JPH09331144A - Printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily put the lead of an electric component into an interface input/output terminal insertion through-hole so as to make the electric component get least out of a mounting position by a method wherein the opening of the insertion through-hole is formed like a funnel, and the through-hole continuously connected to the funnel-like opening is reduced to an irreducible minimum in diameter. SOLUTION: The one side of a PKG main board 1 denotes a component mounting surface 1a, and the other side denotes a soldering surface 1b. A through-hole 2 is provided in the PKG main board 1 through a countersinking process. A part of the through-hole 2 as long as α from the soldering surface 1b of the main board 1 has a cylindrical inner wall 2b of diameter X, and the residual part of the through-hole 2 is so formed as to spread gradually at an angle of θ deg. till it reaches to the component mounting surface 1a. Therefore, the lead of an electric part is inserted into the through-hole 2 through the opening 2a which spreads wide facing outwards without substantially enlarging the diameter of the through-hole 2, so that it is easily guided into the through-hole 2. The leads of an electric component are still easily aligned with the through-hole even if the leads are increased in number.

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 (abbreviated as PKG) constituting a communication device, a computer or the like.
The structure of through holes and lands of PKG.

[0002]

2. Description of the Related Art A device such as a communication device or a computer can be said to be an assembly of a plurality of PKGs on which electric parts are mounted. In recent years, these devices are required to be downsized and to have multiple functions, so that mounting of electric parts on the PKG, which is the center of the devices, is further increased in density. Under these circumstances, the electric components themselves to be mounted have been made smaller and have higher performance. Further, these electric components are often developed independently for each device, and there is a marked tendency that multiple functions are integrated in one component. Therefore, the number of interface input / output terminals is also increasing. Then, these electric components are mounted on the PKG, and a circuit is formed by connecting to other electric components via the PKG.

3 and 4 are a perspective view and a sectional view for explaining the above-mentioned prior art in detail. Of these, FIG. 3 shows an example of an electrical component, and the main body 10 is provided with an interface input / output terminal (abbreviated as a lead) 11 for interfacing with other electrical components. The lead 11 is put into a through hole (component hole) described later, which is formed in the PKG, and is fixed by soldering. The through hole used for this component hole is made conductive by electroless copper plating, and is connected to other electric components by the pattern line connected to the through hole.

FIG. 4 shows a partial cross-section of the PKG. One surface of the substrate body 12 is a component mounting surface 12a and the other surface is a solder surface 12b. A through hole 13 having a cylindrical inner wall is formed in the substrate body 12. The hole diameter x of the through hole 13 is appropriately formed according to the outer shape of the lead 11 of each electric component.

[0005]

By the way, the electric parts mounted on the PKG are originally developed according to the use of the device, and the size, the number of leads, the distance between the leads, etc. are as follows.
Often different from other parts. On the other hand, in the case of mounting an electrical component having many leads 11, each of the leads 11 has a through hole 13 formed in the cylindrical inner wall.
Must fit in place within. However, as the number of leads 11 of electrical parts increases, the through hole 1
There was a problem that the dimensional accuracy with the predetermined position of No. 3 could not be maintained and the positions were not aligned, it took time to insert the lead 11, and the workability was poor.

As a method for solving this problem, a method of widening the diameter of the through hole 13 can be considered.
The distance between and will increase accordingly. Then, the lead 11 is in a so-called idle state in the through hole 13, and the mounting position of the electric component is displaced. further,
Electric parts may come into contact with peripheral parts, or the same PKG
However, there was a problem that the appearance was extremely different and uniform quality could not be maintained.

In order to solve the above-mentioned problems, the present invention provides a printed circuit board which can easily insert the lead 11 of the electric component into the through hole 13 and can minimize the displacement of the mounting position of the electric component. This is the purpose.

[0008]

In order to achieve the above object, the present invention forms a through hole for inserting and fixing an interface input / output terminal of an electric component from one surface to the other surface of a substrate body, and this through hole is formed. In the printed circuit board in which the land was formed near the hole, the interface input / output terminal insertion port was opened in a funnel shape, and the hole continuous to the funnel shaped opening was formed as a through hole with a minimum necessary diameter.

[0009]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a partial cross-sectional view of the PKG. One surface is a component mounting surface 1a and the other surface is a solder surface 1b. And PKG body 1
A through hole 2 which is machined with a countersink is formed in the. In forming the through-hole 2 as shown in the figure, the PKG body thickness α from the solder surface 1b is the cylindrical inner wall 2b with a diameter x, but it gradually opens to θ ° from there to the component mounting surface 1a. Formed (opened like a funnel)
doing.

By forming the through hole 2 as described above, the opening 2 in which the lead of the electric component is largely opened to the outside without substantially increasing the hole diameter of the through hole 2.
Since it is inserted from a, it can be easily introduced into the inside. Further, even if the number of leads of the electric component increases, the alignment with the through hole 2 does not become difficult. Further, once inserted, the lead is regulated by the thickness α of the PKG body from the solder surface 1b, and the mounting position deviation of the electric component can be minimized. That is, the cylindrical inner wall 2 having the diameter x
It is possible to suppress the mounting position deviation similar to the through hole 2 formed by only b.

FIG. 2 is a plan view of a through hole 2 which has been machined with countersinks (counterbores). As shown in the figure, through holes 2 are formed in two places with a pattern line 3 for connecting with other electric parts interposed therebetween.
The land 4 on the component mounting surface 1a side is formed to be vertically long so as to surround the. Here, the land 4 on the component mounting surface 1a side will be described. By forming the through hole 2 as a countersunk through hole, the opening on the component mounting surface 1a side becomes large, and the land 4 originally looks like a broken line display 4a. Will end up. Then, since the pattern line 3 cannot be interposed between the through holes 2, the land 4 is not connected to the pattern line 3.
In order to avoid the above, it is formed in a longitudinal direction in the plane direction so that the drawing efficiency of the pattern line 3 is not deteriorated.

[0012]

As described above, according to the present invention, the interface input / output terminal insertion port is opened in a funnel shape, and the hole continuous to the funnel-shaped opening forms a through hole with a minimum necessary diameter. Since the lead of the electric component is inserted from a large opening to the outside without substantially increasing the hole diameter of the hole, it can be easily introduced into the inside. Further, even if the number of leads of the electric component increases, the alignment with the through hole does not become difficult, and the workability does not deteriorate. Further, once inserted, the lead is regulated by the cylindrical inner wall, and the mounting position deviation of the electric component can be minimized. Further, it is possible to maintain uniform PKG quality by suppressing the mounting position deviation of the electrical components.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a PKG.

FIG. 2 is a plan view of a through hole that has been machined with a plate fir.

FIG. 3 is a perspective view showing an example of an electric component.

FIG. 4 is a partial cross-sectional view of a PKG according to a conventional example.

[Explanation of symbols]

 1 PKG body 1a Component mounting surface 1b Solder surface 2 Through hole 2a Opening 2b Cylindrical inner wall

Claims (1)

[Claims] 1. A printed circuit board in which a through hole for inserting and fixing an interface input / output terminal of an electric component is formed from one surface of the substrate body to the other surface, and a land is formed in the vicinity of the through hole. The printed circuit board is characterized in that the input / output terminal insertion port is opened in a funnel shape, and a through hole is formed in the hole continuous to the funnel-shaped opening with a minimum necessary diameter.