JP2894034B2 - Cross wiring method for flexible printed wiring boards - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cross-wiring a flexible printed wiring board used as a wiring material for automobiles, for example.

[0002]

2. Description of the Related Art A circuit design of a flexible printed wiring board is performed using a wiring diagram represented by a plurality of wirings 1 as shown in FIG. 20, for example. In this case, as shown in the wiring diagram, for example, when it is necessary to electrically connect the wirings 1a and 1c on both sides of the wiring 1b, only a planar wiring pattern can be formed with a single-layer flexible printed wiring board. , The cross wiring portion is an obstacle. Therefore, such a case is generally handled by using a jumper wire.

FIG. 21 is a plan view showing a conventional flexible printed wiring board 10 prepared based on the wiring diagram of FIG. 20, and FIG. 22 is a sectional view taken along line AA of FIG. As shown in both figures, the flexible printed wiring board 10
A base film, a plurality of wirings formed on the base film, and an overlay film joined to the base film via an adhesive layer so as to cover the plurality of wirings; I have. In this case, the wirings 20, 21, 22, 23 in FIG. 21 correspond to the wirings 1, 1a, 1b, 1c in FIG. 20, respectively, and wirings 21, 23 are formed on both sides of the wiring 22.

[0004] Such a flexible printed wiring board 1
In FIG. 22, as shown in FIG. 22, a region corresponding to a part of each of the wirings 21 and 23 of the overlay film 14 is removed, and a part of each of the wirings 21 and 23 and a base film of a region corresponding thereto are removed. 11, a jumper wire mounting hole 17 penetrating in the up-down direction is formed. Then, the jumper wires 18 are respectively inserted into the jumper wire mounting holes 17 and fixed by the solder 19. Thus, the wirings 21 and 23 are electrically connected to each other to form a cross wiring.

[0005]

However, the conventional cross wiring method described above has a problem that the productivity is low because the soldering of the jumper wires 18 is performed manually. In this case, soldering can be automated by using reflow soldering and flow soldering. However, since the PET film constituting the flexible printed wiring board 10 generally has low heat resistance, reflow soldering and flow soldering involving high temperatures are required. Soldering is not applicable.

Further, since the cross wiring between the wirings 21 and 23 is performed via the jumper wire 18, when the device is used in a place where vibrations are severe and a change in cooling and heating is large like an automobile, for example, the solder connecting portion of the jumper wire 18 is used. There is a problem that solder cracks and the like occur and the connection reliability at these connection portions is poor.

Further, since the PET film has low heat resistance as described above, there has been a problem that the heat generated at the time of soldering causes the flexible printed wiring board 10 to be thermally deteriorated and the yield to be deteriorated.

The present invention solves the above-mentioned problems of the prior art, makes it easy to perform cross wiring work, has excellent reliability of connecting portions, and can improve the yield and productivity of flexible printed wiring boards. An object is to provide a wiring method.

[0009]

SUMMARY OF THE INVENTION claims 1 invention, electricity in the flexible printed wiring board having a plurality of wirings coated with which the film is arranged in parallel, the wiring to other wiring other than the wiring of the adjacent a cross line method for connecting, in order to achieve the above object, in between the other lines and the one wiring, non-wiring region between said first wiring and said adjacent wiring , and the non-wiring region between said other wiring <br/> and the neighboring wiring, each of the distribution
Forming first and second cuts substantially parallel to the line ;
Of the three regions separated by the first and second cuts, the regions on both sides are drawn together and overlapped,
At the overlapping portion, the one wiring and the other wiring are electrically connected to each other.

[0010] The second aspect of the present invention, in the flexible printed wiring board having a plurality of wirings coated with which the film is arranged in parallel, and electrically connects the first wiring to the other wiring other than the wiring of the adjacent a cross wiring methods, in order to achieve the above object, the one wiring and the other
The non-wiring area between the wiring, substantially parallel to the wire
A cut portion having a closed end at both ends is formed, and the two regions separated by the cut portion are attracted to each other and overlapped, and the one wire and the other wire are electrically connected to each other at the overlap portion. Connected to

[0011]

In the method for cross-wiring a flexible printed wiring board according to the first aspect, first and second cut portions are formed, and regions on both sides of the three separated regions are drawn toward each other and overlapped. combined, only mutually electrically connects one wiring disposed on both sides of the region and the other wiring <br/> at its overlap portion, it can be easily realized cross wires, the conventional cumbersome The soldering work of a jumper wire can be omitted.

Further, in the method for cross-wiring a flexible printed wiring board according to the second aspect of the present invention, a cut portion having a closed end at both ends is formed, and the two regions separated by this are attracted to each other and overlapped, and the overlap is performed. an wiring and are disposed, respectively and another wiring on both regions in the parts mutually only electrically connecting the cross wire easily realized, can be omitted soldering of conventional jumper wire.

[0013]

FIG. 1 shows a flexible printed wiring board used in a first embodiment of the present invention, which is designed in accordance with the wiring diagram of FIG. 2 is a cross-sectional view of a main part of the wiring board 50, and FIG. 3 is an enlarged plan view of a main part of FIG.

The basic sectional structure of the flexible printed wiring board 50 used in this embodiment is the same as that of the above-mentioned conventional example. As shown in FIG. 2, a base film 41 and an adhesive layer 42a are formed on the base film 41. a plurality of wirings 60 formed through, and an overlay which is bonded via the adhesive layer 42b so as to cover the plurality of wiring 60 on the base film 41 film 43. Further FIG.
As shown in the wiring structure of the flexible printed circuit board 50 is also substantially the same as the conventional example, the wiring 61, 62, 63
Are formed substantially parallel and continuously to each other, but the area where the cross wiring is formed (hereinafter referred to as “cross wiring area”) is the conventional flexible printed wiring board 1 of FIG.
It is slightly different from 0.

That is, a film area between the wirings 61 and 62 and a film area between the wirings 62 and 63 are formed to be wide, respectively.
Connection wires 61a extending from the wires 61 and 63, respectively.
63a are formed.

In FIG. 1, wires 60, 61, 6
Reference numerals 2, 63 correspond to the wirings 1, 1a, 1b, 1c in FIG.

Such a flexible printed wiring board 5
In order to perform the cross wiring between the wirings 61 and 63 using the “0”, a non-wiring area (film area) between the wirings 61 and 62 and the wirings 62 and 63 in the cross wiring area as shown in FIGS. A non-wiring area (film area) between the first and second slits 63 is cut by a predetermined amount along the wirings 61 and 63 to form first and second cut portions 71 and 72. Second cut 7
1 and 72 and the first and second cuts 7
1 and 72 are separated into regions 81 and 82 on both sides.

Next, as shown in FIG.
1 and 82 are attracted to each other so that the connection wiring 63a in the other area 82 corresponds to the connection wiring 61a in the one area 81 (see FIG. 3).
2 are superimposed on each other. In this case, in FIG. 4, the region 82 is arranged above, but either of the regions 81 and 82 may be arranged above, and the vertical relationship does not matter. Further, the two regions 81 and 82 may be overlapped at a position above the central region 80.

Thereafter, as shown in FIG. 5, the rivet terminal 90 is connected to both connection wirings 61a, 63 of both regions 81, 82.
a so as to penetrate each of the two regions 81, 8
2 and the connection wires 61a, 63
Electrical connection between a is also planned. In this case, for both connections
In order to further increase the electrical connection between the wires 61a and 63a, the overlay film 43 in a region corresponding to the connection wire 61a in one region 81 is removed in advance, and the overlay film 43 corresponding to the connection wire 63a in the other region 82 is removed. The base film 41 in the region is removed in advance to expose both connection wirings 61a and 63a.
The rivet terminal 90 may be attached in a state where the wirings 61a and 63a are directly overlapped.

[0020] Thus, distribution arranged on both sides of the wiring 62
A cross wiring in which the lines 61 and 63 are electrically connected to each other is formed.

According to the method for cross-wiring a flexible printed wiring board, the first and second cut portions 71 and 72 are provided.
And three regions 80, 8 separated thereby.
1, 82, the regions 81, 82 on both sides are drawn toward each other and overlapped, and the regions 81, 82 on both sides are pulled by the rivet terminal 90.
Cross-wiring can be easily realized simply by connecting the interconnections to each other, and a complicated connection operation of jumper wires can be omitted, so that productivity is improved.

Further, the regions 81 and 82 on both sides are directly overlapped with each other, and wirings 61 and 63 (for connection) are connected by rivet terminals 90.
Since the electrical connection between the wirings 61a and 63a) is made, sufficient connection reliability with these connecting wirings can be obtained. Moreover, since no jumper wire is used, there is no need to solder the jumper wire, and even when this flexible wiring board 50 is used in an automobile or the like where the vibration is intense and the temperature change is large, there is no need to consider solder cracks. Also in this regard, the connection reliability of the connection portion is improved.

Further, since the soldering process is not required, the deterioration of the flexible printed wiring board 50 due to the heat generated at the time of soldering is prevented, and the yield is improved.

In the above embodiment, the first and second cut portions 71 and 72 are formed so as to cut the non-wiring region (film region). The first and second cut portions 71 and 72 may be formed as shown in FIG.

As shown in FIG. 7, slits 71a and 71a are formed in a region where the first and second cut portions are to be formed.
Flexible printed wiring board 50a on which 72a is formed
Alternatively, as shown in FIG. 8, a flexible printed wiring board 50b having a plurality of holes 71b and 72b intermittently arranged on a straight line is prepared in advance, and the perforated slits 71a and 72a or straight lines are formed. Multiple holes 71
The first and second cuts may be formed by tearing the film area along b and 72b, respectively.

In the above embodiment, the connection wiring 61
Although a and 63a are formed linearly (see FIG. 3), they may be formed in other shapes. For example, as shown in FIG. 9, the connection wires 61a and 63a may be formed in a T shape, or may be formed in an L shape in FIG. 10 or a U shape in FIG. However, as shown in FIG. 12, the connection wiring 61
a, 63a may be omitted, and a part of the wirings 61, 63 may be overlapped with each other to be electrically connected.

In the above embodiment, the regions 81 on both sides,
Although the rivet terminals 90 are used to connect the 82s to each other, other connecting means may be used. For example, FIG.
As shown in FIG.
May be connected. In this case, as shown in FIGS. 13 and 14, the base film 41 in the lower region 81 is compressed by crimping the crimp terminal 91 so that the crimp terminal 91 is formed.
Pierced by the insulating film removal lance 91a of
The caulking terminal 91 and the connection wiring 63a in the lower region 81 are electrically connected. Further, by curling the leg pieces 91b of the caulking terminal 91 inward,
The overlay film 43 in the upper area 82 is
b breaks through, and the connection wiring 61a in the upper region 82 and the caulking terminal 91 are electrically connected. Thus, the connection wirings 61 a and 63 a are electrically connected via the caulking terminal 91.

As another connection method, the lower region 8
The first overlay film 43 and the base film 41 in the upper region 82 are removed in advance in the process of manufacturing the wiring board 50, and the two connection wirings 61a and 63a are connected by ultrasonic welding in a state where they are in contact with each other. Alternatively, the connection wires 61a and 63a may be connected by a conductive adhesive.

Further, in the above embodiment, the overlay film 43 side of the lower region 81 and the base film 41 side of the upper region 82 are overlapped. May be superimposed. For example, as shown in FIG. 15, the overlay films 43 in the regions 81 and 82 on both sides may be removed in advance, and the connection wires 61a and 63a may be connected to each other by ultrasonic welding. As further shown in FIG. 16 in this case, wiring both connection 6
17a and 63a may be connected by a conductive adhesive 92, or may be connected by a clip 94 via an anisotropic conductive rubber 93 as shown in FIG. In addition, it is of course possible to connect with a caulking terminal or a rivet terminal.

Further, the base films 41 of the two regions 81 and 82 may be connected so as to overlap each other.

<Second Embodiment> FIG. 18 is a plan view of a main part of a flexible printed wiring board 150 used in a second embodiment according to the second aspect of the present invention. The flexible printed wiring board 150 used in this embodiment has the same configuration as the flexible printed wiring board 50 of the first embodiment.

Firstly, the cross wire method according to this embodiment, as shown in FIG. 18, the non-wiring region between lines 162 and 163 (film area), both ends closed shape predetermined amount slitting along the lines 162 and 163 forming a switching cleft 170, thereby cross wiring region of the two regions 181,1
Separated into 82.

Next, as shown in FIG.
1, 182 are attracted to each other, and the connection wirings 161a, 1
63a correspond to each other so that both regions 181, 18
Overlap 2. In this case, either of the two regions 181 and 182 may be arranged on the upper side, and the upper and lower relation is not particular.

After that, as in the first embodiment, the rivet terminal 90 is crimped to mechanically connect the two regions 181 and 182, and the electrical connection between the two connecting wires 161a and 163a is made, and the cross wiring is made. To form

Also in this method of cross-wiring the flexible printed wiring board, since the two regions 181 and 182 are directly overlapped with each other to establish electrical connection between the wirings 161 and 163, sufficient connection reliability at the connection portion is obtained. Since it can be secured and the soldering process is not required, the thermal deterioration of the flexible printed wiring board 150 is prevented, and the yield is improved.

The non-wiring area between the wirings 161 and 163
In addition, a cutout 170 having a closed end at both ends is formed.
The two separated areas are attracted to each other and overlap,
Wiring respectively arranged in both areas at the overlapping part of
Since the electrical connection between 161a and 163a is made,
In the middle of the wirings 161 and 163 extending in parallel,
61 and 163 can be cross-wired.

Further, in this method, since the cross wiring can be formed only by forming the cut portion 170 at one place, the cross wiring can be more easily realized as compared with the first embodiment.

In the second embodiment, the same modifications (see FIGS. 6 to 17) as in the first embodiment can be applied.

[0039]

As described above, according to the cross wiring method for a flexible printed wiring board according to the first aspect, the first and second cut portions are formed, and among the three film regions separated thereby, superimposed attract both sides of the region to each other, only mutually electrically connects one wiring disposed on both sides of the region and the other wirings in the overlap portion, you can achieve cross line, Since the complicated soldering work of the jumper wire can be omitted, the productivity is improved. In addition, since the wiring is directly electrically connected to each other without using a jumper wire or the like, the connection reliability of these connection portions is improved, and the thermal deterioration of the flexible printed wiring board due to heat during soldering is performed. Is prevented and the yield is improved.

According to the cross-wiring method for a flexible printed wiring board of the present invention, a cut portion having a closed end at both ends is formed, and the two film regions separated by this are attracted to each other and overlapped, and the overlap is performed. each can be realized in the middle <br/> cross line of one wiring is disposed and another wiring and mutually pair of wires extending in parallel by only electrically connecting both regions in the parts, the claim The same effect as the method 1 can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view showing a flexible printed wiring board used in a cross wiring method according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the flexible printed wiring board.

FIG. 3 is an enlarged plan view of a main part of FIG. 1;

FIG. 4 is a perspective view for explaining a cross wiring method according to the first embodiment.

FIG. 5 is a cross-sectional view for explaining the cross wiring method of the first embodiment.

FIG. 6 is a plan view of a principal part for describing a modification of the present invention.

FIG. 7 is a plan view of a main part for describing a modification of the present invention.

FIG. 8 is a plan view of relevant parts for describing a modification of the present invention.

FIG. 9 is a plan view of relevant parts for describing a modification of the present invention.

FIG. 10 is a plan view of relevant parts for describing a modification of the present invention.

FIG. 11 is a plan view of relevant parts for describing a modification of the present invention.

FIG. 12 is a main part plan view for explaining a modification of the present invention.

FIG. 13 is a cross-sectional view of a main part for describing a modification of the present invention.

FIG. 14 is a partially cutaway perspective view showing a caulking terminal used in the modification of FIG.

FIG. 15 is a cross-sectional view of a main part for describing a modification of the present invention.

FIG. 16 is a cross-sectional view of a main part for describing a modification of the present invention.

FIG. 17 is a cross-sectional view of a main part for describing a modification of the present invention.

FIG. 18 is a plan view of a principal part showing a flexible printed wiring board used in a cross wiring method according to a second embodiment of the present invention.

FIG. 19 is a perspective view illustrating a cross wiring method according to the second embodiment.

FIG. 20 is a wiring diagram of a flexible printed wiring board.

FIG. 21 is a plan view of a flexible printed wiring board to which a conventional cross wiring method is applied.

FIG. 22 is a sectional view taken along line AA of FIG. 20;

[Explanation of symbols]

41 Base film 43 Overlay film 50,150 Flexible printed wiring board 60,61-63,160,161-163 Wiring 71,72,170 Cut part 80,81,82,181,182 Area

Claims (2)

(57) [Claims] 1. A flexible printed wiring board having a plurality of wirings coated with arranged in parallel film, cross Wiring for electrically connecting the first wiring to the other wiring other than the wiring of the adjacent a is, in between the other lines and the one wiring, the one
Non-wiring region, and the non-wiring region between said other wiring and the neighboring wiring, substantially parallel first and second switching cleft to the wiring respectively between the wiring and the neighboring wiring to form a, overlay attracted to each other on both sides of the region of the first and three regions separated by a second switching cleft, the other and the one wiring in the overlap portion
Cross wire method of a flexible printed wiring board, characterized by electrically connecting the wiring to each other. 2. A flexible printed wiring board having a plurality of wirings coated with arranged in parallel film, cross Wiring for electrically connecting the first wiring to the other wiring other than the wiring of the adjacent a is, in the non-wiring region between the one wiring and another wiring, the distribution
The two closed ends shaped switching cleft formed substantially parallel to the line, the switching cleft by overlay attracted to each other two areas separated, the other lines and the one wiring in the overlap portion And a cross-wiring method for a flexible printed wiring board.