JPH0752790B2 - Parent-child board mounting method - Google Patents

Description

The present invention relates to a method of mounting a child printed board (child board) on a parent printed board (parent board).

[Outline of Invention]

There are two methods of mounting the child board on the parent board: a method of using a connector and a method of directly soldering the child board to the parent board. The present invention relates to the latter, in which the child board is inserted into the slit formed in the parent board and the terminals of both are soldered. However, since various terminals are lined up in the slit of the parent board, they are short-circuited. Therefore, the slit is not conventionally a through hole, and fillet soldering is performed on one side of the parent board for connection between both boards. It was Therefore, it was extremely insufficient in terms of soldering reliability. In addition, it was necessary to separately provide through holes to electrically connect the front and back of the parent board.

This time, we tried to solve these problems such as soldering strength, electrical connection between the front and back of the main board, etc. by cutting the through hole provided in the slit according to the terminal.

[Conventional technology]

In the prior art, as shown in FIG. 5, the terminal portion 21 of the child board 2 is inserted into the slit 12 provided in the parent board 1 ', and the pattern 11' and the terminal portion 21 on the back surface of the parent board 1'are shown in FIG. Like solder 31
It was something to connect with.

However, in this method, as shown in FIG. 6, the solder 31 can be attached only to one side, and when stress is applied to the child board 2, the force is applied to the solder 31, but so-called fillet soldering is performed. Therefore, there was a drawback that the solder was easily cracked. On the other hand, since the electrical connection between the front surface and the back surface of the parent board 1'is also divided by the slit, it is necessary to provide a large number of through holes 15 as shown in FIG.

[Problems to be Solved by the Invention]

The above-mentioned conventional techniques have drawbacks such as weak soldering connection strength and the need to provide many through holes in the vicinity of the slits. The present invention aims to eliminate these drawbacks.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention temporarily forms the slits of the parent board 1 by through-hole plating as shown in FIG.
Each terminal is cut to form a partial through hole, and a protrusion is formed in the slit as shown in FIG.

[Action]

By forming the slit 12 as a partial through hole as shown in FIGS. 1 and 2, the side wall of the slit 12 of the parent board 1 is covered with a conductive metal (such as Cu) 14, so that the child board 2 If the terminal portion 21 of is inserted, solder connection can be performed inside and above the slit. The front and back patterns of the parent board 1 are also connected by the conductor metal 14 through the slit 12. Further, when the child board is inserted into the slit as shown in FIGS. 7 and 8, the child board is held by the parent board by the spring force of the protrusion of the parent board.

〔Example〕

 1 to 4 show an embodiment of the present invention.

That is, as shown in FIG. 1, the terminal portion 21 of the child board 2 is inserted into the slit portion 12 of the parent board 1. When the slit portion is enlarged, the terminal 11 becomes a through hole as shown in FIG. Thus, the main substrate 1 is connected across the front and back. On the other hand, a groove 13 is formed between each terminal 11,
14 is divided, and terminals 11 are not electrically connected (shorted) to each other. This is one in which the slit 12 periphery is once made into an elongated through hole as shown in FIG. 3 and the groove 13 is provided as shown in FIG. The groove 13 can be easily processed by a router, a press, or the like.

Next, this operation will be described.

FIG. 4 shows a parent board 1 and a child board 2 mounted as shown in FIG.
And a cross section, and both are electrically and mechanically integrated by solders 31 and 32. According to such a mounting method, the solder 31 is easily guided to the upper surface of the mother board by the through hole 14 and the terminal 21 and becomes 32. That is, the through hole 14 and the terminal 21 are also connected by solder. Thus, the parent board 1 and the child board 2 are firmly connected,
Soldering reliability is greatly improved. Further, since the pattern 11 on the front surface of the mother board and the pattern 11 '''on the rear surface are electrically integrated by the through hole 14, it is not necessary to provide another through hole and the mounting restrictions are reduced.

7 to 9 show another embodiment of the present invention.

FIG. 7 is a diagram showing a printed circuit board mounting method according to the present invention, in which the slit (width t ') 12 of the parent board 1 is inserted into the child board (plate thickness t).
2 is inserted and the terminal 21 of the child board 2 is connected to the corresponding terminal on the back surface of the parent board 1 by soldering.

FIG. 8 is a cross-sectional view showing the mounting of the one shown in FIG. 7. If t ′ <t in FIG. The formed protrusion 16 bends in this insertion direction. The spring force of the protruding portion 16 allows the child board 2 to be sufficiently fastened to the parent board 1, and even if the terminals 21 and the terminals provided on the back surface of the parent board 1 are soldered by the solder 33, the parent board 1 or the child board 2 The stress applied to the solder 33 is not directly applied to the solder 33. That is, the solder 33 is protected from the force applied to the parent board 1 or the child board 2. 9th
The figure shows the conventional method. That is, since there are only the slits 12 formed in the parent board 1, the board 2 cannot be inserted into the parent board 1 when t '<t. On the other hand, when t '> t, when stress is applied to the parent board or the child board 2 after soldering, a force is directly applied to the solder, which causes soldering failure. According to the present invention, such a problem can be solved.

〔The invention's effect〕

As described above, according to the present invention, as a result of soldering in the slit, the soldering connection reliability between the parent board 1 and the child board 2 is significantly improved. Further, since the conductor metal itself in the slit electrically connects the front and back of the parent board, it is not necessary to provide a special through hole, and the mounting space of the parent board is widened accordingly, and mounting restrictions are reduced. be able to. Further, since the child board is mechanically firmly held by the projection on the parent board, soldering failure does not occur even if stress is applied to the board after soldering.

[Brief description of drawings]

1 to 4 relate to the present invention, and FIG. 1 is a perspective view showing the concept of a method of mounting a parent-child board in which the slit portion of the parent board of the present invention is a partial through hole. 2 is an enlarged view of the slit portion of the parent board in FIG. 1, FIG. 3 is a perspective view showing a through hole forming method of the slit portion, FIG.
The figure is a view showing a cross section of what is mounted as shown in FIG. Fifth
FIG. 9 is a perspective view showing the concept of a conventional mounting method. Sixth
The figure is a view showing a cross section of what is mounted as shown in FIG. 7 to 8 are views showing another embodiment of the present invention. 1 is a parent substrate having the slit structure of the present invention, 2 is a child substrate, 11
1 is a terminal or pattern provided on the surface of 1; 11 '''is a terminal or pattern on the back surface; 12 is a slit; 13 is a groove provided in the slit; 14 is a through hole in the slit portion or a partial through hole or conductive metal. 21 is a terminal of the child board, 31 and 32 are solders. 1'is a parent board 11 '' having a conventional slit structure, and 11 'is a terminal or pattern on the front and back of 1'.

Claims (1)

[Claims] 1. A sub-board (2) is inserted into a slit (12) provided in the main board (1), and a terminal (21) of the sub-board and a corresponding pattern (11) provided on the main board (1). In the method for mounting a printed circuit board, the slits (12) of the parent board are partially through holes, the width of the slit is slightly smaller than the thickness of the child board to be inserted, and the slit portion of the parent board is A method for mounting a parent-child board, characterized in that a comb-shaped notch (17) is formed to form a projection (16), and the child board is held by the spring force of the projection when the child board is inserted into the slit.