JPS58125898A - Connecting system for printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a flexible printed wiring board and a rigid printed wiring board (
This relates to a connection method for electrically connecting a substrate (substrate).

Conventionally, insulated cord lead wires have been mainly used when electrically connecting other board terminals or electrical components to wiring portions of rigid printed wiring boards. That is, as shown in FIG. 1, connectors 2, 2 are provided at both ends of an insulated cord lead wire 1, one of these connectors is connected to a connector provided on a hard printed wiring board, and the other is connected to another board terminal or terminal to be connected. ′
The two are electrically connected by connecting to connectors provided on the electrical components.

However, in the conventional connection method described above, the number of insulated cord lead wires increases, and as the number of locations to be connected increases, wiring costs and work costs tend to increase.

Therefore, a method to solve this problem is to print a connection pattern on a flexible plastic film base material such as polyester in advance and use it for electrical connection between the rigid wiring board and other electrical components. 1. This connection method has many advantages such as simplification of wiring, improvement of workability, reduction of wiring and work costs, etc., and is a very effective connection method. The problem is that electrical connections are extremely difficult. For example, when using conductive adhesives, there are concerns about mechanical strength.
If solder is used, there is a risk that the flexible plastic film wiring board may be deformed by heat, and if the connection is made by crimp using anisotropic conductive rubber, the contact resistance may not be sufficiently reduced, and it may be difficult to use as a lead connector. Unstable for use. In addition, the method of providing commercially available connectors on both wiring boards for connection has the disadvantage that the volume of the wiring boards increases, leading to an increase in the size of the equipment and further increasing costs.

The present invention has been made in view of these points, and provides a connection method that electrically and firmly connects a flexible printed wiring board and a rigid printed wiring board using a very simple and inexpensive method. It is.

The system of the present invention will be explained below based on the figures.

FIG. 2 is a plan view of a flexible printed wiring board used in the method of the present invention, and FIG. 3 is a longitudinal cross-sectional view of a connecting portion between a rigid printed wiring board and a flexible printed wiring board according to the method of the present invention.

The flexible printed wiring board is made of an insulating and flexible plastic film such as a polyester film 4 as a base material.
A carbon-coated wiring 5 consisting of an AL layer 6 and a carbon layer 7 is provided thereon, and a through hole 9 for a pin, which will be described later, is formed in a terminal portion 8 of the wiring.

The flexible printed wiring board 4 configured in this manner is placed on a hard printed wiring board 10 as shown in FIG.
The through holes 9 drilled in the terminal portions 8 of the wiring boards 4 and 10 are aligned, and both wiring boards 4 and 10 are temporarily fixed with an adhesive 12.

After that, conductive pins 13 with enlarged tops are inserted into the through holes 9 and through holes 11 of both wiring boards as shown in the figure, and solder 14 is poured through the through holes 11 on the back side of the hard printed wiring board 10. , the flexible printed wiring board 4, the rigid printed wiring board 10, and the conductive pins 13 are fixed by soldering.

According to this connection method, the through holes 11 provided in the terminal portion 8 of the flexible printed wiring board 4 and the wiring portion of the rigid printed wiring 10 are connected to very small conductive pins 13 and solder 1.
4 ensures mechanical and electrical connection. especially,
Since soldering is performed from the back side of the rigid printed wiring board 10, the influence of heat on the flexible printed wiring board 4 is reduced, and thermal deformation can be prevented.

In the above embodiment, a through hole 9 for pin insertion is pre-drilled in the terminal portion of the flexible printed wiring board 4, but the pin 13 is inserted through the hole without specifically drilling it. You can do it like this. However, providing the through hole 9 has the advantage of making positioning easier.

As described above, according to the connection method according to the present invention, a flexible printed wiring board and a rigid printed wiring board can be electrically and firmly connected by a very simple and inexpensive method.

Therefore, it is possible to conduct wiring with a degree of freedom using the flexible printed wiring board, and the wiring is extremely simplified, so that wiring costs and work costs can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the conventional connection method, and FIG. 2 is a plan view of a flexible printed wiring board used in the method of the present invention.
FIG. 3 is a longitudinal sectional view of a connecting portion between a rigid printed wiring board and a flexible printed wiring board according to the method of the present invention. 4 is a flexible printed wiring board, 5 is carbon-covered wiring, 8
1 is a terminal portion, 9 is a through hole, 10 is a hard film wiring board, 11
is a through hole, and 14 is a solder.

Claims (1)

[Claims] 1. Laminate the through-hole portion of the rigid printed wiring board and the wiring pattern/portion of the flexible printed wiring board to be connected, and conduct electricity from the flexible printed wiring board side to the combined portion. 1. A method for connecting printed wiring boards, characterized in that after a plastic bottle is inserted, solder is poured into a through-hole on the back side of the hard printed wiring board to electrically connect the two wiring boards.