JP2020030118A - Sheet wrinkle inspection device and wrinkle inspection method - Google Patents

Abstract

To provide a sheet wrinkle inspection device and a winkle inspection method capable of detecting a winding wrinkle of an inner peripheral side of a sheet to be wound around a winding core, reducing an inspection staff, and eliminating sanitary problems.SOLUTION: A device for detecting the presence/absence of a winding wrinkle of a resin film 1 includes: a plurality of illumination units 10 for irradiating light beams to an inspection region 5 of the transparent long resin film 1 to be newly wound around a paper pipe 2 being a core in a multilayer manner; an imaging camera 30 for imaging the inspection region 5 of the resin film 1 during being newly wound while irradiated by the light beams from the plurality of illumination units 10; and detection means 40 for detecting the presence/absence of a winding wrinkle 4 of the resin film 1 during being newly wound by using image information of the inspection region 5 of the resin film 1 imaged by the imaging camera 30. Since the presence/absence of the winding wrinkle 4 of the resin film 1 during being newly wounded is automatically inspected by imaging the resin film, a winding wrinkle 4 on an outer peripheral side and of the outermost periphery of a wrapped roll body 3 can be detected, and also, the winding wrinkle 4 on an inner peripheral side can easily be detected.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sheet wrinkle inspection apparatus and a sheet wrinkle inspection method for detecting the presence or absence of a sheet wrinkle when being wound around a core.

  As shown in FIG. 2, a conventional resin film 1 is formed into a transparent strip-like thin film with polyvinylidene chloride or the like and wound around a raw material. The raw material is wound into a paper core 2 as a winding core in multiple layers by a machine to form a packaging roll 3 (see Patent Documents 1 and 2). This packaging roll body 3 has low transparency because air is interposed between layers of the resin film 1 immediately after production, but becomes transparent when air is discharged from the layer of the resin film 1 to the outside as time passes. The performance is improved.

  By the way, as shown in FIG. 3, uneven wrinkles (wrinkles) 4 are often generated in the resin film 1 due to wrinkles and thickness of the raw material, misadjustment of a rewinding machine, and the like. If the wrinkles 4, especially the long wrinkles 4, are left as they are, the contact area between the resin film 1 and the packaged object (for example, food etc.) decreases, causing poor adhesion or the wrinkles 4. The resin film 1 is rolled into a knob-like shape, and the packaging roll body 3 becomes defective, or the appearance of the packaging roll body 3 is extremely deteriorated, resulting in quality deterioration.

  In view of the above, conventionally, when the packaging roll body 3 is manufactured, the presence or absence of the circumferential wrinkles 4 of the packaging roll body 3 immediately after the production is visually inspected, and the circumferential direction of the resin film 1 of the packaging roll body 3 is measured. If there is a long winding wrinkle 4, the packaging roll body 3 is excluded from the system as a defective product.

JP 2004-307173 A JP-A-61-37649

  After the conventional resin film 1 for food packaging is wound around the paper tube 2 in multiple layers as described above, the presence or absence of the wrinkles 4 is visually inspected. Although it can be detected, there is a problem that it is difficult to detect the wrinkles 4 on the inner peripheral side by visual inspection from the outside (see FIG. 4). In particular, the packaging roll body 3 immediately after production has low transparency because air is interposed between the resin films 1 that have been wound into multiple layers, so that the wrinkles 4 on the inner circumferential side near the paper tube 2 can be detected, for example. It is very difficult to detect the wrinkles 4 of the resin film 1 wound about 20 m around the paper tube 2.

  Conventionally, as a method for solving such a problem, (1) a method of gripping the manufactured packaging roll body 3 and detecting the wrinkles 4 on the inner peripheral side of the resin film 1 from the hardness of the gripped packaging roll body 3; (2) A method has been proposed in which a long-wavelength light beam such as an infrared ray is obliquely incident on the packaging roll 3 and the reflected light is measured to detect the wrinkles 4 on the inner peripheral side of the resin film 1 of the packaging roll 3. ing.

  However, in the case of the method (1), it is necessary to hold the packaging roll body 3, so that it is not possible to reduce the number of inspection personnel, and even if gloves for work are fitted, food sanitation is not possible. The above problems may occur. In the case of the method (2), since air is interposed between the resin films 1 of the packaging roll body 3 immediately after the production, the air becomes opaque, and the wrinkles 4 on the inner peripheral side of the resin film 1 are detected with high accuracy. It is not easy to do.

  The present invention has been made in view of the above, and is capable of detecting wrinkles on the inner peripheral side of a sheet wound around a core, reducing the number of inspection personnel, and eliminating a problem of hygiene. It is an object to provide a wrinkle inspection device and a wrinkle inspection method.

In the present invention, in order to solve the above problems, it is an apparatus for detecting the presence or absence of wrinkles of the sheet,
Illuminating means for irradiating a light beam onto a long sheet wound around a core, imaging means for imaging the sheet irradiated with the light beam from the illuminating means, and a sheet being wound using image information of the sheet imaged by the imaging means And a detecting means for detecting the presence or absence of wrinkles.

Note that an image display unit that displays an image of the sheet captured by the imaging unit can be included.
Further, the sheet is preferably a substantially transparent resin sheet or resin film for packaging, which is wound around the core using air and static electricity.
Further, the detecting means can use image information of a portion other than the winding start portion of the sheet in which the winding start portion is wound around the core.

Further, the detecting means has a function of converting image information of the sheet being wound captured by the imaging means into a detection value, a function of comparing the converted detection value with a threshold value, and a function of performing the winding based on the result of the comparison. And a function of determining whether or not the sheet has a wrinkle.
The detecting means has a function of determining that a wrinkle has occurred in the sheet being wound when the detected value is equal to or greater than the threshold value as a result of the comparison, and a function for determining that the detected value is less than the threshold value as a result of the comparison. And a function of determining that no wrinkles have occurred in the sheet being wound.

  Further, in the present invention, in order to solve the above problem, it is possible to detect the presence or absence of a wrinkle of a sheet being wound on a core by using the sheet wrinkle inspection device according to any one of claims 1 to 4. Features.

  Here, the sheet in the claims includes a flexible resin sheet or a resin film, and is not particularly limited to transparent, opaque, and translucent. This sheet is mainly for food packaging, but may be various packaging sheets for chemicals, apparel, miscellaneous goods, and industrial materials. The winding end portion of the sheet can be turned back to be a knob for pulling out the sheet. Further, the number of illumination means and the number of imaging means may be one or plural. The image information of the imaging means includes at least density, luminance, color information, and the like.

  According to the present invention, since the presence or absence of wrinkles of a sheet being wound is imaged and automatically inspected, it is possible to detect the wrinkles on the outer peripheral side and the outermost periphery of the wound multilayer sheet. Wrinkles on the circumferential side can be detected. In addition, since there is no need to hold the wound multilayer sheet for inspection, it is possible to reduce the number of inspection personnel and the work time.

  According to the present invention, it is possible to detect wrinkles at least on the inner peripheral side of the inner and outer peripheries of a sheet wound around a core, thereby reducing inspection personnel and eliminating hygiene problems. effective.

According to the second aspect of the present invention, since the image of the sheet taken by the image pickup means is displayed on the image display means, it is possible to visually grasp the presence or absence of the wrinkle of the sheet and to contribute to the inspection of the sheet for wrinkles.
According to the third aspect of the present invention, a wrinkle always occurs at the winding start portion of the sheet wound around the core. However, since the image information of the wrinkle is not used, the wrinkle of the sheet is not used. Can be prevented from being erroneously detected.

  According to the invention described in claim 4, the detecting means has a function of converting image information of the sheet being wound captured by the imaging means into a detection value, a function of comparing the converted detection value with a threshold value, According to the result of the above, a function of determining the presence or absence of the wrinkle of the sheet being wound is realized, so that the wrinkle of the sheet can be detected automatically and with high accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall explanatory view schematically showing an embodiment of a sheet wrinkle inspection apparatus and a sheet wrinkle inspection method according to the present invention. It is a perspective explanatory view which shows typically the packaging roll body which wound the resin film around the paper tube. It is a perspective explanatory view showing typically a case where a wrinkle exists in the perimeter side of the resin film of a packaging roll body. It is an end surface explanatory view which shows typically the case where a winding wrinkle exists in the inner periphery of the resin film of a packaging roll body.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 4, a sheet wrinkle inspection apparatus according to the present embodiment determines whether or not a long wrinkle 4 of a long resin film 1 exists. A plurality of lighting units 10 for a resin film 1 to be wound around a paper tube 2 as a winding core, and an imaging for imaging the resin film 1 being re-wound which is illuminated by the plurality of lighting units 10. The camera 30 is provided with detection means 40 for detecting the presence or absence of a wrinkle 4 on the resin film 1 during rewinding based on image information of the resin film 1 captured by the imaging camera 30.

  The resin film 1 is formed into a transparent belt-like flexible thin film by using polyvinylidene chloride, polyvinyl chloride, polyethylene, or the like having excellent antifouling properties, moisture-proofing properties, and adhesion. It is re-wound by a winding method to form a packaging roll 3 for food packaging. The resin film 1 for food packaging has dimensions of 45 cm × 50 m, 45 cm × 55 m, 45 cm × 100 m, 30 cm × 30 m, 30 cm × 100 m, 30 cm × 110 m, and 22 cm × 100 m which do not excessively stretch.

  The paper tube 2 is formed into a slender cylindrical shape having excellent dustproofness and surface smoothness, for example, by winding recycled paper in a spiral winding. After being supplied to a rewinding machine, a long resin film is formed on the outer peripheral surface. 1 can be wound in multiple layers at high speed using air and static electricity. A length measuring device such as an encoder for calculating the remaining amount of the raw material and the amount of rewinding of the resin film 1 is selectively mounted on the rewinding machine. The rewinding of the film 1 becomes possible.

  As shown in FIG. 1, a plurality of (two units in the present embodiment) lighting units 10 are disposed in a rewinding machine, are arranged at a predetermined distance above the outer peripheral surface of the paper tube 2, and are obliquely juxtaposed. A linear light beam (see the arrow in FIG. 1) is evenly applied to the inspection area 5 of the long resin film 1 which is being wound around the tube 2 so as to project the resin film 1 and generate halation on the resin film 1. Function. The plurality of lighting units 10 are arranged at predetermined intervals in the radial direction of the paper tube 2 and are connected to a controller 20 for control. Each lighting unit 10 is not particularly limited, but is configured as a small unit from the viewpoint of providing a required number of LEDs with low power consumption and a long life, and enabling easy installation in a small space.

  As shown in FIG. 1, the imaging camera 30 is not particularly limited. For example, the imaging camera 30 includes a small CCD camera with high sensitivity and low noise, or a small CMOS camera with a simple configuration and low cost. 2 is installed at a predetermined distance just above the outer peripheral surface of the resin film 1 and is connected to the controller 20 for control. Function to capture images.

  The imaging camera 30 is disposed in the rewinding machine and is located between the plurality of lighting units 10, and is located above the plurality of lighting units 10. The lens of the imaging camera 30 has a large depth of focus when the focus position of the inspection area 5 of the resin film 1 is shifted toward the front as the winding diameter of the resin film 1 increases.

  The imaging camera 30 is controlled to take an image of a portion other than the winding start end of the resin film 1 around which the winding start end is wound around the paper tube 2 as necessary. This is because a wrinkle 4 always occurs at the winding start end of the resin film 1 wound around the paper tube 2 by static electricity, so that the necessity of detecting the wrinkle 4 is low. In addition, when the rewind position of the resin film 1 moves, the imaging camera 30 is installed to be able to move up and down with respect to the outer peripheral surface of the paper tube 2 as necessary.

  As shown in the figure, the detecting means 40 is, for example, a personal computer or the like in which dedicated inspection software is installed, and a controller 20 and a monitor that displays an image of the inspection area 5 of the resin film 1 captured by the imaging camera 30. 41 via a cable.

  The detection unit 40 performs pre-processing (for example, image shading processing) on the image information (optical density or the like measured in the image) of the inspection area 5 of the resin film 1 in the middle of rewinding captured by the imaging camera 30. Etc.) to convert the detected value to a detected value, a function to compare the converted detected value with a preset threshold for a certain period of time, When the detection value is less than the threshold value as a result of comparing the function of determining that the long wrinkle 4 has occurred in the resin film 1 in the middle with the predetermined time, the long wrinkle 4 has occurred in the resin film 1 during the rewinding. And a function of determining that the data is not present.

  When realizing this function, it is preferable that the detecting means 40 use the image information of a portion other than the winding start end of the resin film 1 having the winding start end wound around the paper tube 2. This is because a wrinkle 4 always occurs at the winding start end of the resin film 1 wound around the paper tube 2 by static electricity, so that the necessity of detecting the wrinkle 4 is low, and there is a risk of erroneous detection. Because. Further, the threshold value to be compared with the detection value is set in consideration of the length of the wrinkle 4 which is a practical problem.

  In the above configuration, when the transparent resin film 1 is wound around the paper core 2 from the raw material and the presence or absence of the wrinkles 4 at the time of this winding is detected, the paper core 2 is supplied to the winding machine, The lighting unit 10 and the imaging camera 30 are each activated, and the end of the resin film 1 of the raw material is wound around the outer peripheral surface of the paper tube 2 as a start end by using static electricity. Are rotated, and the long resin film 1 is gradually wound around the paper tube 2 to form a multilayer packaging roll 3.

  At this time, wrinkles 4 always occur at the winding start end of the resin film 1, but long wrinkles 4, short wrinkles 4, and fine wrinkles 4 occur in the circumferential direction at portions other than the winding start end. May be. The wrinkles 4 have a feature that when they move as a whole, they do not overlap at the same position in the width direction. In addition, the inspection area 5 of the resin film 1 during the rewinding is illuminated by the plurality of illumination units 10 and is continuously imaged by the imaging camera 30, so that the image captured by the imaging camera 30 is displayed on the monitor 41. Then, the image information is continuously output to the detecting means 40.

  Next, the detecting means 40 pre-processes the image information of the inspection area 5 of the resin film 1 during the rewinding, which is captured by the imaging camera 30, converts the image information into a detection value, and converts the converted detection value and a preset threshold value. Are compared for a certain period of time. At this time, the detected value is higher when the inspection area 5 of the resin film 1 has the uneven wrinkles 4 and the amount of transmitted light is small, because the pixel density of the image information is high. When long wrinkles 4 having long irregularities are present in the inspection area 5 of the film 1 and the amount of transmitted light is very small, the pixel density of the image information becomes very high and the value becomes extremely high. On the other hand, when the wrinkles 4 do not exist in the inspection area 5 of the resin film 1, the amount of light transmission increases and the pixel density of the image information decreases, so that the value decreases.

  If the detection value is equal to or greater than the threshold value as a result of the comparison for a certain period of time, the detection means 40 determines that a long wrinkle 4 has occurred in the inspection area 5 of the resin film 1 being re-wound. 1 is interrupted, and the resin film 1 is discarded outside the system. On the other hand, if the detection value is less than the threshold value as a result of the comparison for a certain period of time, it is determined that no long wrinkles 4 have occurred in the resin film 1 being re-wound, and The packaging roll 3 is handled as a non-defective product.

  If it is determined that the long wrinkles 4 have occurred in the inspection area 5 of the resin film 1 during the rewinding, the rewinding of the resin film 1 may be interrupted, but the rewinding of the resin film 1 is continued. In addition, the packaging roll 3 after the completion of the rewinding of the resin film 1 can be discharged out of the system as a defective product.

  According to the above, the presence or absence of the wrinkles 4 of the resin film 1 during the production of the packaging roll body 3 is continuously imaged, not immediately after or immediately after the production of the packaging roll body 3, and the inspection is automatically performed. In addition to detecting the long wrinkles 4 on the outer peripheral side and the outermost periphery of the roll body 3, the long wrinkles 4 on the inner peripheral side near the paper tube 2 can be easily detected. By this detection, for example, the presence or absence of the long wrinkles 4 of the resin film 1 wound about 20 m around the paper tube 2 can be easily determined. Further, since there is no need to hold the packaging roll body 3 and inspect the presence or absence of the wrinkle 4 due to the strength of the winding hardness, it is possible to reduce the number of inspection personnel and the working time, and furthermore, in terms of food hygiene. There is no possibility that the problem described above may occur.

  Further, since the resin film 1 during the rewinding is inspected, it is possible to detect the long wrinkles 4 on the inner peripheral side of the resin film 1 with high accuracy regardless of the transparency of the resin film 1. In addition, since the image of the inspection area 5 of the resin film 1 captured by the imaging camera 30 is displayed on the monitor 41, the presence or absence of the wrinkle 4 can be visually grasped, and the inspection can be facilitated. .

  For example, in the case where the rewind end portion of the resin film 1 is turned back to be a knob 6 for pulling out the resin film 1, for example, the detecting means 40 erroneously detects the folded knob 6 of the resin film 1 as a wrinkle 4. Even so, if the display on the monitor 41 is utilized, it is possible to correct the erroneous detection of the detecting means 40, and it is possible to effectively prevent erroneous defective product certification of the packaging roll body 3. In addition, it is possible to effectively prevent the resin film 1 from being wound into a knob-like shape due to the wrinkle 4 and the packaging roll body 3 from becoming defective. Furthermore, since the resin film 1 is wound around the paper tube 2 by using air and static electricity, the resin film 1 can be closely attached to adjust the appearance of the packaging roll body 3.

  In the above embodiment, the transparent resin film 1 is wound around the paper tube 2 from the raw material, but the raw material may be omitted and the resin film 1 may be wound around the paper tube 2. In the above embodiment, a single imaging camera 30 is used, but the invention is not limited to this. For example, when the rewinding portion of the resin film 1 in the rewinding machine is narrow, a plurality of imaging cameras 30 may be used side by side, such as diagonally above, beside, diagonally below the paper tube 2 in the axial direction.

  In this case, the results of all the wrinkles 4 in the width direction of the resin film 1 may be aggregated, and the ratio of the wrinkles 4 occurring in the entire width of the resin film 1 may be obtained as the inspection result of the wrinkles 4. Instead of continuous imaging using moving images, a still image may be continuously captured by the imaging camera 30 and whether or not the inspection area 5 of the resin film 1 has the wrinkle 4 may be detected.

  When a plurality of imaging cameras 30 are provided, the detection unit 40 detects pre-processed image information (for example, pixel density, etc.) of the inspection area 5 of the resin film 1 during rewinding, which is captured by each imaging camera 30. A function of converting the detected value into a value, a function of adding the converted detected value, a function of comparing the total value of the added detected value and a preset threshold value for a certain period of time, and a result of the comparison, the total value of the detected values. Is greater than or equal to the threshold value, the function for determining that a long winding wrinkle 4 has occurred in the resin film 1 during rewinding, and, as a result of comparison, when the total value of the detected values is less than the threshold value, A function of determining that the long wrinkles 4 have not occurred in the resin film 1. Further, the detection unit 40 can use the image information of the portion other than the winding end portion of the resin film 1 wound around the paper tube 2.

  The sheet wrinkle inspection apparatus and the wrinkle inspection method according to the present invention are used in the field of manufacturing a sheet made of a resin sheet, a resin film, or the like.

1 resin film (sheet)
2 paper core (core)
3 Packaging roll body 4 Wrinkles 5 Inspection area 10 Lighting unit (lighting means)
20 controller 30 imaging camera (imaging means)
40 detection means 41 monitor (image display means)

Claims (5)

  A sheet wrinkle inspection device that detects the presence or absence of wrinkles in a sheet, an illumination unit that irradiates a light beam to a long sheet wound around a core, and an imaging unit that captures an image of the sheet irradiated with the light beam from the illumination unit. A sheet wrinkle inspection apparatus, comprising: a detection unit configured to detect presence or absence of a wrinkle of the sheet being wound using image information of the sheet captured by the imaging unit.   2. The sheet wrinkle inspection apparatus according to claim 1, further comprising an image display unit that displays an image of the sheet captured by the imaging unit.   The sheet wrinkle inspection apparatus according to claim 1, wherein the detection unit uses image information of a portion other than the winding start portion of the sheet around which the winding start portion is wound.   The detection unit has a function of converting image information of the sheet being wound captured by the imaging unit into a detection value, a function of comparing the converted detection value with a threshold, and a function of detecting the value of the sheet being wound according to the comparison result. 4. The sheet wrinkle inspection device according to claim 1, wherein the device determines a presence or absence of a wrinkle.   A wrinkle inspection method for a sheet, comprising using the sheet wrinkle inspection apparatus according to any one of claims 1 to 4 to detect the presence or absence of a wrinkle of the sheet being wound around the core.

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