JPS6011615Y2 - flyback transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flyback transformer that supplies high voltage to a cathode ray tube of a television receiver.

Conventionally, when attaching a flyback transformer to a printed circuit board, the entire flyback transformer is housed in a case, which allows for stable fixation because the end face of the case has a large contact surface with the board. In the molded type of flyback transformer, a metal fitting with a U-shaped cross section was attached to the end of the flyback transformer, and the metal fitting was attached in contact with the printed circuit board.

That is, as shown in FIG. 1A, a terminal mounting portion 5 with a plurality of terminals 4 fixed thereto is attached to one end of a bobbin 3 with a core 1 inserted inside and a coil portion 2 (low/high voltage coil) wound around the outside. In the flyback transformer, the terminal mounting portion 5□
Attach the mounting bracket 6 with a U-shaped cross section to the side of the first core on the side.
When the terminal 4 is inserted into the insertion hole of the printed circuit board, the end surfaces of the bent pieces 7 on both sides of the mounting bracket 6 are brought into contact with the printed circuit board to stabilize the fixation.

However, in the above configuration, the end surface of the bent piece 7 of the mounting bracket 6, which is the contact surface with the printed circuit board, is small, and
The distance between the bent pieces 7 on both sides is small, as shown in FIG. 1B, and the center of gravity of the entire transformer part is placed on it, making it extremely unstable to fix the transformer.

In addition, since the bending piece 7 has a width of about 1 wIt and has a sharp edge, there is a risk of damaging the copper foil on the board in a double-sided board, which causes problems in terms of insulation voltage between the flyback transformer and other electrical components. It was something that happened.

Next, FIG. 2 shows an improved fixing structure of the flyback transformer shown in FIG. 1, in which a mounting tool 8 made of a plate material larger in shape than the metal fitting is used instead of the mounting metal fitting.

However, in this case, increasing the cost,
In addition, for stable fixation, it is necessary to increase the contact area of the fixture 8 with the board, which results in a larger shape, and depending on the layout of the board, the transformer part may not be able to be mounted or may come into contact with other elements. This was extremely inconvenient.

The present invention relates to a flyback transformer aimed at eliminating the above-mentioned drawbacks, and in particular, a hollow cylindrical leg is formed integrally with the bobbin at one end of the high-pressure bobbin to stably attach the flyback transformer to the board. This relates to a flyback transformer made up of

Hereinafter, one embodiment of the present invention will be described based on the drawings.

3 and 4 show the flyback transformer of the present invention, in which reference numeral 11 denotes a pair of U-shaped cores, on which a low-voltage coil 12 is wound around a low-voltage bobbin 13. The high voltage coil 14 wound around the high voltage coil 14 is mounted on the high voltage bobbin 15, and the low voltage bobbin 13 and the high voltage bobbin 15 are mounted in a state where they are integrally coupled.

The low-voltage bobbin 13 includes a cylindrical portion 16 into which the core 11 is inserted and a low-voltage coil 12 wound around the outer periphery, and a plurality of coupling protrusions 17 formed at one end of the cylindrical portion 16 for coupling with the high-pressure bobbin 15. The terminal mounting portion 19 includes a collar portion 18 in which a flange portion 18 is formed, and a substantially fan-shaped terminal mounting portion 19 formed at the other end of the cylindrical portion 16 and divided into a plurality of pieces.
is planted and fixed.

The low voltage bobbin 13 around which the low voltage coil 12 is wound is housed and fixed within a leg portion 21 formed at one end of the high voltage bobbin 15 made of an insulating material such as a frill.

As shown in FIG. 5, the high pressure bobbin 15 has a core 11 inside.
The cylindrical part 22 has a cylindrical part 22 into which the high-voltage coil 14 is inserted and is wound flat on the outer periphery, and the wall part 25 of the other side 24 has an opening in one side 23 formed at one end of the cylindrical part 22. Part 2
A hollow cylindrical leg portion 21 having an inner diameter slightly larger than the outer diameter of the low pressure bobbin 13 is integrally formed with the end portion of the low pressure bobbin 13 . A plurality of coupling holes 26 are formed to couple with the
A notch 27 is formed on the leg 21 through which the core 11 is inserted.

In the flyback transformer having such a configuration, the low voltage coil 12 is wound around the low voltage bobbin 13 at a predetermined position, and the terminal 20
The low pressure bobbin 13 is stored in the leg portion 21 of the high pressure bobbin 15 with the predetermined connection made to the
The connecting protrusion 17 formed at 8 is connected to the leg 2 of the high pressure bobbin 15.
1 and is fixedly coupled to a coupling hole 26 formed in the wall portion 25 of 1,
The high voltage coil 14 is fitted and fixed to the cylindrical portion 22 of the high voltage bobbin 15.

Then, the high-voltage coil 14 is connected to the terminal 20 of the terminal attachment part 19 provided on the low-voltage bobbin 13, and the coil portion is injected and filled with an insulating/heat-resistant resin (not shown) such as epoxy resin. , to be molded.

FIG. 6 shows the flyback transformer of the present invention installed on a printed circuit board. When the terminal 20 is inserted into the terminal insertion hole of the printed circuit board and fixed, the high voltage bobbin 1
The end face of the opening of the cylindrical leg 21 of No. 5 abuts on the substrate and is fixed in a stable state.

In the above embodiment, the case where the high voltage coil is flat-wound is described, but if the high-voltage coil is section-wound, a plurality of coils are installed in the cylindrical part 30 instead of the high voltage bobbin 15, as shown in FIG. It is also possible to use a high-pressure bobbin 33 in which a cylindrical part (hollow cylindrical leg part) 32 is integrally formed at the end of a split bobbin on which a flange part 31 is disposed.

Further, the fixing of the low pressure bobbin 13 and the high pressure bobbin 15 is not limited to the method of fixing the low pressure bobbin 13 and the high pressure bobbin 15 by using the coupling protrusion 17 and the coupling hole 26 as shown in the embodiment. It is okay to do so.

As described above, according to the flyback transformer of the present invention,
Continuing from the end of the cylindrical part of the high-voltage bobbin, which has a cylindrical part on which the high-voltage coil is wound, is a hollow that covers the outer periphery of the terminal attachment part formed at the end of the low-voltage bobbin, on which the low-voltage coil is wound and installed. Since the cylindrical legs are integrally formed, when the flyback transformer is mounted on a printed circuit board, the ends of the cylindrical legs formed on the high-pressure bobbin will come into contact with the board, and the end of the cylindrical legs formed on the high-pressure bobbin will come into contact with the board. The contact shape is cylindrical and the contact area is extremely wide, allowing the flyback transformer to be fixed on the board in a stable position and electrically without tilting or wobbling. It is.

In addition, compared to the case of using a conventional fixing device, the legs are just large enough to cover the outer periphery of the terminal attachment part of the low-voltage bobbin, so they occupy less floor space on the board, and compared to the case of using a conventional fixing plate. It has the advantage that it can be made smaller than when using.

Furthermore, since the hollow cylindrical leg is integrally formed with the high-pressure bobbin, there is no need to use a separate fixture as in the prior art, thereby reducing costs and improving assembly workability.

[Brief explanation of the drawing]

Figure 1A is a front view of a conventional flyback transformer.
Figure B is a bottom view, Figure 2 is a front view of another conventional flyback transformer, Figure 3 is a perspective view showing an embodiment of the flyback transformer of the present invention, and Figure 4 is an exploded perspective view. , FIG. 5 is a side view of the high-pressure bobbin, FIG. 6 is a front view of the high-pressure bobbin mounted on a printed circuit board, and FIG. 7 is a perspective view of the high-pressure bobbin of another embodiment of the flyback transformer of the present invention. 13: Low pressure bobbin, 15: High pressure bobbin, 19: Terminal attachment part, 21: Leg part.

Claims (1)

[Scope of utility model registration request] Continuing with the end of the cylindrical part of a high-voltage bobbin having a cylindrical part around which a high-voltage coil is wound, the outer periphery of a terminal mounting part shaped at the end of the low-voltage bobbin around which a low-voltage coil is wound is attached. A flyback transformer characterized by an integrated hollow cylindrical leg.