JPH076378B2 - Diesel particulate filter end seal inspection and correction device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DPF end seal inspection / correction device for automatically determining and correcting the end seal of a diesel particulate filter (hereinafter referred to as DPF). is there.

[0002]

2. Description of the Related Art Conventionally, a DPF has been used for collecting fine particles in exhaust gas discharged from a diesel vehicle and discharging clean exhaust gas to the outside. This DPF is made of porous cordierite and has a columnar shape of a honeycomb structure in which a large number of through holes are divided by cell walls in the gas flow direction. As shown in the end structure in FIG. 6, the end portions are alternately plugged for each cell so that one of the through holes 32 of the DPF 31 serves as the plug portion 33.

In order to manufacture the DPF having the above-mentioned structure, a honeycomb structure filter having all through-holes is extruded and then fired to obtain a mask, and then a mask having holes at the portions corresponding to the plugging portions is used. Position and fix it on the end of the filter, push the cordierite slurry that is the same material as the filter through the mask, and after finishing pushing the same slurry on both ends, remove the mask on both ends. It is fired again to obtain DPF.

[0004]

In the DPF obtained by the method described above, it is necessary that the plugging portion at the end portion completely closes the opening portion, and the through hole other than the plugging portion is completely opened. However, since the cells of the honeycomb structure are not all the same size, it is difficult to position the mask, and there are usually holes in the plugging part,
There was a problem that the penetration part was blocked. In order to correct this point, conventionally, a skilled worker visually inspected, and if it was empirically determined that the through hole part was blocked, it was necessary to manually open the hole with a correction needle, which is troublesome. It took a long time and there was a problem that the automation line could not be achieved.

The object of the present invention is to solve the above problems,
A DPF capable of automatically inspecting a plugged state of an end portion of the DPF and automatically correcting a portion determined to be defective.
The present invention seeks to provide an end-sealing inspection / correction device.

[0006]

SUMMARY OF THE INVENTION A DPF end seal inspection / correction device of the present invention includes a base and a diesel particulate filter (hereinafter referred to as DPF) provided on the base in the X direction and An XY table for moving in the Y direction, a support arm erected on the base, and an imaging device fixed to the support arm for imaging the end portion of the DPF placed on the XY table, An end sealing correction device that is fixed to a support arm through a vertical drive device and that punches an end of the DPF placed on the XY table, and an end image of a work imaged by the imaging device. On the basis of the above, an image processing device for determining the plugging of the end portion of the work, and a drive control device for supplying correction information of the edge sealing to the edge sealing correction device based on the result of the determination are characterized. To do.

[0007]

In the above-mentioned structure, the image processing is performed on the image of the end of the DPF captured by the image pickup device to automatically determine the plugging state, and based on the result of the determination, the image of the end of the end is detected. Since the defective cell of the end plugging can be automatically corrected by the sealing correction device, all the operations can be automated, the labor and time can be greatly reduced, and it can be incorporated into an automated line for use. Further, as a preferable mode in the image processing apparatus, when the end image is divided into the effective area and the ineffective area and then the plugged state is determined for each area, the cells at the end are not uniform. Even if it is distorted, the number of judgment defects can be reduced. Furthermore, as a preferable mode in the end portion sealing correction device,
When the correction device for automatic alignment of the correction needle is provided, the defective cell at the end can be corrected more preferably.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing the construction of an example of a DPF end seal inspection / correction device of the present invention. In FIG. 1, 1 is a pedestal, 2 is an XY table provided on the pedestal 1, on which a DPF 3 as a work can be placed with its end facing upward,
Reference numerals 4 and 5 denote an X-direction driving device and a Y-direction driving device for the XY table 2, 6 denotes a supporting arm provided on the base 1, 7 denotes a DPF mounted on the XY table 2, which is fixed to the supporting arm 6.
An image pickup device such as a CCD camera for picking up an image of the end of 3;
8 is an X fixed to the support arm 6 via a vertical drive device 9,
An edge sealing correction device for making a hole in the end of the DPF 3 placed on the Y table 2 and 10 is a D imaged by the imaging device 7.
An image processing device that determines the end-sealing state of the DPF 3 based on the end image of the PF 3, and 11 supplies the end-sealing correction information to the end-sealing correction device 8 based on the determination information in the image processing device 10. In addition, the drive control device supplies position information to be corrected to the X-direction drive device 4 and the Y-direction drive device 5.

In the above-described DPF end portion sealing inspection / correction device, first, the DPF 3 to be inspected is placed at a predetermined position on the XY table 2, and the X-direction driving device 4 and the Y-direction driving are performed while imaging by the imaging device 7. The device 5 is driven and positioned at a position where an image is to be captured. Next, the image processing apparatus 1
At 0, the plugged state of the edge is determined from the captured image, and the position of the defective cell determined to be a defect in the image is stored in the memory. Next, based on the stored defective cell position information, the X-direction drive device 4, the Y-direction drive device 5, and the vertical drive device 9 of the end-portion sealing correction device 8 are controlled to control the end-portion sealing correction device 8. All the defective cells are corrected by.
Usually, since the diameter of the DPF 3 is large and the cells forming the honeycomb structure are small, the end portion is divided into a plurality of images for processing. In that case, the above operation is repeated for the number of divided images so that one end portion of the DPF 3 is The inspection and correction are completed, and this is also performed on the other end, thereby completing all the inspection and correction work.

An example of a method of extracting a defective cell in the image processing apparatus 10 of the DPF end plugging inspection / correction apparatus of the present invention will be described. First, an image of a size that allows each cell to be recognized on the image is taken, The captured image is binarized. At this time, since the cells of the honeycomb structure at the end of the DPF are all manufactured at the same pitch, the grid-like cells obtained according to the magnification on the binarized image are overlapped and the upper left part of the cell is plugged. It is necessary to take an image so that the parts fit in. Then, when the ratio of the through holes other than the plugged portion in each cell is less than 78%, for example, the defective cell is determined to determine the defective cell. The above-described determination method can also be used to appropriately perform the determination of the defective cell, but since the upper left cell is used as a reference, for example, if the cell pattern is disturbed, only a part of the through hole is within the cell. There is also a case where a normal cell that does not exist in the memory cell is erroneously determined as a defective cell. An example of a more preferable defective cell extraction method will be described below.

FIG. 2 is a diagram for explaining another example of the method of extracting defective cells in the image processing apparatus 10 of the DPF end sealing inspection / correction apparatus of the present invention. FIG. 2 schematically shows a part of the upper left corner of the binarized image, in which a group of pixels of "1" drawn in black corresponds to a through hole, and a pixel of "0" drawn in white. Each of the groups represents the plugging part. In addition, A to E indicate windows in an image used for extracting a defective cell. From experience, the window E corresponds to a 1/4 region of the entire screen, and the windows A and B correspond to three cells on the image in width. An area having the same size and the same length as the area E, the windows C and D have a width of 1.5 on the image.
Regions having the same size as the cell and the same length as the region E are shown. Note that, in FIG. 2, the opening portion drawn in black is drawn in a circular shape for convenience of description, but it is actually a honeycomb shape close to a square.

In FIG. 2, first, the center of gravity of a block of black pixels in the area A is found, and the order of the found barycentric coordinates is ascending order in the Y direction for each block. Similarly, the black pixel clusters in the area B are ranked in the X direction. Next, Y set in advance so that the Y-direction barycentric coordinate of the block having the first rank in the area A becomes the center in the Y-direction.
An area C having a width slightly larger than one cell in the direction and a width of several cells in the X direction is moved. Then, the barycentric coordinates in the Y direction of the block of black pixels in the area C are averaged. A threshold line in the Y direction is determined from the actual pitch between the cells centering on the obtained average value of the barycentric coordinates in the Y direction.
Similarly, the area D is moved into the area B, and the threshold line in the X direction is determined from the average value of the barycentric coordinates in the X direction and the cell pitch. By the above-described work, grid-like threshold lines corresponding to cells are provided over the entire image.

Next, a line E is drawn in the first cell surrounded by the threshold line at the upper left end, as shown in FIG. 2, and it is determined whether or not a black pixel exists on the line F by the threshold line. It is determined whether the first cell surrounded is an effective area having a through hole or an invalid area which is a plugging portion. 3A shows the case where the first cell is the effective area, and FIG. 3B shows the case where the first cell is the invalid area. Due to the characteristics of the product, all patterns can be recognized by determining whether the first cell surrounded by the threshold line is the valid area or the invalid area. Then, the black lumps in the area E of FIG. 2 are extracted, and all the barycentric coordinates of the black lumps in the extracted cells are calculated and obtained. Then, it is determined whether or not there is a barycentric coordinate obtained by calculation in the effective area, and if there is not, the data is output as a defective cell. If so, the data is output in the same manner and stored in the memory together with the coordinate position. During the above work, all cells in the boundary areas in areas A to E are invalid.

FIG. 4 is a diagram showing the configuration of an example of the end sealing correction device 8 of the DPF end sealing inspection correction device of the present invention. The end portion sealing / correcting device 8 shown in FIG. 4 is used for making a hole in a defective cell having a so-called incomplete opening in which a cell that should be a through hole is closed. In FIG. 4, 21 is a correction needle whose tip is tapered by, for example, 60 degrees, and 22 is a position for automatically correcting the position of the correction needle 21 even if the correction needle 21 is deviated from the position of the incomplete hole portion. It is a correction mechanism. The position correction mechanism 22 is a DPF.
Disk-shaped upper plate 23 connected to the vertically movable drive device 9 attached to the support arm of the end-sealing inspection correction device
And a plurality of elastic members 25 are provided between the disk-shaped lower plate 24 and the correction needle 21.
Therefore, in this end portion sealing and correcting device 8, as shown in an example in FIG. 5, even if the tip of the correcting needle 21 and the center of the through hole do not coincide with each other, first, the tip wall of the correcting needle 21 is tapered to the cell wall. After the correction needle 21 comes into contact with and slips, the elastic member 25 of the position correction mechanism 22 is deformed and the correction needle 21 is automatically guided into the through hole, so that good correction can be performed.

[0015]

As is apparent from the above description, according to the present invention, image processing is performed on the image of the end of the DPF captured by the image pickup device to automatically determine the plugged state. Then, based on the judgment result, the defective cell of the end plugging can be automatically corrected by the end plugging correction device, so that all the work can be automated, and the labor and time can be greatly shortened, and the automation line It can be used by being incorporated into.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an example of a DPF end sealing inspection correcting device of the present invention.

FIG. 2 is a diagram for explaining a method of extracting a defective cell in the image processing device of the DPF end portion sealing inspection and correction device of the present invention.

FIG. 3 is a diagram for explaining an effective area and an invalid area in the defective cell extraction of the present invention.

FIG. 4 is a diagram showing a configuration of an example of an end portion sealing correction device of the DPF end portion sealing inspection correction device of the present invention.

FIG. 5 is a diagram for explaining a method for correcting the position of the end portion sealing correction device of the present invention.

FIG. 6 is a diagram showing an example of an end configuration of a DPF.

[Explanation of reference numerals] 1 base 2 XY table 3 DPF 4 X-direction drive device 5 Y-direction drive device 6 support arm 7 imaging device 8 edge sealing correction device 9 vertical drive device 10 image processing device 11 drive control device

Claims (3)

[Claims] 1. A base, an XY table provided on the base for moving a diesel particulate filter (hereinafter, referred to as DPF) in the X direction and the Y direction, and erected on the base. Support arm and fixed to the support arm,
An image pickup device for picking up an image of the end portion of the DPF placed on the XY table, and a hole for the end portion of the DPF placed on the XY table, which is fixed to the support arm via a vertical drive device. An edge sealing correction device to perform, an image processing device that determines the sealing of the edge of the work based on the edge image of the work captured by the imaging device, and the edge sealing correction device based on the determination result. An end plugging inspection correction device for a diesel particulate filter, comprising: a drive control device that supplies correction information of the end plugging to the end. 2. The image processing apparatus binarizes an edge image of a DPF captured by the image capturing apparatus, and distinguishes the edge of the DPF into an effective area to be opened on the image and an invalid area to be sealed. The device for inspecting and correcting an end portion of a diesel particulate filter according to claim 1, wherein the open area ratio in the effective area is measured and the defective cell is determined based on the measured open area ratio. 3. A correction needle having a taper tip for correcting the end-sealing correction device by piercing an incomplete opening at the end of the DPF, and the correction needle has an incomplete opening. 3. An end plugging inspection correction device for a diesel particulate filter according to claim 1 or 2, further comprising a position correction mechanism that automatically corrects the position of the correction needle even if the position is deviated from the position.