JPH11145608A - Printed board and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to connect reliably the first and second lands on both surfaces of a board with each other via a conductor wire, by a method wherein a conductor wire with the end parts inserted in holes formed on the board and the first land are connected with each other with reflow soldering, and at the same time the conductor wire and the second land are connected with each other by dip soldering. SOLUTION: A cream solder is printed on a printed board 1 and thereafter, the solder is fused by exposing hot air to the side of the upper surface of the printed board 1 and a land 7 is soldered to a jumper wire 5. Then, by passing the board 1 through a dip soldering vat, a land 4 under the lower surface of the board 1 and one end of the wire 5 are soldered to each other. In such a way, the land 7 on the upper surface of the board 1 and the land 4 under the lower surface of the board 1 are electrically connected with each other via the wire 5. As a result, at the time of dip soldering, it is eliminated that the solder of a part soldered by reflow comes off completely from the part and the connection between both lands can be reliably made.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board used for various electronic devices and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 7 shows a cross section of a part of a conventional printed circuit board in which lands on both sides of the printed circuit board are connected by conductive wires (jumper wires). 7, reference numeral 1 denotes a printed circuit board, 2A and 2B denote holes formed in the printed circuit board 1, 3 denotes a land formed at the edge of the hole 2B on the upper surface of the printed circuit board 1, and 4 denotes a lower surface of the printed circuit board 1. This is a land formed on the edge of the hole 2A. Reference numeral 5 denotes a jumper wire. Both ends of the jumper wire 5 are bent by approximately 90 degrees, and the bent portions at both ends are inserted into the holes 3 and 4, respectively. Be stopped.

In the conventional example shown in FIG. 7, first, the land 3 and the jumper wire 5 are soldered on the upper surface side by solder dip first, and then the land 4 and the jumper wire 5 are soldered on the lower surface side second time. The wire 5 was soldered.

[0004]

However, when the solder dip is performed twice as in the above-described conventional example, the solder 6A adhered in the first solder dip at the time of the second solder dipping is used at the time of the second solder dipping. The first soldering portion was insufficiently connected, cracks and the like occurred, and the soldering portion between one side of the land and the jumper wire was insufficiently connected.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a printed circuit board capable of reliably soldering a jumper wire to a land on the upper surface and a land on the lower surface of the printed circuit board, and a method of manufacturing the same. It is assumed that.

[0006]

According to the present invention, a first land is formed between holes on one surface of a substrate and a hole is formed on one surface of the other surface of the substrate. A second land is formed on the edge, and the end is connected to the first land with the conductive wire inserted into the hole by reflow soldering, and the conductive line and the second land are connected with a solder dip. According to the present invention, the first and second lands formed on both sides of the substrate can be reliably connected by the conductive wire.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to a first aspect of the present invention is directed to a substrate having at least a pair of holes formed therein and a first substrate formed between the pair of holes formed on one surface of the substrate. A land, a second land formed at an edge of one hole on the other surface of the substrate, and conductive wires having both ends inserted into the holes, respectively, wherein the first land and the conductive wire are provided. Are connected by reflow soldering, and the second land and the end of the conductive wire are connected by a solder dip. According to the present invention, the first land and the second land are connected to each other. And the land can be reliably connected.

According to a second aspect of the present invention, the position of the first land formed between the holes on one surface of the substrate is formed near another hole different from the hole connected by the solder dip. Since the distance between the soldered portion of the first land and the soldered portion of the second land is large, cracks in the soldered portion due to expansion and contraction of the substrate due to a change in temperature are reduced. It can be prevented.

According to a third aspect of the present invention, there is provided a step of inserting an end of a conductive wire into each of the holes of the substrate having at least a pair of holes, and the step of inserting the ends of the pair of holes on one surface of the substrate. A step of printing cream solder in a range including the first land formed between the holes; a step of applying hot air to reflow solder the conductive wire and the first land; Connecting the second land formed on the edge of one of the holes of the surface and the end of the conductive wire through a solder dip tank. According to the present invention, The first land and the second land can be reliably connected by a conductive wire.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIGS. 1 to 6 are views showing a process of soldering a printed circuit board according to this embodiment.

In FIG. 1, 1 is a printed circuit board, 2
A and 2B are holes formed in the printed circuit board 1, 7 is a land formed between the holes 2A and 2B on the upper surface of the printed circuit board 1,
Reference numeral 4 denotes a land formed at the edge of the hole 2A on the lower surface of the printed circuit board 1. Reference numeral 5 denotes a jumper wire, and both ends of the jumper wire 5 are bent substantially 90 degrees.

In the state shown in FIG. 1, the bent portions at both ends of the jumper wire 5 are formed as shown in FIG.
Insert After the insertion, both ends of the jumper wire 5 are bent inward to prevent the jumper wire 5 from coming off.

Next, as shown in FIG. 4, a metal mark 8 is applied to the upper surface of the printed circuit board 1 and a cream solder 9 is printed.

In FIG. 6, reference numeral 9 denotes cream solder printed on the printed circuit board 1. The cream solder 9 is printed in a range including the holes 2A and 2B, the jumper wire 5, and the land 7. After printing the cream solder 9, hot air is applied to the upper surface side of the printed circuit board 1 to melt the cream solder 9 and solder the lands 7 and the jumper wires 5.

Next, the land 4 on the lower surface of the printed circuit board 1 and one end of the jumper wire 5 are soldered by passing the printed circuit board 1 through a solder dip tank. In FIG. 5, reference numeral 10 denotes solder attached by a solder dip. In this way, the lands 7 on the upper surface of the printed circuit board 1 and the lands 4 on the lower surface are electrically connected via the jumper wires 5.

In the above embodiment, the lands 7 on one surface of the printed circuit board 1 and the jumper wires 5 are soldered by reflow, and the lands 4 on the other surface of the printed circuit board 1 and the jumper wires 5 are soldered. Is performed by solder dip,
This eliminates the possibility of removing the solder of the portion soldered by reflow during the solder dipping, and has the advantage that the connection between the lands can be reliably performed.

Further, as in the above embodiment, the position of the land 7 formed between the holes on the upper surface of the printed circuit board is on the side of the hole 2B different from the hole 2A to be soldered by the dip. Since the distance becomes longer, even if the printed circuit board 1 expands and contracts due to a temperature change, the expansion and contraction of the jumper wire 5 can absorb the expansion and contraction of the printed circuit board 1, and stress is less likely to be applied to the soldered portion. In addition, cracks are not generated in the soldered portion.

[0018]

As described above, according to the present invention, the first land is formed between the holes on one surface of the substrate, and the second land is formed on the edge of the hole on the other surface of the substrate. Forming and connecting the conductive wire and the first land each having an end inserted into the hole by reflow soldering, and connecting the conductive wire and the second land with a solder dip;
This has the advantage that the lands formed on both sides of the printed circuit board can be reliably connected by conductive wires.

[Brief description of the drawings]

FIG. 1 is a perspective view of a printed circuit board before a jumper wire is inserted according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the printed circuit board according to the first embodiment.

FIG. 3 is a perspective view of the printed circuit board after a jumper wire is inserted in the first embodiment.

FIG. 4 is a top view of the printed circuit board in a state where a metal mask is arranged in Embodiment 1;

FIG. 5 is a cross-sectional view of the printed circuit board after soldering the jumper wires according to the first embodiment.

FIG. 6 is a top view of a printed circuit board on which cream solder is printed in the first embodiment.

FIG. 7 is a sectional view of a conventional printed circuit board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2A, 2B hole 4 Land 5 Conductive wire (jumper wire) 7 Land 8 Metal mask 9 Cream solder 10 Solder

Claims (3)

[Claims] 1. A substrate having at least a pair of holes formed therein, a first land formed between the pair of holes on one surface of the substrate, and an edge of one hole on the other surface of the substrate. A second land formed on the portion, and conductive wires having both ends inserted into the holes, respectively, and connecting the first land and the conductive wire by reflow soldering; A printed circuit board formed by connecting an end of the conductive wire with a solder dip. 2. The method according to claim 1, wherein the position of the first land formed between the pair of holes on the other surface of the substrate is formed near another hole different from the hole connected by the solder dip. Printed board. 3. A step of inserting an end of a conductive wire into each hole of the substrate having at least a pair of holes formed therein, and a first step formed between the holes of the pair of holes on one surface of the substrate. A step of printing cream solder in a range including the land, a step of applying hot air to reflow solder the conductive wire and the first land, and a step of applying a solder paste to the edge of one hole on the other surface of the substrate. Connecting the formed second land and the end of the conductive wire through a solder dipping bath.