JPH104661A - Ac generator and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the workability of the assembling work of an AC generator provided with a plurality of magnets by providing a plurality of independent magnets, arranged between cores and a magnet-retaining member, which couple the magnets with each other and is mounted on the core, together with the magnets. SOLUTION: A nonmagnetic ring 31 has magnet-retaining sections, respectively composed of side face sections housing permanent magnets 41 and outer peripheral sections, and the bottom sections of the ring 31 constitute connecting sections which connect the magnet-retaining sections to each other. The ring 31 functions as a retaining member which retains the magnets 41 in a coupling state, before the ring 31 is assembled in pole cores 11 and 21. Consequently, the magnets 41 are coupled with each other by the ring 31, and the magnets 41 and nonmagnetic body 31 can be handled as an assembly. Therefore, the magnets 41 can be handled collectively and can be assembled easily between the cores 11 and 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alternator equipped with a plurality of magnets and a method of manufacturing the alternator, and is particularly suitable for an alternator for a vehicle.

[0002]

2. Description of the Related Art In recent years, low noise and high output have been demanded as social needs for vehicle alternators. Here, as a technique for improving the output of the vehicle alternator, for example, a technology disclosed in Japanese Patent Application Laid-Open No. 61-85045, “Vehicle Alternator” is known.

[0003]

In the rotor of the automotive alternator disclosed in the above publication, an effective magnetic flux contributing to power generation is generated by a permanent magnet as an auxiliary magnet provided between the claw portions of a pole core serving as claw-shaped magnetic poles. In addition, the output can be improved, the physique can be reduced in size, and the like. However, in such a conventional technique, when arranging a permanent magnet between a plurality of claw-shaped magnetic poles, an annular permanent magnet is arranged, or an individual permanent magnet is arranged, and an individual permanent magnet is arranged. Has the problem that the assembly work becomes difficult,
In the case of an annular permanent magnet, not only is it difficult to form a permanent magnet having a complicated shape, but also a large permanent magnet is required.

[0004] The present invention has been made to solve the problems of the prior art. An object of the present invention is to improve the workability of assembling an alternator equipped with a plurality of magnets. An object of the present invention is to provide an AC generator having a structure excellent in assembly workability.

[0005] It is an object of the present invention to provide a method of manufacturing an alternator having excellent assembling workability.

[0006]

According to the present invention, there is provided an AC generator having a field coil for exciting a core of a rotor. A plurality of magnets and a magnet holding member attached to the core together with the magnets, the technical means being an AC generator.

By adopting such means and connecting a plurality of independent magnets with a magnet holding member, the plurality of independent magnets can be handled as an assembly, and the workability when mounting the magnets on the core is improved. Can be greatly improved. In addition, since a magnet holding member different from a magnet is used, effects such as reduction in magnet material and weight can be obtained.

It is preferable that the magnet holding member includes a plurality of holding portions provided for each magnet and holding the magnet, and a connecting portion connecting the plurality of holding portions. You may. By employing such a magnet holding member, it is possible to further improve workability, such as ensuring the positioning of the magnet.

Further, technical means may be adopted in which the magnet holding member is made of a non-magnetic metal. Further, technical means that the magnet holding member is made of resin may be employed. By employing a non-magnetic material such as a non-magnetic metal or resin, it is possible to provide a magnet holding member that does not affect the magnetic characteristics of the rotor core or the magnet.

[0010] Further, technical means may be employed in which the magnet is insert-molded in the resin. According to such a configuration, the plurality of magnets can be reliably held. Further, technical means that the magnet is a permanent magnet may be adopted. In such a configuration, the amount of permanent magnet material, in which the magnet material is generally more expensive as the magnet is stronger, can be reduced, so that in addition to the cost reduction accompanying the improvement in workability, further cost reduction is achieved by reducing the expensive permanent magnet material. Is achieved.

Further, the core may be a pole core having a plurality of claw portions, and technical means may be employed in which the magnet holding member is disposed in contact with a root portion inside the claw portion. . According to this configuration, even when the rotor rotates at a high speed, a centrifugal load via the magnet holding member is applied to the base of the claw having relatively high strength in the centrifugal direction. Can be suppressed and deformation of the claw portion due to centrifugal force can be suppressed.

In addition, a technical means is adopted in which the core is a pole core having a plurality of claw portions, and the magnet holding member is disposed along the root side from the claw tip side inside the claw portion. May be. According to this configuration, since the magnet holding member is attached along the claw portion that becomes thicker from the claw tip end side toward the claw base side, the magnet holding member is attached to the claw portion while absorbing mutual dimensional errors. Can be installed.

[0013] The magnet holding member may employ a technical means in which all of the plurality of magnets are connected. According to such a configuration, all magnets mounted on the core are connected, so that all magnets can be collectively handled as an assembly, and excellent workability is realized.
In order to achieve the above object, the present invention provides a method of manufacturing an AC generator having a field coil for exciting a rotor core, wherein a plurality of independent magnets are connected by a magnet holding member. After forming the three-dimensional structure, the assembly is mounted on the core, and technical means of a method of manufacturing an AC generator is adopted.

As described above, by attaching a plurality of magnets to the core after assembling them by connecting a plurality of magnets with the magnet holding member, a plurality of magnets can be attached to the core collectively, resulting in excellent workability. As a result, waste of magnet material can be reduced and weight can be reduced. It is to be noted that a technical means may be adopted in which the magnet is mounted on a magnet holding member in which a plurality of magnet holding portions are connected by a connecting portion to form the assembly.

By adopting such a method, it is possible to further improve the workability such as ensuring the positioning of the magnet. Further, a technical means may be employed in which a plurality of the magnets are insert-molded and attached to a magnet holding member to form the assembly. By adopting such a method, it is possible to further improve the workability such as ensuring the positioning of the magnet and securing the magnet.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on some examples. First, a first embodiment will be described. FIG. 1 is a longitudinal sectional view showing a configuration of a rotor of an automotive alternator according to the present invention, and FIG. 2 is a view showing a state where a pair of pole cores, a non-magnetic ring and a permanent magnet are assembled. It is a perspective view. FIG. 3 is a partial perspective view showing a nonmagnetic ring in which permanent magnets are disposed on the inner surface,
FIG. 4 is a partial vertical sectional view taken along the line IV-IV of FIG. The rotor 10 of the vehicle alternator mainly includes pole cores 11 and 21 as cores and a non-magnetic ring 3.
1, a permanent magnet 41 as an auxiliary magnet, a field coil 45 as electromagnetic exciting means, a shaft 46,
It is composed of fans 48 and 49.

The pole cores 11 and 21 are formed with a plurality of claw portions 12 and 22 which are claw-shaped magnetic poles protruding in the axial direction on the outer peripheral side. The pole cores 11 and 21 are combined with the pawl portions 12 and 22 facing each other so as to be alternately positioned in the circumferential direction. And are integrally assembled.

As shown in FIG. 4, the nonmagnetic ring 31 has a side surface 32 in contact with the side surfaces 13 and 23 of the pawl portions 12 and 22 of the pole cores 11 and 21, and a bottom portion 33 thereof. , 22 are formed so as to be in contact with the inner side surfaces 14, 24, and to fill the space between the opposing claws 12, 22 and have the same outer diameter surface as the outer diameter surfaces of the claws 12, 22. .

On the inner surface 35 of the outer peripheral portion 34 of the non-magnetic ring 31, a permanent magnet 41 is provided with a field coil 45.
And a gap. The permanent magnet 41 is magnetized so as to prevent a leakage magnetic flux between the magnetic poles of the claw portions 12 and 22 of the pole cores 11 and 21. As described above, the permanent magnet 41 as a magnet is disposed between the claw portions 12 and 22, which are leakage magnetic flux paths of the pole cores 11 and 21 as cores excited by the field coil 45. The permanent magnet 41 is held by a plate-shaped nonmagnetic ring 31 as a magnet holding member, and is easily and reliably held between the claw portions of the pole core.

Here, the non-magnetic ring 31 constitutes a magnet holding portion by the side surface portion 32 accommodating the permanent magnet 41 and the outer peripheral portion 34, and the bottom portion 33 connects between the magnet holding portions. It constitutes a connecting part. In addition, the bottom part 33 as a connecting part is in contact with the inner side surfaces 14, 24 of the claw parts 12, 22, and is particularly arranged along the root side from the tip side thereof, and the base parts of the claw parts 12, 22. It is in contact with the inner surface of the part. For this reason, the nonmagnetic ring 31 is
2, 22 can be mounted from the tip side, and in the mounted state, it is supported in the centrifugal direction at the base of the claw which has relatively high strength in the centrifugal direction, so even when the rotor rotates at high speed The movement of the nonmagnetic ring 31 due to the centrifugal force and the deformation of the claw are suppressed.

Next, the operation will be described. Field coil 4
5 is supplied to a stator (not shown) disposed close to the outer peripheral surfaces of the pole cores 11 and 21 through the pole cores 11 and 21. 22 also flows as leakage magnetic flux.

Here, the claw portions 1 of the pole cores 11 and 21
Since the permanent magnets 41 are disposed between the second and the second 22, the leakage magnetic flux can be reduced, and the effective magnetic flux can be increased by utilizing a part of the leakage magnetic flux as the effective magnetic flux. As a result, as shown in FIG. 5, the output current with respect to the rotation speed can be increased as compared with the case where the permanent magnet 41 is not disposed between the claw portions 12 and 22 of the pole cores 11 and 21.

As described above, the nonmagnetic ring 3
1 is the side surface 1 of the pawl portions 12 and 22 of the pole cores 11 and 21
Fill the gaps between 3 and 23 and the outer peripheral portion 3
4 is formed so as to be the same as the outer diameter of the claw portions 12 and 22. Therefore, the rotor 10 of this vehicle alternator is
Are claw portions 12, 2 of the pole cores 11, 21 even if they rotate at a high speed.
No wind noise occurs because there is no centrifugal fan effect due to 2.

Further, a gap is provided over the entire circumference between the non-magnetic ring 31 and the field coil 45, and the ventilation inside the pole cores 11 and 21 is not impaired. Does not adversely affect cooling. Further, by using a plastic magnet for the permanent magnet 41, peeling and breakage of the magnet at the time of assembling and after assembling can be prevented.

As the material of the non-magnetic ring 31, a resin or a non-magnetic metal can be used as in the embodiment described later. As described above, according to this embodiment, the non-magnetic ring 31 is connected to the pole cores 11 and 21.
Prior to assembling, the plurality of permanent magnets 41 are connected and function as a holding member for holding. Since the permanent magnets 41 as a plurality of magnets are connected by the non-magnetic ring 31, the plurality of permanent magnets 41 and the non-magnetic ring 31 are connected.
Can be treated as an assembly. Therefore, the plurality of permanent magnets 41 can be handled collectively, and the plurality of permanent magnets 41 can be easily assembled between the cores 11 and 21.

FIG. 6 is a partial perspective view showing a second embodiment of the non-magnetic ring and the like according to the present invention. FIG. 7 is a view corresponding to FIG. 4 using the non-magnetic ring of FIG. It is a longitudinal cross-sectional view. The components having the same functions as those of the above-described embodiment will be described with the same reference numerals. The non-magnetic ring 31 is formed of resin, and the permanent magnet 41 is insert-molded.

Here, the outer peripheral portion 34 of the nonmagnetic ring 31
If there is a portion larger than the outer diameter surface of the claw portions 12 and 22 of the pole cores 11 and 21, the portion is cut or the like to minimize irregularities, and is substantially the same as the outer diameter surface of the claw portions 12 and 22. By using a radial surface, the effect of reducing wind noise can be increased. As described above, the permanent magnet 41 as a magnet may be insert-molded on the nonmagnetic ring 31 as the magnet holding member, and the permanent magnet 41 may be mounted on the nonmagnetic ring 31.

FIG. 8 is a partial sectional view showing a third embodiment of a non-magnetic ring or the like to which the present invention is applied. In the present embodiment, the permanent magnet 41 is disposed in direct contact with the claw portions 12 and 22 of the pole cores 11 and 21 so as to fill the gap between the side surfaces 13 and 23. The nonmagnetic ring 31 is provided with the claw portion 1.
2, 22 are formed so as to contact the side surfaces 13, 23 and the inner side surfaces 14, 24.

The nonmagnetic ring 31 has a spring effect so that the permanent magnet 41 is always sandwiched between the side surfaces 13 and 23 of the claw portions 12 and 22 in a state where a pressing force is generated. With such a configuration, the same effect as in the above-described embodiment can be obtained. FIG. 9 is a partial longitudinal section showing a fourth embodiment of the nonmagnetic ring and the like according to the present invention.

When the nonmagnetic ring 31 is formed of a nonmagnetic metal and the permanent magnet 41 is formed of a metal magnet, the permanent magnet 4 disposed on the inner side surface 35 of the nonmagnetic ring 31 is used.
At least a part of the contact surface of the peripheral surface 1 with the nonmagnetic ring 31 is integrally formed with a buffer member 42 or an adhesive material interposed between the nonmagnetic ring 31 and the permanent magnet 41. There is no interference, and the same effect as in the above embodiment can be obtained. As described above, a non-magnetic metal can be used as the magnet holding member, and an adhesive may be used to mount the magnet on the magnet holding member.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration of a rotor of an automotive alternator according to a specific embodiment of the present invention.

FIG. 2 is a partial perspective view showing a state where a pair of pole cores, a nonmagnetic ring, and a permanent magnet are assembled.

FIG. 3 is a partial perspective view showing a nonmagnetic ring in which a permanent magnet is provided on an inner surface.

FIG. 4 is a partial longitudinal sectional view taken along the line IV-IV in FIG. 2;

FIG. 5 is an explanatory diagram showing a relationship between a rotation speed and an output current depending on the presence or absence of a permanent magnet.

FIG. 6 shows a second example of the nonmagnetic ring or the like according to the present invention.
FIG. 3 is a partial perspective view showing the embodiment of FIG.

FIG. 7 is a partial longitudinal sectional view corresponding to FIG. 4 using the nonmagnetic ring of FIG. 6;

FIG. 8 is a third view of a non-magnetic ring or the like according to the present invention;
FIG. 4 is a partial longitudinal sectional view showing the example of FIG.

FIG. 9 is a view showing a fourth example of the nonmagnetic ring and the like according to the present invention;
FIG. 4 is a partial longitudinal sectional view showing the example of FIG.

[Explanation of symbols]

 Reference Signs List 10 Rotor of vehicle alternator 11, 21 Pole core (core) 12, 22 Claw (magnetic pole) 31 Nonmagnetic ring (magnet holding member) 41 Permanent magnet (magnet) 45 Field coil 46 Shaft 48, 49 Fan

Claims (12)

[Claims] 1. An alternator comprising a field coil for exciting a core of a rotor, comprising: a plurality of magnets provided on the core, each of the magnets being independent of each other; An alternator comprising: the magnet and a magnet holding member mounted on the core. 2. The magnet holding member, comprising: a plurality of holding portions provided for each of the magnets and holding the magnet; and a connecting portion connecting between the plurality of holding portions. 2. The alternator according to 1. 3. The alternator according to claim 1, wherein the magnet holding member is a non-magnetic metal. 4. The alternator according to claim 1, wherein the magnet holding member is made of a resin. 5. The alternator according to claim 4, wherein said magnet is insert-molded in said resin. 6. The alternator according to claim 1, wherein the magnet is a permanent magnet. 7. The pole core having a plurality of claws, wherein the magnet holding member is disposed in contact with a root of an inner surface of the claws.
7. The alternator according to any one of claims 1 to 6. 8. The pole core having a plurality of claws, wherein the magnet holding member is disposed along a root from an end of the claw on an inner surface of the claw. The alternator according to any one of claims 1 to 7. 9. The alternator according to claim 1, wherein the magnet holding member connects all of the plurality of magnets. 10. A method for manufacturing an alternator having a field coil for exciting a rotor core, wherein a plurality of independent magnets are connected by a magnet holding member to form an assembly. A method for manufacturing an alternator, comprising: mounting an assembly on the core. 11. The assembly according to claim 10, wherein said magnet is mounted on said magnet holding portion of a magnet holding member having a plurality of magnet holding portions connected by a connecting portion. How to make a generator. 12. The method according to claim 10, wherein the assembly is formed by insert molding a plurality of the magnets.