JPH04203916A - Inspecting method of external appearance - Google Patents

Abstract

PURPOSE:To execute determination efficiently by providing a first inspecting means for inspecting the quality of an external appearance and a second inspecting means for inspecting it precisely and by registering data of the first inspecting means on the basis of the result of determination of the quality by the second inspecting means. CONSTITUTION:Since the data on solders x1 and x2 are not registered in a memory M1, determination of the quality is not executed by a first inspecting means 21. Therefore, the solders x1 and x2 are measured precisely by a second inspecting means 22 so as to determine the quality. Products are assorted into good and bad ones in a table K3, the solder x1 is determined as bad, while the solder x2 is determined as good, and they are registered additionally in the memory M1. In this way, the product of which the quality can not be determined by the means 21 is subjected to precise inspection by the means 22, and based on the result of the inspection, fresh data are registered additionally in the memory M1. By using these additional data from the next inspection onward, the inspecting capacity of the means 21 can be increased step by step.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an appearance inspection method, in which the appearance of an object to be inspected is judged to be good or bad based on quality judgment data taught by a computer. For inspection objects for which pass/fail judgment could not be determined, a detailed inspection is performed based on the pass/fail judgment precision data, and the inspection results are additionally registered in the pass/fail judgment data, thereby increasing the inspection ability. It is.

(Prior Art) After an object to be inspected is bonded to a board with solder, an appearance inspection is performed to determine whether the object is in good condition or not.

Conventionally, such appearance inspection has been carried out by visual inspection, but in recent years automatic inspection using optical means has become increasingly popular.

The above-mentioned appearance inspection is generally carried out using a camera, and the one shown in Japanese Patent Application Laid-Open No. 1-79874 has been proposed. This device is equipped with a top camera that observes the object to be inspected from vertically above, and a side camera that observes the object from diagonally above. It is designed to check for floating objects.

(Problems to be Solved by the Invention) As described above, the conventional means that combines a top camera and a sight camera has characteristics such as a wide inspection area and a fast inspection speed.

However, is the camera a two-dimensional plane? [However, since height information cannot be detected, visual inspections that require precise height information, such as solder visual inspections, cannot be performed.

Incidentally, a laser device is known as a means for obtaining precise height information. A laser device is a device that irradiates an object to be inspected with a very finely focused laser beam in a spot manner and detects the reflected light, and has the property of being able to accurately measure height. Therefore, if a laser device is used, precise visual inspection can be performed, but in this case, the laser beam must be scanned in the XY force direction and the entire surface of the object to be inspected must be irradiated with the laser beam, which takes a lot of time. There are some drawbacks.

Therefore, an object of the present invention is to provide a means for quickly and accurately inspecting the appearance of an object to be inspected using inspection means having different characteristics such as a camera or a laser device.

(Means for Solving the Problems) The present invention includes a first inspection means for inspecting the appearance of an object to be inspected based on pass/fail judgment data taught by a computer; a second inspection means for closely inspecting the appearance of the inspection object for which it could not be determined, based on precision judgment data taught by the computer, and a detailed inspection by the second inspection means; Based on the pass/fail judgment result, the inspection data of the first inspection means regarding this inspection object is added to the computer as pass/fail judgment data. It was designed to be recorded in sequence.

(Operation) According to the configuration described in 1-, the first inspection means performs an external appearance inspection of the inspection object and determines its quality. Further, for the inspection objects for which the quality cannot be determined by this visual inspection, a detailed inspection is performed by the second inspection means to determine the quality.

Based on the quality determination result of this detailed inspection, the inspection data of the first inspection means regarding the object to be inspected is additionally registered in the computer as quality determination data. By additionally registering test data in this way, the data amount of the computer gradually increases, and the test capability of the first test means can be gradually increased.

(Example) Next, the present invention will be described in detail with reference to the drawings.

Figure 1 is a diagonal 82 view of the visual inspection device, and shows
It is a table, and the substrates 2 set on its two sides are moved in the XY force directions. On this board 2, there are box-shaped test objects PA such as capacitor chips and resistor chips, and Q
An inspection object PB having leads such as FP and sop is mounted.

A one-piece camera 3 and four side cameras 4 are provided above the XY child table.

Reference numeral 5 indicates a ring-shaped top light source that is provided integrally with the camera 1 to the tube camera 3, and reference numeral 6 indicates a side light source that is provided below the sight camera 4. ) Irradiate light to r3. The top camera 3 observes the inspection objects PA, PB from vertically above, and the side camera 4 observes the inspection objects PA, PB from diagonally above to obtain planar two-dimensional image information of the inspection objects PA, PB. It's something you get. The camera 3.4 and the light a5.6 constitute a first inspection means.

7 is a laser device provided above the substrate 2, and 8 is a light receiving section. As shown in FIG. 3, this light receiving section 8 is a PSD
It includes a position detection element 8a and a condensing element 8b. The position detection element 8a receives the laser beam emitted from the laser device 7 and reflected by the inspection object P, and obtains height information of the inspection object P from the incident position of the laser beam. Two light receiving sections 8 are provided in pairs, and the substrate 2 is
While moving in the y-force direction, height information along the xy-force direction can be obtained by each element 8. Further, the laser device 7 has a built-in mirror 9, and by controlling the angle of the mirror 9, the laser beam is scanned along the solder fillet H and the like. The laser device 7 and the light receiving section 8 constitute a second inspection means. As the second inspection means, a contact type three-dimensional measuring device or the like can also be applied.

10 is a computer, each camera 3.4 and the light receiving section 8 are connected to this computer 10, and the camera 3.
．． Based on the information obtained from 4 and the light receiving section 8, calculations of the solder shape, quality judgment, etc. are performed.

The camera 3.4 has characteristics such as a wide inspection area and a fast inspection speed. But camera 3.4 is 2
This method can only detect dimensional planar information and cannot measure height, so it has the disadvantage that it is not possible to accurately measure the shape of the solder fillet H. On the other hand, the inspection means consisting of the laser device 7 and the position detection element 8a irradiates the object to be inspected spot-wise with extremely finely focused laser light and detects the reflected light. Although it can measure height, it has disadvantages such as not being able to recognize two-dimensional information all at once and slow inspection speed like camera 3.4.

Therefore, in this method, the appearance of an object to be inspected is inspected by selectively using the camera 3.4 and the laser device 7, which have the advantages and disadvantages described above. Explain.

FIG. 2 shows the quality determination data taught to the computer 10 by the first inspection means 3-6. The A group is a box-shaped electronic component PA, and the B group is an electronic component PB having a lead.

Ha in Group A is a solder with a good appearance.

First, in FIG. 2(a), when the top light a5 is turned on and observed with the top camera 3, the light irradiated onto the normal solder Ha is reflected to the side. Therefore, the reflected light does not enter the top camera 3, and the dark portion 1-1 aa of the solder is observed by the top camera 3, and it can be determined that the appearance of the solder is good.

In addition, in FIG. 6(b), Hb is also a good solder. The light irradiated onto the upper surface of the solder 11b is reflected upward and enters the camera 3. Therefore, dark part 1-1
A bright portion Hbb is observed inside b a.

In addition, in the same figure (C), the solder Hc has not yet arrived. The light irradiated onto the solder Hc from above is reflected upward and enters the camera 3, so that the entire solder Hc is observed as a bright portion Hca.

In addition, in the same figure (d), when the inspection object PA is standing due to the surface tension when the solder melts and solidifies, one solder Hdl is observed as a dark area Hdla, and the other solder Hd2 is observed as a bright area. Observed as Hd 2 a.

Next, group B will be explained. L beam is -1.

In the figure (a), since the solder Hf beam L is sufficiently adhered to the substrate, the appearance is good. The light emitted from above is reflected diagonally upward and does not enter the camera 3, so it is observed as a dark area Hfa.

The inspection object PB shown in FIG. 2B has a J-shaped glued L. Since the solder Hg sufficiently adheres the leads L to the substrate, the appearance is good.

When the side light @i6 is turned on and observed using the side camera 4, a bright portion Hgb is observed inside the dark portion Hga.

In the same figure (c), the solder Hh is not yet adhered, and the light irradiated from above enters the camera 3 above and is observed as a bright portion Hha. In addition, in FIG. 3(d), the lead L is floating from the solder Hi. In this case, a bright portion Hib is observed inside the dark portion Hia.

As mentioned above, by switching the camera 3.4 and the light source 5.6, various inspections can be performed, and of course there are also other inspections described in the above-mentioned Japanese Patent Application Laid-Open No. 1-79874. As such, it is possible to inspect for lifting or misalignment of the inspection object, as well as for turning it upside down or for missing items.

Moreover, the area, length, etc. of dark parts and bright parts may be used as quality determination data.

Therefore, if the quality determination data shown in FIG. 2 is registered in the memory Ml of the computer 10 (see FIG. 5), the appearance inspection of the electronic component P can be performed by the first inspection means 3 to 6. can. In this case, the appearance inspection is performed by checking whether the image of the inspection object captured by the camera 3.4 matches with which image shown in FIG. 2. Then, if it matches (a) and (b) of group A and (a) and (b) of group B, the appearance is judged to be good, and (c) and (d) of group A and (a) and (b) of group B (C) and (d), the appearance is judged to be poor.

FIG. 4 shows the solder H measured by the laser device 7. In this case, the upper surface of the board 2 is set as the reference plane GND, and the height Hx of the solder l (is measured). Excessive solder or insufficient solder is determined by comparison with the thickness Ht of the inspection object P. For example, , 1.5 times the thickness Ht of the inspection object P is set as the upper limit height ■11, and if the height l-1x of the solder H is greater than that, it is determined that there is excess solder and the appearance is defective. For example, 0.5 times the thickness Ht is set as the lower limit height H2, and if the height 11 .

Also, the fillet saw l-angle is a predetermined angle θr (for example, 20
°), and if the measured angle θX is less than that, the solder fillet is judged to be too thin and defective. Alternatively, if there is time, the three-dimensional shape of the solder H may be precisely measured by repeatedly scanning the laser beam in the XY force directions.

Precise measurement using the laser device 7 has the disadvantage that it requires a long time, but it has the advantage that height information of the object to be inspected can be obtained, so the three-dimensional shape of the object to be inspected can be measured and accurate judgments can be made. Therefore, the data described with reference to FIG. 4 is registered in the memory M2 (see FIG. 5) of the computer 10 as precision data for quality determination. FIG. 4 exemplarily shows the fine quality data.

FIG. 5 shows the visual inspection system. In the figure, 2 is a board to be inspected. 21 is the camera 3.4 mentioned above,
The first inspection means consists of a light source 5.6. 1 on the table is an image of the first inspection means 21. Reference numeral 22 denotes a second inspection means composed of the laser device 7 and the position detection element 8.

2 in the table shows the shape of solder measured by the second inspection means 22. K3 is allocated to the table. M1 and M2 are parts 210 of the computer, and the quality determination data shown in FIGS. 2 and 4 are registered. A zero-order inspection method will be described.

Place the board 2 on the XY tape/l/I and attach the camera 3.4.
The electronic component P is observed by switching the light sources 5 and 6. Then, the image captured by the camera 3.4 is compared with the quality determination data registered in the memory M1, and the quality is determined. That is, the image captured by camera 3.4 is
If the solder is matched with the image that is considered good in the figure, the appearance of the solder is judged to be good. Furthermore, if the solder is matched with the image determined to be defective in FIG. 2, the solder is determined to be defective.

There are various shapes of solder, and it is difficult to register the image data of all solders in the memory M1 in advance, and only representative data is registered in the memory M1. Therefore, there are solders that cannot be determined to be good or bad using only the pre-registered data in the memory M1.

In table 1 in FIG. 5, xl and x2 indicate solders for which the first inspection means 21 cannot determine whether the solder is good or bad because no data is registered in the memory M1. Therefore, such solders x1 and x2 are precisely measured by the second inspection means 22, and a pass/fail judgment is made based on the quality judgment precision data described with reference to FIG.

Then, sort out the good and defective items on the table in 3 categories,
Images of solders x1 and x2 are additionally registered in memory Ml.

The solder x1 is defective and is additionally registered in the defective part 2 of the A group of the memory M1. Furthermore, solder x2 is good and is additionally registered in the good part (2) of group B in memory M1. (e) in FIG. 2 shows that the images of the solders x1 and x2 are registered as new quality determination data for the first inspection means 3-6.

In this way, if the first inspection means 21 cannot determine the quality of the product, the second inspection means 22 performs a detailed inspection, and based on the results, new data is additionally registered in the memory M1, and the next time By using this added data from the inspection, the inspection ability of the first inspection means 21 can be gradually increased, and ultimately it will be possible to judge the quality of almost all inspection objects.

Although the above embodiments have been described with reference to the case of determining the quality of the appearance of solder, the present invention can also be used to determine the type of electronic components, to inspect for chips, and to inspect the shape and flaws of metals, tablets, etc. Furthermore, it can be applied to visual inspection such as fruit sorting inspection, and its field of use is not limited to the above embodiments.

(Effects of the Invention) As explained above, the present invention includes a first inspection means for inspecting the appearance quality of an object to be inspected based on quality determination data taught by a computer; A second inspection means for closely inspecting the appearance of the inspection object for which the quality of the inspection object could not be determined based on the precision data for quality determination taught by the computer;
Based on the pass/fail judgment result of the detailed inspection by the second inspection means, the inspection data of the first inspection means concerning the object to be inspected is additionally registered in the computer as pass/fail judgment data. , it is possible to efficiently determine the quality of the object to be inspected. In particular, according to this method, the inspection ability of the first inspection means is gradually increased, and ultimately, the first inspection means can judge the quality of almost all inspection objects at high speed and accurately. can be done.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a perspective view of an external appearance inspection device, Fig. 2 is an illustrative view of pass/fail judgment data,
FIG. 3 is a side view of the laser device, FIG. 4 is an illustrative diagram of precision data for pass/fail determination, and FIG. 5 is a block diagram of the inspection system. 3.4...Camera 7...Laser device 10...Computer 21...First inspection means 22...Second inspection means

Claims (2)

[Claims] (1) A first inspection means for inspecting the quality of the appearance of the object to be inspected based on the quality determination data taught by the computer; and for the object to be inspected whose quality could not be determined based on the quality determination data; A second inspection means for closely inspecting the quality of the external appearance of the object to be inspected based on the precision data for quality determination taught by the computer; An appearance inspection method characterized in that inspection data of the first inspection means regarding the object is additionally registered in the computer as pass/fail determination data. (2) The first inspection means is a camera, the quality determination data is image data of the planar shape of the object to be inspected, and the second inspection means is a laser means,
2. The external appearance inspection method according to claim 1, wherein the precision data for quality determination includes height information of the object to be inspected.