JP3489553B2 - Thin 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 thin transformer for a switching power supply, which is mounted on a thin power supply used for consumer or industrial electronic equipment.

[0002]

2. Description of the Related Art An example 1 of a conventional thin transformer is shown in FIGS.
This will be described using 1.

An example 2 of a conventional thin transformer is shown in FIGS.
This will be described using 5.

Example 3 of a conventional thin transformer will be described with reference to FIG.

8 to 11, 51 is a primary main winding, 55 and 56 are divided secondary main windings, 57 is insulating paper, 58 is a terminal, 59 is a connecting portion, 60 is a coil base,
Reference numeral 61 indicates a magnetic core.

A spiral coil in which the first layer and the second layer are continuously wound in two layers without cutting in the middle
The next main winding 51 is prepared in advance.

Coil base 60 formed by implanting terminals 58
The secondary main winding 55, the primary main winding 51, and the secondary main winding 56 are laminated in this order on top of the insulating paper 57. Then, the terminal 58 and each winding are connected to each other by a method such as soldering.
Connect the parts to complete the laminated coil. Next, bending and cutting operations are performed so that the secondary main windings 55 and 56 have required dimensions. Next, from the top and bottom of this laminated coil,
Is incorporated to complete a thin transformer as shown in FIG.

12 to 15, 52 and 53 are divided primary main windings, 55 and 56 are divided secondary main windings, 57 is insulating paper, 58 is terminals, 59 is a connecting portion, Reference numeral 60 represents a coil base, and 61 represents a magnetic core.

A spiral coil wound in one layer is prepared in advance as divided primary main windings 52, 53. On the coil base 60 formed by implanting the terminals 58,
Secondary main winding 55, primary main winding 5 through insulating paper 57
The secondary main winding 56, the secondary main winding 56, and the primary main winding 53 are stacked in this order.
After that, the terminal 58 and each winding are connected at the connecting portion 59 by a method such as soldering to complete the laminated coil. Next, in order to make the secondary main windings 55, 56 have the required dimensions,
Perform bending and cutting work. Next, the magnetic core 61 is assembled from above and below the laminated coil to complete a thin transformer as shown in FIG.

In FIG. 16, 62 is a molded coil in which the entire laminated coil is sealed with an insulating resin, 55 and 56 are divided secondary main windings, and 61 is a magnetic core.

After sealing the whole laminated coil with insulating resin,
Bending and cutting operations are performed so that the secondary main windings 55 and 56 have the required dimensions. Next, the magnetic core 61 is incorporated from above and below the laminated coil to complete a thin transformer as shown in FIG.

[0012]

However, in the configuration of FIGS. 8 to 11 showing the conventional example 1, the secondary main windings divided above and below the primary main winding 51 wound in two layers. Since the wires 55 and 56 are arranged in layers and the primary main winding 51 and the secondary main windings 55 and 56 are not completely alternated, the coupling between the windings is deteriorated and the leakage inductance is reduced. Therefore, there is a problem that the loss due to the leakage inductance increases. In addition, when the bending and cutting operations are performed so that the secondary main windings 55 and 56 have the required dimensions, the coil base 6
Since the 0 and the secondary main windings 55 and 56 are not sufficiently fixed, there is a problem that the dimensions after bending and cutting work are likely to vary.

Further, in the structure of FIGS. 12 to 15 showing the conventional example 2, the divided primary main windings 52 and 53 wound in one layer winding, and the divided secondary main windings 55 and 55, 56 are respectively stacked and arranged, and the primary main windings 52, 53 and 2
Although the secondary main windings 55 and 56 are completely alternately laminated, the lead wire is folded back from the inside of the primary main windings 52 and 53, so that a gap is created between the windings and the coupling between the windings is made. And the leakage inductance increases, and the loss due to this leakage inductance increases. Furthermore, since the lead wire is folded back from the inside of the primary main winding,
This step has a problem that the height of the transformer is increased. Further, in the production process, there is a problem that work efficiency is deteriorated in the stacking and assembling process due to rattling due to the step of the lead wire of the primary main winding.

In addition, in the structure of FIG. 16 showing the conventional example 3, in order to easily perform the bending and cutting steps of the secondary main windings 55 and 56, the entire laminated coil is sealed with an insulating resin and laminated. Since the molded coil 62 in which the coil and the secondary main windings 55 and 56 are sufficiently fixed is used, there is a problem that a large amount of investment such as a molding die and molding equipment is required in the production process. It was

The present invention is intended to solve the above-mentioned problems, and has a low leakage inductance and a low transformer height.
The purpose of the present invention is to provide a thin transformer that has good work efficiency in the production process and is inexpensive.

[0016]

In order to solve the above-mentioned problems, the thin transformer of the present invention uses a laminated coil divided into a plurality of primary coil or secondary coil.
A two-layer winding in which the first and second layers are continuously wound into a two-layer winding without cutting in the middle, and the first layer and the second layer are moved on the side opposite to the lead wire of the coil. A primary or secondary main winding formed of a thin plate-shaped conductor having an opening between the first and second layers of the spiral coil, the opening facing the lead wire of the two-layer spiral coil. Sandwich either of them to form a laminated coil, and 2
The transition from the first layer to the second layer of the layer-wound spiral coil is performed by an opening provided in a thin plate-shaped conductor, and a magnetic core is incorporated from above and below the laminated coil.

With the above structure, a thin plate-shaped coil is formed between the first and second layers of the two-layer spiral coil in which the first and second layers are continuously wound into two layers without cutting in the middle. The primary main winding and the secondary main winding can be completely alternated by being formed by sandwiching the conductor of No. 1, and a gap and a step between windings due to folding of the lead wire can be eliminated. it can.

Further, the laminated coil is laminated on the coil base, and the cover is used to sandwich and fix the laminated coil and the thin plate-shaped conductor to obtain sufficient fixing strength between the coil base and the thin plate-shaped conductor. Because you can
The bending and cutting steps of the terminal portion can be easily performed. As a result, it is not necessary to seal the laminated coil with the insulating resin, so that expensive investment such as a molding die and molding equipment can be reduced in the production process.

As a result, the leakage inductance is small,
The height of the transformer can be made low, and it is possible to provide an inexpensive thin transformer with good work efficiency in the production process.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION According to the first aspect of the present invention, in a laminated coil divided into a plurality of layers, either the primary or secondary main winding is provided in the first and second layers. The first layer of the two-layer spiral coil in which the coil is continuously wound in a two-layer winding without cutting in the middle, and the first layer moves to the second layer on the side opposite to the lead wire of the coil. And 2
A laminated coil is formed by sandwiching either a primary or secondary main winding formed of a thin plate-shaped conductor having an opening on the side facing the lead wire of the two-layer spiral coil between the layers. The formation and transition of the two-layer spiral coil from the first layer to the second layer is performed at the opening provided in the thin plate conductor, and further from above and below the laminated coil,
It is formed by incorporating a magnetic core and has a primary main winding and 2
The next main winding can be completely laminated alternately, and gaps and steps between windings due to folding of the lead wire can be eliminated, which reduces leakage inductance and height of the transformer. Work efficiency can be improved even in the production process.

According to a second aspect of the present invention, in addition to the structure of the first aspect, the whole laminated coil is sealed and fixed with an insulating resin, and parts such as a coil base and a cover are unnecessary. As a result, the number of parts can be reduced.

According to a third aspect of the present invention, in addition to the structure of the first aspect, the laminated coil is laminated on the coil base, and the laminated coil and the thin plate-shaped conductor are sandwiched and fixed by using a cover. Since the coil base and the thin plate-shaped conductor have sufficient fixing strength, the terminal portion can be easily bent and cut. As a result, it is not necessary to seal the laminated coil with the insulating resin, so that expensive investment such as a molding die and molding equipment can be reduced in the production process.

According to a fourth aspect of the present invention, in addition to the structure according to any one of the first to third aspects, at least either one of the primary and secondary main windings is provided. Since it is an electric wire with an insulating film and the number of turns can be easily changed, the degree of freedom in design is expanded.

According to a fifth aspect of the present invention, in addition to the structure of the fourth aspect, the electric wire is a rectangular electric wire,
Since the occupancy of the winding can be increased, the winding resistance can be reduced, that is, the loss can be reduced.

According to a sixth aspect of the present invention, in addition to the structure of the fourth aspect, the electric wire is a round electric wire, and the cost of winding material can be reduced. Further, since the winding process can be speeded up, workability is improved.

According to a seventh aspect of the present invention, in addition to the configuration of the fourth aspect, the electric wire is an electric wire with a three-layer insulation film, and sufficient insulation can be guaranteed for a high voltage input. . Also, it is easy to comply with safety standards.

According to the invention described in claim 8 of the present invention, in addition to the structure according to any one of claims 4 to 7, an electric wire is provided with a fusion layer, and the wire is wound as it is. Since it can be fixed spirally in this state, it is possible to speed up the lamination process.

According to a ninth aspect of the present invention, in addition to the structure of the eighth aspect, the fusion layer is of an alcohol fusion type, and the winding can be easily performed only by applying alcohol. Since it can be fixed, equipment can be easily installed.

According to a tenth aspect of the present invention, in addition to the structure of the first aspect, the primary or secondary main winding formed of a thin plate conductor is formed of a non-winding type substrate coil. Since it can be formed in the same layer even when the number of windings is two or more, the laminated coil can be formed without increasing the laminated thickness of the coil.

According to the invention of claim 11 of the present invention, in addition to the structure of claim 10, a non-winding type substrate coil is provided.
It is formed by one thin plate conductor, and the thin plate conductor is provided with a groove and connected outside the transformer, and the number of turns is two or more. Compared with a non-winding type substrate coil, Since the distance between the primary and secondary windings can be minimized, the coupling between the windings can be increased.

According to a twelfth aspect of the present invention, in addition to the structure of the tenth aspect, a non-winding type substrate coil is formed of a printed board by an etching method. Since it is highly versatile, it is possible to improve procurement and reduce costs.

According to a thirteenth aspect of the present invention, in addition to the configuration of the third aspect, a protrusion is provided on at least one of the coil base and the cover where the thin plate conductor is sandwiched and fixed. By forming the height of the protrusions according to the height of sandwiching the thin plate-shaped conductor in the laminated coil, the coil base and the thin plate-shaped conductor can be formed without stressing the laminated coil. Can be fixed, and the reliability of the thin transformer can be improved.

According to a fourteenth aspect of the present invention, in addition to the structure of the thirteenth aspect, the protrusion is formed by two or more steps, and a plurality of thin plate conductors are formed in the laminated coil. When sandwiched, stress is applied to the laminated coil by setting the height and position of the protrusions according to the height of each thin-plate conductor in the laminated coil and the position where the thin-plate conductor is pulled out. The coil base and the thin plate-shaped conductor can be fixed to each other without increasing the reliability of the thin transformer.

According to a fifteenth aspect of the present invention, in addition to the structure of the third aspect, a claw is provided on at least one of the coil base and the cover to fit the coil base and the cover. The coil base, the laminated coil, and the thin plate-shaped conductor can be easily fixed.

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

(Embodiment 1) A first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view of a finished product of a thin transformer, FIG. 2 is an exploded perspective view, and FIG. 3 is a perspective view of essential parts showing a spiral coil portion and a thin plate conductor portion wound in two layers. FIG. 4 is a cross-sectional view of a main part showing a spiral coil portion and a thin plate conductor portion that are wound in two layers.

According to the figure, the first layer and the second layer are continuously wound in a two-layer winding without cutting in the middle, and on the side opposite to the lead wire of the coil, the first layer to the second layer. The two-layer spiral coil moved to the eye
Prepare in advance.

At this time, the first layer is wound from the outside to the inside, and the second layer is wound from the inside to the outside.

Then, on the coil base 10 in which the terminals 8 are planted, the secondary main winding 5 formed of a thin plate-shaped conductor via the insulating paper 7 and one layer of the above-mentioned primary main winding 1 A secondary main winding 6 formed of a thin plate-shaped conductor having an opening 16 on the side opposite to the lead wire of the primary main winding is sandwiched between the second and second layers and laminated in order. At this time, the transition from the first layer to the second layer of the two-layer spiral coil is performed in the opening 16 provided in the thin plate conductor.

After that, the terminal 8 and each winding are connected at the connection portion 9 by a method such as soldering to complete the laminated coil. Next, bending and cutting operations are performed so that the secondary main windings 5 and 6 have the required dimensions. Next, the magnetic core 12 is incorporated from above and below the laminated coil to complete a thin transformer as shown in FIG.

As described above, according to the configuration of FIGS. 1 to 4 showing the first embodiment of the present invention, a thin plate-like shape is provided on the coil base 10 in which the terminals 8 are planted, with the insulating paper 7 interposed therebetween. Secondary winding 5 formed of the conductor of the first main winding 1 has a thin plate-like shape having an opening between the first and second layers of the primary main winding 1 on the side facing the lead wire of the primary main winding. The secondary main winding 6 formed of a conductor is sandwiched in this order, and the primary main winding and
The next main winding can be completely laminated alternately, and gaps and steps between windings due to folding of the lead wire can be eliminated, which reduces leakage inductance and height of the transformer. Work efficiency can be improved even in the production process. In addition, it is possible to reduce expensive investment such as molding dies and molding equipment.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view of a finished thin transformer, and FIG. 5 is an exploded perspective view.

The basic configuration is the same as that of FIGS. 1 to 4 showing the first embodiment of the present invention. The big difference is 1
Opening 16 on the side opposite to the lead wire of the next main winding
The secondary main winding 6 formed of a thin plate-shaped conductor having a thin plate-shaped conductor is formed by one thin plate-shaped conductor, and the thin plate-shaped conductor is provided with a groove 4 to be connected to the outside of the transformer. This is the number of times.

As described above, according to the configuration of FIGS. 1 and 5 showing the second embodiment of the present invention, a thin plate conductor having an opening on the side opposite to the lead wire of the primary main winding is used. The formed secondary main winding 6 is formed by one thin plate-shaped conductor, and the thin plate-shaped conductor is provided with the groove 4 to be connected outside the transformer.
By setting the number of turns to more than one, the distance between the primary and secondary windings can be minimized as compared with the conventional one formed by a non-winding type substrate coil when the number of turns is two or more. It is possible to increase the coupling between the windings.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS.

FIG. 6 is a perspective view of a finished thin transformer, and FIG. 7 is an exploded perspective view.

The basic structure is the same as that shown in FIGS. 1 to 4 showing the first embodiment of the present invention. The major difference is that the first main winding 1 of the secondary main winding 5 and the primary main winding 1 formed of a thin plate-shaped conductor on the coil base 10 formed by implanting the terminals 8 via the insulating paper 7. And a second main winding 6 formed of a thin plate-shaped conductor having an opening 16 on the side opposite to the lead wire of the primary main winding between the first and second layers, and the coil is formed by sequentially stacking The point is that the laminated coil is fixed by using the cover 13 having the claw 15 that fits with the base 10, and the secondary main windings 5, 6 are sandwiched and fixed by the coil base projecting portion 11 and the cover projecting portion 14. Then terminal 8
And each winding are connected by a method such as soldering at the connecting portion 9 to complete the laminated coil, and then the secondary main winding 5,
Bend and cut to make 6 the required size,
Next, by incorporating the magnetic core 12 from above and below this laminated coil,
The point that a thin transformer as shown in FIG. 6 is completed is the same as that of FIGS. 1 to 4 showing the first embodiment of the present invention.

As described above, according to the configurations of FIGS. 6 and 7 showing the third embodiment of the present invention, after the laminated coil is laminated on the coil base 10, the claw 1 fitted with the coil base 10 is fitted.
The laminated coil is fixed using the cover 13 having the coil 5, and the secondary main windings 5 and 6 are further sandwiched and fixed by the coil base protrusion 11 and the cover protrusion 14. Since the main winding can obtain sufficient fixing strength, the bending and cutting steps of the terminal portion can be easily performed. As a result, it is not necessary to seal the laminated coil with an insulating resin, so that it is possible to reduce expensive investment such as a molding die and molding equipment in the production process.

Further, the secondary main windings 5 and 6 in the laminated coil
The height and position of the coil base protrusion and the cover protrusion are set according to the height of the coil and the position where the secondary main windings 5 and 6 are pulled out. With this, the secondary main winding can be fixed, and the reliability of the thin transformer can be improved.

[0052]

As described above, according to the present invention, the primary main windings and the secondary main windings can be completely alternately laminated, and the gaps and steps between the windings due to the folding of the lead wire lead. Therefore, it is possible to provide a thin transformer that has a low leakage inductance, a low transformer height, high work efficiency in the production process, and a low cost.

[Brief description of drawings]

FIG. 1 is a perspective view of a thin transformer according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the thin transformer according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a main part of a laminated coil part and a thin plate-shaped conductor part wound in two layers in the thin transformer according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part of a laminated coil portion wound in two layers and a thin plate conductor portion of the thin transformer according to the first embodiment of the present invention.

FIG. 5 is an exploded perspective view of a thin transformer according to a second embodiment of the present invention.

FIG. 6 is a perspective view of a thin transformer according to a third embodiment of the present invention.

FIG. 7 is an exploded perspective view of a thin transformer according to a third embodiment of the present invention.

FIG. 8 is a perspective view of a thin transformer according to the conventional form 1.

FIG. 9 is an exploded perspective view of a thin transformer according to the conventional form 1.

FIG. 10 is a perspective view of a main portion of a laminated coil portion wound in two layers and a thin plate-shaped conductor portion of a conventional thin transformer according to the first embodiment.

FIG. 11 is a cross-sectional view of a main part of a laminated coil part wound in two layers and a thin plate-shaped conductor part of a conventional thin transformer according to the first embodiment.

FIG. 12 is a perspective view of a thin transformer according to the conventional form 2.

FIG. 13 is an exploded perspective view of a thin transformer according to the conventional form 2.

FIG. 14 is a perspective view of a main part of a laminated coil part and a thin plate-shaped conductor part wound in one layer of a thin transformer according to a second conventional embodiment.

FIG. 15 is a cross-sectional view of a main part of a laminated coil portion and a thin plate-shaped conductor portion that are wound in one layer in a thin transformer according to a conventional form 2.

FIG. 16 is a perspective view of a thin transformer according to the conventional form 3.

[Explanation of symbols]

1 primary main winding 4 grooves Secondary main winding divided into 5 Secondary main winding divided into 6 7 insulating paper 8 terminals 9 connection 10 coil base 11 Coil base protrusion 12 magnetic core 13 cover 14 Cover protrusion 15 nails 16 openings 51 primary main winding 52 divided primary main winding 53 primary windings divided 55 split primary winding 56 divided secondary main winding 57 insulating paper 58 terminals 59 Connection 60 coil base 61 magnetic core 62 Mold coil

─────────────────────────────────────────────────── --Continued front page (56) Reference JP 2000-208341 (JP, A) JP 9-306756 (JP, A) JP 9-237721 (JP, A) JP 7-235428 (JP, A) JP 8-97055 (JP, A) JP 9-186021 (JP, A) JP 7-142263 (JP, A) JP 7-87506 (JP, A) Open 2000-182850 (JP, A) Utility model registration 3058187 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01F 27/28 H01F 27/30 H01F 30/00

Claims (15)

(57) [Claims] 1. A laminated coil divided into a plurality of layers, wherein either the primary or secondary main winding is continuously wound into a two-layer winding without cutting the first and second layers on the way. A two-layer spiral coil wound between the first layer and the second layer on the side opposite to the lead wire of the coil and between the first and second layers of the coil. A laminated coil is formed by sandwiching either a primary or secondary main winding formed of a thin plate-shaped conductor having an opening on the side opposite to the lead wire of the coil, and a spiral coil having two layers. The transition from the second layer to the second layer is performed by an opening provided in a thin plate conductor, and a thin transformer in which a magnetic core is incorporated from above and below the laminated coil. 2. The thin transformer according to claim 1, wherein the entire laminated coil is sealed with an insulating resin. 3. The thin transformer according to claim 1, wherein the laminated coil and the thin plate-shaped conductor are sandwiched and fixed by a coil base and a cover. 4. An electric wire with an insulating film is used for at least one of the primary and secondary main windings.
The thin transformer according to any one of 3 to 3. 5. The thin transformer according to claim 4, wherein the electric wire is a rectangular electric wire. 6. The thin transformer according to claim 4, wherein the electric wire is a round electric wire. 7. The thin transformer according to claim 4, wherein the electric wire is an electric wire with a three-layer insulating film. 8. The thin transformer according to claim 4, wherein the electric wire has a fusion layer. 9. The thin transformer according to claim 8, wherein the fusion layer is of an alcohol fusion type. 10. A primary or secondary formed of a thin plate conductor.
The thin transformer according to claim 1, wherein the next main winding is formed of a non-winding type substrate coil. 11. A non-winding type substrate coil is formed of one thin plate-shaped conductor, and a groove is formed in the thin plate-shaped conductor so as to be connected outside the transformer, and the number of turns is two or more. Item 10. The thin transformer according to Item 10. 12. The thin transformer according to claim 10, wherein the non-winding type substrate coil is formed of a printed circuit board by an etching method. 13. The thin transformer according to claim 3, wherein at least one of the coil base and the cover has a protrusion formed at a portion where the thin plate conductor is sandwiched and fixed. 14. The thin transformer according to claim 13, wherein the protrusion is formed by two or more steps. 15. The thin transformer according to claim 3, wherein a claw is provided on at least one of the coil base and the cover to be fitted therein.