JP2000091134A - Converter transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a converter transformer which can reduce costs due to elimination of a voltage stabilizer and also can be manufactured in a short time due to easy assembly. SOLUTION: A first region 115A of a cylindrical part 114 of a bobbin 110 is wound around by a primary winding 130, and a secondary region 115B is wound around by a 1st secondary winding 140 and a 2nd secondary winding 150. A 2nd terminal row 170 and a 3rd terminal row 180 are constituted so as to hold a leg part 122 of a core 120 between them. A starting point of winding the primary winding 130 and an ending point for winding up the primary winding 130 are connected to a pair of terminal pins 113 of a first terminal row 160. A starting point of the 2nd secondary winding 150 which has 2.5 turns as the number of windings is connected to the terminal pin 113 of the 3rd terminal row 180, and an ending point of winding up is connected to the terminal pin 113 of the 2nd terminal row 170.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a converter transformer used for, for example, a switching power supply.

[0002]

2. Description of the Related Art Conventionally, converter transformers have been used for switching power supplies and the like. The single-output type converter transformer outputs a single voltage, for example, 5V. As shown in FIG. 6A, the single-output type converter transformer 10 has a primary winding 12 and a secondary winding 14,
Commercial power rectified by, for example, a rectifier circuit is applied to the input terminals 12A and 12B on the primary side, and a voltage (for example, 5 V) is output from the output terminals 14A and 14B on the secondary side. Here, the secondary winding 14 has, for example, one turn (T).

On the other hand, a multi-output type converter transformer has two
It outputs two or more different voltages, for example, 5V and 15V. As shown in FIG. 6B, a multi-output type converter transformer 20 includes a primary winding 22 and two secondary windings 2.
4 and 26, a commercial power rectified by, for example, a rectifier circuit is applied to the primary-side input terminals 22A and 22B,
A first voltage (for example, 5 V) is supplied from one of the output terminals 24A and 24B on the secondary side to the other output terminals 26A and 26A on the secondary side.
6B to output a second voltage (for example, 15 V). Here, one secondary winding 24
Is one turn (T), for example, and the other secondary winding 26 is, for example, three turns (T). However, if the switching power supply is designed to output 5V and 12V, it is necessary to convert the 15V output voltage output from the converter transformer 20 to 12V by a constant voltage circuit. In this case, providing a constant voltage circuit increases the cost,
There is also a problem that power loss is caused by the constant voltage circuit.

Therefore, a converter transformer as shown in FIG. 7 is used in a multi-output type switching power supply that outputs 5 V and 12 V. In FIG.
The converter transformer 30 has a primary winding 32 and two secondary windings 34 and 36, and primary-side input terminals 32A and 32.
6B is similar to the configuration of FIG. 6B in that a commercial power rectified by, for example, a rectifier circuit is applied to B. However, by setting one secondary winding 34 to one turn (T) and the other secondary winding 36 to 2.5 turns (T), 5 V and 1
A voltage of 2.5 V is obtained. If the voltage is 12.5 V, a constant voltage circuit is unnecessary. FIG. 8 is an assembly view of the converter transformer of FIG. As shown in FIG. 8, the input terminals 32A and 32B on the primary side of the converter transformer 30 are arranged at one side of the base 39 of the bobbin 38, and the output terminals 34A, 34B, 36A and 36B on the secondary side are connected to each other. Bobbin 3
8, that is, at a position opposite to the primary-side input terminals 32A and 32B with the core 40 interposed therebetween.

[0005]

However, 12.
In order to obtain an output of 5V, the other secondary winding 36 is connected to 2.5V.
In the converter transformer 30 which is a turn, the wire 42 must be connected between the end of the winding of the secondary winding 36 (the winding start) and the output terminal 36A (36B) on the secondary side. As shown in FIG. 8, this wire 42 has to be routed around the upper part of the core 40 due to the arrangement of the output terminals 36A (36B) on the secondary side. In addition, a transformer used for a switching power supply is required to secure a predetermined creepage distance between primary and secondary windings according to safety standards of various countries. For this reason, the above-mentioned wire is
It is necessary to pass the tube 44 in order to ensure insulation from the tube 44. Then, after the core 40 is assembled into the bobbin 38, the wire 42 and the end of the winding (starting of winding) of the secondary winding 36 and the output terminal 36A (36B) on the secondary side are subjected to a soldering process. Is being processed. These operations are very complicated, require many man-hours, and increase costs. SUMMARY OF THE INVENTION It is an object of the present invention to provide a converter transformer that does not require a constant voltage circuit, reduces costs, and is easy to assemble and can be manufactured in a short time.

[0006]

According to the present invention, a primary winding and a secondary winding are wound on a bobbin having a core incorporated therein, and the secondary winding has a winding number of ( 0.5+
In the converter transformer configured to have N) turns (where N is a natural number), the bobbin is provided with first, second, and third terminal rows each including a plurality of terminal pins, and the second and third terminal rows are provided. A terminal row is configured to sandwich the core,
The starting point of the secondary winding is connected to one of the terminal pins of the second terminal row and the terminal pin of the third terminal row, and the ending point of the second secondary winding is connected to the second terminal row. It is characterized in that it is connected to the other of the terminal pins of the terminal row and the terminal pins of the third terminal row.

In the present invention, since the second and third terminal rows are configured so as to sandwich the core, the number of turns is (0.5+
N) A winding start and a winding end of the secondary winding configured to have a turn (where N is a natural number) can be connected to one and the other of the second and third terminal rows, respectively. Therefore, since the output voltage can be output by the secondary winding having the number of turns of 0.5 turns, a constant voltage circuit or the like for adjusting the output voltage is unnecessary. In addition, even in the case of a secondary winding having a number of turns of 0.5 turns, complicated work such as wiring around the upper part of the core to connect between the secondary winding and the terminal pin. Is not required, and assembly is easy and it can be manufactured in a short time.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing an assembled state of a converter transformer according to a first embodiment of the present invention. FIG. 1 (A) is a side view, and FIG. 1 (B) is FIG. 1 (A).
1 (A) is an arrow A view, and FIG. 1 (C) is an arrow B view of FIG. 1 (A). FIG. 2 is a circuit diagram of the converter transformer according to the first embodiment. FIG. 3 is a diagram illustrating a configuration of a second secondary winding according to the first embodiment. FIG. 3A is a conceptual diagram of the winding.
FIG. 3B is a circuit diagram of a portion corresponding to FIG.

First, the configuration of a converter transformer according to a first embodiment will be described with reference to FIGS. FIG. 1C shows a state where the primary winding, the first and second secondary windings are not wound, and the number of connection pins 113 described later is omitted. The converter transformer 100 includes a bobbin 110, a core 120, a primary winding 1
30, a first secondary winding (corresponding to "another secondary winding" in the claims) 140, a second secondary winding (corresponding to a "secondary winding" in the claims) 150, first to third terminal rows 1
60, 170, 180 and the like.

The bobbin 110 includes a plate-like base portion 112 having a substantially rectangular shape in a plan view, and a cylindrical portion 114 extending from one surface of the base portion 112 in a direction perpendicular to the surface.
And The core 120 has an E shape, and has a central leg 122 and left and right legs 124 and 126 sandwiching the central leg 122.
have. Then, the center leg 122 is connected to the cylindrical portion 11.
4, it is disposed so as to extend in the direction in which the cylindrical portion 114 extends.

An outer peripheral surface 115 of the cylindrical portion 114 has a substantially rectangular flange portion 116 in a plan view that divides the outer peripheral surface into first and second regions 115A and 115B at an intermediate portion in the extending direction of the cylindrical portion 114. Is provided. This flange portion 116
As shown in FIG. 1A, the one side end 116A extends in the horizontal direction so that it is located at substantially the same horizontal position as a comb-shaped tip portion 112A of the base portion 112 described later.
Further, a flange portion 117 forming an edge of the first region 115A is provided at an upper end portion of the cylindrical portion 114. That is, the first region 115A is located on the opposite side of the base 112 from the second region 115B. Flange part 11
6 and 117, a primary winding 130 is wound around a first region 115A, and the upper surface of the base 112 is
The second area 115B divided by the first and second 16
Next windings 140 and 150 are wound.

As shown in FIG. 1A, a first, second, and third terminal rows 160, 170, and 180 are provided on a base 112 so as to protrude downward from the lower surface thereof. It is composed of terminal pins 113. As shown in FIG. 1B, first, second, and third terminal rows 160, 170,
Reference numeral 180 denotes a configuration in which a plurality of terminal pins 113 are respectively located on three straight lines extending in parallel in this order at intervals. Then, the second and third terminal rows 17
Numerals 0 and 180 are configured to sandwich the leg 122 of the core 120. Therefore, the cylindrical portion 114 is the second terminal row 1
It is located between 50 and the third terminal row 160. Further, the portion of the base portion 112 where the terminal pins 113 of the first terminal row 160 are disposed has a comb-like shape in a plan view, and the terminal pin of the first terminal row 160 has a tip 112A at the comb-like portion. 130 is provided, and the base end portion 1 of the comb-like portion is provided.
The terminal pins 130 of the second terminal row 170 are provided on 12B. A gap 112C is formed between the comb-shaped portions.
Are formed.

In the converter transformer 100 according to the first embodiment, the commercial power rectified by the rectifier circuit is applied to the primary winding 130, and the first voltage (5V) is applied from the first secondary winding. Are output for two sets, and the second 2
It is assumed that the second winding outputs the second voltage (12.5 V) for two sets.

As shown in FIG. 2, the start and end positions of the primary winding 130 are determined by the first terminal row 160.
Are connected to a pair of terminal pins 113-1 and 113-2. The wiring state of the primary winding 130 will be described with reference to FIG. 1A. The starting point and the ending point of the winding of the primary winding 130 are the wire 130A, that is, the end of the primary winding 130. The first is located vertically downward along the upper surface of the flange 116 from the end of the flange 116.
A pair of terminal pins 113-1 and 113-2 of the terminal row 160
It is connected to the.

The number of turns of each of the first secondary windings 170 is one.
It is a turn. The start and end points of one set of the first secondary winding 140 are connected to a pair of terminal pins 113-3 and 113-4 included in the third terminal row 180, and the other set is connected to the other set. The start and end of winding of the secondary winding 140 are determined by the terminal pins 113-5 and 113-4.
It is connected to the. In FIG. 2, “•” indicates a winding start position of the winding.

On the other hand, the number of turns of the second secondary winding 150 is 2.5 turns. The start position of the second secondary winding 150 is connected to the terminal pin 113-6 of the third terminal row 180, and the end position of the second secondary winding 150 is connected to the terminal pin 113-7 of the second terminal row 170. . The start of the winding of the second secondary winding 150 of the other set is connected to the terminal pin 113-7 of the second terminal row 170, and the end of the winding is the terminal pin 113-8 of the third terminal row 180. It is connected to the.

FIG. 3A shows the second secondary winding 1 described above.
FIG. 3B shows a circuit of a portion corresponding to FIG. 3A. That is, the starting point of the winding of the second secondary winding 150 shown by the solid line is connected to the terminal pin 113-6 of the third terminal row 180, and the second secondary winding 15
When “0” is wound around the core 122 by 2.5 turns, the end of the winding is guided to the position facing the second terminal row 170. By connecting the end of the winding to the terminal pin 113-7 of the second terminal row 170, a set of second secondary windings is formed. Then, using the terminal pin 113-7 as an intermediate tap, the starting point of another set of the second secondary winding 150 indicated by a dashed line is connected, and the second secondary winding 150 is connected to the core. When winding is performed around 122 for 2.5 turns, the end portion of the winding is guided to the portion facing the third terminal row 180. By connecting the end of this winding to the terminal pins 113-8 of the third terminal row 180, another set of second secondary windings is formed.

As described above, when the number of turns of the second secondary winding 150 includes a fraction of 0.5 turn such as 2.5 turns, the second secondary winding 150 is located at a position sandwiching the core 122 of the bobbin 120. The winding start and end positions of the second secondary winding 150 are derived at the positions facing the second and third terminal rows 170 and 180. Therefore, the second secondary winding 150
Of the winding start and end of the second and third terminal rows 17
What is necessary is just to connect to the connection pins 130 of 0 and 180, respectively, and unlike the related art, there is no need for complicated work such as wiring around the upper part of the core.

Referring to FIGS. 1A and 1B, the second
The wiring state of the secondary winding 150 of FIG. 3 will be described. Of the winding start or end of the second secondary winding 150, the terminal pins 113 of the second terminal row 170 (FIGS. )
The wiring of the portion connected to the terminal pin 113-7) is formed by a gap 112 between the comb-shaped portions of the base portion 112.
This is done through C.

As shown in FIG. 1A, the primary winding 130 is connected to the terminal pins 113 of the first terminal row 160, and the first and second terminals are connected to the terminal pins 113 of the second terminal row 170. 2
Of secondary windings 140 and 150 are connected. Therefore, a predetermined creepage distance is ensured between the first terminal row 160 and the second terminal row 170, that is, between the terminal pins 113. In addition, as described above, the wiring of the portion connected to the terminal pin 113 of the second terminal row 170 of the second secondary winding 150 is performed through the gap 112C of the base 112 so that the primary winding 130 First terminal row 1
The wire 130A that connects between the terminal pins 113 of the second terminal row 170 and the wire rod 130A that connects between the terminal pins 113 of the second terminal row 170.
The above-mentioned predetermined creepage distance is secured between the wiring portion and the wiring portion that connects between the two.

According to the converter transformer 100 configured as described above, when the rectified predetermined commercial power is input between the input terminal of the primary winding 130, that is, the terminal pins 113-1 and 113-2. A voltage of 5 V is output between the output terminals of the first secondary winding 140, that is, between the terminal pins 113-3 and 113-4, and between the terminal pins 113-4 and 113-5. The output terminal of the line 150, that is, between the terminal pins 113-6 and 113-7, the terminal pin 113
A voltage of 12.5 V is output between −7 and 113-8.
The two sets of 5V voltages and the two sets of 12.5V voltages are supplied to a power supply circuit at a subsequent stage to generate a desired voltage output. In the first embodiment described above, the second secondary winding 1
Although the winding start and end positions of 40 are a pair of connection pins included in the third terminal row, it is needless to say that a pair of connection pins included in the second terminal row may be used.

FIG. 4 is a view showing an assembled state of the converter transformer according to the second embodiment. FIG. 4 (A) is a side view, and FIG. 4 (B) is a C view of FIG. 4 (A). is there. In the second embodiment, the number of terminal pins in each terminal row of the converter transformer 100A is different from each other. More specifically, a total of five terminal pins 113 of the first terminal row 160 are provided on each of the distal end portions 112A with five comb-shaped portions of the base portion 112. Second terminal row 170
And six terminal pins 113 of the third terminal row 180 are provided. That is, the primary winding 13
The first, second, and third secondary windings 140 and 150 are different depending on the number of sets of the secondary windings 140 and 150 and the position of the terminal pin 113 connecting the start and end of winding. It is possible to set the number of terminal pins of the terminal rows 160, 170, 180, respectively.

FIG. 5 is a view showing an assembled state of the converter transformer according to the third embodiment. FIG. 5 (A) is a side view, and FIG. 5 (B) is a view D in FIG. 4 (A). is there. In the third embodiment, one of the converter transformers 100B
In order to ensure insulation between the primary winding 130 and the first and second secondary windings 140 and 150, the primary winding 130 and the first and second secondary windings 140, The portion facing 150 is constituted by the insulator 118A. Also,
In order to secure insulation between the core 140 and the primary winding 130 and the first and second secondary windings 140 and 150, the cylindrical portion 1
14 and the primary winding 130 and the first and second
The insulator 118B is provided between the secondary windings 140 and 150. The entire flange portion 116 is formed of an insulator 118.
Of course, A may be used. As the insulators 118A and 118B, it is preferable to use a resin material having excellent insulating properties and strength, such as PBT or PET. This is because, in this type of converter transformer, the base portion 112 and the cylindrical portion 114 constituting the bobbin 110 are made of a phenol resin having excellent heat resistance but somewhat fragile properties in consideration of soldering work. Because there are many.

In the first embodiment described above, the start and end of the winding of the first secondary winding 140 are a pair of connection pins included in the third terminal row. It goes without saying that a pair of connection pins may be included. In each of the above-described embodiments, the first 2
Although the number of turns of the secondary winding 140 is one turn and the number of turns of the second secondary winding is 2.5 turns, the present invention is not limited to this, and the number of turns of the first secondary winding 140 is not limited thereto. May be M turns (M is a natural number), and the number of turns of the second secondary winding 150 may be (N + 0.5) turns (N is a natural number). In addition, the converter transformer of the present invention includes the first
The secondary winding 140 is not always necessary, and a configuration having only the secondary winding 150 having (N + 0.5) turns as the secondary side may be adopted.

[0025]

As is clear from the above description, the present invention
A converter in which a primary winding and a secondary winding are wound around a bobbin in which a core is incorporated, and the secondary winding has a number of turns of (0.5 + N) turns (where N is a natural number). In the transformer, the bobbin is provided with first, second, and third terminal rows each including a plurality of terminal pins, and the second and third terminal rows are configured so as to sandwich the core. Is connected to one of the terminal pins of the second terminal row and the terminal pins of the third terminal row.
The end of winding of the next winding is configured to be connected to the other of the terminal pins of the second terminal row and the terminal pins of the third terminal row.

Therefore, in the present invention, since the second and third terminal rows are configured so as to sandwich the core, the number of turns is (0.5 + N) turns (where N is a natural number). The winding start and end of the secondary winding can be connected to one and the other of the second and third terminal rows, respectively. Therefore, the output voltage can be output by the secondary winding having the number of turns of 0.5 turns, which eliminates the need for a constant voltage circuit unlike the related art.
There is no power loss and the cost can be reduced. In addition, even in the case of a secondary winding having a number of turns of 0.5 turns, complicated work such as wiring around the upper part of the core to connect between the secondary winding and the terminal pin. Is not required, and assembly is easy and it can be manufactured in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing an assembled state of a converter transformer according to a first embodiment of the present invention, and FIG.
1B is a side view, and FIG. 1B is an arrow A view of FIG.
(C) is a B view of FIG. 1 (A).

FIG. 2 is a circuit diagram of a converter transformer according to the first embodiment.

3A and 3B are diagrams illustrating a configuration of a second secondary winding according to the first embodiment. FIG. 3A is a conceptual diagram of the winding, and FIG.
FIG. 3B is a circuit diagram of a portion corresponding to FIG.

FIG. 4A is a diagram showing an assembled state of the converter transformer according to the second embodiment, FIG. 4A being a side view, and FIG.
(B) is an arrow C view of FIG. 4 (A).

FIG. 5A is a diagram showing an assembled state of the converter transformer according to the third embodiment, FIG. 5A is a side view, and FIG.
(B) is an arrow D view of FIG. 4 (A).

6A and 6B are diagrams showing a conventional converter transformer, FIG. 6A is a circuit diagram of a single-output type converter transformer, and FIG. 6B is a circuit diagram of a multi-output type converter transformer.

FIG. 7 is a circuit diagram of another conventional converter transformer.

8 is an external view of the converter transformer of FIG.

[Explanation of symbols]

100, 100A, 100B ... Transformer transformer,
110 ... bobbin, 113 ... terminal pin, 120 ... core, 130 ... primary winding, 140 ... first secondary winding (another secondary winding), 150 ... second 2 Secondary winding (secondary winding), 160: first terminal row, 170: second terminal row,
180: Third terminal row.

Claims (10)

[Claims] 1. A primary winding and a secondary winding are wound around a bobbin in which a core is incorporated, and the number of turns of the secondary winding is (0.
5 + N) turns (where N is a natural number), wherein the bobbin is provided with first, second, and third terminal rows each including a plurality of terminal pins; The terminal row is configured so as to sandwich the core, and the starting point of the secondary winding is connected to one of the terminal pins of the second terminal row and the terminal pins of the third terminal row. A converter transformer, wherein the end of the next winding is connected to the other of the terminal pins of the second terminal row and the terminal pins of the third terminal row. 2. A secondary winding different from the secondary winding is provided, and the another secondary winding is configured so that the number of turns is M turns (where M is a natural number), The starting point and the ending point of the another secondary winding are connected to a pair of terminal pins included in the second terminal row or a pair of terminal pins included in the third terminal row. Characteristic converter transformer. 3. The device according to claim 2, wherein the cylindrical portion is connected to the second terminal row and the third terminal row.
3. The converter transformer according to claim 2, wherein the converter transformer is configured to be located at a position between the terminal rows. 4. One of the outer peripheral surfaces is located on a side opposite to the base portion with respect to the other region of the outer peripheral surface, and the first, second, and third terminal rows are provided. 3. The converter transformer according to claim 2, wherein the portion is the other surface of the base portion. 5. The converter transformer according to claim 2, wherein said flange portion is made of an insulator. 6. The converter transformer according to claim 2, wherein an insulator is provided between an outer peripheral surface of said cylindrical portion and said primary winding and said secondary winding. 7. A portion of the base portion where the terminal pins of the first terminal row are arranged has a comb-like shape in plan view, and a terminal of the first terminal row is provided at a tip end of the comb-like portion. A pin is provided, and a terminal pin of the second terminal row is provided at a base end portion of the comb-shaped portion, and a terminal pin of the second terminal row at a winding start position or a winding end position of the secondary winding is provided. 3. The converter transformer according to claim 2, wherein the connection to the terminal pin is made through a gap between the comb-shaped portions. 8. The converter transformer according to claim 1, wherein the distance between the first terminal row and the second terminal row is configured to be equal to or greater than a predetermined creepage distance. 9. The semiconductor device according to claim 1, wherein the number of terminal pins in at least one of the first, second, and third terminal rows is different from the number of terminal pins in the remaining terminal rows. The converter transformer according to claim 1. 10. A method according to claim 1, wherein said first, second, and third terminal rows are constituted by a plurality of terminal pins located on three straight lines extending in parallel in said order at intervals. The converter transformer according to claim 1, wherein