JPH1118324A - Rotating machine and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the influence of leakage flux upon characteristics of a rotating machine while strength of an ion core is ensured, by applying modification for reducing permeability to a part of at least one iron core of a rotor and a stator in which leakage flux is generated. SOLUTION: Recessed slits 12 which are formed in the same direction as a rotating shaft, and a plurality of big and small polar parts 14a, 14b which are formed between the slits 12, are arranged on the outer surface of a rotor iron core 10 of an inner magnet rotor of a rotating machine. Slots 16 for inserting permanent magnets are arranged on base parts of every other polar parts 14a. Bridge parts 20 of side parts of short sides of the slots 16 are irradiated with a laser beam and treated by heating. Permeability of the slots 16 is made lower than that of other parts. As a result, the influence of leakage flux upon characteristics of the rotating machine can be improved without reducing the thicknesses of the bridge parts 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating machine and a method of manufacturing the same, and more particularly, to a technique for improving the influence of a leakage magnetic flux generated on a rotor or a stator core on a rotating machine.

[0002]

2. Description of the Related Art Conventionally, in a rotating machine such as an electric motor or a generator, a leakage magnetic flux, which is a magnetic flux interlinking only with its own iron core, is generated in a core of a rotor or a stator. The leakage inductance due to the magnetic flux hinders the rectifying action in a DC machine or an AC commutator machine, causes a voltage drop as a reactance in an AC machine, and adversely affects the characteristics of the rotating machine. For this reason,
Conventionally, a treatment such as reducing the thickness of an iron core is applied to a portion where a leakage magnetic flux is generated, and a device is devised so as to improve the influence of the magnetic leakage on a rotating machine even if a little.

FIG. 5 is a view of a rotor core of an inner magnet type rotor viewed from an axial direction. A substantially cylindrical rotor core 10 shown in FIG. 1 is made of laminated electromagnetic steel sheets, and has slits 12 formed in the outer surface thereof in the same direction as the rotation axis. Magnetic pole portions 14a, 1
4b is formed. And every other magnetic pole part 14
At the base of a, a slot 1 for inserting a permanent magnet having a rectangular cross section
6 have been established.

When a permanent magnet 18 is inserted into the slot 16 so that the direction of the magnetic poles coincides with the radial direction, a part of the magnetic pole portion which is in contact with the permanent magnet in a direction perpendicular to the magnetic pole direction, that is, Magnetic flux leakage occurs in the bridge portion 20. FIG. 6 is an enlarged view of the magnetic pole portion 14a of the inner magnet type rotor viewed from the axial direction. As shown in the figure, a magnetic flux interlinking only with the rotor core 10, that is, a leakage magnetic flux 22 is generated in the bridge portion 20 on the side of the permanent magnet 18. In order to improve the influence of the leakage magnetic flux 22 on the characteristics of the rotating machine, the thickness of the bridge portion 20 is reduced as much as possible.

FIG. 7 is an axial front view of the stator core. The stator core 23 shown in the figure includes an inner piece 24 located inward and a hollow cylindrical outer piece 26 into which the inner piece 24 is inserted. The inner piece 24 has 12 magnetic poles 28 in total.
At the edge of the pole piece 30 of the adjacent magnetic pole 28,
The pole pieces 28 are integrally connected to each other so as to face a rotor (not shown) located inside. The inner piece 24 is inserted into the outer piece 26, and a slot 32 is formed in a portion surrounded by the adjacent magnetic pole 28 and the inner wall of the outer piece 26.

According to the stator core 23, each magnetic pole 2 of the inner piece 24 is not inserted into the outer piece 26.
8, the inner piece 24 can then be inserted into the outer piece 26. As a result, each magnetic pole 2
8 can be easily wound.

FIG. 8 shows each magnetic pole 2 of the inner piece 24.
8 is an enlarged view of the connecting portion 34 of FIG. 8 viewed from the axial direction. As shown in the figure, in this stator, a leakage magnetic flux 36 that links only to the stator core 23 is generated around each slot 32. The stator is formed by reducing the thickness of the connecting portion 34 of the magnetic pole as much as possible in order to improve the influence of the leakage magnetic flux 36 on the characteristics of the rotating machine.

[0008]

However, in these rotors and stators, if the thickness of the portion where the leakage magnetic fluxes 22 and 36 are generated is reduced, the strength required for the rotating machine cannot be secured. That is, in the inner-magnet type rotor shown in FIG. 5, if the thickness of the bridge portion 20 is reduced, it becomes difficult to hold the permanent magnet 18 inserted into the slot 16. In particular, in the rotor, the permanent magnet 1 is driven when the rotating machine is driven.
Since 6 receives centrifugal force, it is necessary to give sufficient strength to the bridge portion 20 to hold it. FIG.
In the stator shown in (1), if the thickness of the connecting portion 34 of the magnetic pole 28 is reduced, the strength required to maintain the integral shape of the inner piece 24 cannot be secured.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotating machine capable of improving the effect of leakage magnetic flux on the characteristics of the rotating machine while securing the strength of an iron core. It is to provide a manufacturing method.

[0010]

In order to solve the above-mentioned problems, a rotating machine according to the present invention reduces a magnetic permeability in a portion of at least one of a rotor and a stator where a leakage magnetic flux is generated. It is characterized by being subjected to alteration processing.

According to the present invention, the portion of the iron core of the rotating machine in which the leakage magnetic flux is generated is subjected to a pressure treatment for generating strain, dislocation and stress, and a transformation treatment for reducing magnetic permeability such as heating. . This makes it possible to improve the effect of the leakage magnetic flux on the characteristics of the rotating machine while securing the strength of the iron core.

The rotating machine according to the present invention is a rotating machine including a rotor having a permanent magnet provided inside a core, wherein the permanent magnet is arranged in a direction perpendicular to a magnetic pole direction of the permanent magnet. At least a portion of the iron core that is in contact with each other has been subjected to an alteration treatment for reducing magnetic permeability.

[0013] As described above, in the portion of the iron core that is in contact with the permanent magnet in a direction perpendicular to the magnetic pole direction of the permanent magnet, the leakage magnetic flux that does not contribute to the torque of the rotating shaft that is linked only to this iron core. Occurs. Then, in the present invention, at least a part of this portion is subjected to the alteration treatment. Therefore, it is possible to improve the effect of the leakage magnetic flux on the characteristics of the rotating machine while securing the strength of the iron core.

Further, the rotating machine according to the present invention includes a stator core in which a plurality of magnetic poles arranged in the same direction as the axis of the rotating shaft are connected to each other at the rotor side edge outside the rotor. A rotating machine, characterized in that an alteration process for reducing magnetic permeability is applied to a connection portion thereof.

As described above, in the stator core, if the magnetic poles are connected on the rotor side, a leakage magnetic flux interlinking only with the stator core occurs across those magnetic poles. According to the present invention, since the alteration processing is performed on the connecting portion, it is possible to improve the effect of the leakage magnetic flux on the characteristics of the rotating machine while securing the strength of the iron core.

As the above-mentioned alteration treatment for decreasing the magnetic permeability, welding such as laser welding can be employed. According to this alteration treatment, impurities in the iron core can be miniaturized, and they can be dispersed and precipitated. As a result, it is possible to hinder the movement of the domain wall and reduce the magnetic permeability of the portion where the leakage magnetic flux is generated. When the iron core is made of a laminated electromagnetic steel sheet, all the leaves can be welded and integrated.

Further, as the alteration process for lowering the magnetic permeability, a process for generating at least one of distortion and dislocation in the material, such as pressing with a roller, may be employed. According to the alteration process, it is possible to hinder the movement of the domain wall in the iron core and reduce the magnetic permeability of the portion where the leakage magnetic flux is generated. Furthermore, when a part of the iron core is plastically deformed to cause strain or dislocation, the material strength of the part can be improved.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1A is a partial perspective view showing a rotor core of an inner-magnet type rotor of the rotating machine according to Embodiment 1, and FIG. 1B is surrounded by a dashed line in FIG. It is a figure which expands and shows a part. The rotor core 10 shown in the figure is the same as the rotor core 10 already shown in FIGS. 5 and 6, and each leaf 38 made of a material such as an electromagnetic steel sheet is laminated and formed in a substantially cylindrical shape. The rotor core 10 is provided with a shaft hole 40 for attaching a rotating shaft at the center, and a slit 12 in the same direction as the rotating shaft is formed on the outer surface. A plurality of large and small magnetic pole portions 14a and 14b extending in the axial direction are formed between the slits 12. Further, a slot 16 for inserting a permanent magnet having a rectangular cross section is formed at the base of every other magnetic pole portion 14a. Permanent magnets are attached to these slots 16 so that the magnetic poles are oriented in the radial direction.

The short side of the slot 16, that is, the bridge portion 20, is laser-welded.
That is, when manufacturing the rotor, the rotor core 10
In a state where the leaves 38 are stacked, they are fixed by a predetermined jig (not shown), and thereafter, the inner wall 42 of the slit 12 located on the side of the bridge portion 20 is irradiated with laser light.
The aim is moved up and down in the axial direction and moved linearly over all leaves. In this way, the laser beam-irradiated portion of each leaf 38 can be melted to integrate all the leaves. In this rotor, since the bridge portion 20 is heated by irradiating the bridge portion 20 with a laser beam, the bridge portion 20 can be altered so as to reduce the magnetic permeability. This is because impurities in the iron core are miniaturized and dispersed and precipitated, so that movement of the domain wall becomes difficult.

As described above, in the present inner-magnet type rotor, the bridge portion 20 where the leakage magnetic flux is generated on the side of the permanent magnet is formed.
Is irradiated with a laser beam to perform a heat treatment, so that the magnetic permeability of this portion has been successfully reduced as compared with other portions. For this reason, the influence of the leakage magnetic flux on the characteristics of the rotating machine can be improved without reducing the thickness of the bridge portion 20. Further, in the present internal magnetic rotor, since the leaves 38 of the rotor core 10 are welded by laser welding, the leaves 38 can be integrated without using caulking or through bolts.

The above-described rotor can be variously modified. For example, in the above description, the laser welding is performed on the bridge portion 20 of the rotor core 10, but the magnetic permeability can be similarly reduced by simply performing a process of heating the bridge portion 20.

In the above-mentioned rotor, a structure for integrating the laminated rotor cores 10 such as caulking is not provided, but a structure such as caulking or a through bolt may be additionally provided.

Further, in the rotor according to the above description, the bridge portion 20 of the rotor core 10 is subjected to laser welding.
In addition to or instead of this, the bridge section 20 may be subjected to a process of causing distortion or dislocation.

FIG. 2 is a view for explaining this processing, and is an enlarged view of the rotor core 10 of the inner magnet type rotor with the bridge portion 20 as the center. First, as shown in FIG. 3A, two relatively small rollers 44 are moved in the axial direction while pressing in the direction of the arrow in FIG. You may. By doing so, strain, dislocation, or stress can be generated in the bridge portion 20, and as a result, movement of the domain wall is inhibited, and magnetic permeability can be reduced.

According to the rotor according to this modification, the influence of the leakage magnetic flux on the characteristics of the rotating machine can be improved without reducing the thickness of the bridge portion 20. Further, since the rollers are set inside the slots 16, the end faces of the respective leaves 38 of the iron core can be leveled to reduce the dimensional tolerance. In addition, it is also possible to obtain the effect of integrating the leaves of the rotor core 10 by plastically deforming the ends of the respective leaves 38 and engaging them with each other. In addition, if plastic deformation is given to the iron core by roller hanging, the material strength of the rotor iron core 10 can be locally improved.

FIGS. 7B and 7C show still another modification of the inner magnet type rotor. That is, as shown in FIG. 3B, a wide cylindrical roller 46 may be applied to the inner wall of the slot 16 of the inner magnet type rotor facing the bridge portion 20 while pressing in the direction of the arrow in the figure. Alternatively, FIG.
As shown in (1), a roller 48 may be inserted from the outer surface of the bridge portion 20, that is, from the slit 12, and the roller may be applied to this portion.

Even in this case, strain, dislocation, or stress can be generated in the bridge portion 20, and the movement of the domain wall is inhibited, so that the magnetic permeability can be reduced. As a result, it is possible to improve the influence of the leakage magnetic flux on the characteristics of the rotating machine without reducing the thickness of the bridge portion 20. Further, if plastic deformation is given to the iron core by the roller hooking, the material strength of the rotor iron core 10 can be improved.

Embodiment 2 FIG. 3 is a partial perspective view showing an inner piece constituting a stator of the rotating machine according to the second embodiment. The inner piece 24 shown in the figure is the same as the inner piece 24 of the stator core 23 already shown in FIGS. 7 and 8, and a plurality of magnetic poles 28 are integrally formed at the edge of the pole piece 30 of the adjacent magnetic poles. The magnetic pole pieces 30 are opposed to a rotor (not shown) located inside.

In the marking impedance 24 according to the present embodiment, the laser welding 50 is applied to the connecting portions 34 of the magnetic poles 28 over all the leaves of the laminated core. That is, when manufacturing the inner piece 24, the laminated electromagnetic steel sheets are fixed by a predetermined jig, and then the connecting portions 34 of the magnetic poles 28 on the side walls of the inner piece 24.
Is irradiated with laser light up and down. In this case, since the laser beam irradiated portion of each leaf is melted, all the leaves can be integrated. Further, when the laser beam is irradiated as described above, the connecting portion of the magnetic poles is heated, so that this portion can be transformed so as to lower the magnetic permeability.

As described above, since the inner piece 24 is subjected to the heat treatment by irradiating the laser beam to the portion where the leakage magnetic flux is generated (the connection portion 34), the inner piece 24 does not leak without reducing the thickness of this portion. The effect of the magnetic flux on the characteristics of the rotating machine can be improved. Further, since each leaf of the laminated electromagnetic steel sheet is welded by laser welding 50, each leaf of the iron core can be easily integrated without using caulking or through bolts.

The above-described rotor is used in the first embodiment.
Various modifications can be made in the same manner as described above. For example, in the above description, the laser welding 50 is performed on the connecting portion 34 of the magnetic pole 28, but the magnetic permeability of the portion can be similarly reduced by simply performing a process of heating the connecting portion 34.

In the stator inner piece 24 according to the above description, the connecting portion 34 of the magnetic pole 28 is
However, in addition to or instead of this, a process of causing distortion or dislocation in the connecting portion 34 may be performed. Specifically, a roller 52 may be applied to the connecting portion 34 of the magnetic pole 28 from the inside as shown in FIG. 7A, or a roller 54 may be applied from the outside as shown in FIG. By doing so, strain, dislocation, or stress can be generated in the connection portion 34, and as a result, the movement of the domain wall is inhibited, and the magnetic permeability can be reduced. Thus, according to the inner piece 24 according to this modification, it is possible to improve the influence of the leakage magnetic flux on the characteristics of the rotating machine without reducing the thickness of the connecting portion 34 of the magnetic pole 28. In addition, the end of each leaf of the iron core can be plastically deformed to be engaged with each other, so that the effect of integrating the laminated iron core can be obtained. Further, if plastic deformation is given to the iron core by roller hanging, the material strength of the iron core can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a rotor core of a rotating machine according to Embodiment 1 of the present invention.

FIG. 2 is a diagram illustrating a modified example of the rotor core according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a part of a stator core of a rotating machine according to Embodiment 2 of the present invention.

FIG. 4 is a diagram illustrating a modification of the stator core according to the second embodiment of the present invention.

FIG. 5 is a view showing a conventional rotor.

FIG. 6 is an enlarged view showing a magnetic pole portion of a conventional rotor.

FIG. 7 is a view showing a conventional stator.

FIG. 8 is an enlarged view showing a connection portion of magnetic poles in a conventional stator.

[Explanation of symbols]

10 rotor core, 12 slits, 14a, 14b,
28 magnetic poles, 16, 32 slots, 18 permanent magnets,
Reference Signs List 20 bridge part, 23 stator core, 24 inner piece, 26 outer piece, 34 connecting part, 44, 4
6, 48, 52, 54 rollers, 50 laser welding.

Claims (6)

[Claims] 1. A rotating machine characterized in that at least one of a core of a rotor and a stator has a portion where leakage magnetic flux is generated, which is subjected to an alteration process for reducing magnetic permeability. 2. A rotating machine including a rotor having a permanent magnet installed inside an iron core, wherein at least a part of the iron core which is in contact with the permanent magnet in a direction perpendicular to the magnetic pole direction of the permanent magnet, A rotating machine that has been subjected to an alteration process to reduce magnetic permeability. 3. A rotating machine having a stator core in which a plurality of magnetic poles disposed outside the rotor in the same direction as the axis of the rotating shaft are connected to each other at an edge on the rotor side. A rotating machine that has been subjected to an alteration process to reduce magnetic permeability. 4. The rotating machine according to claim 1, wherein the altering process for decreasing the magnetic permeability includes:
A rotating machine characterized by welding. 5. The rotating machine according to claim 1, wherein the alteration process for reducing the magnetic permeability is performed by causing at least one of strain and dislocation in the material. Rotating machine. 6. A method for manufacturing a rotating machine, wherein a portion of at least one of a rotor and a stator, in which a leakage magnetic flux is generated, is subjected to an alteration process for reducing magnetic permeability.