JPH0739094A - Rotor of magnet generator and its manufacture - Google Patents

Abstract

PURPOSE:To fix magnets without using a magnet case and facilitate the reduction of dimensions of an axial direction. CONSTITUTION:First swollen parts 37 are formed between adjacent magnets by swelling the cylindrical wall of a cover outward radially to fix the magnets in the radial direction. As for the fixing in the axial direction, the outer flange 32 of the cover 30 is pressed against the upper planes of the respective magnets 20 and, in this state, the bottom part of the cylindrical wall 31 of the cover 30 is swollen outward radially to form second swollen parts 38 so as to fix the respective magnets 20 between the outer flange part 32 of the cover 30 and the bottom part of the cover cylindrical wall. Therefore, the heights of the respective magnets 20 are made to be uniform by the outer flange part 32 of the cover 30 and the dimensional variation of the height direction of the respective magnets 20 are absorbed respectively by the blocking wall 14 side of a yoke 11, so that the axial length of the rotor of a magnet generator can be reduced. As a magnet case can be eliminated, the number of components and the working man-hours can be saved and the severity of the dimensional control of the magnet can be relieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a magnet generator, and more particularly to improvement of a permanent magnet fixing structure, for example, rotation of a magnet generator mounted on a small or special vehicle such as a motorcycle or a buggy. Regarding what is effective for children.

[0002]

2. Description of the Related Art Generally, in a small or special vehicle such as a motorcycle or a buggy, a magnet generator using a permanent magnet (hereinafter referred to as a magnet) such as a ferrite magnet may be used.

In this type of magnet generator, a rotor is constructed by arranging and fixing a plurality of magnets at equal intervals on the inner circumference of a yoke, and coils are wound around a plurality of radial portions of a core. The rotor is driven by an engine to rotate around the electron emitter, so that an electromotive force is induced in each magnetic pole coil of the electron emitter. ing.

Conventionally, as a rotor used in such a magneto-generator, a case is formed in which a plurality of magnet accommodating chambers each having a shape corresponding to a magnet are formed by annularly connecting an upper open frame into a yoke. The magnet is inserted into each of the housing chambers of the case, and is clamped and fixed between the partition walls between the adjacent housing chambers,
Further, a tubular cover is fitted inside the case and the magnet, and a resin pressing ring is brought into contact with the outer flange portion of the cover, and then the winding and crimping margin portion formed on the outer periphery of the upper end portion of the yoke is removed. There is one in which a plurality of magnets are integrated with a yoke by winding and crimping on a pressing ring.

Further, as rotors of conventional magnet generators of this type, there are those disclosed in JP-A-60-187248 and JP-A-61-280747.

The rotor of the former magnet generator is composed of an iron bowl, a magnet mounted on the inner circumference of the iron bowl, a magnet protection cover arranged on the inner circumferential surface of the magnet, a bottom surface of the iron bowl, the magnet and the magnet. It is provided with an adhesive reservoir space formed by the protective cover, an adhesive injection hole provided on the bottom surface of the iron bowl between the inner peripheral surface of the iron bowl and the magnet protective cover.

In the rotor of the latter magnet generator, the cylindrical portion of the magnet protection member is pressed against the inner peripheral surface of a plurality of arc-shaped magnets arranged on the inner peripheral surface of the iron bowl, and the flange of this magnet protective member is pressed. Part of the magnet to abut the end face of the magnet on the opening end side to regulate the axial movement of each magnet, and to fix the fixed part of the magnet protection member to the bottom of the iron bowl, and to fix the iron bowl of the cylindrical part of the magnet protection member. The outer shape of the bottom side is tapered so that it is smaller than the inner diameter of each magnet array, and a bulging portion that bulges outward in the space between the magnets is formed in the cylindrical portion of the magnet protection member. By
By fixing the magnet protection member to the iron bowl, each magnet is firmly fixed to the inner circumferential surface of the iron bowl. In addition, the bulging portion absorbs the deformation of the magnet protection member when the magnet protection member is press-fitted, and the outer shape of the fixed portion side of the cylindrical portion of the magnet protection member is smaller than the inner diameter of each magnet array. With this configuration, the deformation of the magnet protection member on the side of the fixed portion is reduced, and the magnet protection member can be reliably fixed to the iron bowl by the fixed portion.

[0008]

However, in the rotor of the conventional magnet generator in which the magnet case is used, not only the number of parts and the number of assembling steps are increased due to the magnet case, but the magnet is magnetized. Since it is press-fitted into the case, strict control of the magnet dimensions is required.Also, allowance for absorbing dimensional variations of the magnet, magnet case and coiling allowance, and the axial direction of the rotor of the magnet generator. The dimension of becomes longer.

Further, in the rotor of the magnet generator and the manufacturing method thereof proposed in Japanese Patent Laid-Open No. 60-187248, since an adhesive is used, workability is deteriorated.

Further, in both of the rotors of the magnet generator proposed in Japanese Patent Laid-Open No. 60-187248 and Japanese Patent Laid-Open No. 61-280747, the axial positioning of each magnet is the bottom of the iron bowl. Since it is performed on the wall side, variations in the axial dimension of each magnet are absorbed on the opening side of the iron bowl, and as a result, the axial dimension of the rotor of the magnet generator becomes long. In order to store the generator coil of the magnet generator in the restricted space inside the yoke of the rotor, the stator core is positioned on the opening side of the yoke that absorbs the variation in the axial dimension of each magnet. However, the variation in the output of the generator also becomes large.

It is an object of the present invention to fix a magnet without using a magnet case and an adhesive, and to reduce the axial dimension as much as possible, and a rotor for a magnet generator and its manufacture. To provide a method.

[0012]

In the rotor of the magneto-generator according to the present invention, a plurality of magnets are arranged at intervals on the inner circumference of a substantially bowl-shaped yoke, and a cylindrical shape is formed inside the magnet. In the rotor of the magneto generator in which the cover of FIG. 2 is fitted, the first bulge formed by bulging the tubular wall of the cover outward in the radial direction has a length in the magnet axial direction in the space between the adjacent magnets. An outer flange portion formed over the entire length and radially outwardly protruding on the yoke opening side of the cover is in contact with the yoke opening side end surface of each magnet, and the yoke of the cover is also formed. The inner flange portion that projects radially inward on the closing wall side is fixed to the yoke closing wall, and the cylindrical wall of the cover is placed in the space between the yoke closing wall and the end surface of the magnet on the yoke closing surface side. Outward of at least each magnet Wherein the second expanded portion formed by bulging in over click closed side end surface is provided.

[0013]

According to the above-mentioned means, while the outer flange portion of the cover is in contact with the upper surface of each magnet, the yoke closing wall side portion of the cylindrical wall of the cover is bulged outward in the radial direction. The magnets can be fixed in a state of being sandwiched by the outer flange portion of the cover and the second bulging portion bulged and molded on the yoke closing wall portion of the cover cylinder wall. As a result, the axial positions of the magnets are aligned on the outer collar portion of the cover, and the dimensional variations in the height direction of the magnets are absorbed on the closed wall side of the yoke. The axial length of the rotor can be shortened.

[0014]

FIG. 1 shows a rotor of a magneto-generator which is an embodiment of the present invention. (A) is a plan view, (b) is (a).
3 is a front cross-sectional view taken along line bb of FIG. FIG. 2 shows a yoke, (a) is a partially omitted plan view, (b) is a front sectional view taken along the line bb of (a), and (c) is a partially omitted bottom view. FIG. 3 shows a cover, (a) is a partially omitted plan view, (b) is a front sectional view, and (c) is a partially omitted bottom view. FIG. 4 and subsequent drawings are explanations of a method for manufacturing a magneto-generator which is an embodiment of the present invention.

In the present embodiment, the rotor of the magneto-generator according to the present invention comprises a yoke, a plurality of magnets and a cover.

The yoke 11 is integrally formed in a substantially bowl shape whose upper surface is opened and whose lower surface is closed by a magnetic material. A reluctor 13 has a cylindrical wall 12 having a predetermined width in the circumferential direction and the axial direction. Projected outward in the direction. A shaft hole 15 for inserting a boss (not shown) directly connected to the engine is formed in the lower surface blocking wall 14 of the yoke 11 at the center, and a yoke positioning described later is provided at a position outside the shaft hole 15. Circular hole used to attach jig 1
A pair of 6 are provided on the concentric circles with a phase difference of 180 degrees. In addition, the closing wall 1 of the yoke 11
A plurality of elliptical holes 17 (12 in the present embodiment) for inserting a magnet positioning jig, which will be described later, are formed in the outer peripheral portion of No. 4 on the concentric circles at equal intervals in the circumferential direction. There is.

Further, the bottom surface of the closing wall 14 of the yoke 11 is provided with a plurality of convex portions 18 (8 in this embodiment) for fixing the cover, and a group of circular holes 16 and a group of elliptical holes 17 are provided. They are arranged at equal intervals in the circumferential direction on concentric circles between them, and a part of the closing wall 14 is pushed up from the outer surface so as to project inward in the axial direction. This convex portion 18 covers the cover as will be described later. It is configured so that it can be caulked by being inserted into a fixing hole that is provided so as to project.

The closed wall 14 of the yoke 11 is provided with a plurality of female screw holes 19 for attaching a cooling fan, which are concentrically formed around the group of circular holes 16 at equal intervals in the circumferential direction. Further, no winding and crimping margin is provided on the opening edge of the cylindrical wall 12 of the yoke 11.

The magnet 20 has a height equal to or less than the depth of the yoke 11 and is integrally formed into a substantially rectangular parallelepiped having a circular arc shape curved along the inner circumference of the yoke 11 in the width direction. Inclined surface portions 23 are formed on both left and right ends of an arc-shaped inner peripheral surface (hereinafter, referred to as abdominal surface) 21 of the magnet 20 so as to approach an outer peripheral surface (hereinafter, referred to as a rear surface) 22 as they go to the left and right end portions. Has been done. The rising side surfaces 24 and 24 on both sides are formed so as to be at right angles to the tangent to the normal line passing through the center of the yoke 11, and the upper surface 25 and the lower surface 26 are formed parallel to each other.

The cover 30 is made of a metal material such as a thin iron plate and is integrally formed by drawing and pressing. The cover 30 is formed into a cylindrical shape which is press-fitted into a cylinder formed by a magnet 20 group described later. An outer flange portion 32 is formed at one end (hereinafter, referred to as an upper end) of the cylindrical wall 31 of the cover 30 in a circular donut shape protruding outward in the radial direction.

Before assembling, an inner collar portion 33 is integrally formed in a circular donut shape at the lower end of the cylindrical wall 31 of the cover 30. The inner diameter of the inner flange portion 33 is smaller than the arrangement diameter of the group of convex portions 18 arranged on the yoke 11 and equal to or slightly larger than the arrangement diameter of the circular holes 16, 16. In the radial middle portion of the inner flange portion 33, the same number of fixing holes 34 as the convex portions 18 group of the yoke 11 (8 in this embodiment) are arranged so that each of them is aligned with the convex portion 18 group of the yoke 11. It is opened in each of the fixing holes 34
Are formed so that the respective convex portions 18 can be inserted respectively.

A notch 3 is formed on the inner peripheral edge of the inner flange 33.
A plurality of (5 in this embodiment) 5 are formed in a substantially semi-circular shape, and the yoke 1 is formed by the group of the notches 35.
One group of circular holes 16 and one group of female screw holes 19 can be appropriately escaped. Further, a rigidity-imparting portion 36 is formed by bending and bending over the entire circumference including the cutout portion 35 at the inner peripheral edge of the inner flange portion 33. The rigidity imparting portion 36 is formed by bending the inner peripheral edge portion of the inner collar portion 33 inward in the axial direction to a constant height over the entire circumference by drawing or the like, and imparts sufficient rigidity when the cover 30 described later is press-fitted. It is like this.

Next, a method of manufacturing the rotor of the magneto-generator, which is an embodiment of the present invention, will be described in the case of using each component having the above-mentioned configuration. This description will clarify the details of the configuration of the rotor of the magneto-generator that is an embodiment of the present invention.

First, as shown in FIGS. 4A and 5, the yoke 11 is set on the base 41 of the manufacturing apparatus 40 for the rotor of the magnet generator. At this time, the yoke 1
A pair of yoke positioning jigs 42, 42 are respectively inserted into the pair of circular holes 16, 16 in FIG. Also,
A magnet circumferential positioning jig (hereinafter, referred to as a magnet first jig) 43 and a magnet axial support jig (hereinafter, referred to as a magnet second jig) 44 are inserted into the oval holes 17 group. It

Here, the second magnet jig group 44 is floatingly supported on the base 41 by springs 45, respectively, and is movable in the vertical direction. The magnet first jig 43 group is the magnet 20.
The same number (4 in this embodiment) as the elliptical holes 17
They are arranged at equal intervals in the circumferential direction on a circle concentric with the array diameter of the group. Further, shoulders 43a, 43a are formed on both side edges in the circumferential direction of each magnet first jig 43, respectively. The other magnet second jig 44 group has an oval hole 17
The number (8 in this embodiment) obtained by subtracting the number of magnets 20 from the number of groups is arranged on both sides of each first jig 43 concentrically with the array diameter of the group of elliptical holes 17. ing.

Subsequently, as shown in FIGS. 4A and 5, a plurality (four in this embodiment) of magnets 20 are arranged in a circular ring shape in the yoke 11. At this time, the bottom surface 26 of the magnet 20 is placed on each of the two second jigs 44 with the back surface 22 being in contact with the inner peripheral surface of the yoke 11, and both side surfaces 2 are
4, 24 are shoulders 43a, 4 of the first jigs 43, 43 on both sides.
3a, respectively. In this state, the magnet 20 is positioned in the circumferential direction by the first jig 43. Further, the magnet 20 is positioned at the upper limit by the second jigs 44, 44 and is in a state of being floatingly supported in the vertical direction.

Next, as shown in FIGS. 4A and 6, the cover 30 is fitted inside the group of magnets 20 by the fitting tool 50. At this time, since the rigidity imparting portion 36 is formed on the inner flange portion 33 of the cover 30, the cover 30 is properly fitted. In the state after the fitting, the cover 30 has the inner flange portion 33 with the closing wall 14 of the yoke 11.
Is in contact with the bottom surface of the magnet, and the outer flange portion 32 is in contact with the upper surface 25 of the magnet group 20. Further, when the cover 30 is press-fitted, the first bulging portion 37 is formed between the magnets 20 group, and the magnets 20 group is relatively positioned in the circumferential direction and prevented from rotating.

Here, the outer diameter of the fitting tool 50 is formed in a two-step cylindrical shape having a small diameter on the lower side and a large diameter on the upper side, and the small diameter portion 51 on the lower side is substantially the same as the inner diameter of the cylindrical wall 31 of the cover 30. The diameter of the large-diameter portion 52 on the upper side is substantially the same as the outer diameter of the outer collar portion 32 of the cover 30.

The fitting tool 50 has the same number of yoke positioning holes 53 as the circular holes 16 (two holes in this embodiment), which are provided in the axial direction. The yoke positioning jigs 42 are relatively inserted into the respective yoke positioning holes 53, so that the fitting tool 50, the yoke 11 and the magnet 20 group are positioned with respect to each other.

In the fitting tool 50, the same number of insertion holes 54 as the projections 18 of the yoke 11 (8 in this embodiment) are provided in the axial direction. Further, an annular groove 55 is recessed in the lower surface of the small diameter portion 51 of the fitting tool 50 so as to accommodate the rigidity imparting portion 36 of the cover 30. According to the above-described positioning state, the protrusions 18 are inserted into the insertion holes 54, and the rigidity imparting portion 36 is inserted into the annular groove 55, respectively, and the fitting tool 50 to the protrusions 18 and the rigidity imparting portion 36 is inserted. Interference has been avoided.

As shown in FIGS. 4 (b) and 7, the caulking pin is inserted through the insertion hole 54 of the fitting 50 and the yoke 11 inserted through the fixing hole 34 of the cover 30.
The protruding end of the convex portion 18 is caulked. The group of protrusions 18 after the caulking process causes the cover 30 to be fixed in a circular ring shape to the closing wall 14 of the yoke 11 over the entire circumference of the inner flange portion 33, and thereafter, the fitting tool 50.
Is dismantled. In this state, the magnet group 20 is circumferentially positioned and prevented from rotating with respect to the yoke 11.

Next, after the fitting tool is removed, FIG.
As shown in FIG. 8C and FIG. 8, the plastic tool 60 is inserted inside the cover 30 to form a space between the yoke closing wall of the cylindrical wall 31 of the cover 30 and the yoke closing wall side end surface portion of the magnet. A second swelling portion 38 is formed so as to bulge outward in a ring shape, or at least on the yoke closing surface side end surface portion of each magnet, and the magnets 20 are positioned in the axial direction.

Here, the outer diameter of the plastic tool 60 is formed in a two-step cylindrical shape with a small diameter on the lower side and a large diameter on the upper side, and the small diameter portion 61 on the lower side is the inner diameter of the cylindrical portion 31 of the cover 30. The large diameter portion 62 on the upper side is formed to have substantially the same diameter as the outer diameter of the outer flange portion 32 of the cover 30.

In the plastic tool 60, the same number of yoke positioning holes 63 as the circular holes 16 (two holes in this embodiment) are provided in the axial direction. Each yoke positioning hole 63
The respective positioning jigs 42 for the yokes are relatively inserted into each other, whereby the positioning of the plastic tool 60, the yoke 11 and the magnet 20 group is ensured.

An elastic body portion 64 of urethane resin or the like is provided on the lower surface of the small diameter portion 61 of the plastic tool 60. The elastic body portion 64 includes the lower surface of the small diameter portion 61 of the plastic tool 60 and the closing wall 14 of the yoke 11. When compressed in the axial direction between them, they are formed so as to be able to bulge and deform outward in the radial direction all around, or at least at the yoke closing wall side end surface portion of each magnet.

When the elastic body portion 64 of the plastic tool 60 is pressed against the bottom surface of the closing wall 14 of the yoke 11, the elastic body portion 64 bulges and deforms outward in the radial direction, so that the inner collar portion of the cylindrical wall 31 of the cover 30 is deformed. Extrude the area around 33 radially outward,
The second bulging portion 38 of the magnet is formed in the space between the yoke closing wall and the yoke closing wall side end surface portion of the magnet.

When the second bulging portion 38 of the cover 30 is bulged, the lower surface of the large diameter portion 62 of the plastic tool 60 pushes down the outer flange portion 32 of the cover 30, so that the second bulging portion 3 is formed.
8 does not have to be formed by locally extending the cylindrical wall 31 of the cover 30, but is formed with a surplus of the pressed cylindrical wall 31. Therefore, due to the bulging of the second bulging portion 38, the strength of the second bulging portion does not decrease due to an extreme reduction in plate thickness.

On the other hand, when the lower surface of the outer flange portion 32 of the pushed down cover 30 contacts the upper surface 25 of each magnet 20, each magnet 20 is pushed upward by each second magnet jig 44. Since the magnets 20 are floatingly supported, the height of each magnet 20 is the lower surface of the outer collar portion 32 of the cover 30, that is, the plastic tool 60.
The large-diameter portion 62 has a leveled lower surface.

Then, when the plastic tool 60 is inserted with a certain size and the compression of the elastic body portion 64 in the axial direction is stopped, the heights of the magnets 20 are aligned with the lower surface of the outer flange portion 32 of the cover 30. The outer flange portion 32 and the second bulge portion 3 in the closed state.
It will be clamped between 8 and 8 and fixed.

After that, the plastic tool 60 is extracted upward from the inside of the cover 30. Next, the yoke 11 is the base 4
1 Reset from above. Through the above steps, the rotor of the magneto generator shown in FIG. 1 is manufactured.

[0041]

As described above, according to the present invention,
The following effects are obtained. (1) A first bulge portion formed by bulging a tubular wall of the cover outward in the radial direction is formed between adjacent magnets, and the magnets are fixed in the radial direction, while each magnet is axially fixed. With the outer flange part of the cover in contact with the upper surface, the yoke blocking wall side part of the cover's cylinder wall is bulged outward in the radial direction, so that each magnet is covered with the outer flange part of the cover and the cover cylinder wall. It can be fixed in a state of being sandwiched by the second bulging portion that is bulged and formed on the yoke closing wall side portion.

(2) According to the above (1), the height positions of the magnets are aligned on the outer flange portion of the cover, and the dimensional variations in the height direction of the magnets are absorbed on the closing wall side of the yoke. Therefore, the axial length of the rotor of the magneto generator can be shortened.

(3) According to the above (1), since the magnet case can be eliminated, the number of parts and the number of work steps can be reduced, and the step of press-fitting the magnet into the magnet case is eliminated. The strictness of the dimensional control of the magnet can be eased. Further, the axial length of the rotor of the magneto generator can be shortened by the amount by which the pressing ring is eliminated.

(4) According to the above (1), since the winding and crimping margin portion at the opening end of the yoke can be omitted, the axial length of the rotor of the magnet generator can be further shortened.

(5) Since the positions (2), (3) and (4) of the rotor of the magneto generator in the axial direction of the magnet and the position of the magnet core in the magnet axial direction can be kept constant, It is possible to suppress variations in the performance of the magneto generator.

(6) By pressing the cover into the magnet group while temporarily positioning the magnet on the yoke with the jig, the press-fitting of the cover can be stabilized.

(7) When the bottom portion of the cover's cylinder wall is bulged outward in the radial direction, the cover is pushed down and the bulging margin is supplied from above, whereby excessive pulling is applied to a part of the cover cylinder wall. Since it is possible to prevent the stress from acting, it is possible to prevent the strength of the second bulging portion of the cover from being significantly reduced.

[Brief description of drawings]

FIG. 1 shows a rotor of a magneto-generator which is an embodiment of the present invention, (a) is a plan view, (b) is (b) -b of (a).
It is a front sectional view which follows a line.

FIG. 2 shows a yoke, (a) is a partially omitted plan view, (b) is a front sectional view taken along line bb of (a),
(C) is a partially omitted bottom view.

FIG. 3 shows a cover, (a) is a partially omitted plan view, (b) is a front sectional view, and (c) is a partially omitted bottom view.

4A and 4B show a method of manufacturing a magneto-generator according to an embodiment of the present invention, in which FIG. 4A is a partially cut exploded perspective view showing a cover inserting step, and FIG. 4B shows a cover fixing step. Partially cut perspective view, (c) is a partially cut perspective view showing the cover bulging step.

FIG. 5 is an enlarged partial front sectional view showing a magnet positioning step.

FIG. 6 is an enlarged partial front sectional view showing a cover inserting step.

FIG. 7 is a front sectional view showing a fixing step of the cover.

FIG. 8 is a front sectional view showing a cover bulging step.

[Explanation of symbols]

11 ... Yoke, 12 ... Cylindrical wall, 13 ... Reactor, 14 ... Closure wall, 15 ... Shaft hole, 16 ... Circular hole, 17 ... Elliptical hole, 18
... Convex part, 19 ... Female screw hole, 20 ... Magnet, 21 ... Arc-shaped inner peripheral surface (abdominal surface), 22 ... Outward surface (back surface), 23
... inclined surface portion, 24 ... rising side surface, 25 ... upper surface, 26
... Lower surface, 30 ... Cover, 31 ... Cylinder wall, 32 ... Outer collar part,
33 ... Lower collar part, 34 ... Fixing hole, 35 ... Notch part, 36 ...
Stiffness imparting part, 37 ... First bulging part, 38 ... Second bulging part, 40 ... Manufacturing device for rotor of magnet generator and manufacturing method thereof, 41 ... Base, 42 ... Yoke positioning jig, 4
3 ... Magnet circumferential positioning jig (1st for magnet
Jig), 43a ... Shoulder, 44 ... Magnet axial direction setting jig (second jig for magnet), 45 ... Spring, 5
0 ... Fitting tool, 51 ... Small diameter part, 52 ... Large diameter part, 53 ... Yoke positioning hole, 54 ... Insertion hole, 55 ... Annular groove, 60 ... Plastic tool, 61 ... Small diameter part, 62 ... Large diameter part, 63 ... Yoke positioning hole, 64 ... Elastic body portion.

Claims (2)

[Claims] 1. A rotor of a magneto-generator, wherein a plurality of magnets are arranged at intervals on an inner circumference of a substantially bowl-shaped yoke, and a cylindrical cover is fitted inside the magnet. 1st which bulges the cylinder wall of a cover to radial direction outward
Is formed over the entire length in the axial direction of the magnet in the space between the adjacent magnets, and the outer flange portion projecting outward in the radial direction on the yoke opening side of the cover is provided on each of the magnets. An inner collar portion that is in contact with the end surface of the yoke opening side and that projects radially inward on the yoke closing wall side of the cover is fixed to the yoke closing wall, and the cylindrical wall of the cover is fixed. A second bulging portion bulged outward at least at the yoke closing surface side end surface portion of each magnet is provided in a space between the yoke closing wall and the yoke closing surface side end surface of the magnet. And the rotor of the magnet generator. 2. The method of manufacturing a rotor for a magneto generator according to claim 1, wherein a step of inserting a jig from the outside of the closing wall into a through hole that is previously opened in the closing wall of the yoke; A step of accommodating a plurality of magnets and placing them on the jig respectively; and by inserting a cover inside the magnet group, the cylindrical wall of the cover bulges radially outward, A step of forming a first bulge in a space between adjacent magnets; a step of fixing the inner flange of the cover to a closing wall of the yoke; A step of outwardly bulging at least at the yoke closing wall side end surface portion of each magnet to form a second bulging portion in a space between the yoke closing surface side end surface. Method for manufacturing a rotor of a magnet generator.