JPH0140309Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a rotor for a magnet generator.

Generally, in small vehicles such as motorcycles, a magnet generator as shown in FIG. 1 is sometimes used. This generator is a magnet unit constructed by arranging and fixing a plurality of ferrite magnets (hereinafter referred to as magnets) 3 in the circumferential direction with equal phase difference on the inner peripheral surface of a cylindrical yoke 2. and a generator 4 consisting of a coil unit configured by winding coils 6 at a plurality of radial locations on the outer periphery of a core 5 made of laminated thin iron plates. When the child 1 is driven by the engine and rotates around the generator 4, an electromotive force is induced in each magnetic pole coil 6 of the generator 4.

In the conventional rotor of such a magnet generator, in order to prevent fragments from being scattered due to rotation in the event that a fragile magnet is damaged, the rotor is attached to a yoke as shown in Fig. 2 or Fig. 3, for example. The magnet fixing structure surrounds the entire circumference of the magnet.

In the structure shown in FIG. 2, the magnets 3A are fitted one by one into the protective frame 7, and the pole pieces 8 are brought into contact with the inner peripheral surfaces of the magnets 3A and 3A.
With the outer circumferential surface of the magnet in contact with the inner circumferential surface of the yoke 2, screws 9 are inserted from the outer circumference of the yoke 2 and screwed into the pole piece 8, and the magnets are tightened and fixed to the yoke one by one. .

However, in such a fixed structure, after fitting the magnets one by one into the protective frame,
Since each piece is tightened and fixed one by one, the number of parts is large, man-hours are required, it is difficult to automate assembly work, and productivity is low.

In the structure shown in FIG. 3, a magnet 3B having a size equal to or larger than two magnets is fitted into a case 10 formed by integrating a protective frame 7A and two pole pieces 8A, 8A into a box shape. After tightening and fixing 10 to the yoke 2 with screws 9, two field poles 3C and 3C are magnetically attached to the magnet 3B, and the task of tightening and fixing two or more pieces can be accomplished at once. By doing so, the decrease in productivity is suppressed.

However, such a fixing structure has the drawback that a neutral portion (magnetic neutral portion) 3D must be interposed in the expensive ferrite, resulting in a wasteful portion and being uneconomical.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotor for a magnet generator that solves the drawbacks of the prior art and can improve assembly workability without requiring the interposition of a neutral part within the magnet. .

In order to achieve this object, the present invention involves fitting a magnet together with a pole piece into each housing chamber of an annularly arranged upper open frame, and further, after abutting a retaining ring on the upper surface of the upper open frame, the yoke is The opening edge of the magnet is placed inward, and the magnet is clamped and fixed between the holding ring and the floor wall of the storage chamber.

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

4, 5, and 6 are exploded perspective views showing an embodiment of the rotor of the magnet generator according to the present invention;
FIG. 2 is a vertical cross-sectional view and an enlarged partial cross-sectional view.

In this embodiment, the rotor as a magnetic unit includes a yoke 11 and a plurality of magnets 12.
, the same number of pole pieces 13, and the case 14,
A presser ring 15 is provided. The yoke 11 is integrally molded with a magnetic material into a cylindrical shape with an open upper surface and a closed lower surface, and the lower closed wall has a shaft hole in the center for inserting a shaft for supporting the generator (see Figure 1). 16, a plurality of mounting holes 17 for directly connecting the rotor to an engine (not shown) at a position outside the shaft hole, and a plurality of rotation stops for stopping the case 14 from rotating at a position outside the mounting hole. Holes 18 are respectively formed and arranged at arbitrary angles with respect to the mounting holes 18. The upper end of the yoke 11 has a winding allowance 1.
9 is formed by cutting the outer periphery.

The magnet 12 has a height H that is 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 direction of the width W. At both ends of the arc-shaped inward surface (hereinafter referred to as the ventral surface) 20 of the magnet 12, inclined portions 22 are arranged such that as they go outward, they approach the arc-shaped outer circumferential surface (hereinafter referred to as the back surface) 21. each formed. Both rising sides 23
and 23, the upper surface 24 and the lower surface 25 are each formed parallel to each other.

The pole piece 13 is press-formed from a metal plate into a substantially rectangular plate having an arc length of 15 to 20 mm and a thickness of approximately 0.5 to 1.0 mm. The height h of the pole piece 13 is set to be less than or equal to the height of the magnet 12, and its width is set to be approximately equal to the width W of the magnet, forming an arc shape curved along the ventral surface 20 of the magnet 12 in the width direction. However, the dimensions of the case are such that there is a press-fit allowance after assembly. Bent portions 26 are formed at both ends of the pole piece 13 in the width direction so as to extend outward toward the back.
Further, the folding portion 26 is tapered such that the folding line approaches the center as it goes downward in the vertical direction. Due to this taper, there is no press-fitting allowance with the case at the initial stage of assembly. Furthermore, a notch 2 is provided at the lower end of the bent portion 26.
7 are formed respectively.

The case 14 is integrally molded from a non-magnetic material such as synthetic resin into a substantially cylindrical shape that fits inside the yoke 11 as a whole. A plurality of storage chambers 31 are formed in the cylindrical wall 30 of the case 14 and arranged in the circumferential direction with substantially equal phase differences. The height of the storage chamber 31 is less than the height H of the magnet 12.
h' and a width slightly larger than the width W of the magnet, and the central portions of the ceiling wall, rear wall, and ventral wall are open. Therefore, the case 14 has a shape in which a plurality of frames each having an open top are connected in a ring shape.
The floor wall portion 32 of each storage chamber 31, that is, the horizontal portion of each open upper frame is arranged next to each other in a series of rings 3.
3, and an appropriate number of protrusions 34 that fit into the locking holes 18 of the yoke 11 are arranged on the lower surface of the ring 33 so as to be located directly below the center of the storage chamber 31. The protrusion 34 is formed in a tapered shape so that the tip thereof is inserted into the locking hole 18 of the yoke 11, and the protrusion 34 is press-fitted from the vicinity of the center to the base. Further, as shown in FIG. 7, an annular groove 34a is recessed in the lower surface of the ring 33 at the base of each protrusion 34 so as to form a space capable of accommodating chips, which will be described later.

Between the adjacent storage chambers 31, 31, there are partition walls 3 corresponding to the vertical pieces of the upper open frame.
5 is formed to stand up like a column. Claw portions 36 are provided at both ends of the ventral surface of the partition wall portion 35 to accommodate the storage chamber 31.
The presser claws 36 are each protruded so as to close a part of the open ventral surface, and each of the presser claws 36 has a substantially triangular cross section, with the surface in contact with the accommodation chamber 31 facing toward the open side (in the direction of protrusion). As it goes forward, it forms a hypotenuse that approaches the ventral surface. Moreover, the presser pawl portion 36 is formed in a tapered shape in which the thickness gradually increases in the back direction as it goes downward in the vertical direction, so that, as shown in detail in FIG. A pair of presser claws 36, 36 of 35
The edges of the cylinder are inclined toward the cylinder core so that they approach each other as they go downward.

Further, a long groove 37 is formed on the ventral surface of the partition wall 35 so as to be substantially parallel to the cylindrical center and to become shallower as it goes downward. It is opened. A long guide groove 38 is formed on the outer circumferential surface of the partition wall 35 and is substantially parallel to the cylindrical center, and the upper end of this groove 38 is also opened at the upper surface of the partition wall.

Furthermore, presser ribs 39 are protruded from both circumferential side surfaces of the partition wall portion 35 in the shape of an elongated triangular pyramid that becomes thinner toward the top.

The retaining ring 15 is integrally formed of the same material as the case 14 and has a circular annular shape that is approximately the same as the cylindrical shape of the case 14. A plurality of ribs 41 that fit into the long grooves 37 of the case 14 are arranged and projected in the circumferential direction so as to correspond to each long groove 37, respectively, on the lower surface of the ring 15. The rib 41 has a thickness t that is slightly smaller than the width T of the long groove 37.
(See FIG. 6) is formed into a substantially rectangular flat plate. The outer edge of the rib 41 is tapered toward the center as it goes downward.

Guide rods 42 that fit into the guide long grooves 38 of the case 14 are protruded from an appropriate number of outer positions of the plurality of ribs 41 so as to correspond to each of the long grooves 38, respectively.

Further, a step portion 43 is cut into an annular shape at the upper end of the outer periphery of the presser ring 15 to improve fitting with the winding allowance portion 19 of the yoke 11.

Next, the assembly work will be explained.

The case 14 is fitted into the yoke 11, and the yoke 1
Each protrusion 34 on the lower surface of the case 14 is fitted into each locking hole 18 on the bottom wall. As a result, the case 14 is attached to the yoke 11 so as to rotate together with the yoke 11.

When the protrusion 34 is inserted into the detent hole 18, the outer peripheral surface of the protrusion is cut by the edge of the detent hole, and the chips may be caught between the bottom surface of the yoke and the bottom surface of the case 14. . If chips get caught between the joint surfaces, not only will the joint surfaces not come into close contact, but the winding allowance between the yoke and the case (see below) will fluctuate, so there is a risk that the case will not be properly fixed to the yoke. Occur.

However, in the protrusion according to the above structure, the chips escape so as to be taken into the annular groove 34a formed at the base thereof, so that the chips may be caught between the bottom surface of the yoke 11 and the lower surface of the case 14. There isn't. Therefore, the bonding surfaces of the two 11, 11 are reliably brought into close contact, the winding allowance does not change, and the attachment accuracy is improved, so that the case is strongly attached and fixed to the yoke.

Subsequently, the magnet 12 and the pole piece 13 are inserted into each housing chamber 31 of the case 14 from above. At this time, the magnet 12 and the pole piece 13 may be inserted either first or both together, but it is necessary to arrange them so that the back surface of the pole piece 13 comes into contact with the vent surface 20 of the magnet 12. As the magnet 12 and pole piece 13 are inserted, the holding claws 36 of the case 14 are tapered so as to sandwich the housing chamber 31 downward, so they are not press-fitted at the initial stage of insertion. ,
As the insertion progresses, at a certain point the magnet and pole piece 13 and the accommodation chamber 31 become press-fitted,
The magnet and pole piece will stop at an intermediate height unless a pushing force is applied.

Next, the guide rod 42 is inserted into the guide long groove 38, and using this as a guide, the ribs 41 are aligned and fitted into the long grooves 37, respectively, and the ribs are pushed into the long grooves by applying a pressing force as evenly as possible as a whole. , the presser ring 15 is brought into close contact with the case 14. With this pushing, the magnet 12 and the pole piece 13, which have stopped at an intermediate height, are press-fitted into each accommodation chamber 31, respectively.

Due to the press-fit relationship between the pole piece 13 and the storage chamber 31, a force F ₁ pushing in the circumferential direction and a force F ₂ pushing towards the center act on the partition wall 35 of the case 11, as shown in FIG. .

Here, if the partition wall portion 35 is formed solid, a strong reaction force against the circumferential pressing force F ₁ is directly applied from the partition wall portion 35 to the pole piece 13.
Together with the central direction pushing force F ₂ , the pole piece 13 is strongly compressed and the arc portion is pushed into the storage chamber 31 .
The rotor deforms toward the center of the yoke so as to protrude from the yoke, causing a problem in which the inner diameter of the rotor becomes smaller.

However, since the partition wall portion 35 according to the above structure has a hollow structure in which the long groove 37 is formed, such a problem does not occur. In other words, since the circumferential pressing force F ₁ acts almost perpendicularly to the long groove 37 of the partition wall 35, the partition wall 35 is elastically deformed by the circumferential pressing force F ₁ so that the width of the long groove 37 is reduced, thereby accumulating force. state, and the pole piece 13 is pushed back with a reaction force based on the accumulated force that substantially alleviates the circumferential direction pushing force _F1 . This reaction force causes the pole piece to push the magnet 12 radially outward as shown by arrow _F3 in FIG. Due to this pressing force _F3 , the back surface 21 of the magnet 12 is strongly pressed against the inner peripheral surface of the yoke and fixed.

Further, due to the center direction pushing force F ₂ , a force is applied to the partition wall portion 35 of the case to push it down inward, but the rib 41 of the presser ring 15 is fitted into the long groove 37 of the partition wall portion 35 . and this rib 41
As shown in FIG. 6, since the partition wall portion 35 is supported by a force F ₄ that resists the pushing force, the partition wall portion maintains an upright state. Since the partition remains in an upright state, the pole piece 13 is pressed into the partition by the presser claw 3 of the partition.
Bent parts 26, 26 at both ends according to the taper of 6
In this step, the circumferential pressing force F ₁ is increased, and the pressing force F ₃ against the magnet 12 is relatively increased.
Due to this pressing force, the magnet 12 is attached to the yoke 11.
It is more firmly pressed and fixed to the inner circumferential surface of the

Note that the rib 41 of the presser ring 15 is connected to the partition wall portion 35.
It is necessary to configure the structure so that a force that causes the long groove 37 to expand does not act on the partition wall portion 35 by simply pushing it back outward when it tends to fall inward. This is because when such a long groove expansion force acts, the arcuate portion of the pole piece 13 bulges toward the center, causing a problem in which the inner diameter of the rotor becomes smaller, just as the partition wall 35 is formed solid. This is because it will happen.

Since the ribs 41 of the retaining ring 15 are formed in a tapered shape that becomes thinner toward the bottom, the partition wall portion 3
Even if 5 is slightly pushed inward, it can be easily inserted into the long groove 37, and the required push-back force F ₄
is obtained. In addition, the bent portion 2 of the pole piece 13
6 is tapered in the vertical direction, it is more reliably prevented that the arc portion of the pole piece 13 deforms toward the center of the yoke and the inner diameter of the rotor becomes smaller when the pole piece 13 is in a power storage state. be done.

As the magnet 12 is press-fitted, the presser rib 39 protruding into the storage chamber 31 at the lower side of the partition wall 35 is crushed by the side surface of the magnet 12. In this crushed state, the rib 39 is compressed and deformed to the magnet 12 and is strongly pressed against it.
In comparison, the positioning of the magnet 12 in the circumferential direction and the vertical direction within the housing chamber 31 is ensured by the ribs 39 on both sides.

Thereafter, the margin portion 19 at the upper end of the yoke 11 is wound and pushed inward, and the yoke 11, case 14, and presser ring 15 are fitted and integrated.

Here, since the height h' of the partition wall portion 35 of the case 14 and the height h of the pole piece 13 are set lower than the height H of the magnet 12, the magnet 12 has its upper surface 24, The lower surface 25 is brought into close contact with the lower surface of the retaining ring 15 and the upper surface of the case floor wall 32 in the storage chamber 31, and is restrained and pressed against the relevant winding portion and the bottom of the yoke 11 via the retaining ring and the case. In other words, the magnet 12 is clamped in surface contact with the retaining ring 15 and the case floor wall 32 over a wide area of the entire upper and lower surfaces, so that it is prevented from floating within the case housing chamber 31 (so-called dancing phenomenon). .

Furthermore, if the rotation stop protrusion 34 is formed directly below the center of the case storage chamber 31, the protrusion will receive a pressing load due to the press-fitting and winding of the magnet 12, etc., so that it will not fit into the rotation hole 18 of the yoke 11. This makes the connection between the yoke and the case 14 even more reliable.

According to this embodiment, the magnet and the pole piece are inserted into each of the storage chambers formed in the case, and the retaining ring is press-fitted into them, so that the number of parts and the number of assembly steps can be reduced. At the same time, screwing or riveting work can be eliminated, improving work efficiency. Also, since each magnet is independent, there are no unnecessary parts such as neutral parts, making it economical. It is advantageous.

Furthermore, the structure is such that the magnet is pressed and fixed to the yoke with an elastic biasing force by the partition wall of the case that is relatively elastically deformed due to the press-fit relationship between the case and the retaining ring, the magnet, and the pole piece. The magnet can be reliably fixed to the yoke for a long period of time under elastic tension.

In addition, in the fixed state, the magnet is surrounded all around by the case, retainer ring, and pole piece, so even if the magnet were to break, the pieces would not be scattered, and the pieces would not be scattered as the rotor rotates. It is possible to prevent the occurrence of secondary troubles due to scattering.

As explained above, according to the present invention, after inserting the magnet and the pole piece into each accommodation chamber of the case, the holding ring is brought into contact with the upper surface of the case, and the mouth edge of the yoke is closed to hold the magnet. Since the magnet is clamped and fixed between the magnet and the bottom of the storage chamber, productivity can be improved and the magnet can be reliably fixed to the yoke for a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an example of a general magnet generator, Fig. 2 is a partial plan sectional view showing a conventional example, Fig. 3 is a partial plan sectional view showing another conventional example, and Figs. 7
The drawings show an embodiment of the present invention; FIG. 4 is an exploded perspective view, FIG. 5 is a vertical sectional view, FIG. 6 is an enlarged partial cross-sectional view, and FIG. 7 is an enlarged partial perspective view. 1... Rotor, 4... Generator, 11... Yoke, 12... Magnet, 13... Pole piece, 14... Case, 15... Holding ring, 18
... Rotating hole, 19 ... Winding margin section, 22 ... Inclined section, 26 ... Bending section, 27 ... Notch section, 30 ...
Cylindrical wall, 31...Accommodation chamber, 34...Protrusion, 34a...
... annular groove, 35 ... partition part, 36 ... presser claw part,
37...Long groove, 38...Long groove for guide, 39...
Presser ring, 41...rib, 42...guide bar.

Claims (1)

[Claims for Utility Model Registration] 1. A plurality of magnet storage chambers 31 are arranged in a ring shape, and adjacent storage chambers 31, 3
The case 14 has long grooves 37 formed on the inner surface of the partition wall 35 between the bowl-shaped yoke 1.
1, and an arc-shaped magnet 12 along the inner circumference of the yoke 11 is fitted into each housing chamber 31 of the case 14, with a pole piece 13 made of a thin plate arranged on the inner surface, Furthermore, each of the ribs 41 protruding from the lower surface of the presser ring 15 on the case 14 is fitted into each of the long grooves 37 of the case 14, and the winding and caulking margin 19 at the upper end of the yoke 11 is wound and caulked. The magnet 12 has sloped portions 22, 22 at both ends of its ventral surface, which are closer to the arc-shaped rear surface 21 as they go outward in the circumferential direction. The pole pieces 13 have bent portions 26 at both ends in the width direction, and the bent portions 26 are tapered so that the folded lines become narrower as they go toward the bottom of the storage chamber 31. Moreover, a gap is formed between the magnet 12 and the inclined part 22 to serve as a press-fitting margin, and the partition wall part 35 has a gap at both ends of the ventral surface of the long groove 37. Presser claws 36, 3 on both sides
6 protrude so as to close a part of the open ventral surface of the storage chamber 31, and the thickness of the presser claws 36 increases as it goes toward the bottom of the storage chamber 31. They are tapered and formed so as to cooperate with the bent portion 26 of the pole piece 13 and press-fit, and furthermore, magnets are formed on both sides of the partition wall portion 35 so as to protrude into the accommodation chamber 31. A presser rib 39 is formed that contacts the side surface 23 of the presser ring 15, and each rib 41 of the presser ring 15 is formed to resist the pushing force of the partition wall 35, and the width of the long groove 37 is equal to the width of the rib. The thickness of the rib 41 is set to be larger than the thickness of the rib 41 so that elastic deformation of the presser claw part 36 occurs when the magnet 41 is inserted, and the height h' of the partition wall part 35 and the height h of the pole piece 13 are The height H of the housing chamber 31 is set lower than the height H of the housing chamber 31, and on the lower surface of the ring 33 of the case 14, each protrusion 34 that fits into the locking hole 18 formed on the bottom surface of the yoke 11 is provided at the center of the storage chamber 31. The pole piece 13 is press-fitted into the storage chamber 31 together with the magnet 12, and the rib 41 of the holding ring 15 is fitted into the long groove 37 of the case 14. By preventing the partition wall portion 35 from falling inward, the presser claw portion 36
is elastically deformed, and the bending portion 26 of the pole piece 13 is pushed by the presser claw portion 36 and elastically deformed, and this elastic force presses and fixes the magnet 12 against the inner peripheral surface of the yoke 11. , the magnet 12 is pressed between the crimped portion 19 of the yoke 11 and the bottom wall via the holding ring 15 and the case 14, and each of the protrusions 34 is fitted into the detent hole 18 so that the case 14 A rotor for a magnet generator, characterized in that the rotor is prevented from rotating by a yoke 11. 2. A rotor for a magnet generator according to claim 1, wherein the protrusion 34 is formed larger than the rotation hole 18. 3. A rotor for a magnet generator according to claim 1, wherein the protrusion 34 has an annular groove 34a recessed at its base.