JPS62112397A - Apparatus for correcting wiring pattern - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] The present invention provides a method for automatically identifying the front and back sides of a printed wiring board in a wiring pattern repair device that automatically adds or removes (cuts) a circuit to a printed wiring board. By adding this means, it is possible to prevent product defects due to incorrect wiring, etc.

[Industrial application field]

The present invention relates to a wiring pattern repair device used for repairing printed wiring boards.

For printed wiring boards installed in electronic computers, etc.

Even if the products are of different types, only some wiring patterns are different, and most of the circuits are often the same.

In such a case, in order to standardize the manufacturing process of printed wiring boards using automatic machines, these different types of printed wiring boards are manufactured using the same process, and then the wiring pattern modification equipment is used.

Often, the required circuits are added or removed to form the desired printed wiring board.

At this time, it is desirable that the wiring pattern repair device be configured so that product defects due to one incorrect wiring or disconnection will never occur.

[Prior Art] The work of attaching a printed wiring board to a wiring pattern repair device is generally performed manually.

Furthermore, the details of the modification of the printed wiring board are often different between the front and back sides.

Therefore, with conventional wiring pattern repair equipment.

When a worker installs a printed wiring board, do they instruct the worker to distinguish between the front and back sides?

After installing the printed wiring board, the operator inputs the distinction between the front and back sides.

[Problem that the invention seeks to solve]

In the wiring pattern repair device having the above configuration.

It was necessary for an operator to visually distinguish between the front and back sides of a printed wiring board.

For this reason, due to one worker's carelessness, the front and back sides may be mistaken, and as a result, very expensive printed wiring boards may be rejected.7Therefore, the purpose of the present invention is to:
To prevent product defects by preventing mistakes in distinguishing between the front and back sides of a printed wiring board.

c.Means for solving problems] FIG. 1 is a diagram showing the principle of the present invention.

Reference numeral 1 denotes a similarity calculation unit that calculates the similarity between the density distribution in a first predetermined area and the density distribution in a second predetermined area 9 on the printed wiring board.

Reference numeral 2 denotes a determining unit that determines whether the printed wiring board is front or back by comparing the similarity calculated by the similarity calculation unit 1 with a predetermined reference value.

[Effect]

A printed wiring board usually has a frame-like non-patterned area around it, and a pattern that is wider than other general patterns, such as a ground bus or power bus, located slightly inside the periphery. It is.

Usually, these patterns are provided only on one of the front and back surfaces, and the area on the opposite side is often left without a pattern.

Therefore, if we focus on the area on the ground pattern and the adjacent area with no pattern, we can see that there is a relatively significant difference in the concentration distribution between the two areas, whereas when this printed wiring board is turned over, In this state, there is almost no difference between the concentration distributions of the two regions corresponding to each region.

The present invention has focused on the above-mentioned situation, and is designed to distinguish between the front and back sides of a printed wiring board based on the degree of similarity between the density distributions of two regions.

〔Example〕

FIG. 2 is a block diagram showing an embodiment of the present invention, in which the reference numerals explained in FIG. A density measurement device that measures pixel by pixel and outputs it as a digital value.

Reference numeral 4 denotes a memory in which reference values used in the discriminating section 2 are stored.

Further, 11, 12, and 13 are components of the similarity calculation unit 1.

Reference numeral 11 denotes an appearance frequency counting circuit that counts the appearance frequency of each pixel of the density obtained by the density measuring device 3.

A memory 12 stores concentration distribution curves obtained by the appearance gradient counting circuit 11 for each of the first predetermined area and the second predetermined area on the printed wiring board.

13 is a concentration distribution curve obtained from the first predetermined area;
This is an arithmetic circuit that calculates the area of one overlapping portion with the concentration distribution curve obtained from the second predetermined region.

That is, the positioning of the printed wiring board is controlled by an orthogonal moving table (XY table) 9 (not shown), and the density measuring device 3 measures the density of each pixel in a first predetermined area and a second predetermined area on the printed wiring board. are measured, and the respective concentration distribution curves (see FIG. 3) obtained by the appearance frequency counting circuit 11 are stored in the memory 12.

Next, the arithmetic circuit 13 calculates the area of the overlapping part of the two concentration distribution curves stored in the memory 12 (the hatched part in FIG. 3).

Since the concentration distribution curve can generally be approximated by a normal distribution curve, the arithmetic circuit 13 can be constructed at low cost by a general-purpose arithmetic module for normal distribution curves, and calculates the mean value μ and standard deviation g of each concentration distribution curve. Required calculations can be easily performed using parameters.

Figure 3 (assuming that al is the concentration distribution curve obtained from the front surface of the printed wiring board, the concentration distribution curve as shown in the figure (+) from the back side is obtained, and the area of the double overlapped part is (
It is very small compared to al.

Therefore, by comparing the area obtained by the arithmetic circuit 13 with a reference value in the determining section 2, it is possible to easily determine whether the printed wiring board is front or back.

By using the discrimination results obtained in this way, it is possible to add or remove (cut) circuits to a printed wiring board without error, and prevent product defects! can be

〔Effect of the invention〕

As explained above, according to the present invention. It is possible to prevent product defects due to incorrect wiring or accidental disconnection in the wiring pattern repair device.

[Brief explanation of drawings]

Figure 1 shows the principle of the invention. Figure 2 is a block diagram of the embodiment; FIG. 3 is an explanatory diagram of the embodiment. In the figure. 1 is a similarity calculation unit, 2 is a discrimination unit. 3 indicates a concentration measuring device, and 4 indicates a memory.

Claims (1)

[Claims] A wiring pattern repair device that automatically adds or removes circuits on a printed wiring board based on given work data, comprising: a concentration distribution in a first predetermined area on the printed wiring board and a second a similarity calculation unit (1) that calculates the similarity with the density distribution of a predetermined region of the printed wiring board; A wiring pattern repair device characterized by comprising a discrimination section (2) for discriminating front and back sides.