JPH0590725A - Connecting structure of flexible board - Google Patents

Abstract

PURPOSE:To furnish a flexible board having a structure which ensures firm connection with a printed circuit board. CONSTITUTION:A reinforcing land 6 formed of a copper foil land is provided inside a contact pattern 3 in relation to the end of a flexible board 1 and, besides, a reinforcing land having the same shape substantially as the above is provided also on a printed circuit board 2 opposed to the board. This constitution enables attainment of the flexible board 1 which can make the firm connection with the printed circuit board 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible board, and more particularly to a flexible board connection structure for electrically connecting a flexible board and a printed board.

[0002]

2. Description of the Related Art Generally, a flexible board and a printed board are used by electrically connecting a contact portion such as a contact pattern on the flexible board and a corresponding contact portion on the printed board by soldering.

As a concrete structure for this electrical connection, conventionally, for example, at the substrate end of a flexible substrate, the coverlay film is removed to expose copper foil patterns arranged in parallel at a constant pitch. To form a contact pattern. A method is often used in which the contact patterns formed on the printed circuit board side are superposed on each other, and the solder previously attached to the surface of each contact pattern is melted to provide electrical connection.

The connection structure of this conventional example will be described with reference to FIG. In FIG. 2, reference numeral 1 denotes a flexible substrate, which is covered with a copper foil pattern by a coating layer 4. The covering layer 4 is generally called a cover lay film, and is formed of a material having high heat resistance and chemical resistance and resistant to bending, for example, a film of polyimide or the like. Then, by partially removing the coating layer 4 at the substrate end of the flexible substrate 1, the copper foil patterns arranged in parallel at a constant pitch are exposed to form the contact patterns 3. At this time, the surface of the contact pattern 3 is usually subjected to solder plating. Further, positioning holes 5 are provided on both sides of the contact pattern 3.

Reference numeral 2 denotes a printed board on which a contact pattern 3 and a positioning hole 5 of the same shape are formed at positions corresponding to the contact pattern 3 and the positioning hole 5 of the flexible board 1. In this case, the surface of the contact pattern 3 is usually subjected to a solder leveler process.

In the above structure, the flexible board 1 and the printed board 2 are aligned in the positioning holes 5, and the contact patterns 3 are in close contact with each other. Then, the contact patterns are heated by a soldering iron or a laser. Melt and fix the upper solder.

The flexible substrate 1 having such a structure
In the connection between the printed circuit board 2 and the printed circuit board 2, only the pattern width of the contact patterns at both ends is normally widened in the pattern row of the contact patterns to reinforce the peeling of the flexible board.

[0008]

However, in the connection structure between the flexible board 1 and the printed board 2 of the conventional example described above, when the number of electrical connections increases,
Alternatively, when the width of the flexible substrate 1 is narrowed and the width of the contact pattern is limited, it is necessary to narrow the pitch of the contact pattern, which easily causes a solder bridge between adjacent contact patterns. This has caused manufacturing difficulties. Further, when a force in the peeling direction is strongly applied to the flexible board 1, as shown in FIG. 3, the printed board 2 and the flexible board 1 are provided on the surface of the printed board 2 opposite to the surface to which the flexible board 1 is connected. There is a case where the adhesive tape 7 is attached and reinforced so that the adhesive tape 7 is straddled, but in this case, there is a problem in that it takes time and effort for manufacturing, the cost is increased, and the adhesive force of the adhesive tape 7 is weakened due to aging.

The present invention is intended to solve the above problems. That is, it is an object of the present invention to provide a flexible board having a structure for firmly connecting to a printed board.

[0010]

In order to achieve the above object, the present invention has a contact pattern having substantially the same shape as the contact pattern of a printed circuit board at the end of the opposing surface and soldered to the printed circuit board. In the flexible board electrically connected by means of the above, there is a reinforcing land with a copper foil land provided inside the contact pattern with respect to the end of the flexible board, and a reinforcing board having substantially the same shape on the opposing printed board. Land is assumed to be provided.

[0011]

According to the present invention, the reinforcing lands provided on the flexible board and the printed board are welded to each other by soldering to firmly connect the two boards.

[0012]

1 is a perspective view showing an embodiment of the present invention. In FIG. 1, 1 to 5 are the same as those in FIG. Further, 6 is a reinforcing land composed of a copper foil land provided inside the contact pattern 3 with respect to the substrate end of the flexible substrate 1, and is also provided at a position facing the printed circuit board 2.

Next, in the above structure, the surface of the contact pattern 3 and the reinforcing land 6 on the flexible substrate 1 is subjected to solder plating, and the surface of the contact pattern 3 and the reinforcing land 6 on the printed circuit board 2 is subjected to solder leveler treatment. Give each one. Then, positioning is performed using the positioning holes 5 provided on both sides of each contact pattern 3, and the solder on the contact pattern 3 is soldered by a heating means such as a soldering iron or a laser while the contact patterns 3 are in close contact with each other. Melting,
Fix it. At this time, the solder on the reinforcing land 6 is also melted and fixed at the same time.

In such a structure, the reinforcing land 6 is reinforced not only by the solder on the contact pattern 3 but also by the force for peeling the flexible substrate 1 from the printed circuit board 2.
Since the solder is also used, the connection is strong.

[0015]

As described above, according to the present invention,
In a flexible board that is connected to the contact pattern of the printed circuit board, a reinforcing land is provided inside the contact pattern with respect to the board edge, and the reinforcing land is welded at the same time as the soldering of the contact pattern enables a firm connection. Become. Further, it is not necessary to widen the pattern width of the contact patterns at both ends in the pattern row of the contact pattern, which is conventionally performed, and the width of the pattern row can be effectively utilized. Further, there is no need to attach an adhesive tape for reinforcement, which has the effect of cost reduction.

[Brief description of drawings]

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

FIG. 2 is a perspective view showing an example of a conventional technique.

FIG. 3 is a side view showing another example of the conventional technique.

[Explanation of symbols]

 1: Flexible substrate 2: Printed circuit board 3: Contact pattern 4: Covering layer 5: Positioning hole 6: Reinforcement land

Claims (1)

[Claims] 1. A flexible board having a contact pattern of substantially the same shape as a contact pattern of a printed board at an end portion of an opposing surface and electrically connected to the printed board by soldering, at the end of the flexible board. On the other hand, a connecting structure of a flexible board having reinforcing lands by copper foil lands provided inside the contact pattern, and reinforcing lands having substantially the same shape on the opposing printed circuit board. .