JPH1049677A - Package recognizing method for automatic sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately judge whether a package is normal or not at the time of image recognition by calculating and comparing the rate of straight-line parts of outline data on the package with a criterion, and deciding whether the package is normal. SOLUTION: An image recognizing device 2 calculates the tilt and the center of gravity of an extracted seal ring in a horizontal plane from the outline data on the seal ring. The respective sides of the seal ring are determined by a method of least square from data which are present within a certain range roughly centering on the sides. Then, the image recognizing device 2 finds the rates of straight line parts of the outline data by the determined sides. Then the image recognizing device 2 compares the calculated rates of the straight line parts with the criterion inputted previously from a keyboard 9 to judge whether the package is normal or not. At this time, when a straight-line part is smaller than the criterion, it is decided that the package is a defective. Then this defective is automatically taken out by a carrying mechanism 4.

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 (lid) to a container (package) of a circuit element such as an IC, a transistor, a crystal unit, etc. The present invention relates to a package recognition method using image recognition for matching.

[0002]

2. Description of the Related Art Sealing of circuit elements such as ICs, transistors, and crystal units is performed as a final manufacturing process after these circuit elements are housed in a package and wiring and test adjustment operations are performed. Examples of the sealing method include resin sealing and airtight sealing. The hermetic 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 hermetic sealing method, since there is no intrusion of impurities such as moisture and the element does not come into direct contact with the sealing material, the effect of thermal stress is small and high sealing reliability can be obtained as compared with resin sealing. Can be.

There is an automatic sealing device that automatically welds 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 view for explaining a sealing operation by a conventional automatic sealing device. As shown in FIG. 8A, a seal ring 31 made of a pre-gold plated Kovar material is soldered around a sealing portion (a portion in which the element is stored) of the package 30. Then, an image is captured by an image recognition device (not shown), the position of the seal ring 31 is calculated, and the lid 32 made of a metal plate (usually a nickel-plated Kovar material) and the seal ring 31 are positioned (FIG. 8B )).

Subsequently, a pair of roller electrodes 33 is applied to the opposing edges of the lid 32 to apply an appropriate pressing force. When a current flows between the electrodes in this state, the contact portion (the electrode 33 and the lid 32) generates heat due to Joule heat, and the heat is transmitted to the contact portion between the lid 32 and the seal ring 31, so that the lid 32 and the seal ring 31 Are melt-bonded to each other. Furthermore, by rolling the roller electrode 33 along the edge of the lid 32 while applying a current, the opposite sides of the lid 32 can be seam-bonded at the same time. Since the package is usually rectangular,
After joining the X sides as shown in FIG. 8C, the joining of the Y sides is similarly performed as shown in FIG. Thus, the lid can be welded to the package.

By the way, in such an automatic sealing apparatus, the seal ring 31 and the lid 32 are used by using image recognition for taking in the image of the seal ring 31 and calculating the position.
Is positioned. At this time, if no package is placed on the tray for transporting the package, or if the package is defective, welding must not be performed. However, the package is determined to be defective when recognition failure occurs due to disturbance (effect of vibration of the apparatus itself or influence of external light) or when the contour of the extracted seal ring is discontinuous (sealing ring). (When the contour is interrupted by a scratch or the like crossing). If the seal ring has scratches or dirt, the extracted contour will undulate, but the package will not be determined to be defective unless the contour is discontinuous.

Further, the above-mentioned tray is provided with a recess having a shape similar to the outer shape of the package, and the package is accommodated in the recess. Sometimes it was judged. Also, the recognition target is usually the outer contour of the seal ring, but image recognition may not be stable due to the above-described disturbance and the shape of the package. The software was modified so that it could be recognized.

[0007]

As described above, in the conventional automatic sealing apparatus, since there is no settable threshold value for judging a non-defective product or a defective product, there is no set threshold value. Therefore, the threshold value cannot be adjusted so that an appropriate determination is made, and an inappropriate determination or erroneous recognition occurs. Further, in order to switch between the recognition of the outer contour of the package and the recognition of the inner contour,
A software expert had to modify it, and once set, there was the problem that all types of packages would be measured either way. The present invention
A first object of the present invention is to provide a method for recognizing a package capable of appropriately determining whether a product is good or bad during image recognition. It is a second object of the present invention to provide a package recognition method capable of easily switching the outline of a package to be recognized.

[0008]

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

According to a second aspect of the present invention, a lid size indicating the size of the lid and a recognition size for selecting an outline of a package to be recognized are set in advance, and the package is imaged with a camera. When extracting package outline data from the shaded image of the package, compare the set lid size with the recognition size,
Based on the result of the comparison, 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 as the recognition target.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

1. Embodiment 1. FIG. 1 is a flowchart for explaining a package recognition method according to a first embodiment of the present invention, and FIG. 2 is a block diagram of an automatic sealing device used in the 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 transports the lid directly above the package. The joining head moving mechanism 5 lowers the joining head (not shown) onto the package, and the welding power source 6 supplies a current to the roller electrodes of the joining head. And 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 transport mechanism 4 transports the tray on which the package is placed to the jig table 3, and the camera 1
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 the grayscale image. And
The contour of the seal ring is extracted by deleting data of inappropriate size according to the seal ring size indicating the outer size of the seal ring set in advance (step 10).
2).

Subsequently, 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 of calculating the inclination of the seal ring.
White circles in the figure are extracted outline data (dots).
The inclination of the seal ring in the θ direction is obtained as follows.

First, the frequency of inclination of each line connecting the contour data is obtained 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 value of the inclination of each region with high frequency in FIG. Get a rough idea of the location.

Next, the sides A to D of the seal ring are determined by the least squares method from data existing within a certain range α centered on the approximate side. Thus, the inclination of the seal ring in the XY plane is obtained. Further, the center of gravity O of the seal ring is obtained from the determined sides A to D. Thus, the position of the seal ring can be determined.

Next, the image recognition device 2 obtains the ratio 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 the straight line portion. In FIG. 5B, only one side A of the seal ring is enlarged. First, the image recognition device 2 calculates the total length including the curved corners for each of the sides A to D, and sets them as LA, LB, LC, and LD, respectively (FIG. 5A).

Subsequently, as shown in FIG. 5B, a fixed range β is set in the width direction with the side A as a center. The straight line portion on the side A including the corner portion is a portion constituted by data continuously existing for a predetermined length (for example, 3 dots) or more within this range β. Therefore, the portion E in FIG. 5B is not included in the straight line portion. Thus, the length JA of the straight line portion is obtained. Then, the ratio (JA / LA) of the length JA of the linear 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 determines whether the package is non-defective by comparing the determination reference value input from the keyboard 9 in advance with the calculated ratio of the linear portion (step 105). At this time, if the ratio of the linear portion is smaller than the determination reference value, it is determined to be defective. Then, the defective product is automatically taken out by the transport mechanism 4 (step 106).

If the ratio of the linear portion is determined to be non-defective when the ratio is equal to or greater than the determination reference value, the jig table 3 is controlled by the sequencer 7 based on the determined seal ring position.
It moves in the Y direction and rotates in the θ direction to adjust the positions of the seal ring and the lid (step 107). Then, the joining head moving mechanism 5 lowers the joining head onto the package, and the welding power source 6 supplies a current to the roller electrodes of the joining head, whereby the lid is welded to the package (Step 108).

As described above, in this 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, imaging conditions, and the like. In addition, the undulation of the contour caused by the scratch or dirt on the seal ring is excluded from the straight line portion, and the ratio of the straight line portion is below the determination reference value. Can be detected as defective.

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. However, the recess 24 for taking out the package reduces the proportion of the linear portion. Lower than the package. Therefore, by properly setting the determination reference value, the depression 23 of the tray is not erroneously recognized as a package.

Embodiment 2 Also in the present embodiment, the configuration of the automatic sealing device is the same as in FIG. 2, and the package recognition method is almost the same as 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, it is automatically switched whether to extract the outer contour or the inner contour. .

For this switching, an operator who uses the automatic sealing device operates the keyboard 9 to input a lid size indicating the length and width (X, Y) of the lid and a 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 the recognition size.

If the recognition of the package 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 the recognition size. Accordingly, in step 102 of FIG. 1, the image recognition device 2 compares the input lid size with the recognition size, and if the recognition size is equal to or larger than the lid size, extracts the outer contour of the seal ring, and If it is smaller than the lid size, the contour inside the seal ring is extracted.

From the viewpoint of 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 group of dots, it is displayed here as a line.

When the package is imaged, the seal ring 2
The portion 5 has a high brightness level, and the inside and surroundings have a low brightness level. Accordingly, when the binary image data shown in FIG. 7 is scanned 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”, the contour on the inside of the seal ring is obtained, and when the image data changes from “bright” to “dark”, the contour on the outside of the seal ring is obtained. Thus, the image recognition device 2 can select the outer contour or the inner contour of the seal ring. The operation after step 103 is the same as in 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.
By setting an appropriate value for the determination reference value, it is possible to make an appropriate determination according to the type of package, imaging conditions, and the like, and the tray is not erroneously recognized as a package. In addition, since the undulation of the contour caused by the flaw or dirt on the seal ring is removed from the linear portion, even if the contour has continuity, it can be detected as a defective product.

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

[Brief description of the 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 the inclination 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 linear portion of a seal ring.

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

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

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Camera, 2 ... Image recognition device, 3 ... Jig table, 4
... conveying mechanism, 5 ... joint head moving mechanism, 6 ... welding power supply,
7 ... sequencer, 8 ... host computer, 9 ... keyboard.

Claims (2)

[Claims] 1. A package recognition method in an automatic sealing device using image recognition for aligning a polygonal package containing circuit elements with a lid serving as a lid of the package. Extracting the contour data of the package from the captured grayscale image of the package, determining the length of each side of the package from the contour data, extracting a straight line portion on each side from the contour data,
The automatic sealing device is characterized in that the ratio of the straight line portion to the determined side length is calculated for each side, and the calculated ratio of the straight line portion is compared with a determination reference value to determine whether the package is non-defective. Package recognition method. 2. A method for recognizing a package in an automatic sealing device using image recognition for aligning a polygonal package accommodating a circuit element and a lid serving as a lid thereof, wherein the lid size indicates the size of the lid. And a recognition size for selecting a contour of a package to be recognized is set in advance, and the package is taken by a camera, and when the contour data of the package is extracted from a captured grayscale image of the package, a set lid size is set. And the recognition size,
A method for recognizing a package in an automatic sealing device, comprising determining whether to extract outline data outside or inside of a package based on a result of the comparison.