JPH0537493Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a connector connection structure for a flexible printed circuit board.

[Conventional technology]

In recent years, due to demands for thinness, weight reduction, ease of assembly, etc., instead of the conventional rigid printed circuit board made of epoxy resin, flexible thin film circuit boards, that is, formed on a base frame, have been developed. 2. Description of the Related Art So-called flexible printed circuit boards, in which conductive foil forming an electric circuit is covered and protected with an overlay film, have come to be used in various electronic devices, vehicle lights, and the like. Figures 3 to 5 show a conventional connector mounting structure in which a connector is directly soldered to such a flexible printed circuit board, and 1 shows a flexible printed circuit bent into a substantially U-shape formed in a band shape. A board 2 is a connector mounted on a connector connecting portion 3 of the flexible printed circuit board 1. The flexible printed circuit board 1 is composed of a base film 4 and an overlay film 5 made of polyester, polyimide, etc., and a plurality of conductive foils 6 formed between these films 4 and 5. One end of the connector 6 is arranged in a concentrated manner on the connector connecting portion 3 to form a land portion 6a. Each land portion 6a has a pin insertion hole 7 with one end opening on the back surface of the base film 4 and the other end opening on the surface of the overlay film 5. A ring-shaped gold foil 8 is provided on the surface of the overlay film 5 so as to correspond to the pin insertion hole 7. Connector 2 mounted on the connector connection part 3
A plurality of pins 9 vertically provided on the lower surface are inserted into pin insertion holes 7 of each land portion 6a, and are connected and fixed to the land portion 6a with solder 10, and are connected to, for example, a printing head of a printer. be done.

Note that a reinforcing plate 12 is attached to the lower surface of the connector connecting portion 3 as necessary.

[Problems to be solved by the invention] By the way, as the name suggests, the flexible printed circuit board 1 is flexible and is therefore suitable for use in wiring locations that are susceptible to bending stress. Each time the connector is bent, stress is concentrated on the connector connecting portion 3. In this case, the land portion 6b of the common electrode conductive foil 6A, which has a larger width than the other land portions 6a, is particularly rigid and difficult to bend, and if it is forcibly bent, this portion will eventually break. There was a drawback.

Further, if the widths of the land portions 6a and 6b are different, there will be a difference in soldering time, and it is necessary to set the time to match the width of the land portion 6b when dipping.

Therefore, the present invention was made to solve the above-mentioned drawbacks, and by reducing the rigidity and increasing the flexibility of the conductive foil land portion for the common electrode, stress concentration and wire breakage can be prevented. It is an object of the present invention to provide a connector connection structure for a flexible printed circuit board that can provide a flexible printed circuit board with a uniform soldering time.

[Means for solving problems]

In order to achieve the above object, the present invention is such that the land portion of the conductive foil for the common electrode is branched into finger shapes by a plurality of slits formed in parallel.

[Effect]

In the present invention, the land portion of the conductive foil for the common electrode is branched into finger shapes by the slit to reduce its rigidity. Further, each finger portion can be set to have substantially the same width as other narrow land portions.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a sectional view showing an embodiment of a connector connection structure according to the present invention, and FIG. 2 is a plan view of a connector connection portion of a flexible printed circuit board. Components and parts that are the same as those in FIGS. 3 to 5 are designated by the same reference numerals, and their explanations will be omitted. In these figures, in this embodiment, the land portion 6b of the common electrode conductive foil 6A is branched into a finger shape by a plurality of slits 20, for example, two slits 20 extending in the longitudinal direction of the land portion 6b. is different from the conventional structure described above, but the other structures are the same. Each of the finger portions 21a to 21c branched by the slit 20 has approximately the same width as the land portion 6a of the other conductive foil 6, and a pin insertion hole 7 is formed at the tip thereof.

In the connector connection structure of the flexible printed circuit board 1 having such a configuration, a slit 20 is formed in the land portion 6b of the common electrode conductive foil 6A.
, and its rigidity is kept low, so that the flexibility of the connector connecting portion 3 is increased and bending is facilitated. Therefore, the bending stress at the time of bending can be divided, stress is not concentrated on the land 6b, and disconnection of the connector connecting portion 3 is prevented. Further, each finger portion 21a to 21c is separated by a slit 20 and constitutes an independent land portion like the other land portions 6a, so that the pin insertion hole 7 of these finger portions 21a to 21c is The solder 10 of the inserted pin 9 does not form a bridge, and the soldering time can be made to match the soldering time at the land portion 6a, improving the reliability of the dip soldering work.

[Effect of idea]

As explained above, in the flexible printed circuit board connector connection structure according to the present invention, the land portion of the common electrode conductive foil at the connector connection portion of the printed circuit board is branched by the slit, so that the rigidity of the land portion is reduced. , increasing the flexibility of the connector connection. Therefore, even if the printed circuit board is bent, stress is not concentrated, it is possible to prevent disconnection of the connector connection part, and it is possible to improve durability. Furthermore, since the width of the land portion can be made uniform, there is no variation in soldering time, which is effective and highly effective for soldering by the dip method.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a plan view of main parts of a flexible printed circuit board, Fig. 3 is a perspective view showing a conventional example of a connector connection structure, Fig. 4 is a sectional view of the same structure, and Fig. 5 is a plan view of main parts of a flexible printed circuit board. It is. 1...Flexible printed circuit board, 2...
Connector, 3... Connector connection portion, 4... Base film, 5... Overlay film, 6...
Conductive foil, 6A...Conductive foil for common electrode, 6a, 6b
... Land part, 7 ... Pin insertion hole, 9 ... Pin,
10...Solder, 20...Slit, 21a-21
c...Finger section.

Claims (1)

[Scope of utility model registration request] In the flexible printed circuit board, the pins of the connector are inserted into pin insertion holes formed through the land portions of each conductive foil in the connector connection portion of the flexible printed circuit board, and are connected and fixed to the land portions with solder. A connector connection structure for a flexible printed circuit board, characterized in that a land portion of a conductive foil for a common electrode is branched into finger shapes by a plurality of slits formed in parallel.