JP2007313537A - Sheet working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet working machine capable of performing drilling work and drilling inspection by enhancing the accuracy in position detection in laser beam machining. <P>SOLUTION: The sheet working machine 1 is equipped with a loading section 2 for loading a honeycomb structure 21 thereon, a motor 3 for moving the loading section 2 along a guide shaft 4, an incident light illumination 11 and a diffuse illumination 12 for irradiating an end face 22 of the honeycomb structure 21, and a laser (a laser beam oscillation means) 7 for performing the laser beam machining at the machining position; and further is equipped with a mirror 16 movable on the optical axis of the laser beams, a first camera 6 as a first photographing means which is arranged outside the optical axis of the laser beams and can photograph via the mirror 16, an image of an end face of the honeycomb structure 21 irradiated with diffuse illumination while the mirror 16 is located on the optical axis, and a second camera 8 as a second photographing means capable of photographing an image of the end face 22 of the honeycomb structure 21 irradiated with the incident light illumination 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet processing machine that performs drilling on a sheet attached to a honeycomb structure.

  There is an increasing need to remove particulates and harmful substances in exhaust gas from internal combustion engines, boilers and the like from the exhaust gas in consideration of environmental impact. In particular, regulations regarding the removal of particulates (hereinafter sometimes referred to as PM) emitted from diesel engines are in a direction to be strengthened both in the US and Europe, and a collection filter (hereinafter referred to as DPF) for removing PM. A honeycomb structure is used.

  Various manufacturing methods are known for obtaining a ceramic body having a structure in which cells are alternately sealed at both end faces of the ceramic honeycomb structure. For example, a mask corresponding to each honeycomb structure is created by making a hole at a position corresponding to a predetermined cell of the sheet attached to the end face of the ceramic honeycomb structure, and the surface on which the mask is attached is used as a sealing slurry. There is a method of dipping and filling a sealing slurry into a cell from a hole formed in a mask (Patent Document 1).

Japanese Patent No. 3715174

  When manufacturing by a method of drilling holes at a position corresponding to a predetermined cell of the sheet, it is necessary to drill 14,000 holes in the Φ270 mm class, but until now, inspection has been performed by visual inspection of the operator. In other words, drilling was automated, but automated inspection after drilling was not realized. After drilling, if the product is removed from the drilling machine and inspected, the presence or absence of holes and the size of the processed holes can be detected by image processing. ) Was difficult to detect. Furthermore, it is difficult to construct a coaxial incident optical system in the drilling machine, and it is difficult to ensure illumination and inspect on the drilling machine. In recent years, the requirements for the quality of plugging have become stricter, and accordingly, the accuracy required for drilling has become stricter.

  An object of the present invention is to provide a sheet processing machine capable of improving the accuracy of position detection in laser processing and performing drilling and inspection.

In order to solve the above problems, according to the present invention,
Laser oscillation means for drilling a sheet by irradiating a laser beam to a sheet affixed to one end face of the honeycomb structure formed in a columnar shape;
Positioning means for positioning the honeycomb structure at a processing position on the optical axis of the laser beam with one end face of the honeycomb structure facing the laser oscillation means;
Diffuse illumination that illuminates the end face of the honeycomb structure disposed outside the optical axis of the laser light and positioned at the processing position with oblique light;
A movable mirror on the optical axis of the laser beam;
A first imaging means arranged outside the optical axis of the laser beam and capable of imaging the end face of the honeycomb structure irradiated with diffuse illumination through the mirror in a state where the mirror is positioned on the optical axis;
Epi-illumination illumination that illuminates the end face of the honeycomb structure disposed outside the optical axis of the laser light and positioned at the processing position with oblique light;
A second photographing means capable of photographing the end face of the honeycomb structure irradiated with the epi-illumination,
With the mirror disposed on the optical axis, the reflected light from the end face of the diffuse illumination is reflected by the mirror, the first image is taken by the first photographing means, the first image is processed, and the honeycomb structure After recognizing the body cell position,
Drilling is performed by laser oscillation means with the mirror placed outside the optical axis, and then
There is provided a sheet processing machine that irradiates the end face with light emitted from the incident illumination, takes a second image of the end face with a second photographing means, and performs image processing on the second image to perform a hole inspection.

  In the sheet processing machine of the present invention, a second image before punching is preliminarily photographed by the second photographing means, and the second image before drilling is compared with the second image after drilling to perform a drilling inspection. A configuration can be employed.

  It can comprise so that a 2nd imaging | photography means may be arrange | positioned in the reflection direction by the end surface of epi-illumination. The positioning means arranges the honeycomb structure so that the normal direction of the end face of the honeycomb structure coincides with the optical axis of the laser beam.

  In the above configuration, the dark color image portion of the first image can be recognized as the cell position. Further, the dark image of the second image can be recognized as a hole formed by drilling with a laser beam. Furthermore, the light branching unit can be configured by a triangular prism or a half mirror.

  In the sheet processing machine of the present invention, the honeycomb structure is positioned at the processing position by the positioning unit, the mirror is disposed on the optical axis of the laser oscillation unit, and the end surface is irradiated with the oblique light by the diffuse illumination and the first imaging unit The first image of the end face can be taken by. By irradiating the end surface with oblique light by diffuse illumination, it is possible to photograph the inside of the cell of the honeycomb structure as a dark color image portion and the partition of the cell as a light color image portion.

  Then, by processing the first image, after recognizing the cell position of the honeycomb structure from the dark color image portion and the light color image portion, punching processing of the sheet attached to the end surface based on the recognized cell position Can be performed by laser oscillation means.

  Furthermore, the end face can be irradiated with light emitted from the epi-illumination, and the second image of the end face can be taken by the second photographing means by the reflected light. By doing so, the contrast of the holes other than the holes becomes clear, and photographing can be performed with high accuracy. Then, the second image is image-processed, the dark image portion is recognized as a hole formed by drilling, and it is determined whether or not the hole is formed at a predetermined position with respect to the cell position, It can be determined whether or not processing by drilling has been performed normally. Furthermore, since the first image for cell position recognition, the drilling process, and the second image for the hole inspection are performed with the honeycomb structure fixed at the same position, no positional deviation occurs. Further, since the honeycomb structure is not moved, the time required for processing can be shortened.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following embodiments, and changes, modifications, and improvements can be added without departing from the scope of the invention. The “honeycomb structure” referred to in this specification includes not only a fired body but also an unfired dried body (one obtained by drying only the extruded body of clay and not yet fired).

  FIG. 1 shows a sheet processing machine 1 according to an embodiment of the present invention. The sheet processing machine 1 includes a placement portion 2 for placing the honeycomb structure 21, a motor 3 for moving the placement portion 2 along the guide shaft 4, and an epi-illumination for irradiating the end face 22 of the honeycomb structure 21. And a laser (laser oscillation means) 7 for performing laser processing on the processing position. Further, a mirror 16 movable on the optical axis of the laser beam and an end face of the honeycomb structure 21 irradiated with diffuse illumination with the mirror 16 positioned on the optical axis are mirrored. A first camera 6 that is a first photographing means that can be photographed via the first camera 16, and a second camera 8 that is a second photographing means that is capable of photographing the end face 22 of the honeycomb structure 21 irradiated with the incident illumination 11. Prepare.

  The placement portion 2 is configured to place the honeycomb structure 21 that is not plugged and to be moved to a processing position by the motor 3 along the guide shaft 4. The honeycomb structure 21 can be positioned at the processing position by the mounting portion 2. That is, the mounting portion 2, the guide shaft 4, and the motor 3 are positioning means for positioning the honeycomb structure 21 at the processing position with one end face 22 of the honeycomb structure 21 formed in a columnar shape in a predetermined direction. Configure.

  The laser 7 that is a laser oscillation means is disposed on the axis of the honeycomb structure 21 positioned at the processing position so that the optical axis of the laser light is along the axis, and is affixed to the end face 22 of the honeycomb structure 21. The sheet 24 is punched by irradiating the sheet 24 with laser light.

As the laser 7 used in the sheet processing machine 1 of the present embodiment, for example, a YAG laser, a CO ₂ laser, or a UV laser can be suitably used. By using such a laser 7, for example, a hole can be formed in the sheet 24 attached to the end face of the honeycomb structure 21. Moreover, since this laser 7 can use suitably the commercially available laser marker, for example, the laser marker of a galvanometer mirror scanning system, etc., the cost reduction of the sheet processing machine 1 is realizable. In order to make the laser processed surface constant, it is preferable to provide a mechanism for detecting and adjusting the height direction of the upper end surface 22 of the honeycomb structure 21 in the mounting portion 2 of the positioning means.

  The diffuse illumination 12 irradiates the end surface of the honeycomb structure 21 positioned at the processing position with oblique light. The diffuse illumination includes, for example, an LED serving as a light source and a light diffuser that diffuses light from the LDE. Alternatively, a lamp light source such as halogen or mercury, or an inexpensive fluorescent lamp with stable brightness can be used as the diffuse illumination.

  The epi-illumination illumination 11 is configured to include, for example, an LED serving as a light source, and is disposed outside the optical axis of the laser beam and irradiates the end surface 22 of the honeycomb structure 21 positioned at the processing position with oblique light. Further, as the first camera 6 and the second camera 8 constituting the photographing means, a CCD camera can be preferably used.

  In order to punch the sheet 24 by irradiating the sheet 24 affixed to the end face 22 of the honeycomb structure 21 with laser light by the sheet processing machine 1, first, a ceramic honeycomb structure 21 ( A ceramic honeycomb structure before firing) is prepared. As the ceramic honeycomb structure 21, a conventionally known ceramic honeycomb structure made of cordierite can be preferably used. The ceramic honeycomb structure 21 can be produced in the same manner as before by extruding the raw material from the die after mixing.

  As shown in FIG. 2A, a sheet 24 having substantially the same shape as the end face 22 of the ceramic honeycomb structure 21 is prepared, and as shown in FIG. A sheet 24 is affixed to the end face 22. A commercially available adhesive sheet can be used as the sheet 24. Then, as shown in FIG. 1, the honeycomb structure 21 is placed on the placement portion 2 of the sheet processing machine 1 and drilling is performed by the laser 7.

  Next, a laser processing process is demonstrated using the flowchart of FIGS. FIG. 3 shows an overall process of the laser processing process. The sheet processing machine 1 performs a cell position confirmation step of the unplugged honeycomb structure 21 placed on the placement portion 2 (S1), and based on the result, performs a punching step, A hole is formed in (S2). Subsequently, a hole inspection process is performed, and it is determined whether or not the hole is formed at a predetermined position with respect to the cell position, and it is determined whether or not the processing by the hole drilling is normally performed (S3). ). Next, details of each of these steps will be described with reference to FIGS.

  First, details of the cell position confirmation step of S1 will be described with reference to FIG. The sheet processing machine 1 moves the honeycomb structure 21 mounted on the mounting unit 2 to the processing position by the motor 3 (S11: see FIG. 1). Next, the mirror 16 is set to the first position (S12), and the diffuse illumination 12 is turned on (S13). And the 1st image of the end surface 22 of the honeycomb structure 21 irradiated with the diffuse illumination 12 is image | photographed with the 1st camera 6 via the mirror 16 (S14).

  FIG. 6 schematically shows an example of the first image of the end face 22 taken by diffuse illumination. The diffused illumination 12 allows the end face 22 to be photographed through the sheet 24. The end face 22 is photographed with the partition wall portion 22a as a bright color image portion and the inside of the cell 22b as a dark color image portion. That is, in S15 of FIG. 4, the sheet processing machine 1 can recognize the dark color image portion as in the cell 22b.

  Further, in S14, the second image before photographing the second image is photographed by the second camera 8 simultaneously with the photographing of the first image. A cell position for drilling inspection is calculated from the second image before drilling, and a drilling pattern is determined based on these information.

  Subsequently, in the drilling step of S2, with the mirror 16 retracted to the second position outside the optical axis, the hole 25 is formed at a position corresponding to the predetermined cell 22b of the sheet 24 based on the image information described above. Form.

  Next, details of the drilling inspection process in S3 will be described with reference to FIG. The sheet processing machine 1 turns on the epi-illumination illumination 11 (S31) and takes a second image with the second camera 8 (S32).

  FIG. 7 schematically shows an example of the second image of the end face 22 taken by epi-illumination. The epi-illumination 11 can pass through the sheet 24 and photograph the end face 22. That is, since the second camera 8 is arranged in the direction of reflection by the light emitting sheet 24 of the epi-illumination illumination 11 irradiated on the end face 22, the outer edge of the hole 25 can be clearly photographed. The sheet 24 is photographed as a light color image portion, and the end face 22 is photographed as a light color image portion whose partition wall portion 22 a is slightly darker than the sheet 24. Further, since the hole 25 formed in the sheet 24 is photographed through the cell 22b on the rear side, the hole 25 is photographed as a dark color image portion. That is, in S33, the sheet processing machine 1 can detect the position and area of the hole using the dark color image portion as the hole 25.

  Returning to FIG. 5, after performing image analysis in S <b> 33, the sheet processing machine 1 determines whether or not a predetermined cell is drilled, the size of the hole, and the positional deviation are equal to or less than a predetermined reference ( S34). If it is less than the predetermined standard (S34: YES), the honeycomb structure 21 is discharged as a defective product (S35). On the other hand, when it is determined that the predetermined standard is satisfied (S34: NO), the honeycomb structure 21 is recovered as a non-defective product (S36), and the process proceeds to the next step.

  When the drilling inspection step (S3) in FIG. 3 is completed, it is determined whether the processing has been completed for all the blocks (S4). If it is determined that the process has not been completed, the process moves to the adjacent block as shown in FIG. 8 (S5), and the same process is performed. At this time, the sheet processing machine 1 detects the processed hole 25 that is visible for the camera area slightly larger than the processing area by the epi-illumination, and identifies the hole processed cell. Then, the low-angle illumination (diffuse illumination 12) is turned on to detect the cell position, and the drilling pattern is determined based on the processed cell. And the above-mentioned drilling process is performed similarly.

  When all the blocks are finished (S4: YES), the laser processing process is finished and the process proceeds to the plugging process. A ceramic honeycomb structure in which the end face 22 to which the sheet 24 with holes 25 is affixed is immersed in slurry in a container to plug the honeycomb structure 21 and the predetermined cells 22b on both end faces are filled with the slurry 26. A body 21 is obtained. Finally, a ceramic having a structure in which the cells 22b are alternately sealed at both end surfaces of the target ceramic honeycomb structure 21 by firing the ceramic honeycomb structure 21 in which slurry is filled in predetermined cells 22b at both end surfaces. You can get a body. Such a ceramic body is mainly used as a DPF (diesel particulate filter) used for removing graphite and the like of a diesel engine.

  As described above, by photographing the first image using the diffuse illumination 12, the cell position can be clearly photographed. Moreover, the hole 25 can be clearly image | photographed by arrange | positioning and image | photographing the 2nd camera 8 in the reflection direction of the reflected light reflected by the end surface 22 using the epi-illumination 11. Therefore, the sheet processing machine 1 can perform the drilling process with high accuracy and can perform the drilling inspection automatically by image processing. In the present invention, the first image for cell position recognition, the drilling process, and the second image for the hole inspection are performed with the honeycomb structure fixed at the same position. Does not occur. In addition, since the honeycomb structure is not moved, the time required for processing can be shortened.

  INDUSTRIAL APPLICABILITY The present invention can be used as a sheet processing machine that performs laser processing at a predetermined position using a laser, and in particular, when manufacturing a honeycomb structure used as a DPF used for removing graphite or the like of a diesel engine. In addition, it can be used as a sheet processing machine for drilling a sheet attached to a honeycomb structure.

It is a figure which shows the sheet processing machine as one Embodiment of this invention. It is a figure which shows sticking of the sheet | seat to a honeycomb structure. It is a figure which shows the honeycomb structure to which the sheet | seat was affixed. It is a flowchart which shows a laser processing process. It is a flowchart which shows the detail of a cell position confirmation process. It is a flowchart which shows the detail of a drilling test process. It is a schematic diagram of the 1st image by diffuse illumination. It is a schematic diagram of the 2nd image by epi-illumination. It is a figure explaining a block.

Explanation of symbols

1: sheet processing machine, 2: placement unit, 3: motor, 4: guide shaft, 6: first camera, 7: laser, 8: second camera, 11: shooting illumination, 12: diffuse illumination, 16: Mirror, 21: honeycomb structure, 22: end face, 22a: partition wall, 22b: cell, 24: sheet, 25: hole.

Claims (7)

Laser oscillation means for performing drilling of the sheet by irradiating a laser beam to the sheet attached to one end face of the honeycomb structure formed in a columnar shape;
Positioning means for positioning the honeycomb structure at a processing position on the optical axis of the laser beam with one end face of the honeycomb structure facing the laser oscillation means;
Diffuse illumination for irradiating the end face of the honeycomb structure disposed off the optical axis of the laser light and positioned at the processing position with oblique light;
A mirror movable on the optical axis of the laser beam;
The first end face of the honeycomb structure that is disposed outside the optical axis of the laser light and is irradiated with the diffuse illumination in a state where the mirror is positioned on the optical axis can be photographed through the mirror. Photographing means;
Epi-illumination for irradiating the end face of the honeycomb structure, which is disposed outside the optical axis of the laser light and positioned at the processing position, with oblique light;
A second photographing means capable of photographing the end face of the honeycomb structure irradiated with the epi-illumination,
With the mirror disposed on the optical axis, the reflected light from the end face of the diffuse illumination is reflected by the mirror and the first image is taken by the first photographing means, and the first image is taken as an image. After processing and recognizing the cell position of the honeycomb structure,
The drilling is performed by the laser oscillation means in a state where the mirror is disposed outside the optical axis, and then
A sheet processing machine that irradiates the end face with light emitted from the epi-illumination, takes a second image of the end face with the second photographing means, and performs image processing on the second image to perform the punching inspection.   2. The second image before drilling is preliminarily imaged by the second imaging unit, and the second image before drilling is compared with the second image after drilling to perform the drilling inspection. The sheet processing machine described in 1.   The sheet processing machine according to claim 1, wherein the second photographing unit is arranged in a direction reflected by the end surface of the incident illumination.   The sheet according to any one of claims 1 to 3, wherein the positioning unit arranges the honeycomb structure so that a normal direction of the end face of the honeycomb structure coincides with the optical axis of the laser beam. Processing machine.   The sheet processing machine according to any one of claims 1 to 4, wherein the first photographing unit is arranged with a photographing direction facing the mirror.   The sheet processing machine according to any one of claims 1 to 5, wherein a dark color image portion of the first image is recognized as the cell position.   The sheet processing machine according to any one of claims 1 to 6, wherein a dark color image of the second image is recognized as a hole formed by the drilling process using the laser beam.

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