JPH01120087A - Wiring circuit board - Google Patents

Abstract

PURPOSE:To easily form a matrix-shaped electric circuit without using a multilayer wiring part, to prevent a short circuit and a defective connection, to make a wiring part highly dense and to lower a cost of a wiring circuit board by a method wherein a flexible board where a wiring pattern composed of two or more wiring conductors has been formed is folded. CONSTITUTION:The following are provided: an insulating flexible board 11 which can be folded; a wiring pattern 13 which has been formed on the flexible board 11 by two or more wiring conductors 12 having electrodes X, Y and connection parts 15 and where the individual connection parts 15 are arranged in parallel; an insulating film 14 which exposes the electrodes X, Y and the connection parts 15 in the wiring conductors 12 and which covers other parts. The flexible board 11 where said wiring pattern 13 and insulating film 14 have been formed is folded; the facing connection parts are connected to one another; a matrix-shaped electric circuit is formed. For example, two or more wiring conductors 12 composed of copper foil or the like are arranged in parallel on a flexible board 11 composed of a polyimide resin film or the like; a flexible insulating film 14 composed of a polyimide resin or the like is formed on it.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a wired circuit board used for forming a 71 to 90x circuit of a facsimile machine, a logic circuit network of an electronic computer, and the like.

(Prior Art) Conventionally, there have been technologies in this field as shown in FIGS. 2 to 4. The configuration will be explained below using figures.

FIG. 2 is a plan view of a printed circuit board on which a conventional matrix wiring circuit is formed, and FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2.
and FIG. 4 is an electrical circuit diagram of the wiring circuit board shown in FIG. 2.

In FIGS. 2 and 3, this wired circuit board has a matrix wired circuit formed on a board body 1 using multilayer wiring.

On the substrate body 1, a first layer wiring 2 is formed, for example, consisting of a large number of wiring conductors formed in a column direction.

These wiring conductors are Yll, respectively.

Y12. Y13~Yn1. Y, 2. Y, has 3.

An insulating film 3 having electrical insulation properties is formed on the substrate body 1 on which the first layer wiring 2 is formed. This insulating film 3 covers the electrodes Y11, Y12, . Y13～
Yo1. Y02. Although the portions excluding Y and 3 are covered, a pie hole 4 penetrating through the insulating film 3 is formed at a location corresponding to a predetermined position on each wiring conductor.

A second layer wiring 5 consisting of a plurality of wiring conductors formed in the row direction is formed on the insulating film 3, and these wiring conductors have electrodes X1 to X3. Although the second layer wiring 5 is insulated from the first layer wiring 2 by the insulating film 3, necessary connections are made through the pie hole 4.

That is, the second layer wiring 5 on the insulating film 3 is also formed in the via A7 hole 4, and is connected to the first layer wiring 2 through this.

In this way, each wiring conductor of the first layer wiring 2 formed in the column direction is connected to the wiring conductor of the second layer wiring 5 formed in the row direction via the piere hole 4, as shown in FIG. A matrix electric circuit as shown in the figure is formed.

The printed circuit board configured as described above is manufactured using thin film formation and etching technology, or thick film printing method, etc.
1@wiring 2, insulating film 3 and the second
This is done by forming layer wiring 5.

(Problems to be Solved by the Invention) However, the printed circuit board having the above configuration has the following problems.

(1) In order to form a matrix wiring circuit using complex multilayer wiring via the insulating film 3, short circuits may occur due to pinholes in the insulating film 3, and connection failures may occur due to failures in the via holes 4. There was a risk that this would occur.

(2) In order to reliably connect the first layer wiring 2 and the second layer wiring 5, it is necessary to form the pie hole 4 having a certain degree of serration. Therefore, the wiring density is restricted by the via hole 4, making it difficult to increase the wiring density.

(3) The process of forming a matrix wiring circuit using multilayer wiring is complicated and requires many steps. Therefore, it is difficult to reduce the cost of printed circuit boards.

The present invention provides a printed circuit board that solves the problems of the prior art, such as the possibility of short circuits and poor connections, the difficulty of increasing wiring density, and the difficulty of reducing costs. I have something to do.

(Means for Solving the Problems) In order to solve the above problems, the present invention includes a bendable insulating flexible substrate and a plurality of wiring conductors having electrodes and connection parts formed on the flexible substrate. the wiring pattern and the insulating film are formed, comprising a wiring pattern in which each of the connection parts is arranged in parallel, and an insulating film that exposes the electrode and the connection part of the wiring conductor and covers other parts. The wired circuit board is constructed by bending the flexible substrate and connecting the opposing connecting portions to form a matrix-like electric circuit.

(Function) According to the present invention, since the printed circuit board is configured as described above, the wiring pattern consisting of the flexible board and the plurality of wiring conductors formed on the flexible board is formed on the wiring conductors by being bent. The connected parts are connected facing each other to form a matrix-like electric circuit.

Furthermore, the insulating film prevents the bent wiring conductors from coming into contact with each other, thereby preventing short circuits.

Due to these functions, it becomes possible to easily form a matrix-like electric circuit without using multilayer wiring. Therefore, the above-mentioned problem can be eliminated.

(Example) FIG. 1 is a developed view of a printed circuit board showing an example of the present invention.
FIG. 5 is a perspective view of a printed circuit board according to an embodiment of the present invention, and FIG. 6 is a sectional view taken along the line B--B in FIG.

In FIG. 1, the main body of this printed circuit board is formed of an insulating flexible substrate 11 made of polyimide resin film or the like.

A plurality of wiring conductors 12 made of copper foil or the like are provided in parallel on the flexible substrate 11, and a wiring pattern 13 is formed by these wiring conductors 12. At one end of each wiring conductor 12, electrodes X1 to X
3 and electrode Y11°Y12. Y13~Yo1. Yo2.
Y03 is provided respectively.

A flexible insulating film 14 made of polyimide resin or the like is formed on the flexible substrate 11 on which the wiring pattern 13 is formed in this manner. The insulation tItA 14 is composed of a first insulation film 14-1 and a second insulation film 14-2, and the two insulation films 14-1 and 14-2 are provided in parallel in a direction perpendicular to the wiring conductor 12. ing. These insulating films 14-1, 14-2 cover electrodes X1 to X3 and electrodes Y11. Y12. It covers most of the wiring conductors 12 except for Y13 to Ynl"n2"n3, but the end of each wiring conductor 12 on the side where the electrode is not formed is exposed, and the first It constitutes a connecting portion 15-1. In addition, the first and second insulating films 14-1, 14-2
The respective wiring conductors 12 in the sandwiched portions are also exposed, forming second connection portions 15-2 arranged in parallel.

These exposed 1st. Second connection part 15-1.15-
The surface of 2 is plated with solder, for example.

The first connecting portion 15-1 and the second connecting portion 15-2 are arranged to face each other with the first insulating film 14-1 interposed therebetween. That is, they are arranged at symmetrical positions with respect to the center line C of the first insulating IW 14-1.

The flexible substrate 11 on which the wiring pattern 13 and the insulating film 14 are formed as described above is bent near the center line C (=J) as shown in FIGS. It is glued and fixed to the plate 16. By this bending, the first connection part 15-1 and the second connection part 15-2 are brought into contact with each other at symmetrical positions, and the pre-plated solder 17 connected by.

At this time, since the other portions of the wiring conductor 12 are covered with the first and second insulating films 14-1 and 14-2, there is no risk of short circuit.

In the wired circuit board configured as described above, for example, an electric signal input from the electrode X1 is transmitted to the wiring conductor 12-L first connection portion 15-1-L second connection portion 15-2-11, and is output to the electrode Y11 via the wiring conductor 12-11. Further, the second connecting portion 15-
2-11, the electrical signal passes through wiring conductor 12-11,
First connection part 15-1-IL Second connection part 15-2-2
1, and the electric wire Jfl Y 21 via the wiring conductor 12-21.
Output to. In this way, the electrical signal from electrode x1 is transmitted from electrode Y11. It is output to Y21 to Ynl.

Similarly, electrode x 2. The electric signals input from x3 are electric signals tMY12. Y22~Yn2 and Y13゜Y
23 to "n3. That is, a wired circuit board is constructed in which the matrix electric circuit shown in FIG. 4 is formed on the flexible substrate 11.

This embodiment has the following advantages.

(1) Multilayer wiring is not required, and therefore no pie holes are required, so there is no risk of short circuits or connection failures.

(ii) The wiring conductors 12 are connected by soldering or the like by bringing them into direct contact without using a pie hole.

Therefore, efficient connections can be made using the entire width of the wiring conductor 12, and wiring density can be increased.

(iii) A multi-layer wiring process is not required, and a matrix wiring circuit can be easily formed with a small number of man-hours, so that the cost of the wiring circuit board can be reduced.

Note that the present invention is not limited to the illustrated embodiment and can be modified in various ways, such as the following modifications.

(a> In FIG. 1, Yll, Y12.Y13 to Yn1°Y,
2. Although the configuration is a matrix wiring circuit made of Yn3, the present invention is not limited to this. For example, it is possible to change the number, arrangement, etc. of the input and output side terminals (*).Also, the present invention is not limited to matrix wiring circuits,
It is also applicable to printed circuit boards having various other circuits.

(b) In FIG. 1, the first and second connecting portions 15
-1.15-2 is a wiring conductor 12 without forming a special terminal.
Although we decided to use a part of it as is, it is not limited to this. For example, the thickness and width of the connection portions 15-1 and 15-2 may be made larger than other portions of the wiring conductor 12 to form connection terminals.

(C) The materials of the constituent members of the printed circuit board are not limited to those shown in the above embodiments.

For example, the material of the flexible substrate 11 may be a polyester resin film, or the insulating film 14 may be formed of a solder resist. Further, for the connection of the connecting portions 15-1 and 15-2, a botmelt material other than solder, a conductive adhesive, or the like may be used.

(d) The structure and shape are not limited to those shown in the drawings, and may be modified as necessary. For example, the base substrate 16 may not be provided, or one insulating film having an opening may be formed instead of the two insulating films 14-1 and 14-2.

(Effects of the Invention) As described above in detail, according to the present invention, a wiring pattern consisting of a plurality of wiring conductors is formed on a flexible substrate, and the flexible substrate is bent to make a predetermined connection to the wiring conductors. Since it is a printed circuit board,
A matrix-like electric circuit can be easily formed without using multilayer wiring. Therefore, short circuits and poor connections are prevented, and the reliability of the printed circuit board can be improved. Further, there is an effect that the wire hole is not required and the density of the wiring can be increased, and the number of man-hours is reduced due to the simplified manufacturing process, and the cost of the printed circuit board can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a developed view of a printed circuit board showing an embodiment of the present invention;
Fig. 2 is a plan view of a conventional printed circuit board, Fig. 3 is a sectional view taken along line A-A in Fig. 2, Fig. 4 is a matrix electric circuit diagram of the printed circuit board shown in Fig. 2, and Fig. 5 is a main A perspective view of a printed circuit board according to an embodiment of the invention, and FIG. 6 is taken along line B-B in FIG.
FIG. 11...Flexible board, 12...
Wiring conductor, 13...Wiring pattern, 14...
...Insulating film, 15-1...First connection part, 1
5-2...Second connection part, x1 to x3. Y11
．． Y12. Y13~Yo1゜Yn2. Yn3”-・-i
+i. Applicant's agent Kyo Kakimoto A-△ of Acid Figure 2
Line cross-sectional view Figure 3 Matrix electrical circuit diagram of Figure 2 Figure 4

Claims (1)

[Claims] a bendable insulating flexible substrate, a wiring pattern formed on the flexible substrate by a plurality of wiring conductors having electrodes and connection parts, and each of the connection parts being arranged in parallel; A matrix-shaped electric circuit is formed by bending the flexible substrate on which the wiring pattern and the insulating film are formed, and connecting the opposing connecting parts to each other, comprising an insulating film that exposes electrodes and connecting parts and covers other parts. A printed circuit board characterized by forming: