JPH0524736B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotor of a magnet generator, and in particular,
This relates to the improvement of rotors in which the rotor also serves as a flywheel, such as the rotor of flywheel magnetos used in relatively high-speed rotation areas such as small vehicles such as motorcycles or special vehicles such as racing cars and buggies. Concerning what is effective when used.

[Conventional technology]

As a conventional flywheel magnet, a plurality of magnets are arranged in an annular shape on the inner peripheral surface of a yoke that is formed in a substantially bottomed cylindrical shape.
A rotor in which these magnets are fixed by a winding caulking part formed on the green side of the opening of the yoke is arranged around the generator, and this rotor is driven by the engine and rotates around the generator. Therefore, some generators are configured to induce an electromotive force in each magnetic pole coil of the generator.

[Problem to be solved by the invention]

In the rotor of such a flywheel magnet, the yoke receives a combined force of the centrifugal force due to its own weight and the centrifugal force due to the weight of the magnet during rotation, but the bottomed side of the cylindrical wall of the yoke is While the yoke is supported to ensure sufficient centrifugal strength, the open end of the yoke is not supported due to the winding and caulking margin, so it is more susceptible to outward movement due to centrifugal force than the bottomed side. The inventors have discovered that there is a problem in that the bulge deformation increases as the rotation speed increases.

An object of the present invention is to provide a rotor for a magnet generator that can prevent bulging deformation in a high-speed rotation region.

[Means to solve the problem]

The rotor of a magnet generator according to the present invention is a rotor of a magnet generator in which a plurality of magnets 12 are arranged and fixed in an annular manner on the inner circumferential surface of a yoke 11 which also serves as a flywheel. , a first cylindrical body 11a and a second cylindrical body 11b each having the same diameter and formed by drawing into a cylindrical shape having an open end at one end and a bottom wall at the other end at least partially at the inner periphery. It is equipped with a first cylindrical body 11a and a second cylindrical body 11a.
The cylindrical bodies 11b are joined by a joining part 20 with their open end surfaces abutted against each other, and a case 13 integrally formed using a non-magnetic material is fitted into the yoke 11. Reference numeral 13 indicates a plurality of partition walls 3 on one end surface of the ring 33.
5 are arranged upright in the axial direction at intervals in the circumferential direction, and the height of each partition wall portion 35 is formed to be lower than the height of the magnet 12, and each partition wall portion 35 Each of the magnets 12 is inserted between the case 13 and a cover 1 made of a magnetic metal material and formed into a cylindrical shape with a flange.
4 is fitted so as to cover the group of magnets 12, and a retaining ring 15 formed in a ring shape using a non-magnetic material is placed on the flange of the cover 14.
is applied, and the bottom wall of the second cylindrical portion 11b presses the case 13 and the group of magnets 12 toward the bottom wall of the first cylindrical portion 11a via the retaining ring 15 and the flange of the cover 14. It is characterized by

[Effect]

According to the above-mentioned means, since the yoke is formed by joining a pair of substantially bottomed cylindrical bodies, the mechanical rigidity at both ends of the yoke becomes substantially equal, and as a result, the mechanical rigidity at both ends of the yoke due to centrifugal force is reduced. The outward bulging deformation is effectively suppressed.

〔Example〕

Fig. 1 is a longitudinal cross-sectional view showing a rotor of a flywheel magneto according to an embodiment of the present invention, Fig. 2 is a partially omitted partially cutaway plan view, and Fig. 3 is an enlarged partial cross-section of Fig. 1. It is a diagram.

In this embodiment, the rotor of the flywheel magneto is a yoke 11 that also serves as a flywheel.
, a plurality of magnets 12 disposed on the inner periphery of the yoke 11, a case 13 for positioning and fixing the magnets 12, a cover 14 for protecting the magnets 12, and a holding ring 15. .

The yoke 11 includes a pair of first cylindrical body 11a and second cylindrical body 11b that are formed in substantially the same shape, and the first cylindrical body 11a is made of a magnetic material such as structural steel. By deep drawing, it is integrally formed into a substantially cylindrical shape with one end surface (hereinafter referred to as the top surface) open and the bottom surface closed. The lower closed wall of the first cylindrical body 11a has a shaft hole 16 for inserting a boss (not shown) directly connected to the engine, and a plurality of attachment holes 17 for connecting the rotor to the boss. They are bored at positions outside the shaft hole 16, respectively.
A plurality of protrusions 18 for preventing rotation of the case 13 are protruded from the outside of the mounting hole 17 by pushing up the lower closing wall from the outside, and the mounting hole 17 and the protrusions 18 can be arranged at arbitrary positions. arranged circumferentially at an angle.

Second cylindrical body 11b forming the upper part of yoke 11
is integrally molded in substantially the same shape as the first cylindrical body 11a using the same material as the first cylindrical body 11a and by the same means, and window holes 19 are arranged concentrically in the closing wall of the first cylindrical body 11a, and the outside It has been opened in a large area, leaving the surrounding area intact. The first cylindrical body 11a and the second cylindrical body 11b
are made to be face-to-face with each other, and their joint surfaces are integrally joined around the entire circumference by a joint 20 formed by a suitable means such as welding,
It constitutes a yoke 11.

The magnet 12 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 inside of the yoke 11 in the width direction.

The case 13 is integrally molded using a non-magnetic material having appropriate elasticity such as resin.
A plurality of partition wall portions 35 are arranged at equal intervals in the circumferential direction on one end surface of a ring 33 formed in a substantially circular ring shape, and are respectively erected in the axial direction. It is formed into a substantially cylindrical shape. A plurality of partition walls 3 in the case 13
In the cylindrical wall 30 that is virtually formed by lining up the partition walls 35 in the circumferential direction, there are a plurality of storage chambers 31, which are spaces formed between adjacent partition wall parts 35, 35, arranged in the circumferential direction with substantially equal phase difference. They are arranged and formed respectively. The partition wall portion 35 is formed into a columnar shape having a height less than or equal to the height of the magnet 12 and a width slightly larger than the width of the magnet 12. The floor wall portions 32 of each storage chamber 31 are adjacent to each other to form a series of rings 33 . A plurality of recesses 34 are sunk in the lower surface of the ring 33, and each recess 34 is formed to fit into the projection 18 of the yoke 11. Holding parts 36 are disposed on both sides of the partition wall 35 in the circumferential direction, and are formed to protrude in a substantially tangential direction (perpendicular to the normal line passing through the center of the partition wall in the circumferential direction). .

The cover 14 is integrally formed by drawing press using a magnetic metal material such as a thin iron plate, and has a generally cylindrical shape that fits inside the case 13 as a whole. The holding ring 15 is attached to the case 1.
It is integrally molded using the same material as the case 13 into a circular ring shape that is approximately the same as the case 13.

Next, the assembly work of each of the above-mentioned parts will be explained.

First cylindrical body 1 before being assembled into yoke 11
A case 13 is fitted into 1a, and the first cylindrical body 11
Case 1 is attached to each convex portion 18 raised on the bottom wall of a.
3, each of the recesses 34 on the lower surface is fitted. By fitting the convex portion 18 and the concave portion 34, the case 13
is prevented from rotating integrally with the yoke 11.

Subsequently, the magnets 12 are press-fitted into each housing chamber 31 of the case 13 from above. When the magnet 12 is strongly pushed into the storage chamber 31, the holding part 36 protruding from the side surface of the partition wall 35 is pushed so strongly that it is crushed by the side surface of the magnet 12, as shown in FIG. Pressed. In this crushed state, the holding part 36 is compressed and deformed by the magnet 12 and strongly rebounds, so the magnet 12 is relatively pressed together by the holding parts 36, 36 on both sides in the accommodation chamber 31. You will be killed.

Then, inside the 12 groups of magnets which are housed and fixed in each housing chamber 31 of the case 13 and arranged in an annular shape, a cylindrical shape having an outer diameter approximately equal to the diameter of the circular inner peripheral surface of the 12 groups of magnets is formed. The cover 14 is press-fitted. Next, case 1
A presser ring 15 is placed on the upper flange of the cover 14 covering the upper end surface of the cover 3 .

Next, the second cylindrical body 11b is connected to the first cylindrical body 11a.
It is fitted into the case 13 with its sides facing each other. Subsequently, the joint surfaces of the first cylindrical body 11a and the second cylindrical body 11b are joined by suitable means such as welding, and the yoke 11 is integrally formed.

As a result, the yoke 11, the magnet 12, the case 13, the cover 14, and the holding ring 15 are caulked and integrated. That is, in this rotor, each magnet 12 is accommodated in each accommodation chamber 31 in the case 13 fitted into the yoke 11 and positioned on the inner periphery of the yoke 11, and the holding part 36 is located between the partition walls 35, 35. It is clamped and fixed by.

Next, the usage will be explained.

When the rotor rotates at high speed, the yoke 11 receives a combined force of centrifugal force due to its own weight and centrifugal force due to the weight of the magnet 12. As a result, the cylindrical wall of the yoke 11 is locally subjected to a strong centrifugal force at the position where the magnet is disposed, and tends to bulge outward at that position. Incidentally, the centrifugal force due to the weight of the case is sufficiently smaller than that of the magnet 12.

At this time, the lower part (closed wall side portion) of the cylindrical wall of the yoke is increased in rigidity by the closed wall acting like a rib, so that sufficient centrifugal force resistance is ensured. As a result, local bulging deformation of the lower portion of the cylindrical wall portion of the yoke is prevented.

On the other hand, if the upper part of the yoke's cylindrical wall is completely open, the centrifugal strength will be weaker than the lower part. If it is subjected to a strong local force at a certain position, it will bulge outward and deform.

In other words, the cylindrical wall of the yoke bulges outward in the vicinity of its opening, as shown by the imaginary line in FIG. The peak is at the center of the magnet in the circumferential direction, as shown in FIG. The amount of deformation is approximately proportional to the rotation speed of the rotor.

However, like the rotor according to the above configuration,
If the yoke 11 is integrally manufactured by joining a first cylindrical body 11a and a second cylindrical body 11b, which are each formed into a substantially bottomed cylindrical shape, facing each other, the upper part of the yoke 11 also overlaps with the lower part. It will exhibit approximately the same mechanical strength.

That is, as shown in detail in FIG. 3, the second cylindrical body 11b constituting the upper part of the yoke 11 has a circular ring-shaped inner flange portion on the outer periphery of its upper end, similar to the first cylindrical body 11a. This is because they are integrally formed.

According to this embodiment, the first cylindrical body is formed into a substantially bottomed cylindrical shape, and the second cylindrical body is formed with a circular ring-shaped inner flange, which provides rigidity in the radial direction at both ends of the yoke. By forming the ribs that raise the rotor, it is possible to suppress outward bulging deformation at both ends of the yoke during high-speed rotation, thereby increasing the rotor's high-speed rotation resistance and increasing its safety. be able to.

In other words, repeated bulging deformation of the yoke due to high-speed rotation means an increased risk of metal fatigue, but if bulging deformation is suppressed and the high-speed rotation region where it occurs becomes higher, the metal The risk of fatigue is significantly reduced.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and may be modified without departing from the gist thereof.
It goes without saying that various changes are possible.

For example, the means for joining the joint surfaces of both cylindrical bodies is not limited to welding, but may also be adhesive, caulking, or the like.

〔Effect of the invention〕

As described above, according to the present invention, the performance of the flywheel magneto can be significantly improved by allowing the rotor to be used in a high-speed rotation region.

Furthermore, compared to the case where a conventional integrated yoke is manufactured by drawing, the depth in the first and second cylindrical bodies is smaller than the depth of the yoke, so the drawing rate for the cylindrical body is relaxed. This improves the drawability and improves the material yield. As a result, compared to conventional integrated yokes, it is possible to widen the range of selection regarding the material and plate thickness during drawing processing, increase the degree of freedom in design, and further improve centrifugal strength.

Additionally, if the axial length of the rotor differs depending on the output, this can be handled by changing the second cylindrical body.
Versatility and mass productivity can be improved.

Furthermore, in the present invention, the magnet is inserted between the partition walls of the case and is attached to the yoke while being covered by the cover, so that the magnet can be fixed to the yoke while being protected by the case and the cover. It is possible to
The magnet can be fixed to the yoke without forming a deformed part such as a recess in the magnet itself. As a result, the magnet is fixed to the yoke with uniform force.

In addition, by using the case and the holding ring, it is possible to absorb the dimensional error of the first cylindrical body and the second cylindrical body with respect to the magnet, so the drawing accuracy of the first cylindrical body and the second cylindrical body is relaxed. be able to.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing a rotor of a flywheel magneto according to an embodiment of the present invention, Fig. 2 is a partly omitted partially cutaway plan view thereof, and Fig. 3 is an enlarged partial cross-section of Fig. 1. It is a diagram. 11...Yoke, 12...Magnet, 13...
... Case, 14 ... Cover, 15 ... Holding ring, 16 ... Shaft hole, 17 ... Mounting hole, 18 ...
...Protrusion, 19...Window hole, 20...Joining part, 30...
... Cylinder wall, 31 ... Accommodation chamber, 32 ... Bottom wall, 3
3...Ring, 34...Recess, 35...Partition part,
36... Holding part.

Claims (1)

[Scope of Claims] 1. In a rotor of a magnet generator in which a plurality of magnets 12 are arranged and fixed in an annular manner on the inner peripheral surface of a yoke 11 which also serves as a flywheel, the yokes 11 have equal diameters. , a first cylindrical body 11a and a second cylindrical body 11b each formed by drawing into a cylindrical shape having an open end at one end and a bottom wall at the other end at least partially at the inner periphery. , the first cylindrical body 11a and the second
The cylindrical bodies 11b are joined by a joining part 20 with their open end surfaces abutted against each other, and a case 13 integrally formed using a non-magnetic material is fitted into the yoke 11. Reference numeral 13 indicates a plurality of partition walls 3 on one end surface of the ring 33.
5 are arranged upright in the axial direction at intervals in the circumferential direction, and the height of each partition wall part 35 is formed to be lower than the height of the magnet 12. Each of the magnets 12 is inserted between the cases 13 and 12. Furthermore, a cover 1 made of a magnetic metal material and formed into a cylindrical shape with a flange is inserted into the case 13.
4 is fitted so as to cover the group of magnets 12, and a retaining ring 15 formed in a ring shape using a non-magnetic material is placed on the flange of the cover 14.
is applied, and the bottom wall of the second cylindrical portion 11b presses the case 13 and the group of magnets 12 toward the bottom wall of the first cylindrical portion 11a via the retaining ring 15 and the flange of the cover 14. A rotor of a magnet generator characterized by: