JP3313138B2 - Balun for surface mounting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balun for surface mounting using a core such as a ferrite used for a distribution circuit, a mixing circuit, and the like of a high-frequency RF unit such as a UHF, VHF electronic tuner, and a BS tuner.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
As shown in FIG. 7 of the circuit diagram, four lead wires 3, 4, 5, and 6 were wound around the core 2 provided as shown in FIG. Then, the coating on the end drawn out of the through-hole 1 was removed, and the terminals 7, 8, 9, 10, 11 were used as various input / output terminals.

[0003]

The insertion balun constructed as described above is mounted on a printed circuit board 12 as shown in FIG. That is, the terminals 7 to 11 are connected to the printed circuit board 12.
And is connected to the land 14 by solder 15. However, in this case, as is apparent from FIG. 8, it is necessary to insert the terminals 7 to 11 into the through holes 13, and this has to be done manually, which is inferior in workability. Accordingly, the present invention provides a balun for surface mounting which can greatly simplify this mounting operation.

[0004]

In order to achieve the above object, the present invention has a through-hole, and the through-hole extends in the same direction as the through-hole.
Row, and the upper surface of the
And a square core having a flat portion formed on the lower surface ,
The core is provided with two or more lead wires penetrating through holes, and a position indication mark is provided on the lower surface, and all ends of the lead wires are drawn out of the through holes, and the coating is removed respectively. All the terminals are led out to the lower surface and bent on the position indicating mark.

[0005]

With the above construction, all the terminals are bent toward the position indication marks on the outer wall on the lower surface of the core, and are connected by directly abutting the lands on the printed circuit board.
It is possible to extremely simplify child the mounting work
Can be.

[0006]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 14 denotes a core made of ferrite, and two through holes 15 are arranged in a horizontal direction.
The upper and lower surfaces 16 and 17 have a square shape that is flat. In order to form the circuit configuration shown in FIG. 7 in these through holes 15, four lead wires 18, 19, 20,
21 are wound. The ends drawn out of the through holes 15 are stripped of the coating to become the terminals 7a to 11a. After the terminals 7a to 11a are drawn out of the through holes 15 as shown in FIG. hand,
It is bent to the lower surface 17 along the lead position display mark 22. The mounting is performed with the lower surface 17 of the core 14 facing the printed circuit board 23 as shown in FIG. That is, a land 24 is provided on the upper surface of the printed circuit board 23, and the terminals 7a to 11a are brought into contact with the land 24, and soldering is performed in this state.
What should be noted here is that the terminals 7a and 9a are bent only one, unlike the twisted plural terminals like the other terminals 8a, 10a and 11a. A gap 25 is provided between the core 14 and the lower surface 17 so that the attachment is properly performed. As shown in FIG. 3, it is also possible to form a lead positioning groove 26 on the lower surface 17 side of the core 14 in accordance with each terminal so that the terminals 7a to 11a of the lead wires can be reliably positioned.

(Embodiment 2) FIGS. 4 and 5 show another embodiment. In this embodiment, three lead wires 27, 28 and 29 are provided. The two terminals 30 and 31 are on the lower surface 17 side of the core 14, and the other two 32 and 33 are on the upper surface 1.
The terminal 34, which is bent to the side 6 and fitted from the two, has a through-hole 15
It is projected in the direction. As shown in FIG. 5, only the terminal 34 penetrates through the through hole 23a of the printed circuit board 23, is soldered to the land 23b on the lower surface, and the other terminals 30 to 33 are soldered to the land on the upper surface. . This requires a penetrating operation into the through hole 23a of the printed circuit board 23, but since only one penetrates, the operation can be easily performed.

[0009]

As described above , according to the present invention, all the terminals are bent toward the position indicating mark on the outer wall on the lower surface of the core, and the land of the printed circuit board is bent . Can be connected directly to the connection, greatly simplifying the mounting work
can do.

[Brief description of the drawings]

FIG. 1 is a perspective view of a surface mount balun according to a first embodiment of the present invention.

FIG. 2 is a side view showing a surface mounted balun according to the first embodiment of the present invention;

FIG. 3 is a perspective view of a surface mount balun having a terminal positioning groove added to the first embodiment of the present invention.

FIG. 4 is a perspective view of a surface mount balun according to a second embodiment of the present invention.

FIG. 5 is a sectional view of a balun for surface mounting according to a second embodiment of the present invention.

FIG. 6 is a perspective view of a conventional insertion balun.

FIG. 7 is a circuit diagram of a conventional insertion balun.

FIG. 8 is a side view of a conventional insertion balun.

[Explanation of symbols]

 7a terminal 8a terminal 9a terminal 10a terminal 11a terminal 14 core 15 through hole 16 upper surface 17 lower surface 18 lead wire 19 lead wire 20 lead wire 21 lead wire 22 lead position display mark 23 printed circuit board 24 land 25 gap 26 lead positioning groove

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hiroshi Nagai 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Akio Iwase 1006 Kadoma Kadoma, Kadoma City Osaka Prefecture (56) References Japanese Utility Model Showa 62-158804 (JP, U) Japanese Utility Model Showa 55-124819 (JP, U) Japanese Utility Model Showa 51-142141 (JP, U) Japanese Utility Model Showa 61-104514 (JP, U)

Claims (2)

(57) [Claims] 1. A through hole having a through hole,
Are provided in parallel with each other with the through hole interposed therebetween.
A rectangular core having a plane portion formed on a surface and a lower surface; and two or more lead wires penetrating through a through hole of the core; Pull out all the ends of the
Each of the terminals is obtained by removing the coating, and all of these terminals are led out to the lower surface and bent over the position indicating mark. 2. A through-hole having a through-hole,
Are provided in parallel with each other with the through hole interposed therebetween.
A rectangular core having a flat portion formed on a surface and a lower surface, and two or more lead wires penetrated through a through hole of the core, and a positioning groove is provided on the lower surface; All the ends are drawn out of the through holes, and the coatings are respectively removed to form terminals. All these terminals are led out to the lower surface and bent into the positioning grooves.