JP2748212B2 - Composite coil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil structure that can be used for an LC filter or the like, and more particularly to a composite coil in which a plurality of coils are integrated.

[0002]

2. Description of the Related Art In the field of portable electronic equipment, there is an increasing demand for miniaturization of LC filters and the like. A laminated chip type composite coil formed by alternately laminating and sintering conductors and magnetic materials by means such as printing is easy to miniaturize, and at present, a composite coil of about 3.5 mm square has been put into practical use. I have. However, while the stacked chip type can reduce the mounting area, it has disadvantages such as an increase in inductance variation and a decrease in Q. Although a wound type is advantageous for obtaining a coil having a small inductance variation and a large Q, it has been extremely difficult to reduce the size to the same size as a laminated chip type using a conventional drum type core.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a composite coil which can be remarkably miniaturized while using a winding type coil having a small inductance variation and a large Q.

[0004]

A composite coil according to the present invention has a plurality of cores made of a plate-like magnetic material having flanges at both ends of a winding shaft, the thickness of which is larger than the thickness of the winding shaft. A coil wound around the core winding of the core and connected to the electrode provided on the flange, and an external terminal connected and fixed to the electrode, so that the winding axes of adjacent cores intersect at right angles. In this case, a plurality of cores are stacked and fixed.

[0005]

FIG. 1 is a perspective view showing an embodiment of a composite coil according to the present invention, FIG. 2 is an exploded perspective view thereof, and FIG. 3 is a front sectional view. This composite coil comprises two flat coil elements 1,
2, spacers 30 made of an insulator, and external terminals 41 and 42 having different lengths. The cores 10 of the coil elements 1 and 2 are made of a non-conductive magnetic plate such as a Ni—Zn ferrite. As shown in FIG. 4, the core 10 is
13 has flanges 11 and 12 at both ends, the overall vertical dimension A and the horizontal dimension B are the same H shape when viewed from above, and the thickness of the flanges 11 and 12 is greater than the thickness of the winding shaft 13. Is made of a large plate-like magnetic material. In particular, as shown in FIG. 5, the core 10 of this embodiment has flanges 11 and 12 projecting to one side in the thickness direction, and one surface in the thickness direction is flat, and has a substantially U-shaped cross section. Also,
The core 10 is provided with a plurality of electrodes 14 in a depression formed from the upper surface (or lower surface) to the side surface of one flange 11 by printing and printing silver paste. When the core 10 is made of a conductive material such as a Mn-Zn-based ferrite, after providing an insulating layer on the surface of the core 10,
The electrode 14 may be formed thereon.

The coil 20 is wound around the winding shaft 13 of the core 10, and the terminal 21 of the coil 20 is connected to the electrode 14, whereby the flat coil elements 1 and 2 are formed. The concave portions 15 and 16 formed on the side surfaces of the flanges 11 and 12 are for holding the core 10 with a chuck when the coil 20 is wound around the winding shaft 13. Grooves 31 for passing external terminals 41 and 42 are provided on two side surfaces of the frame-shaped spacer 30. The external terminals 41 and 42 are bent outward at the lower end of the coil element 2. The spacer 30 is used to prevent the coils L of adjacent coil elements from coming into contact with each other and the electrodes 14 from coming into contact with each other, and is usually made of heat-resistant plastic or N.
It is made of a non-conductive magnetic material such as i-Zn ferrite.

[0007] The two flat coil elements 1 and 2 have a core.
In order to make the flat surfaces of the coils 10 face each other and prevent the coils 20 from being magnetically coupled to each other,
Are arranged so as to intersect at right angles, and are stacked and fixed via spacers 30. The electrode 14 has an external terminal 4
1, 42 are connected and fixed by soldering or the like. In addition, core 1
As shown by a two-dot chain line in FIG. 5, as shown by a two-dot chain line in FIG. However, the configuration can be such that the coils 20 do not contact each other. Moreover, in this case, if the winding axes 13 of the adjacent coil elements intersect at right angles, the magnetic coupling between the adjacent coils 20 is extremely small, and the magnetic flux passes through the flanges 11 and 12 of the cores 10 rather than each other. This will increase the inductance.

However, when three or more coil elements are stacked orthogonally to each other without the spacer 30, the winding axes 13 of the two separated coil elements are in the same direction.
Magnetic coupling may occur via the magnetic field. Therefore,
Even in a composite coil in which three or more coil elements are stacked, if it is desired to break the magnetic coupling between the two coil elements, a spacer 30 may be interposed between these coil elements. Due to the design, in the case of a composite coil that actively uses magnetic coupling, a configuration in which the spacer 30 is not used at all may be used. In the above embodiment, the frame-shaped spacer 30
However, a rod-like spacer 35 as shown in FIG.
It may be joined to the flanges 11 and 12 of the core 10.

FIG. 7 shows another embodiment of the core. This core
Reference numeral 50 denotes a structure in which another flange 57 is provided between the flange 51 and the flange 52 so that the coil can be wound in two. In this case, an electrode 54 for connecting a terminal or a tap of the coil 20 may be provided at the end of the flange 57 as shown in the figure.

[0010]

According to the present invention, a composite coil having a small mounting area and a low profile can be obtained, and a large inductance and a large Q can be obtained. In addition, since the coil elements can be easily manufactured by stacking coil elements in which coils are wound in advance, there is an advantage that productivity is good.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is a front sectional view of the same.

FIG. 4 is a plan view of a core.

FIG. 5 is a front sectional view of the same.

FIG. 6 is a perspective view showing another embodiment of the spacer.

FIG. 7 is a plan view showing another embodiment of the core;

[Explanation of symbols]

 10 Core 11 ・ 12 Flange 13 Roller shaft 14 Electrode 20 Coil 30 Spacer 41 ・ 42 External terminal

Claims (4)

(57) [Claims] 1. A plurality of cores made of a plate-shaped magnetic material having flanges at both ends of a winding shaft, the thickness of which is larger than the thickness of the winding shaft, and a terminal wound around the winding shaft of each core. A coil connected to an electrode provided on the flange and an external terminal connected and fixed to the electrode were provided, and a plurality of cores were stacked and fixed such that winding axes of adjacent cores crossed at right angles. A composite coil characterized in that: 2. An insulating spacer, comprising: two cores each having a flange protruding to one side in the thickness direction and one surface being flat and having a substantially U-shaped cross section, wherein the flat surfaces of each core are opposed to each other; 2. The composite coil of claim 1 stacked through. 3. The composite coil according to claim 1, wherein a plurality of cores each having a flange protruding on both sides in the thickness direction and having a substantially H-shaped cross section are stacked. 4. The composite coil according to claim 3, wherein an insulating spacer is interposed between at least two cores.