JPH08159715A - Inspection instrument for deviation of mounting position of electronic component - Google Patents

Abstract

PURPOSE: To enable the mounting deviation to be inspected recognizing the mounted position of a part, regardless of the amount and quality of a solder by detecting the package position of an object to be inspected and comparing it with the package position in the normal mounting to examine a positional deviation. CONSTITUTION: At a package illuminance recognizing section 91, a window for recognizing package illuminance is generated at the center position in the normal mounting of a part 4 to be inspected to obtain an illuminance data of a package part of an angular chip part. At a package position recognizing section 92, a position outside a range of illuminance obtained by the illuminance recognizing section 91 is detected from the center position in the normal mounting of the part 4 to be inspected. At a mounting deviation judging section 93, a difference is inspected between the width and length in the longitudinal direction detected of the part and those specified originally thereof at a package position of the part to be inspected detected. When the difference is large, non-mounting deviation without the part to be inspected is determined. Thereafter, a comparison is performed between the package position and the position of the end of the part mounted normally to determine the distance and when a separation therebetween is large exceeding a threshold, a mounting deviation is determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for picking up an image of an object to be inspected with a television camera or the like and detecting a positional deviation of the object to be inspected from the video signal thereof. Measure the shape and dimensions,
The present invention is applied to an inspection device that determines the quality of mounting.

[0002]

2. Description of the Related Art Here, an example of a rectangular chip component mounted on a printed wiring board as an inspection target will be described with reference to FIG. First, an image of each stage illumination in the field of view of the TV camera 6 is taken centering on the inspection target part. A part of this is shown in FIG. From this image, the inspection window 1 in a form that matches the land that is the soldering portion of the chip component 4 to be inspected
3 is formed. In this inspection window, defect inspections such as excess or deficiency of solder and positional deviation are usually performed.

Of these, the inspection of the positional deviation uses two methods.

First, as shown in FIG. 6, the width W of the electrode portion 11 of the rectangular chip part in the inspection window corresponding to the land is detected, and if it is relatively shorter than the actual electrode width, the mounting is performed. It is determined that there is a displacement.

The second is the land 12 as shown in FIG.
In parallel with the above, the positional deviation inspection window 13 is set. If the electrode portion 11 of the rectangular chip component is detected in the positional deviation inspection window, it is determined that the mounting positional deviation has occurred. In this method of detecting the electrode portion of the rectangular chip component, since the electrode portion is flat and has a high light reflectance, a group having particularly high reflection is detected and estimated as the electrode portion.

[0006]

As described above, the mounting position deviation inspection of the electronic component is carried out based on the mounting position of the lead within the soldering point or the presence or absence of the lead in the lead deviation inspection window set beside the land. Are doing. However, if there is too much solder in the soldering inspection point, it will not be possible to recognize even the presence of leads, and the misalignment inspection window set beside the land will have various patterns such as wiring patterns and silk. Therefore, it is a factor that reduces the detection capability such as erroneously detecting a lead.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention detects the position of a package (main body, that is, not the lead portion) of a component to be inspected by performing a displacement inspection of the component to be inspected. The position shift inspection is performed by comparing with the package position in the case of regular mounting. In this package detection method for the inspection target component, the range of illuminance data at the center of the regular mounting position of the target component is obtained. Since the package illuminance of the electronic component to be inspected is uniform, it is possible to obtain a limited illuminance range. This is a method of detecting the package position by detecting the position where the illuminance data deviates from this range.

[0008]

Since the illuminance data on the package is uniform, it can be seen that the illuminance data on the package changes in any case on the printed circuit board and is not on the package of the component to be inspected. Further, since the inspection is performed by using the data of the package portion of the inspection target component, the mounting position of the component can be recognized regardless of the amount and quality of solder, and the mounting deviation inspection can be performed.

[0009]

Embodiments of the present invention will be described with reference to the following drawings.

The mounting deviation inspection apparatus of the present invention is shown in FIGS.
It will be described with reference to FIG.

The inspection target is assumed to be a rectangular chip part on a printed wiring board.

The light emitted from the illuminator 5 is reflected by the rectangular chip 4 to be inspected and received by the television camera 6. Next, the mounting deviation of the target component of the present invention is inspected by the inspection device 9. Here, when the mounting deviation inspection is performed, the video signal input by the television camera 6 is used.

First, in the package illuminance recognizing section 91, as shown in FIG. 1, the package illuminance recognizing window 1 is located at the center position when the inspection target component is properly mounted.
4 is created, and the illuminance data of the package part (main body) of the rectangular chip part is obtained. Since the package is flat but not a mirror surface, uniform data can be obtained without reflecting light. At this time, in order to remove noise such as characters on the package, a video data range (not shown) occupying 80% of the package illuminance recognition window is recognized.

Next, in the package position recognition section 92,
For example, when recognizing the mounting position in the component width direction, the illuminance obtained by the package illuminance recognizing unit 91 in the b and c directions from the center position a when the inspection target component is properly mounted as shown in FIG. The position (h1, h2) outside the range is detected. Similarly, when recognizing the mounting position in the vertical direction of the component,
The position (v1 and v2 not shown) where the data outside the range of the package illuminance appears from is detected.

In the mounting deviation determining section 93, the detection widths h1 and h2 in the component width direction are detected at the detected package position of the target component.
Is not much different from the original part width, and it is also checked in the vertical direction whether the detected lengths v1 and v2 are different from the original part length. If the difference is large, it is determined that the detected one is not the package, that is, there is no target component, and it is a mounting deviation. Then, in the package position recognition, the detected package position (h1, h2, v1, v2) is compared with the distance between the component end positions in the case of regular mounting, and if the distance is equal to or more than the threshold value, it is determined that there is mounting deviation. .

Next, an embodiment in which the mounting deviation inspection device 9 of the present invention is used in a step illumination type inspection device will be described with reference to FIG.

Inspecting electronic components on a printed wiring board,
Well-known inspection method by multi-stage illumination (for example, Japanese Patent Publication 5-2
1403).

FIG. 4 shows the basic system configuration of this multi-stage lighting type soldering inspection apparatus.

In the figure, the light emitted from the multistage illuminator 5 having different projection angles to the inspection object 4 is reflected by the inspection object and received by the television camera 6. The video signals obtained by switching the illumination up and down are combined in the code generation unit 7, and a tilt code (for example, 1 to 1) indicating the angle of the target surface is combined.
8) is generated. This tilt code is a direction perpendicular to the inspection object, and the illumination from above returns high reflected light at the flat part, and the illumination from diagonally increases the reflected light at the part with a high inclination angle. Is a combination of images obtained by illuminating, and the angle of the target surface is represented by a code. In this way, the obtained inclination code is sent to the recognition processing unit 8 as an inclination code pattern arranged according to the shape of the inspection object, and the three-dimensional shape of the inspection object is recognized and the quality is determined.

It is assumed that the object to be inspected is a rectangular chip part on the printed wiring board, as in FIG.

The light emitted from the illuminator 5 is reflected by the inspection object 4 and received by the television camera 6. The image data obtained by switching the illumination of each stage is generated by the code generation unit 7 into an inclination code indicating the angle of the target surface within the inspection window having a shape matching the land. Next, the recognition processing unit 8 performs a soldering inspection, but before that, a mounting deviation inspection 9 of the target component of the present invention is performed. Here, when performing the mounting deviation inspection, the video signal input by the television camera is used.

First, in the package illuminance recognition section 91, as shown in FIG. 1, the package illuminance recognition window 1 is located at the center position when the inspection target component is properly mounted.
4 is created, and the illuminance data of the package part (main body) of the rectangular chip part is obtained. In this case, if image data obtained by illumination from above is used, uniform data can be obtained without reflecting light because the package is flat but not a mirror surface. At this time, in order to remove noise such as characters on the package, a video data range (not shown) occupying, for example, 80% in the package illuminance recognition window is recognized. The following operation is the same as that of the embodiment shown in FIG.

In the package position recognition, the distance between the detected package position and the component end position in the case of normal mounting is compared, and if the distance is equal to or more than the threshold value, it is determined that there is mounting deviation.

Although the image data obtained by the illumination from above is used here, it is also possible to use the illumination at an angle due to the reflection characteristics of the target component.

[0025]

As described above, the package position can be easily recognized by detecting the illuminance data outside the illuminance range on the package as a method for inspecting the mounting deviation of the inspection target component. Since the displacement is inspected by comparing with the regular mounting position, the mounting displacement can be inspected without being affected by the pattern on the printed circuit board, the shape of soldering, the amount of solder, etc. Has a significant effect on

[Brief description of drawings]

FIG. 1 is a model diagram of package illuminance recognition for explaining the present invention.

FIG. 2 is a model diagram of package illuminance recognition for explaining the present invention.

FIG. 3 is a basic configuration diagram of an inspection device according to an embodiment of the present invention.

FIG. 4 is a basic configuration diagram of a multi-stage illumination type visual inspection apparatus according to an embodiment of the present invention.

FIG. 5 is a model diagram of slit type mounting deviation detection for explaining a conventional technique.

FIG. 6 is a model diagram of mounting displacement detection based on an electrode detection width for explaining a conventional technique.

FIG. 7 is a basic configuration diagram of a conventional inspection device.

[Explanation of symbols]

4 Inspection target (square chip), 5 Illuminator, 6 Light receiving sensor (TV camera), 7 Code generator, 8
Recognition processing unit, 9 mounting deviation inspection device, 91 package illuminance recognition unit, 92 package position recognition unit,
93 mounting deviation determination section, 11 rectangular chip electrode section,
12 lands, 13 inspection windows, 14 package illuminance recognition windows,

Claims (2)

[Claims] 1. An apparatus for imaging an inspection object and inspecting mounting deviation of the inspection object from the obtained image information, moving a window for extracting a part of the image of the inspection object on the inspection object. Then, the mounting position shift inspection of the electronic component is characterized in that the length of the obtained image of the inspection target is compared with the length of the regular mounting position of the inspection target, and the inspection result is determined from the obtained result. apparatus. 2. A plurality of sets of illumination light sources having different projection angles to an inspection target, and a light receiving sensor for receiving reflected light from the inspection target by the illumination light sources as an illuminance distribution and outputting it as electrical signal data. And a recognition process capable of recognizing the three-dimensional shape of the inspection object based on the distribution state of the output electric signal, the illuminance information on the inspection object is recognized in a mounting deviation inspection device having Detecting illuminance information deviating from the illuminance information, moving a window for extracting a part of the image of the inspection object on the inspection object,
An electronic component mounting position deviation inspection device, characterized in that the length of the obtained image of the inspection target is compared with the length of the regular mounting position of the inspection target, and the inspection result is determined from the obtained result.