JP2000021655A - Surface mount coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an inexpensive coil component having stabilized quality with high workability by fixing a coil to a central magnetic leg, leading out the lead end part along a groove, securing a claw part in a recess and fitting a positioning protrusion in a positioning recess. SOLUTION: Coils 3, 3a are fixed to the central magnetic leg 6 of a recessed core 20 and the lead ends 4, 4a of the coil are led out from a lead out groove 17 made in the side wall 7. Subsequently, the coil are secured to touch the lead out grooves 17 in the opposite outer side faces of the recessed core 20 and the outer bottom face 8. Thereafter, a claw part 10 formed at the forward end of the lead end part 4, 4a is clamped in a recess 9. Finally, a plate core 5 is applied to the bonding face at the open end of the recessed core 20 and secured in place. Alternatively, a positioning protrusion 5a provided on the plate core 5 may be press fitted in a positioning recess 5b made in the recessed core 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface mount type coil component, and more particularly to a surface mount type choke coil mounted on an electronic circuit board.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 4 (a), a surface mount type coil component of this type has a toroidal coil 13 wound around a toroidal core of a closed magnetic circuit and a plurality of metal terminals 14 embedded therein. It was housed inside the planted resin case 12, the lead wire 16 was wrapped around the terminal 14, and connected by soldering or welding. Further, as shown in FIG. 4B, a resin 15 or the like is injected into the resin case 12 to fix the coil 13.

[0005] In another example, FIGS.
As shown in (b), the plate-shaped core 19 and the insertion hole 23 of the lead terminal of the two coils 24 and 24a concentrically wound.
Are provided at four locations on the bottom surface, and a concave core 18 on which an electrode 21 is printed so that the outer side surface and the insertion hole 23 are connected to each other. Attached to the leg 6 and the coils 24, 24
a into the insertion hole 23, and
2 and finally the plate-shaped core 19 was joined to the concave core 18.

[0004]

However, conventional surface mount type coil parts require operations such as soldering and welding.
There was a problem that workability was poor.

[0005] In the case of a toroidal core, the thicker the winding, the more difficult it is to work on the terminals.

On the other hand, in the case of the plate core and the concave core, since the material is ferrite, warpage, burrs, and the like are apt to occur, and in order to obtain desired characteristics, the gap between the cores is reduced. This necessitates polishing work for the core joint surface.

In addition, since it is not possible to provide a projection for positioning for preventing displacement at the time of joining the plate-shaped core and the concave core, bonding and positioning operations are required.

Further, since it is necessary to cut the coil lead wire within the range of the bottom wall thickness of the concave core (t = about 0.8 mm in the example of FIG. 5), workability is extremely poor. The quality was not stable. For these reasons, there has been a problem that the resulting product is expensive.

An object of the present invention is to provide an inexpensive surface-mounted coil component which solves the above-mentioned problems, has good workability, is stable in quality, and has good quality.

[0010]

According to the present invention, there is provided a surface-mount type coil component comprising two coils which are wound concentrically and lead out from a plate-like lead end having a claw, and a plate-like having a positioning projection. A core, a bottomed box shape, a positioning recess on a fitting surface of the plate-shaped core, a center magnetic leg on an inner bottom surface, and a lead groove of the lead end on both outer side surfaces of opposed side walls, A concave core having a concave portion for fixing the claw portion at the tip of the lead end on the outer bottom surface, and a closed magnetic path core molded from a material obtained by mixing a molding resin and a magnetic powder such as ferrite;
The coil is mounted on the center magnetic leg, the lead end is led out along the lead-out groove, and attached as a surface mount terminal so as to be in contact with the external side surface and the bottom surface, and the claw portion is fixed to the concave portion. The plate core and the concave core are fitted by the positioning projection and the concave portion.

That is, the present invention relates to a plate-like lead end which is wound concentrically and has a claw portion, a closed magnetic path core comprising a plate-like core formed by mixing a molding resin and magnetic powder and a concave core. It consists of two coils whose parts have been led out.
Providing a positioning projection to be fitted with the concave core, the concave core, a positioning concave portion on a fitting surface with the plate-shaped core, a center magnetic leg on an internal bottom surface, a concave portion on an external bottom surface, and an external side surface. Providing a lead groove at the lead end, mounting the coil on the center magnetic leg, leading the lead end along the lead groove, fixing the claw in the recess, and positioning the coil. It is a surface mount type coil component in which a projection and the positioning recess are fitted.

[0012]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view of a surface-mount type common mode choke coil according to the present invention. FIG. 1 (a) is an exploded perspective view, and FIG. 1 (b) is a partially enlarged view of the concave core near the lead-out groove. FIG. 1C is a perspective view showing the external appearance of the concave core as viewed from below. FIG. 2 is an external perspective view of a coil used in the surface mount common mode choke coil of the present invention. FIG. 3 is an external perspective view showing a state in which the surface mount type common mode choke coil of the present invention is viewed from below.

As shown in FIG. 1, a surface mount type common mode choke coil 1 according to the present invention has closed magnetic circuit cores 2 and 2 each having a plate-shaped core 5 serving as a lid and a concave core 20 having a bottomed box shape. It consists of three coils 3, 3a. The plate-shaped core and the concave core are made of a material obtained by mixing magnetic powder such as ferrite and a molding resin. The plate-shaped core 5 is provided with four positioning projections 5a. The concave core 20 has a center magnetic leg 6 substantially at the center of the inner bottom surface, four recesses 9 for locking the ends of the lead ends 4 and 4a on the outer bottom surface 8, and a lead on the outer side surface of the side wall 7. A lead-out groove 17 at the ends 4, 4a is provided, and a positioning recess 5b is also provided.

As shown in FIG. 2, the coils 3, 3a are formed by concentrically winding two copper wires having a circular cross section, and providing lead ends 4, 4a at the lead terminals of these coils. . The lead ends 4, 4a of the coils 3, 3a are formed into a plate shape by rolling. The lead end may be stripped of the insulating film of the copper wire before rolling, rolled, and the portion may be plated with solder or another conductive metal.

The surface mount type common mode choke coil of the present invention having such a configuration is assembled as follows. As shown in FIG. 1, first, the coils 3 and 3b are mounted on the center magnetic leg 6 of the concave core 20 and the lead ends 4 and 4 of the coil are mounted.
4a is pulled out from the outlet groove 17 of the side wall 7.

Next, the lead ends 4 and 4a are formed with a mold jig so as to be in close contact with the outer periphery of the concave core, that is, the lead grooves 1 on both outer side surfaces of the concave core 20.
7 and further fixed so as to be in contact with the outer bottom surface 8. Next, as shown in FIG. 3, the claw portions 10 formed at the tips of the lead ends 4 and 4 a are engaged with the concave portions 9. As a result, the lead ends become surface-mount terminals.

Finally, an adhesive is applied to the joint surface at the open end of the concave core 20, and the plate core 5 is covered and fixed. In addition,
The positioning projections 5a provided on the plate-shaped core 5 and the positioning recesses 5b provided on the concave core 20 may be molded and fixed so as to be press-fitted.

In the surface-mount type common mode choke coil of the present invention, a portion to be connected by soldering or the like is eliminated without using a toroidal core as in the conventional case, and the core is made of a resin molded product. Since the positioning projection and the concave portion are provided, the workability is remarkably improved.
Further, in the surface-mount type common mode choke coil of the present invention, the defect rate has been improved from 5% of the prior art to 0.1%.

[0020]

As described above, according to the present invention, it is possible to provide an inexpensive surface-mounted coil component having good workability, stable quality, and low cost.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a surface-mount type common mode choke coil of the present invention. FIG. 1A is an exploded perspective view. FIG. 1 (b)
FIG. 4 is a partially enlarged perspective view of the vicinity of a lead-out groove of a concave core. FIG.
(C) is an external appearance perspective view which shows the state which looked at the concave core from the lower surface.

FIG. 2 is an external perspective view of a coil used in a surface-mount type common mode choke coil of the present invention.

FIG. 3 is an external perspective view showing the surface mounted common mode choke coil of the present invention as viewed from below.

FIG. 4 is an explanatory view of a conventional surface mount type coil component. FIG.
(A) is an exploded perspective view. FIG. 4B is an external perspective view.

FIG. 5 is an explanatory view of a conventional surface mount type coil component. FIG.
(A) is an exploded perspective view. FIG. 5B is a partially enlarged cross-sectional view near the insertion hole of the concave core.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface mount type common mode choke coil 2 Closed magnetic circuit core 3, 3a Coil 4, 4a (of the present invention) Lead end 5 Plate-like core (of the present invention) 5a Positioning projection 5b Positioning recess 6 Center magnetic leg 7 Side wall Reference Signs List 8 outer bottom surface 9 concave portion 10 claw portion 12 resin case 13 (toroidal) coil 14 terminal 15 resin 16 lead wire 17 lead-out groove 18 (conventional) concave core 19 (conventional) plate-shaped core 20 (conventional) concave core 21 Electrode 22 Solder 23 Insertion hole 24, 24a (conventional) coil

Claims (1)

[Claims] 1. A closed magnetic circuit core composed of a plate-shaped core and a concave core formed by mixing and molding a molding resin and magnetic powder, and a plate-shaped lead end having a claw portion and being wound concentrically. The plate-shaped core is provided with positioning protrusions to be fitted to the concave core, the concave core has a positioning recess at a fitting surface with the plate-shaped core, and an internal bottom surface. A center magnetic leg, a concave portion on the outer bottom surface, and a lead groove for the lead end provided on the outer side surface, the coil is mounted on the center magnetic leg, and the lead end is led out along the lead groove. A surface-mounted coil component, wherein the claw portion is fixed to the concave portion, and the positioning protrusion and the positioning concave portion are fitted.