JPH0242704A - mutual induction coil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to mutual induction coils used in electronic equipment in each building.

Conventional technology Figure 4 is a circuit diagram of a general mutual induction coil, and L
l is the primary coil, L2 is the secondary coil, Tlt.

T12 indicates a terminal of the primary coil Lt, and T21 and T22 indicate terminals of the secondary coil L2.

FIG. 5 is a sectional view showing the conventional mutual induction coil shown in FIG. Third.
A fourth soldering land 2, 3.4 and 5 is provided.

Reference numeral 6 indicates a primary coil L1, which is constructed by winding an insulated conductor, for example, a polyurethane-coated copper wire, into a cylindrical shape, and the insulation coating is peeled off at both ends of the primary coil L1. second soldering land 2,
It is soldered to 3 with solder 7.

8 indicates a secondary coil L2, which is constructed by winding an insulated conductor, for example, a polyurethane-coated copper wire, into a cylindrical shape, and the insulation coating is peeled off at both ends, and the secondary coil L2 is formed by winding an insulated conductor such as a polyurethane-coated copper wire into a cylindrical shape. Fourth soldering land 4,
It is soldered to 5 with solder 7.

Note that the secondary coil 6 and the secondary coil 8 are magnetically coupled and arranged on the wiring board l.

FIG. 6 is another circuit diagram of the mutual induction coil, in which the same parts as in FIG. 4 are given the same reference numerals.

In FIG. 6, Lu indicates a part of the coil, which is constructed by sharing a part of the secondary coil L21.

Note that this FIG. 6 is equivalent to the circuit diagram shown in FIG. 4.

FIG. 7 is a sectional view showing the conventional mutual induction coil shown in FIG. 6, where IA indicates a wiring board, and first and second soldering lands 2A and 3A are provided.

6A indicates a coil constituting the primary coil Lll and the secondary coil L21, and is constructed by winding an insulated conductor, for example, a polyurethane-coated copper wire, into a cylindrical shape, and the insulation coating is peeled off at both ends of the coil 6A. 1. The leads 9 are soldered to the second soldering lands 2A and 3A with the solder 7, and the insulation coating at the intermediate portion is peeled off to form the intermediate tap.

Incidentally, a part of the coil L11 is formed by the part where the lead wire 9 is soldered from the part soldered to the first soldering land 2A to the coil 6, and the lead wire 9 of the coil 6A is soldered. The secondary coil L21 is comprised of the portion soldered to the second soldering land 3A.

Problems to be Solved by the Invention However, the above-mentioned conventional mutual induction coil has the following problems.

First, since the mutual induction coil shown in FIGS. 4 and 5 is composed of two parts, the secondary coil 6.8,
The cost of each coil 6.8 and the cost of each coil 6 on the wiring board l
．． 8 becomes expensive.

Then, the area of the wiring board 10 required to configure the mutual induction coil becomes larger, and the size of the wiring board 10 becomes larger.

Furthermore, if the number of turns of the negative and secondary coils 6.8 is small, each coil 6.8 cannot be made to stand upright on the wiring board 1, making it difficult to mount each coil 6.8.

Next, in the mutual induction coil shown in FIGS. 6 and 7, it is actually difficult to draw out the lead wire 9 for the intermediate tap from the intermediate portion of the coil 6A, making the coil 6A expensive.

The present invention is intended to solve these conventional problems, and it is an object of the present invention to provide a mutual induction coil that is low cost and easy to mount.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention provides a wiring board in which a first coil is provided in a wiring pattern, and a second coil in which an insulated conductor is wound in a cylindrical shape is connected to the first coil. It is arranged in such a way that it is magnetically coupled with.

Therefore, according to the present invention, the first coil of the wiring pattern provided on the wiring board and the second coil made of an insulated conductor are magnetically coupled to form a mutual induction coil.

Embodiment FIG. 1 is a sectional view showing a mutual induction coil according to an embodiment of the present invention, and FIG. 2 is a plan view of a wiring pattern of a first coil provided on a wiring board.

In FIG. 1, reference numeral 11 indicates a wiring board, for example, a copper-clad paper phenol laminate, and a circular wiring pattern 12 and a first coil that form a first coil as shown in FIG. 2 by etching. Second soldering land 13
, 14 are provided.

Reference numeral 15 indicates a second coil arranged horizontally, and is constructed by winding an insulated conductor, for example, a polyurethane-coated copper wire, into a cylindrical shape, and the insulation coating is peeled off at both ends of the first coil. It is soldered to second soldering lands 13 and 14 with solder 16.

Note that the insulating coating of the second coil 15 is removed by mechanical cutting, polishing, thermal melting, chemical melting, or the like.

The first coil and second coil 15 of the wiring pattern 12 are magnetically coupled.

Next, manufacturing of the above embodiment will be explained.

First, the insulation coating on both ends of the second coil 15 is peeled off, and the first coil on the wiring board 11 is peeled off. second soldering land 13,
After applying paste solder on top of 14, the second coil 1
5, both end portions of 1. Second soldering land 1
3 and 14, heat the entire body, and reflow the solder, so that both end portions of the second coil 15 become the same as the first coil 15. It is soldered to the second soldering lands 13 and 14.

As described above, according to the above embodiment, since one of the two coils is provided on the wiring board 11 as the wiring pattern 12, the coil that must be mounted is the second coil 1.
5, it becomes easy to mount the second coil 15, and the area of the wiring board 11 can be reduced, resulting in miniaturization.

Further, since there is no need to use a lead wire for drawing out the intermediate tap, it can be manufactured at low cost.

In the above embodiment, the second coil 15 is arranged horizontally, but it may also be arranged upright as shown in FIG. 3 (coil 15A). Although an example in which the insulated conductor is hollow has been described, the insulated conductor may be made of something other than a polyurethane-coated copper wire, or may have a cored structure, may be wound around a bobbin, or may have a molded structure.

The wiring board 11 is not limited to an etched copper-clad paper phenol laminate, but may also be a silver-clad glass epoxy laminate, a ceramic substrate, or the like.

Further, the first coil formed on the wiring board 11 using the wiring pattern 12 may be formed in a concentric shape other than a circular shape, such as a square shape, or a plurality of turns formed in a multilayered shape.

Further, if the first coil and the second coil 15 are magnetically coupled, the second coil 15 is connected to the wiring pattern 1.
It may be placed at a position shifted from directly above 2.

The method of connecting both end portions of the second coil 15 to the wiring board 11 may be other methods such as an insertion method instead of the surface mounting method.

Effects of the Invention As is clear from the above-mentioned embodiments, the present invention has a second coil in which an insulated conductor is wound in a cylindrical shape on a distribution board on which a first coil is provided in a wiring pattern. Since they are arranged in a magnetically coupled manner, the only coil that needs to be mounted is the second coil, which makes mounting the coil easier and reduces the cost of mounting the coil.

In addition, since the second coil formed by winding a conductor can be placed over the first coil formed using the wiring pattern, the area of the wiring board on which the second coil is mounted can be reduced. Since the number of coils is small, the size can be reduced, and since the distance between the two coils can be shortened, there is an effect that the magnetic coupling between the two coils can be made tighter.

Also, 1st. When the number of turns of the second coil is small, since the first coil is provided in a wiring pattern on the wiring board, there is an effect that the second coil can be made to stand upright.

Furthermore, even in the case of a single-turn type mutual induction coil with a center tap, it can be equivalently converted to a compound-turn type, so there is no need to provide a troublesome center tap, and it can be made smaller and cheaper on the wiring board. This has the effect that it can be configured as follows.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a mutual induction coil according to an embodiment of the present invention, FIG. 2 is a plan view showing a wiring pattern of a first coil provided on a wiring board, and FIG. 3 is a cross-sectional view showing a mutual induction coil according to an embodiment of the present invention. A cross-sectional view showing a mutual induction coil according to another embodiment of
5 is a cross-sectional view showing the conventional mutual induction coil shown in FIG. 4, FIG. 6 is another circuit diagram of the mutual induction coil, and FIG. 7 is a circuit diagram of the mutual induction coil. FIG. 7 is a sectional view showing the conventional mutual induction coil shown in FIG. 6; 11 - Wiring board, 12... Wiring pattern, 13
...First soldering land, 14...Second soldering land, 15, 15A...Second coil, 16...
·solder. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (2)

[Claims] (1) A wiring board on which a first coil is provided in a wiring pattern, a first soldering land and a second soldering land, an insulated conductor is wound in a cylindrical shape, and both ends are a mutual induction coil having an insulating coating peeled off and soldered to the first and second soldering lands, and a second coil arranged to be magnetically coupled with the first coil. . (2) The mutual induction coil according to claim 1, wherein the second coil is disposed substantially upright on the wiring board.