JP4858711B2 - Tire inspection method and apparatus - Google Patents

Description

  The present invention relates to a tire inspection method and apparatus for nondestructively inspecting the state of a carcass cord of a tire having a metal carcass cord, such as a truck tire or a bus tire.

  In general, as an inspection method for this type of tire, an X-ray is emitted from the inner peripheral surface side of the tire toward the tire, and the image pickup device is disposed on the outer peripheral surface side of the tire while rotating the tire in the circumferential direction. In addition to taking a transmitted X-ray image that has passed through the tire by the display, the taken image is displayed on the display device, and the inspector visually determines the state of the carcass cord in the image displayed by the display device. It has been known.

In addition, as another tire inspection method, a transmission X-ray image is captured by the imaging device as described above, and the reference data stored in advance is compared with the captured image, and the reference data is captured. An apparatus that determines the state of a belt cord based on a difference from an image is known (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 9-15172

  By the way, in the former inspection method, since the inspector visually determines the state of the carcass cord, etc., it is difficult to improve the determination accuracy and it is difficult to shorten the time required for the inspection. there were.

  In the latter inspection method, reference data stored in advance and a captured image are compared, and a belt code state or the like is determined based on a difference between the reference data and the captured image. Since the reference data is created by imaging a plurality of tires and averaging each image, for example, it is possible to accurately make a detailed determination of the presence or absence of an open code in which the carcass code interval is partially widened. There was a problem that it was not possible.

  Further, since it is necessary to create and store the reference data for each tire type, there is a problem that the time required for the inspection is increased by the amount of creation of the reference data.

  The present invention has been made in view of the above problems, and the object of the present invention is to inspect a tire that can accurately determine the presence or absence of an open code and can reduce the time required for the inspection. It is to provide a method and apparatus thereof.

  In order to achieve the above object, the present invention irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire, and transmits the tire by an imaging device disposed on the outer peripheral surface side of the tire. In a tire inspection method for capturing an image of a transmitted electromagnetic wave and inspecting whether or not an open cord having a partially enlarged carcass cord interval has occurred in the tire from which the transmitted electromagnetic wave image has been captured, An extraction step for extracting the area where the code is imaged, a binarization step for binarizing the extracted image extracted by the extraction step, and a carcass code in the image binarized by the binarization step. The inspection line adding step for adding at least one inspection line extending in the intersecting direction and the range intersecting with the carcass code are differentiated. A difference step for obtaining an image of the inspection line and an average value calculating step for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line by the difference in the range intersecting the carcass code And a determination step for determining that an open code is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than or equal to a predetermined magnification with respect to the average value calculated by the average value calculation step. Is included.

  The present invention also provides an irradiation device that irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire, and a transmitted electromagnetic wave image that is disposed on the outer peripheral surface side of the tire and transmits through the tire. In a tire inspection apparatus for inspecting whether or not an open cord having a partially enlarged carcass cord interval has occurred in a tire that has captured a transmission electromagnetic wave image, the carcass cord is obtained from an image captured by the imaging device. Means for extracting a region where the image is captured, binarizing means for binarizing the extracted image extracted by the extracting means, and crossing the carcass code in the image binarized by the binarizing means Inspection line adding means for adding at least one inspection line extending in the direction to be scanned, difference means for obtaining an image of the inspection line in which the range intersecting the carcass code is differentiated, An average value calculating means for calculating an average value of the lengths of a plurality of divided inspection lines obtained by dividing the range intersecting with the cascode, and an average value calculated by the average value calculating means On the other hand, there is provided a determination unit that determines that an open cord is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than or equal to a predetermined magnification.

  Thereby, while extracting the area | region where the carcass code was imaged from the image imaged with the imaging device, the extracted extraction image is binarized and the direction which cross | intersects a carcass code in the binarized image At least one inspection line extending to the carcass code is added to obtain an image of the inspection line in which the range intersecting the carcass code is subtracted, and the inspection line is divided by subtracting the range intersecting the carcass code An average value of the lengths of the plurality of divided inspection lines is calculated, and if there is a divided inspection line having a length greater than or equal to a predetermined magnification with respect to the average value, an open cord is formed on the tire capturing the transmitted electromagnetic wave image. For example, the inspection line is provided so as to intersect the carcass cord substantially perpendicularly, and a part of the carcass cord in the captured image is determined. If the interval is open code is wider than the average value has occurred, a predetermined ratio or more of the length of the split test line is generated with respect to the average value, it is determined that the open code is generated.

  Further, the present invention irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire and transmits a transmitted electromagnetic wave image transmitted through the tire by an imaging device disposed on the outer peripheral surface side of the tire. In a tire inspection method for inspecting whether or not an open cord having a partially enlarged carcass cord interval has occurred in a tire that has picked up an image of a transmitted electromagnetic wave, the image picked up by the image pickup device is binarized. A binarization step and an inspection line addition step of adding at least one inspection line extending in a direction intersecting the carcass code in a range where the carcass code in the image binarized by the binarization step is captured A difference step for obtaining an image of an inspection line in which a range intersecting with the carcass code is differentiated, and a range intersecting with the carcass code being differentiated An average value calculating step for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line, and a length greater than or equal to a predetermined magnification with respect to the average value calculated by the average value calculating step A determination step for determining that an open cord has occurred in the tire that has captured the transmitted electromagnetic wave image if there is a division inspection line.

  The present invention also provides an irradiation device that irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire, and a transmitted electromagnetic wave image that is disposed on the outer peripheral surface side of the tire and transmits through the tire. In a tire inspection apparatus for inspecting whether or not an open cord having a partially wide carcass cord interval has occurred in a tire that has captured a transmission electromagnetic wave image, the image captured by the imaging apparatus is binarized. A binarization unit for performing binarization processing, and an inspection for adding at least one inspection line extending in a direction intersecting the carcass code in a range where the carcass code in the image binarized by the binarization unit is captured The line adding means, the difference means for obtaining an image of the inspection line in which the range intersecting the carcass code is differentiated, and the inspection by the difference in the area intersecting the carcass code An average value calculating means for calculating an average value of the lengths of a plurality of divided inspection lines formed by dividing the line, and for a divided inspection having a length greater than a predetermined magnification with respect to the average value calculated by the average value calculating means When there is a line, there is provided a determination unit that determines that an open cord is generated in the tire that has captured the transmitted electromagnetic wave image.

  As a result, the image picked up by the image pickup apparatus is binarized and at least one inspection line extending in a direction intersecting the carcass code in the range where the carcass code in the binarized image is picked up To obtain an image of the inspection line in which the range intersecting with the carcass code is differentiated, and by dividing the inspection line by dividing the range intersecting with the carcass code. When the average value of the length is calculated and there is a division inspection line having a length greater than or equal to a predetermined magnification with respect to the average value, it is determined that an open cord has occurred in the tire that has captured the transmitted electromagnetic wave image. For example, the inspection line is provided so as to intersect the carcass cord substantially perpendicularly, and the interval between some of the carcass cords in the captured image is larger than the average value. If the open cord has occurred Te Kuna' predetermined ratio or more of the length of the split test line is generated with respect to the average value, it is determined that the open code is generated.

  According to the present invention, for example, the inspection line is provided so as to intersect the carcass cord substantially perpendicularly, and the interval between some of the carcass cords in the captured image is wider than the average value so that the open cord is If it occurs, a division inspection line having a length greater than or equal to the predetermined magnification with respect to the average value is generated, and it is determined that an open code has occurred. Therefore, the predetermined magnification is appropriately set according to the tire type and the like. By setting, the presence / absence of an open code can be accurately determined. In addition, it is possible to make a determination automatically without using visual inspection, and it is not necessary to create reference data for each tire type, which is extremely advantageous in reducing the time required for inspection.

  1 to 18 show an embodiment of the present invention. FIG. 1 is a schematic diagram of an irradiation device and an imaging device, FIG. 2 is a block diagram of a tire inspection device, and FIG. 3 is a control unit of the first control device. FIG. 4 to FIG. 13 are schematic diagrams of images processed by the control unit of the first control device, FIG. 14 is a flowchart showing the operation of the control unit of the second control device, and FIGS. It is the schematic of the image processed by the control part of 2 control apparatuses.

  The tire inspection apparatus of the present embodiment is disposed on the inner peripheral surface side of the tire T, and is disposed on the outer peripheral surface side of the tire T and the irradiation device 10 that irradiates X-rays toward the tire T, and transmits through the tire T. An imaging apparatus 20 that captures a transmitted X-ray image as a transmitted electromagnetic wave image, and an inspection apparatus main body 30 connected to the imaging apparatus 20 are provided. The tire T is rotatably supported by a support device (not shown). The tire T is a radial tire arranged such that a plurality of metal carcass cords CC extend in the radial direction. A plurality of belt members are provided on the outer peripheral surface side of the tire T, and each belt member has a metal belt cord BC. The carcass cords CC are arranged at substantially equal intervals in the circumferential direction of the tire T so that the intervals of the carcass cords are substantially equal to each other. May be wider for code spacing. Such a phenomenon that the carcass cord interval is partially widened is called an open code.

  The irradiation device 10 is formed of a known X-ray tube that radiates X-rays radially, and is arranged on the inner peripheral surface side of the tire T supported by the support device. It is also possible to configure so that γ rays are irradiated instead of X rays.

  The imaging device 20 includes an upper camera 21 disposed on the upper side of the tire T supported by the support device, and a pair of side cameras 22 disposed on both sides in the width direction of the tire T supported by the support device. Each of the cameras 21 and 22 is a known line sensor camera, and each of the cameras 21 and 22 captures a transmission X-ray image transmitted through the tire T in a linear shape. That is, a transmission X-ray image for one round of the tire T is taken by taking images at predetermined intervals by the cameras 21 and 22 while rotating the tire T at a predetermined speed in the circumferential direction by the support device.

  As shown in FIG. 2, the inspection apparatus main body 30 includes first to third control apparatuses 31, 32, and 33. Each of the control devices 31, 32, 33 includes control units 31a, 32a, 33a, display units 31b, 32b, 33b such as a liquid crystal display screen, and storage units 31c, 32c, 33c such as a hard disk. The control units 31a, 32a, and 33a are well-known microcomputers having an arithmetic device, a storage device, an input device, and the like. Furthermore, an image captured by the upper camera 21 in the imaging device 20 is transmitted to the control unit 31a of the first control device 31, and an image captured by one side camera 22 among the side cameras 22 is subjected to the second control. An image transmitted to the control unit 32 a of the device 32 and captured by the other side camera 22 among the side cameras 22 is transmitted to the control unit 33 a of the third control device 33.

  In the tire inspection apparatus configured as described above, the camera 21 and 22 perform imaging at predetermined intervals while rotating the tire T in the circumferential direction at a predetermined speed by a support device (not shown) as described above. A transmission X-ray image of one round of the tire T is captured, and images captured by the cameras 21 and 22 are transmitted as digital images to the control units 31a, 32a, and 33a of the control devices 31, 32, and 33, respectively. In addition, it is also possible to create an image for one round of the tire T by connecting the linear imaging data captured by the cameras 21 and 22 in the control devices 31, 32, and 33.

  Subsequently, the control units 31a, 32a, and 33a of the control devices 31, 32, and 33 perform image processing of an image for one round of the tire T, and determine whether or not there is an open code based on the image processed image. The operation of the control units 31a, 32a, 33a of the control devices 31, 32, 33 at this time will be described below.

  First, operation | movement of the control part 31a of the 1st control apparatus 31 is demonstrated, referring the flowchart shown in FIG. Here, the image for one round of the tire T transmitted to the control unit 31a of the first control device 31 is taken from the radially outer side of the tire T, and each belt member is arranged at the center side in the width direction of the image. A plurality of metal belt cords BC are imaged, and a plurality of metal carcass cords CC constituting the carcass member are imaged on both sides of the belt cord BC in the width direction (see FIG. 4). FIG. 4 shows a part of an image for one round of the tire T. FIG. The carcass cords CC are arranged so as to extend in the image width direction, and are arranged at intervals in the vertical direction of the image. The belt cords BC are arranged so as to form a predetermined angle with the carcass cord CC, and are arranged at intervals in the vertical direction of the image. Here, images other than each belt code BC and each carcass code CC are not captured in the image transmitted from the upper camera 21. For example, when a background is captured in the image transmitted from the upper camera 21, each of the images transmitted from the upper camera 21 is subjected to differential processing from the transmitted image. It is preferable to remove things other than the belt cord BC and each carcass cord CC.

  First, when an image for one round of the tire T is transmitted from the upper camera 21 to the control unit 31a of the first control device 31 (SA1), the contrast of the image is enhanced (SA2). This contrast enhancement is performed using a known process such as a linear conversion process, a binarization process, and a luminance slicing process. Thereby, each belt code BC and each carcass code CC in the image are clarified (see FIG. 5). It is also possible to perform step SA3 and subsequent steps without performing step SA2.

  Subsequently, the component in the vertical direction of the image (the direction substantially perpendicular to the direction in which each carcass code CC extends) is emphasized in the image with enhanced contrast (SA3). The enhancement of the component in the vertical direction of the image is performed by a known method using, for example, a shift process and a differential process in the vertical direction of the image. Thereby, each belt code BC in the image is emphasized, and each carcass code CC is thinned or removed (see FIG. 6).

  Subsequently, the contrast of the image in which the vertical component of the image is enhanced is enhanced (SA4). This contrast enhancement is performed using a known process such as a linear conversion process, a binarization process, and a luminance slicing process. Thereby, each belt code BC in the image becomes clear (see FIG. 7).

  Subsequently, a region where the components (each belt code BC) emphasized in step SA3 are gathered in the image in which the contrast is enhanced in step SA4 is determined (SA5). This region determination is performed, for example, by appropriately performing shift processing and addition processing in the vertical direction of the image to fill the region in which the components emphasized in step SA3 are gathered (see FIG. 8), and then, for example, a Prewitt filter or a Sobel filter By performing edge emphasis processing using, the outline OL of the region having the largest area among the regions where the components emphasized in step SA3 are gathered is created (see FIG. 9). In this case, the inside of the contour line OL is a definite region where the components emphasized in step SA3 are gathered. Note that by performing expansion processing instead of the shift processing and addition processing, it is also possible to fill the region where the components emphasized in step SA3 are gathered. It is also possible to determine the region based on an average density per unit area (for example, a range of several pixels × several pixels).

  Subsequently, only a region other than the fixed region surrounded by the contour line OL is extracted from the image before the contrast is enhanced in step SA2 (SA6). Here, if images other than each belt code BC and each carcass code CC are not captured in the image before enhancing the contrast, the extracted image obtained by extracting only the range outside the contour OL is the carcass code CC. The imaged area is extracted (see FIG. 10). Note that an extracted image can be created from the image in which the contrast is enhanced in step SA2 or other images.

  Subsequently, the extracted image extracted in step SA6 is binarized (SA7). Here, the extracted image is divided into a plurality of ranges each having a predetermined area (for example, 15 pixels × 15 pixels), the average value of the gradation of the pixels in the range is calculated for each range, and each average value is set as a threshold value. Is used to perform dynamic binarization processing for binarizing each range. Thereby, each carcass code CC becomes clear in the extracted image (see FIG. 11). For example, when each pixel of the extracted image has 256 gradations, each carcass code CC becomes 0 gradation (black), and a portion other than each carcass code CC becomes 255 gradation (white). . Note that a normal binarization process may be performed instead of the dynamic binarization process.

  Subsequently, each carcass code CC is thinned in the binarized extracted image (SA8). This thinning process is performed using, for example, a well-known contraction process. As a result, each carcass code CC is thinned to a line that matches the center line. It is also possible to perform step SA9 and subsequent steps without performing step SA8.

  Subsequently, a plurality of inspection lines SL extending in a direction orthogonal to each carcass code CC is added to the extracted image subjected to the thinning process (SA9, see FIG. 12). The inspection lines SL are arranged at intervals in the image width direction and are linear. Each inspection line SL has 0 gradation (black). Note that one inspection line SL can be added to the extracted image instead of the plurality of inspection lines SL.

  Subsequently, the extracted image that has been thinned in step SA8 is subtracted from the image of each inspection line SL. Thereby, an image of each inspection line SL in which the range intersecting with each carcass code CC is differentiated is obtained (SA10, see FIG. 13).

  Subsequently, an average value of the lengths of the divided inspection lines SL1 formed by dividing the inspection lines SL by calculating the difference between the ranges intersecting with the carcass codes CC is calculated (SA11). If there is a division inspection line SL1 having a length greater than or equal to a predetermined magnification (for example, 1.5 times) with respect to the value, it is determined that an open code has occurred in the tire T that has captured the transmitted X-ray image (SA12). . When it is determined in step SA12 that an open code is generated (SA13), the display unit 31b displays the image before contrast enhancement in step SA2 and each divided inspection line SL1 and the corresponding divided inspection line. A display process for displaying the line SL1 prominently with respect to the other divided inspection line SL1 is performed, and a storage process for storing the measurement date and time, the type of the measured tire T, the determination result, and the like in the storage unit 31c is performed ( SA14). If it is not determined in step SA12 that there is no division inspection line SL1 that is greater than or equal to the predetermined value with respect to the average value and an open code has occurred (SA13), the measurement date and time, the type of the measured tire T, determination in the storage unit 31c A storage process for storing the result and the like is performed (SA15).

  Next, operation | movement of the control part 32a of the 2nd control apparatus 32 is demonstrated, referring the flowchart shown in FIG. The operation of the control unit 33a of the third control device 33 is the same as the operation of the control unit 32a. Here, the image of one turn of the tire T transmitted to the control unit 32a of the second control device 32 is taken from the outside in the width direction of the tire T, and a carcass member is configured on the center side in the width direction of the image. A plurality of carcass cords CC made of metal are imaged, and each carcass cord CC is disposed so as to extend in the image width direction and is spaced from each other in the vertical direction of the image (see FIG. 15). Further, the bead core B is imaged on the other side in the width direction of the image, and a plurality of metal reinforcing cords RC constituting the reinforcing member are imaged in the vicinity of the bead core B. The reinforcing cords RC are inclined at a predetermined angle with respect to the width direction of the image, and are arranged at intervals in the vertical direction of the image. Further, a plurality of metal belt cords BC constituting each belt member are imaged on one side in the width direction of the image, and each belt cord BC is inclined at a predetermined angle with respect to the width direction of the image, and images They are arranged at intervals in the vertical direction. For example, when a background is captured in the image transmitted from the side camera 22, the image of the background alone is subjected to differential processing from the transmitted image, for example, in the image transmitted from the side camera 22. It is preferable to remove other than the belt cords BC, the carcass cords CC, the reinforcing cords RC, and the bead cores B.

  First, when an image for one round of the tire T is transmitted from the side camera 22 to the control unit 32a of the second control device 32 (SB1), the contrast is enhanced similarly to step SA2 of the control unit 31a (SB2). . Thereby, each belt cord BC, each carcass cord CC, each reinforcement cord RC, and bead core B in the image are clarified.

  Subsequently, the component in the vertical direction of the image is emphasized as in step SA3 of the control unit 31a (SB3). Thereby, each belt cord BC, each reinforcement cord RC, and bead core B in the image are emphasized, and each carcass cord CC is thinned or removed.

  Subsequently, the contrast is enhanced similarly to step SA4 of the control unit 31a (SB4). Thereby, each belt cord BC, each reinforcement cord RC, and bead core B in the image are clarified.

  Subsequently, the area is determined in the same manner as Step SA5 of the control unit 31a (SB5). This region determination is performed, for example, by appropriately performing shift processing and addition processing in the vertical direction of the image, and after filling the region where the components emphasized in step SB3 are collected (see FIG. 16), for example, the Prewitt filter and the Sobel filter By performing edge emphasis processing using, the outline OL of the area having the largest area and the area having the next largest area among the areas where the components emphasized in step SB3 are gathered is created (FIG. 17). reference). In this case, the inside of the two contour lines OL is a definite region where the components emphasized in step SB3 are gathered. Note that by performing expansion processing instead of the shift processing and addition processing, it is also possible to fill the region where the components emphasized in step SB3 are gathered. It is also possible to determine the region based on an average density per unit area (for example, a range of several pixels × several pixels).

  Subsequently, only a region other than the fixed region surrounded by each contour line OL is extracted from the image before the contrast is enhanced in step SB2 (SB6). Here, if images other than the belt cords BC, the carcass cords CC, the reinforcing cords RC, and the bead cores B are not captured in the image before enhancing the contrast, only the range outside the contour line OL is extracted. The extracted image is obtained by extracting a region where each carcass code CC is imaged (see FIG. 18). Note that it is also possible to create an extracted image from the image in which the contrast is enhanced in step SB2 and other images.

  Subsequently, similarly to SA7 to SA15 of the control unit 31a, binarization processing (SB7), thinning processing (SB8), addition of a plurality of inspection lines (SB9), and each carcass code CC from each inspection line A step of obtaining an image in which the intersecting range is differentiated (SB10), calculation of an average value of the lengths of the respective division inspection lines (SB11), determination of whether or not an open code is generated (SB12), and an open code is generated If the open code is not generated (SB13), the display process and the storage process (SB14) are performed (SB13), and the open process (SB13) is performed (SB15).

  As described above, according to the present embodiment, the region where the carcass code CC is imaged is extracted from the image captured by the imaging device 20, and the extracted image is binarized and binarized. And adding a plurality of inspection lines SL extending in a direction substantially orthogonal to the carcass code CC to obtain an image of each inspection line SL in which the range intersecting the carcass code CC is different, and the carcass code CC An average value of the lengths of a plurality of divided inspection lines SL1 formed by dividing each inspection line SL by the difference between the intersecting ranges is calculated, and a division having a length equal to or greater than a predetermined magnification is calculated with respect to the average value. If the inspection line SL1 is present, it is determined that an open code is generated in the tire T that has captured the transmitted X-ray image. If the open code is generated is wider than the value, dividing the inspection lines SL1 predetermined ratio or more in length is generated with respect to the average value, it is determined that the open code is generated. Therefore, by appropriately setting the predetermined magnification according to the type of tire T, it is possible to accurately determine the presence or absence of an open code. In addition, it is possible to make a determination automatically without visual observation, and it is not necessary to create reference data for each type of tire T, which is extremely advantageous in reducing the time required for inspection.

  In addition, the images picked up by the cameras 21 and 22 are subjected to the above-described image processing by the control units 31a, 32a, and 33a of the control devices 31, 32, and 33, and the presence or absence of an open code is automatically inspected. Therefore, the inspection speed can be improved as compared with the case where the inspector visually confirms the images captured by the cameras 21 and 22 and inspects for the presence of the open code.

  Further, the contrast of the image captured by the imaging device 20 is enhanced (steps SA2 and SB2), and the component in the direction substantially orthogonal to the direction in which the carcass code CC extends in the image with enhanced contrast is enhanced (step SA3). , SB3), a region where the components emphasized in steps SA3 and SB3 are gathered is determined (steps SA5 and SB5), and a region other than the determined fixed region is extracted from the image captured by the imaging device 20. Thus, the region where the carcass code CC is captured is extracted from the image captured by the imaging device 20 (steps SA6 and SB6). Thereby, even when the area where each carcass code CC is imaged changes according to the type of tire T, the area where the carcass code CC is imaged can be surely automatically recognized in the image captured by the imaging device 20. it can. Therefore, when the inspection line SL is added in steps SA9 and SB9, the inspection line SL can be surely added to the area where the carcass code CC is imaged, and the presence / absence of an open code can be accurately determined. Is very advantageous.

  In addition, since the dynamic binarization process is performed in steps SA7 and SB7, even if the image captured by the image capturing apparatus 20 is bright or dark due to a difference in light amount or a member thickness of the tire T, it is irrespective of light or dark. In addition, the carcass code CC can be made clear, which is extremely advantageous in accurately determining the presence or absence of an open code.

  Since the carcass code CC in the image binarized at steps SA7 and SB7 is thinned at steps SA8 and SB8 before the inspection line SL is added at steps SA9 and SB9, Regardless of the thickness of the carcass code CC, the length of each of the divided inspection lines SL1 can be made substantially equal to the interval between the carcass codes CC, which is extremely advantageous for accurately determining the presence or absence of an open code.

  In the present embodiment, before performing steps SA7 to SA15 and steps SB7 to SB15, regions SA2 to SA6 and steps SB2 to SB6 are performed, and the area where the carcass code CC is captured from the image captured by the imaging device 20 To extract. On the other hand, even when steps SA2 to SA6 and steps SB2 to SB6 are omitted, and steps SA7 to SA15 and steps SB7 to SB15 are directly performed on the image captured by the imaging device 20, in steps SA9 and SB9, By adding each inspection line SL to the range where each carcass code CC is imaged, it is possible to accurately determine the presence or absence of an open code as in the case of performing steps SA2 to SA6 and steps SB2 to SB6.

  In this embodiment, the region where the components emphasized in steps SA3 and SB3 are gathered is determined in steps SA5 and SB5, and only regions other than the determined region are extracted in steps SA6 and SB6. Indicated. On the other hand, it is also possible to determine a region other than the region where the components emphasized in steps SA3 and SB3 are gathered in steps SA5 and SB5, and extract only the confirmed region in steps SA6 and SB6. Even in this case, a range equivalent to this embodiment is extracted.

  In the present embodiment, each inspection line SL is added so as to extend in a direction substantially orthogonal to each carcass cord CC. On the other hand, even if each inspection line SL and each carcass cord CC are not substantially orthogonal, if each inspection line SL is added so as to extend in a direction intersecting with each carcass code CC, this embodiment It is possible to achieve the same effect as that.

  In the present embodiment, the control units 31a, 32a, and 33a of the control devices 31, 32, and 33 perform image processing of an image for one round of the tire T, and determine the presence or absence of an open code based on the image processed image. Showed what to do. On the other hand, image processing of an image obtained by capturing a part of the tire T is performed by the control units 31a, 32a, and 33a of the control devices 31, 32, and 33, and whether or not there is an open code based on the image that has been subjected to the image processing. Can also be determined.

  In this embodiment, steps SA1 to SA15 are performed by the control unit 31a of the first control device 31, and steps SB1 to SB15 are performed by the control units 32a and 33a of the second control device 32 and the third control device 33. However, it is also possible to perform any step among steps SA1 to SA15 and SB1 to SB15 by operating the control units 31a, 32a, and 33a by an inspector, for example.

Schematic of an irradiation apparatus and an imaging apparatus showing an embodiment of the present invention Block diagram of tire inspection equipment The flowchart which shows operation | movement of the control part of a 1st controller. Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device Schematic of an image processed by the control unit of the first control device The flowchart which shows operation | movement of the control part of a 2nd control apparatus. Schematic of the image processed by the control unit of the second control device Schematic of the image processed by the control unit of the second control device Schematic of the image processed by the control unit of the second control device Schematic of the image processed by the control unit of the second control device

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Irradiation device, 20 ... Imaging device, 21 ... Upper camera, 22 ... Side camera, 30 ... Inspection apparatus main body, 31 ... 1st control apparatus, 31a ... Control part, 31b ... Display part, 31c ... Storage part, 32 ... second control device, 32a ... control unit, 32b ... display unit, 32c ... storage unit, 33 ... third control device, 33a ... control unit, 33b ... display unit, 33c ... storage unit, CC ... carcass code, BC ... Belt cord, RC ... reinforcing cord, T ... tyre, B ... bead core.

Claims (12)

An electromagnetic wave such as X-rays or γ rays is irradiated toward the tire from the inner peripheral surface side of the tire, and a transmitted electromagnetic wave image transmitted through the tire is imaged by an imaging device disposed on the outer peripheral surface side of the tire. In the tire inspection method for inspecting whether or not an open cord in which the carcass cord interval is partially widened is generated in the tire imaged of
An extraction step of extracting a region where the carcass code is imaged from an image captured by the imaging device;
A binarization step for binarizing the extracted image extracted by the extraction step;
An inspection line addition step of adding at least one inspection line extending in a direction crossing the carcass code in the image binarized by the binarization step;
A difference step for obtaining an image of the inspection line in which the range intersecting the carcass code is differentiated;
An average value calculating step for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line by the difference in the range intersecting the carcass code;
A determination step of determining that an open code is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than or equal to a predetermined magnification with respect to the average value calculated by the average value calculation step. A tire inspection method characterized by the above. In the extraction step, an enhancement step for enhancing the contrast of the image captured by the imaging device, and an orthogonal component enhancement for enhancing a component in a direction substantially orthogonal to the direction in which the carcass code extends in the image whose contrast is enhanced by the enhancement step. Extracting a region other than the determined region determined by the region determining step from the step, a region determining step for determining a region where the components emphasized by the orthogonal component enhancing step are gathered, and an image captured by the imaging device The tire inspection method according to claim 1, further comprising: an extraction step outside the fixed region that extracts a region where the carcass code is captured from an image captured by the imaging device. In the extraction step, an enhancement step for enhancing the contrast of the image captured by the imaging device, and an orthogonal component enhancement for enhancing a component in a direction substantially orthogonal to the direction in which the carcass code extends in the image whose contrast is enhanced by the enhancement step. A step, a region determination step for determining a region other than a region where the components emphasized by the orthogonal component enhancement step are gathered, and a fixed region determined by the region determination step is extracted from an image captured by the imaging device The method for inspecting a tire according to claim 1, further comprising: a step of extracting a region in which the carcass code is captured from an image captured by the imaging device. An electromagnetic wave such as X-rays or γ rays is irradiated toward the tire from the inner peripheral surface side of the tire, and a transmitted electromagnetic wave image transmitted through the tire is imaged by an imaging device disposed on the outer peripheral surface side of the tire. In the tire inspection method for inspecting whether or not an open cord in which the carcass cord interval is partially widened is generated in the tire imaged of
A binarization step for binarizing the image captured by the imaging device;
An inspection line addition step of adding at least one inspection line extending in a direction intersecting the carcass code in a range in which the carcass code in the image binarized by the binarization step is captured;
A difference step for obtaining an image of the inspection line in which the range intersecting the carcass code is differentiated;
An average value calculating step for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line by the difference in the range intersecting the carcass code;
A determination step of determining that an open code is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than or equal to a predetermined magnification with respect to the average value calculated by the average value calculation step. A tire inspection method characterized by the above. The tire inspection method according to claim 1, 2, 3, or 4, wherein the binarization step is configured to perform dynamic binarization processing. The thinning step of thinning the carcass code in the image binarized by the binarization step, which is performed before the inspection line addition step. 4. The tire inspection method according to 4 or 5. An irradiation device that irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire, and an imaging device that is disposed on the outer peripheral surface side of the tire and picks up a transmitted electromagnetic wave image transmitted through the tire In the tire inspection apparatus for inspecting whether or not an open cord in which the interval of the carcass cord is partially widened occurs in the tire that has captured the transmitted electromagnetic wave image,
Extracting means for extracting a region where the carcass code is imaged from an image captured by the imaging device;
Binarization means for binarizing the extracted image extracted by the extraction means;
Inspection line adding means for adding at least one inspection line extending in a direction intersecting the carcass code in the image binarized by the binarization means;
Differential means for obtaining an image of the inspection line in which the range intersecting the carcass code is differential;
An average value calculating means for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line by the difference in the range intersecting the carcass code;
A determination unit that determines that an open code is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than a predetermined magnification with respect to the average value calculated by the average value calculation unit; A tire inspection device characterized by that. The extraction unit includes an enhancement unit that enhances the contrast of an image captured by the imaging apparatus, and an orthogonal component enhancement that enhances a component in a direction substantially orthogonal to the direction in which the carcass code extends in the image in which the contrast is enhanced by the enhancement unit. A region determining unit that determines a region in which the components emphasized by the orthogonal component enhancing unit are gathered; and an area other than the determined region determined by the region determining unit is extracted from an image captured by the imaging device. The tire inspection apparatus according to claim 7, further comprising: a non-determined region extraction unit that extracts a region where the carcass code is captured from an image captured by the imaging device. The extraction unit includes an enhancement unit that enhances the contrast of an image captured by the imaging apparatus, and an orthogonal component enhancement that enhances a component in a direction substantially orthogonal to the direction in which the carcass code extends in the image in which the contrast is enhanced by the enhancement unit. Means for determining a region other than the region in which the components emphasized by the orthogonal component emphasizing unit are gathered, and extracting the determined region determined by the region determining unit from the image captured by the imaging device The tire inspection device according to claim 7, further comprising: an in-determined region extraction unit configured to extract a region in which the carcass code is captured from an image captured by the imaging device. An irradiation device that irradiates the tire with electromagnetic waves such as X-rays and γ rays from the inner peripheral surface side of the tire, and an imaging device that is disposed on the outer peripheral surface side of the tire and picks up a transmitted electromagnetic wave image transmitted through the tire In the tire inspection apparatus for inspecting whether or not an open cord in which the interval of the carcass cord is partially widened occurs in the tire that has captured the transmitted electromagnetic wave image,
Binarization means for binarizing the image captured by the imaging device;
Inspection line adding means for adding at least one inspection line extending in a direction intersecting the carcass code in a range in which the carcass code in the image binarized by the binarization means is captured;
Differential means for obtaining an image of the inspection line in which the range intersecting the carcass code is differential;
An average value calculating means for calculating an average value of the lengths of the plurality of divided inspection lines formed by dividing the inspection line by the difference in the range intersecting the carcass code;
A determination unit that determines that an open code is generated in a tire that has captured a transmitted electromagnetic wave image when there is a division inspection line having a length greater than a predetermined magnification with respect to the average value calculated by the average value calculation unit; A tire inspection device characterized by that. The tire inspection apparatus according to claim 7, 8, 9, or 10, wherein the binarization means is configured to perform dynamic binarization processing. It is characterized by comprising thinning means for thinning the carcass code in the image binarized by the binarizing means, which is performed before adding the inspection line by the inspection line adding means. The tire inspection device according to claim 7, 8, 9, 10, or 11.

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