JPH08335752A - Flexible wiring board and its manufacture - Google Patents

Abstract

PURPOSE: To prevent the fracture of film base and breakage of conductor pattern by the accompanied winding of the film base when a screw is tightened at the fixing part of a flexible wiring board. CONSTITUTION: The flexible wiring board comprises a film base 1, a conductor pattern 2 formed on it, a reinforcing board 4 bonded to any one side of the film base 1, a screw fixing hole 5 made at same position in the film base 1 and the reinforcing board 4, and a slit 7 having diameter larger than that of screw head part 6 made concentrically to the screw fixing hole 5 in the film base 1. The slit 7 is provided, at one or more point, with a part 10 for coupling the film base 1 on the outside of slit 7 with a film base 1a on the inside of slit 7.

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 used for wiring connections of various circuits inside various electronic devices and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, flexible wiring boards have come to be used more and more in order to reduce the size and weight of equipment and increase the density thereof. In such a situation, as shown in FIG. 3, when the film base 31 of the flexible wiring board is attached to the chassis 32 or the like with screws (screws) 33 or the like, the film base 31 alone is thin and difficult to attach. . Therefore, the reinforcing plate 34 for mounting
Is attached to the film base 31 with a double-sided tape (adhesive) 38 and attached to the chassis 32 or the like. At this time, if the screw mounting holes 35 are formed at the same time, the screw head 33a wraps around the film base 31 to generate wrinkles 36 when the screw 33 is tightened, and further the film base 31 is damaged and the conductor pattern 37 is cut. Many occur.

As a countermeasure, a double-sided tape (adhesive) 38 or the like is attached to the film base 31 of the flexible wiring board, and as shown in FIG. The release paper of (adhesive) 38 is peeled off, and the reinforcing plate 3 having the screw mounting holes 35 is processed.
4 is a film base 31 and a screw head relief hole 3
9 is positioned and adhered so as to be concentric with each other, so that the screw head 33a is not affected by the screw head 33a on the film base 31.
It is configured such that a directly presses the reinforcing plate 34.

FIG. 5 shows a process of assembling the mounting portion of the conventional flexible wiring board thus constructed.

[0005]

However, even in the flexible wiring board on which the above-mentioned conventional measures are taken, as shown in FIG. 5, in order to form a screw attachment portion, a double-sided tape is attached to the film base 31, and a film is attached. A lot of man-hours are required, such as screw head relief hole processing on the base 31, reinforcing plate outer shape and mounting hole processing, reinforcing plate positioning (positioning on the bonding jig to be concentric), double-sided tape release paper peeling / pasting The processing mold is a screw head relief hole processing of the film base 31, a reinforcing plate outer shape processing, a screw mounting hole processing, and 2-3.
However, there is a problem that the screw head escape hole 39 and the screw mounting hole 35 are concentric with each other, and a positioning jig is used for assembly to increase costs and man-hours.

The present invention is intended to solve such conventional problems, and an object of the present invention is to provide an inexpensive and high-performance flexible wiring board with reduced man-hours and a method for manufacturing the same.

[0007]

A flexible wiring board of the present invention which solves the above-mentioned problems is adhered to either one surface of a film base, a conductor pattern formed on the film base, and the film base. Reinforcing plate,
A screw mounting hole provided at the same position of the film base and the reinforcing plate, and a slit concentric with the screw mounting hole provided on the film base and having a diameter larger than the diameter of the screw head are provided on the film base side. The structure further includes an adhesive layer.

[0008]

In the flexible wiring board having the above-mentioned structure, when the screw is tightened, the portion tightened by the screw head is
Since it is separated from the conductor pattern of the film base by the slit, breakage of the film base and cutting of the conductor pattern are eliminated.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A flexible wiring board according to an embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the flexible wiring board of this embodiment has a film base 1, a conductor pattern 2 formed on the film base 1, and a double-sided tape ( Reinforcement plate 4 adhered with adhesive 3, screw attachment hole 5 provided at the same position of film base 1 and reinforcement plate 4, and screw attachment hole 5 provided on film base 1 with the same screw A slit 7 having a diameter larger than that of the head 6 is provided. At this time, the slit 7 is provided from the film base 1 side to the double-sided tape (adhesive) 3, and the joint portion 10 is the inner film base 1a.
Are connected by a width that is barely held.

When the film base 1 of the flexible wiring board constructed as described above is attached to the chassis 8, it is tightened by screws (screws) 9. On this occasion,
Since the head 6 of the screw (screw) 9 presses the reinforcing plate 4 via the slit 7 provided in the film base 1, the tightening force of the screw (screw) 9 causes the film base 1 on the outside and inside of the slit 7. The joint portion 10 connecting the 1a is broken, and the film base 1a inside the slit 7 is separated from the film base 1 outside thereof. As a result, no force is applied to the conductor pattern 2 provided on the film base 1, and damage or cutting of the conductor pattern 2 can be prevented.

At the same time, in terms of the processed surface, as shown in FIG.
Screw (screw) head relief slit processing, double-sided tape release paper peeling, reinforcing plate attachment, flexible wiring board outline /
It can be manufactured in 5 steps: screw (screw) mounting hole processing.

Alternatively, the screw (screw) head relief slit processing is performed, and the flexible wiring board outer shape and screw (screw) mounting hole processing is performed by using a Thomson die to process the slit 7 and the screw mounting hole 5 to the height of the cutting tool. If the simultaneous processing is performed by giving a difference, it becomes four steps, which reduces the number of mold surfaces and the number of work steps.

Further, when assembling in the above process, since the slit 7 and the screw mounting hole 5 can be simultaneously processed, the accuracy of sticking the reinforcing plate 4 to the film base 1 is not so required, so that no sticking jig is required. Becomes

In the above embodiment, the slit 7 is processed on both the film base 1 and the double-sided tape 3, but when the strength of the double-sided tape (adhesive) 3 is weak,
It should be added that even if the double-sided tape (adhesive) 3 does not have the slit 7, the same effect can be obtained.

[0016]

As is apparent from the above description, according to the flexible wiring board and the manufacturing method thereof of the present invention, the flexible wiring board used for wiring connection of each circuit inside the electronic device is reinforced by the base film. The screw (screw) head relief slit processing can be performed simultaneously with the flexible wiring board outer shape processing after the boards are attached, and it is possible to provide an inexpensive and high-performance flexible wiring board with a reduced number of work steps.

[Brief description of drawings]

FIG. 1A is a plan view of a flexible wiring board according to an embodiment of the present invention. FIG. 1B is a sectional view taken along line AA ′ of FIG.

[Fig. 2] Assembly process drawing of the flexible wiring board

FIG. 3A is a plan view of a conventional flexible wiring board, and FIG. 3B is a sectional view taken along line B-B ′ of FIG.

FIG. 4A is a plan view of a conventional flexible wiring board in which measures against screw entrainment have been implemented, and FIG. 4B is a sectional view taken along line CC ′ of FIG. 4A.

FIG. 5: Assembly process diagram of the flexible wiring board

[Explanation of symbols]

 1 Film base 2 Conductor pattern 3 Double-sided tape 4 Reinforcing plate 5 Screw mounting hole 6 Screw head 7 Slit 9 Screw 10 Connecting part

Claims (4)

[Claims] 1. A film base, a conductor pattern formed on the film base, a reinforcing plate adhered to either surface of the film base via an adhesive layer, the film base and the reinforcing plate. A flexible wiring board having a screw mounting hole provided at the same position and a slit concentric with the screw mounting hole provided on the film base and having a diameter larger than the screw head diameter. 2. The flexible wiring board according to claim 1, wherein the slit is provided with at least one connecting portion for connecting the film bases inside and outside the slit. 3. The flexible wiring board according to claim 1, wherein the film base has slits provided up to the adhesive layer. 4. A conductor pattern is formed on a film base, and a reinforcing plate is attached to either surface of the film base via an adhesive layer, and then a through hole for screw attachment and the screw attachment hole are formed. 4. The method for manufacturing a flexible wiring board according to claim 1, wherein a slit having a diameter larger than the diameter of the screw head is concentrically provided from the film base side to the adhesive layer.