JPS63111692A - Printed board - Google Patents

Abstract

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

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is directed to a printed circuit board, specifically, when a first and a second printed circuit board are bonded by thermo-pressure with an anisotropic conductive thin film interposed therebetween, the first and second printed circuit boards are The present invention relates to a printed circuit board in which a predetermined conductor portion of a second printed circuit board is prevented from shifting (electrically connected).

[Conventional technology]

BACKGROUND ART In recent years, portable electronic calculators (pocket calculators), portable audio products, and the like are preferred to be light, small, short, and thin.

On the other hand, the portable audio products and the like are equipped with a large number of functions, and accordingly, a large number of electronic components such as integrated circuits and transistors are being mounted thereon.

For this reason, it is necessary to mount electronic components and the like at high density inside the casing of portable audio products and the like.

As one means of high-density mounting, a large number of electronic components are mounted on a first flexible printed circuit board (hereinafter referred to as FP board), and a large number of electronic components are mounted on a separate second flexible printed circuit board. Implement it. A method is used in which the first and second FP substrates are electrically connected through an anisotropic conductive thin film.

Here, "double series of anisotropic conductive thin films" means, for example, a thickness of 3
0~35μm, width is 4mm, length is 50m
It has the property (anisotropy) that no current flows in the horizontal direction (the plane direction of the film), but only in the vertical direction (the thickness direction of the film). There is.

Here, using FIGS. 4 and 5, connect the first FP board and the second FP board.
A method of electrically connecting these first and second FP substrates by interposing an anisotropic conductive film between them and the P substrate will be described.

As shown in FIG. 4, the first FP board 101 has a rectangular shape, and a narrow strip of copper Yi 102 is provided on the lower surface of the right edge.
a, 102b, and 102cm are formed parallel to each other.

On the other hand, copper foils 104a, 104b, 104c...
... is formed. Then, the first FP board 1
The copper foils of each of 01 and the second FP board 103 are 102a.
and 104. a, 102b and ]-04b.

102c and 104c, . . . are constructed in such a size and shape that copper foils corresponding to each other are electrically connected.

The first and second FP boards 101 configured in this way
and 103 are arranged so that their edges overlap as shown in FIG. 5, and the copper foils 102a and 104a...
An anisotropic conductive film 105 is placed between the two, a predetermined pressure is applied from the directions of arrows x and y, and a temperature of approximately 200° C. is further applied for several tens of seconds. Then, the first FP board 101 and the second FP board 03 are bonded together by thermocompression via the anisotropic conductive film 105, and the corresponding copper foils are electrically and firmly connected to each other. .

[Problem to be solved]

By the way, in the case of the above-mentioned high-density mounting printed circuit board, the copper foils 102a, 102 as shown in FIG.
b, 102c may be arranged 2 to 4 pieces per 1 mm, and naturally in this case, the second FP board 10
No. 3 copper foil 104a.

104b, 104c, etc. are also naturally 1
This means that 2 to 4 trees are formed per mm.

In such a case, as described above, the copper foils 102a and 104a, the copper foils 102b and 104b, the copper Fi 102
(It is necessary to make an electrical connection, and if this happens, it will naturally become impossible to perform the specified operation.)

Conventionally, in order to electrically connect copper foils to each other in which even the slightest misalignment is not allowed, the above-mentioned needs have been met by using an image processing device having an optical sensor, camera, or the like.

Furthermore, when connecting printed circuit boards through an anisotropic conductive foil film using conventional image processing, optical means are used, so both or at least one of the first and second FP boards must be transparent. did not become.

Moreover, the image processing device described above is expensive, and it is hoped that there will be a way to easily make it mechanically strong without causing misalignment between the copper foils, and electrically to flow accurate current. It was wanted.

[Means for solving problems]

In order to solve the above problems, the present invention provides a printed circuit board in which predetermined conductors formed on a first and second printed circuit board are electrically connected to each other by interposing an anisotropic conductive thin film. , a guide conductor part is formed near the contact part of each conductor of the first and second printed circuit boards, and if the predetermined guide phase conductor parts are correctly connected, it is detected by electrical means that they are correctly connected. It was designed to do so.

Further, a plurality of guide conductor parts are formed on one printed circuit board with a predetermined width apart, and a guide conductor part slightly narrower than the above-mentioned predetermined width is formed on the other printed circuit board. If the comrades are shifted from each other, the conductor portions formed on one and the other printed circuit boards will come into contact with each other.

[Effect]

As described above, the present invention includes forming guide conductor parts on the first and second printed circuit boards, in addition to the conductor parts (copper foil) for demonstrating the functions of the electric circuit of portable audio products, etc. ing. When the first and second printed circuit boards are temporarily placed opposite each other, it is determined by electrical means whether the guide conductors are in proper contact with each other, and if they are in proper contact, thermocompression welding is performed. , if they are not in contact with each other in the correct facing position, a message is displayed to indicate that the thermocompression welding should be performed after correcting the positions so that they are facing each other correctly.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The printed circuit board of the present invention will be explained below based on illustrated embodiments.

Figure 1 is a diagram schematically showing the case where the first and second printed circuit boards are placed correctly, and Figure 2 is a diagram schematically showing the case where the first and second printed circuit boards are misaligned. This is a diagram.

As shown in FIG. 1, the back surface of the left lower edge of the first FP board 1o has strip-shaped first to third guide conductor parts 1a, I
b, Ic are formed in parallel, and the gap between these guide conductor parts 1a, Ib, lc is slightly narrower than the width of the conductor. Further, on the upper right edge surface of the first FP board 1o, fourth to sixth guide conductor parts 1d, I
e, ], f are formed in parallel rectangular shapes. and,
Strip-shaped first to third connection conductor portions 2a, 2b, and 2c are formed in parallel in the intermediate portions of the guide conductor portions formed on the left and right back surfaces of the first FP board 10, One end of each is connected to an electronic circuit component (not shown).

On the other hand, a strip-shaped first guide conductor portion 21a is formed on the left upper edge surface of the second FP board 2o, and a second
A second guide conductor 21b is formed on the right upper edge surface of the FP board 20.

These first and second guide conductors 21a and 21
Connecting conductor portions 22a and 22b are provided between the connecting conductor portions 22a and 22b.

22c is formed, and these conductor parts 22a to 22
C are formed at positions corresponding to the connection conductor portions 2a, 2b, and 2c formed on the first FP board 1o, respectively.

In addition, ammeters 11a, 11 are connected to the first to third guide conductor portions 1a, lb, lc of the first FP board 1o, respectively.
Lead wires extending from one end of the ammeters 11a to 11c are connected to the lead wires extending from one end of the ammeters 11a to llc, and the other ends of the ammeters 11a to IIC are connected to the + side of a DC power supply 12, and an example of this DC power supply 12 is a protective resistor. 13 of the second FP board 2o.
The guide conductor portion 21a is connected to the guide conductor portion 21a.

Similarly, one ends of ammeters 14c to 14a are connected to the fourth to sixth guide conductor parts 1d to 1f, respectively, and the other ends of these ammeters 14c to 14a are connected to the + side of the DC power supply 15. One side of this power source 15 is connected via a protective resistor 16 to a second guide conductor portion 21b formed on the second FP board 2°.

Although the anisotropic conductive film is not shown in FIG. 1, the anisotropic conductive film is provided at the position shown in FIG. 5.

In order to confirm that the first and second FP boards 10 and 20 configured in this manner are correctly arranged without being misaligned, the following procedure may be performed.

That is, in the case shown in FIG. 1, the first and second FP boards 10
and 20 are cases where they are correctly arranged without misalignment, and in this case, the second guide conductor part 1b of the first FP board 10 and the first guide conductor part 1b of the second FP board 20 The conductor portion 21a is in contact with the guide conductor portion 21a.
is not in contact with the other guide conductor portions 1a and 1c.

That is, in this case, since the guide conductor parts 1b and 21a are in contact, an electrical path is completed, and the ammeter 11
The needle b will swing. In this case, the first
Since no current flows through the third ammeters 11a and llc, the needles of these ammeters do not swing.

Similarly, the fifth guide conductor portion 1 of the first FP board 1o
e and the second guide conductor portion 21b of the second FP board 2o.
Since they are in contact with each other, the needle of the fifth ammeter 14b swings, but the needles of the fourth and sixth ammeters 14a and 14C do not swing and remain as they are.

Further, if the first and second FP boards IO and 20 are misaligned, the state shown in FIG. 2, for example, will occur. That is, in this case, the first guide conductor part 21a of the second FP board 20 contacts the first and second guide conductor parts 1a and 1b of the first FP board 10 at the same time. Become. In this case, the needles of the second and third ammeters 11b and llc will swing, and the needle of the first ammeter 112 will not swing and will remain as it is. Similarly, the needles of the fifth and sixth ammeters 14b and 14C swing, but the needles of the fourth ammeter 1
The 4.2 hand does not swing and remains as it is.

That is, as shown in FIG. 1, the first and second F
If the P substrates 10 and 20 are facing each other, the second ammeter 1
1b and the fifth ammeter 14b, but if they shift as shown in Fig. 2, the needles of the first and fourth ammeters 113 and 142 will also move. This means that both of them are swinging. In such a case, it is determined that the first and second FP boards 10 and 20 are misaligned with each other, so this can be corrected so that there is no misalignment as shown in FIG. .

Further, in order to improve the accuracy of the misalignment between the first and second FP boards, the method shown in FIG. 3 may be used.

As shown in FIG. 3, the first FP board 30 and the second FI
A J plate 40 is arranged to face the J plate 40. And the first FP
On the upper left edge surface of the substrate 30, first and second guide conductor parts 31a and 31b in the form of strips are arranged with a width W apart. Further, on the right upper edge surface of the first FP board 30, there are 3rd and 4th . a fifth guide conductor portion 31c;
31d and 31e are formed.

Connection conductor parts 322 to 32d are formed between these guide conductor parts formed on the left and right sides.

On the other hand, a first guide conductor part 33a is formed on the left upper edge surface of the second FP board 40, and the width of this guide conductor part 33a is V.
This width V is slightly narrower than the width W formed in .

Further, a second guide conductor portion 33b is formed on the upper right edge surface of the second FP board 40.

Between these first and second guide conductor parts 33a and 33b are connection conductor parts 34a to 34. d is formed.

When the first and second FP boards 30 and 40 are arranged correctly, the first guide conductor part 33a formed on the second FP board 40 is connected to the first FP board 40. The first and second guide conductor portions 3 formed at 30
This corresponds to the gap of width W between 1a and 31b. That is, in this case, the guide conductor part 33a formed on the second FP board 40 should not come into contact with either of the guide conductor parts 31a and 31b formed on the first FP board 30. becomes. Then, the first FP board 30
The fourth guide conductor portion 31d formed on the second guide conductor portion 33 formed on the second FP board 40
b will come into contact with.

Further, if the first and second guide conductor parts 30 and 40 are misaligned with each other, the guide conductor part 31d of the first FP board 30 and the second guide of the second FP board 40 Even if the guiding conductor portion 33b of the first FP board 30 and the second FP
If the guide conductor portion 33a of the substrate 40 is in contact with the guide conductor portion 33a,
This causes an ammeter (not shown) to swing. In other words, the accuracy is higher than that obtained with the guide conductor shown on the right side of Figure 3.
The accuracy obtained with the guide conductor shown on the left side is higher.

In the case of the embodiment shown in FIG. 3, the smaller the difference between the width W and the width ■, the more accurate it becomes possible.

In this embodiment, an ammeter is used as a means for detecting that the guide conductor is in contact, but an ammeter may not be used at all. For example, a light bulb (lamp) may be used instead of an ammeter, and of course any means for detecting that the ground current is flowing may be used.

〔effect〕

According to the present invention, by forming guide conductor parts in necessary parts of the printed circuit board, it becomes possible to detect misalignment between two printed circuit boards to be welded by heat pressure using a simple device. .

Further, since the present invention does not use an optical sensor such as a camera, it is possible to easily detect displacement of the printed circuit board even if the temporary printed circuit board 1 is opaque.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a case where the printed circuit board of the present invention is not misaligned, Fig. 2 is a front view when the printed board of the present invention is misaligned, and Fig. 3 is a front view showing a modification of the present invention. ,
FIGS. 4 and 5 are a front view and a side view of a case where a first and second printed circuit board are bonded by thermocompression with a conventional anisotropic conductive thin film interposed therebetween. 1a-If, 31a-31e...Guide conductor portion of the first printed circuit board, 2a-2c, 32a-32d...Connection conductor portion of the first printed circuit board, 21a, 21b, 33a, 33b...Guiding conductor portion of second print I/board, 11a to 1.1c, 14a to 14c......
...Ammeter (electrical detection means), 101...First printed circuit board, 103...
...Second printed circuit board, 105...Anisotropic conductive film. Applicant NEC Baum Electronics Co., Ltd. Agent Patent Attorney Masu 1) Takeo ■a

Claims (1)

[Claims] 1. A printed circuit board in which predetermined conductors formed on the first and second printed circuit boards are electrically connected to each other with an anisotropic conductive thin film interposed therebetween. Guide conductor portions are formed near the contact portions of the respective conductors of the second printed circuit board, and if the predetermined guide conductor portions are correctly connected, the correct connection is detected by electrical means. A printed circuit board characterized by: 2. A plurality of guide conductor portions are formed on one printed circuit board with a predetermined width apart, and a guide conductor portion slightly narrower than the predetermined width is formed on the other printed circuit board. Claim 1 characterized in that if the comrades are shifted from each other, the conductor portions formed on the respective printed circuit boards of one and the other come into contact with each other.
Printed circuit board as described in section.