JP3018978B2 - Manufacturing method of flyback transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a flyback transformer used for electronic equipment and electric equipment.

[0002]

2. Description of the Related Art A conventional assembly for forming a ferrite core gap in a flyback transformer will be described with reference to FIGS.

First, the flyback transformer 1 will be described with reference to FIG. A pair of primary ferrite cores 2 and secondary ferrite cores 3 each having an abutting portion coated with an insulating adhesive are incorporated in a resin bobbin 5 around which a polyurethane-coated copper wire 6 is wound.

The ferrite cores 2 and 3 are held by winding a plurality of layers of the polyester tape 7.

[0005] The adhesive applied to the butted portion of the primary ferrite core 2 and the secondary ferrite core 3 is hardened by tapping at room temperature or by heating under constant conditions to form a core gap 4.

Next, a taping device as a ferrite core holding means at the time of forming the ferrite core gap will be described with reference to FIG.

[0007] An adhesive is applied to the butted portion of the primary side ferrite core 2 and the secondary side ferrite core 3, and the flyback transformer 1 incorporated in the resin bobbin 5 around which the polyurethane-coated copper wire 6 is wound is chucked. 8 and hold the tip 11 of the polyester tape 7 to the side of the ferrite core 12.
, The rotational force of the electric motor 10 is transmitted to the chuck 8 via the holder 9, the flyback transformer 1 is rotated in the rotational direction 13, and a plurality of layers of the polyester tape 7 are wound around the ferrite core side surface 12. By doing
A primary ferrite core 2 and a secondary ferrite core 3 are held.

[0008]

However, the above-mentioned method uses the polyester tape 7 on the side surface 12 of the ferrite core.
Are wound in a plurality of layers, so that a core gap 4 which is an abutting portion of the primary ferrite core 2 and the secondary ferrite core 3 is formed.
Thus, there is a problem that the opposite core end faces are displaced by the tension at the time of winding the polyester tape 7 and the accuracy of the transformer characteristics is reduced. In addition, the outer shape of the ferrite core is increased due to the thickness of the polyester tape 7, which is a factor that hinders the miniaturization of the flyback transformer 1.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to improve the accuracy of transformer characteristics and reduce the size of a transformer.

[0010]

In order to achieve the above object, the present invention provides a flyback transformer for holding a flyback transformer.
By using a holding jig in which plate magnets with anisotropic magnetic force are arranged at intervals on a magnet holder made of non-magnetic material, the butting part of the ferrite core is set horizontally on the plate magnet surface. This is a manufacturing method in which the holding jig is set so that a magnetic force acts on the butted portion in the vertical direction, and the ferrite core is bonded.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The manufacturing method of the present invention uses a holding jig in which a plate magnet having anisotropic magnetic force is disposed on a magnet holder made of a non-magnetic material. The suction force acts between the cores to hold the flyback transformer. Therefore, it is possible to cure the adhesive while keeping the gap dimension of the adhesive applied between the ferrite cores constant.

As a result, the accuracy of the core gap can be improved, and the accuracy of the transformer characteristics can be improved.

In addition, since the primary ferrite core and the secondary ferrite core are adhered and held after the adhesive in the core gap is cured, the tape wound around the ferrite core in a plurality of layers can be eliminated. The size of the back transformer can be reduced.

Further, by setting the gap surface between the ferrite cores of the flyback transformer in the horizontal direction and setting the magnetic force to act on the gap surface in the vertical direction by the holding jig, the self-weight of the flyback transformer becomes vertical. In addition, because the attractive force of the plate magnet also works vertically,
Since the flyback transformer can be held more stably, the accuracy of the transformer characteristics can be further improved.

Hereinafter, a manufacturing method according to an embodiment of the present invention will be described with reference to FIGS.

First, as shown in FIG. 2, a magnetic holding jig includes a magnet holder 20 made of a non-magnetic material such as stainless steel or synthetic resin,
And a plurality of plate magnets 21 having anisotropic magnetic force disposed at intervals above. Depending on the magnitude of the magnetic force, the plate magnets 21 are arranged at intervals so that the magnetic force does not interfere with the adjacent plate magnets, and are arranged so that the magnetic force directions are the same.
Is fixed with an adhesive or the like.

The plate magnet 21 of the magnetic holding jig
1 attracts the primary ferrite core 15 downward by magnetic force and also attracts the secondary ferrite core 16 via the primary ferrite core 15 as shown in FIG. Can be held.

At this time, since only a vertical attractive force is applied to the ferrite cores 15 and 16, the core gap 17
Does not occur in the abutting portion forming.

In this holding state, the insulating adhesive applied to the butted portion of the primary ferrite core 15 and the secondary ferrite core 16 is hardened at room temperature or by heating, so that a stable core gap is obtained. 17 can be provided.

FIG. 3 shows the flyback transformer after completion, 14 is a flyback transformer, 18 is a bobbin made of resin, and 19 is a copper wire coated with polyurethane.

According to the present invention, the core gap accuracy can be improved, and the accuracy of the transformer characteristics can be improved. After the adhesive is cured, the primary ferrite core 15
The secondary ferrite core 16 is adhered and held, so that the tape wound around the outer periphery of the ferrite core by a plurality of layers can be eliminated, and the size can be reduced.

[0022]

As described above, according to the manufacturing method of the present invention, in the assembly for forming the ferrite core gap of the flyback transformer, the holding jig provided with the plate magnet having the anisotropic magnetic force fixed to the magnet holder is provided. By using this, the gap dimension can be held with high precision and curing can be achieved, so that the core gap precision can be improved and the transformer characteristics can be improved.

In addition, according to the present manufacturing method, a tape wound around a plurality of layers around the ferrite core can be eliminated, so that the flyback transformer can be reduced in size.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part process in a method of manufacturing a flyback transformer according to an embodiment of the present invention.

FIG. 2 is a perspective view of a holding jig in one embodiment of the present invention.

FIG. 3 is a perspective view showing the appearance of a flyback transformer manufactured in one embodiment of the present invention.

FIG. 4 is a perspective view showing an appearance of a flyback transformer manufactured by a conventional technique.

FIG. 5 is a perspective view showing a taping device used in a conventional manufacturing method.

[Explanation of symbols]

 14 Flyback transformer 15 Primary ferrite core 16 Secondary ferrite core 17 Core gap 18 Resin bobbin 19 Polyurethane coated copper wire 20 Magnet holder 21 Plate magnet

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masato Moriwaki 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (58) Field surveyed (Int.Cl. ⁷ , DB name) H01F 38/42, 41/02

Claims (1)

(57) [Claims] When a pair of ferrite cores are assembled into a bobbin and a butted portion of the ferrite cores is bonded, a plurality of plate magnets having anisotropic magnetic force are spaced from each other on a magnet holder made of a non-magnetic material. Using the holding jig arranged in place, the ferrite core assembled into the bobbin and coated with adhesive at the butted part is placed on the plate magnet of the holding jig.
A method for manufacturing a flyback transformer in which an abutting portion is attracted and held so as to be horizontal to a plate magnet surface, and an adhesive at the abutting portion is cured.