JPH02216888A - Double-sided printed circuit board connection device - 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] Industrial Application Fields The present invention relates to one side and the other side (hereinafter, one side is referred to as the front side and the other side is referred to as the back side) of a double-sided printed circuit board used in various electronic devices. This invention relates to a conductive pattern connection device.

<Summary of the Invention> The present invention is a double-sided printed circuit board connection device that forms an electrically conductive part between front and back conductive patterns on a double-sided printed circuit board using a connecting tool in which a conductive soft core wire is coated with solder. Insert both ends of the U-shaped connector into a pair of through holes drilled corresponding to the parts where the front and back conductive patterns to be connected face each other, and the parts protruding from the through holes. The connectors are temporarily fixed to the board by bending the connectors, the solder covering is melted, and the core wires are soldered to the conductive patterns on the front and back sides to be connected.

<Prior Art> Conventionally, as a method of forming electrically conductive portions on the front and back sides of a double-sided printed circuit board, there is a method of using eyelets. As shown in FIG. 5, a through hole 1a is bored in the conductive pattern 2.3 provided on both sides of the substrate l, and an eyelet 4 made of copper or the like is inserted into the through hole 1a. , one end of the eyelet 4 is caulked to press both ends 4a and 4b to the conductive pattern 2.3, thereby connecting the conductive patterns 2.3 on both sides of the substrate.

Furthermore, in recent years, a method of forming electrically conductive parts on the front and back surfaces of a substrate by through-hole plating as shown in FIG. 6 has been widely adopted. This is the conductive pattern 2 on both sides of the board 1.
．． A through hole tb is bored in the through hole 1b, and a cylindrical copper plating layer 5 is formed on the inner wall surface of the through hole 1b by chemical plating or electroplating.
It connects.

<Problems to be Solved by the Invention> However, in the method using eyelets shown in FIG. A crack will appear in the board I at the point of contact with the board, causing damage to the board.

Also, if the crimping force is weak, the eyelet 4 will have a poor connection.
This resulted in poor work efficiency and high costs.

On the other hand, in the method of through-hole plating shown in Fig. 6, there are many plating steps, and due to heat stress etc.
Cracks occur in the copper plating layer 5 at the corner portions 1c and lc of b, and poor connections are likely to occur, resulting in disadvantages such as poor work efficiency and difficulty in process control. Further pre-processing (through hole tb
Even in the hole drilling process, a uniform machined surface is required to maintain the accuracy of the taimetsuki layer 5, so punching that can be used for high-speed mass production is not possible, so drilling is used.
Here too, work efficiency was poor, leading to high costs.

<Means for Solving the Problems> The present invention aims to solve the above-mentioned conventional problems, and particularly improves the reliability of soldering when connecting the conductive patterns on the front and back sides of a double-sided printed circuit board with a cutting tool. Highly sexual,
The present invention aims to provide a connecting device for double-sided printed circuit boards that is easy to manage and manage, and is easy to automate.

For this reason, in the present invention, a conductive soft core wire is covered with solder and then bent to form a mouth-shaped connector. On the other hand, a pair of through holes are formed in the double-sided printed circuit board corresponding to the portions where the front and back conductive patterns to be connected face each other.

Then, both ends of the connecting tool are inserted into a pair of through holes of a double-sided printed circuit board, and the parts protruding from the through holes are bent in a direction approaching the conductive pattern to be connected, and the connecting tool is temporarily fixed to the board. Then, the solder coated on the connector is melted, and the core wire is soldered to the conductive patterns on the front and back sides.

Function> Since the connecting tool according to the present invention is formed in the shape of an opening, it can be mounted on a board in the same way as a general axial component. In addition, a part of the attached connector is located on the front and back conductive patterns to be connected, so if the connector is heated in this state, the solder covering will melt and the core wire will be on the front and back conductive patterns to be connected. It is reliably soldered to the conductive pattern.

<Example> Embodiments of the present invention will be described below with reference to the drawings.

In Figures 1 to 4, reference numeral 6 denotes a connector, which is formed by coating the outer periphery of a core wire 6a made of a single wire such as annealed copper wire, which is soft and has good solder adhesion and thermal conductivity, with solder 6b.

Reference numeral 7 denotes a double-sided printed circuit board with conductive patterns arranged on both the front and back sides, and a pair of through holes 7a and 7b are formed by punching or the like in the portion where the front and back conductive patterns 8.9 to be connected face each other; The through hole 7a.

The conductive pattern 8.9 is arranged between the conductive patterns 7b.

When electrically connecting the front and back conductive patterns 8.9 using the connecting tool 6, the connecting tool 6 is first bent into an opening shape and both ends thereof are inserted into the through holes 7a and 7b. Next, the ends of the connector 6 protruding from the through holes 7a and 7b are bent inward and temporarily fixed to the board. In this way, a part of the connecting tool 6 is always located on the conductive pattern 8.9, so that
For example, when reflow soldering other mounted components, the connector 6 is heated and when the temperature reaches the melting point of the solder or higher, the solder 6b coated on the core wire 6a becomes fluidized, and with the help of flux etc., capillary phenomenon occurs. The core wire 6a is fused to the front and back conductive patterns 8.9. Therefore, the core wire 6a of the connector 6 is soldered to the conductive patterns 8.9 on the front and back sides using its own solder 6b, thereby forming an electrically conductive portion on the front and back sides of the board.

Also, when dip-soldering other mounted components, since the solder 6b melts due to conduction heat while the dip surface is immersed in the dip bath, the core wire 6a is connected to the front and back conductive patterns 8. 9 can be soldered.

Since the connecting tool 6 has a variable configuration in its length direction, if a connecting tool of sufficient length is prepared, it can be automatically attached to the board by a well-known automatic attaching method.

That is, the connector can be appropriately cut using an insert machine, bent into an opening shape, and attached to the board. This automatic attachment method is used when attaching jumper wires to a board. Furthermore, if the connecting tool 6 is bent in advance into an opening shape, it is possible to automatically attach it using an insert machine for axial parts.

The material and diameter of the core wire used for the connector 6 and the amount of solder to be coated are determined according to the design conditions of the double-sided printed circuit board 7.
It may be selected and processed as appropriate.

<Effects of the Invention> As described above, according to the double-sided printed circuit board connection device of the present invention, since the connecting tool is formed in the shape of an opening, the connecting tool can be attached to the board using the same mounting method as general axial components. It can be temporarily fixed. A part of the attached connector is located on the front and back conductive patterns that must be connected, so by melting the solder coating in this state, the core wire can be reliably soldered to the front and back conductive patterns that should be connected. It is possible to easily form electrically conductive parts on the front and back surfaces of the substrate. Further, since the solder of the connector can be melted at the same time as the soldering of other parts, there are fewer work steps and the work efficiency is high.

In addition, compared to the conventional example, I) there is no need for work such as caulking, so there is no risk of damaging the board.

2) Since the length, material, etc. of the connector can be appropriately selected and processed according to the design conditions of the double-sided printed circuit board, extremely high reliability can be obtained in connection between the front and back conductive patterns.

3) A high degree of processing precision is not required to drill through holes;
It is possible to employ punching processing, which is simple, can be processed at high speed, and is advantageous in terms of cost.

There are other effects.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the connecting device before solder melting, showing the connecting device for a double-sided printed circuit board according to the present invention, Fig. 2 is a cross-sectional view of the connecting device after the solder is melted, showing the connecting device for a double-sided printed circuit board of the present invention, FIG. 4 is a cross-sectional view of a double-sided printed circuit board according to the present invention, FIG. 4 is a perspective view of a connecting tool according to the present invention, and FIGS. 5 and 6 are cross-sectional views showing conventional connecting devices for double-sided printed circuit boards. 6... Connector, 6a... Core wire, 6b... Solder, 7
...Double-sided printed circuit board, 7a, 7b...Through hole, 8,
9... Conductive pattern. Agent Patent Attorney Takeshi Sugiyama (and 1 other person) Foil 1 Figure fsJ Figure 5 Figure 2 a Figure 4 txB Figure

Claims (2)

[Claims] 1. A conductive pattern is provided on one side and the other side, and a pair of through holes are bored in the conductive pattern corresponding to the portions of the conductive pattern where the conductive patterns on one side and the other side face each other to be connected. A double-sided printed circuit board and a soft conductive core wire are coated with solder, the coated solder is melted, and the core wires are soldered to the conductive patterns on one side to be connected and the other side of the double-sided printed circuit board. a connecting tool, the connecting tool is formed in a U-shape,
A double-sided printed circuit board characterized in that both ends of the double-sided printed circuit board are inserted through a pair of through holes, and the portions protruding from the through holes are respectively bent in a direction approaching a conductive pattern to be connected and temporarily fixed. connection device. 2. The conductive patterns on one side and the other side to be connected are arranged between the pair of through holes of the double-sided printed circuit board, and the parts of the connector at both ends protruding from the pair of through holes are respectively bent inward. A connecting device for double-sided printed circuit boards according to claim 1, characterized in that: