JP2000164431A - Inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize an inductor at a low DC resistance by a method wherein a rectangular copper wire or a punched copper plate is incorporated between U type and I type magnetic cores, in such a way that both ends in the longitudinal direction of the copper wire or the punched copper plate are exposed. SOLUTION: An inductor is constituted of a U type magnetic core 1 consisting of a ferrite, an I type magnetic core 2 consisting of a ferrite and a rectangular copper wire 3. The copper wire 3 may be one with an insulation covering or one free from an insulation covering and may be a punched copper plate. The core 1 has a recess capable of housing the copper wire 3. The copper wire 3 is incorporated between the cores 1 and 2 in such a way that both ends in the longitudinal direction of the copper wire 3 are exposed and the copper wire 3 is fixed between the cores 1 and 2 by a holder or the like to form the inductor. A heat-resisting spacer 5 consisting of a polyester or polyimidine film or the like is inserted between the cooper wire 3 and the core 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to various power supply devices,
The present invention relates to inductors used in video equipment, audio equipment, industrial equipment, communication / information-related equipment, and the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 9, a flat copper wire 23 is wound around a cylindrical jig for at least two turns as shown in FIG. E-type magnetic core 21 or E-type and I-type magnetic cores are incorporated.

However, in such a shape, there is a problem that although the inductance value can be increased, the DC resistance increases. Further, there is a problem that the shape becomes large when the DC resistance is reduced.

On the other hand, in recent years, DC / DC converters and the like having high efficiency have been required to have low DC resistance even though the inductance value is low.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a small inductor with low DC resistance.

[0006]

The present invention is characterized in that a flat rectangular copper wire or a stamped copper plate is incorporated into a U-shaped or I-shaped magnetic core so that both ends in the longitudinal direction are exposed. It is an inductor.

[0007] The present invention also provides a flat copper wire or a punched copper plate, wherein a portion to be a mounting terminal is crushed by pressing.
The above inductor is characterized in that it is thin.

Further, the present invention is the above-mentioned inductor, wherein both ends of the rectangular copper wire or the stamped copper plate are bent to form surface mounting terminals.

Further, the present invention is the above-mentioned inductor, wherein the rectangular copper wire or the stamped copper plate is molded with an insulating resin.

The inductor manufactured by using the above means is
The DC resistance can be easily reduced, and the size of the product can be reduced.

[0011]

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

FIG. 1 shows an inductor according to a first embodiment of the present invention. As shown in FIG. 1, the inductor according to the first embodiment includes a U-shaped magnetic core 1 made of ferrite,
It comprises an I-shaped magnetic core 2 made of ferrite and a rectangular copper wire 3 having a rectangular cross section and a plate shape. The rectangular copper wire may be provided with or without an insulating coating, or may be a stamped copper plate. The U-shaped magnetic core 1 has a recess in which the rectangular copper wire 3 can be accommodated. According to the inductor of the present invention, the rectangular copper wire 3 is connected to a U-shaped magnetic core 1 and an I-shaped magnetic core 2.
And fixed by a holder or the like. At this time, a heat-resistant spacer 5 such as a polyester or polyimide film is inserted between the rectangular copper wire 3 and the core.

FIG. 2 shows an inductor according to a second embodiment of the present invention. The configuration is the same as that of the first embodiment, and only the shape of the terminal is different. That is, as shown in FIG. 2, the end of the rectangular copper wire 3 serving as a mounting terminal is pressed and crushed to increase the mounting area. This allows
The stability during mounting on the substrate is improved.

The inductor shown in FIGS. 1 and 2 is used for a substrate 11 having a through hole for receiving a product as shown in FIG.

FIG. 4 shows an inductor according to a third embodiment of the present invention. In this example, the flat copper wire 3 is bent in the mounting direction to form a terminal, and the inductor is formed so that the bottom face and the tip end of the inductor coincide with each other.

FIG. 5 shows an inductor according to a fourth embodiment of the present invention. FIG. 6 shows a fifth embodiment of the present invention.
2 shows an inductor in FIG. These examples show a flat copper wire 3
Is bent to form a surface mount type terminal.

As shown in FIG. 7, the inductor of the example of FIGS. 5 and 6 first bends a rectangular copper wire 3 into a predetermined shape, and then incorporates an I-shaped magnetic core 2 into this. It is manufactured by incorporating a U-shaped magnetic core 1. In the example of FIG.
After pressing and crushing both ends of the rectangular copper wire, it is bent.

In particular, in the example of FIG. 6, by crushing the mounting surface of the terminal by pressing, not only the stability at the time of mounting on the substrate is good, but also the height of the product can be reduced.

FIG. 8 shows an inductor according to a sixth embodiment of the present invention. In this example, the rectangular copper wire 3 is
It was molded by The terminal is a surface mount type,
The contact surface between the side surface and the substrate is exposed. With this structure, insulation between the core and the coil (copper wire) can be ensured.

Next, the characteristics of the present invention (FIG. 6) and a conventional inductor were compared. The dimensions of the inductor of the present invention are shown in FIG.
As shown in the figure, the length A is 10.0 mm, the width B is 9.5 mm, and the height C is 5.5 mm. The dimensions of the rectangular copper wire are 16 mm in length, 4 mm in width, and 0.5 mm in thickness, and the ends thereof are pressed to 0.2 to 0.3 mm.
mm in thickness. In addition, the conventional inductor has a four-turn winding made of a rectangular copper wire. The DC resistance was 0.2 mΩ in the present invention and 1.5 mΩ in the related art. The inductance was 20 A, 0.35 μH in the present invention, and 2 μH in the related art.

[0021]

As described above, according to the present invention, it is possible to provide a small inductor with a low DC resistance required for a large current.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an inductor according to a first embodiment of the present invention. FIG. 1A is an exploded perspective view. FIG. 1B is an external perspective view. FIG. 1C is a side view.

FIG. 2 is an explanatory diagram of an inductor according to a second embodiment of the present invention. FIG. 2A is an external perspective view of the inductor. FIG.
(B) is a side view showing the state of the terminal before pressing. FIG.
(C) is a side view showing the state of the terminal after pressing.

FIG. 3 is an external perspective view illustrating a usage state of the inductor according to the first and second embodiments of the present invention.

FIG. 4 is an explanatory diagram of an inductor according to a third embodiment of the present invention. FIG. 4A is an external perspective view. FIG. 4B is a side view.

FIG. 5 is an explanatory diagram of an inductor according to a fourth embodiment of the present invention. FIG. 5A is an external perspective view. FIG. 5B is a side view.

FIG. 6 is an external perspective view of an inductor according to a fifth embodiment of the present invention.

FIG. 7 is a side view showing the method for manufacturing the inductor according to the fifth embodiment of the present invention. FIG. 7A is a side view of a rectangular copper wire. FIG. 7B is a side view showing a state where the rectangular copper wire is bent. FIG. 7C is a side view showing a state where an I-type magnetic core is incorporated. FIG. 7D is a side view showing a state in which a U-shaped magnetic core is incorporated. FIG. 7E is a side view of the completed inductor.

FIG. 8 is an explanatory diagram of an inductor according to a sixth embodiment of the present invention. FIG. 8A is an exploded perspective view. FIG. 8B is an external perspective view. FIG. 8C is a cross-sectional view of a rectangular copper wire molded with an insulating resin.

FIG. 9 is an exploded perspective view of a conventional inductor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 (U type) magnetic core 2 (I type) magnetic core 3,23 Flat copper wire 4 Insulating resin 5 Heat insulating spacer 6 Press machine 10 Inductor 11 Substrate 12 Land 21 E-type magnetic core A Length B Width C Height dimensions

Claims (4)

[Claims] 1. A flat rectangular copper wire or a punched copper plate,
An inductor, which is incorporated in U-shaped and I-shaped magnetic cores such that both ends in the longitudinal direction are exposed. 2. The inductor according to claim 1, wherein a portion of the rectangular copper wire or the punched copper plate, which is to be a mounting terminal, is crushed by a press to reduce the thickness. 3. A flat mounting terminal according to claim 1, wherein both ends of said rectangular copper wire or stamped copper plate are bent to form surface mounting terminals.
Or the inductor according to 2. 4. The inductor according to claim 1, wherein the rectangular copper wire or the stamped copper plate is molded with an insulating resin.