JPH07335452A - Surface mount induction electromagnetic equipment - Google Patents

Abstract

PURPOSE:To miniaturize a surface mount transformer wherein a mounting terminal and a coil winding terminal are separately provided. CONSTITUTION:A mounting terminal 8 is buried in the state of retracting by the depth of a notch part 10 formed on a notch part 10 formed on a bobbin 6 so that the position in the protrusion end (B) direction of the packaging terminal 8 may be almost equalized with that of the coil winding terminal 12. Furthermore, the surface of the coil winding terminal and outside coil 2a is kept at a specific distance so as to secure the safety of insulation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to miniaturization of a surface mounting induction electromagnetic device such as a transformer in which a mounting terminal and a coil winding terminal are separately provided.

[0002]

2. Description of the Related Art Generally, a surface mounting transformer is composed of a bobbin around which a coil is wound and mounting terminals are embedded, and a core attached to the bobbin, and is mounted on, for example, a printed circuit board. This state is shown in FIG. The surface mounting transformer T1 has a mounting terminal 8 (for example, a protruding length of about 2 mm) embedded in the bobbin 6 at a bent portion 8b thereof.
Then, the soldered portion 8c at the tip is soldered to the pattern P of the printed board 1 and fixed to the printed board 1. The coil lead wire 5 is wound around and connected to the projecting portion 8a of the mounting terminal.

FIG. 5 shows a schematic block diagram of the transformer T1. FIG. 5B is a sectional view taken along line AA of FIG. This transformer T1 is shown in FIG.
Between the a and the core 4b, the outer coil 2a and the inner coil 2b are wound around the core 4a via the bobbin 6, and the input voltage is stepped up or stepped down.

However, in the case of a step-up transformer in which the voltage on the output side is higher than that on the input side, the number of turns of the coil on the output side increases, so the coil wire on the output side needs to be thin. In this case, the mounting terminal 8 is often subjected to stress due to vibration during handling of soldering work or product transportation, and the coil lead wire 5 wound around is easily broken.

Therefore, conventionally, as shown in FIG. 5A, in the bobbin 6b on the output side, in addition to the mounting terminal 8, the coil winding terminal 12 (for example, a protruding length of about 1 m) is provided.
m) is provided, the coil lead wire 5 is wound around the coil winding terminal 12, and the rear end is connected in the bobbin 6b. The coil lead wire 5 was prevented from being broken by applying no stress. In addition, in FIG. 5, the bobbin 6 is integrally formed with 6a, 6b, and 6c. In FIG. 5A, the coil lead wire 5 on the input side is formed.
Is connected to the outer coil 2a on the front surface side of the transformer T1, and the coil lead wire 5 on the output side is connected to the inner coil 2b on the rear surface side.

[0006]

However, in the conventional transformer, as shown in FIG. 5A, the protruding length of the mounting terminal 8 is the length of the soldered portion 8c for mounting on the printed circuit board 1. As a result (see FIG. 4), the coil winding terminal 12 needs to be longer than the coil winding terminal 12 (about 1 mm), so that the size of the transformer T1 in the B direction becomes large.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to downsize a surface-mounting induction magnet provided with a mounting terminal and a coil winding terminal separately.

[0008]

In order to achieve the above object, an inner coil and an outer coil are wound around a surface mounting induction ceramic of the present invention, and a mounting terminal and a coil winding terminal are embedded. A bobbin and a core mounted on the bobbin, wherein the bobbin is provided with a notch, and the mounting terminal is embedded in a state of protruding outward from the notch. Therefore, the protruding end of the mounting terminal and the protruding end of the coil winding terminal from the bobbin are set to have substantially the same position in the protruding direction.

[0009]

According to the surface-mounting induction magnet of the present invention, the mounting terminal is embedded by being pulled in by the depth of the notch formed in the bobbin, and the position of the projecting end in the projecting direction is the coil winding terminal. Since it is almost the same as the projecting end of, the surface-mounting induction ceramic can be downsized, and the creepage between the coil winding terminal and the outer coil can be maintained at a predetermined distance to ensure insulation safety. Have secured.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a surface-mounting induction electromagnetic device (transformer) according to an embodiment of the present invention. Figure 1 (b)
Shows a sectional view taken along line AA of FIG. This transformer T
1A, a bobbin 6 in which the coil 2 is wound and a mounting terminal 8 is embedded, and a core 4 attached to the bobbin 6 are provided. In FIG. 1B, the outer coil 2a and the inner coil 2b are wound around the core 4a via the bobbin 6 between the core 4a and the core 4b. In this example, input is made. Boost the voltage.

Since the voltage on the output side bobbin 6b to be boosted is higher than that on the input side, the mounting terminal 8 for mounting the transformer T on the printed circuit board 1 (projection length of about 2 mm)
And a coil winding terminal 12 (projecting length of about 1 mm) for winding the coil lead wire 5 are separately embedded. The coil lead wire 5 is connected to the inner coil 2b on the back surface side of the transformer T.

Here, the mounting terminal 8 of the transformer T
Are embedded in the notch 10 formed in the bobbin 6b.

FIG. 2 shows a schematic perspective view of the bobbin 6b. The mounting terminal 8 embedded in the notch recess 10 of the bobbin 6b includes a protruding portion 8a, a bent portion 8b, and a soldered portion 8
c, the terminal 8 is bent at the bent portion 8b, the soldered portion 8c at the tip is soldered 3 to the pattern P of the printed circuit board 1, and the transformer T is fixed to the printed circuit board 1. The mounting terminal 8 and the coil winding terminal 12 are connected to each other at the rear end of the bobbin 6, and the coil winding wire 5 is wound around the coil winding terminal 12. Further, since the voltage is low and it is not necessary to make the coil lead wire 5 thin on the input side bobbin 6a, only the mounting terminal 8 is embedded, and the coil lead wire 5 is wound around the mounting terminal 8. This coil lead wire 5 is
The front side of the transformer T is connected to the outer coil 2a (see FIG. 1).

As shown in this figure, the mounting terminal 8 is a bobbin 6
Since it is embedded in the notch 10 formed in b, it is drawn into the bobbin 6b by the depth (about 1 mm) of the notch 10. Therefore, as shown in FIG. 1, the protruding end of the mounting terminal 8 and the protruding end of the coil winding terminal 12 from the bobbin 6b have substantially the same position in the protruding (B) direction (about 1 m).
m), the length of the transformer T in the B direction is shortened and the transformer T is downsized. In addition, in the bobbin 6b in which the coil winding terminal 12 is embedded, a cutout portion is not provided, and the coil winding terminal 1 is not provided.
The creeping surface between the outer coil 2 and the outer coil 2a is maintained at a predetermined distance to ensure insulation safety. Thus, the printed circuit board 1
The transformer T can be fixed close to the pattern P, and the storage space of the transformer T on the printed circuit board 1 can be reduced.

Also, as shown in FIG. 3, in a transformer in which a large number of mounting terminals 8 and coil winding terminals 12 are alternately arranged, each mounting terminal 8 is formed in the bobbin 6, and the cutout portion 10 is formed. It may be embedded in.

In this embodiment, a transformer is used as the induction magnet, but a choke or a reactor may be used.

[0017]

As described above, according to the present invention, the position of the projecting end of the mounting terminal in the projecting direction can be made substantially the same as that of the coil winding terminal, and the coil winding terminal is provided. The creepage between the outer coil and the outer coil is maintained at a predetermined distance to ensure insulation safety. As a result, it is possible to reduce the size of the surface mounting induction electromagnetic device (transformer) in which the mounting terminal and the coil winding terminal are separately provided.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a surface mounting induction electromagnetic device (transformer) according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing the surface-mounting induction magnet.

FIG. 3 is a configuration diagram when a plurality of terminals are arranged.

FIG. 4 is a view showing a mounting state of a surface mounting transformer.

FIG. 5 is a schematic configuration diagram showing a conventional surface mounting transformer.

[Explanation of symbols]

2a ... outer coil, 2b ... inner coil, 4 (4a, 4
b) ... core, 5 ... coil lead wire, 6 (6a, 6b, 6
c) ... bobbin, 8 ... mounting terminal, 10 ... notch, 12 ...
Terminal for coil winding.

Claims (1)

[Claims] 1. A surface-mounting induction porcelain comprising a bobbin around which an inner coil and an outer coil are wound, and in which a mounting terminal and a coil winding terminal are embedded, and a core attached to the bobbin. A notch is formed in the bobbin, the mounting terminal is embedded in a state of protruding outward from the notch, and a protruding end of the mounting terminal and a protruding end of the coil winding terminal from the bobbin are embedded. Is a surface-mounting induction magnet whose positions in the protruding direction are set to be almost the same.