JPS6320646B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a printed board for detecting drill breakage during drilling of a printed board.

Prior Art and Problems Conventionally, multilayer printed boards have been used in electronic devices such as communication devices and electronic computing devices in order to rationalize wiring and rationalize mounting of components. This multilayer printed board is provided with through holes that are plated on the inner surface of the holes that penetrate the printed board to connect conductors between the layers. In recent multilayer printed boards, the number of through holes has increased as the packaging density of electronic devices has become more sophisticated, and one printed board now has thousands to tens of thousands of through holes.

Prior Art and Problems A high-speed numerically controlled drilling machine is usually used to prepare the through holes. On the other hand, the diameter of the pilot hole of the through hole is as narrow as 0.3 to 0.5 mm. For this reason, when the number of laminated layers of a multilayer printed board increases and the overall thickness increases, drill breakage becomes more likely to occur during drilling. Although it is possible to salvage the printed circuit board that is bent by the drill in some way, it takes a lot of effort and time to find the broken drill because there are many holes after all the holes have been machined. The workability is poor. For this reason, a method of optically monitoring the discharge state of chips is used as a means to detect drill breakage immediately after it occurs.
This method has the disadvantage that reliable detection is difficult because the chips adhere to the drill and rotate or scatter.

OBJECTS OF THE INVENTION In view of the above-mentioned conventional drawbacks, it is an object of the present invention to provide a printed board for detecting drill breakage, which can reliably detect drill breakage immediately after the breakage.

Structure of the Invention According to the present invention, when processing a through-hole in a printed circuit board to be processed,
A printed board for detecting drill breakage that is overlapped with the printed board to be processed and simultaneously processed to detect drill breakage that occurs at the same time, and which has continuous holes on at least one side in accordance with the order of drilling, and is always cut by a drill. This is accomplished by providing a printed board for detecting drill breakage, which is characterized by being provided with a conductive pattern having a width of

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

FIG. 1 is a diagram for explaining a first embodiment of a printed board for detecting drill breakage according to the present invention,
In the figure, 1 indicates a printed board for detecting drill breakage, 2 indicates a planned position for preparing a through-hole, and 3 indicates a pattern.

The printed board for detecting drill breakage in this embodiment is a single-sided printed board different from the printed board to be processed in the order of drilling the through holes in the printed board to be processed (arrow A).
A continuous single-stroke conductive pattern 3 is provided according to the method shown in FIG. Note that this pattern 3 must have a width that can be cut by a drill at the position 2 where the through-hole is to be drilled, and may be thicker in other parts as in part B.
In addition, pattern 3 does not necessarily need to connect the through-hole prepared hole processing positions at the shortest distance, and may be detoured as in section C if necessary.

This embodiment thus configured is used in the following manner. FIG. 2 is a diagram showing the hole machining state, and in the figure, 1 indicates a printed board for detecting drill breakage, 4 indicates a printed board to be machined, and 5 indicates a drill. In this case, the printed board to be processed 4
must have its entire surface 4a covered with copper foil, and this copper foil and drill breakage detection printed board 1
A detector 6 capable of checking continuity is connected between the pattern 3 and the pattern 3. Note that the location where the detector 6 of pattern 3 is connected is at the end of the drilling order. If the hole is drilled in this way, as shown in Figure 3, the distance between the drill breakage detection printed board pattern and the copper foil of the workpiece printed board becomes a shot while the drill is descending. When the morning ends and the drill rises, it opens and information such as part a can be obtained. Further, if the drill breaks during drilling, even after the drill is lifted up, the pattern of the printed board for detecting drill breakage and the printed board to be processed will continue to be shot by the broken drill, resulting in information such as part b. If the next hole drilling is normal, the pattern of the printed board for detecting drill breakage will be cut, so the shot part will be open to the copper foil of the printed board to be processed, as shown in part c, and will prevent subsequent drill breaks again. can be detected.

FIG. 4 is a diagram for explaining another embodiment of the printed board for detecting drill breakage according to the present invention, and the embodiment shown in FIG.
The embodiment shown in figure b has a single stroke pattern 3 on one side of the double-sided printed board, and the copper foil 8 is left on the entire surface of the other side, and the embodiment shown in figure c has a single stroke pattern 3 on both sides. Patterns 3 and 3' are provided. The pattern 7 or the copper foil 8 in the embodiment shown in a and b has the same effect as the copper foil on one side 4a of the printed board to be processed explained in FIG. 2, and the pattern 7 or the copper foil 8 in the embodiment shown in FIG. In this case, single-stroke patterns 3 and 3' are continuously provided over two layers in such a case that the lines intersect with each other. In this embodiment configured in this way, while the drill is being lowered during drilling, the drill moves pattern 3 and pattern 7 at a, and at b.
In c, pattern 3 and copper foil 8 are pattern 3.
Alternatively, 3' and the copper foil of the printed board to be processed become in a shortened state, and after the drill is raised, they are in an open state, but if the drill breaks, they remain in a shortened state. Therefore, by detecting this shot condition, drill breakage can be detected. Further, after the drill breaks, the pattern 3 or 3' is cut and opened by drilling the next hole, so there is no problem in detecting the drill break in the future.

Effects of the Invention As explained in detail above, the printed board for detecting drill breakage of the present invention is capable of detecting drill breakage for each hole by providing a single stroke pattern on at least one side in accordance with the order of hole machining. The effect is huge.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a printed board for detecting drill breakage according to the present invention, and FIGS. 2 and 3 are for explaining a method for drilling holes in a printed board using the printed board for detecting drill breakage of the present invention. FIG. 4 is a diagram for explaining another embodiment of the printed board for detecting drill breakage according to the present invention. In the drawings, reference numeral 1 indicates a printed board for detecting drill breakage, 2 indicates a planned position for drilling a through-hole, 3 indicates a single-stroke pattern, 4 indicates a printed board to be processed, 5 indicates a drill, and 6 indicates a detector.

Claims (1)

[Claims] 1. A drill breakage detection printed board for detecting drill breakage that occurs when machining a through-hole on a printed board to be processed at the same time by overlapping the printed board to be processed, which includes at least 1. A printed board for detecting drill breakage, characterized in that a conductive pattern is provided on one side in a continuous manner according to the order of hole processing and has a width that is always cut by a drill.