JPH08236365A - Flat-type transformer - Google Patents

Abstract

PURPOSE: To provide a flat-type transformer which is capable of being optionally set in dielectric strength and easily manufactured through a current technique. CONSTITUTION: A primary coil board 2 which is manufactured through such a manner that a coil pattern is printed on a both-sided printed board in the market with resist ink and then etched, a secondary coil board 4 manufactured through the same process as above, and insulating plates 1, 3, and 5 are prepared. The boards 1 to 5 are laminated interposing an adhesive sheet between them and thermocompressed into a laminate. The laminate is blanked into pieces of prescribed shape. The blanked pieces are fitted in cores 7 and 7, and the cores 7 and 7 are clamped with clampers 8 into a flat-type transformer. A flat-type transformer of this constitution is capable of being optionally set in dielectric strength by changing the insulating plates 1, 3, and 5 in material and thickness.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a switching power supply, D
The present invention relates to a plate-shaped transformer suitable for a C-DC converter, a signal driver relay driver, and the like.

[0002]

2. Description of the Related Art Conventionally, as a flat plate transformer, for example, in Japanese Utility Model Publication No. 6-9110, a primary coil is formed on one surface of a double-sided printed circuit board and a secondary coil is formed on the other surface. And a structure in which a core is penetrated by making a hole in the inner portion of the secondary coil. Further, in Japanese Utility Model Laid-Open No. 6-9111, one single-sided printed circuit board has one
A secondary coil is formed, a secondary coil is formed on the other one-sided printed circuit board, the two one-sided printed circuit boards are superposed, and the core is penetrated through the inner parts of the primary coil and the secondary coil. The configuration is disclosed. Further, in Japanese Unexamined Patent Publication No. 5-343245, as shown in FIG. 7, a two-layer primary plane coil is formed on one surface of an insulating substrate 74, and a two-layer secondary plane coil is formed on the other surface. There is disclosed a structure in which coils are formed, these coils are sealed with an insulating layer 72, and the periphery thereof is covered with a magnetic layer 71.

[0003]

According to the above-mentioned conventional examples, it is possible to provide a plate-shaped transformer. However, it is difficult to obtain sufficient withstand voltage between the primary coil and the secondary coil in the case of using a printed circuit board.
It cannot be used in DC converters, signal signal relay drivers, etc. Also, the one shown in FIG. 7 must use a new manufacturing technique.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a flat plate-shaped transformer in which the withstand voltage can be arbitrarily set and which can be easily manufactured by the existing technology. .

[0005]

To achieve the above object, in the present invention, an insulating plate is sandwiched between two printed circuit boards on which a coil is formed, and a core is penetrated inside the coil. Is a plate-shaped transformer as follows (1),
It is configured as in (2).

(1) A primary coil is formed on a printed circuit board and a hole is formed in an inner portion of the primary coil, and the primary coil board is superposed on the primary coil board. An intermediate insulating plate with holes drilled at the locations corresponding to the holes,
A printed circuit board laminated on the intermediate insulating plate, wherein a secondary coil is formed on the printed circuit board, and a hole corresponding to a hole of the intermediate insulating plate in the inner portion of the secondary coil is formed in a hole. A secondary coil substrate and holes in the primary coil substrate,
A flat plate transformer having a hole in the intermediate insulating plate and a core inserted in the hole in the secondary coil substrate.

(2) The intermediate insulating plate is a primary coil substrate, 2
The flat plate transformer according to (1), which is a printed circuit board having a portion extending outward from the next coil substrate, wherein an element is mounted on the portion extending outward.

[0008]

With the configurations (1) and (2) described above, the withstand voltage between the primary coil and the secondary coil can be arbitrarily set, and the printed circuit board can be easily manufactured by a normal processing technique. Furthermore, in the configuration of (2), related elements can be easily mounted.

[0009]

EXAMPLES The present invention will be described in detail below with reference to examples.

(Embodiment 1) FIG. 1 is a sectional view showing the construction of a "plate-shaped transformer" which is Embodiment 1, FIG. 2 is a perspective view of Embodiment 1, and this embodiment has a schematic construction. is there. It should be noted that FIGS. 1 to 6 showing the embodiment are all exaggerated in size for the sake of clarity, and particularly the thickness is shown thick.

First, the construction and manufacturing method of the essential parts of this embodiment will be described with reference to FIGS.

FIG. 4 (a) shows a commercially available double-sided copper-clad printed board with a through hole made of glass epoxy and having a thickness of 0.1 mm.
41 and 43 are copper layers, 42 is a glass epoxy layer, and 44 is a through hole. A resist ink is printed on the upper surface of the double-sided printed circuit board of FIG. 4A in a spiral coil pattern by a screen printing method, etching is performed, and the resist is removed to form a coil 45. Lead wires are formed on the lower surface of the printed board by the same processing method. The coil end and the lead wire end are connected by a through hole 44 (2 in FIG. 3).
4, see FIG. 4b).

Thus, the primary coil substrate and the secondary coil substrate shown in 2 and 4 of FIGS. 3 and 4 are obtained. Reference numerals 1 and 5 are upper and lower insulating plates made of glass epoxy having a thickness of 0.2 mm, and 3 is an intermediate insulating plate made of glass epoxy having a thickness of 0.5 mm. An adhesive sheet is sandwiched between the plates 1 to 5 described above, pressed and heated to form a laminated plate, and punched into a shape suitable for the E-shaped core 7.

The E-shaped core 7 is fitted into the punched laminated plate and the tightening tool 8 is attached as shown in FIGS. 1 and 2, whereby a "plate-shaped transformer" is completed.

As described above, the flat transformer of this embodiment can be easily manufactured by the existing technique, and the withstand voltage depends on the material, thickness, etc. of the upper insulating plate, the lower insulating plate and the intermediate insulating plate. It can be set arbitrarily.

(Embodiment 2) FIG. 5 is a diagram showing the construction of a "plate-shaped transformer" which is Embodiment 2. In FIG. In this embodiment, a printed circuit board is used as an intermediate insulating board, and required elements such as ICs are mounted on this board.

In FIG. 5, 51 is a primary coil substrate,
It is manufactured from a commercially available double-sided printed circuit board by the same processing method as in Example 1. In this embodiment, the coil 46 is formed on the lower surface of the substrate by the same processing method. A secondary coil substrate 53 is manufactured by the same processing method as that of the primary coil substrate 51. Reference numeral 52 denotes an intermediate substrate corresponding to the intermediate insulating plate of the first embodiment, and as shown in FIG. 6, has a portion extending further outside the primary coil substrate 51 and secondary coil substrate 53. A required wiring pattern is formed on the intermediate substrate 52 by a processing method similar to that of the coil substrates 51 and 53, and terminals 62 are formed on portions extending outward.

The respective substrates 51, 52, 53 are laminated in the same manner as in the first embodiment, resin coating layers 55 for insulation are provided on the upper and lower surfaces of the laminated plate, and punched into a required shape to form an E-shaped core. 7 is fitted and a fastener 8 is attached. An element 61 such as an IC is mounted on a portion of the thus-formed transformer that extends to the outside of the intermediate substrate 52, and the flat-plate transformer of this embodiment is completed.

As described above, in this embodiment, the same effect as that of the first embodiment can be obtained, and further, required elements can be easily mounted.

[0020]

As described above, according to the present invention,
It is possible to provide a plate-shaped transformer which can be easily manufactured by the existing technology and whose withstand voltage can be arbitrarily set.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment.

FIG. 2 is a perspective view of the first embodiment.

FIG. 3 is a diagram showing a main part of the first embodiment separated from each other.

FIG. 4 is a diagram showing a manufacturing method of essential parts of Example 1;

FIG. 5 is a diagram showing a configuration of a second embodiment.

FIG. 6 is a perspective view of the second embodiment.

FIG. 7 is a diagram showing a configuration of a conventional example.

[Explanation of symbols]

 2 primary coil substrate 3 intermediate insulating plate 4 secondary coil substrate 7 core

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location 9375-5E H01F 31/00 H

Claims (2)

[Claims] 1. A primary coil is formed on a printed circuit board,
A primary coil substrate having a hole formed in an inner portion of the primary coil, an intermediate insulating plate that is superposed on the primary coil substrate and has a hole corresponding to a hole of the primary coil substrate, and an intermediate plate A printed circuit board overlaid on an insulating plate, in which a secondary coil is formed on the printed circuit board, and a hole is formed in a portion corresponding to a hole of the intermediate insulating plate in an inner portion of the secondary coil. A flat plate-shaped transformer comprising a substrate and a core inserted in the hole of the primary coil substrate, the hole of the intermediate insulating plate, and the hole of the secondary coil substrate. 2. The intermediate insulating plate is a printed circuit board having a portion extending outward from the primary coil substrate and the secondary coil substrate, and an element is mounted on the portion extending outward. The flat plate transformer according to claim 1.