JP2008017671A - Permanent magnet type rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet type rotary electric machine capable of suppressing the repellency of a magnet junction part divided to reduce eddy currents. <P>SOLUTION: The permanent magnet type rotary electric machine has such structure that a permanent magnet 10 is embedded in a rotor core 30. The permanent magnet 10 is composed of magnets 10a and 10b divided for reduced eddy currents. Since the magnets 10a and 10b are jointed across a magnetic plate 40 which is coated for insulation, the magnetic plate 40 is magnetically attracted from both magnets 10a and 10b, to suppress the repellency of the junction part, resulting in the effect of preventing the peeling of the magnets 10a and 10b. Further, since the magnetic plate 40 is coated for insulation, the eddy currents between the magnets 10a and 10b are reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a permanent magnet type rotating electrical machine including a permanent magnet. In particular, the present invention relates to a structure that can reduce the eddy current of a permanent magnet.

  Conventionally, as described in Cited Document 1, in a motor (Interior Permanent Magnet: IPM) in which a permanent magnet is embedded in a rotor core made of a high permeability material such as iron, a magnet is used as a countermeasure against eddy current. It is divided in the direction, and an insulating layer is sandwiched between them and embedded in the rotor core.

For example, as shown in FIG. 3, the insulating paper 20 is sandwiched and bonded between the divided magnets 10a and 10b.
Further, as shown in the cited document 2, in the two-pole permanent magnet rotating electrical machine, the permanent magnet embedded in the rotor core is divided in the circumferential direction in order to reduce eddy current loss.
JP 2000-324736 JP2002-231201 JP2002-136006

  However, in the embedded magnet motor, as shown in FIG. 3, the N poles and S poles of the magnets 10a and 10b face each other, so that the repulsive force between the magnets 10a and 10b sandwiches the insulating paper 20 between them. Therefore, there is a problem that the magnets 10a and 10b are peeled off before being inserted into the rotor core of the motor.

In addition, in a surface permanent magnet (SPM) motor that attaches a permanent magnet to the surface of the rotor core, if the magnet is divided as a measure against eddy current, the magnet's repulsive force will cause the magnet to jump out. Yes, the magnet may not stick well.
In addition, as shown in Patent Document 3, an embedded magnet type motor using a plurality of permanent magnets shorter than the core stacking length (axial length) of a rotor core or stator core formed by laminating a plurality of base steel plates In Japanese Patent Application Laid-Open No. 2004-260260, there is known one in which an attractive force is applied between magnets by inserting a magnet spacer between a plurality of magnets embedded in a rotor core.

  The present invention has been made in view of the above-described prior art, and an object of the present invention is to provide a permanent magnet type rotating electrical machine that can suppress repulsion of a magnet joint divided to reduce eddy current.

  The permanent magnet type rotating electrical machine according to claim 1 of the present invention for solving the above-mentioned problems is a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is embedded in a rotor core, wherein the permanent magnet is divided to reduce eddy currents. And being bonded with a magnetic material plate having an insulating coating interposed therebetween.

  The permanent magnet type rotating electrical machine according to claim 2 of the present invention that solves the above problems is a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is attached to the surface of a rotor core. The permanent magnet reduces eddy currents. Therefore, the magnetic plates are divided and bonded with an insulating coating interposed therebetween.

  A permanent magnet type rotating electrical machine according to a first aspect of the present invention is a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is embedded in a rotor core, and a magnetic body sandwiched between joints of magnets divided for eddy current countermeasures. Since the plate is magnetically attracted to both the magnets, there is an effect of suppressing the repulsion of the joint and preventing the magnet from peeling off. Further, since the magnetic plate is coated with insulation, eddy currents between the magnets are reduced.

  A permanent magnet type rotating electrical machine according to claim 2 of the present invention is a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is attached to the surface of a rotor core, and is sandwiched between joints of magnets that are divided for eddy current countermeasures. Since the magnetic material plate is magnetically attracted to both the magnets, there is an effect of suppressing repulsion of the joint portion and preventing the magnet from jumping out. Further, since the magnetic plate is coated with insulation, eddy currents between the magnets are reduced.

  Hereinafter, the modes described as the first and second embodiments are the best modes for carrying out the present invention.

A permanent magnet type rotating electrical machine according to a first embodiment of the present invention is shown in FIG. This embodiment relates to an embedded magnet type motor (IPM).
That is, as shown in FIG. 1A, magnets 10 are embedded in the rotor core 30 at four locations along the axial direction, and these magnets 10 are divided into two in the axial direction for eddy current countermeasures. Magnets 10a and 10b, and a magnetic plate 40 is sandwiched and bonded between the magnets 10a and 10b.

The magnetic plate 30 can suppress repulsion of the magnets 10a and 10b on both sides because the magnetic attractive force acts on the magnets 10a and 10b on both sides.
The cross section of the magnetic material plate 40 is rectangular as with the magnets 10a and 10b, and the thickness is about 1 to 3 mm.
Since the surface of the magnetic plate 40 is coated with an insulating material (not shown), the eddy current is blocked between the magnets 10a and 10b.
The manufacturing method will be described. As shown in FIG. 1 (b), after magnets 10a and 10b are bonded with an insulating-coated magnetic body plate 40 sandwiched therebetween, a rotor as shown in FIG. 1 (a) is obtained. It is completed by inserting it into the iron core 30.

As described above, in the embedded magnet type motor according to the present embodiment, the magnetic material plate 40 having an insulation coating of about 1 to 3 mm in thickness is provided between the magnets 10a and 10b divided for the countermeasure against eddy current. The magnets 10 a and 10 b and the magnetic plate 40 are inserted into the rotor core 30 after being sandwiched and bonded.
Therefore, the insulating coating formed on the magnetic plate 40 can reduce the eddy current between the magnets 10a and 10b, and the magnetic plate 30 can be magnetically attracted to the magnets 10a and 10b on both sides. Therefore, the repulsion of the magnets 10a and 10b on both sides can be suppressed, and the magnets 10a and 10b are effectively prevented from peeling off.

  In the above-described embodiment, the magnets 10a and 10b are divided into two parts in the axial direction for the purpose of eddy current countermeasures. The same effect can be achieved by sandwiching the magnetic plate.

A permanent magnet type rotating electrical machine according to a second embodiment of the present invention is shown in FIG. The present embodiment relates to a surface magnet pasted motor (SPM).
That is, as shown in FIG. 2, an annular magnetic plate 60 that protrudes along the circumferential direction is formed at the central portion in the axial direction of the rotor core 70 as a countermeasure against eddy currents. A large number of magnets 50a and 50b are attached to the surface of the rotor core 70 with a gap therebetween.

The magnetic plate 60 can suppress repulsion of the magnets 50a and 50b on both sides because the magnetic attractive force acts on the magnets 50a and 50b. The thickness of the magnetic plate 60 is about 1 to 3 mm.
Since the surface of the magnetic plate 60 is coated with an insulating material (not shown), the eddy current is interrupted between the magnets 50a and 50b.
As described above, the surface magnet affixed motor according to this embodiment is a magnetic plate with an insulation coating of about 1 to 3 mm in thickness between magnets 50a and 50b divided for eddy current countermeasures. 60 is affixed to the surface of the rotor core 70 with the 60 interposed therebetween.

  Therefore, the insulating coating formed on the magnetic plate 60 can reduce the eddy current between the magnets 50a and 50b, and the magnetic plate 60 is magnetically attracted to the magnets 50a and 50b on both sides. Therefore, the repulsion of the magnets 50a and 50b on both sides can be suppressed, and there is an effect of preventing the magnets 50a and 50b from jumping out.

  The present invention relates to a permanent magnet type rotating electrical machine including a permanent magnet, and can be applied to any of an embedded magnet type motor and a surface magnet pasting type motor.

FIG. 1A is a perspective view of an embedded magnet type motor (IPM) according to a first embodiment of the present invention, and FIG. 1B is a diagram showing magnetic coating with insulation coating between magnets divided for eddy current countermeasures. It is explanatory drawing which shows a mode that it adhere | attaches on both sides of a body board. It is a perspective view of the surface magnet pasting type motor (SPM) concerning the 2nd example of the present invention. It is explanatory drawing which shows a mode that an insulating paper is pinched | interposed and bonded between the magnets divided | segmented for the eddy current countermeasure concerning a prior art.

Explanation of symbols

10a, 10b, 50a, 50b Magnet 20 Insulating paper 30, 70 Rotor core 40, 60 Magnetic plate (insulating coating)

Claims (2)

  In a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is embedded in a rotor core, the permanent magnet is divided in order to reduce eddy current, and is joined with a magnetic material plate with an insulating coating interposed therebetween. Permanent magnet type rotating electric machine. In a permanent magnet type rotating electrical machine having a structure in which a permanent magnet is attached to the surface of a rotor core, the permanent magnet is divided in order to reduce eddy currents and bonded with an insulating coating magnetic plate interposed therebetween. Permanent magnet type rotating electrical machine.

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