JPH10223450A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coil component of a mounting type using a core by an electrically conductive material by a method wherein a coil member is installed in the interior of an electrically conductive core member and both end parts of a flat-type wire or a wire material which is derived to the side of the bottom face of the core member are fixed by a sheet member. SOLUTION: A coil 102 is formed such that a thin sheetlike flat-type wire 103 is wound in a spiral shape, one end part 103a and the other end part 103b of the flat-type wire 103 are bent to the side of the bottom face 104 of a core 105b so as to be fixed at a prescribed position. A core 105a and a core 105b are formed of a ferrite material, their cross section is U-shaped, and core parts which protrude to be cylindrical are formed in their central parts. In addition, in the cores 105a, 105b as one pair, a heat-resistant tape 107 having an adhesive face is wound on their outer circumferential faces together with a first insulating sheet 106a so as to make one round or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a coil component that can be used, for example, as a surface mount component.

[0002]

2. Description of the Related Art Heretofore, there have been known coil components in which a core (magnetic core) is formed using a core material having no electric conductivity and which can be surface-mounted on a printed circuit board. I have.

That is, in this case, a coil is housed inside the core, and furthermore, each of the lead frames, in which both ends of the coil at the beginning and end of winding are electrically connected separately, Attached to the bottom of the core. The method of attaching the lead frame is to caulk each lead frame directly below the core. That is, in this caulking structure, both ends of the coil are not short-circuited even if the electrical insulation structure is not taken. As described above, this is because the core itself does not have electric conductivity.

In each lead frame crimped at the lower portion of the core, a terminal to be connected to the printed circuit board is disposed on the bottom surface of the core.

[0005]

However, the core of such a conventional coil component has been limited to a core material having no electrical conductivity. Therefore, there has been a demand for a coil component in which a core is formed of a core material having electrical conductivity, as described above, of a surface-mount type coil component.

An object of the present invention is to provide a coil component of a surface mount type using a core made of an electrically conductive material in consideration of such problems of a conventional coil component.

[0007]

According to a first aspect of the present invention, there is provided a coil member in which a thin rectangular wire or a wire having both ends substantially in a flat shape is formed into a coil shape, and the coil member is provided inside the coil member. Provided, a core member having electrical conductivity, and both ends of the rectangular wire or both ends of the wire drawn out from the inside to the bottom side of the core member are fixed to the bottom surface. It is a coil component provided with an electrically insulating and adhesive sheet member provided.

According to a second aspect of the present invention, the core member is a coil component formed of a ferrite material.

According to a third aspect of the present invention, the sheet member includes an insulating sheet having electrical insulation provided on a bottom surface of the core member, and a film sheet for fixing the insulating sheet to the bottom surface. And an adhesive sheet fixing the film sheet and the both ends.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a noise filter 101 which is an embodiment of a coil component according to the present invention.
FIG. 2 is a cross-sectional view taken along the line YY in FIG. 1, and the configuration of the present embodiment will be described with reference to FIG.

As shown in FIG. 1, the coil 102 is a coil formed by winding a thin rectangular wire 103 into a spiral shape. That is, it is wound so that the width direction of the thin rectangular wire 103 is orthogonal to the axial direction of the spiral shape. The flat wire 103 is coated with an insulating film.

One end 103a and the other end 103b of the rectangular wire 103 are terminals that are bent toward the bottom surface 104 of a core (magnetic core) 105b, which will be described later, and are fixed at predetermined positions. On the surfaces of these terminals, an insulating film is peeled off and a solder film is formed. The configuration for fixing the terminals will be further described later.

The cores 105a and 105b are formed of a ferrite material, have a U-shaped cross section, and have core portions 105c and 105d protruding in a columnar shape at the center. Each of the cores 105a and 105b has a coil 102 provided therein (see FIG. 3). That is,
The coil 102 is sandwiched between a pair of cores 105a and 105b of the same shape from above and below.
c and d are held in a state of being inserted into a space formed on the central axis of the coil 102. A pair of cores 105a,
b is wound one or more times around the outer peripheral surface thereof by a heat-resistant tape 107 having an adhesive surface together with a first insulating sheet 106a described later. FIG. 3 is a perspective view of a pair of cores 105a and 105b disposed on the upper and lower surfaces of the coil 102.

The first insulating sheet 106a includes a core 105b.
Is a paper for electrical insulation disposed on the bottom surface of the core, and has a rectangular outer shape and a size slightly larger than the bottom shape of the core as shown in FIG.

Further, the second insulating sheet 106b is a coil 1
02 is a paper for electrical insulation disposed between the upper surface of the core 02 and the core 105a and between the lower surface of the coil 102 and the core 105b, has a rectangular outer shape, and has core portions 105c and 105d.
Are respectively formed in the center.

Next, including the fixing of both ends described above,
The configuration on the bottom surface side of the core 105b will be further described with reference to FIGS.

As shown in FIG. 2, the pressure-sensitive adhesive sheet 108 is made of a heat-resistant tape 107 applied to the bottom surface 104 of the core 105b.
It is a sheet having high heat resistance having adhesive properties on both surfaces thereof. Further, both ends 103a and 103b of the flat wire 103 are adhered to the lower surface of the adhesive sheet 108 (the lower surface of the adhesive sheet 108 on the paper in FIG. 2). That is, both ends 103a,
103 b is fixed to the surface of the heat-resistant tape 107 by the adhesiveness of the adhesive sheet 108. Heat resistant tape 1
07 is fixed to the cores 105a and 105b by bonding as described above. Thus, even if the flat wire 103 is formed in a thin plate shape or without using a plate-shaped board component, both ends 103a and 103b of the flat wire 103
It can be reliably positioned and fixed to the lower surface 104 of b. In addition, the sheet member of the present invention includes the first insulating sheet 106a, the heat-resistant tape 107, and the adhesive sheet 108. In FIG. 2 and FIG. 4, which will be described later, the thicknesses of the first insulating sheet 106a, the second insulating sheet 106b, the heat-resistant tape 107, the adhesive sheet 108, and the like are exaggerated from the actual values. Relative relationships with part size are ignored.

Next, the case where the noise filter 101 of the present embodiment thus configured is mounted on a printed circuit board will be described with reference to FIG.

FIG. 4 is a cross-sectional view showing a state where the noise filter 101 is arranged on the printed circuit board 401.

That is, as shown in FIG.
01 is disposed at a predetermined position on the printed circuit board 401, and the surface of each end 103a, 103b and the pattern 4
02 is electrically connected to the surface of the device by solder (not shown). Thereby, the noise filter 101
Is completed on the surface of the printed circuit board 401.

As described above, according to the present embodiment, it is possible to provide a noise filter having a core formed of an electrically conductive core material, and as described above, a surface mount type noise filter. .

In this embodiment, the core 105b and each of the end portions 103a, 103b are used without using a plate-like substrate part.
In order to electrically insulate the core 105b, an insulating sheet 106a having an extremely small thickness was used, and for fixing the ends 103a and 103b to the core 105b, a heat-resistant tape 107 and an adhesive sheet 108 each having an extremely thin thickness were used. Thus, the height of the entire noise filter component 101 can be reduced.

The coil member according to the present invention is not limited to the case where the thin rectangular wire of the above embodiment is formed into a coil shape. For example, a wire having substantially flat ends at both ends is formed into a coil shape. May be adopted. Processing of the coil wire in this case will be described below as another embodiment of the present invention with reference to FIG. Here, differences from the above-described embodiment will be mainly described, and other configurations are the same as those in the above-described embodiment.

FIGS. 5 (a) and 5 (b) show the end of the wire 501 after the end of the wire 501 used in the present embodiment has been subjected to a pressing process to make both ends substantially flat. It is the top view and front view which show a shape.

That is, at the both end portions of the coil which are left with a predetermined length in a circular cross section, the tip portions (in FIG. 5 (b),
5 (a) and 5 (a), except for the part to be subjected to the press working (corresponding to the part marked with B in FIG. 5) connected thereto, except for the part marked with A. As shown in (b), pressure is applied so as to form a flat plate having a thickness t and width W.

Thereafter, a solder film is formed on the tip portion A and the processed portion B. Further, at a position P shown in the figure,
The wire 501 is cut, and the tip A is removed.

Then, at the positions Q1 and Q2 shown in the figure, the wire 501 is bent substantially at a right angle. At this time, the bent tip portion is the core 10 as described in FIG.
5b is bent so as to come to the surface of the adhesive sheet 108 fixed to the lower surface side of 5b. Thereafter, both ends of the flat plate shape are pressed against the surface of the pressure-sensitive adhesive sheet 108 to be adhered and fixed. In the above configuration, the same effect as in the above embodiment is exerted.

Further, the core member of the present invention is not limited to the core formed of the ferrite material of the above embodiment, and may be formed of, for example, another material having electrical conductivity.

In the above embodiment, the sheet member of the present invention includes an insulating sheet having electrical insulation provided on the bottom surface of the core member (corresponding to the first insulating sheet 106a);
It is composed of a film sheet (corresponding to the heat-resistant tape 107) for fixing the insulating sheet to the bottom surface, and an adhesive sheet (corresponding to the adhesive sheet 108) fixing the film sheet and the both ends. However, the present invention is not limited to this. For example, an adhesive sheet having adhesiveness on both sides may have a configuration having electric insulation. In this case, the first insulating sheet 106a may not be provided.

[0031]

As is apparent from the above description,
The present invention has an advantage that it is possible to provide a surface mount type coil component using a core made of an electrically conductive material.

[Brief description of the drawings]

FIG. 1 is a perspective view of a noise filter according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the noise filter according to the embodiment.

FIG. 3 is a perspective view of a pair of cores used in the noise filter according to the embodiment.

FIG. 4 is a sectional view showing a state in which the noise filter according to the present embodiment is arranged on a printed circuit board;

FIG. 5A is an enlarged plan view of a leading end portion of a coil wire used in a noise filter according to another embodiment of the present invention in a processing stage. FIG. 5B is an enlarged plan view of the coil wire of the embodiment. Enlarged front view of the tip in the processing stage

[Explanation of symbols]

 Reference Signs List 101 noise filter 102 coil 103 rectangular wire 103a one end 103b other end 104 bottom surface 105a, b core 105c, d core portion 106a first insulating sheet 106b second insulating sheet 107 heat resistant tape 401 printed circuit board 402 pattern

Claims (3)

[Claims] 1. A coil member in which a thin rectangular wire or a wire having both ends substantially in a flat shape is formed into a coil shape; and a core member having electric conductivity, wherein the coil member is provided inside; An electrically insulating and adhesive sheet disposed on the bottom surface, fixing both ends of the flat wire drawn out from the inside toward the bottom surface side of the core member or both ends of the wire material to the bottom surface. And a member. 2. The coil component according to claim 1, wherein said core member is formed of a ferrite material. 3. The sheet member comprises: an insulating sheet having electrical insulation provided on a bottom surface of the core member; a film sheet for fixing the insulating sheet to the bottom surface; The coil component according to claim 1, comprising an adhesive sheet fixing both ends.