JP4471917B2 - Solder connection repair method in composite substrate equipment - Google Patents

Description

  The present invention relates to a composite substrate device configured by electrically connecting substrates, and particularly to application in a mobile device.

  In recent years, mobile information devices typified by mobile phones have been further reduced in size, weight, and thickness, and ingenuity is required. Therefore, there is a demand for an electronic circuit device in which individual components themselves are reduced in size and weight, the pattern accuracy of the circuit board is miniaturized, and high-density mounting on the board is pursued. Most of these pursuits are two-dimensional efforts on a circuit board.

  However, in reality, when considering the overall dimensions, design, and multi-model deployment of mobile information devices, there is a need for three-dimensional inter-module connection and mounting structure, such as utilization and storage of space in the chassis. Is growing.

  Conventionally, in this type of electronic circuit device, the density of component mounting is increased by reducing the size of components, reducing the wiring pitch, increasing the number of stacked circuit boards, and connecting multiple circuit boards. It was realized.

For example, a method for connecting a plurality of circuit boards in the vertical direction is described in the following (Patent Document 1). For example, as shown in FIG. 3A, a module circuit board 1 on which surface-mounted components or semiconductor bare chips are mounted is electrically connected to a base printed board 2 on which component mounting similar to that of the module circuit board 1 is performed. It is inserted into the other end of the connected connection pin 3 and then the wiring pattern 4 of the module circuit board 1 and the connection pin 3 are connected by solder 6 as shown in FIG. The base printed circuit board 2 and the module circuit board 1 are connected by a plurality of connection pins 3. The plurality of connection pins 3 are intermediate connection bodies embedded in a frame block 11 made of an insulating material as shown in FIG. In the actual assembly process, the intermediate connection body 5 is sandwiched between the base printed board 2 and the module circuit board 1, and each connection pin 3 is connected to the circuit by soldering with the solder 6. Connected to pattern 4.
JP 9-121079 A

  However, at present, the workability of repair for replacing a failed module circuit board 1 with a normal operation product is poor. Specifically, when repairing, as shown in FIG. 3C, the heating means 7 such as a solder rivet is pressed against the tip of the connection pin 3 to melt the solder 6, and the solder 6 is melted. During the state, the defective module circuit board 1 is lifted and removed from the connection pins 3 as indicated by phantom lines.

  When the solder 6 is melted, the heat transfer path is such that heat is transferred from the heating means 7 to the tip of the connection pin 3, and the heat is transferred to the base end of the connection pin 3, so that the temperature of the solidified solder is increased. Ascending gradually, the entire solder 6 is melted and the defective module circuit board 1 can be removed. What is illustrated as the heating means 7 is a jig having a convex portion that abuts against a plurality of connection pins 3, and the jig is heated with a soldering iron to connect the module substrate 1 and all the connection pins 3. It is necessary to melt the solder 6 in the meantime, but it takes time to melt the solder, and repair workability is poor.

SUMMARY OF THE INVENTION An object of the present invention is to provide a solder connection repair method in a composite substrate device that can be expected to have better repair workability than before.

A repair method for solder connection in a composite board device of the present invention includes an intermediate connection body that is interposed between a base printed board and a module circuit board and in which a plurality of connection pins are embedded. Connected to the circuit pattern constructed on the base printed board, the other ends of the plurality of connection pins are inserted into through holes formed in the module circuit board from the back surface of the module circuit board, and the tips thereof are inserted into the through holes. A composite substrate in which the other end of the plurality of connection pins is solder-connected to a circuit pattern built on the module circuit board by mounting the module circuit board on the base printed board A method for repairing a solder connection in an apparatus, wherein the through hole is formed from an opening at an end portion on the side where the other ends of the plurality of connection pins are inserted. The opening on the opposite side is formed to be large, and the cross-sectional shape of the through hole has a shape along the outer shape of the tip of the heating means, and the heating means is directly on the solder surface inside the through hole. The solder is melted by pressing, and the module circuit board is lifted from the side of the base printed board while the solder is in a molten state, and is extracted from the plurality of connection pins .

The cross-sectional shape of the through hole is a conical shape along the outer shape of the tip of the heating means .

  According to the present invention, since the tip of the other end of the connection pin is embedded in the solder inside the through hole, a heating means such as a solder rod can be directly pressed against the solder inside the through hole. The heat from the heating means is transmitted to the solder without passing through the connection pins to start melting, and all the solder between the connection pins and the second substrate can be melted in a shorter time than before. .

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 (a) shows a composite substrate apparatus that has been soldered.
5A is an intermediate connector in which a plurality of connection pins 3A are embedded in an insulating material in the same manner as the intermediate connector 5 shown in FIG. 4, and 1A is a module as a second substrate on which surface-mounted components, semiconductor bare chips, etc. are mounted A circuit board 2 is a base printed board as a first board on which component mounting similar to that of the module circuit board 1A is performed. In the actual assembly process, the intermediate connection body 5A is sandwiched between the base printed board 2 and the module circuit board 1A, and each connection pin 3A is connected to the circuit pattern 4 by soldering with the solder 6.

  In this embodiment, the length of the connection pin 3A and the shape of the through hole 8 formed in the module circuit board 1A are different from the conventional one. Specifically, the connection pin 3A protrudes from the opening at the end on the side where the connection pin 3A is inserted into a portion without the through hole 8, and the tip 9 at the other end of the connection pin 3A is inside the through hole 8. The connection pin 3A does not protrude from the upper surface of the module circuit board 1A. The through hole 8 is formed so that the opening S2 on the opposite side is larger than the opening S1 on the end on the side where the connection pin 3A is inserted.

  Since it comprised in this way, in the case of repair, as shown in FIG.1 (b), the heating means 7, such as a soldering iron, can be directly pressed on the surface of the solder 6 inside the said through-hole 8. FIG. . Thus, the heat from the heating means 7 is not transmitted via the connection pin 3A as in the prior art, but the heat from the heating means 7 is directly transmitted to the solder 6 and is shown in FIG. 1 (c). Thus, melting can be started, and all the solder 6 between the connection pins 3A and the module substrate 1A can be melted in a shorter time than in the past. Then, as in the prior art, while the solder 6 is in a molten state, the defective module circuit board 1A is lifted from the base printed board 2 side and removed from the connection pins 3A.

Furthermore, when the through-hole 8 is conical and has a shape along the outer shape of the tip of the heating means 7, the heat of the heating means 7 is further transmitted.
In FIG. 1, the end surfaces of the plurality of connection pins 3A are formed flat. However, the connection pins 3A can be connected by sharpening the tip as shown in FIG. 2 (a) or by attaching a radius as shown in (b). By tapering the pins 3A, the module circuit board 1A can be easily inserted into the connection pins 3A. Particularly, when there are a plurality of pins in one unit, the module circuit board 1A is slightly inserted at the time of insertion. The displacement is also automatically corrected following the shape of the tip of the connection pin 3A. The connection pin 3A is easier to insert than a flat end surface, and the workability during assembly and soldering is improved.

  The composite substrate device of the present invention can be widely used in various mobile devices such as mobile phones and the like that are required to be highly functional, multifunctional and compact.

The expanded sectional view of the embodiment of the composite substrate device of the present invention The expanded sectional view of the important section of another embodiment Expanded sectional view of a conventional composite substrate device The perspective view of the intermediate connection body of the conventional example

Explanation of symbols

1A Module circuit board (second board)
2 Base printed circuit board (first board)
3A connection pin 4 circuit pattern 5A intermediate connection body 6 solder 8 through hole 9 tip of connection pin 3A S1 opening of through hole 8 on the side where the connection pin 3A is inserted S2 penetration opposite to the side where the connection pin 3A is inserted Opening of hole 8

Claims (2)

An intermediate connection body that is interposed between a base printed board and a module circuit board and has a plurality of connection pins embedded therein, and connects one end of the plurality of connection pins to a circuit pattern built on the base printed board, The other end of the plurality of connection pins is inserted into a through hole formed in the module circuit board from the back surface of the module circuit board, and the tip thereof is embedded in the solder inside the through hole, thereby the plurality of connection pins. A solder connection repair method in a composite board device in which the other end of the module circuit board is solder-connected to a circuit pattern constructed on the module circuit board and the module circuit board is mounted on the base printed board,
The through hole is formed such that an opening on the opposite side is larger than an opening on the end where the other end of the plurality of connection pins is inserted, and the cross-sectional shape of the through hole is the outer shape of the tip of the heating means. Has a shape along
By directly pressing the heating means against the surface of the solder inside the through hole, the solder is melted, and the module circuit board is lifted from the base printed circuit board while the solder is in a molten state. Remove from multiple connection pins
A method for repairing solder connection in a composite substrate apparatus. The cross-sectional shape of the through hole is a conical shape along the outer shape of the tip of the heating means.
The method for repairing solder connection in the composite substrate device according to claim 1.

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