JPH04251905A - Production of transformer - Google Patents

Abstract

PURPOSE:To facilitate the production of a miniatuarized transformer and facilitate the line production by forming a conductive pattern on a printed board, laminating the printed boards, integrating the laminates, forming a coil by connecting the conductive patterns and providing the laminate with a ferrite core. CONSTITUTION:A plurality of sections 1a, 1b... are produced on the both planes of a printed board 1, and spiral conductive patterns are formed on the sections 1a, 1b.... Conductive patterns are formed on the sections 1a, 1b... on one plane, and conductive patterns are formed on the sections 1a, 1b... on the other plane. Holes 5a-12a are through hole processed, the printed boards 11-15 are laminated and are integrated. The conductive patterns of the printed boards are connected, and an initial side coil and a secondary side coil are formed for each section. Then, a hole 23 is provided, a laminate is produced by cutting and separating each section, and ferrite cores 32 and 33 are incorporated into each laminate.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a transformer used, for example, in a high frequency switching power supply.

0002

[Prior Art] As seen in Japanese Utility Model Application Publication No. 2-88221, spiral conductive patterns are formed on a plurality of printed circuit boards, and a glass substrate is placed between the plurality of printed circuit boards on which these conductive patterns are formed. By laminating them with thin plate-like insulating material in between and connecting the conductive pattern ends of each printed circuit board using the through-hole method to form a primary coil and a secondary coil, and incorporating them into a ferrite core, one Those that manufacture transformers are known.

0003

[Problems to be Solved by the Invention] However, if a single transformer is constructed by forming a spiral conductive pattern on a printed circuit board, laminating it, and incorporating it into a ferrite core, it is difficult to construct a single transformer by forming a spiral conductive pattern on a printed circuit board. In manufacturing, the same assembly has to be repeated many times, which makes manufacturing troublesome and time-consuming. In particular, when manufacturing a very small transformer, positioning and the like when stacking layers is troublesome and difficult to realize.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a transformer, which can easily manufacture a plurality of very small transformers and can easily realize a production line.

[0005]

[Means and effects for solving the problems] The present invention provides spiral conductive patterns in a plurality of predetermined sections on a plurality of printed circuit boards, with different patterns between each printed circuit board, and on the same printed circuit board. The printed circuit boards with the same conductive pattern are laminated in a predetermined order with a film-like insulating adhesive layer sandwiched between them, and then the adhesive is applied using pressure and heat. The layers are cured to integrate the laminate, and then the conductive patterns in each section of each printed circuit board are divided into the primary and secondary sides for each section and connected to connect the primary and secondary coils. Terminal members to be connected to each coil end are fixed in each section of the integrated laminate, and then the laminate is separated into sections, and the laminate of each section is separated. The purpose is to manufacture a transformer by attaching a ferrite core to each.

[0006]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 1, a relatively large printed circuit board 1 is made of an epoxy resin board coated with copper foil on both sides.
A plurality of predetermined sections 1a, 1b, 1c...
A spiral conductive pattern is formed in each section 1a, 1b, 1c, . . . by etching. Further, reference holes 2a and 2b for positioning are opened in the center of both ends of the printed circuit board 1 in the longitudinal direction.

A conductive pattern 3 as shown in FIG. 2(a) is formed in each section 1a, 1b, 1c, . . . on one surface of one printed circuit board 11, and each section 1a, 1c on the other surface
A conductive pattern 4 shown in FIG. 2(b) is formed on portions b, 1c, . . . . Then, holes 3a and 4a are formed at the ends of each conductive pattern 3 and 4 by through-hole drilling. The holes 3a and 4a are the same hole, and a plated metal is deposited on the wall of the hole by through-hole plating to electrically connect the conductive patterns 3 and 4.

Further, a conductive pattern 5 shown in FIG. 3(a) is formed in each section 1a, 1b, 1c, . . . on one surface of another printed circuit board 12, and each section 1a, 1c on the other surface is
1b, 1c... have a conductive pattern 6 shown in FIG. 3(b).
form. Then, holes 5a and 6a are formed at the ends of each conductive pattern 5 and 6 by through-hole drilling. This hole 5
A and 6a are the same holes, and a plated metal is deposited on the walls of the holes by through-hole plating to electrically connect the conductive patterns 5 and 6.

Another printed circuit board 13 has a conductive pattern 7 shown in FIG. 4A in each section 1a, 1b, 1c, .
1b, 1c... have a conductive pattern 8 shown in FIG. 4(b).
form. Then, holes 7a and 8a are formed at the ends of each conductive pattern 7 and 8 by through-hole drilling. This hole 7
A and 8a are the same holes, and a plated metal is deposited on the walls of the holes by through-hole plating to electrically connect the conductive patterns 7 and 8.

Further, a conductive pattern 9 shown in FIG. 5A is formed in each section 1a, 1b, 1c, . . . on one surface of another printed circuit board 14, and each section 1a, 1c on the other surface is
1b, 1c... have conductive pattern 1 shown in FIG. 5(b).
form 0. Then, holes 9a and 10a are formed at the ends of each conductive pattern 9 and 10 by through-hole drilling. The holes 9a and 10a are the same hole, and a plated metal is deposited on the wall of the hole by through-hole plating to electrically connect the conductive patterns 9 and 10.

Each section 1a, 1b, 1c, .
A conductive pattern 11 shown in FIG.
A, 1b, 1c, . . . are formed with conductive patterns 12 shown in FIG. 6(b). Then, holes 11a and 12a are formed at the ends of each conductive pattern 11 and 12 by through-hole drilling. The holes 11a and 12a are the same hole, and the conductive patterns 11 and 12 are electrically connected by depositing plating metal on the walls of the holes by through-hole plating.

[0013] Since connecting terminal rods to be described later are inserted into the holes 3b, 6b, 8b, and 12b and soldered, through-hole processing necessary for soldering is performed later. Further, the holes 4b, 5b, 7b, 9b, 10b, and 11b will also be processed later through-hole processing.

In this way, a conductive pattern 3 is formed in each section on both sides.
The five printed circuit boards 1 having the circuit boards 1 to 12 formed thereon are stacked in the order shown in FIG. That is, conductive pattern 3 on one side,
Printed circuit board 11 with conductive pattern 4 formed on the other surface
Place the printed circuit board 12 with the conductive pattern 3 side facing up, and below that, place the printed circuit board 12 with the conductive pattern 5 formed on one side and the conductive pattern 6 on the other side, with the side facing the conductive pattern 5 facing up. A printed circuit board 13 with a conductive pattern 7 formed on one side and a conductive pattern 8 formed on the other side is placed below it with the side facing the conductive pattern 7 facing up, and below that a printed circuit board 13 with a conductive pattern 7 formed on one side and a conductive pattern 8 formed on one side is placed. A printed circuit board 14 having a pattern 9 and a conductive pattern 10 formed on the other surface is placed with the surface facing the conductive pattern 9 facing upward, and a conductive pattern 11 is formed on one surface and a conductive pattern 12 is formed on the other surface at the bottom. The formed printed circuit board 15 is placed with the surface facing the conductive pattern 11 facing upward.

[0015] A film-like adhesive layer (prepreg) 1 made of glass cloth impregnated with semi-cured epoxy resin is placed between the printed circuit boards 11 and 12.
31, an insulating adhesive layer 132 is similarly interposed between the printed circuit board 12 and the printed circuit board 13, and an insulating adhesive layer 133 is similarly interposed between the printed circuit board 13 and the printed circuit board 14. Similarly, an insulating adhesive layer 134 is interposed between the printed circuit board 14 and the printed circuit board 15.

Further, the upper surface of the printed circuit board 11, that is, the surface on the conductive pattern 3 side, and the printed circuit board 15
The lower surface, that is, the surface on the conductive pattern 12 side, is covered with release films 141 and 142. Note that the adhesive layers 131 to 134 and the release films 141 and 142 have reference holes 2a for positioning,
A hole corresponding to 2b is opened.

The thus formed laminate is sandwiched between lamination jig plates 15 and 16 from both sides, and the lamination jig plates 15 and 16, each of the printed circuit boards 11 to 15, each of the adhesive layers 131 to 134, and the release film 141
, 142 through the reference holes 2a, 2b of the positioning pin 1.
7 and 18 are inserted.

Then, the outer surfaces of each of the lamination jig plates 15 and 16 are laminated and hot-pressed using lamination press platens 21 and 22 with cushion papers 19 and 20 sandwiched therebetween. By this lamination hot press, each of the adhesive layers 131 to 134 is liquefied and fluidized to fill the spaces between the conductor patterns of each of the printed circuit boards 11 to 15, and the printed circuit boards 11 to 15 are bonded together.

Subsequently, the adhesively fixed laminate is removed from each lamination jig plate 15, 16, and holes 4b, 5 are drilled into the laminate in each section 1a, 1b, 1c, . . . as shown in FIG.
b, 7b, 9b, 10b, and 11b are formed by through-hole processing, and each conductive pattern is connected to each hole by through-hole plating. At this time, holes 4b and 5b,
Since 7b and 9b, 10b and 11b are holes at the same position, conductive patterns 4 and 5 are electrically connected, conductive patterns 7 and 9 are electrically connected, and conductive patterns 10 and 11 are electrically connected. Connected.

As a result, the conductive patterns 3, 4, 5, and 6 are connected to form a primary coil, and the conductive patterns 8, 7, 9, 10, 11, and 12 are connected to form a secondary coil. will be done. At this time, the hole 3b
, 6b, 8b, and 12b are also processed through-holes.

[0021] When this through-hole processing is completed,
An insulating adhesive layer (prepreg) is placed on the holes 4b, 5b, 7b, 9b, 10b, 11b and the outermost conductive patterns 3 and 12, and is liquefied and fluidized using a lamination press to adhere and embed. Note that at this time holes 3b and 6
b, 8b, and 12b are not blocked.

Next, as shown in FIG. 9, each section 1a, 1b
, 1c, . . . are respectively opened with holes 23, . Also, each section 1a
, 1b, 1c, . . . are inserted into the holes 3b, 6b, 8b, 12b made by through-hole machining, and soldered by the solder dip method. In this way, each conductive pattern 3, 6, 8, 12
The other end of each is connected to the connecting terminal rod 24, thereby forming a connecting terminal to the outside. In this case, a surface mounting connection terminal 25 shown in FIG. 11 may be used instead of the connection terminal bar 24.

[0023] Subsequently, each section is separated by cutting along the two-dot chain line shown in Fig. 9 . In this way, a laminate for each section is obtained. In this laminated body, conductive patterns 3, 4, 5, and 6 each having two turns are connected to form a primary coil having eight turns in total, and conductive patterns 8, each having three turns, respectively.
7, 9, 10, 11, and 12 are connected to form a secondary coil with a total of 18 turns. The connection terminal connected to hole 3a and the connection terminal connected to hole 6a become the input terminals of the primary coil, and the connection terminal connected to hole 8a and the connection terminal connected to hole 12a become the input terminals of the secondary coil. It becomes the output terminal of. In this case, each conductive pattern is arranged so that the distance between the connection terminal connected to hole 3a and the connection terminal connected to hole 6a is different, and the distance between the connection terminal connected to hole 8a and the connection terminal connected to hole 12a is different. If you set the end position of
Primary terminals and secondary terminals can be easily distinguished.

As shown in FIG. 12, a pair of EE type ferrite cores 32 and 33 are incorporated into the thus separated laminate 31 to form a transformer. At this time, the central legs 32a and 33a of each ferrite core 32 and 33 are inserted into the hole 23.

As described above, in this embodiment, both sides of the relatively large printed circuit board 1 are divided into a plurality of sections 1a,
1b, 1c, . . . are determined, and a spiral conductive pattern is formed in each section 1a, 1b, 1c, . . . by etching. Then, a conductive pattern 3 is formed in each section 1a, 1b, 1c, . . . on one surface, and a conductive pattern 4 is formed in each section 1a, 1b, 1c, . . . on the other surface. Similarly, another printed circuit board 1
A conductive pattern 5 is formed in each section 1a, 1b, 1c, . . . on one surface, and a conductive pattern 6 is formed in each section 1a, 1b, 1c, . . . on the other surface. Similarly, a conductive pattern 7 is formed on each section 1a, 1b, 1c, . . . on one side of another printed circuit board 1.
A conductive pattern 8 is formed in each section 1a, 1b, 1c, . . . on the other surface. Similarly, a conductive pattern 9 is formed in each section 1a, 1b, 1c, . . . on one surface of another printed circuit board 1, and a conductive pattern 10 is formed in each section 1a, 1b, 1c, . Similarly, a conductive pattern 11 is placed in each section 1a, 1b, 1c, . . . on one side of another printed circuit board 1.
are formed, and a conductive pattern 12 is formed in each section 1a, 1b, 1c, . . . on the other surface.

[0026]The holes 5a, 6a, 7a, 8a, 9a,
After drilling through-holes 10a, 11a, and 12a,
An adhesive layer 131 is placed between each printed circuit board 11 to 15.
.about.134 in the form of a sandwich, and are integrated by applying pressure and heating. Furthermore, holes 3b, 6b, 8b
, 12b and holes 4b, 5b, 7b, 9b, 10b, 11
After forming through-holes 4b, 5b, 7b, 9b, 10b, 11, plating is performed using through-hole plating to connect the conductive patterns of each printed circuit board.
After insulating the conductive patterns 3 and 12 with an insulating adhesive layer, the connecting terminal rod 24 is inserted and soldered to form a primary coil and a secondary coil in each section.

After that, a hole 23 into which the central leg of the ferrite core is inserted is made, and finally, a plurality of laminates are produced by cutting and separating each section to form a primary coil and a secondary coil. A transformer is manufactured by incorporating ferrite cores 32 and 33 into each of the laminates. Therefore, identical transformers can be mass-produced relatively easily. This is particularly effective when manufacturing very small transformers. In addition, production lines can be easily realized.

In the above embodiment, holes 3b, 4b (5b), 6b, 7b (9b), 8 are formed by through-hole drilling.
After opening holes 4b, 10b (11b) and 12b and further plating, holes 4b, 5b, 7b, 9b, 10b, 1
1b and the conductive patterns 3 and 12 are insulated, and then the hole 2 is
3, but it is not necessarily limited to this,
Drill the hole 23 first, then mask the hole 23 and process the through holes to form the holes 3b, 4b (5b), 6b, 7.
b (9b), 8b, 10b (11b), 12b are opened and plated, and further holes 4b, 5b, 7b, 9b,
10b, 11b and the conductive patterns 3, 12 may be insulated. Further, although the hole 23 is opened after the connection terminal bar 24 is inserted and soldered, the reverse may be used. Next, another embodiment of the present invention will be described with reference to FIGS. 13 to 17.

In this method, a conductive pattern 43 shown in FIG. 13(a) is formed in each section on one surface of one printed circuit board, and a conductive pattern 43 shown in FIG. 13(b) is formed in each section on the other surface. Form 44. Further, a conductive pattern 45 shown in FIG. 14(a) is formed in each section on one surface of another printed circuit board, and a conductive pattern 46 shown in FIG. 14(b) is formed in each section on the other surface. Form. Further, a conductive pattern 47 shown in FIG. 15(a) is formed in each section on one side of another printed circuit board, and a conductive pattern 47 shown in FIG.
A conductive pattern 48 shown in (b) is formed.

Further, a conductive pattern 49 shown in FIG. 16(a) is formed in each section on one surface of another printed circuit board, and a conductive pattern 49 shown in FIG. 16(b) is formed in each section on the other surface. A pattern 50 is formed. Furthermore, a conductive pattern 51 shown in FIG. 17(a) is formed in each section of one surface of another printed circuit board, and a conductive pattern 51 shown in FIG. 17(b) is formed in each section of the other surface.
A conductive pattern 52 shown in FIG.

Holes 43a and 43b are formed at the ends of each conductive pattern 43 to 52 by through-hole drilling.
, 44a, 44b, 45a, 45b, 46a, 46b,
47a, 47b, 48a, 48b, 49a, 49b, 5
Set the positions of 0a, 50b, 51a, 51b, 52a, and 52b to the positions shown in the figure.

When the position of each hole is determined in this way, the hole 43
a and 44a, 45a and 46a, 47a and 48a, 49a
and 50a, 51a and 52a, 44b and 45b, 48b and 49b, and 50b and 51b are at the same position, but at different positions from other sets, and are not located at positions that overlap with the conductive patterns of each printed circuit board. . Also, hole 43b
, 46b, 47b, and 52b are not located at positions overlapping with other holes or conductive patterns of each printed circuit board.

Therefore, if the positions of the conductive patterns on each printed circuit board and the positions of the holes to be made at the ends of each conductive pattern are set in this way, the holes 43a, 44a, 4 on the printed circuit board can be adjusted as described above.
5a, 46a, 47a, 48a, 49a, 50a, 51
It is not necessary to process the through-holes a and 52a before laminating the printed circuit boards, and as shown in FIG. After laminating and fixing a release film on the surface on the conductive pattern 52 side, it becomes possible to process all the holes together as through holes. Therefore, manufacturing becomes easier, and production lines become easier.

[0034]

[Effects of the Invention] As detailed above, according to the present invention, it is possible to easily manufacture a plurality of transformers, particularly to easily manufacture very small transformers, and to easily realize production lines. A method for manufacturing a transformer can be provided.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a printed circuit board in an embodiment of the present invention.

FIG. 2 is a diagram showing a primary coil pattern in the same embodiment.

FIG. 3 is a diagram showing a primary coil pattern in the same embodiment.

FIG. 4 is a diagram showing a secondary coil pattern in the same example.

FIG. 5 is a diagram showing a secondary coil pattern in the same example.

FIG. 6 is a diagram showing a secondary coil pattern in the same example.

FIG. 7 is a diagram for explaining lamination pressure and heat treatment in the same example.

FIG. 8 is a diagram showing the through-hole processing position of the conductive pattern terminal portion in the same embodiment.

FIG. 9 is a diagram showing the processing position of the center leg insertion hole of the ferrite core in the same embodiment.

FIG. 10 is a diagram showing an example of a connection terminal in the same embodiment.

FIG. 11 is a diagram showing another example of the connection terminal in the same embodiment.

FIG. 12 is an exploded perspective view of the transformer in the same embodiment.

FIG. 13 is a diagram showing a primary coil pattern in another embodiment of the present invention.

FIG. 14 is a diagram showing a primary coil pattern in the same example.

FIG. 15 is a diagram showing a secondary coil pattern in the same example.

FIG. 16 is a diagram showing a secondary coil pattern in the same example.

FIG. 17 is a diagram showing a secondary coil pattern in the same example.

[Explanation of symbols]

1...Printed circuit board, 1a, 1b-...section, 3-12, 4
3-52... Conductive pattern, 31... Laminated body, 32, 33...
Ferrite core.

Claims (1)

[Claims] 1. A spiral conductive pattern is formed in a plurality of predetermined sections on a plurality of printed circuit boards, with different patterns between each printed circuit board and the same pattern on the same printed circuit board. Each printed circuit board on which a pattern has been formed is laminated in a predetermined order with a film-like insulating adhesive layer sandwiched between them, and then the adhesive layer is cured by pressure and heating to integrate the laminate. Then, the conductive patterns in each section of each printed circuit board are connected separately to the primary side and secondary side for each section.
A secondary coil and a secondary coil are formed, and terminal members connected to each coil end are fixed in each section of the integrated laminate, and then the laminate is separated into each section. A method for manufacturing a transformer, comprising: manufacturing a transformer by attaching a ferrite core to each of the separated laminates.