JP2814949B2 - Line filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line filter used on a power supply side of various electronic devices.

[0002]

2. Description of the Related Art A conventional line filter of this type includes a bobbin, a pair of windings wound around the outer periphery of the bobbin,
An input terminal provided on each input side of the pair of windings, an output terminal provided on each output side of the pair of windings,
A bobbin-shaped core having one side penetrated in a through-hole at the center axis of the bobbin.

[0003]

The problem with the above construction is that the opposite side facing the one side rotates around the outer periphery of the bobbin around one side through which the core penetrates the through hole portion of the bobbin. Therefore, the magnetic flux is easily affected by the leakage magnetic flux to other portions, or noise is likely to enter the core. SUMMARY OF THE INVENTION It is an object of the present invention to suppress the magnetic influence on other components due to the leakage magnetic flux from the core and to eliminate noise from entering the core.

[0004]

In order to achieve this object, the present invention provides a bobbin, a pair of windings wound around the outer periphery of the bobbin, and an input side of each of the pair of windings. An input terminal, an output terminal provided on each output side of the pair, and a square-shaped core having one side penetrated through a through hole in a center shaft portion of the bobbin, and the rotation of the core Rotation prevention means for preventing
The rotation preventing means is provided at an end of the through hole of the bobbin.
Cover for providing a concave portion in the portion and holding the core
And inserting the end of the cover into the recess,
A means for holding and fixing the core and preventing rotation of the core
Configuration.

[0005]

With the above arrangement, the end of the through hole of the bobbin is recessed.
And a cover for holding the core,
Insert the end of the bar into the recess, hold and fix the core,
Is provided, the opposite side of the core does not rotate on the outer periphery of the bobbin.
Due to leakage flux from the core Ru can be suppressed magnetic influence on other components.

[0006]

1 and 2, reference numeral 1 denotes a bobbin made of a synthetic resin, and a pair of windings 2 shown in FIG. The left side of the winding 2 in FIG. 4 is the input terminal 3, and the right side is the output terminal 4. Further, a through hole 5 is provided in the center axis portion of the bobbin 1, and one side 6 a of the core 6 having a square shape as shown in FIG. 2 penetrates the through hole 5. That is, the bobbin 1 is divided into two at the through hole 5 and is united with one side of the core 6 sandwiched in the through hole 5, and thereafter the winding 2 is wound.

Here, the bobbin 1 is divided into two parts. The bobbin 1 is divided into two semi-cylindrical bodies 1a as shown in FIG.
Is prepared, and one of them is turned halfway, and then the side where the through-hole 5 is formed is inwardly joined to be formed. The semi-cylindrical body 1a is located at the center of the through hole 5 of each semi-cylindrical body 1a
Since the concave portion 1b is provided in order to prevent a from bending in the shape of a letter F in FIG. 3, when two semi-cylindrical bodies 1a are united, they do not become stuck. A cylindrical body is formed.

Next, the core 6 is erected with the opposing side 6b opposing the side 6a disposed above the bobbin 1 as shown in FIG. 2, and in this state, the synthetic resin cover 7 is attached to the opposing side. 6b. The cover 7 has a U-shape, and both ends thereof are further bent inward, and this bent portion 7a is formed into a concave portion at both ends of the through hole 5 of the bobbin 1 (FIG. 3).
1c) is held and fixed in the state shown in FIG. 1, thereby protecting the core 6 and preventing rotation of the opposing side 6b. Also, make sure that noise does not enter the core 6.
It can also be suppressed.

The openings 7a provided at both ends corresponding to the opposite sides 6b of the cover 7 are for dissipating heat from the core 6, and the cover 7 is formed of synthetic resin by providing the openings 7a. In doing so, the resin easily flows and becomes easy to make.

[0010]

As described above, the present invention relates to a bobbin, a pair of windings wound around the outer periphery of the bobbin, an input terminal provided on each input side of the pair of windings, An output terminal provided on the output side of the bobbin, and a square-shaped core having one side penetrated through a through-hole in the center axis portion of the bobbin, covering opposite sides opposing one side of the core and both ends thereof The portion is provided with a U-shaped cover inserted into the through hole of the bobbin.

[0011] With the above configuration, the opposing sides of the core are covered with a U-shaped cover, and both ends of the cover are inserted into and fixed to the through holes of the bobbin. It does not rotate, so that it is possible to suppress the magnetic influence on the other parts due to the leakage magnetic flux from the core, and to suppress the intrusion of noise into the core.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of the present invention.

FIG. 2 is an exploded perspective view of FIG. 1;

FIG. 3 is a perspective view showing a half of the bobbin of FIG. 1;

FIG. 4 is an electric circuit diagram of FIG.

[Explanation of symbols]

 Reference Signs List 1 bobbin 2 winding 3 input terminal 4 output terminal 5 through hole 6 core 6a one side 6b opposite side 7 cover 7a opening

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroshi Tomita 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-6-290973 (JP, A) JP-A-8- 255721 (JP, A) Hikaru 7-18416 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) H01F 27/28-27/30

Claims (3)

(57) [Claims] 1. A bobbin, a pair of windings wound around the outer periphery of the bobbin, an input terminal provided on each input side of the pair of windings, and an output terminal provided on each output side of the pair of windings comprising terminal and, a central shaft portion hollow square shaped core one side was passed through the through hole of the bobbin, before
A rotation preventing means for preventing rotation of the core is provided.
The rotation preventing means has a concave at an end of the through hole of the bobbin.
And a cover for holding the core.
And inserting the end of the cover into the recess,
A line filter as a means for holding and fixing the core and preventing rotation of the core . 2. The line filter according to claim 1, wherein the bobbin is divided into two at the through-hole portion , and a concave portion is formed at the center of the through-hole portion of the half-cylindrical body divided into two. 3. The cover has an opposite side facing one side of the core.
With a U-shape with a portion covering the part, claims having an opening in a portion covering the opposite sides of the core of the cover
2. The line filter according to 1 .