JP2006165048A - Electronic circuit board assembly and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic circuit board assembly which is capable of being manufactured inexpensively and simply, and which can be reduced in size and is easy to repair. <P>SOLUTION: The external electrode 40a of an electronic component 4a and a convex conductive pin 5 are connected to a plurality of conductive layers 2a, connected to printed wiring of a printed wiring board 1a with the aid of a solder 6a. Further, the external electrode 40b of an electronic component 4b and a concave conductive pin 8 are connected with a plurality of conductive layers 2b, connected to printed wiring of a printed wiring board 1b with a solder 6b. Then, the convex conductive pin 5 and the concave conductive pin 8 are fitted to each other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic circuit board assembly in which a plurality of electronic circuit wiring boards are overlapped so as to be electrically connected via conductive pins, and a method for manufacturing the same.

  Along with miniaturization and high functionality of electronic devices, miniaturization and multilayering of printed wiring boards built in electronic devices and miniaturization of electronic components mounted on the printed wiring boards are remarkably progressing. For this reason, in the conventional electronic component mounting method in which electronic components are mounted on both the front surface and the back surface of one printed wiring board, there is a problem that it is difficult to mount all the electronic components.

  On the other hand, in Patent Document 1 to be described later, in order to solve the above-described problem, a method of easily and surely electrically connecting electronic circuit boards having electronic components mounted on a printed wiring board is proposed. . Hereinafter, an electronic circuit board assembly in which electronic circuit boards shown in Patent Document 1 are overlapped will be described.

When the first electronic circuit board and the second electronic circuit board are overlapped, through holes are provided at positions facing each other on the first electronic circuit board and the second electronic circuit board. The through-hole has a mortar shape in which the opening on the front surface of each of the first and second electronic circuit boards is larger than the opening on the back surface of each of the first and second electronic circuit boards. In order to connect the first electronic circuit board and the second electronic circuit board, first, solder paste is filled in the through holes. Next, pin contacts formed of a material having high thermal conductivity are inserted into each through hole in a heated state. Thereafter, the melted solder paste is cured. As a result, the first electronic circuit board and the second electronic circuit board are electrically and mechanically connected to each other.
Japanese Patent Laid-Open No. 9-270575

  In the conventional method of connecting the first electronic circuit board and the second electronic circuit board, pin contacts are inserted so as to penetrate through holes. Therefore, the pin contact remains in a state of protruding from the through hole. Therefore, electronic components cannot be mounted on both the front and back surfaces of the first and second electronic circuit boards on the extension line of the through hole. Therefore, the electronic circuit board assembly in which the first and second electronic circuit boards are combined cannot be reduced in size.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a downsized electronic circuit board assembly.

  An electronic circuit board assembly of the present invention includes a first printed wiring board having a first printed wiring, a first electronic component electrically connected to the first printed wiring, and a first printed wiring. A convex conductive part electrically connected, a second printed wiring board having a second printed wiring, a second electronic component electrically connected to the second printed wiring, and a second printed circuit And a concave conductive portion electrically connected to the wiring. Further, the convex conductive portion and the concave conductive portion are fitted.

  According to the above configuration, there is a space for mounting electronic components on the back side of the convex conductive part of the first printed wiring board and the back side of the concave conductive part of the second printed wiring board. The assembly can be downsized.

  Further, the convex conductive portion may include a first conductive layer connected to the first printed wiring and a convex conductive pin formed on the first conductive layer. The concave conductive portion may include a second conductive layer connected to the second printed wiring and a concave conductive pin formed on the second conductive layer. Furthermore, it is desirable that each of the convex conductive pin and the concave conductive pin is made of a single metal. According to this configuration, the convex conductive pin and the concave conductive pin can be easily formed. Moreover, it is desirable that each of the convex conductive pin and the concave conductive pin is formed on the non-conductive member by electroless plating. This configuration also facilitates the formation of the convex conductive pins and the concave conductive pins.

  In the method for manufacturing an electronic circuit board assembly of the present invention, a first conductor layer and a second conductor layer that are electrically connected to each other via a printed wiring are formed on a first printed wiring board. Next, a first solder paste is formed on the first conductor layer, and a second solder paste is formed on the second conductor layer. Thereafter, the external electrode of the first electronic component is placed on the first conductor layer, and the convex conductive pin is placed on the second conductor layer. Next, the first printed wiring board is heated to melt the first and second solder pastes. Thereafter, the first conductor layer and the external electrode of the first electronic component are soldered together, and the second conductor layer and the convex conductive pin are soldered.

  On the other hand, a third conductor layer and a fourth conductor layer electrically connected to each other through the printed wiring are formed on the second printed wiring board. Next, a third solder paste is applied on the third conductor layer, and a fourth solder paste is applied on the fourth conductor layer. Thereafter, the external electrode of the second electronic component is placed on the third conductor layer, and the concave conductive pin is placed on the fourth conductor layer. Next, the second printed wiring board is heated to melt the third and fourth solder pastes. Thereafter, the third conductor layer and the external electrode of the second electronic component are soldered together, and the fourth conductor layer and the concave conductive pin are soldered. Finally, the convex conductive pin and the concave conductive pin are fitted together.

  According to said method, the above-mentioned electronic circuit board aggregate | assembly can be formed easily.

  According to the present invention, there is a space for mounting electronic components on the back side of the convex conductive part of the first printed wiring board and the back side of the concave conductive part of the second printed wiring board. The body can be miniaturized. In addition, even if a failure occurs in one of the two electronic circuit boards constituting the electronic circuit board assembly, the failure is caused by releasing the fitting between the convex conductive portion and the concave conductive portion. It is possible to easily repair or replace the electronic circuit board. Therefore, it is possible to avoid an uneconomic situation in which all of the electronic circuit board assembly is discarded due to a defect occurring in one of the two electronic circuit boards.

  Hereinafter, an electronic circuit board assembly 7 according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the electronic circuit board assembly 7 of the present embodiment includes a printed wiring board 1a and a printed wiring board 1b. A plurality of conductor layers 2a are provided on the printed wiring board 1a. A plurality of conductor layers 2b are provided on the printed wiring board 1b.

  Solder 6a is provided on each of the plurality of conductor layers 2a. A solder 6b is provided on each of the plurality of conductor layers 2b. The external electrodes 40a and the convex conductive pins 5 of the electronic component 4a are connected to the plurality of conductor layers 2a by the plurality of solders 6a. Further, the external electrodes 40b and the concave conductive pins 8 of the electronic component 4b are connected to the plurality of conductor layers 2b by the plurality of solders 6b.

  The conductor layers 2a are electrically connected to each other by a printed wiring (not shown) provided on the printed wiring board 1a. The conductor layers 2b are electrically connected to each other by printed wiring provided on the printed wiring board 1b.

  In FIG. 1, the tip of the convex conductive pin 5 has a conical shape, and the concave conductive pin 8 has a conical recess corresponding to the tip of the conical shape described above. Actually, it is like the concave conductive pin 8 and the convex conductive pin 5 described with reference to FIG.

  That is, the tip of the convex conductive pin 5 is wider than the base, and the concave conductive pin 8 has a structure in which the portion where the tip of the convex conductive pin 5 is widened is difficult to come off at the tip. Yes. When the convex conductive pin 5 is inserted into the concave conductive pin 8, the opening at the tip of the concave conductive pin 8 is widened by elastic deformation. Moreover, each of the concave conductive pins 8 and the convex conductive pins 5 may be made of a single metal, or a metal film formed by electroless plating on a nonconductive member.

  The method for manufacturing the electronic circuit board assembly 7 shown in FIG. 1 is as follows.

  First, as shown in FIG. 3, a plurality of conductor layers 2a are formed on a printed wiring board 1a. Next, the solder paste 3 is supplied onto each of the plurality of conductor layers 2a. Thereafter, as shown in FIG. 4, the external electrodes 40 a and the convex conductive pins 5 of the electronic component 4 a are placed on the plurality of conductor layers 2 a via the solder paste 3. The convex conductive pin 5 is formed on the nonconductive member by electroless plating.

  Next, the printed wiring board 1a having the structure shown in FIG. 4 is heated in a heating apparatus such as a reflow furnace. As a result, the solder paste 3 is melted, and each of the external electrode 40a and the convex conductive pin 5 of the electronic component 4a and the corresponding conductor layer 2a are joined by the solder 6a, and the electronic circuit board 7a as shown in FIG. Is obtained.

  On the other hand, a plurality of conductor layers 2b are formed on the printed wiring board 1b separately from the method for manufacturing the electronic circuit board 7a. Next, a solder paste is supplied onto each of the plurality of conductor layers 2b. Thereafter, the electronic component 4b and the concave conductive pin 8 are placed on the plurality of conductor layers 2b supplied with the solder paste. The concave conductive pin 8 is formed on the nonconductive member by electroless plating.

  Next, in the heating apparatus such as a reflow furnace, the above-described printed wiring board 1b is heated in the same manner as the manufacturing method of the electronic circuit board 7a. As a result, the solder paste is melted, and each of the external electrode 40b and the concave conductive pin 8 of the electronic component 4b and the corresponding conductor layer 2b are joined by the solder 6b, and an electronic circuit board 7b as shown in FIG. 6 is obtained. It is done.

  Thereafter, the electronic circuit board 7a and the electronic circuit board 7b are overlaid in an aligned state, and the convex conductive pins 5 and the concave conductive pins 8 are fitted as shown in FIG. Thereby, the electronic circuit board assembly 7 shown in FIG. 1 is formed.

  As a result of conducting the electrical test of the electronic circuit board assembly 7 as described above, it was found that desired electrical characteristics were obtained. The electronic circuit board assembly 7 was subjected to 2000 cycles of a temperature cycle test of −40 ° C. (30 minutes) to 125 ° C. (30 minutes). As a result of observing the electronic circuit board assembly 7 after the test, almost no cracks were found in the solder joint between the convex conductive pin 5 and the conductor layer 2a and the solder joint between the concave conductive pin 8 and the conductor layer 2b. As a result, it was found that sufficient bonding reliability was obtained.

  According to the electronic circuit board assembly 7 of the present embodiment described above, the electronic components 4a and 4b are placed on the back side of the convex conductive pins 5 of the electronic circuit board 7a and the back side of the concave conductive pins 8 of the electronic circuit board 7b, respectively. Since there is a space for mounting, the electronic circuit board assembly 7 can be reduced in size. In addition, even if a problem occurs in either of the electronic circuit boards 7a and 7b, the assembly of the defective electronic circuit boards is obtained by releasing the fitting between the convex conductive pins 5 and the concave conductive pins 8. The body 7 can be easily repaired or replaced. Therefore, it is possible to avoid an uneconomic situation in which the entire electronic circuit board assembly 7 is discarded due to a problem that occurs only in one of the electronic circuit boards 7a and 7b.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a side view of the electronic circuit board assembly of an embodiment of the invention. It is an expanded sectional view of the fitting part of the convex conductive pin of the electronic circuit board assembly of an embodiment of the invention, and a concave conductive pin. It is a figure for demonstrating the manufacturing method of the electronic circuit board assembly of embodiment of this invention. It is a figure for demonstrating the manufacturing method of the electronic circuit board assembly of embodiment of this invention. It is a figure for demonstrating the manufacturing method of the electronic circuit board assembly of embodiment of this invention. It is a figure for demonstrating the manufacturing method of the electronic circuit board assembly of embodiment of this invention.

Explanation of symbols

  1a printed wiring board, 1b printed wiring board, 2a conductor layer, 2b conductor layer, 3 solder paste, 4a, 4b electronic component, 5 convex conductive pin, 6 solder, 7 electronic circuit board assembly, 7a electronic circuit board, 7b Electronic circuit board, 8 concave conductive pins, 40a, 40b external electrodes.

Claims (4)

A first printed wiring board having a first printed wiring;
A first electronic component electrically connected to the first printed wiring;
A convex conductive portion electrically connected to the first printed wiring;
A second printed wiring board having a second printed wiring;
A second electronic component electrically connected to the second printed wiring;
A concave conductive portion electrically connected to the second printed wiring,
An electronic circuit board assembly in which the convex conductive portion and the concave conductive portion are fitted. The convex conductive portion includes a first conductive layer connected to the first printed wiring and a convex conductive pin formed on the first conductive layer,
The concave conductive portion includes a second conductive layer connected to the second printed wiring and a concave conductive pin formed on the second conductive layer,
The electronic circuit board assembly according to claim 1, wherein each of the convex conductive pins and the concave conductive pins is made of a single metal. The convex conductive portion includes a first conductive layer connected to the first printed wiring and a convex conductive pin formed on the first conductive layer,
The concave conductive portion includes a second conductive layer connected to the second printed wiring and a concave conductive pin formed on the second conductive layer,
The electronic circuit board assembly according to claim 1, wherein each of the convex conductive pins and the concave conductive pins is formed by electroless plating on a non-conductive member. Forming a first conductor layer and a second conductor layer electrically connected to each other via a printed wiring on a first printed wiring board;
Applying a first solder paste on the first conductor layer and applying a second solder paste on the second conductor layer;
Placing the external electrode of the first electronic component on the first conductor layer, and placing a convex conductive pin on the second conductor layer;
The first printed wiring board is heated to melt the first and second solder pastes, and the first conductor layer and the external electrode of the first electronic component are soldered together, and the second Soldering the conductor layer and the convex conductive pin,
Forming a third conductor layer and a fourth conductor layer electrically connected to each other via a printed wiring on a second printed wiring board;
Applying a third solder paste on the third conductor layer and applying a fourth solder paste on the fourth conductor layer;
Placing the external electrode of the second electronic component on the third conductor layer, and placing a concave conductive pin on the fourth conductor layer;
The second printed wiring board is heated to melt the third and fourth solder pastes, and the third conductor layer and the external electrode of the second electronic component are soldered together. Soldering the conductor layer and the concave conductive pin,
A method for manufacturing an electronic circuit board assembly, comprising the step of fitting the convex conductive pin and the concave conductive pin.

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