JP2001013189A - Control method for circuit board inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct a 'kink' present in a table moving means to accurately position an X-Y table. SOLUTION: In advance of inspection of a circuit board D, a surface of an X-Y table 4 is sectionalized into plural blocks, while the X-Y table 4 is moved to a position of a board inspection jig 6 on the basis of preset position designation data in design, and the respective blocks are marked with strike marks by a probe pin. Then, an image of the strike marks of the respective blocks is picked up by a camera 11, and strike mark position data are acquired by an image processing means. Difference between the strike mark position data and the position designation data is calculated and maintained as offset data. When subsequently inspecting the circuit board D, table moving means 2, 3 are controlled with the offset data added to the position designation data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a circuit board inspection apparatus, and more particularly, to a method for controlling the movement of an XY table for transporting a circuit board to be inspected to a board inspection jig. .

[0002]

2. Description of the Related Art Circuit board inspection apparatuses are roughly classified into a pin boat type and an XY type. According to the pin board method, since multiple points can be inspected at a time, it is suitable when the number of inspection boards is large. On the other hand, it is necessary to produce an expensive pin board every time the type of substrate changes.

On the other hand, in the XY method, an inspection is performed by moving a few probe pins to an inspection location based on pre-programmed position data, so that an expensive pin board is not required. This is suitable when the number of test boards is relatively small. However, the time required for inspecting one substrate becomes longer.

As described above, both types have advantages and disadvantages. Therefore, as an eclectic scheme, there is an XY table type. This is particularly suitable for inspection of a multi-circuit board, and its basic configuration will be described with reference to the schematic diagram of FIG.

That is, this circuit board inspection apparatus 1
The apparatus includes an X-axis moving unit 2 arranged in the axial direction and a Y-axis moving unit 3 arranged in the Y-axis direction. X axis moving means 2
The Y-axis moving means 3 comprises a feed screw shaft, a linear guide rail, or the like, and its feed is controlled by, for example, servo motors 2a and 3a as driving means.

In this example, the Y-axis moving means 3 is moved in the X-axis direction by the X-axis moving means 2,
A table 4 on which the circuit board D to be inspected is mounted is attached to the Y-axis moving means 3. Therefore, CPU (central processin) as control means
g unit) 5 controls the driving of the servomotors 2a and 3a based on the predetermined position data, so that the table 4 is moved in the XY directions.

Assuming that the moving range of the table 4 is within the chain line frame in FIG. 4, the board inspection jig 6 is located at a predetermined position within the range.
Is provided. Although not shown in detail in FIG. 4, the board inspection jig 6 includes a pin board on which a plurality of probe pins are implanted. In the case where the circuit board D to be inspected is a multiple circuit board having a plurality of circuit board formation areas, the pin board has either a size corresponding to one circuit board formation area or a size extending over a plurality of circuit board formation areas. You.

According to the circuit board inspecting apparatus 1, the circuit board to be inspected (multiple circuit board) D is placed on the table 4 and the X-axis moving means 2 and Y It is carried to a position below the substrate inspection jig 6 by the axis moving means 3. Then, a pin board type inspection is performed by the substrate inspection jig 6.

[0009]

By the way, in recent years, circuit patterns have been increasingly refined, and accordingly, the table 4 is also required to have a high positional accuracy in μ units.

However, even if the X-axis moving means 2 and the Y-axis moving means 3 are composed of feed screw shafts or linear guide rails, the shafts and rails are slightly skewed.
Exists. In other words, as shown in the enlarged view of FIG. 5, the design is designed to be ideally straight, as shown by the dashed line in the drawing, but in the actual machining process, the "deformation" as shown by the solid line in the drawing occurs. Would.

The size of the "skew" has no regularity and differs depending on the position. Therefore, when looking at, for example, the circuit board forming regions D1 and D8 in a diagonal relationship on the multi-surface substrate D, when one of the circuit board forming regions D1 is positioned below the board inspection jig 6, the “skew” occurs. Size (ΔX1, ΔY
1) and the size of the “skew” (ΔX8, ΔY) when the circuit board formation region D8 is positioned below the board inspection jig 6.
8) is different, so that it is not easy to correct by the CPU 5.

[0012]

The present invention has been made to solve such a problem.
It is possible to correct the “skew” existing in the Y moving means,
An object of the present invention is to provide a control method of a circuit board inspection apparatus capable of performing high-accuracy positioning of a Y table.

In order to achieve the above object, the present invention provides a table on which a circuit board to be inspected is mounted, a table moving means for moving the table in the X-axis direction and the Y-axis direction,
A board inspection jig provided at a predetermined position within a moving range of the table and having a probe pin selectively contacting the circuit board to be inspected, and controlling operations of the table moving means and the board inspection jig; Control means for performing
A control method of a circuit board inspection apparatus for controlling a table moving amount when the table is moved to a position of the substrate inspection jig, comprising: a camera for imaging the table surface; The upper part is divided into a plurality of blocks, and the table is moved to the position of the board inspection jig based on the design position designation data set in advance in the control means, and each of the tables is moved by the probe pins. After making a dent for each block, the camera captures the dent of each block, obtains the dent position data by the image processing means, and obtains the dent position data and the position by the control means. After calculating the difference with the designated data, the control means controls the table moving means by adding the difference data to the position designation data. It is characterized in.

That is, prior to the inspection of the circuit board, correction data due to the “Y” of the XY moving means is obtained for each block of the table, and when inspecting the circuit board, the position designation data is corrected by the correction data. According to this, each block can be accurately positioned with respect to the board inspection jig.

When the circuit board to be inspected is a multiple circuit board having a plurality of circuit board formation areas, it is preferable to divide the table surface into a plurality of blocks in accordance with each circuit board formation area.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to an embodiment shown in the drawings. FIG. 1 is a schematic diagram of this embodiment, and the same reference numerals as those in the conventional example of FIG. 4 described above denote the same parts.

In this circuit board inspection apparatus 10, X
An axis moving means 2 and a Y axis moving means 3 are provided. Each of the moving means 2 and 3 may be, for example, a feed screw shaft or a linear guide rail driven by a servo motor 2a, 3a or the like.

A table (XY table) 4 on which the circuit board D to be inspected is mounted is attached to the Y-axis moving means 3 side. In this embodiment, the Y-axis moving means 3 is movable in the X-axis direction by the X-axis moving means 2, but the table 4 is provided on the X-axis moving means 2 side, and the X-axis moving means 2 is moved to the Y-axis direction. The moving means 3 may be movable in the Y-axis direction.

In any case, the board inspection jig 6 is provided at a predetermined position within the moving range of the table 4. As shown in FIG. 2, the board inspection jig 6 includes a pin board 6.
b is provided, and a plurality of probe pins 6a are implanted on the pin board 6b.

The driving of the board inspection jig 6 and the servomotors 2a and 3a of the moving means is controlled by the CPU 5 as control means. In addition, according to the present invention, a camera (for example, a CCD camera) 11 and its image processing means 12 are provided. The camera 11 is preferably arranged adjacent to the board inspection jig 6 and captures an image on the table surface. The image data processed by the image processing means 12 is sent to the CPU 5.

According to the present invention, the amount of movement of the table 4 is controlled in the following manner in order to eliminate the influence of the "skew" of each of the moving means 2 and 3. First, as shown in FIG. 3, the surface of the table 4 is partitioned into a plurality of blocks.

This section is preferably an equal section. In this embodiment, it is divided into 20 blocks in a 4 × 5 matrix. This partitioning is performed virtually, for example, in the CPU 5, but a line may be actually drawn on the surface of the table 4. According to this embodiment, the dent sheet 4a is placed on the table 4.

Then, each servo motor 2
The position designation data is output to a and 3a, and is moved to below the table 4. The position designation data is preset in the CPU 5 by an operation unit (not shown).
For example, it is represented by X, Y coordinate values such as (X1, Y1).
The position designation data is set for each block.

As a result, each block is sent to a position immediately below the pin board 6b in a predetermined order, and a dent is made on the dent sheet 4a by the probe pin 6a for each block as the pin board 6b is lowered.

The number of the dents may be one for each block or a plurality of dents. Then, move each block to the position directly below the camera 11
The dent is imaged by the camera 11, and the position data of the dent is obtained by the image processing means 12. The dent position data is given to the CPU 5.

In the CPU 5, the position designation data previously sent to each of the servomotors 2a and 3a (the position data where a dent should be originally made) and the dent position data (the position data of the dent actually made) ) Is calculated, and the difference is held as offset data.

Then, at the time of the circuit board inspection performed thereafter, the CPU 5 controls the amount of movement of the X-axis moving means 2 and the Y-axis moving means 3 by adding the offset data to the position designation data. Thereby, each moving means 2, 3
Is corrected, and accurate control in μ units becomes possible.

When the circuit board D to be inspected is the multiple board described above, it is preferable to divide the table 4 into a plurality of blocks in accordance with each circuit board forming area.

While the present invention has been described with reference to specific embodiments, all modifications, alterations, and equivalent techniques that can be easily conceived by those skilled in the art are included in the present invention. For example, in the above embodiment, the dent position data is obtained by the image processing means 12 and the difference between the dent position data and the position designation data is obtained by the CPU 5.
The deviation between the coordinate position where a dent is formed due to the design and the position of the dent actually hit may be measured.

In the above embodiment, the dent sheet 4a is placed on the table 4. However, instead of the dent sheet 4a, a thin coating film may be formed on the table 4 by spraying, for example. . In some cases, a dent may be directly formed on the table 4.

Although the dents are formed by the probe pins, the probe pins are easily damaged and are expensive, so other pins may be used instead of the dents. Although the drive sources of the X-axis moving means 2 and the Y-axis moving means 3 are the servomotors 2a and 3a, the driving sources are not limited to these.

[0032]

As described above, according to the present invention,
Prior to the inspection of the circuit board, the XY table surface is divided into a plurality of blocks, and the XY table is moved to the position of the board inspection jig based on preset design position designating data. After moving and making a dent for each block with a probe pin, the dent of each block is imaged with a camera, the dent position data is obtained by image processing means, and the dent position data and position designation data are obtained. Is calculated and held as offset data, and in the subsequent circuit board inspection, the offset data is added to the position designation data to control the table moving means, so that it is present in the table moving means. XY table can be corrected, and the XY table can be positioned with high accuracy.

[Brief description of the drawings]

FIG. 1 is a schematic view schematically showing one embodiment of the present invention.

FIG. 2 is a side view showing a part of a board inspection jig from the above embodiment.

FIG. 3 is a plan view showing a state where an XY table surface is divided into a plurality of blocks in the embodiment.

FIG. 4 is a schematic diagram showing a conventional example.

FIG. 5 is an explanatory diagram for explaining “skew” of an axis existing in a table moving unit.

[Explanation of symbols]

 2 X-axis moving means 3 Y-axis moving means 4 XY table 5 CPU (control means) 6 Board inspection jig 11 Camera 12 Image processing means D Circuit board to be inspected (multi-circuit board)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tsuneaki Takizawa 81 Sakuramachi, Koizumi, Ueda-shi, Nagano F-term (reference) 2G011 AC06 AE01 AF06 AF07 2G014 AA02 AA03 AA08 AB59 AC10 2G032 AA00 AE01 AE04 AE12 AF01 AJ04 AK03

Claims (2)

[Claims] A table on which a circuit board to be inspected is mounted; a table moving means for moving the table in the X-axis direction and the Y-axis direction; and a table moving means provided at a predetermined position within a moving range of the table. A board inspection jig having a probe pin selectively contacting an inspection circuit board; and a control means for controlling operations of the table moving means and the board inspection jig. A control method of a circuit board inspection apparatus for controlling an amount of movement of a table when the table is moved to a position, comprising a camera for imaging the table surface and image processing means for the camera, and dividing the table surface into a plurality of blocks. Then, the table is moved to the position of the board inspection jig based on design position designation data set in advance in the control means, and the table is moved. After making a dent for each of the blocks with a cubing pin, the dent of each of the blocks is imaged by the camera, and the dent position data is obtained by the image processing means. Calculating a difference between the position data and the position designation data, and thereafter, the control means controls the table moving means by adding the difference data to the position designation data; Method. 2. In the case where the circuit board to be inspected is a multiple board circuit board having a plurality of circuit board formation regions,
2. The control method according to claim 1, wherein, when the table surface is divided into a plurality of blocks, the plurality of circuit boards are divided in accordance with a plurality of circuit board formation regions.