JPH06152092A - Surface-mount type printed circuit board assembly - Google Patents

Abstract

PURPOSE:To provide a surface-mount type printed circuit board assembly which can constantly and positively perform electrical connection with electronic parts to be mounted by soldering. CONSTITUTION:A solder 8 is adhered to a recessed surface electrode 4 in semi- cylindrical shape which is obtained by dividing the through hole of a printed circuit board 3 into two portions in the state where it is filled into the recessed part surrounded by the recessed surface electrode 4. Namely, the printed circuit board 3 is cut so that the through hole where the solder 8 is filled is cut into two portions. In the printed circuit board assembly 1 in this configuration, if a parent printed circuit board 10 and the printed circuit board assembly 1 are overlapped and are introduced into reflow when mounting on the parent printed circuit board 10, the solder 8 on the recessed electrode 4 of the printed circuit board assembly 1 is melted and is adhered on a land 11 of the parent printed circuit board 10, thus constantly and positively performing electrical connection with the parent printed circuit board 10 where it is mounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a semi-cylindrical concave electrode obtained by dividing a through hole of a printed circuit board on an end surface of the printed circuit board, and is used for electronic parts such as other printed circuit boards. The present invention relates to a surface mount type substrate assembly mounted on a surface.

[0002]

2. Description of the Related Art FIG. 5 is a perspective view of an essential part of an example of a conventional surface mount type substrate assembly of this type, and shows a state in which it is stacked on another printed circuit board which is a mounting destination. See also FIG.
FIG. 7A is a plan view illustrating a method for manufacturing the conventional surface mount board assembly.

As shown in FIG. 5, the surface mount type substrate assembly 2 is constructed by providing a plurality of semi-cylindrical concave electrodes 4 on an end surface of a printed circuit board 3. Each concave electrode 4 is connected to a predetermined wiring 5 on the substrate 3.

In order to manufacture the board assembly 2 having such a structure, as shown in FIG. 6, a plurality of through holes 6 are formed in a row in the printed board 3, and the board 3 is formed on the inner surface of each through hole 6. A conductive layer 7 connected to the predetermined wiring 5 is formed in advance. After that, this printed circuit board 3
Each through hole 6 is cut so as to be divided into two. As a result, each of the bisected through holes 6 becomes a semi-cylindrical concave electrode 4 to form the substrate assembly 2 having the above-described configuration.

In this board assembly 2, each of the concave electrodes 4 has a plurality of connecting portions provided on the surface of another electronic component, for example, another printed board 10 (hereinafter referred to as the parent board 1).
Soldered to a plurality of lands 11 (referred to as 0) to be mounted on the parent board 10 which is an electronic component thereof. At this time, since solder is not attached to each concave electrode 4 of the substrate assembly 2, solder is attached in advance to each land 11 of the mounting-destination parent board 10 by printing, and each land 11 is attached to each land 11. In the state where the lower end portion of the concave electrode 4 is in contact with the parent substrate 10 and the substrate assembly 2, the parent substrate 10 and the substrate assembly 2 are stacked and put into reflow soldering.

[0006]

However, when the solder is attached to the lands 11 of the mounting-destination parent board 10 by printing, if the pitch between the lands 11 is small, there is a risk that a solder bridge will occur. In addition, a sufficient amount of solder cannot be attached to the land 11. Also the parent board 1
Even when a large number of components are mounted on the surface with a fine pitch, it is necessary to reduce the amount of solder and prevent the solder bridge, so that the plate for solder printing must be thin, and therefore, the land 11 has a sufficient amount. Cannot attach solder. When a sufficient amount of solder is not adhered to the land 11 of the mounting-destination parent board 10 as described above, a small amount of solder on the land 11 is erected on the land 11. It is difficult to attach the concave electrode 4 to the concave electrode 4, so that the concave electrode 4 of the substrate assembly 2 and the land 11 of the parent substrate 10 cannot be reliably soldered.

That is, the conventional surface mount type substrate assembly 2
However, if a sufficient amount of solder is not attached to the connection part of the mounting destination electronic component, there is a problem that the electrical connection with the mounting destination electronic component cannot be reliably performed.

The present invention has been made in order to solve such a problem, and provides a surface mount type substrate assembly which can always surely make an electrical connection with an electronic component of a mounting destination by soldering. The purpose is to

[0009]

In order to achieve the above object, in the surface mount type substrate assembly according to the present invention, solder is attached to the concave electrode while being filled in the concave portion surrounded by the concave electrode. .

[0010]

In the board assembly having the above structure, when the electronic parts and the board assembly are superposed on each other when they are mounted on the surface of another electronic part, the solder on the concave electrode of the board assembly is put into the reflow. It melts and adheres to the connection part of the electronic component at the mounting destination. As a result, the electrical connection with the electronic component of the mounting destination can always be ensured.

[0011]

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

In the drawings of the embodiment, the same parts as those in the drawings of the conventional example shown in FIGS. 5 and 6 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 is a perspective view of an essential part of a surface mount type substrate assembly according to the present invention, showing a state in which the surface mount type substrate assembly is stacked on another printed circuit board which is a mounting destination. FIG. 2 is a partially enlarged view of FIG.

As shown in the drawing, the difference from the conventional example of the surface mount type substrate assembly 1 is that the semi-cylindrical concave electrode 4 provided on the end face of the printed circuit board 3 of the substrate assembly 1 is
The point is that the solder 8 is attached while being filled in the concave portion surrounded by the concave electrode 4.

In the substrate assembly 1 having the above structure, the solder 8 is attached to the concave electrode 4 as described above.
When this board assembly 1 is mounted on the surface of another electronic component, for example, on another printed board 10 (hereinafter referred to as the parent board 10), the land 11 of the parent board 10 at the mounting destination is mounted.
Even if the solder 8 is not attached to the concave electrode 4 in advance,
Can be soldered to the land 11. That is, when the substrate assembly 1 and the parent substrate 10 are overlapped and put into reflow with the lower end portion of the concave electrode 4 and the land 11 being in contact with each other, the solder 8 on the concave electrode 4 of the substrate assembly 1 is melted. Attach to land 11. In this way, the solder 8 attached to the concave electrode 4 standing on the land 11 of the parent substrate 10 is land 1
The concave electrode 4 and the land 11 can be reliably soldered by melting and adhering on the surface 1. Moreover, at this time, the solder 8 on the concave electrode 4 of the substrate assembly 1 is
Are attached in a state of being filled in the concave portion surrounded by the concave electrode 4, so that the concave electrode 4 and the land 1 are attached.
It is possible to obtain a sufficient amount of solder necessary for reliably soldering 1 and 1 according to the shape and area of the concave electrode 4.

Therefore, according to the above substrate assembly 1,
The pitch between the lands 11 of the mounting parent board 10 is fine,
Alternatively, even when a large number of components are mounted on the parent board 10 at a fine pitch and a sufficient amount of solder cannot be attached to the land 11, electrical connection by soldering to the parent board 10 is possible. Can always be done reliably. Further, since it is possible to deal with the mother board 10 having a fine pitch between the lands 11 such that a sufficient amount of solder cannot be attached, the end surface of the printed board 3 of this board assembly 1 can be finely pitched. Many concave electrodes 4
Can be provided, and the substrate assembly 1 itself can be downsized. Furthermore, the pitch between the lands 11 can be formed finely with respect to the parent board 10 of the mounting destination, and at the same time, the lands 11 can be formed.
The area of can also be reduced according to the width of the concave electrode 4 of the substrate assembly 1, so that the mounting area can be increased.

The substrate assembly 1 is used as a parent substrate 10.
If the solder is attached to the land 11 of the parent board 10 by printing even when mounted on the parent board 10, the concave electrode 4 of the board assembly 1 and the land 11 of the parent board 10 can be more reliably soldered. Can be

In order to manufacture the substrate assembly 1 having the above-mentioned structure, as shown in the plan view of FIG. 3, the conductive layer 7 is formed on the inner surfaces of the plurality of through holes 6 formed in a row on the printed circuit board 3, and further the conductive layer 7 is After filling the through holes 6 with the solder 8, the substrate 3 may be cut so as to divide each through hole 6 into two.

In order to fill the solder 8 into the through holes 6 of the printed circuit board 3, when the solder leveler is performed on the electrolytic copper plated printed circuit board 3, one of the openings of the through hole 6 is opened. It is sufficient to prevent the solder accumulated in the through hole 6 from being removed by blowing air by closing the hole. Alternatively, the solder 8 may be filled in the through hole 6 during the soldering process.

In the above-described manufacturing method, the printed board 3 is cut after the solder 8 is filled in the through holes 6, but
As shown in the plan view of the main part of FIG. 4, after the printed circuit board 3 is cut to form the concave electrodes 4, solder is also applied to the concave electrodes 4 at the stage of attaching solder for mounting components on the substrate 3. It is also possible to manufacture by making it adhere.

In this way, the substrate assembly is
It is very useful as an electronic component that can be reliably soldered to the parent board 10 even at a fine pitch.

[0022]

As described above, according to the surface mount type substrate assembly of the present invention, even when it is impossible to adhere a sufficient amount of solder to the connection part of the electronic component of the mounting destination, The electrical connection with the electronic component of the mounting destination can always be ensured.

Further, since it is possible to cope with an electronic component having a fine pitch between the connecting portions such that a sufficient amount of solder cannot be attached to the connecting portions, the end face of the printed circuit board of this board assembly is It is possible to provide a large number of concave electrodes at a fine pitch, and it is also possible to miniaturize the substrate assembly itself.

Further, with respect to the electronic component to be mounted, the pitch between the connection portions of the electronic component can be formed finely, and at the same time, the area of the connection portion is adjusted to the width of the concave electrode of this substrate assembly. Therefore, the mounting area can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a surface-mounted board assembly according to an embodiment of the present invention, showing a state in which the surface-mounted board assembly is stacked on another printed board which is a mounting destination.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a plan view illustrating the method of manufacturing the surface mount type substrate assembly according to the embodiment.

FIG. 4 is a plan view of a principal part for explaining another method of manufacturing the surface mount type substrate assembly in the example.

FIG. 5 is a perspective view of a main part of a surface mount board assembly in a conventional example, showing a state in which the surface mount board assembly is stacked on another printed board which is a mounting destination.

FIG. 6 is a plan view illustrating a method of manufacturing a surface-mounted board assembly according to a conventional example.

[Explanation of symbols]

 1 Surface Mounted Board Assembly 3 Printed Circuit Board 4 Concave Surface Electrode 6 Through Hole 8 Solder

Claims (1)

[Claims] 1. A surface mount type substrate assembly comprising a semi-cylindrical concave electrode obtained by dividing a through hole of the printed circuit board on an end face of the printed circuit board, wherein the semi-cylindrical concave electrode is formed. Is a surface mount type substrate assembly characterized in that solder is applied in a state of being filled in a concave portion surrounded by the concave electrode.