JP2004205325A - Inspecting apparatus of sheet integration body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for identifying a direction fail sheet having a direction different from other sheets in laminated sheets at low costs. <P>SOLUTION: A sheet direction fail apparatus 1 comprises a camera 2; a camera shift mechanism 3; a system controller 4; and an illuminator 5. The camera 2 images a cutout 12 of a sheet 11 in the state of a sheet integration body 10 on a working bench 6 from the X-axis direction. The camera shift mechanism 3 moves the camera 2 along the Z-axis direction. The camera 2 that is moved by the camera shift mechanism 3 and images the sheet in the entire layer of the sheet integration body 10 transmits image data to a system controller 4. The system controller 4 performs thin-line removal processing and binarization processing to the image data and judges that the sheet whose cutout 12 is not imaged is the direction fail sheet. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for discriminating a direction defective sheet having a direction different from that of other sheets in a sheet stack in which a plurality of sheets are stacked.
[0002]
[Prior art]
Sheet-like products such as X-ray film and recording paper are packaged in the form of a sheet assembly in which a plurality of sheets are stacked and shipped as products. For example, in the case of an X-ray film, a long film wound in a roll shape is cut into a predetermined length to form a sheet shape, and a plurality of sheets are stacked and stacked.
[0003]
In such a sheet-like product, particularly a photosensitive material such as an X-ray film, it is necessary to be able to easily identify the front and back directions by appearance in order to know which side the photosensitive surface is. . For this reason, a notch for identification is often formed on one side of the sheet. The notch for identification is formed in the vicinity of the corner of the sheet in a substantially circular shape of a certain size, and by checking which position the notch is in the left, right, up and down direction, The direction of the front and back of the sheet can be identified.
[0004]
In the manufacture of a sheet with a notch for identification as described above, a notch is formed simultaneously when cutting from a roll-shaped film into a sheet, and the sheet is aligned with the direction and position so that the front and back are not reversed. Laminate and become a sheet assembly, but when cutting, laminating, or conveying the sheet, etc., by subtle adjustment of the magnitude, direction, speed, etc. applied to the sheet from the manufacturing machine, The direction of some sheets may be reversed. However, in the product state sheet assembly, it is necessary to wrap the sheets in a state where all the directions of the sheets are aligned. Therefore, it is necessary to check whether or not all the directions of the sheets are aligned when the sheet is in the state of the sheet assembly.
[0005]
Therefore, when it is in the state of the sheet assembly, the position where the cutout should be placed is observed or taken by a video camera, a CCD image sensor, etc., and the presence or absence of the cutout is confirmed. If there is a notch, an apparatus for inspecting a sheet assembly that determines that the direction is correct and determines that the direction is different if there is no notch is used.
[0006]
As an inspection apparatus for the sheet assembly as described above, what is put into practical use by the present applicant will be described below. As shown in FIG. 12, such a sheet assembly inspection apparatus includes a video camera 102, a light source 103, a diffuser plate 104, and a monitor 105. The direction of the sheet 101 is inspected by observing the position. The video camera 102 is arranged to image the sheet assembly 100 from the stacking direction (Z-axis direction in the drawing), and transmits the captured image to the monitor 105. A light source 103 and a diffusion plate 104 are disposed at a position facing the video camera 102. Irradiation light from the light source 103 is diffused by the diffusion plate 104 and irradiated to a predetermined position where the notch 101a is to be disposed. In the case where all the sheet aggregates 100 are laminated in the normal direction, the light emitted from the light source 103 passes through the notches 101a in all layers and enters the video camera 102. The operator can observe the image around the notch 101a on the monitor 104 and confirm that all the directions of the sheet stack 100 are correctly aligned. In addition, when there is a sheet 101 having a different direction in the sheet assembly 100, the light emitted from the light source 103 is blocked by the sheet 101. Is incident. As a result, an image that is darker than the image when all the directions are aligned is displayed on the monitor 104, so that sheets stacked in different directions can be detected.
[0007]
Further, as another practical example, as shown in FIG. 13, it is arranged above or below the sheet stack 100 and irradiates the notch 101 a along the stacking direction of the sheet stack 100. Some include a reflective photosensor 106 including a light projecting element that emits light and a light receiving element that receives reflected light with respect to light emitted from the light projecting element. In this case, when all the sheets 101 are correctly aligned and laminated, the irradiation light irradiated from the light projecting elements passes through all the sheets 101, but there are sheets 101 having different directions. In that case, the irradiation light from the light projecting element is reflected by the sheet 101, the light receiving element of the photosensor 106 reacts, and it can be confirmed that there is a sheet having a different direction. In addition, in such a sheet integrated body inspection apparatus, a transmissive photosensor may be used instead of a reflective type.
[0008]
[Problems to be solved by the invention]
In the sheet stack inspection apparatus as described above, when the position of the cutout of the sheet stack is confirmed, the sheet stack is imaged from the sheet stacking direction or received by a photo sensor. If the position is shifted from front to back, left and right, even if the sheet is oriented in the normal direction, notches are not observed or the photosensor reacts when confirmed by the monitor.
[0009]
Therefore, a method of checking the position of the notch after aligning the positions of the four sides of the sheet accurately is considered, but a mechanism for aligning the positions of the four sides is introduced only for the inspection process for determining the direction. This is undesirable because it hinders cost reduction. Furthermore, even when a mechanism for aligning the positions of the four sides is introduced, if the transmittance of the X-ray film is high, it is difficult to capture a clear image with a video camera, or the reaction by the photosensor is unstable. Therefore, the sheet direction cannot be reliably inspected.
[0010]
An object of the present invention is to solve the above-described problems, and to provide a sheet stack inspection apparatus capable of reliably inspecting the direction of a sheet on which an identification notch is formed at low cost. To do.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the sheet stack inspection apparatus according to the present invention includes a plurality of sheets in which notches of a certain size are formed at certain locations on one side so that the front and back sides and the front-rear direction coincide with each other. Area type imaging means for imaging a laminated surface on one side, and an evaluation pattern formed by a series of notches on each laminated surface based on an imaging signal from the area type imaging means And an evaluation pattern extracting unit for determining whether or not sheets having different front and back or front and rear directions are mixed in the sheet assembly based on the continuity of the evaluation pattern.
[0012]
Note that the evaluation pattern extraction means includes binarization processing means for converting imaging signals obtained from the inside and outside of the cutouts of each sheet into binary signals that are opposite to each other, and a lamination boundary line between the sheets. It is preferable that the fine wire removal means to remove is included. It is also effective in the present invention that the area-type imaging means is supported so as to be movable in the sheet stacking direction.
[0013]
The sheet assembly inspection apparatus according to claim 4 is used to inspect a sheet assembly in which a plurality of sheets each having a notch of a certain size formed at a certain portion of one side are stacked so that the front and back sides and the front-rear direction coincide with each other. The line-type image pickup means in which the image sensor is arranged along the sheet surface direction and the line-type image pickup means are supported so as to face the laminated surface on one side, and the line-type image pickup means in the sheet stacking direction is relatively moved. Scanning means, edge extraction means for extracting one edge of a notch formed in each sheet based on an imaging signal obtained from the line-type imaging means along with movement by the scanning means, and edge extraction by the edge extraction means Determination means for determining whether or not sheets having different front and back or front and rear directions are mixed in the sheet stack based on presence or absence.
[0014]
The scanning means pitch-feeds the line-type imaging means by a certain distance in a direction orthogonal to the sheet stacking direction, and then moves the line-type imaging means in the sheet stacking direction. The edge extracting means is obtained from the line-type imaging means throughout the pitch feed. It is preferable to perform edge extraction based on the captured image signal. Moreover, it is preferable that the line-type imaging unit has an imaging lens that can be focused, and performs edge extraction by switching at least two focus positions.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram showing the configuration of an inspection apparatus for an X-ray film sheet assembly embodying the present invention. The X-ray film sheet assembly inspection apparatus 1 (hereinafter simply referred to as an inspection apparatus) includes a camera 2, a camera shift mechanism 3, a system controller 4, and an illumination apparatus 5. The sheet 11 constituting the obtained sheet assembly 10 is inspected for whether the front and back sides and the front and rear directions are all correctly aligned. The inspection process performed by the inspection apparatus 1 is performed in an inspection space that is light-tightly shielded from the surroundings so that the sheet 11 that is a photosensitive material is not exposed.
[0016]
The sheet assembly 10 is obtained by laminating a plurality of sheets 11 which are rectangular X-ray films used in medical imaging apparatuses. The sheet 11 is an X-ray film in the form of a long roll. Are cut into rectangular sheets, and when this cutting is performed, a notch 12 for identification is formed at the same time. The notch 12 is formed in a certain size at a certain position on one side of the sheet 11. Further, following the sheet cutting process, the sheets are laminated so that the front and back sides and the front and rear directions coincide with each other, and are formed into a sheet integrated body 10 and conveyed onto the work table 6.
[0017]
In this inspection apparatus 1, a coordinate system as shown in the arrow direction in FIG. 1 is set. The Z-axis direction is a stacking direction in which the sheets 11 are stacked, the Y-axis direction is a direction along one side where the notch 12 of the sheet 11 is formed, and the X-axis direction is the sheet 11 The surfaces are stacked and are orthogonal to the surface 10a including one side where the notch 12 is to be disposed, and the X, Y, and Z axis directions are orthogonal to each other.
[0018]
The camera shift mechanism 3 includes a moving table 15, a feed screw 16, a motor 17, a position detector 18, and a base member 19 to which these are attached. The base member 19 is formed with a guide groove 19a along the Z-axis direction, and the protrusion 20 of the movable table 15 is slidably fitted into the guide groove 19a. The movable table 15 includes a table base portion 21 and a flat surface portion 22 provided integrally with the table base portion 21. The camera 2 and the illumination device 5 are fixed to the plane portion 22. The base 21 is formed with a projection 20 and screwed with a feed screw 16. As the feed screw 16 rotates, the moving table 15 moves along with the camera 2 and the illumination device 5 along the Z-axis direction. A motor 17 serving as a drive source for rotating the feed screw 16 is controlled by the system controller 4 via a driver 23.
[0019]
The position detector 18 is provided integrally with the base member 19, and a resistor 24 is provided in the back of the long hole 18 a formed along the Z-axis direction. A protrusion 25 that is slidably fitted to the long hole 18 a is integrally provided on the base 21 of the movable base 15. A slider 26 that contacts the resistor 24 is provided at the tip of the protrusion 25. Thereby, the position detector 18 functions as a variable resistor in which the resistance of the resistor 24 increases as the slider 26 moves upward, and decreases as the slider 26 moves downward. The position can be detected. The position of the movable table 15 detected by the position detector 18 is transmitted to the system controller 4.
[0020]
The camera 2 is fixed to the movable table 15 so as to face the surface 10a of the sheet stack 10 and be aligned with the position where the notch 12 is to be arranged. As shown in FIG. The photographing optical axis direction L is arranged along the X-axis direction of the coordinate system described above, and the optical system 30 in which the focus adjustment is performed along the X-axis direction and the optical system 30 are arranged behind the optical system 30. It consists of a CCD image sensor (area sensor) 31 as an area type imaging means. Image data captured by the CCD image sensor 31 is transmitted to the system controller 4. Further, the optical system 30 is provided with an autofocus function, and focus adjustment is performed under the control of the system controller 4.
[0021]
The image captured by the camera 2 is an image in the imaging ranges 35, 36, 37, and 38 indicated by the dotted lines in FIG. 3 and is wider than the notch 12 and has a height corresponding to a plurality of sheets 11. An image can be taken. Furthermore, in the present embodiment, in order to reliably capture an image around the notch 12, the width A of the imaging range is about twice the width B of the notch 12, and the Y direction of the notch 12 is set. It corresponds to the variation of the position of. The camera 2 performs imaging while moving in the Z-axis direction by the camera shift mechanism 3, and sequentially from the imaging range 35 that images the lower part of the sheet stack 10 to the upper imaging ranges 36, 37, and 38. I will take a picture. The imaging ranges 35 to 38 are set so as to overlap in adjacent ranges 39, 40, and 41, respectively. Thereby, the camera 2 can image all the sheets from the lowermost layer to the uppermost layer of the sheet assembly 10.
[0022]
The illuminating device 5 irradiates infrared rays so that the sheet 11 is not exposed to light, and is connected to the control unit 43 via a cord 42. The illumination device 5 incorporates an optical fiber (not shown). Infrared rays are incident from an IRED disposed at one end of the optical fiber, and the other end is exposed from the tip of the illumination device 5. The front end of the illuminating device 5 is disposed so as to face the surface 10 b orthogonal to the surface 10 a among the surfaces on which the sheets 11 are stacked in the sheet assembly 10, and the control unit 43 causes the IRED to be a predetermined amount of light. When the light emission is controlled, the infrared rays of the IRED enter the inside of the sheet assembly 10 from the surface 10b through the optical fiber. The CCD image sensor 31 of the camera 2 can sense an infrared ray incident on the interior of the sheet assembly 10 and take an image of a peripheral portion at a position where the notch 12 is to be disposed.
[0023]
The system controller 4 determines from the image data of the imaging ranges 35 to 38 captured by the camera 2 whether sheets having different front and back or front and rear directions are mixed in the sheet assembly 10. The system controller 4 performs image processing on the imaging data input from the camera 2 and extracts an evaluation pattern, and the evaluation pattern extracted by the evaluation pattern extraction unit 45 from the evaluation pattern of the sheet assembly 10. A defect determination unit 46 that determines whether or not direction-defective sheets with the front and back and front and back reversed are mixed is connected.
[0024]
Image processing performed by the evaluation pattern extraction unit 45 on the image input from the camera 2 will be described below with reference to FIGS. The system controller 4 first performs fine line removal processing on the input image data (FIG. 4A) to remove the fine lines 47 corresponding to the boundary lines of the gaps where the sheets 11 are stacked. As a result, an image from which fine lines are removed as shown in FIG. In this thin line removal processing, the image data is divided into blocks of 9 pixels P1, P2, P3, P4, P5, P6, P7, P8, and P9 units each having three vertical and horizontal pixels as shown in FIG. The highest luminance replacement process is performed in which the highest luminance among the nine pixels P1 to P9 is selected, and all the luminances of the nine pixels P1 to P9 are replaced with the same luminance as the highest luminance pixel. If the width of the thin line corresponding to the gap between the sheets is set to be within 2 pixels, all the thin lines can be removed by the above-described maximum luminance replacement processing in units of 9 pixels. If the fine line 47 corresponding to the gap between the sheets is thicker and the maximum luminance replacement process in units of 9 pixels is not sufficiently removed, the block size for performing the maximum luminance replacement process is set to 16 pixels. Or a larger partition unit such as a unit of 25 pixels.
[0025]
Next to the thin line removal process, the system controller 4 binarizes the image data (FIG. 4C). This binarization compares the brightness of each part of the image data after the thin line removal processing with a preset reference brightness, and the white part 48 has a brightness higher than the reference brightness, and the brightness is lower than the reference brightness. The portion is a black portion 49. The portion where the inside of the notch 12 is imaged is located behind the surface 10 a on which the sheets 11 are laminated, and thus is processed into the black portion 49, and the portion other than the notch 12 is processed into the white portion 48. The As a result, the image data input from the camera 2 is extracted continuously from the notched portions of each sheet, and becomes an evaluation pattern in which the other portions are clearly distinguished. Sent to.
[0026]
In the image data shown in FIG. 4, all the directions of the sheet 11 are aligned, and the position where the notch 12 of the surface 10 a is to be disposed has a variation in the front and back positions, but the sheet 11 of all layers is cut. FIG. 6 shows image data when the notch 12 is located, and the image data of FIG. 6 described below is a case where there is a direction-defective sheet in the sheet assembly 10 in which the direction is different from other sheets. The image data is shown. In the image data of FIG. 6 as well, the thin line removal process is performed from the image data (FIG. 6A) input from the camera 2 (FIG. 6B), and the binary data is also obtained, as in the image data of FIG. The evaluation pattern (FIG. 6C) is formed so that the notched portions are continuous. Then, the evaluation pattern of FIG. 6C is also transmitted to the defect determination unit 46 as with the image data of FIG.
[0027]
In the defect determination unit 46, whether or not direction-defective sheets are mixed in the sheets 11 of the sheet assembly 10 based on the evaluation patterns (FIGS. 4C and 6C) extracted by the evaluation pattern extraction unit 45. Determine whether or not. In the evaluation pattern shown in FIG. 4C, the black portion 49 corresponding to the portion where the notch 12 is imaged forms a continuous image all along the Z-axis direction. The defect determination unit 46 determines that there is no orientation failure sheet in the sheet assembly 10. In the evaluation pattern shown in FIG. 6C, there is a portion where the black portion 49 is discontinuous with respect to the Z-axis direction, and since this portion does not have the notch 12, In this case, the defect determination unit 46 determines that there is a direction defective sheet in the sheet assembly 10.
[0028]
Next, the operation of the above configuration will be described using the flowchart of FIG. A sheet stack 10 that is cut into a rectangular shape having a notch for identification by a cutting device and stacked so as not to reverse the direction in a predetermined number of sheets by the stacking device is conveyed to the work table 6 by a belt conveyor or the like. come. Such a sheet assembly production system is described in detail in Japanese Patent Application No. 2001-005322, for example.
[0029]
When the sheet stack 10 is set on the workbench 6, the inspection apparatus 1 enters an inspection start state. In the initial position, the camera 2 and the illumination device 5 are positioned in accordance with the imaging range 35 of the lowermost layer of the sheet stack 10. When the inspection process starts, the CCD image sensor 31 is turned on, and when the focus adjustment of the optical system 30 is performed under the control of the system controller 4, the first imaging is performed. When the first imaging is performed, the camera shift mechanism 3 operates to move the camera 2 and the illumination device 5 in accordance with the position of the next imaging range 36. When moving to the position of the imaging range 36, the second imaging is performed as in the first imaging. Similarly, the imaging ranges 37 and 38 are imaged for the third and fourth times each time they are moved by the camera shift mechanism.
[0030]
When the first to fourth imaging is completed and the imaging of all sheets of the sheet assembly 10 is completed, the image data is transmitted to the evaluation pattern extraction unit 45. In the evaluation pattern extraction unit 45, the imaging ranges 35 to 38 are combined into one image data, and the above-described image processing is started. Then, the floor pattern created by performing the thin line removal process and the binarization process is transmitted to the defect determination unit 46. If the black portions 49 corresponding to the notches 12 are all continuous in the Z-axis direction from the evaluation pattern, the defect determination unit 46 determines that there is no direction-defective sheet in the sheet stack 10. The sheet assembly 10 that has been determined to have no orientation defect sheet is in a product state after being packed into a light-shielding bag and through a packing process into a decorative box, and is shipped to the market. If there is a portion in which the black portion 49 is not continuous in the Z-axis direction, it is determined that there is a defective sheet and a warning is given to the operator. In this way, the inspection apparatus 1 can reliably determine a misoriented sheet in the sheet stack 10 and adjusts the position of the notch 12 even if there is some variation. If the image is taken within the imaging range of the width, all the images around the notch can be imaged. Therefore, it is not necessary to introduce a mechanism for aligning the positions of the four sides of the sheet 11, and the cost can be reduced.
[0031]
In the first embodiment, an area sensor is used as an image sensor of a camera that captures an image around a notch. However, the present invention is not limited to this. It is possible to determine a defective sheet. Hereinafter, a second embodiment of the present invention using a line sensor as an image sensor will be described.
[0032]
As shown in FIG. 8, in the inspection apparatus 55 of this embodiment, a camera 57 incorporating a CCD image sensor (line sensor) 56 as a line-type imaging unit is used, and the other camera shift mechanism 3, system controller 4, About the illuminating device 5 grade | etc., It is the same as that of what is used in the said 1st Embodiment, and abbreviate | omits description.
[0033]
In the camera 57, in addition to the CCD image sensor 56, an optical system 31 similar to that of the first embodiment is incorporated. In the CCD image sensor 56, image pickup devices 56 a are arranged along the Y-axis direction so as to be parallel to the sheet 11. In the initial state, the camera 57 is positioned at a height that matches the upper end of the sheet stack 10, and is moved along the Z-axis direction by the camera shift mechanism 3 while notching the sheet stack 10. The peripheral images are taken line by line, and the sheets 11 of all layers are taken. In the first embodiment, since a wide imaging range is set so that all the notches 12 of the sheet 11 are imaged in the width direction, edges formed on both sides of the notch 12 are set. In the first embodiment, both sides are imaged. On the other hand, in the present embodiment, since the CCD image sensor is used in which the image sensor is arranged so as to be able to image in the range of the notch 12 and substantially the same width in the Y-axis direction, the image is captured by the camera 57. In the image to be displayed, only one edge 12a of the two edges 12a and 12b is captured.
[0034]
In the inspection apparatus 55 of this embodiment, the camera shift mechanism 3 and the optical system 31 are controlled according to the control pattern 60 as shown in FIG. 9, and the camera 57 is moved and the focus position is changed to capture a notch peripheral image. I will do it. Below, for convenience of explanation, the control pattern 60 is divided into five first, second, third, fourth and fifth control patterns 60a, 60b, 60c, 60d and 60e. First, in the first control pattern 60a, in setting the focus position, the focus position is fixed at a position farthest from the notch 12, that is, a position farther from the sheet stack in the X-axis direction, and imaging is started. The first control pattern 60a is completed when the camera 57 picks up the images of the sheets 11 of all the layers of the sheet assembly 10 while moving from the upper end to the lower end along the Z-axis direction by the camera shift mechanism 3. In the second control pattern 60b, first, the focus position moves to the back side of the notch 12, that is, the position closer to the sheet stack 10 in the X-axis direction, and the focus position is fixed to this position. Start imaging. Then, while moving from the lower end to the upper end along the Z-axis direction, the camera 57 images the sheets 11 of all layers of the sheet assembly 10 to complete the second control pattern 60b. Then, in the same manner, the focus position is moved to the back side of the notch 12 at regular intervals, and in the third and fifth control patterns 60c and 60e, the camera 57 is moved from the upper end to the lower end, In the fourth control pattern 60d, the camera 57 is moved from the lower end to the upper end, and images of the sheets 11 of all layers of the sheet stack 10 are taken. As a result, five types of notch peripheral image data having different focus positions are captured. When the imaging is completed, the camera 57 transmits five types of image data to the evaluation pattern extraction unit 45.
[0035]
In the evaluation pattern extraction unit 45 to which five types of image data having different focus positions are transmitted, there is a part in which an image processing method is different from that in the first embodiment. Image processing performed on the image data input by the evaluation pattern extraction unit 45 in this embodiment will be described below with reference to FIGS. 10 and 11, for convenience of explanation, description will be made using image data obtained by imaging only five sheets 11 stacked on the sheet stack 10. Furthermore, in the present embodiment, when the CCD image sensor 56 serving as a line-type imaging unit performs imaging, an image having a height corresponding to one sheet 11 is captured for three lines. That is, in the images shown in FIGS. 10 and 11, a total of 15 lines are imaged from the upper end to the lower end in order to capture 3 lines each for 5 sheets 11. In addition, the sheet 11 captured with the image data shown in FIGS. 10 and 11 will be described as sheets 11a, 11b, 11c, 11d, and 11e in order from the top for convenience of description.
[0036]
First, the system controller 4 applies the input image data (FIGS. 10A, 10B, 10C, 10D, and 10E) as shown in FIG. A compositing process for compositing to a single image is performed. In this composition processing, the images of the sheets 11a to 11e are compared with the images of FIGS. 10A to 10D, respectively. In this comparison, the image data that is in focus is selected from the five image data. That is, in the focused image data, the portion corresponding to the notch 12 should have low brightness, and the portion where one side of the sheet 11 is imaged should have high brightness. The one with the highest contrast with the lower part is selected. For example, in the image of 10 sheets 11c that match, the image data of FIG. 10A has the highest contrast, so the portion of the sheet 11c is selected from this image data. Similarly, the other lines 11a, 11b, 11d, and 11e are selected with the highest contrast, resulting in a composite image as shown in FIG.
[0037]
Next, the evaluation pattern extraction unit 45 performs a fine line removal process on the above-described composite image (FIG. 11B). The thin line removal process is the same as that described in the first embodiment. After the fine line removal process, the evaluation pattern extraction unit 45 performs an edge extraction process. In this edge extraction process, only the boundary line between the high luminance portion and the low luminance portion is extracted to make the black portion 61, and the other portions are all made white portion 62 (FIG. 11C). As a result, only the portion corresponding to the edge 12a of the notch 12 is extracted as the black portion 61, and the other portions are all removed image data, and this image data is transmitted to the defect determination unit 46 as an evaluation pattern.
[0038]
The defect determination unit 46 determines whether or not there is a directionally defective sheet in the sheet 11 of the sheet assembly 10 from the evaluation pattern (FIG. 11C). In the image data of FIG. 11C, the black portions 61 corresponding to the edges 12a of the notches 12 are formed in the portions of the sheets 11b, 11c, and 11d, but the black portions 61 are formed in the portions of the sheets 11a and 11e. Therefore, it can be seen that the cutout 12 is not present at this position for the sheets 11a and 11e. Therefore, the defect determination unit 46 determines that these sheets 11a and 11e are direction defective sheets and warns the operator. In this way, even if a line sensor is used, it is possible to reliably determine a direction-defective sheet in the sheet assembly 10.
[0039]
In the first embodiment, the position of the notch 12 varies greatly in the X-axis direction. For example, when the notch 12 is displaced more than the depth of the notch 12, the sheet of all layers is obtained only by one imaging. It is conceivable that an in-focus image of 11 cannot be obtained. In that case, as in the second embodiment, the optical system 31 is adjusted to capture a plurality of image data with different focus positions, and the focused data is transferred to the sheet as in the second embodiment. What is necessary is just to take out by the pixel unit equivalent to 1 sheet, and to process a composite image.
[0040]
In the first and second embodiments, an area sensor or a line sensor that captures an image in response to transmitted light is used. However, the present invention is not limited to this, and the sheet laminate 10 The surface 10a may be directly illuminated and imaged by the reflected light. In addition, when imaging using reflected light in this way, a diffused plate is provided to increase the brightness of the reflected light so that stable reflected light enters the area sensor or line sensor. Good. In addition, when imaging is performed in response to transmitted light as in the above-described embodiment, the number of times the illumination device 5 transmits the sheet 11 and enters the area sensor or line sensor is counted. The number of sheets 11 in the state of the sheet stack 10 can also be counted.
[0041]
【The invention's effect】
As described above, in the sheet stack inspection apparatus of the present invention, the area-type imaging unit that images the laminated surface on one side, and the notch of each sheet on the laminated surface based on the imaging signal from the area-type imaging unit. Evaluation pattern extraction means for extracting an evaluation pattern formed by a series, and determination means for determining whether sheets having different front and back or front and rear directions are mixed in the sheet assembly based on the continuity of the evaluation pattern Therefore, it is possible to reliably determine the sheet direction.
[0042]
In the sheet integrated inspection apparatus according to claim 4, a line type imaging unit having a resolution in a sheet surface direction, and supporting the line type imaging unit facing the laminating surface on one side, and stacking sheets A scanning unit that relatively moves the directional line type imaging unit; an edge extracting unit that extracts one edge of a notch formed in each sheet based on an imaging signal obtained from the line type imaging unit along with the movement of the scanning unit; And determining means for determining whether or not sheets having different front and back or front and rear directions are mixed in the sheet stack based on the presence or absence of edge extraction by the edge extracting means, so that the direction of the sheet is reliably determined. It is possible.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an inspection apparatus for a sheet assembly embodying the present invention.
FIG. 2 is a block diagram showing an electrical configuration of the sheet assembly inspection apparatus shown in FIG. 1;
3 shows a notch peripheral image of a sheet stack imaged by the sheet stack inspection apparatus shown in FIG. 1. FIG.
FIG. 4 is an explanatory diagram showing image data when image processing is performed on a notch peripheral image when all sheet directions are aligned.
FIG. 5 is an explanatory diagram showing a block of 9 pixel units that divides an image when performing fine line removal processing in the image processing shown in FIG. 4;
FIG. 6 is an explanatory diagram illustrating image data when image processing is performed on a notch peripheral image when there are direction-defective sheets having different directions.
FIG. 7 is a flowchart showing a flow of an inspection process in the sheet stack inspection apparatus embodying the present invention.
FIG. 8 is a schematic view showing an inspection apparatus for a sheet assembly according to another embodiment different from that shown in FIG.
FIG. 9 is an explanatory diagram showing a focus position pattern when a camera shift mechanism and a focus adjustment mechanism incorporated in the sheet stack inspection apparatus shown in FIG. 8 are operated;
FIG. 10 is an explanatory diagram showing a plurality of pieces of image data with different focus positions captured by the sheet stack inspection apparatus shown in FIG.
11 is an explanatory diagram showing image data when the image data shown in FIG. 10 is subjected to image processing by the sheet stack inspection apparatus shown in FIG. 8;
FIG. 12 is a schematic view showing a conventional sheet stack inspection apparatus.
13 is a schematic view showing a conventional sheet stack inspection apparatus using a method different from that shown in FIG.
[Explanation of symbols]
1,55 Sheet stack inspection system
2,57 camera
3 Camera shift mechanism
4 System controller
5 Lighting equipment
6 Working table
10 Sheet assembly
11 sheets
12 Notch

Claims (6)

In an inspection apparatus for a sheet assembly in which a plurality of sheets each having a notch of a certain size formed at a certain part of one side are laminated so that the front and back sides and the front-rear direction coincide with each other,
Area-type imaging means for imaging the laminated surface of the one side;
Evaluation pattern extraction means for extracting an evaluation pattern formed by a series of notches in each sheet on the laminated surface based on an imaging signal from the area-type imaging means, and front / back or front / rear based on continuity of the evaluation pattern And a determination unit for determining whether or not sheets having different directions are mixed in the sheet stack. The evaluation pattern extraction means removes the binarization processing means for converting the imaging signals obtained from the inside and outside of the cutouts of each sheet into a binarized signal opposite to each other, and the lamination boundary line between the sheets The apparatus for inspecting a sheet assembly according to claim 1, further comprising: a thin line removing unit that performs the operation. 3. The sheet assembly inspection apparatus according to claim 1, wherein the area-type imaging unit is supported so as to be movable in a sheet stacking direction. In an inspection apparatus for a sheet assembly in which a plurality of sheets each having a notch of a certain size formed at a certain part of one side are laminated so that the front and back sides and the front-rear direction coincide with each other,
Line-type image pickup means in which an image pickup device is arranged along the surface direction of the sheet;
Scanning means for relatively moving the line-type imaging means in the sheet stacking direction while supporting the line-type imaging means facing the laminated surface of the one side;
Edge extraction means for extracting one edge of a notch formed in each sheet based on an imaging signal obtained from the line-type imaging means together with the movement by the scanning means;
A sheet stack inspection apparatus comprising: a determination unit that determines whether or not sheets having different front and back or front and rear directions are mixed in the sheet stack based on presence or absence of edge extraction by the edge extraction unit. The scanning means pitch-feeds the line-type imaging means by a certain distance in a direction orthogonal to the sheet stacking direction, and then moves the line-type imaging means in the sheet stacking direction. 5. The sheet stack inspection apparatus according to claim 4, wherein edge extraction is performed based on the obtained imaging signal. 6. The sheet stack inspection apparatus according to claim 4, wherein the line-type imaging unit includes an imaging lens capable of focusing, and performs edge extraction by switching at least two focus positions.

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