JPS6011613Y2 - Low pressure bobbin for flyback transformer - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a low-pressure bobbin for a flyback transformer used in a television receiver.

As shown in Figs. 1, 2, 3, and 4, a mold type flyback transformer in which the coil portion is molded with an insulating material has a high voltage coil 3 placed on the outside of a low voltage bobbin 2 on which a low voltage coil 1 is wound. The winding ends 5 of the coils 1 and 3 are connected to the pin terminals 8 on the plurality of terminal attachment parts 7 formed on the base end 6 of the low voltage bobbin 2 and soldered. This is then stored inside the case 9, and the insulating material 11 is cooled.

The ferrite core 10 is filled into the low pressure bobbin 2.
This insulating material 11 is fitted into the center hole of
When filling, as shown in Figure 2, when inserting the pin terminal 8 directly into the board and installing the flyback transformer on the board, take care not to cause a short circuit accident, and wrap it around the pin terminal 8 with solder. The insulating material surface 13 must be positioned above the connection solder portion 12 to which the end portion 5 is connected.

However, in this case, a large amount of insulating material 11 is required to completely mold the connecting solder portion 12, and this amount cannot be ignored in this type of electrical component that is produced in large quantities. If the connection solder part 12 reaches a part close to the center of the pin terminal 8 due to variations in the process of connecting the winding end 5 to the pin terminal 8, more insulating material 11 is required, and in some cases, the case head Face 14
There is a risk that the insulation material 11 will leak to the outside.
During the pouring work, it was necessary to control the height of the insulating material surface 13, resulting in significantly poor workability.

On the other hand, a non-molded case type flyback transformer is constructed from the above-mentioned molded case type flyback transformer except for the case 9 by using a molding die. Convenience,
The high-pressure bobbin, core, and molding material are omitted.

), when attaching the flyback transformer to the board by inserting the pin terminal 8 into the insertion hole 16 of the board 15, since the connection solder part 12 is formed at the base of the pin terminal 8, the terminal mounting part 7 cannot be mounted in close contact with the board 15.

This invention was made to eliminate the above-mentioned drawbacks, and examples thereof will be described below with reference to the drawings.

Figures 6 and 7 show the low-pressure bobbin 21. In the figures, 22 is a cylindrical coil winding part in which a number of protrusions 23 are arranged along the circumferential surface. The portion 22 has a low voltage coil wound thereon, and a cylindrical high voltage bobbin having a high voltage coil wound on the outside thereof is mounted in contact with the protrusion portion 23 .

24 is a central hole in which a ferrite core is inserted, which is drilled along the central axis from the base end 25 to the tip 26 of the coil winding section 22; 27 is a center hole in which the ferrite core is fitted; A pin terminal 28 is integrally formed in the vertical direction from the coil winding part 22 and extends radially from the coil winding part 22 to the base end part 25 of the coil winding part 22 for positioning and fixing the ferrite core. The attachment portion 29 is a step recess formed at the tip of the outer surface 28a of the pin terminal attachment portion 28, and the reference numeral 30 is a pin terminal embedded in the step recess 29 to connect the winding end of the coil.

The low-voltage bobbin 21 has a cylindrical high-voltage bobbin in which a low-voltage coil is wound around a winding part 22 and a high-voltage coil is wound on the outside of the coil-winding part 22. The winding end 31 of the coil is connected to the pin terminal 30. To explain this relationship with reference to FIG. 8, first, as shown in FIG.
The terminal is pulled out to the pin terminal 30 installed upright in the pin terminal mounting portion 28 of the terminal, and is tied to the approximately central portion of the pin terminal 30.

Next, as shown in FIG. 8, the barbed portion 32 of the winding end 31 is pushed down to the base of the pin terminal 30 and housed in the stepped recess 29.

Then, when the excess winding at the tip of the curly part 32 is cut off and soldered as shown in FIG. It is located inside, that is, at a height below the outer surface 28a.

FIG. 9 shows a mold type flyback transformer in which the flyback transformer section configured as described above is housed inside the case 34 and molded with an insulating material 35, and the connecting solder section 33 of the pin terminal 30 is completely removed. Since it is molded, in conventional low-voltage bobbins, it was necessary for the insulating material surface 35a to be located above the outer surface 28a of the pin terminal attachment part 28, but this specialized low-voltage bobbin 21
If this is used, only surface A below the outer surface 28a of the pin terminal mounting portion 28 will be sufficient.

Furthermore, the connecting solder portion 33 is connected to the outer surface 2 of the pin terminal mounting portion 28.
Considering that there is no particular problem in terms of insertability and insulation of the board as long as it does not exceed 8a, there is no need to fill the insulating material 35 up to side A, and it is not necessary to completely mold the coil part B.
It will also be a good thing.

FIG. 10 shows a non-molded case type flyback transformer that does not use a molded case. When this flyback transformer is installed on a printed circuit board 36, the connecting solder portion 33 is connected to the stepped recessed portion of the pin terminal mounting portion 28.
9. Outer surface 2 of pin terminal mounting portion 28 to be accommodated inside
8a and the board surface 36a of the printed circuit board 36, and only the pin terminal 30 is inserted into the insertion hole 37 of the printed circuit board 36, and the connecting solder part 33 is not inserted. There is no need to take measures such as locking, and the insertion hole 37 and pin terminal 30 are firmly fitted, and the flyback transformer is stably fixed.

Note that the low-voltage bobbin of this invention is not limited to the configuration of a high-voltage bobbin and a high-voltage coil, and can be combined with any high-voltage bobbin and high-voltage coil to form a flyback transformer.

As described above, if a flyback transformer is formed using the low-voltage bobbin of this invention, the connecting solder part will not be exposed beyond the outer surface of the pin terminal mounting part, so insertion ease when mounting the board is good, and the connection between the board and the board is good. The fixation becomes stronger, and the insulation of the connecting solder part also becomes better, improving electrical stability.

Furthermore, when used in a type of flyback transformer that is molded with insulating material, the amount of insulating material to be filled can be reduced compared to conventional methods, which can significantly reduce costs for flyback transformers that can be mass-produced. Not only that, but it can also be made smaller and lighter.

Furthermore, in a mold type flyback transformer, the connection solder part is housed in a stepped recess and is formed at a fixed position, making it easier to control the surface height of the insulating material filled into the case. Workability can be significantly improved compared to .

[Brief explanation of the drawing]

Figures 1 to 5 show conventional examples, where Figure 1 is a longitudinal sectional front view of a mold type flyback transformer formed using a conventional low-pressure bobbin, Figure 2 is an enlarged view of the same, and Figure 3 is an enlarged view of the same. The figure is a perspective view of a conventional low-pressure bobbin, Fig. 4 is an enlarged perspective view of a part of the low-pressure bobbin, and Fig. 5 is a state in which a board is attached to a non-molded case type flyback transformer formed using a conventional low-pressure bobbin. It is an explanatory diagram. Moreover, FIGS. 6 to 10 show examples of this invention, in which FIG. 6 is a perspective view of a low-pressure bobbin, FIG. 7 is an enlarged perspective view of a part of the low-pressure bobbin, and FIG. 8 a, by c. 9 is an explanatory diagram of the state in which the winding end of the coil is connected to the pin terminal, FIG. 9 is an enlarged cross-sectional view of a part of a mold type flyback transformer formed using the low-voltage bobbin of this invention, and FIG.
The figure is an explanatory view showing the mounting state of a board of a non-molded case type flyback transformer formed using the low-pressure bobbin of this invention. 21: Low pressure bobbin, 28: Pin terminal attachment part, 29: Step recess, 30: Pin terminal, 31: Winding end of coil, 33:
Connection solder part.

Claims (1)

[Scope of utility model registration request] In a low-voltage bobbin in which a plurality of pin terminal mounting parts each having a pin terminal arranged at the base end of the coil winding part are integrally formed, a stepped recess is formed in the pin terminal mounting part, and the pin terminal is arranged in the stepped recess. A low-voltage bobbin for a flyback transformer, characterized in that a connecting solder portion of a coil winding end connected to the pin terminal is housed in the stepped recess.