JPH0214210Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is a multilayer board in which an electric circuit is formed using conductive layers such as copper foil on the front and back surfaces of multiple boards and between the boards. The present invention relates to a repair terminal for a multilayer board that is used to repair a short circuit when the conductive layers between the layers are short-circuited.

[Conventional technology]

Conventionally, through holes in a multilayer board are configured as shown in FIG.

In FIG. 6, 1a, 1b, and 1c are insulating substrates made of epoxy resin or the like, and conductive circuits 2a such as copper foil are provided on the surfaces of the substrates, and conductive circuits 2b and 2c are also provided between the substrates 1a and 1b, and between 1b and 1c. However, a conductive circuit 2d is also formed on the back surface, and the substrates 1a, 1b, 1c are stacked and bonded to form a multilayer substrate.

A hole 3 is formed in this multilayer board, and a conductive layer 4 such as copper foil provided in the hole 3 connects the conductive circuit 2a on the front surface and the conductive circuit 2d on the back surface, and the through hole It is becoming.

In the through holes of such multilayer boards,
The conductive layer 4 in the hole 3 and one or both of the conductive circuits 2b, 2c formed between the substrates 1a, 1b, 1c come into contact as shown in FIG. 7, resulting in a short circuit,
You may end up with a defective multilayer board.

A conventional repair method for such defective products will be explained with reference to FIGS. 8 to 12.

First, use a drill with a diameter that allows you to scrape off the conductive layer 4 of this defective through hole.
A hole 3 is made and the conductive layer 4 is scraped off to form the state shown in FIG.

The cut hole 3 is filled with an insulating adhesive 5 as shown in FIG. 9, and the adhesive is waited for to solidify.

After the adhesive 5 hardens, a hole 6 is drilled in the center of the adhesive 5 using a drill with a smaller diameter than the drill used previously, as shown in FIG.

Insert the eyelet 7 into this hole 6 and swage it as shown in Fig. 11.
The adhesive 5 insulates the two.

Then, as shown in Figure 12, the head 7 of the eyelet 7
a and the caulking portion 7b are respectively connected to the conductive circuit 2.
Solder a and 2b with solder 13 to form conductive circuit 2.
Connect a and 2d to complete the repair.

[Problems to be solved by the invention] Repairing the short circuit in the through-hole of a multilayer board as described above not only requires two hole-drilling steps and multiple steps of filling the adhesive 5; This has the disadvantage that the internal conductive circuit is likely to be exposed due to misalignment during the second hole drilling, and a long waiting time is required to wait for the adhesive 5 to harden, making the repair extremely inefficient. .

[Purpose of invention]

This invention is a repair terminal that eliminates the shortcomings of conventional through-hole short-circuit repairs in multilayer boards.The repair can be completed in three steps: drilling, caulking, and soldering, making the repair extremely efficient. Furthermore, the purpose is to eliminate the difficulty in each process so that anyone can easily perform repairs.

[Summary of the idea]

In order to achieve the above-mentioned object, the present invention attaches an insulating tube to the cylindrical part under the head of a conductive cylindrical body such as an eyelet whose head is expanded, except for the lower end for caulking. This is a repair terminal for a multilayer board in which an insulating layer is formed by fitting or applying an insulating paint.

[Example of idea]

An embodiment of a repair terminal for a multilayer board according to the present invention is shown in FIG.

The base 11 of this repair terminal is formed by expanding the head 11a of a conductive cylindrical body made of copper or the like, and the lower end 11b is formed in the shape of an eyelet, which is expanded by caulking after being inserted into a required hole. ing.

An insulating tube 12 is inserted into a cylindrical portion 11c between a head portion 11a and a lower end portion 11b of this base body 11.

A method of repairing a short circuit in a through hole of a multilayer board using the repair terminal A will be explained with reference to FIGS. 2 to 4.

As shown in FIG. 2, in order to scrape off the conductive layer 4 in the hole 3 which is short-circuited with the conductive circuits 2b, 2c between the substrates 1a, 1b, 1c, the diameter of the hole 3 and A hole 3 is drilled with a drill of the same or slightly larger diameter, and the conductive layer 4 is scraped off.

This process is the same as that shown in FIG. 8 of the conventional repair method.

Then, as shown in FIG.
Crimp and expand b.

At this time, the conductive base 11 is connected to the insulating tube 12.
Since it is insulated from the conductive circuits 2b and 2c, no short circuit will occur between them.

Then, as shown in FIG. 4, the head 11 of the base 11 is
a and the conductive circuit 2a and the lower end portion 11b and the conductive circuit 1
1d with solder 13 to connect them and complete the repair.

FIG. 5 shows another embodiment of the repair terminal A, with the base 1
1, a lug 11d for soldering a lead wire is protruded from the head 11a, and a cylindrical portion 11c
An insulating coating 14 is applied to the insulating layer to form an insulating layer.

The repair method using this repair terminal A may be performed in the same manner as the repair method of the previous embodiment.

[Effect of idea]

Repairing a short circuit in a through hole in a multilayer board using the repair terminal of the present invention requires only one drilling operation to scrape off the conductive layer inside the through hole, as described above, which can shorten the process more quickly than the conventional two-step process. It does not involve difficult work such as drilling a hole in the center of the filled adhesive, and therefore can be easily performed even by an unskilled person.

The pre-installed insulating layer of the repair terminal insulates the conductive circuit between the multilayer boards, eliminating the need for conventional adhesive filling and wasted time waiting for the adhesive to harden. can.

Therefore, the number of drilling steps is reduced, the repair work can be made more efficient, and the repair cost can be reduced.

In addition, since a defective multilayer board due to a short circuit in a through hole can be repaired, it has the advantage that what was conventionally discarded can be used as is.

[Brief explanation of the drawing]

Figure 1 is a perspective view of an embodiment of the present invention, Figures 2~
Figure 4 is a sectional view showing the repair process using this.
FIG. 5 is a sectional view of another embodiment, FIG. 6 is a sectional view of a multilayer board, FIG. 7 is a sectional view showing a short circuit in the through hole, and FIGS. 8 to 12 show a conventional repair process. FIG. A... Repair terminal, 11... Base, 11a... Head, 11b... Lower end, 11c... Cylindrical part, 11
d...Lug, 12...Insulating tube, 13...Solder, 14...Insulating paint.

Claims (1)

[Scope of utility model registration request] A cylindrical part is formed at one end of the conductive cylindrical body to extend from the head and is inserted into a through hole formed in the multilayer board with a margin, and the cylindrical part is The length is longer than the thickness of the multilayer substrate, and an insulating layer having a length substantially equal to the thickness of the multilayer substrate is formed on the outer peripheral surface of the cylindrical portion below the head. Repair terminal for multilayer board.