JPH02275690A - Printed circuit board - Google Patents

Abstract

PURPOSE:To eliminate works for inspecting a sewing line and removing metal and to associate in a divided state by adhering metal of through hole plating of the inner wall of sewing lines to only one of divided printed circuit boards so as not to be easily dropped. CONSTITUTION:Solder (d) is forcibly filled in sewing lines (b) in case of soldering after an electronic component is placed, and the area of a conductor land c' of the lines (b) is deviated in a predetermined direction, metal c' of through hole plating in the lines (b) is adhered to the stronger side of the land c' in case of folding. Thus, the metal (c) of through hole plating in case of folding the lines (b) is adhered to a printed circuit board associated in an electronic device, and so associated in the device that the metal is not dropped by an impact, a vibration after associating. Thus, works of inspecting the sewing lines and removing the metal can be eliminated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to printed wiring boards.

[Conventional technology]

In a printed wiring board in which through-hole plated metal is attached to the inner wall of the perforation, after electronic components are mounted, when the printed wiring board is divided into multiple parts by folding the perforation, the metal is divided. The metals adhere randomly to both sides of the wiring board, and if the printed wiring board is assembled into an electronic device in this state, the metals will fall off due to external vibrations or shocks and damage the functions of the electronic device, so the metals should be removed after dividing. I needed to.

[Problem to be solved by the invention]

The present invention solves the above-mentioned problems by attaching the through-hole plating metal on the inner wall of the perforation to only one of the divided printed wiring boards and preventing it from falling off easily. It is something to do.

[Means to solve the problem]

The printed wiring board of the present invention forcibly fills the perforations with solder during soldering after electronic components are mounted, and by biasing the conductor land area of the perforations in a certain direction, The feature is that when folded, the through-hole plated metal inside the sewing machine mouth is attached to the stronger side of the conductor land along with the solder.

[For production]

According to the present invention, through-hole plating metal when folding the perforation portion adheres to a printed wiring board incorporated into an electronic device.
To eliminate the need for inspecting perforations of a printed wiring board to be incorporated into an electronic device and removing the metal to prevent the metal from falling due to impact or vibration after installation and damaging the functions of the electronic device.

〔Example〕

Figures 1 to 3 show the state of perforations in conventional printed wiring boards. Figure 1 is an external view of the perforations, Figure 2 is a cross-sectional view (A-A') of Figure 1, and Figure 3 is a cross-sectional view of the perforations. A state diagram showing a printed wiring board divided at perforations is shown.

As shown in FIG. 2, conventional printed wiring boards include those in which the perforations are filled with solder when immersed in a solder bath and those in which solder is not filled.

Furthermore, after the printed wiring board is folded and divided at the perforations, as shown in FIG. 3, the through-hole plated metal C does not know which printed wiring board it will adhere to, and it tends to fall off due to impact or vibration.

4 to 8 show the state of perforations in the printed wiring board of the present invention. FIG. 4 is an external view of the perforation area. FIG. FIG. 7 is a sectional view taken along the line (B-B') in FIG. 4, and FIG. 8 is a sectional view taken along the line (CC') in FIG. 4.

As shown in FIG. 5, the printed wiring board of the present invention has a very small amount of conductive land C/
(or landless), a large conductor land is provided on the other side (temporarily referred to as sub printed wiring board 2), and the conductor land side, which has a very small amount of solder resist, is sufficiently spaced from the conductor land so that it does not touch the land, and a large conductor land is provided. On the conductor land side, leave a large gap from the perforation so that the solder can be applied over a wide area.

By applying this to both sides of the printed wiring board, all the perforations are filled with solder as shown in Figure 6 by immersion in a solder bath (soldering) after electronic components are mounted, and solder is filled in as shown in Figure 7. More solder adheres to the larger area of the conductor land.

If you fold the perforations and divide the printed wiring board in this state,
Due to the strong adhesion between the large conductor land and the solder-reinforced sub-printed wiring board 2 side, the through-hole plating metal on the main printed wiring board l side, which has poor adhesion, is integrated with solder and all of the sub-printing Adheres to wiring boards. (Fig. 8) [Effects of the Invention] The printed wiring board of the present invention ensures that when the printed wiring board is divided by folding at the perforation, the through-hole plating metal on the inner wall of the perforation is always attached in a fixed direction, and Since it does not fall easily even when external shocks or vibrations are applied, inspection of the perforations after division and the work of removing the metal can be eliminated, and it can be incorporated into electronic equipment in its divided state.

[Brief explanation of drawings]

1 to 3 show the perforations of a conventional printed wiring board, and FIGS. 4 to 8 show the perforations of the printed wiring board of the present invention. Figure 1 is an external view of the perforations. FIG. 2 is a sectional view (A-A') of FIG. Figure 3 is a diagram showing a printed wiring board divided at perforations. Figure 4 is an external view of the perforation. Figure 5 is an enlarged view of the appearance of the sewing machine mouth. FIG. 6 is a sectional view (BB') of FIG. 4. FIG. 7 is a sectional view (CC') of FIG. 4. FIG. 8 is a diagram showing a state in which the printed wiring board is divided at perforations. a ・ ・ O b 1 Controversy C1111・ aIld ・ Pot ・ e ・ ・ ・ ・Base material / perforation line metal for through-hole plating / conductor land / solder φ solder resist or more Applicant Seiko Epson Corporation Agent Patent attorney Suzuki Kisanbe (and 1 other person) Figure 2 Figure 3

Claims (1)

[Claims] In a printed wiring board that has perforations for dividing after electronic components are mounted and is completed with through-hole plated metal remaining on the inner wall of the perforation, the perforation Leave a conductor land at the perforation, reduce the area of one conductor land of the printed wiring board connected at the perforation, and increase the area of the other conductor land, leave the solder resist sufficiently away from the perforation, and remove the conductor land. By further increasing the escape of solder resist from the perforations of a printed wiring board with a large area, when the printed wiring board is immersed in a solder bath, all the perforations are sufficiently filled with solder and the conductive lands are Now enough solder can be placed on the land with a large area, so that when the printed wiring board is folded and divided at the perforation, the through-hole plated metal on the inner wall of the perforation will only adhere to one side of the divided printed wiring board. , and a printed wiring board characterized in that the metal does not easily fall off.