JP3511437B2 - Package recognition method in automatic sealing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic sealing device for automatically welding a lid to a container (package) of a circuit element such as an IC, a transistor, a crystal oscillator, etc., and particularly to a position of the package and the lid. The present invention relates to a package recognition method using image recognition for matching.

[0002]

2. Description of the Related Art The sealing work of circuit elements such as ICs, transistors and crystal oscillators is carried out as a final manufacturing step after the circuit elements are housed in a package and wiring and test adjustment work is performed. Examples of the sealing method include resin sealing and hermetic sealing. The airtight sealing method is a method in which an element is housed and fixed in a metal or ceramic package, and a lid is placed in a dry inert gas atmosphere to completely seal the element. According to this airtight sealing method, impurities such as moisture do not enter and the element and the sealing material do not come into direct contact with each other, so that the effect of thermal stress is small and higher sealing reliability can be obtained compared to resin sealing. You can

There is an automatic sealing device for automatically welding a lid to a package by using a micro parallel seam joining method which is one of the hermetic sealing methods. FIG. 8: is a figure for demonstrating the sealing work by the conventional automatic sealing device. As shown in FIG. 8A, a seal ring 31 made of Kovar material plated in advance with gold is brazed around the sealing portion (the portion in which the elements are stored) of the package 30. Then, the position of the seal ring 31 is calculated by capturing an image with an image recognition device (not shown), and the lid 32 made of a metal plate (usually a nickel-plated Kovar material) and the seal ring 31 are positioned (see FIG. 8B. )).

Then, a pair of roller electrodes 33 are applied to the opposite edge portions of the lid 32, and an appropriate pressure is applied. When an electric current is applied between the electrodes in this state, Joule heat is generated in the contact portion (electrode 33 and lid 32), and the heat is transmitted to the contact portion between the lid 32 and the seal ring 31, whereby the lid 32 and the seal ring 31 The plated layers are melt-bonded to each other. Further, by rolling the roller electrode 33 along the edge of the lid 32 while passing a current, the sides of the lid 32 facing each other can be simultaneously seam-joined. Normally the package is rectangular, so
After joining the X sides as shown in (c), the Y sides are joined similarly as shown in FIG. 8 (d). In this way, the lid can be welded to the package.

By the way, in such an automatic sealing device, the seal ring 31 and the lid 32 are detected by using image recognition in which the image of the seal ring 31 is taken in and the position is calculated.
Is being positioned. At this time, if the package is not placed on the tray that carries the package or if the package is defective, welding should not be performed. However, the package is judged to be defective if the recognition failure occurs due to disturbance (vibration of the device itself or the influence of light from the outside), or if the contour of the extracted seal ring is discontinuous (seal ring When the contour is interrupted due to a scratch or the like that crosses. If the seal ring has scratches or stains, the extracted contour will undulate, but unless the contour is discontinuous, the package was not judged to be defective.

Further, since the tray is provided with a recess having a shape similar to the outer shape of the package, and the package can be accommodated in this recess, this is mistakenly recognized as a package, and it is judged as a good product. I had to make a decision. Further, what is to be recognized is usually the outer contour of the seal ring, but image recognition may not be stable due to the above-mentioned disturbance or the shape of the package. In such a case, the inner side of the seal ring may be recognized. The software was modified so that it would be recognized as.

[0007]

As described above, in the conventional automatic sealing device, there is no settable threshold value for judging whether the package is a good product or a defective product. However, there is a problem in that the threshold value cannot be adjusted so that an appropriate determination can be made by the user, and thus an inappropriate determination or erroneous recognition occurs. Also, in order to switch between the outer contour of the package as the recognition target and the inner contour as the recognition target,
Software specialists had to modify it, and once it was set, there was the problem that all types of packages would have to be measured either. The present invention is
The first object of the present invention is to provide a package recognition method which is made to solve the above-mentioned problems, and which can appropriately determine whether a product is good or defective at the time of image recognition. A second object is to provide a package recognition method capable of easily switching the contour of the package to be recognized.

[0008]

According to a first aspect of the present invention, a package is imaged by a camera, contour data of the package is extracted from a grayscale image of the package, and the package is extracted from the contour data. Obtain the length of each side of, and extract the straight line part on each side from the contour data,
The ratio of the straight line portion to the length of the obtained side is calculated for each side, and the ratio of the calculated straight line portion is compared with the determination reference value,
This is to determine whether the package is non-defective. In this way, it is possible to determine whether the package is a non-defective product by calculating the ratio of the straight line portion in the contour data of the package for each side and comparing this with the determination reference value.

Further, as described in claim 2, the lid size indicating the size of the lid and the recognition size for selecting the outline of the package to be recognized are set in advance, the package is imaged by the camera, and the image is picked up. When extracting the contour data of the package from the grayscale image of the package, compare the set lid size with the recognition size,
Based on the comparison result, it is determined whether to extract the outer contour data or the inner contour data of the package. By setting the lid size and the recognition size in this way, it is possible to switch between the outer contour of the package and the inner contour of the package.

[0010]

DETAILED DESCRIPTION OF THE INVENTION

1. Embodiment 1. FIG. 1 is a flow chart for explaining a package recognition method according to the first embodiment of the present invention, and FIG. 2 is a block diagram of an automatic sealing device used in this package recognition method. In FIG. 2, the transport mechanism unit 4 transports the tray on which the package is placed to the jig table 3 and also transports the lid directly above the package. The bonding head moving mechanism 5 lowers the bonding head (not shown) onto the package, and the welding power source 6 supplies a current to the roller electrode of the bonding head. And the sequencer 7
Controls the jig table 3, the transport mechanism 4, the joining head moving mechanism 5, and the welding power source 6, and the host computer 8 controls the entire automatic sealing device.

Next, a package recognition method in such an automatic sealing device will be described with reference to FIG. First, the transfer mechanism 4 transfers the tray on which the package is placed to the jig table 3, and the camera 1 moves the jig table 3
The upper package is imaged from above (step 10 in FIG. 1).
1). The image recognition device 2 digitizes the grayscale image captured by the camera 1 and then binarizes it. And
With the seal ring size indicating the preset outer size of the seal ring, data of an inappropriate size is deleted and the contour of the seal ring is extracted (step 10).
2).

Next, the image recognition device 2 calculates the inclination and the center of gravity of the seal ring in the horizontal plane from the extracted contour data of the seal ring (step 103). FIG. 3 is a diagram for explaining a method for calculating the inclination of the seal ring,
White circles in the figure are the extracted contour data (dots).
The tilt of the seal ring in the θ direction is obtained as follows.

First, the frequency of inclination of each line segment connecting contour data is taken as shown in FIG. Since the four regions with high frequency correspond to the sides A to D of the seal ring shown in FIG. 3, respectively, the average values of the inclinations of the regions with high frequency in FIG. Approximate the position.

Next, the respective sides A to D of the seal ring are determined by the least square method from the data existing within a fixed range α centered on this approximate side. With this, the inclination of the seal ring in the XY plane is obtained. The center of gravity O of the seal ring is obtained from each of the determined sides A to D. In this way, the position of the seal ring can be determined.

Next, the image recognition device 2 obtains the proportion of the straight line portion in the contour data for each of the determined sides A to D (step 104). FIG. 5 is a diagram for explaining a method of calculating the ratio of this straight line portion. In addition, in FIG. 5B, only one side A of the seal ring is enlarged. First, the image recognition device 2 obtains the total length including the curved corners for each of the sides A to D, and sets these as LA, LB, LC, and LD (FIG. 5A).

Subsequently, as shown in FIG. 5B, a constant range β is set in the width direction with the side A as the center. The straight line portion on the side A including the corner portion is a portion formed by data continuously existing in the range β for a predetermined length (for example, 3 dots) or more. Therefore, the portion E in FIG. 5B is not included in the straight line portion. Thus, the length JA of this straight line portion is obtained. Then, the ratio (JA / LA) of the length JA of the straight line portion to the total length LA of the side A is calculated. The above calculation is performed for each of the sides A to D.

Next, the image recognition device 2 compares the judgment reference value input from the keyboard 9 in advance with the calculated proportion of the straight line portion to judge whether the package is non-defective (step 105). At this time, if the proportion of the straight line portion is smaller than the determination reference value, it is determined as a defective product. Then, this defective product is automatically taken out by the transport mechanism 4 (step 106).

Further, when the proportion of the straight line portion is judged to be a non-defective product when it is equal to or larger than the judgment reference value, the jig table 3 is moved to X, by the control of the sequencer 7 based on the decided seal ring position.
While moving in the Y direction and rotating in the θ direction, the positions of the seal ring and the lid are aligned (step 107). Then, the bonding head moving mechanism 5 lowers the bonding head onto the package, and the welding power source 6 supplies a current to the roller electrode of the bonding head, whereby the lid is welded to the package (step 108).

As described above, in the present embodiment, the ratio of the calculated straight line portion is compared with the judgment reference value to judge whether the package is non-defective or not. By setting a desired value for the ratio), it is possible to make an appropriate determination according to the type of package, the imaging condition, and the like. In addition, the waviness of the contour caused by scratches or stains on the seal ring is excluded from the straight line portion, and the ratio of the straight line portion falls below the judgment reference value. Can be detected as a defect.

Also, as shown in FIG. 6, the recess 23 of the tray 22 on which the package is placed has the same shape as the seal ring 21, but the proportion of the above-mentioned straight line portion is changed by the relief 24 for taking out the package. Lower than the package. Therefore, by properly setting the determination reference value, the depression 23 of the tray will not be erroneously recognized as a package.

1. of the embodiment Also in the present embodiment, the configuration of the automatic sealing device is the same as that in FIG. 2, and the package recognition method is almost the same as that in FIG. In the first embodiment, only the outer contour or the inner contour of the seal ring is always extracted, but in the present embodiment, the outer contour or the inner contour is automatically switched. .

For this switching, the operator using the automatic sealing device operates the keyboard 9 to input the lid size indicating the vertical and horizontal (X, Y) sizes of the lid, and the recognition size. If there is no problem in image recognition using the outer contour of the seal ring, the operator sets the vertical and horizontal sizes of the outer contour of the seal ring as recognition sizes.

When the package recognition is not stable when the outer contour of the seal ring is used, the vertical and horizontal sizes of the inner contour of the seal ring are set as recognition sizes. As a result, in step 102 of FIG. 1, the image recognition device 2 compares the input lid size with the recognized size, and when the recognized size is equal to or larger than the lid size, extracts the outer contour of the seal ring and determines the recognized size. If it is smaller than the lid size, the inner contour of the seal ring is extracted.

Due to the weldability, the lid is smaller than the outer size of the seal ring and larger than the inner size. Therefore, by setting the lid size and the recognition size as described above, it is possible to automatically switch which of the inside and the outside of the seal ring is to be recognized. In step 102, the contour of the seal ring is identified as follows. FIG. 7 is a diagram for explaining a method of identifying the contour of the seal ring.
Although the image data is a set of dots, it is displayed as a line here.

When the package is imaged, the seal ring 2
The portion 5 has a high luminance level, and the inside and the surroundings have a low luminance level. As a result, when scanning the binary image data shown in FIG. 7 in the direction of the arrow, the level of the image data changes from “dark” to “bright” to “dark”. Therefore,
When the image data changes from "dark" to "bright", it is the inner contour of the seal ring, and when it changes from "bright" to "dark", it is the outer contour of the seal ring. In this way, the image recognition device 2 can select the outer contour or the inner contour of the seal ring. The operation after step 103 is similar to that of the first embodiment.

[0026]

According to the present invention, the ratio of the straight line portion in the contour data of the package is calculated and compared with the judgment reference value to judge whether the package is non-defective or not.
By setting an appropriate value as the determination reference value, it is possible to make an appropriate determination according to the type of the package, the imaging conditions, etc., and prevent the tray from being erroneously recognized as the package. Further, since the waviness of the contour caused by scratches or stains on the seal ring is removed from the straight line portion, even if the contour has continuity, these can be detected as defective products.

Further, by setting the lid size and the recognition size, it is possible to easily switch whether the outer contour of the package is to be recognized or the inner contour is to be recognized. Switching can be performed according to conditions and the like, and the recognition target is not fixed to the outer or inner contour of the package.

[Brief description of drawings]

FIG. 1 is a flowchart for explaining a package recognition method according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an automatic sealing device used in the package recognition method of the present invention.

FIG. 3 is a diagram for explaining a method of calculating a tilt of a seal ring.

FIG. 4 is a diagram showing a frequency distribution of inclination of a seal ring.

FIG. 5 is a diagram for explaining a method of calculating a ratio of a straight line portion of a seal ring.

FIG. 6 is a plan view showing a state of packages stored in a tray.

FIG. 7 is a diagram for explaining a method of identifying the contour of the seal ring.

FIG. 8 is a diagram for explaining a sealing operation by a conventional automatic sealing device.

[Explanation of symbols]

1 ... Camera, 2 ... Image recognition device, 3 ... Jig table, 4
... Conveyance mechanism, 5 ... Joining head moving mechanism, 6 ... Welding power source,
7 ... Sequencer, 8 ... Host computer, 9 ... Keyboard.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G06T 1/00 305 G01B 11/24 G01N 21/88

Claims (2)

(57) [Claims] 1. A package recognition method in an automatic sealing device that utilizes image recognition in order to align the position of a lid that forms a lid with a polygonal package containing a circuit element, the package being imaged by a camera, The contour data of the package is extracted from the grayscale image of the captured package, the length of each side of the package is obtained from the contour data, and the straight line portion on each side is extracted from the contour data.
In the automatic sealing device characterized by calculating the ratio of the straight line portion to the obtained side length for each side and comparing the calculated ratio of the straight line portion with the determination reference value to determine whether the package is non-defective Package recognition method. 2. A package recognizing method in an automatic sealing device that utilizes image recognition for aligning a position of a polygonal package containing a circuit element and a lid as a lid thereof, the lid size indicating a size of the lid. And the recognition size for selecting the contour of the package to be recognized is preset, the package is imaged by the camera, and the lid size set when the contour data of the package is extracted from the grayscale image of the captured package Compare the recognition size with
A package recognition method in an automatic sealing device, characterized by determining whether to extract outer contour data or inner contour data of a package based on the comparison result.