JPH02205387A - Circuit wiring board device - Google Patents

Abstract

PURPOSE:To prevent the erroneous operation of a circuit and to improve yield at the time of manufacturing by forming the connecting wiring terminals of first and second circuit wiring boards to be narrower than the circuit wiring terminals and its interval at least at its base end. CONSTITUTION:The connecting wring terminals 21a of first and second circuit wiring boards 18 are formed to be narrower than circuit wiring terminals 21 and its interval (g) at least at the base 20 end. Since the interval between a plurality of connecting wiring terminals 20a can be increased whole holding high density of the boards 18 at the adjacent base 20 end of the boards 18, when the boards 18 are adjacently connected, an unnecessary short-circuit of the terminals 21 that showed not to be connected is prevented without request of high accuracy for setting of positions. Thus, it can prevent the erroneous operation of the circuit, easily electrically connect between the boards and improve yield at the time of manufacture.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to improvements in circuit wiring board devices used in electrical products and the like.

(Prior Art) In general, in electrical products using electronic components such as cameras, video equipment, OA equipment, and LCD televisions, circuit wiring boards have been used to reduce the size and weight of the products, especially in recent years. In order to make products smaller and thinner, there is a need to develop circuit wiring boards with higher density.

For this reason, for example, in the case of liquid crystal display devices used in liquid crystal televisions, the liquid crystal display panel used for display is often structured so that it is not possible to attach a circuit wiring board to the back side because light is applied from the back side for backlighting. . For this reason, circuit wiring boards are arranged along the four sides of the panel to be directly connected to a large number of leads led out from the panel. For connection work and to fit the casing that holds and fixes the panel,
The board is made flexible, and the circuit wiring boards of each board attached to each side of the panel are electrically connected to each other by connectors at the four corners of the panel.

That is, the conventional structure will be explained with reference to FIGS. 13 to 17. As shown in FIGS. 13 and 14, a printed circuit wiring board 13 made of a flexible base II supporting circuit wiring terminals IO is conductively connected to four sides around the liquid crystal display panel 14. As shown in FIGS.

Next, a connection wiring terminal 1 is extended from the circuit wiring terminal 10 for electrically connecting adjacent circuit wiring boards 13.
0a between adjacent circuit wiring boards 13 with a slight gap (
s) and bend the circuit wiring board 13 so as to butt against each other to form a connection part L3a, and further electrically connect the circuit wiring board 13 via the connection connector 1B soldered to the connection wiring terminal 10a. It is something.

More specifically, as shown in FIG. 14, in order to make the device smaller and lighter, the circuit wiring board 13 is wired at a high density, so that multiple circuits on the base 11 are wired at the same pitch. For example, the width of the circuit wiring terminal 10 is 0.5 [mm], whereas the interval (g) between the circuit wiring terminals is narrowed to 0.3 [mm].

Moreover, the surface of the circuit wiring board 13 is metallized by electrolytic plating to improve reliability, and the connection wiring terminal 10a extended from the circuit wiring terminal 10 is a plating lead when the circuit wiring board 13 is electrolytically plated. Since it is also used as a connector, it must reach the tip of the connecting portion 13a.

Further, as shown in FIG. 15, to explain the connection connector 16 in detail, the connection connector 16 has a plurality of connector conductor portions 16a arranged in parallel at the same pitch as the connection wiring terminals 10a.
and a connector connection part tab made of a heat-resistant organic film, and the connection part 1 of the first circuit wiring board 11x and the second circuit wiring board t3y that are adjacent to each other with a gap (s) provided therebetween.
After the connecting connectors 1B are stacked so that the connectors 3xa and 13ya and the connector connecting portions 18b face each other and are in contact with each other, the connecting wiring terminals 10a and the connector conductor portions lea are soldered.

However, in such a circuit wiring board, adjacent connection parts 13a connected by connection connector IB
The bending directions of the comrades are different from each other, and the first circuit wiring board 1
3x, there is a degree of freedom in the X direction of the plane coordinates, (
-) side, it will come into contact with the second circuit wiring board 13y, and furthermore, the second circuit wiring board t3y has a degree of freedom in the Y direction of the plane coordinates, and it However, if the distance between the connection wiring terminals exceeds the length (g), the connection wiring terminals of both circuit wiring boards 13x and L3y that should not be connected, for example, *A and * in Fig. 16, *
There is a problem that a short circuit occurs between the mouth and the mouth, causing a malfunction.

Conventionally, in order to prevent malfunctions due to such short circuits, the spacing (g) between the connecting wiring terminals was set to be wider than the width of the connecting wiring terminals, but the connecting portion 13a and, by extension, the circuit wiring board 13 became larger. This poses a problem in that it impedes miniaturization.

Another short-circuit prevention method is to not extend the connection wiring terminal 10a to the base end of the connection part 13a, but since the connection wiring terminal 10a also acts as a wire lead, In the case of not using a plating lead, another wiring serving as a plating lead is required, which again poses a problem of hindering miniaturization.

On the other hand, in the circuit wiring board 13, in order to cover the surface of the circuit wiring terminal 10 on the circuit wiring portion 11b of the base 11,
Conventionally, an insulating protective layer 12 as shown in FIG. 14 is provided.

That is, the insulating protective layer 12 has an edge 12a that separates the circuit wiring terminal from the connection wiring terminal and is formed in a straight line. Conductor connection part 11 between matching circuit wiring boards 3
The connection wiring terminals 10a on a are facing each other and connected with solder 9.

However, in such a circuit wiring board 13,
If an unreasonable force is applied to the connection part after connecting a plurality of circuit wiring boards 13, stress will be concentrated near the edge 12a of the insulation protective layer of the base 11 where each layer is thin, and the first
As shown in FIG. 8, the circuit wiring board 13 is easily broken and becomes unusable, which is a problem in terms of strength.

(Problem to be Solved by the Invention) Conventionally, it has been attempted to electrically connect adjacent circuit wiring boards with high-density wiring and the spacing between circuit wiring terminals being narrower than the width of the circuit wiring terminals. However, if adjacent circuit wiring terminals are not matched precisely, circuit wiring terminals that should not be connected may be short-circuited, which may cause the circuit to malfunction. If the board is flexible, if force is applied to the points where adjacent parts are connected, stress will be concentrated at the edges of the insulating protective layer, causing the circuit wiring board to break. are doing.

Therefore, the present invention aims to eliminate the above-mentioned problems, and makes it possible to reduce the size and weight of a circuit wiring board, and furthermore, without sacrificing its high density, when connecting with another circuit wiring board, different circuit wiring terminals can be used. By preventing short circuits, it is possible to prevent circuit malfunctions and improve manufacturing yields, as well as improve the strength of the conductor connections between circuit wiring boards and prevent bends that occur at the connections between circuit wiring boards. By preventing
The object of the present invention is to provide a circuit wiring board device that can extend the life of the circuit wiring board and further improve its reliability.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a flexible base and a plurality of circuit wirings provided on the base at a predetermined interval and having a width wider than the interval. A first terminal comprising a terminal and a plurality of connection wiring terminals extending from these circuit wiring terminals to the base end.
a circuit wiring board, a flexible base, a plurality of circuit wiring terminals provided on the base at predetermined intervals and having a width wider than the intervals, and a plurality of connection wiring terminals extending from the circuit wiring terminals to the end of the base. a second circuit wiring board installed adjacent to the base end of the first circuit wiring board so that its base end abuts against the base end of the first circuit wiring board; and a second circuit wiring board that straddles the first and second circuit wiring boards. In a circuit wiring board comprising a connector for electrically connecting connection wiring terminals of these boards, the connection wiring terminals of the first and second circuit wiring boards are wider than the circuit wiring terminals and the interval width thereof at least at the base end. The present invention provides a circuit wiring board device characterized in that the width of the circuit board is narrow.

Further, in the circuit wiring board device, a connection portion of one of the connection wiring terminals of the first and second circuit wiring boards also serves as a connection connector and is overlapped with a connection portion of the other connection wiring terminal.

Further, the circuit wiring terminal is covered with an insulating protective layer, and the connecting wiring terminal is exposed and extended from the edge of the insulating protective layer, and the edge of the insulating protective layer is between the circuit wiring terminal and the connecting wiring terminal. The circuit wiring board device is characterized in that the circuit board device is characterized by having an uneven linear shape across the board.

(Function) According to the present invention, at the adjacent base ends of the circuit wiring board,
Since the spacing between multiple connection wiring terminals can be expanded while maintaining the high density of the circuit wiring board, it is possible to connect circuit wiring boards adjacently without requiring high accuracy in position setting. To prevent unnecessary short circuits between circuit wiring terminals that are not connected to each other. Since the mechanical strength at the end of the insulation protection layer of the circuit wiring board can be increased, the circuit wiring board will not break even if force is applied to the connection part after the circuit wiring boards are connected adjacently. It is possible to improve the reliability of a circuit wiring board with high-density wiring.

(Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. 1 to 7.

FIG. 1 shows a liquid crystal display device 17, and the liquid crystal display panel 17
A circuit wiring board 18, which is a circuit wiring board, is provided around a.

This circuit wiring board 18 is made of a polyimide film with a thickness of 25 [μm], and includes a flexible base 20 that constitutes a conductor connection portion 20a and a circuit wiring portion 20b, and a thickness of 1 g [μm].
μl] copper foil, and is formed by extending from the circuit wiring pattern for connecting the drive IC 19, etc., and its tips are extended as 14 connection wiring terminals 21a for connecting between adjacent circuit wiring boards 18. The circuit wiring terminal 21 and an insulating protective layer 22 made of a polyimide film with a thickness of 25 [μffl], which covers the circuit wiring terminal 21 on the circuit wiring portion 20b of the base 20 and protects the surface of the circuit wiring terminal 21.
The border of this protective layer 22 is the circuit wiring part 20b.
and the conductor connection portion 20a.

In the circuit wiring portion 20b of the base 20, the circuit wiring terminals 21 have a width of 0.5 mm and an interval (g
) is 0.3 mm, and in the conductor connection portion 20a of the base 2o, the connection wiring terminal 21a has a length of 4 mm from the circuit wiring portion 20b, and has the same width and the same spacing as the circuit wiring terminal 21. However, the length up to the base end of the conductor connection part 20a beyond that is 0.5 [
For 1 Ill, the width is 0.2 [m+el], and the interval (g') is 0.8 [mml].

Further, the connection wiring terminals 21a which are not covered with the insulating protective layer 22 and are exposed are plated with gold.

The circuit wiring board 18 configured in this manner is bent so that the conductor connecting portions 20a of adjacent boards are aligned so as to butt each other around the liquid crystal display panel 17a.

On the other hand, reference numeral 23 shown in FIG. 4 is a connection connector, which consists of a connector conductor part 24 made of parallel steel foil wires arranged at the same pitch as the connection wiring terminals 21a, and a connector connection part 26 made of polyimide film.

Note that 25 is solder.

Therefore, when manufacturing the liquid crystal display device 17, the liquid crystal display panel 1
Circuit wiring boards 18 are conductively connected to the four sides of 7a, and then adjacent circuit wiring boards 18 are bent so that their conductor connection parts 20a abut against each other with a gap (s) between them, and both of the abutted conductors Connecting portion 20a and connector connecting portion 26
After stacking the connecting connectors 23 so that they are in contact with each other, the connecting wiring terminal 21a and the connector conductor part 24 are connected with solder 25, and the circuit wiring to be wired to the drive (drive) C19 or passive components (not shown) is connected. The substrate 18 completes the connection between the liquid crystal display panel 17a and the driving IC 19.

With this configuration, the circuit wiring portion 2 of the circuit wiring board 18
0b, the interval (g) between the circuit wiring terminals 21 is set narrower than the width of the circuit wiring terminals 21, so that the high density of the circuit wiring portion 20b is not impaired, and the size of the circuit wiring board is reduced. In addition to being able to maintain weight reduction, the circuit wiring board 18
At the end of the conductor connection part 20a, the connection wiring terminal 2
Since the interval (g-) between 1a is set wider than the width of the connection wiring terminal 21a, when connecting adjacent circuit wiring boards 18, the butting positions may be slightly shifted, and the edge of the circuit wiring board 18 base may be slightly shifted. Even if the connecting wiring terminals 21a are in contact and the connecting wiring terminals are misaligned, the spacing (g') between the connecting wiring terminals 21a is as wide as 0.8 [w], so if there is a slight misalignment, the difference will occur as shown in Fig. 6. As shown in FIG. 2, the risk of short-circuiting with other connection wiring terminals is significantly reduced compared to the conventional method, and circuit malfunctions can be prevented without requiring high precision for alignment. electrical connections are made easier,
Yield during manufacturing is also improved.

If the conductor connecting portions 20a of the circuit wiring board 18 are slightly shifted during alignment as shown in FIG. 6, then as shown in FIG. The connection wiring terminals to be connected may be soldered together.

Next, a second embodiment of the present invention will be described with reference to FIGS. 8 and 9.

FIG. 8 is a diagram showing a first circuit wiring board 27 used for electronic components such as OA equipment and LCD televisions, and has a thickness of 25 [
The first base 28 is made of a polyimide film with a thickness of 18 [μm] and has a first conductor connection portion 28a and a first circuit wiring portion 28b formed thereon. The extended first circuit wiring terminals 30 are wired to have a wider width than the mutual spacing. In addition, a first connection wiring terminal 30a whose tip has a narrower line width than the circuit wiring terminal for connecting to an adjacent circuit wiring board
will be established. Furthermore, the first circuit wiring section 2 of the first base 28
8b, a first layer made of a polyimide film with a thickness of 25 [μl] is disposed on the first connection wiring terminal 30 to protect the first connection wiring terminal 30.
An insulating protective layer 31 is coated thereon.

The first edge 31a of the first insulating protective layer 31 avoids the portion of the first connection wiring terminal 30a that must be exposed for connection to an adjacent circuit wiring board. First connection wiring terminal 30a of conductor connection portion 28a
It is formed in an uneven shape so as to extend into the gap (1) between the two.

FIG. 9 also shows a first circuit wiring board 27 and a second circuit wiring board 27 having a conductor connection portion having the same shape as the first circuit wiring board 27.
33 is a second base, 34 is a second circuit wiring terminal having a second connection wiring terminal 34a, and 3B is a second circuit wiring terminal having a second connection wiring terminal 34a.
It is an insulating protective layer.

Moreover, 37 is a solder that electrically connects the first connection wiring terminal 30a and the second connection wiring terminal 34a.

Here, the second circuit wiring board 32 also serves as a connection connector, and is directly superimposed on the first circuit wiring board.

That is, when connecting adjacent circuit wiring boards, the first connection wiring terminal 30a and the second connection wiring terminal 34a to be connected, respectively, of the first circuit wiring board 27 and the second circuit wiring board 32 are made to face each other. After that, both corresponding connection wiring terminals are electrically connected with solder 37.

With this configuration, the uneven linear edges of the insulating protective layer will prevent each connection wiring terminal 30a from being damaged even if excessive force is applied after the two circuit wiring boards 27, 32 are connected.

The insulating protective layers 31.3B extend in the gaps (1) between the insulating protective layers 31.3B and the uneven portions support the bases of these portions against stress, so that stress is not applied to the ends of the insulating protective layers as in the conventional case. The circuit wiring board is strengthened at the boundary between the circuit wiring part and the conductor connection part without being concentrated, and bending thereof is prevented.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be modified in various ways, such as the width of the circuit wiring terminals or the spacing between the circuit wiring terminals. not only connects the circuit wiring boards, but also connects the first
As in the first modification shown in Figure 0, the circuit wiring board 18 is stacked on the inflexible circuit wiring board 38 and electrically connected via a connector (not shown). Connection between flexible substrates is also possible.

However, in this case as well, the connection wiring terminals are not in contact with each other at the connection part, and the connection wiring terminals 38 of the circuit wiring board 38
Even if the position of the connection wiring terminal 18a of the circuit wiring board 18 and the connection wiring terminal 18a of the circuit wiring board 18 is misaligned, a short circuit with other connection wiring terminals will not occur. In conventional circuit wiring boards, since the spacing between the connection wiring terminals at the connection part is narrow, the solder that flows through the connection part during soldering through the connection connector may cause short circuits with other connection wiring terminals. However, according to the circuit wiring board 18 of this modified example, even if solder flows to the connection part, the spacing between the connection wiring terminals is wide, so that circuit malfunction due to short circuit is prevented. It can be prevented.

Also in the second embodiment, the shape of the insulating protective layer extending in the gap between the connection wiring terminals can be arbitrary.
1, the tip 41a of the insulating protective layer 41 covering the circuit wiring terminal 40 is
2 to expose the semicircular shape, or the 12th
As in the third modified example shown in the figure, the tip 43a of the insulating protective layer 43 covering the circuit wiring terminal 40 may be made triangular.

Furthermore, in the second embodiment, for example, the interval between the tips of the first connection wiring terminals 30a of the first circuit wiring board 27 and the interval between the tips of the second connection wiring terminals 34a of the second circuit wiring board 32 are set as follows. As in the embodiment 1, the connection wiring terminal 30a
, 34a, even if some solder 37 flows when connecting adjacent circuit wiring boards, there is no risk of short-circuiting with different connection wiring terminals, resulting in more reliable circuit wiring. A substrate can be obtained.

Furthermore, the devices manufactured using the various circuit wiring boards described above are not limited, and may be video, office automation equipment, or the like.

Furthermore, when connecting each circuit wiring board, a connecting connector may or may not be used.

[Effects of the Invention] As explained above, according to the present invention, the high density of the circuit wiring board is not impaired, the size and weight of the circuit wiring board is maintained, and the positioning of the circuit wiring board is not required as in the conventional method. Therefore, there is no need for high accuracy, and when connecting circuit wiring boards,
Since short circuits of circuit wiring terminals can be easily prevented, circuit malfunctions can be prevented, electrical connections between circuit wiring boards can be easily made, and manufacturing yields can also be improved.

In addition, even if force is applied to the connection part after the circuit wiring board is connected, the stress will not be concentrated at the edge boundary of the insulating protective layer as in the conventional case, so the circuit wiring board will not be bent, making it reliable. It is possible to obtain a circuit wiring board with high performance.

[Brief explanation of the drawing]

1 to 7 show a first embodiment of the present invention, FIG. 1 is a schematic plan view of a liquid crystal display device using the circuit wiring board device, and FIG. 2 is a part of the circuit wiring board. An enlarged view, FIG. 3 is a partial plan view showing the state in which the adjacent circuit wiring boards are butted together, FIG. 4 is a partial plan view showing the state in which the adjacent circuit wiring boards are connected, and FIG. A-A in Figure 4
6 is a partial plan view showing a state in which the positions of adjacent circuit wiring boards are shifted, and FIG. 7 is a sectional view taken along the line.
The figure is a partial plan view showing the state in which the circuit wiring board shown in FIG. 6 is connected, and FIGS. 8 and 9 show a second embodiment of the present invention, and FIG. Part (a) is a plan view, (b) is a cross-sectional view, Figure 9 is a partial cross-sectional view showing the state in which adjacent circuit wiring boards are soldered together,
Figure 0 is a partial plan view showing the first modification of the present invention;
12 is a partial plan view showing a third modification example of the present invention, and FIGS. 13 to 17 show a conventional device. Fig. 13 is a schematic plan view showing the connection between the circuit wiring board and the liquid crystal display panel, Fig. 14 is a partial plan view showing the state in which the adjacent circuit wiring boards are butted together, and Fig. 15 shows the adjacent circuits. FIG. 16 is a partial plan view showing a state in which the wiring boards are connected; FIG. 16 is a partial plan view showing a state in which adjacent circuit wiring boards are shifted;
FIG. 7 is a partial cross-sectional view showing a state in which the adjacent circuit wiring boards are connected facing each other, and FIG. 18 is a partial cross-sectional view showing a state in which the circuit wiring boards in FIG. 17 are folded. 17a...Liquid crystal display panel, 18...Circuit wiring board, 20...Base, 2
0a... Conductor connection part, 20b... Circuit wiring part, 21... Circuit wiring terminal, 21a... Connection wiring terminal, 22... Insulation protection layer, 23... Connection connector, 27...・First circuit wiring board, 28... First base, 30... First connection wiring terminal, 31... First insulation protective layer, 32... Second circuit wiring board, 33... Second base, 34... Second connection wiring terminal, 36... Second insulating protective layer. Agent Patent Attorney Nori Ogo

Claims (3)

[Claims] (1) Consisting of a flexible base, a plurality of circuit wiring terminals provided on the base at predetermined intervals and having a width wider than this interval, and a plurality of connection wiring terminals extending from these circuit wiring terminals to the end of the base. A first circuit wiring board, a flexible base, a plurality of circuit wiring terminals provided on the base at predetermined intervals and having a width wider than the intervals, and a plurality of connections extending from the circuit wiring terminals to the end of the base. a second circuit wiring board comprising a wiring terminal and installed adjacent to the base end of the first circuit wiring board so that its base end abuts against the base end of the first circuit wiring board; and the first and second circuit wiring boards. In the circuit wiring board, the connection wiring terminals of the first and second circuit wiring boards are connected to the circuit wiring terminals and the spacing thereof at least at the base end. A circuit wiring board device characterized in that the width is narrower than the width. (2) The circuit wiring board device according to claim (1), wherein the connecting portion of one of the connecting wiring terminals of the first and second circuit wiring boards also serves as a connecting connector and is overlapped with the connecting portion of the other connecting wiring terminal. . (3) The circuit wiring terminal is covered with an insulating protective layer, and the connecting wiring terminal is exposed and extended from the edge of the insulating protective layer, and the edge of the insulating protective layer is covered with the circuit wiring terminal and the connecting wiring terminal. 3. The circuit wiring board device according to claim 1, wherein the circuit wiring board device has an uneven line shape extending across the gap.