JP3298170B2 - Transformer mounting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting a transformer used in various electronic devices.

[0002]

2. Description of the Related Art In recent years, transformers have been used for video equipment, audio equipment,
Used in home appliances and office equipment.

[0003] A conventional transformer mounting method will be described below. In FIG. 9, a transformer main body configured by incorporating a magnetic core 3 in a winding portion in which a winding 2 is wound around a bobbin 1 is mounted on a circuit board 4, and terminals 5 and the circuit board 4 are connected by solder 6. The mounting surface of the substrate 4 is sealed with a potting resin 7.

Further, as shown in FIG. 10, a transformer main body is housed in an insulating case 8 having an opening on one side, and a filler 9 filled with the filling material up to the opening surface of the insulating case 8 is mounted on a circuit board 4 and a terminal 5 is formed. And the circuit board 4 are connected by solder 6 and then the mounting surface of the circuit board 4 is sealed with a potting resin 7 in some cases.

[0005]

However, in the above configuration, the winding portion is not sealed by the potting resin 7 as shown in FIG. Had a problem of deterioration.

A transformer having a structure in which a transformer body as shown in FIG. 11 is housed in an insulating case 8 having an opening on one surface and housed together with a filler 9 is mounted on the circuit board 4, and the mounting surface of the circuit board 4 is potted with a potting resin 7. When sealing with air, the air 1 in the insulating case 8 when the filling of the filler 9 is insufficient is
0 has a problem that air bubbles 11 are generated in the potting resin 7 and the waterproof performance is degraded, and as shown in FIG.
It is necessary to use a transformer in which the filler 9 is injected over the entire opening surface of the transformer, and there is a problem that the injection of the filler 9 at the time of manufacturing the transformer is extremely difficult.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and does not impair the workability during the production of a transformer. The transformer is mounted on a circuit board and the mounting surface of the circuit board is sealed with a potting resin. It is another object of the present invention to provide a transformer mounting method for improving waterproof performance.

[0008]

In order to achieve this object, a method of mounting a transformer according to the present invention is a method of mounting a transformer in which a transformer body is housed together with a filler in an insulating case having an opening on one side together with a filler. The transformer is mounted on a circuit board having holes with the opening of the insulating case floating above the circuit board surface, and the transformer and the mounting surface of the circuit board are sealed with a potting resin.

[0009]

According to this method, even if the amount of the filler in the insulating case is small, the potting resin flows into the insulating case of the transformer from the inflow hole of the circuit board, and the air in the insulating case is removed from the circuit board at the opening of the insulating case. The circuit board on which the transformer is mounted can be completely sealed with the potting resin without air bubbles being generated on the potting surface by being discharged from the attached gap while floating from the mounting surface.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

First, FIG. 1 and FIG. 2 will be described. An insulating case 1 having an opening on one side of a transformer body constituted by incorporating a magnetic core 14 in a winding portion in which a winding 13 is formed on a bobbin 12.
A circuit board 19 having an inflow hole 18 for a potting resin 17 and a transformer housed in the container 5 together with the filler 16.
The terminal 20 and the circuit board 19 are soldered to each other with the opening of the insulating case 15 floating above the surface of the circuit board 19.
Then, the transformer and the mounting surface of the circuit board 19 are sealed with a potting resin 17.

FIG. 3 shows a state in which the opening of the insulating case 15 is floated from the surface of the circuit board 19 by housing the insulating body 15 together with the filler 16 in which the transformer body is provided with the mounting feet 22 projecting toward the circuit board. When sealing with the potting resin 17, the inflow hole 1 of the circuit board 19 is formed.
8, the potting resin 17 flows into the insulating case 15 and is discharged from the gap a between the insulating case 15 and the circuit board 19, so that even if the amount of the filler 16 is small, the potting resin 17 is sealed without generating bubbles. As a result, the transformer body and the filler 16 can be easily stored in the insulating case 15, thereby improving the insulation performance and the waterproof performance of the transformer, and the potting resin 17 from the inflow hole 18 of the circuit board 19. Flows into the insulating case 15 and fixes the transformer body and the insulating case 15 to increase the drop strength of the transformer.

FIG. 4 is a perspective view of the insulating case 15 of FIG. FIG. 5 shows a transformer mounted with the projection 23 of the circuit board 19 so that the opening of the insulating case 15 is raised above the surface of the circuit board 19.
After the connection of the transformer 9 with the solder 21, the transformer and the mounting surface of the circuit board 19 are sealed with a potting resin 17.

FIG. 6 shows the circuit board 19 and the projection 23 of FIG.
It is a perspective view of. FIG. 7 shows a circuit board 1 having a transformer terminal 24 having a length in contact with the circuit board 19.
9, the terminal 20 and the circuit board 19 are similarly connected by the solder 21, and the mounting surface of the transformer and the circuit board 19 is potted with the potting resin 17. It is configured by sealing.

FIG. 8 shows a transformer mounted on the bobbin 12 with a projection 25 provided so as to be in contact with the circuit board 19 so that the opening of the insulating case 15 is floated from the surface of the circuit board 19. After connecting the board 19 with the solder 21, the transformer and the mounting surface of the circuit board 19 are sealed with a potting resin 17.

[0016]

As described above, according to the present invention, a transformer constructed by housing a transformer body having a magnetic core incorporated in a winding portion together with a filler in an insulating case having an opening on one surface is provided with an inlet hole of a potting resin. By mounting the transformer on the circuit board with the opening of the insulating case floating above the circuit board surface and sealing the mounting surface of this transformer and the circuit board with potting resin, a small amount of filler The transformer body can be housed in an insulating case, and the mounting surface of the transformer and the circuit board can be sealed with potting resin so that air bubbles do not occur. Excellent workability.

Further, the potting resin flows into the insulating case of the transformer through the inflow hole of the potting resin and fixes the insulating case and the transformer, so that the transformer has excellent drop strength.

As described above, it is possible to realize a highly reliable transformer mounting method excellent in insulation performance, waterproof performance and drop strength of the transformer.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a transformer mounting method according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view before mounting.

FIG. 3 is a sectional view showing a method of mounting a transformer according to another embodiment.

FIG. 4 is a perspective view of the insulating case of the embodiment.

FIG. 5 is a sectional view showing a method of mounting a transformer according to still another embodiment.

FIG. 6 is a perspective view of the circuit board of the embodiment.

FIG. 7 is a sectional view showing a method of mounting a transformer according to another embodiment.

FIG. 8 is a sectional view showing a method of mounting a transformer according to still another embodiment.

FIG. 9 is a sectional view showing a conventional transformer mounting method.

FIG. 10 is a sectional view showing another conventional transformer mounting method.

FIG. 11 is a cross-sectional view illustrating a method for mounting another conventional transformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Bobbin 13 Winding 14 Magnetic core 15 Insulating case 16 Filler 17 Potting resin 18 Inflow hole 19 Circuit board 20 Terminal 21 Solder 22 Mounting foot 23 Projection 24 Terminal 25 Projection

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01F 27/28 H01F 27/32 H05K 1/18

Claims (5)

(57) [Claims] A transformer constructed by housing a transformer body having a magnetic core incorporated in a winding portion wound on a bobbin together with a filler in an insulating case having an opening on one side is provided with a transformer having an inlet hole for potting resin. A method for mounting a transformer, wherein the mounting portion of the transformer is mounted on a circuit board having the opening of the insulating case floating above the circuit board surface, and the mounting surface of the transformer and the circuit board is sealed with a potting resin. 2. The method of mounting a transformer according to claim 1, wherein the insulating case is provided with mounting feet protruding from the opening surface to the circuit board surface side, so that the opening of the insulating case floats above the circuit board surface. 3. The transformer mounting method according to claim 1, wherein a projection is provided between the opening surface of the insulating case and the circuit board so that the opening surface of the insulating case is raised above the circuit board surface. 4. The semiconductor device according to claim 1, wherein the insulating case is mounted so that an opening surface of the insulating case floats with respect to a circuit board surface by using a terminal of the transformer.
How to implement the described transformer. 5. The method of mounting a transformer according to claim 1, wherein the insulating case is mounted so that an opening surface of the insulating case floats with respect to a circuit board surface using a bobbin of the transformer.