JPH05175049A - Flat coil and magnetic device using it - Google Patents

Abstract

PURPOSE:To reduce differences in an electric potential between two spiral conductors formed adjoining on the same insulating substrate and to shorten an insulation distance, whereby an attempt is made to miniaturize a flat and a magnetic device using this. CONSTITUTION:On an insulating substrate 10, spiral conductors 11a, 11b are so formed as to be connected to an outer peripheral end part to make a flat plate unit coil 21. This is laminated in a predetermined number so that an inner peripheral end may be alternately connected to an adjoining layer to constitute a flat coil 25. Respective spiral conductors are assembled to link with cores 31a, 31b to make a reactor. Also, the plurality of flat coils 25 are assembled to constitute a transformer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to magnetic parts such as transformers and reactors used in power supply devices such as switching regulators, and more particularly to a structure for reducing the size and thickness and simplifying the manufacturing process.

[0002]

2. Description of the Related Art As an example of a coil for a thin magnetic part using a flat coil, a plurality of spiral conductors on the same plane, which are described in Japanese Utility Model Publication No. 58-124917, are folded and overlapped to form one coil. Methods of constructing circuits have been proposed.
In this configuration, the spiral conductors that surround one core leg and are stacked are sequentially connected in the stacking order to form a coil.

[0003]

In the above-mentioned prior art, when two spiral conductors surrounding two legs forming a closed magnetic circuit via a yoke are formed on the same plane, the spiral conductors are laminated between the spiral conductors. It is necessary to provide an insulation distance corresponding to the number of series connections in the same direction, which has the drawback of increasing the coil size. An object of the present invention is to provide a structure capable of miniaturizing a flat plate coil for a transformer or a reactor, and to provide a thin transformer or a reactor using the flat plate coil.

[0004]

In order to achieve the above object, a plurality of spiral-shaped coils that are arranged on the same insulating substrate to form a flat coil on a plurality of legs of a magnetic core that forms a closed magnetic circuit via a yoke. In transformers and reactors in which conductors are placed, in order to shorten the insulation distance between two adjacent spiral conductors and reduce the size, the spiral conductors are formed by connecting the outer peripheral ends of the spiral conductors. The conductor was configured to interlink with two adjacent legs of the magnetic core.

[0005]

[Function] By connecting the outer peripheral ends of two spiral conductors formed on the same insulating substrate and interlinking with two adjacent legs of the magnetic core to make them have the same potential, the potential difference between the adjacent conductors is reduced. Since this can be reduced, the insulation distance between two adjacent spiral conductors can be shortened, and the overall dimensions of the transformer and reactor can be reduced.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a two-leg type reactor using a flat plate coil according to an embodiment of the present invention. As an example, two spiral conductors 11a, 1 having three turns are provided on one insulating substrate 10.
A plurality of unit plate coils 21 each having a shape in which 1b is connected to the outer peripheral ends thereof, 21a, 21b, 21 in this embodiment.
The three sheets of c are superposed, and the inner peripheral ends 11ai and 1 of each spiral conductor are
1bi alternately, that is, unit plate coils 21a and 21a
b is the inner peripheral edge 11ai, unit flat plate coils 21b and 21
c is the coil unit 22 by connecting the inner peripheral end 11bi
Make up. The unit plate coils 23 and 24 having an integral number of turns and 1/2, respectively, of 2 and 1/2 turns are stacked on both ends of the coil unit 22 to overlap the inner circumferential ends 23i and 2i.
4i is connected to the coil unit 22. As a result, in this embodiment, the flat coil 25 having 23 turns is constructed.

The reactor 1 can be constructed by disposing the bipodal cores 31a and 31b so as to interlink with the spiral conductors of the flat plate coil 25. The effect of constructing the reactor according to this embodiment will be described with reference to FIGS. FIG. 2 shows a concept of a configuration example of the reactor 2 in which the coils 26a and 26b are provided in the bipod type core 32 in the conventional structure.
2b each has a coil with a predetermined number of turns, and both are BC
In this example, points are connected in series. In this configuration, the potential of each part of the coil is, for example, A <B = C <D, and the potential difference between A′D ′ approaching in the window of the core 32 is almost equal to the potential difference between AD, which is the largest potential difference in this coil. Will be equal.
Therefore, it is necessary to secure a predetermined insulation distance between the coils 26a and 26b, which increases the overall size. On the other hand, in the flat plate coil 25 constructed according to the present embodiment shown in FIG. 3, the potential becomes A <B <C <D or D <C <B <A, and the points A and D having the largest potential difference are close to each other. Will disappear. As a result, it is not necessary to secure the insulation distance between the coils, and there is an effect that the entire device can be downsized.

Although the embodiment as a reactor coil has been described above, a transformer can be formed by adding another coil having the same structure to form two or more windings. Although FIG. 1 shows an example of the unit flat plate coil in which the spiral conductor is formed on one surface of the insulating substrate 10, the conductor may be formed on both surfaces.

As another embodiment of the present invention, a description will be given of an embodiment in which a unit flat plate coil having a plurality of layers is collectively formed on a single insulating substrate. In FIG. 4, unit flat plate coils 41 a, 41 b, 41 c for three layers are collectively formed on one insulating substrate 40 to form a composite flat plate coil body 42. By bending and stacking this at the mountain fold line 43 and the valley fold line 44 and electrically connecting predetermined portions, a laminated coil body corresponding to the coil unit 22 of FIG. 1 can be configured. In this case as well, it is possible to employ a composite flat plate coil body in which spiral conductors are formed on both surfaces of the insulating substrate 40.

A modified example of the above embodiment is shown in FIG. Unit plate coils 51a, 51b, 51c, 51 are formed on the insulating substrate 50.
The composite plate coil body 52 is formed by collectively forming d and 51e. A coil corresponding to the flat plate coil 25 in FIG. 1 can be configured by bending and stacking this at the mountain fold lines 53a and 53b and the valley fold lines 54a and 54b and electrically connecting predetermined portions. Also in this embodiment, the insulating substrate 5 is used.
The spiral conductors may be formed on both sides of 0.

According to the embodiments shown in FIGS. 4 and 5, since unit flat plate coils having a plurality of layers are collectively formed on the same substrate and are bent and laminated, the number of parts can be reduced and the manufacturing process can be simplified.

As still another embodiment of the present invention, a configuration example of a flat plate coil which constitutes a transformer or a reactor in combination with a multi-leg core having more than two legs will be described. FIG. 6 shows, as an example, six spiral conductors 61 a, 61 on one surface of the insulating substrate 60.
The flat plate coil 63 which formed b, 61c, 61d, 61e, 61f is shown. FIG. 7 shows the other side of the flat coil 63, on which spiral conductors 62a to 62f are formed at positions corresponding to the spiral conductors 61a to 61f. Spiral conductors 61a and 62 facing each other with an insulating substrate 60 in between.
a, 61b and 62b, ..., 61f and 62f are the innermost peripheral edge 6
1ai and 62ai, 61bi and 62bi, ..., 61fi
And 62fi are connected by a through hole or the like. According to this configuration example, there are 33 windings between the terminals 62ao and 62fo.
It becomes the flat plate coil 63 of one time. This flat coil 63 is shown in FIG.
By incorporating the multi-leg core 64 and the yoke 65 as shown in FIG. According to this embodiment, since it is not necessary to secure an insulation distance between the spiral conductors 61a and 61b, 61c and 61d, 61e and 61f whose outer peripheral ends are connected to each other, it is possible to reduce the overall size. . A transformer can also be configured by incorporating two or more flat plate coils in the same configuration as this reactor.

[0014]

According to the present invention, by connecting the outer peripheral ends of two adjacent spiral conductors on the same insulating substrate, the potential difference between the adjacent conductors is reduced and the insulation distance is shortened. The size of the coil can be reduced, and magnetic equipment such as transformers and reactors can be downsized.

[Brief description of drawings]

FIG. 1 is an assembly view of a bipod core type reactor using a flat plate coil according to an embodiment of the present invention.

FIG. 2 is a principle diagram showing a potential distribution of a conventional bipod core type reactor winding.

FIG. 3 is a principle diagram showing a potential distribution of a two-leg core type reactor winding according to an embodiment of the present invention.

FIG. 4 is a plan view of a composite flat plate coil body of a modified example of the present invention.

FIG. 5 is a plan view of a composite flat plate coil body of a modified example of the present invention.

FIG. 6 is a plan view of a flat coil for a multi-leg core according to another modification of the present invention.

FIG. 7 is a plan view of another surface of the flat coil for multi-leg core shown in FIG.

FIG. 8 is an assembly diagram of a reactor using a flat coil for a multi-leg core.

[Explanation of symbols]

1 ... Reactor, 10 ... Insulating substrate 21, 21a, 21
b, 21c, 23, 24 ... Unit flat plate coil, 22 ... Coil unit, 25 ... Flat plate coil, 31a, 31b ... Core.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriyuki Uchiyama 4026 Kuji Town, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi, Ltd.

Claims (2)

[Claims] 1. A coil for forming a magnetic device by forming a plurality of flat plate-shaped conductors surrounding a leg of a magnetic core forming a closed magnetic circuit via a yoke, the coils being arranged on the same insulating substrate, respectively. , Of the plurality of spiral conductors surrounding another core leg, connect the outer peripheral ends of two adjacent spiral conductors, and stack the inner peripheral end with a necessary insulation distance. A flat plate coil, which is configured by being connected to an inner peripheral end portion of a spiral conductor of a layer. 2. A magnetic device constructed by using the coil according to claim 1.