JPS61209805A - Drill hole detecting method for printed circuit board - Google Patents

Abstract

PURPOSE:To quickly confirm the completion of drilling for the purpose of preventing a device from lost motion or the like and smoothly performing drilling by connecting electrodes for conduction to conductive layers for wiring of both sides of a printed circuit board and conducting a drill using it as a conductor. CONSTITUTION:Conductive layers 21 and 22 for wiring of a printed circuit board 1 are connected to electrodes 23 and 24 for conducting leading to a detecting section 25. When a drill 2 penetrates conductive layers 21 and 22 for wiring of both sides of the board, the drill becomes a conductor to detect timely the completion of drilling and performs the next work. On the other hand, even if the drill becomes incapable of drilling due to drill break or the like resulting in lost motion, the feed back is made to the circuit for driving a drill head 3 to perform the quick removal of abnormality making it possible to resume the normal drilling without delay.

Description

Detailed Description of the Invention [Summary] When through-holes are sequentially drilled in a multilayer printed circuit board by operating a drill head to interconnect printed wiring patterns on the inner layer and the front and back surfaces, the surface of the printed circuit board is Komei connected a conductive electrode connected to the detection part to the conductive layer for printed wiring on the back side, and connected the conductive layer between the conductive layers for printed wiring on the front and back sides of the printed circuit board using a drill that penetrated the printed circuit board. A method in which it is possible to quickly confirm whether or not drilling has been completed by detecting the presence or absence of the hole.

[Industrial application field]

The present invention relates to an improvement in a method for detecting perforations in printed circuit boards, which is applicable to the process of drilling for plating through-holes using a drill machine equipped with an NC in the manufacture of printed wiring boards.

In recent years, with rapid advances in electronic and semiconductor technology, printed wiring boards have become increasingly multi-layered and have high-density wiring patterns.
In the manufacturing process of these printed wiring boards, an NC drill is used at a predetermined position on the printed circuit board to form conductive through holes that connect the front and back sides of the printed circuit board, or the multilayered inner layer and outer layer printed wiring circuits. A hole is made using a machine, and a conductor is applied to the inner surface of the hole by, for example, chemical or electrical plating. after that,
The printed wiring conductive layers on the front and back surfaces of the printed circuit board are patterned into a predetermined pattern to form a printed wiring pattern.

During the process of drilling holes in printed circuit boards, the hole may break when the drill is inserted into the drill head, and in this case, the breakage cannot be detected immediately, so After the drill continued to blankly hit several planned locations on the printed circuit board,
For the first time, an alarm is displayed and maintenance is carried out to prevent such anomalies, so that such abnormal situations can be detected early and
There is a desire to eliminate blank drilling caused by broken drills.

[Conventional technology]

Conventionally, when drilling a printed circuit board using a drill machine with an NC, a method for detecting and confirming the completion of drilling in the process is as shown in FIG. A cutting powder suction section 4 is attached to the inserted drill head 3, and a powder flow detection sensor 5, for example, is arranged in the suction path of the cutting powder suction section 4.

Therefore, when the drill head 3 is operated to drill a predetermined hole in the printed circuit board 1 at the position H1 with the drill 2, the cutting dust generated at the same time is removed by the cutting dust suction unit 4.
be excluded.

At this time, the sucked cutting powder is detected by the powder distribution detection sensor 5 attached to the suction path of the cutting powder suction unit 4, and it is confirmed that drilling has been completed based on the detected amount of the cutting powder circulating, for example. be done.

This confirmation signal is fed back to the circuit 7 that numerically controls the operation of the drilling machine 7 and 3 based on the design data 6, and a signal is output to the drill head drive mechanism 8 for the next drilling machine.

[Problem that the invention seeks to solve]

However, according to such a perforation detection method, the perforation is detected by the drill 2 during the perforation process on the printed circuit board 1.
If the hole is broken, the hole at position 2 will continue cutting until the amount of cutting waste generated from the part is detected by the powder flow detection sensor 5 from the point of breakage, or the next hole from the point of breakage will be Due to the time lag until the powder was detected, the breakage could not be detected immediately, and the drill 2 in the broken state continued to drill several holes one after another at the planned positions H2, 83.
After blankly hitting ..., the alarm is displayed for the first time,
There was an inconvenience in that the operation had to be abnormally and urgently stopped.

Further, due to such inconvenience, maintenance such as replacing the drill 2, treating the printed circuit board 1, and restarting the operation of the printer cannot be done quickly.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention, as shown in the principle diagram of FIG. When sequentially drilling holes, conductive layers 21.2 for printed wiring on the front and back surfaces of the printed circuit board 1 are prepared in advance.
2, the conductive electrodes 23 and 24 connected to the detection part 25
are connected, and when the drill 2 penetrates the printed circuit board 1 by operation, Komei detects the conductive state between the printed wiring conductive layers 21 and 22 on the front and back surfaces of the printed circuit board 1 via the drill 2. This is based on a method of confirming that the drilling is completed by detecting it with the section 25.

[Effect]

That is, in such a detection method, when the drill 2 penetrates the printed circuit board l by operation, the hole between the printed wiring conductive layers 21 and 22 on the front and back surfaces of the printed circuit board 1 is detected through the drill 2. By detecting the continuity state, it becomes possible to quickly confirm whether drilling is completed, drilling is not possible due to drill breakage, etc., or dry drilling, etc. By feeding these confirmation signals back to the numerical control circuit 7, drilling can be performed. , the Kongming can immediately continue or perform abnormal treatment, and the normal Kongming after the abnormal treatment can quickly resume operation.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is an explanatory diagram showing an embodiment of the method for detecting perforations in a printed circuit board according to the present invention.

As shown in the figure, when operating the drill head 3 on the printed circuit board 1 to sequentially drill through holes for interconnecting the printed wiring patterns on the inner layer and the front and back surfaces, the printed wiring patterns on the front and back surfaces of the printed circuit board 1 are drilled in advance. conductive layer 21.2
2 is a conduction electrode 23 connected to the detection part 25.
．． Connect and place 24.

Next, when the drill 2 penetrates the printed circuit board 1 through the operation of Komei, conduction is established between the conductive layers 21 and 22 for printed wiring on the front and back surfaces of the printed circuit board through the drill 2.

By detecting this conductive state with the detection section 25, completion of the opening can be quickly confirmed. Similarly, if it is impossible for the drill 2 to drill a hole that does not penetrate the printed circuit board 1 due to a broken drill or the like, naturally there will be a non-conducting state between the printed wiring conductive layers 21 and 22 on the front and back surfaces of the printed circuit board. , this state is quickly detected by the detection unit 25.

That is, to detect the presence or absence of continuity, in other words, to determine whether or not drilling has been completed, a signal for one hole is output from the numerical control circuit 7 to the drill head drive mechanism 8 based on the design data 6. After that, the aperture can be detected in a timely manner during the completion of the operation.

Therefore, these detection signals are immediately fed back to the numerical control circuit 7, and it is of course possible to continue the process or take measures such as displaying an abnormality alarm or stopping operation. , repairs can be made quickly.

〔Effect of the invention〕

As is clear from the above explanation, according to the printed circuit board perforation detection method according to the present invention, the perforation of the printed circuit board is determined whether or not the perforation in the process is completed, It has the excellent advantage of being able to quickly detect the presence or absence of continuity between the conductive layers for printed wiring on the front and back sides of the board, and in the event of an abnormality due to a broken drill, it can be quickly repaired, and normal drilling can be performed without operation. It will be possible to restart the project at an early stage.

Therefore, the present invention is extremely advantageous in that it can be used in the process of drilling holes for plating through holes in various printed circuit boards having conductive layers for printed wiring on the front and back surfaces using an NC drill machine.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the principle of the method for detecting perforations in a printed circuit board according to the present invention, FIG. 2 is an explanatory diagram showing an embodiment of the method for detecting perforations in a printed circuit board according to the present invention, and FIG. 3 is a conventional diagram FIG. 2 is a diagram for explaining an example of a method for detecting perforations in a printed circuit board. In Figures 1 and 2, 1 is a multilayer printed circuit board, 2 is a drill, 3 is a drill head, 6 is data, 7 is a numerical control circuit, 8 is a drill head drive mechanism, and 21 and 22 are for printed wiring. conductive layer, 2
Reference numerals 3 and 24 indicate conduction electrodes, and 25 indicates a detection portion, respectively. Introduction octopus/I drunkenness 4th figure 1 snoring 71. @:flJ t-de-1 and Figure 2 Explanatory diagram of section mismatching Figure 3

Claims (1)

[Claims] By operating the drill head (3) on the printed circuit board (1),
When sequentially drilling through holes for interconnecting printed wiring patterns on the inner layer and the front and back surfaces, conductive layers for printed wiring (21) on the front and back surfaces of the printed circuit board (1),
Connect the conductive electrodes (23) and (24) connected to the hole detection section (25) in advance to (22), and connect the printed circuit board (1) through the drill (2) by drilling the hole. Conductive layers for printed wiring on the front and back surfaces of the board (1) (
21) A method for detecting perforation of a printed circuit board, characterized in that completion of perforation is detected by a conduction state between (21) and (22).