JP2923522B2 - Flexible wiring board and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible wiring board (FPC) used for instruments such as automobiles and a method of manufacturing the same. The present invention relates to a flexible wiring board mounted on an instrument case having a recess, particularly an instrument case having a concave portion in which electronic components are concentrated and wiring is difficult to pass, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Usually, a flexible printed circuit (FPC)
Is a flexible thin substrate on which a plurality of electric circuits are formed. That is, a flexible wiring board in which a circuit for conducting between components is formed on a flexible substrate before mounting electronic components or the like on the instrument case is attached to a predetermined position on the case. Thereafter, a light emitting diode (LED) for display of instruments and the like is mounted on the flexible wiring board at a predetermined position on the case. Therefore, even if there is a stepped uneven portion on the mounting surface on the instrument case, the flexible wiring board to be attached can be bent freely, so that the wiring step can be performed collectively with one flexible wiring board.

[0003] As an example of the use of a conventional full Rekishiburu wiring board, illustrating a conventional example using the meter portion of the automobile in FIGS. 4-8. FIG. 4 is a partial perspective view showing the shape of a main part of an instrument panel of an automobile. A resin case body 100 has a substantially flat meter panel 10 on its front surface.
1 is formed, and the back surface 102 is provided with a step-like uneven portion. The meter panel 101 is divided into three regions, and a first region 101a is provided with a fuel meter for displaying the remaining amount of gasoline, the temperature, and the like. In the second area 101b, a display plate indicating the position of the shift lever, that is, the state of the transmission is arranged. Further, a speedometer is arranged in the third area 101c.

As shown in FIG. 5, a first mounting surface 102a, a second mounting surface 102b, and a third mounting surface 1b corresponding to the respective regions are formed on the back surface 102 of the case body 100.
02c is formed. The flexible wiring board 103 is configured to be mounted on the mounting surface with screws or the like. This flexible wiring board 103 has wiring circuit surfaces 103a, 103b, 103c corresponding to the three mounting surfaces 102a, 102b, 102c of the case body 100, respectively.
It is formed integrally with the bent part 110. The bent portion 110 is provided on the mounting surface 102 of the concave portion of the case body 100.
When the wiring circuit surface 103b is mounted on the vertical wall b, it is mounted on the vertical walls at both ends of the concave portion. In addition, mounting holes 104 for mounting a plurality of electronic components such as LEDs are formed on the flexible wiring board 103.

When the flexible wiring board 103 is mounted on the back surface 102 of the case main body 100, both sides of the second circuit surface 103b corresponding to the second mounting surface 102b, which is a concave portion, are bent in a concave shape by the bent portion 110. Can be In this state, the flexible wiring board 103 is
6 is attached to the back surface 102 of FIG.

Although not shown, the first circuit surface 103a and the third circuit surface 103 of the flexible wiring board 103 are not shown.
Since electronic components other than LEDs are arranged in c,
In many cases, conduction between the first circuit surface 103a and the third circuit surface 103c is required. However, LE on the second circuit surface 103b
Since D is arranged in a close state, the first circuit surface 103
A conductive circuit that connects the second circuit surface 103a to the third circuit surface 103c cannot be formed on the second circuit surface 103b.

[0007] Therefore, as shown in FIG.
Wiring means is provided for passing a plurality of jumper wires 105 between the third circuit surface 103a and the third circuit surface 103c to make them conductive. As another wiring means, a second flexible wiring board 106 different from the flexible wiring board 103 in which the mounting holes 104 are arranged as shown in FIG. 8 is arranged on the flexible wiring board 103. As a result, the first circuit surface 103a and the third circuit surface 103c are conducted by the bridge portion 106a of the second flexible wiring board 106.

[0008]

However, the above-mentioned jumper wire 105 or the second flexible wiring board 1
Use of 06 increases the number of parts, leading to an increase in cost and a reduction in work efficiency.

Further, since the flexible wiring board 103 is bent in conformity with the shape of the back surface 102 of the case body 100, the flexible wiring board 103 is
3 itself may be warped. That is, the bent portion is not bent at a right angle but is mounted in a slightly rounded state, which is different from the designed size.

Thus, even when the mounting hole 104 of the flexible wiring board 103 is aligned with the LED mounting hole of the case body 100 and mounted, the flexible wiring board 1
Since the bent dimension of the circuit board 03 is different from the design, the attached flexible wiring board 103 is bent. Due to the bending of the flexible wiring board 103, even if the above-mentioned jumper wire 105 is used, the mounting position is changed, and the working efficiency is further deteriorated. In addition, even if the second flexible wiring board 106 is used, it cannot be mounted accurately, so that the yield as a product has deteriorated.

The object of the present invention has been made in view of the above-mentioned problems, and the wiring of a flexible wiring board to a case body having a step-like uneven surface on which electronic components and the like are arranged in close contact with each other is described. It is an object of the present invention to provide a highly reliable flexible wiring board which is performed without increasing the number of parts and without wasting cost, and a method for manufacturing the same.

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flexible circuit having a plurality of circuit surfaces mounted in a case having a stepped concave or convex portion in which electronic components are concentrated and wiring is difficult to pass through. In the wiring board, a first circuit surface formed on the flexible wiring board, a second circuit surface arranged in the concave portion or the convex portion where electronic components are concentrated, and a position facing the first circuit surface. A third circuit surface formed on
The extended from the first circuit face, Bei a branch wiring board which is electrically connected to the third circuit surface while bypassing the recesses or protrusions
The free end of the branch wiring board is brought into contact with the case.
Connection part provided at a predetermined position on the third circuit surface in a state in which
A connected portion that is conductively connected to the
The connected portion is aligned with the connection portion on the third circuit surface.
Are formed so as to be shifted by a predetermined length in the longitudinal direction .

[0013]

Another object of the present invention is to provide a method of manufacturing a flexible wiring board having a plurality of circuit surfaces to be mounted in a case having a stepped concave portion or a convex portion in which electronic components are concentrated and wiring is difficult to pass. In the above, by punching a single flexible wiring board, a first circuit surface, a second circuit surface extending from the first circuit surface and disposed in the concave portion or the convex portion, and further from the second circuit surface An extended third circuit surface, and a connected portion extending from the first circuit surface and bypassing the second circuit surface and electrically connected to a connection portion provided at a predetermined position on the third circuit surface. A branch wiring board with
A notch recess is formed in the flexible wiring board at the same time as the punching, and the connected part extending to the inside of the notch recess is formed.

[0015] Further, the object is that the connected part is the third part.
This can be achieved more effectively because the connected parts are formed so as to be shifted by a predetermined length along the longitudinal direction so as to coincide with the connection parts on the circuit surface.

[0016]

In the flexible wiring board having the above-mentioned structure according to the present invention, the first circuit surface formed on the flexible wiring board and the second circuit surface disposed on the concave portion or the convex portion where the electronic components are concentrated. A third circuit surface formed at a position facing the first circuit surface; a branch wiring board extending from the first circuit surface and electrically connected to the third circuit surface bypassing the concave or convex portion; And a cable at a free end of the branch wiring board.
Provided at a predetermined position on the third circuit surface in contact with the
A connected portion that is electrically connected to the connected portion is provided;
So that the connection points coincide with the connection points on the third circuit surface
The connected part is shifted by a predetermined length in the longitudinal direction.
It has been formed. Further, in the method for manufacturing a flexible wiring board according to the present invention, the one circuit board is punched out, and the first circuit surface and the first circuit surface are extended from the first circuit surface and arranged in the concave portion or the convex portion. A second circuit surface; a third circuit surface extending from the second circuit surface;
A branch wiring board having a connected portion extending from the circuit surface and bypassing the second circuit surface and electrically connected to a connection portion provided at a predetermined position on the third circuit surface is formed; At the same time as the punching, a notch recess is formed in the flexible wiring board, and the connected portion extending to the inside of the notch recess is formed.

Thus, first, the first circuit surface and the third circuit surface are mounted at predetermined positions on the case surface, and then a plurality of positions are aligned with the concave portions or convex portions so as to contact the concave portions or convex portions of the intermediate portion. The second circuit surface is mounted by bending. And
Finally, after the branch wiring board is mounted on the side surface of the case so as to bypass the second circuit surface of the concave portion or the convex portion, the connected portion provided at the end of the branch wiring board is fixed to a predetermined portion of the third circuit surface. It is conductively connected to a connection portion provided at the position. Therefore, the conductive connection between the first circuit surface and the third circuit surface is performed while the position is adjusted by the branch wiring board having the connected portion without using the second circuit surface mounted on the concave portion or the convex portion. For this reason, the conductive connection between the circuit surfaces on the flexible wiring board can be easily and reliably made at a predetermined position without being affected by bending of the wiring board.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the flexible wiring board of the present invention and a method for manufacturing the same will be described in detail with reference to FIGS. FIG. 1 is a perspective view showing a state in which a flexible wiring board according to one embodiment of the present invention is mounted on a case main body.
Is a plan view of the flexible wiring board in FIG. 1, and FIG. 3 is a perspective view showing a state in which the flexible wiring board of the present invention is mounted on a case body having another configuration. The same parts as those described in the related art are denoted by the same reference numerals, and description thereof is omitted.

First, as shown in FIG. 2, a flexible wiring board 13 of this embodiment has a mounting hole 14 for an electronic circuit or LED (not shown) formed on a back surface of a case body on a flexible sheet-like substrate. Plural arrangements are made corresponding to the mounted mounting surfaces. The flexible wiring board 13 has a first circuit surface 13a and a second circuit surface 13 corresponding to the back surface of the case body.
b, the third circuit surface 13 c is integrally connected by the first bent portion 19. The end of the first circuit surface 13 a is connected by a second bent portion 15, and a long branch wiring board 16 extends along the longitudinal direction of the flexible wiring board 13.

Then, from one end of the long side of the branch wiring board 16, the third bent portion 1 is directed toward the third circuit surface 13c.
A connected portion 18 which is a free end extends through the connection member 7. The connected portion 18 includes an electronic circuit (not shown) disposed on the first circuit surface 13a and a bypass circuit 21 connected to the LED.
Are formed. The third connected part 18
On the circuit surface 13c, a connection portion 20 that is connected to an electronic circuit or an LED is formed. In addition, the flexible wiring board 1
The bent portions 15, 17, and 19 of the third are mounted on a vertical wall portion forming a step portion or a concave portion of the case body.

The distal end of the connected portion 18 is formed by a notch recess 1 formed at a position facing the flexible wiring board 13.
9a. The position of the connected portion 18 in the cutout recess 19a is such that when the second circuit surface 13b of the flexible wiring board 13 is bent and mounted in the recess of the case main body, the connected portion 18 is positioned on the third circuit surface 13c. Connection part 2
It is arranged to match 0. That is, the connected part 1
8 is the second with respect to the connecting portion 20 on a straight line along the longitudinal direction.
They are arranged on the circuit surface 13b side by being shifted by a predetermined length (L).

The substrate of the flexible wiring board 13 of the present embodiment described above is stamped and formed from a long base material corresponding to the uneven back surface of the case body. Therefore, the connected portion 18 is substantially positioned at the connecting portion 20 on the third circuit surface 13c in a state where each bent portion of the flexible wiring board 13 is bent on the case body. Therefore, the degree of freedom in designing the flexible wiring board 13 is increased, and the flexible wiring board 13 can be designed to have a planar shape that minimizes useless base materials.

As shown in FIG. 1, the case body 1 has a substantially flat meter surface 11 formed on the front surface thereof.
On the meter surface 11, a display indicating the state of the shift lever is arranged together with a speedometer and a fuel meter. On the back surface 12 of the case main body 1, a projecting surface 2 provided in a step shape on which the branch wiring board 16 is arranged is formed.

Next, the flexible wiring board 13 of this embodiment
The procedure for attaching the case to the case body back surface 12 will be described in detail. First, the first circuit surface 13a of the flexible wiring board 13 is mounted on the first mounting surface 12a on the case back surface 12, and the third circuit surface 13c is mounted on the third mounting surface 12c. Next, the first bent portions 19 at both ends of the second circuit surface 13b are bent and attached to the second mounting surface 12b which is a concave portion. Next, the second bent portion 1 of the first circuit surface 13a
5 is bent so that the branch wiring board 16 is mounted on the overhanging surface 2. Then, the third bent portion 17 extended from the branch wiring board 16 is bent to lift the connected portion 18 to the third mounting surface 12c. In this state, the connected part 18 is electrically connected to the connecting part 20 formed at a predetermined position on the third circuit surface 13c by connecting means such as a screw or solder.

As a result, the electronic components and the like mounted on the first circuit surface 13a of the flexible wiring board 13 are moved from the first circuit surface 13a to the second bent portion 15, the branch wiring board 16, and the third bent portion 17 Is connected to the connecting portion 20 provided at a predetermined position on the third circuit surface 13c via the connected portion 18, and is electrically connected to electronic components and the like on the third circuit surface 13c.

Next, as a second embodiment of the present invention, a case where the flexible wiring board 13 is mounted on a case body having a different configuration will be described. As shown in FIG. 3, a portion of the case body 30 different from the above-described case is that the branch wiring board 16 is routed not along the overhanging surface 2 but along the side wall of the case body 30. Therefore, a locking portion 33 provided with a plurality of locking pieces 34 for holding the branch wiring board 16 is provided. The locking portion 33 extends along the side wall of the case body 30, and has a configuration in which the end portion of the branch wiring board 16 is sandwiched by a plurality of locking pieces 34.

The procedure for mounting the flexible wiring board 13 on the case main body 30 is as follows.
A first circuit surface 13a and a second circuit surface 13 corresponding to the mounting surface 32b and the third mounting surface 32c of the flexible wiring board 13, respectively.
b, the third circuit surface 13c is bent at the first bent portion 19 and mounted. And, unlike the above embodiment, the second
The bent portions 15a of the bent portion 15 and the third bent portion 17,
17a is bent only once. That is, the branch wiring board 16 extending from the second bent portion 15 to the third bent portion 17
Is flatly attached to the side wall of the case body 30. Further, the position of the connected portion 18 is adjusted on the third circuit surface 13c in the same manner as in the above embodiment, and is electrically connected by connecting means such as screws or solder. At this time, the end of the branch wiring board 16 is 3
The locking pieces 34 are locked to the case body 30.

[0028]

As described above, according to the flexible wiring board and the method of manufacturing the same of the present invention, the first circuit surface formed on the flexible wiring board and the concave portion or convex portion where the electronic components are concentrated are provided. A second circuit surface to be disposed; a third circuit surface formed at a position facing the first circuit surface; and a third circuit surface extending from the first circuit surface and bypassing the concave portion or the convex portion and conducting to the third circuit surface. and a branch wiring board to be connected, of the branch wiring board
At the free end, the third circuit surface is in contact with the case.
A connected part that is conductively connected to a connecting part provided at a predetermined position
Is provided, and the connected portion is connected to the connection portion on the third circuit surface.
The connected portion is a predetermined length along the longitudinal direction so as to match.
It is formed by shifting only . In addition, by punching one flexible wiring board, a first circuit surface and a second circuit extending from the first circuit surface and disposed in the concave portion or the convex portion are provided.
A circuit surface, a third circuit surface further extending from the second circuit surface, and a predetermined surface of the third circuit surface extending from the first circuit surface and bypassing the second circuit surface. A branched wiring board having a connected portion electrically connected to the connected portion, a cutout recess is formed in the flexible wiring board at the same time as the punching, and the connection extending to the inside of the cutout recess. A part is formed.

Therefore, since the conductive connection can be adjusted and adjusted so as to eliminate the dimensional error due to the bending of the flexible wiring board, separate components such as jumper wires are not required, and the cost can be reduced and the working efficiency can be improved. . In addition, since the flexible wiring board can be prevented from being bent by the branch wiring board, labor for mounting work due to the bending can be omitted, and work efficiency can be improved and yield can be prevented. Furthermore, since the detour of wiring and the elimination of bending are realized without forming a complicated structure dedicated to detour in the case body, the product can be downsized and the cost can be further reduced. .

[Brief description of the drawings]

FIG. 1 is an overall perspective view of an embodiment of the present invention.

FIG. 2 is a front view of the flexible wiring board according to the embodiment of the present invention.

FIG. 3 is an overall perspective view of another embodiment of the present invention.

FIG. 4 is a perspective view from the surface of a conventional case body.

FIG. 5 is a perspective view showing a state before a flexible wiring board is mounted on the back surface of a conventional case.

FIG. 6 is a perspective view showing a state after mounting in FIG. 5;

FIG. 7 is a perspective view showing a case where a conventional jumper wire is used.

FIG. 8 is a perspective view showing a case where a conventional second wiring board is used.

[Explanation of symbols]

 1, 30 case main body 11 meter surface 12 case back surface 12a, 32a first mounting surface 12b, 32b second mounting surface 12c, 32c third mounting surface 13 flexible wiring board 13a first circuit surface 13b second circuit surface 13c third circuit Surface 14 Mounting hole 15 Second bent portion 16 Branch wiring board 17 Third bent portion 18 Connected portion 19 First bent portion 19a Notched concave portion 20 Connection portion 33 Locking portion 34 Locking piece

Claims (3)

(57) [Claims] 1. A flexible wiring board having a plurality of circuit surfaces mounted on a case having a stepped concave portion or a convex portion in which wiring is difficult to pass because electronic components are concentrated, wherein the flexible wiring board is formed on the flexible wiring board. The first circuit surface,
A second circuit surface disposed on the concave portion or the convex portion where the electronic components are concentrated, a third circuit surface formed at a position facing the first circuit surface, and extending from the first circuit surface. A branch wiring board that is electrically connected to the third circuit surface while bypassing the concave or convex portion, and is in contact with the case at a free end of the branch wiring board.
Connected to a connection portion provided at a predetermined position on the third circuit surface.
A connected portion is provided to be connected to the third circuit surface so that the connected portion matches the connected portion on the third circuit surface.
The connected part is shifted by a predetermined length in the longitudinal direction.
A flexible wiring board characterized by being formed . 2. Since the electronic components are concentrated, the wiring
Attached to cases with difficult step-shaped recesses or protrusions
For manufacturing flexible wiring boards with multiple circuit surfaces
Here, the first circuit is formed by punching one flexible wiring board.
And a surface extending from the first circuit surface and having the concave portion or the convex portion.
A second circuit surface to be arranged, and further extending from the second circuit surface.
A third circuit surface extending from the first circuit surface;
Provided at a predetermined position on the third circuit surface, bypassing the second circuit surface
A branch wiring board having a connected part electrically connected to the connecting part
Formed and simultaneously with the flexing
A notch recess is formed in the sibble wiring board, and
The extended connected part is formed.
Manufacturing method of flexible wiring board . 3. The method according to claim 1, wherein the connected portion is connected to the third circuit surface.
The connected part is extended along the longitudinal direction so as to coincide with the continuation part.
Claims formed by shifting by a predetermined length
Item 4. The method for producing a flexible wiring board according to Item 3 .