JP2003163123A - Transformer for power supply - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transformer for power supply which has a big coupling coefficient miniaturizing the entire transformer for power supply. <P>SOLUTION: The transformer is provided with a core intermediate leg 11 having an electrical insulation property, a first winding portion 21a formed in a spiral shape of a first flat and rectangular conductor 21 surface-insulated, and a second winding portion 23a formed in the spiral shape of a second flat and rectangular surface-insulated conductor 23. The first side face of the first winding portion 21a is closely contacted to the peripheral face of the core intermediate leg 11, and the long width direction is wound so that the core intermediate leg 11 is vertical in the axial direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply transformer used for electrical equipment, industry and consumer.

[0002]

2. Description of the Related Art Conventionally, a transformer for a power source used in a discharge lamp lighting device or the like has a helical coil formed by winding a rectangular conductor in advance on an insulating bobbin or a winding jig. The formed coil was removed from the bobbin and inserted into the core.

As a coil having a coil inserted therein, there is a coil component disclosed in Japanese Patent Laid-Open No. 7-335449. In the coil component described in JP-A-7-335449, the cross section T
A coil component having a die core and a C-shaped cross-section, and improving the strength against external force by providing a gap between the T-core and the C-core, and being thin and having a large inductance.

[0004]

However, in this coil component, since a round wire having a circular cross section is wound around the core middle leg to form a coil, a gap is formed between the wound round wires. .

When the rectangular conductor is previously formed into a spiral coil by a bobbin or the like and then inserted into the core middle leg, the inner diameter of the coil and the outer diameter of the core middle leg should be adjusted in order to ensure stable manufacture. A sufficient tolerance is required. Furthermore, since the bobbin itself is thick, there may be a gap between the inner peripheral surface of the coil and the outer peripheral surface of the core middle leg.
A gap also occurs between the coils. Due to this gap, there are problems that the coupling coefficient of the transformer is reduced and it is not possible to reduce the size of the entire transformer.To solve this problem, there is a problem between the coils and between the coil inner peripheral surface and the core middle leg. A transformer with no gap on the outer peripheral surface or a conductor in which the conductors are tightly wound around the core middle leg has not been provided.

Therefore, the present invention has been made in view of the above circumstances, and an object thereof is to provide a transformer having a large coupling coefficient while achieving downsizing of the entire transformer.

Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a transformer having a large transformer coupling coefficient while reducing the size of the entire transformer.

[0008]

To achieve the above object, a power supply transformer of the present invention has the following configuration.

According to the first aspect of the present invention, a cylindrical core middle leg having an electric insulating property and a long first rectangular conductor wire which is surface-insulated and has a rectangular cross section and has a width direction and a thickness direction. The first winding part having a spiral shape and the second winding wire having a surface-insulated second flat conductor wire formed in a spiral shape.
A power supply transformer comprising: a winding part;
The winding portion is wound such that one end surface of the first flat conductor wire is in close contact with the outer peripheral surface of the core middle leg and the longitudinal direction of the first flat conductor wire is perpendicular to the axial direction of the core middle leg. It is characterized by being turned.

According to a second aspect of the present invention, in the power supply transformer according to the first aspect, the flat conductor wire is formed by laminating a plurality of thin conductor wires in the thickness direction.

According to a third aspect of the invention, in the power supply transformer according to the first or second aspect, the first flat conductor wire is a thick flat conductor wire, and the second flat conductor wire has a rectangular cross section. Is a long thin rectangular conductor wire formed in the width direction and the thickness direction, and the second winding portion is
One end surface of the second flat conductor wire is in close contact with the outer peripheral surface of the core middle leg, and the second flat conductor wire is wound such that the longitudinal direction of the second flat conductor wire is perpendicular to the axial direction of the core middle leg. The first winding portion is formed in close contact with both axial end surfaces of the core middle leg of the second winding portion.

According to a fourth aspect of the present invention, in the power supply transformer according to the first or second aspect, the first flat conductor wire is a thin flat conductor wire, and the second winding portion is
A long thin rectangular conductor wire having a rectangular cross section and having a width direction and a thickness direction, wherein one end surface of the second rectangular conductor wire is in close contact with an outer peripheral surface of the first winding portion,
It is characterized in that the second flat conductor wire is wound so that a longitudinal direction thereof is perpendicular to an axial direction of the core middle leg.

According to a fifth aspect of the present invention, in the power transformer according to the third or fourth aspect, the thick flat conductor wire is a primary side and the thin flat conductor wire is a secondary side. And

According to a sixth aspect of the invention, in the power transformer according to any one of the first to fifth aspects, the end wire portion of the first winding portion and the end wire portion of the second winding portion are provided. 6. The power supply transformer according to any one of claims 1 to 5, wherein and are drawn out to the side of the power supply transformer so as to sandwich the core middle leg.

According to a seventh aspect of the invention, in the power transformer according to any one of the first to fifth aspects, the end wire portion of the first winding portion and the end wire portion of the second winding portion are provided. And are drawn out in the same direction to the side of the power supply transformer.

According to an eighth aspect of the invention, in the power transformer according to any one of the first to seventh aspects, the core middle leg, the first winding portion and the second winding portion are the first and second winding portions. It is characterized in that it is resin-sealed in a state where both end portions of the one flat rectangular conductor wire and both end portions of the second flat rectangular conductor wire are led out.

According to a ninth aspect of the present invention, when manufacturing the power transformer according to any one of the first to eighth aspects, a hole having a diameter larger than the diameter of the core middle leg is formed in the longitudinal direction. A manufacturing method of manufacturing using a core winding jig, comprising: an inserting step of inserting the core middle leg into the hole of the winding jig; A winding step of winding the core middle leg so as to be in close contact with the outer peripheral surface of the leg, and a pressing step of pressing the rectangular conductor wire closely contacting the core middle leg in the axial direction of the core middle leg by the winding jig. And, the winding step and the pressing step are sequentially repeated.

According to a tenth aspect of the invention, in the method of manufacturing a power transformer according to the ninth aspect, the winding jig is
A slit is formed in the longitudinal direction thereof, and before the winding step, there is also provided an introducing step of introducing the first rectangular conductor wire into the slit, and the winding step includes the winding jig. It is characterized in that the core middle leg is used as the axis of rotation for rotation.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) A first embodiment of the present invention will be described below with reference to FIG. In the present embodiment, the power transformer includes a core middle leg having electrical insulation, a first winding portion formed of a first rectangular conductor wire spirally wound around the core middle leg, and the core middle leg. And a second winding portion formed of a second flat conductor wire wound in a spiral shape.

FIG. 1 (a) is an external view of a transformer for a power source, FIG. 1 (b) is an external view of an E-shaped core half having a core middle leg, and FIG. 1 (c) is FIG. 1 (a). 1 is a cross section taken along line AA ′ of FIG.
(D) shows equivalent circuit diagrams of the transformers.

As shown in FIG. 1 (b), the E-shaped core half body 10 is made of Ni-Zn type ferrite having a high insulating property, and its shape is E with a core middle leg 11 and a collar portion 12. As shown in FIG. 1A, an end wire portion 22 of the first flat conductor wire 21 and an end wire portion 24 of the second flat conductor wire 23 wound around the outer peripheral surface of the core middle leg 11 are formed. Can be pulled out to the side of the transformer. The E-shaped core half body 10 and the I-shaped core half body 13 are combined to form a closed magnetic circuit type transformer. The end wire portion 22 and the end wire portion 24 are located at both ends of the first rectangular conductor wire 21 and the second rectangular conductor wire, respectively. In FIG. 1A, only one of the end portions of the end line portion 22 and the end line portion 24 is shown, but the end line portion 2 is on the back side of the drawing.
2 and the other of the end line portions 24 are drawn out, respectively.

The first rectangular conductor wire 21 and the second rectangular conductor wire 23
Is made of a conductor such as copper, and its surface is coated with an insulating film. When manufacturing the flat conductor 21, the round copper is compressed and flattened to have a flat cross section, and the flat copper is coated with polyurethane, polyester, enamel or the like.

As shown in FIG. 2 (a), the winding jig 30 has a hole 33 formed in the axial direction to form an air core, and a slit 31 is provided along the axial direction. There is. The width of this slit 31 is the same as that of the first rectangular conductor wire 21 and the second rectangular conductor wire 21.
The width is a little larger than the thickness of the flat conductor wire 23, and the width is such that the flat conductor wire passing through the slit 31 can pass smoothly.

Next, a method of manufacturing this transformer will be described below. As shown in FIG. 2B, the winding jig 30
Is inserted into the core middle leg 11 of the E-shaped half body 10. next,
The end wire portion 22 of the first rectangular conductor 21 is fixed to the flange 12 of the E-shaped core half body 10, and the first rectangular conductor 21 is introduced into the slit 31. One end wire portion 2 of the first rectangular wire 21
2 fixed to the E-shaped core half body 10, the core middle leg 1
The winding jig 30 is rotated about the axis 1. Winding jig 30
When is rotated, the first flat conductor wire 21 introduced into the slit 31 is pulled out. When wound around the core middle leg 11,
Since the first rectangular conductor 21 is pulled out from the direction intersecting the winding direction, tension is applied to the first rectangular conductor,
As a result, the one end surface of the first flat conductor wire is wound so as to be in close contact with the core middle leg 11. By pressing the wound first flat conductor wire 21 toward the flange portion 12 of the E-shaped core half body 10 by one end surface of the winding jig 30, the wide surface of the first flat conductor wire 21 is made into the E-shaped core half body 10. It is in close contact with the collar portion 12 of. further,
By rotating the winding jig 30, the first rectangular conductor 2
1 is pulled out and wound around the core middle leg 11, and the wound first flat conductor wire 21 is pushed toward the flange portion 12 by the winding jig 30. By sequentially repeating this process, the first rectangular conductor wire 21 is directly wound so as to be in close contact with the outer peripheral surface of the core middle leg 11 to form the spiral first winding portion 21a.

The above steps are also performed on the second rectangular conductor wire so that the first winding portion 21a and the second winding portion 23a have the core middle leg 1
1 is formed in close contact with the axial direction of FIG.
The transformer shown in (a) is formed.

As shown in FIG. 1A, the first winding portion 21
The end line portion 22 of a and the end line portion 24 of the second winding portion 23a are drawn out in the same direction of the transformer with the core middle leg 11 interposed therebetween. By bending the drawn end line portion in the axial direction of the core middle leg 11, a shape suitable for mounting the transformer in a direction in which the core middle leg 11 is perpendicular to the substrate (not shown) is provided, and Implementation is also possible. Note that FIG. 1 (a)
Then, the end line portion 22 may be pulled out to the inner side of the drawing while the end line portion 24 is being pulled out.

FIG. 4 shows that the parts other than the end wire portion 22 of the first flat conductor wire 21 and the end wire portion 24 of the second flat conductor wire 23 are resin-sealed. By sealing the transformer with the resin in this manner, the moisture resistance and the insulating property are improved, so that the transformer can be directly mounted on the substrate, and the height and size of the transformer can be reduced.

As an embodiment in which the end line portion 22 and the end line portion 24 are pulled out in different directions, as shown in FIG.
2 and the end line portion 24 may be drawn out to the side of the transformer in the same direction, and in this case, it is suitable to mount the transformer by making the core middle leg 11 horizontal to the substrate (not shown). .

In this manufacturing method, the winding jig 30 is
Although it was rotated with respect to the mold core half body 10, conversely, the winding jig 30 was fixed, and the E-shaped core half body 1 with the core middle leg 11 as an axis.
0 may be rotated, and the material of the E-shaped core half body 10 is
A silicon steel plate, permalloy or the like can be used, but in the case of a conductor, the surface is insulated.

As described above, by directly winding the first rectangular conductor wire 21 and the second rectangular conductor wire 23 around the core middle leg 11, the gap between one side surface of the rectangular conductor wire and the core middle leg is reduced, and As compared with the case where the round wire is wound around the core middle leg, the conductor wires can be wound more closely so that the conductor wires can be wound more densely, so that the coupling performance of the transformer can be reduced and the size can be reduced.

(Second Embodiment) A second embodiment of the transformer according to the present invention will be described below. In the present embodiment, as shown in FIG. 5A, the transformer includes a T-shaped core half body 14 having an electrically insulating core middle leg 11, and
A T-shaped core half is provided with a C-shaped core half body 15 that comes into contact with the tip of the core middle leg 11 at both ends of the collar portion, and a first rectangular conductor 21 wound in a spiral shape on the core middle leg 11. The body 14 and the C-shaped core half body 15 constitute a closed magnetic circuit type transformer.

The first flat conductor wire 21 is formed by compressing a surface-insulated iron wire and flattening it so as to have a rectangular cross section. One side end face of the core middle leg 11 is the same as in the first embodiment. It is wound in close contact with the outer peripheral surface to form a spiral shape. In addition, FIG. 5B is BB ′ of FIG.
FIG. 5C shows a cross section and an equivalent circuit diagram, respectively.

A method of manufacturing this transformer will be described below. As shown in FIG. 6A, a winding jig 34 having a hole 35 having a diameter larger than the diameter of the core middle leg 11 of the T-shaped core half body 14 is inserted into the core middle leg 11. Next, as shown in FIG. 6B, one end wire portion 22 of the first rectangular conductor 21 is fixed to the collar portion 16 of the T-shaped core half body 14. Next, the rectangular conductor 21 is held so that it can be pulled out only in the direction orthogonal to the axial direction of the core middle leg 11, and the winding jig 34 is also fixed so as not to rotate. When the T-shaped core half body 14 is rotated about the core middle leg 11, the first flat conductor wire 21 having the one end wire portion 22 fixed to the T-shaped core half body 14 moves in the axial direction of the core middle leg 11. It is wound in a direction orthogonal to each other, and one end face thereof is in close contact with the core middle leg 11. By pushing the winding jig 34 toward the flange portion 16 of the T-shaped core half 14, the first rectangular conductor 21 wound around the core middle leg 11 is moved to the T-shaped core half 1.
It is brought into close contact with the collar 16 of No. 4. Further, by rotating the T-shaped core half body 14, the first rectangular conductor 21 is wound around the core middle leg 11, and the winding jig 34 is pushed in the direction of the flange portion 16, whereby the wound first rectangular conductor 21 is wound. The wide surfaces of are in close contact with each other. By winding the first flat conductor wire 21 around the core middle leg 11 in this manner, the first flat conductor wire 21 is formed in a spiral shape, and the first winding portion 21a is formed.

The above steps are also performed on the second rectangular conductor wire so that the first winding portion 21a and the second winding portion 23a have the core middle leg 1
As shown in FIG.
The transformer shown in (a) is formed.

As described above, the first member is directly attached to the core middle leg 11.
Since the rectangular conductor wire 21 and the second rectangular conductor wire 23 are wound, there is no gap between one end surface of the first rectangular conductor wire 21 and the second rectangular conductor wire 23 and the core middle leg 11, and the size of the transformer is reduced while maintaining the performance. Can be achieved.

(Third Embodiment) A third embodiment of the present invention will be described below. In the present embodiment, the first rectangular conductor wire 21 in the first embodiment is used.
Is obtained by stacking a plurality of thin-walled conductors and connecting them at their ends.

As shown in FIG. 7A, the first flat conductor wire 2
If the thickness of 1 is thick, the first rectangular conductor wire 21 linearly introduced by the slit 31 is sharply bent and wound in a spiral shape when it exits the slit 31 of the winding jig 30. Wrinkles may occur on the inside of the formed first rectangular conductor wire 21. When wrinkles occur in the first flat conductor wire 21 wound in this way, a gap may be formed between the first flat conductor wires 21 wound in a spiral shape. However, FIG.
As shown in (b), the first flat conductor wire 21 to be introduced into the slit 31 is formed by stacking the thin conductor wires 25, so that wrinkles do not occur at the exit of the slit 31 and the first flat conductor wires 21 are connected to each other. Can be wound closely.

The length of the core middle leg is Tw, the maximum thickness that can be wound on the core middle leg is Tp, and the core middle leg is wound around the core middle leg to obtain a desired inductance. If the number of turns of the rectangular conductor 21 is n, the number of turns n
Is determined by equation 1.

[0039]

[Formula 1] where Tp is the core material, transformer shape,
It is determined by the winding jig, rectangular wire material, etc.

The method of manufacturing the transformer in this case is as shown in FIG.
The details are the same as those in the first embodiment. FIG. 7D is an external view of the transformer.
7E shows a CC ′ cross section of FIG. 7D, and FIG. 7F shows an equivalent circuit diagram.

As described above, since the plurality of thin conductor wires 25 are stacked to form the first rectangular conductor wire 21, it is possible to suppress the generation of wrinkles due to the sharp bending at the time of winding, and to improve the productivity and the quality. Since the cross-sectional area of the first rectangular conductor wire 21 wound around the core middle leg 11 can be increased, a large current can be passed through the transformer. Further, the first rectangular conductor wire 21 which becomes a problem when the transformer is used at high frequency
The loss due to the skin effect of can be reduced.

(Fourth Embodiment) A fourth embodiment of the present invention will be described below with reference to FIG. In the present embodiment, according to the method for manufacturing the transformer in the first embodiment, the thick first flat rectangular conductor wire 21 is wound around the outer peripheral surface of the core middle leg 11 to form the spiral first winding portion 21a. In the same step, the thin second flat conductor wire 23 is wound around the outer peripheral surface of the core middle leg to form the spiral second winding portion 23a, and in the same step, the thick first flat wire 23 is formed.
A rectangular wire is spirally wound around the outer peripheral surface of the core middle leg 11 to form the first winding portion 21a. That is, the first winding portion 21a and the second winding portion 2 are arranged in a line in the axial direction of the core middle leg.
3a and the first winding portion 21a, and their end face portions are in close contact with each other.

8A is an external view of the transformer, FIG. 8B is a sectional view taken along the line DD ′ of FIG. 8A, and FIG. 8C is an equivalent circuit diagram. .

As described above, since the thick first winding portion 21a is formed so as to sandwich the thin second winding portion 23a, the cross-sectional area through which the magnetic flux passes can be increased.
It becomes possible to flow a large current through the transformer, and when the current value is the same, the loss due to the rectangular conductor wire can be reduced, and the efficiency of the transformer can be improved.

(Fifth Embodiment) The fifth embodiment of the present invention will be described below with reference to FIG. In the present embodiment, as shown in FIG. 9B, the I-shaped core half body 13, the E-shaped core half body 10, the core middle leg 11, and the first
A winding portion 21a and a second winding portion 23a are provided,
The I-type core half body 13 and the E-type core half body 10 are combined to form a closed magnetic circuit type transformer. Figure 9
9A is an external view of the transformer, FIG. 9B is a sectional view taken along line EE ′ of FIG. 9A, and FIG. 9C is an equivalent circuit diagram.

On the outer peripheral surface of the first winding portion 21a, in which the thin first flat conductor wire is wound directly around the core middle leg to form a spiral shape,
The thick second flat conductor wire is wound. Second
When winding the flat conductor wire around the outer peripheral surface of the first winding portion 21a, in the process of the first embodiment, the core middle leg 11 is used.
Is regarded as the first winding wire portion 21a, and the first rectangular conductor wire is regarded as the second rectangular conductor wire, the second winding wire portion 23 can be processed by substantially the same process.
It is possible to directly form a on the outer peripheral surface of the first winding portion 21a.

As described above, the second flat rectangular conductor wire having a thin wall is spirally wound around the outer peripheral surface of the first winding portion 21a in which the thin first flat conductor wire is spirally formed. Line part 21
Since no gap is created between the outer peripheral surface of a and the inner peripheral surface of the second winding portion 23a, the size of the entire transformer can be reduced. Further, when the size of the entire transformer is the same, the cross-sectional area of the flat conductor wire to be wound can be increased, so that the loss due to the flat conductor wire can be reduced and the conversion efficiency of the transformer can be improved. . This has the same effect even when there are three or more flat conductor wires wound around the core middle leg.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this embodiment and can be implemented in various forms.

[0049]

As described above, according to the power transformer of the first aspect of the present invention, the columnar core middle leg having electrical insulation and the surface insulation and the rectangular cross section are formed to have a width. Winding part in which a long first rectangular wire having a length direction and a thickness direction is formed in a spiral shape, and a second winding part in which a surface-insulated second rectangular wire is formed in a spiral shape,
And a first winding part having a first winding part.
Since the one end surface of the flat conductor wire is in close contact with the outer peripheral surface of the core middle leg, and the first flat conductor wire is wound so that the longitudinal direction of the first flat conductor wire is perpendicular to the axial direction of the core middle leg. The gap between the inner peripheral surface of the wire and the center leg of the core is reduced, which allows the transformer to be downsized without degrading the transformer performance. Conversely, if the transformer is the same size, the rectangular conductor Since the number of windings can be increased, the cross-sectional area of the flat conductor wire can be increased, and the conversion efficiency of the transformer can be improved.

According to the power supply transformer of the second aspect of the present invention, in addition to the effect of the first aspect of the invention, the rectangular conductor wire is formed by laminating a plurality of thin conductor wires in the thickness direction. When wound in a spiral shape, no gap is formed between the rectangular conductors, and it is possible to provide a transformer for a power supply with good productivity and quality.

According to the power supply transformer of the third aspect of the present invention, in addition to the effect of the first or second aspect of the invention, the first rectangular conductor wire is a thick rectangular conductor wire, and The 2 flat conductor wire is a long thin conductor wire having a rectangular cross section and having a width direction and a thickness direction.
The second winding portion is wound such that one end surface of the second flat conductor wire is in close contact with the outer peripheral surface of the core middle leg and the longitudinal direction of the second flat conductor wire is perpendicular to the axial direction of the core middle leg. The first middle part of the core of the second winding part,
Since the winding portions are formed so as to be in close contact with each other, the number of turns of the first winding portion can be increased and the cross-sectional area can be increased.
A large current can be passed through the power supply transformer, the loss due to the rectangular conductor can be reduced, and the conversion efficiency of the transformer can be improved.

According to the method for manufacturing a power supply transformer of claim 4 of the present invention, in addition to the effect of the invention of claim 1 or 2, the first flat conductor wire is a thin flat conductor wire. The second winding portion is a long thin flat conductor wire which has a rectangular cross section and has a width direction and a thickness direction, and one end face of the second flat conductor wire is an outer peripheral surface of the first winding portion. Since the second flat wire is wound so that the longitudinal direction of the second flat conductor wire is perpendicular to the axial direction of the core middle leg, the inner peripheral surface of the second winding part is Since it is in close contact with the outer peripheral surface, the coupling coefficient of the transformer can be increased,
The performance of the power transformer can be improved.

According to the method of manufacturing a power transformer according to claim 5 of the present invention, in addition to the effect according to the invention of claim 3 or 4, a thick rectangular conductor is provided on the primary side and thin. Since the flat conductor wire is the secondary side, the thick flat conductor wire is connected to the high current side, and the thin flat conductor wire is connected to the low current side, so that the loss due to the flat conductor wire can be further reduced and the transformer It is possible to improve the conversion efficiency.

According to the sixth aspect of the power supply transformer of the present invention, in addition to the effects of the first to fifth aspects, the end line portion of the first winding portion and the second winding portion are provided. The end wire portion of the first winding portion and the end wire portion of the second winding portion are pulled out to the side of the power transformer so as to sandwich the core middle leg. Since they can be separated from each other, it is possible to further secure the breakdown voltage.

According to the power transformer of claim 7 of the present invention, in addition to the effects of the inventions of claims 1 to 5, in addition to the end line portion of the first winding portion and the second winding portion, Since the end line part of the part is pulled out to the side of the power transformer in the same direction, when mounting the power transformer on the board, the core middle leg can be made horizontal to the board. It is possible to reduce the height and size of the power transformer.

According to the power transformer of claim 8 of the present invention, in addition to the effects of the inventions of claims 1 to 7, in addition to the core middle leg, the first winding portion, and the second winding portion. Is
Since both ends of the first flat conductor wire and both ends of the second flat conductor wire are resin-sealed, the moisture resistance and the insulation are improved, and it is possible to mount directly on the board. It is possible to reduce the height and size.

According to the method for manufacturing a power transformer according to claim 9 of the present invention, in manufacturing the power transformer according to claims 1 to 8, a hole having a diameter larger than the diameter of the core middle leg is formed. A manufacturing method for manufacturing using an air-core winding jig formed in a longitudinal direction, wherein an inserting step of inserting a core middle leg into a hole of the winding jig, A winding step of winding around the core middle leg so as to be in close contact with the outer peripheral surface of the core middle leg, and a pressing step of pressing the flat conductor wire close to the core middle leg in the axial direction of the core middle leg with a winding jig. Since the winding step and the pressing step are sequentially repeated, it is possible to stably wind one end surface of the rectangular conductor wire around the outer peripheral surface of the core middle leg, thereby manufacturing the power transformer with good productivity and quality. It becomes possible.

According to the method for manufacturing a power supply transformer of claim 10 of the present invention, in addition to the effect of the invention of claim 9, the winding jig has a slit formed in the longitudinal direction thereof. At the same time, before the winding step, there is also provided an introducing step of introducing the first flat conductor wire into the slit, and the winding step is performed while rotating the winding jig with the core middle leg as the rotation axis. It is possible to save the labor of holding the conductive wire, and more easily and stably manufacture the power transformer.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a power transformer according to the present invention.

FIG. 2 is a diagram showing a method of manufacturing the power transformer.

FIG. 3 is a diagram showing another embodiment of the power transformer.

FIG. 4 is a diagram showing a resin-encapsulated transformer for the power supply.

FIG. 5 is a diagram showing a second embodiment of a power supply transformer according to the present invention.

FIG. 6 is a diagram showing a method of manufacturing the power transformer.

FIG. 7 is a diagram showing a third embodiment of a power transformer according to the present invention.

[Equation 1] is an equation relating to the number of turns of the rectangular conductor of the power supply transformer.

FIG. 8 is a diagram showing a fourth embodiment of a power transformer according to the present invention.

FIG. 9 is a diagram showing a fifth embodiment of a power transformer according to the present invention.

[Explanation of symbols]

11 core middle leg 21 1st flat conductor wire 21a First winding part 22 Edge line 23 Second flat conductor wire 23a Second winding part 24 Edge line part 30 winding jig 31 slits 33 holes 34 Winding jig 35 holes

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiko Kinutani             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 5E002 AA05                 5E043 AB04

Claims (10)

[Claims] 1. A columnar core middle leg having electrical insulation,
A first winding portion, which is surface-insulated and has a rectangular cross-section, and has a long first rectangular conductor wire having a width direction and a thickness direction, which is formed in a spiral shape, and a surface-insulated second rectangular conductor wire. And a second winding portion formed in a spiral shape, wherein the first winding portion has one end surface of the first flat conductor wire closely contacting an outer peripheral surface of the core middle leg. In addition, the transformer for a power supply is characterized in that the first rectangular conductor wire is wound so that the longitudinal direction thereof is perpendicular to the axial direction of the core middle leg. 2. The power transformer according to claim 1, wherein the flat conductor wire is a plurality of thin conductor wires stacked in the thickness direction. 3. The first flat conductor wire is a thick flat conductor wire, and the second flat conductor wire is an elongated thin flat conductor wire having a rectangular cross section and having a width direction and a thickness direction. In the second winding portion, one end surface of the second flat conductor wire is in close contact with the outer peripheral surface of the core middle leg, and the longitudinal direction of the second flat conductor wire is in the axial direction of the core middle leg. It is wound so as to be vertical, and the first winding portion is formed in close contact with both axial end surfaces of the core middle leg of the second winding portion. The power supply transformer according to claim 1 or 2. 4. The first flat conductor wire is a thin flat conductor wire, and the second winding portion is an elongated thin flat conductor wire having a rectangular cross section and having a width direction and a thickness direction. And the one end surface of the second flat conductor wire is in close contact with the outer peripheral surface of the first winding portion, and the second flat conductor wire is wound such that the longitudinal direction is perpendicular to the axial direction of the core middle leg. The transformer for power supply according to claim 1 or 2, wherein the transformer for electric power is provided. 5. The power supply transformer according to claim 3, wherein the thick-walled rectangular conductor wire is on the primary side and the thin-walled rectangular conductor wire is on the secondary side. 6. The end wire portion of the first winding portion and the end wire portion of the second winding portion are drawn out to the side of the power transformer so as to sandwich the core middle leg. The power supply transformer according to any one of claims 1 to 5, wherein: 7. The end wire portion of the first winding portion and the end wire portion of the second winding portion are drawn to the side of the power supply transformer in the same direction. The power supply transformer according to any one of claims 1 to 5. 8. The resin encapsulation of the core middle leg, the first winding portion, and the second winding portion with both ends of the first rectangular conductor wire and both ends of the second rectangular conductor wire led out. The power supply transformer according to any one of claims 1 to 7, which is provided. 9. In manufacturing the power supply transformer according to any one of claims 1 to 8, an air-core winding treatment in which a hole having a diameter larger than a diameter of the core middle leg is formed in a longitudinal direction. A manufacturing method of manufacturing using a tool, the inserting step of inserting the core middle leg into the hole of the winding jig,
A winding step of winding the first rectangular conductor wire around the core middle leg so that one end surface of the first rectangular conductor wire closely contacts the outer peripheral surface of the core middle leg; And a pressing step of pressing in the axial direction of the core middle leg according to the above, wherein the winding step and the pressing step are sequentially repeated. 10. The winding jig has a slit formed in a longitudinal direction thereof, and further comprises an introducing step of introducing the first rectangular wire into the slit before the winding step. The method for manufacturing a power transformer according to claim 9, wherein the winding step is performed while rotating the winding jig with the core middle leg as a rotation axis.