JPH05206603A - Flexible printed wiring board - Google Patents

Abstract

PURPOSE:To obtain a flexible printed wiring board which may be automatically mounted on a printed board by the same method as used for surface mounting type electronic parts and altogether soldered by a solder reflow furnace. CONSTITUTION:A flexible printed wiring board FPC1 is provided with a soldering terminal 5 and a reinforcing plate 2 bonded to the bonding part of a punchable position 3. The soldering terminal 5 of the flexible printed wiring board FPC1 and the soldering terminal 7 of a printed board 6 are soldered to each other and then the flexible printed wiring board and the bonding part of the punchable position 3 of the reinforcing plate 2 are cut off along a cutting line 15 by punching and removed to make a unitary construction including only the flexible printed wiring board FPC1 in which the reinforcing plate 2 is repeeled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible printed wiring board (hereinafter FPC) and a hard printed wiring board (hereinafter printed circuit board).
The present invention relates to an FPC capable of automatically mounting the FPC on a printed circuit board in the soldering step and having high soldering reliability in a solder reflow furnace.

[0002]

2. Description of the Related Art Conventionally, as a connection technique between an FPC and a printed circuit board, a method using a fitting type connector and an FP
Although there has been a method of directly soldering the C soldering terminal and the soldering land of the printed circuit board, etc., with the miniaturization of electronic devices, the method of higher density connection method is increasing.

[0003]

The direct soldering of the FPC and the printed circuit board is extremely difficult to automate because the FPC is film-shaped and highly flexible and easily bent or warped. The soldering work is often done by hand, and there are problems that soldering reliability is low and connection cost is high.

An object of the present invention is to solve the above-mentioned problems and to automatically mount an FPC on a printed circuit board by the same method as for surface mount type electronic parts (IC, chip parts, etc.) and solder them together by a solder reflow furnace. It is to provide an FPC having a structure capable of

[0005]

In order to achieve the above object, the present invention provides a flexible printed wiring board, wherein the flexible printed wiring board is partially bonded to a soldering terminal at a punchable position. It is provided with a backing reinforcing plate, and after connecting the soldering terminal of the flexible printed wiring board to the soldering terminal of the hard printed wiring board by soldering, the flexible printed wiring board and the backing reinforcing plate can be punched out. It is characterized in that it has a unitary structure of only the flexible printed wiring board in which the adhesive portion at various positions is removed by punching and the reinforcing plate is peeled off again.

Further, it is effective that the backing reinforcing plate is made of a metal and / or a heat-resistant resin that does not melt above the melting point of the solder.

[0007]

The present invention has a structure in which the FPC having the soldering terminals and the backing reinforcing plate are partially bonded at a punchable position, and the FPC is manufactured in the same manner as the surface mount type electronic component.
It enables automatic mounting of a PC on a printed circuit board and batch soldering connection in a solder reflow furnace.

Embodiments will be described below with reference to the drawings.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining a concrete structure of the present invention, in which an FPC 1 having a soldering terminal 5 is partially adhered to a backing reinforcing plate (hereinafter referred to as a reinforcing plate) 2 at a punchable position 3. It is adhered by the agent 4.

At this time, the FPC 1 may be either a single-sided wiring board or a double-sided wiring board, and the reinforcing plate 2 is made of a material having a melting point equal to or higher than the melting point of the solder and little deformation, such as metal or heat-resistant thermosetting resin.

The soldering terminal 5 is exposed, and after the soldering terminal 5 is aligned with the soldering terminal 7 of the printed circuit board 6, the soldering terminal 5 is mounted without bending in the vertical direction.
After connecting the soldering terminals 5 and 7 of each of the C1 and the printed circuit board 6 by soldering, the punchable position 3 of the bonded portion of the FPC 1 and the reinforcing plate 2 is cut and removed by the cutting line 15 by punching, and the reinforcing plate 2 is removed. It is peeled again, and the FPC 1 is used in a single structure.

In the FPC 1 having the above-mentioned structure, since the reinforcing plate 2 is partially strongly adhered, the FPC 1 does not bend or warp, and the suction and transfer by the automatic mounting machine is easy.
The positioning with respect to the printed circuit board 6 can maintain the same accuracy as that of a normal electronic component.

After mounting on the printed circuit board 6, the FPC 1 is mounted on the printed circuit board 6 due to an appropriate load of the reinforcing plate 2 itself.
To prevent the soldering terminal 5 of the FPC 1 from being bent or lifted, and no misalignment occurs during transportation.

Further, since the adhesion between the FPC 1 and the reinforcing plate 2 is strong even in the solder reflow furnace, it is possible to prevent the displacement of the soldering terminal 5 or the terminal floating due to the dimensional shrinkage of the FPC 1.

After the solder reflow, the reinforcing plate 2 can be surely removed by cutting the punchable position 3 of the bonded portion of the FPC 1 and the reinforcing plate 2 by punching.
The unnecessary reinforcing plate 2 or the adhesive 4 does not adhere to the PC 1 at all, and the flexibility, high flexibility, and folding resistance of the FPC 1 are secured in the actual use state.

The punching at the punchable position 3 of the adhesive portion can be performed at the same time as the punching of the printed circuit board 6, so that no extra work is added.

Comparative examples will be shown below in comparison with the examples based on the specific constitution of the present invention.

Example:

FIG. 2 shows the structure of the essential part of the embodiment.

The FPC 9 on which the soldering terminals 8 are formed is preliminarily soldered to the printed circuit board 14 in which the reinforcing plate 10 made of aluminum T1.0 is partially firmly bonded through the adhesive 11 at the punchable position 16. The solder paste 13 was printed on the attachment terminals 12 automatically on the printed circuit board 14, and the suction-conveyability of the automatic mounting machine was examined.

Subsequently, the solder paste 13 is melted through a solder reflow furnace, and then the solder paste 13 is punched by a die process to obtain F.
For the PC 9, the adhesive portion of the reinforcing plate 10 at the punchable position 16 was cut along the cutting line 15, and the soldering state, floating, and displacement of the soldering terminal 8 of the FPC 1 were examined.

The evaluation results are shown in Table 1.

In the display of Table 1, ◯ is good, ◎ is extremely good,
× means no.

Comparative Example:

FIG. 3 shows the structure of the main part of the comparative example.

The FPC 9 similar to that of the embodiment is automatically attached to the printed circuit board 14 on which the solder paste 13 is printed on the soldering terminals 12 in advance in the state where the reinforcing plate is not adhered, so that the suction conveyance property of the automatic attaching machine can be improved. Examined.

Subsequently, after the solder paste 13 was melted through a solder reflow furnace, the soldering state, floating and displacement of the soldering terminals 8 of the FPC 9 were examined.

The evaluation results are shown in Table 1.

[0029]

[Table 1]

As is clear from the above evaluation results, it has been found that the FPC of the present invention can easily and reliably perform soldering connection with a printed circuit board by automatic mounting.

[0031]

As described above, the FPC of the present invention is
With the structure in which the FPC with the soldering terminals and the reinforcing plate are partially bonded at the punchable position, the FPC can be automatically mounted on the printed circuit board and solder reflow furnace in the same manner as surface mount electronic components. FPC between printed circuit boards for electronic devices because it is possible to solder together
The high-density connection can be performed in the same process as other electronic components without manual work, which greatly contributes to the reliability and cost reduction of electronic devices.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a specific configuration example of the present invention.

FIG. 2 is a configuration diagram of a main part of an embodiment of the present invention.

FIG. 3 is a configuration diagram of a main part of a comparative example.

[Explanation of symbols]

 1 FPC 2 Reinforcing Plate 3 Punchable Position (Adhesive Part) 4 Adhesive 5 Soldering Terminal 6 Printed Circuit Board 7 Soldering Terminal 8 Soldering Terminal 9 FPC 10 Reinforcing Plate (Aluminum T1.0) 11 Adhesive 12 Soldering Terminal 13 Solder paste 14 Printed circuit board 15 Cutting line 16 Punchable position (adhesive part)

Claims (2)

[Claims] 1. A flexible printed wiring board comprising a soldering terminal and a backing reinforcing plate partially adhered at a punchable position, the flexible printed wiring board comprising: After the soldering terminals of the board are connected to the soldering terminals of the hard printed wiring board by soldering, the reinforcing portion is removed by punching away the adhesive portions of the flexible printed wiring board and the backing reinforcing plate at the punchable positions. A flexible printed wiring board having a unitary structure of only the flexible printed wiring board that has been peeled off again. 2. The flexible printed wiring board according to claim 1, wherein the backing reinforcing plate is made of a metal and / or a heat-resistant resin that does not melt above the melting point of the solder.