval, comes into contact with the inner circumferential surface of the opposite magnetic pole portion by acceleration having at least a predetermined rotation number of the rotor core, and goes away from the inner circumferential surface of the opposite magnetic pole portion by deceleration having a rotation number equal to or smaller than the predetermined rotation number of the rotor core.

9. The rotating electrical machine according to claim 5 , wherein the elastic deformation portion faces the inner circumferential surface of the magnetic pole portion at a predetermined interval, comes into contact with the inner circumferential surface of the opposite magnetic pole portion by acceleration having at least a predetermined rotation number of the rotor core, and goes away from the inner circumferential surface of the opposite magnetic pole portion by deceleration having a rotation number equal to or smaller than the predetermined rotation number of the rotor core.

10. The rotating electrical machine according to claim 1 , wherein the magnetic short-circuiting mechanism is formed in a plate shape material containing both a magnetic material and an elastic material.

Assignments (2)
COMPANY SPLIT Recorded Sep 4, 2024
From: MITSUBISHI ELECTRIC CORPORATION
To: MITSUBISHI ELECTRIC MOBILITY CORPORATION
Reel/Frame 068834/0585 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 4, 2006
From: KITAMURA, YUTAKA; ASAO, YOSHIHITO; AKITA, HIROYUKI
To: MITSUBISHI DENKI KABUSHIKI KAISHA
Reel/Frame 017861/0214 →
Priority Claims (1)
JP P2005-029161 · Feb 4, 2005 · national
Continuity (1)
Related Publication 20060186754A1 · Aug 24, 2006