JPH0521923A - Printed wiring board - Google Patents

Abstract

PURPOSE:To detect the positional displacement of silk printing electrically by whether or not a probe is brought into contact with a copper foil for grounding when a wiring is inspected by forming a dotted or ring-shaped silk printed section onto the copper foil for grounding. CONSTITUTION:A dotted silk printed section 2a is printed onto the grounding copper foil 4 of a printed wiring board 1, Pads 3 for mounting electric parts are formed to the printed wiring board 1, silk printed sections 2 are also formed around the pads 3, and a position, where soldering is unnecessitated, is covered with a solder resist 5. A wiring inspection jig probe can be brought into contact with the silk printed section 2, Accordingly, the wiring inspection jig probe is brought into contact with the grounding copper foil 14 and the positional displacement of silk printing electrically when the silk printed section 2 is positional-displaced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a printed wiring board.

[0002]

2. Description of the Related Art In recent years, the surface mounting of electric parts has progressed, and as for printed wiring boards for mounting these, the number of printed wiring boards having pads for mounting electric parts is increasing. Along with this, the density of the mounted components has been increased, and in the silk screen printing showing the pads for mounting the electric components, high-precision products having a narrow gap between the pads and the silk are required.

For this reason, there is a problem that silk is applied to the pad due to the displacement of silk printing. Conventionally, in this type of printed wiring board, a defective product is detected by visually inspecting a displacement of silk printing from relative positions of a land and a pad and a silk printing symbol surrounding them.

[0004]

In the above-mentioned conventional printed wiring board, the inspection of the positional deviation of the silk printing is performed visually by the land and the pad and the silk printing symbols surrounding them, which is considerably large. There is a problem that it requires man-hours and it is difficult to cope with high density and high accuracy.

The object of the present invention is to solve these problems,
Another object of the present invention is to provide a printed wiring board to which a probe can be contacted so that it can be electrically detected.

[0006]

SUMMARY OF THE INVENTION The structure of the present invention is a printed wiring board having pads for mounting electric parts, and has a dot shape or a ring so that a wiring inspection jig probe can be brought into contact with a grounding copper foil. It is characterized in that it has a silk-printed part of a shape.

[0007]

FIG. 1 is a partial plan view of the first embodiment of the present invention,
FIG. 2 is a vertical sectional view taken along the line AA '. In the printed wiring board 1 of the present embodiment, the dot-shaped silk printing portion 2a is printed on the grounding copper foil 4. This printed wiring board 1
Is provided with a pad 3 for mounting an electric component, a silk printing portion 2 is also provided around the pad 3, and a portion not requiring soldering is covered with a solder resist 5. The hole 6 used for mounting is also shown.

In this embodiment, as shown in FIG. 3, the wiring inspection jig probe 7 can contact the silk printing portion 2.

With such a structure, when the silk printing portion 2 is displaced, as shown in FIG. 4, the wiring inspection jig probe 7 comes into contact with the grounding copper foil 4 to electrically silken it. It is possible to detect misalignment of printing.

FIG. 5 is a partial plan view of a second embodiment of the present invention, and FIG. 6 is a vertical sectional view taken along the line BB '. In the printed wiring board 1 of this embodiment, a ring-shaped silk printing portion 2b is provided on the grounding copper foil 4.

In this embodiment, as shown in FIG. 7, the wiring inspection jig probe 7 is brought into contact with the grounding copper foil 4. As a result, when the silk printing part 2b is displaced, the wiring inspection jig probe 7 cannot contact the grounding copper foil 4, as shown in FIG. Can be detected.

[0012]

As described above, according to the present invention, by providing a dot-shaped or ring-shaped silk-printed portion on the grounding copper foil, whether or not the probe contacts the grounding copper foil during the wiring inspection. Thus, there is an effect that the positional deviation of silk printing can be electrically detected.

[Brief description of drawings]

FIG. 1 is a partial plan view of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA ′ of FIG.

FIG. 3 is a cross-sectional view at the time of probe contact in the normal state of FIG.

FIG. 4 is a cross-sectional view when the silk position in FIG. 1 is displaced.

FIG. 5 is a partial plan view of the second embodiment of the present invention.

6 is a sectional view taken along line BB ′ of FIG.

FIG. 7 is a cross-sectional view when the probe is in contact with the normal state of FIG.

FIG. 8 is a cross-sectional view when the silk position in FIG. 6 is displaced.

[Explanation of symbols]

 1 Printed wiring board 2, 2a, 2b Silk printing part 3 Pad 4 Copper foil for grounding 5 Solder register 6 Hole part 7 Wiring inspection jig probe

Claims (1)

Claim: What is claimed is: 1. In a printed wiring board having a pad for mounting an electric component, dot-shaped or ring-shaped silk printing that allows a wiring inspection jig probe to come into contact with a grounding copper foil. A printed wiring board having a portion.