JPH0336940A - Rotor for magnet generator - Google Patents

Abstract

PURPOSE:To secure a magnet reliably through a simple structure by folding the caulked portion of a yoke toward the inner circumferential side and securing a magnet cover then pressing the top of magnet by means of the magnet cover. CONSTITUTION:A case, a plurality of magnets 12, and a cover 14 are inserted into a yoke 11. A thin caulking portion 19 is formed at the outer circumferential side. Then the caulking portion 19 of the yoke 11 is folded toward the inner circumferential side. Consequently, the tip of the upper flange section 43 of the cover 14 is pressed toward the inner circumference and secured to the yoke 11. Consequently, the upper flange section 43 of the cover 14 functions as a resilient body for pressing the top of the magnet 12, and the magnet 12 is secured to the yoke 11. By such arrangement, the magnet 12 is secured reliably and the work process is shortened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotor for a magnet generator, and particularly relates to an improvement in the fixing structure of permanent magnets, and is suitable for small or special vehicles such as motorcycles and buggies. This article relates to an effective use of the on-board d-stone engine in the rotor of the machine.

[Conventional technology]

In general, small or special vehicles such as motorcycles and buggies use permanent magnets such as ferrite magnets (
A magnet generator using a magnet (hereinafter referred to as a magnet) is sometimes used.

This type of magnet generator consists of a rotor consisting of a plurality of magnets arranged and fixed at equal intervals around the inner periphery of a yoke, and a core with coils wound at multiple radial locations. The rotor is driven by an engine and rotates around the generator, thereby inducing an electromotive force in each magnetic pole coil of the generator.

Conventionally, as a rotor used in such a magnet generator, a case is fitted into a yoke, and the case is formed by connecting a plurality of magnet storage chambers with shapes corresponding to the magnets in a ring shape with an open upper frame. , the magnets are inserted into each storage chamber of this case and clamped and fixed between the partition walls between adjacent storage chambers, and a cylindrical cover is fitted inside the case and the magnet nod. After a resin presser ring is brought into contact with the upper flange of the cover, the crimping margin formed on the outer periphery of the upper end of the yoke is rolled and crimped onto the presser ring, thereby forming a plurality of magnets. There is one in which the yoke is integrated with the yoke.

In this case, a slight IMy# is formed between the magnet and the inner circumferential side of the yoke's winding and caulking part, so a resin ring is attached between the magnet and the winding and caulking part in order to increase this gap. This resin ring prevents the pressing load of the crimped portion from acting concentratedly on a portion of the magnet, and prevents cracking of the magnet by dispersing stress.

[Problem to be solved by the invention]

However, in the rotor of a magnet generator using a resin ring, there is a problem that as the number of parts increases, the number of assembly steps increases. In addition, the resin ring may be pushed out to the inner circumference by the tip of the yoke's crimped part, or the magnet may be pushed out to the inner periphery by the crimped part of the yoke.
There is a problem that the inner diameter of the t. Furthermore, there is also the problem that the axial length of the yoke becomes longer by the thickness of the resin ring.

Therefore, as described in JP-A-61-280747 and JP-A-61-288759,
It has been proposed that the top side of a cover attached to the inner peripheral side of the yoke is bent to support the magnenod. However, in the former case, the opening edge of the flange part of the cover is a free end, which is not sufficient to support the magnet, and in the latter case, the magnet cannot be fixed by elastic force. Not enough to hold the magnet in place.

An object of the present invention is to provide a rotor for a magnet generator in which a magnet can be securely fixed by a simple method.

[Means to solve the problem]

The rotor of the magnet generator according to the present invention is a magnet generator in which a plurality of magnets are arranged at intervals around the inner periphery of a substantially bowl-shaped yoke, and a cylindrical cover is fitted inside the magnets. In the rotor of the machine, an annular winding margin is formed on the outer periphery of the open end of the yoke, and an annular stepped portion that slightly protrudes in the axial direction from the top of the magnet is formed on the inner periphery. , an upper flange is formed on the top of the cover so as to protrude outward in the radial direction from the top of the magnet, and its tip extends to the vicinity of the 11il side within the crimping margin of the yoke, and an upper flange is formed in the middle thereof. A stepped part is formed that is bent from the top side of the magnet to the yoke opening end side, and the staking margin of the yoke is bent toward the inner circumference, and the tip of the upper flange is pressed toward the Fk1 circumference side. The device is characterized in that the space between the tip of the upper flange and the stepped portion is bent by this pressing, and the proximal end of the upper flange is pressed against the top of the magnet.

[Effect]

According to the above-mentioned means, when the staking allowance of the yoke is bent inward, the tip of the upper flange is pressed inward by the inward rotation of the yoke, and this pressing causes the upper flange to be bent inward. The portion between the tip of the section and the stepped section is bent. This bending causes the upper flange to act as an elastic body, and this elastic force presses the base end of the upper flange against the top of the magnet, thereby supporting the magnet. This pushes the magnet out in the circumferential direction, making it possible to securely fix it.

〔Example〕

Fig. 1 is an exploded perspective view showing a rotor of a magnet generator according to an embodiment of the present invention, Fig. 2 is a cross-sectional view showing the main parts of the rotor before winding and crimping, and Fig. 3 after winding and staking. 4 is a longitudinal sectional view showing the assembled state, FIG. 5 is a plan view thereof, and FIG. 6 is a partially omitted plan view showing the assembly in progress.

In this embodiment, the rotor of the magnet generator according to the present invention includes a yoke 11, a plurality of magnets 12, a case 13, and a cover 14.

The yoke 11 is integrally molded with a magnetic material into a substantially bowl-like shape with an open upper surface and a closed lower surface.The lower closed wall has a shaft hole 16 in the center for inserting a boss (not shown) directly connected to the engine. In addition, a plurality of mounting holes 17 are formed at positions outside the shaft hole 16 to connect the rotor to the boss. For mounting, a plurality of protrusions 18 for preventing rotation of the case i3 are provided at positions outside the hole 17 by pushing up the lower closing wall from the outside. are arranged circumferentially at arbitrary angles.

On the open end side of the yoke 11, a winding caulking allowance L9, which is a thin walled portion on the outer periphery side, is formed by removing the inner circumference of the yoke 11.
An annular step 19a slightly protruding from the top of the magnet 12 in the axial direction is formed on the IiI side of the magnet 9.

An annular groove 19b having a semicircular cross section is recessed along the circumferential direction between the step 191 and the inner circumferential surface of the swaging portion 19.

The magnet 12 has a height less than or equal to the depth of the yoke 11,
It is integrally molded into a substantially rectangular parallelepiped having an arcuate shape curved along the inner periphery of the yoke 11 in the width direction. An arc-shaped inner peripheral surface (hereinafter referred to as the ventral surface) 20 of the magnet 12
At both upper and lower ends of the slanted surface portions 22 are formed such that they become farther away from each other as they go to the outer surface C (hereinafter referred to as the back surface) 21. 6 The rising side surfaces 23 and 23 on both sides pass through the center of the partition wall portion to be described later. It is formed to be perpendicular to the tangent to the normal, and the upper surface 24
and the lower surface 25 are formed parallel to each other.

The case 13 is integrally molded using a non-magnetic material having appropriate elasticity, such as resin, and is generally formed into a generally cylindrical shape that fits inside the yoke IT. A plurality of storage chambers 3I are formed in the cylindrical wall 30 of the case 13 and arranged in the circumferential direction with substantially equal phase differences. The accommodation chamber 31 is formed into a hollow chamber having a height equal to or less than the height of the magnenod 12 and a width slightly larger than the width of the magnenod 12, and its ceiling wall and rear wall are located at the center of the ventral wall. are each open to the public. Therefore, the case 13 is formed into a shape in which a plurality of frames each having an open top are connected in an ffi shape.

The floor walls 32 of each storage chamber 31, ie the lateral pieces of each open top frame, 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 corresponds to the projection 1B in the yoke 11.
is formed to fit.

Between the adjacent storage chambers 31, 31, each partition wall portion 35 corresponding to each vertical portion of the upper open frame is formed to stand up in a substantially H-shaped columnar shape, and each partition wall portion 3
The wall thickness of magnet 5 is formed to be slightly thinner than that of magnet 12. 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 (direction perpendicular to the normal line passing through the center of the partition wall in the circumferential direction). The holding portion 36 is formed into a substantially triangular prism shape with a tapered triangular male portion 36a at the upper end.

The cover 14 is integrally formed by drawing press processing using a magnetic metal material such as a thin iron plate, and is formed into a generally cylindrical shape that fits inside the case 13. Before assembly, the cover 14 At the lower end of the cylindrical part 41, a lower flange part 42 has a circular ring shape that projects inward in the radial direction.
At the upper end thereof, an upper collar portion 43 is formed in the shape of a circular ring that projects outward in the radial direction.

A stepped portion 44 is disposed approximately in the center of the upper flange 43 of the cover 14 in the radial direction, and the upper flange 43 itself is bent and formed by press working so that the stepped portion 44 is continuous in the circumferential direction. It is formed in a circular ring shape, and the upper frame flange part 43 has an inner horizontal part 43a and a trauma horizontal part 43b, both of which are 43a, 43.
They are integrally formed in a backward bent shape connected by this stepped portion 44 perpendicular to b. The outer peripheral edge of the outer horizontal portion 43b of the upper collar portion 43 is the crimping margin 1 of the yoke 11.
It is formed so as to extend to the vicinity of the inner peripheral side at 9.

Next, the structure of the rotor of the magnet generator will be explained by explaining the assembly work of the rotor of the magnet generator using each part related to the tI precept.

First, the case 13 is fitted into the yoke 11, and the yoke 1
The concave portions 3 - 4 on the lower surface of the case 13 are respectively fitted into the convex portions 18 raised on the a-wall of the case 1 . 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 magnene 12 is press-fitted into each accommodation chamber 31 of the case 13 from above, and at this time, the case 1
The side surface 2 of the magnetor 1-12 that comes into contact with the holding portion 36 of No. 3
A chamfered portion or a curved surface of about 30° to 50° is formed at both corners of the magnet 12, so that the magnet 12 can be attached to the holding portion 36 without scraping the holding portion 36.
is pushed in as if to crush it. When the magnet) 12 is strongly pushed into the storage chamber 31, as shown in FIG.
6 is strongly pressed against the side surface of the magnet 12 so as to be crushed. In this crushed state, the holding part 36 is deformed by the magnet 12 and is strongly resilient, so the magnet 12 is relatively pressed by the holding parts 36.3G on both sides in the accommodation chamber 31. It will fit. At this time, since the holding part 36 protrudes tangentially to the partition wall part 35 and the side surface of the magnet 12 is formed approximately parallel to the normal line, that is, at a substantially right angle to the pressed part 36, the magnet 12 Holding parts on both sides 36.36
The resultant force FI of the pressing force Fl and F
I causes the magnet 12 to connect its back surface 21 to the yoke 11.
It is mechanically fixed by being strongly pressed against the inner circumferential surface of the

Incidentally, the reaction force of the pressing force F (or F) of the presser part 36 is the same as that of the partition wall part 35 in which the presser als36 is perforated.
The pressing force F (or FI) of the pressing portion 36 on the opposite side is calculated. That is, the magnets 12, the partition wall portions 35, and the presser portions 36, which are alternately arranged in an annular shape, are pressed against each other along the inner circumferential surface of the yoke LL.

Thereafter, magnets 12! The cover 14, which is formed into a cylindrical shape having an outer diameter approximately equal to the diameter of the circular inner circumferential surface constituted by ff, is press-fitted as shown in FIG.

When press-fitting, each collar portion 42.
43, even if the cover 14 is made of a thin iron plate, sufficient rigidity is ensured in the cylindrical portion 41 thereof.

Therefore, the cover 14 is press-fitted into the case 11 smoothly and in such a way that the outer peripheral surface of the cylindrical portion 41 of the cover 14 uniformly and closely contacts the entire inner peripheral surface of the case 14. Further, since a jig for applying a pushing force or a reaction force opposing this to the cover 14 can be engaged with both flanges 42 and 43 during press fitting, the press force is applied to the entire cover 14. The force can be applied uniformly, and precise press-fitting can be achieved. After the lower flange 42 of the cover 14 is press-fitted, it is expanded downward in the axial direction, bent inward in the radial direction, and wound around the lower end of the magnet 12.

After this, when the winding and caulking allowance 19 of the yoke 11 is wound and caulked radially inward, the winding and caulking allowance 19 is radially inward with the vicinity of the annular groove 48 as a fulcrum, as shown in FIG. Since the outer horizontal portion 43b of the upper collar portion 43 is bent inward, its tip is pushed downward in the axial direction by the inner circumferential wall surface of the crimp portion 19, and the outer horizontal portion 43b of the upper collar portion 43 is pressed downward in the axial direction by the inner circumferential wall surface of the crimp portion 45 and the upper surface of the step 19a. When the outer 1'il edge is pushed downward in the axial direction by the 0-turn caulking portion 19 held by the upper (
Since the elastic deformation portion 43C is formed by sliding between the outer peripheral edge of the flange portion 43 and the stepped portion 44, an elastic force M is applied to the upper flange portion 43. This elastic deformation part 4
Due to the elastic force of 3G, the inner horizontal portion 43a located on the base end side of the upper collar portion 43 presses against the top upper surface 24 of the magnetoresistive member 12.

Due to the pressing force of the upper flange 43 of the cover 14, the magnet 7) 12 is pushed downward in the axial direction, and is reliably prevented from being pulled out from the yoke 11.

In this way, according to this embodiment, the magnet 12 can be securely fixed without using a resin ring, so the number of parts and assembly man-hours can be reduced.
Production costs can be reduced. Furthermore, since the resin presser ring can be eliminated, the axial length of the yoke can be shortened by the thickness of the ring.

In addition, since the annular groove 19b is formed on the inner circumferential side of the winding and caulking allowance 19, stress when crimping the winding and caulking allowance 19 is not applied to the magnet 1, and the winding and caulking allowance is The winding and crimping process 19 prevents the magnet 12 from being pushed out in the inner circumferential direction, making it possible to provide a product with stable dimensional accuracy. Further, since the diameter of the crimping margin 19 may be equal to the diameter of the contact portion of the yoke 11 with the magnet 12, the blank diameter of the yoke tt can be reduced, and the material yield can be improved.

Note that the present invention is not limited to the above embodiments,
It goes without saying that various changes can be made without departing from the gist of the invention.

For example, instead of wrapping the lower flange 42 under the magnet 12, the lower flange 42 and the bottom wall of the yoke 11 may be fixed using sponoto welding or a bend.

The positioning of the magnet in the axial direction is not limited to using a case, but may be configured such that a pedestal is formed by cutting the inner circumferential surface of the yoke and the magnet is brought into contact with the pedestal.

(Effects of the Invention) As described above, according to the present invention, the stepped portion is formed on the upper flange of the cover, and the opening 5fiy of the yoke is
By forming a winding crimping allowance on the outer periphery of A, bending the winding crimping allowance towards the inner periphery and pressing the upper flange, and forming an elastic deformation part in the upper flange due to this pressing, this elastic force can be reduced. Since it is configured to prevent the magnet from moving in the axial direction, it is possible to securely fix the magnet and reduce the number of work steps and parts.
Production costs can be reduced.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, in which a magnet is emitted t1! Figure 2 is a sectional view showing the main parts of the rotor before winding and caulking, the third factor is a cross-sectional view of the main parts after winding and caulking, and Figure 4 shows its assembled state. FIG. 6 is a partially omitted plan view showing a state in the middle of assembly. ll...Yoke, 12...Magnet, 13...
Case, 14...Cover, 15...Protrusion, 16...
・Shaft hole, 17... Mounting hole, 18... Convex part, 19
... Winding crimping ((part, 19a... step, 19b...
・Annular groove, 20... ventral surface, 21... dorsal surface, 22...
・Slope part, 23...Side surface, 24...Top surface, 25・
...Bottom surface, 30...Cylinder wall, 31...Containment chamber, 32.
...Bottom wall portion, 33...Ring, 34...Concave portion, 3
5... Partition wall part, 36... Pressing part, 41... Cylindrical shape 42... Lower side flange part, 43... Upper side flange part, 4
4... Stepped plate 45... Winding and caulking part.

Claims (1)

[Claims] 1. In the rotor of a magnet generator, a plurality of magnets are arranged at intervals around the inner circumference of a roughly bowl-shaped yoke, and a cylindrical cover is fitted inside the magnets.
An annular winding margin is formed on the outer periphery of the opening end of the yoke, and an annular stepped portion that slightly protrudes in the axial direction from the top of the magnet is formed on the inner periphery of the yoke. an upper flange is formed to protrude outward in the radial direction from the top of the magnet, and its tip extends to the vicinity of the inner circumferential side of the staking margin of the yoke;
A stepped part is formed in the middle of the magnet, which is bent from the top side of the magnet to the yoke opening end, and the staking margin of the yoke is bent inward, so that the tip of the upper flange is on the inner circumferential side. A rotor for a magnet generator, characterized in that the space between the tip of the upper flange and the stepped portion is bent by this pressing, and the base end of the upper flange is pressed against the top of the magnet.