JP2007147661A - X-ray inspection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inspect as to whether an object to be inspected has a size determined to some degree by measuring the size of the object to be inspected. <P>SOLUTION: A width computation means 19a takes on a value, acquired by multiplying the distance between elements of an X-ray detector 10 by the ratio between the distance Y1 from an X-ray generator 9 to the surface of the object to be inspected W, and the distance Y2 from the X-ray generator 9 to the X-ray detector 10 as a unit size in the transfer width direction Y to concentration data and computes various width sizes of the object to be inspected W in the transfer width direction Y, on the basis of the unit size in the transfer width direction Y. A length computation means 19b takes on a value acquired by dividing a transfer speed by a repetition rate as a unit size in a transfer direction X to concentration data and computes various length sizes of the content of the object to be inspected W in the transfer direction X, on the basis of the unit size in the transfer direction X. When the external size of the object to be inspected W, acquired by these computations lies outside the allowable range of external size set from a setting input means 15, the object to be inspected W is decided as being a size defect. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an X-ray inspection apparatus for inspecting the presence or absence of foreign matter in an object to be inspected, the presence or absence of a seal defect, the presence or absence of a missing item, etc. from the amount of X-ray transmission when X-rays are exposed. The present invention relates to an X-ray inspection apparatus having a function of measuring the dimensions of an object.

  For example, an X-ray inspection apparatus using X-rays as disclosed in Patent Document 1 is known as an apparatus for inspecting the presence or absence of foreign matter in an object to be inspected conveyed on a product line. The X-ray inspection apparatus exposes X-rays to each type of inspection object (for example, raw meat, fish, processed food, medicine, etc.) that are sequentially transported on the transport path, and the amount of transmitted X-rays transmitted. Therefore, it is inspected whether or not foreign matter such as metal, glass, stone and bone is mixed in the inspection object.

  In addition, in this type of X-ray inspection apparatus, for example, in the case of an inspected object whose contents are contained in a package and sealed, such as a poultice, in addition to the inspection for the presence or absence of foreign matter, the contents to the seal part An inspection is also performed for the presence of defective seals due to biting of objects. In this case, the width of the seal part of the object to be inspected is set in advance, and the X-ray transmission data when the X-ray is exposed to the object to be inspected shows a lightness level equivalent to the content in the area of the seal part. The presence or absence of a seal failure is inspected based on whether or not X-ray transmission data exists.

Further, in this type of X-ray inspection apparatus, in the case of an object to be inspected whose contents are accommodated in a container such as a tray or a box, a mask area in which an area other than the position where the contents should originally exist is masked in advance. The content is set based on whether or not X-ray transmission data indicating a lightness level equivalent to the content exists in the mask area from the X-ray transmission data when the inspection object is exposed to X-rays. We are inspecting for missing items.
JP 2003-139723 A

  By the way, in the inspection of the inspection object conveyed by the product line described above, there is an inspection that requires dimension measurement such as the size, shape, and arrangement of the contents. For this reason, as one conventional technique, a single dimension of an object to be inspected is inspected using a dimension measuring apparatus separate from the X-ray inspection apparatus. However, in this type of dimension measuring apparatus, when the contents are inspected in a non-transparent package, the contents cannot be measured because the contents in the package cannot be seen from the outside. There was a problem.

  As another method, a combination of a dimension measuring apparatus and an X-ray inspection apparatus for inspecting the dimension of an inspection object can be considered. However, in the combined inspection by the dimension measuring apparatus and the X-ray inspection apparatus, the inspection object tilts while the inspection object is transported from the dimension measuring apparatus arranged on the conveyance path to the X-ray inspection apparatus. There is a problem that the dimension information measured by the measuring apparatus is not accurately reflected in the X-ray inspection apparatus.

  Further, when a retort food in which a plurality of contents (for example, croquettes, dumplings, bake, etc.) are arranged on a tray and packaged in a film-like non-transparent package is used as an object to be inspected, FIG. As shown in FIG. 5, the vertical and horizontal sizes (L1, H1) of the contents Wa are determined to some extent for good products. However, as shown in FIG. 5B, the vertical and horizontal sizes (L1, H1) of the content Wa change even when the shape of the content Wa is collapsed even if the area is the same as that of the non-defective product. It is necessary to sort out this inspection object as a defective product. However, the conventional X-ray inspection apparatuses including the above-mentioned Patent Document 1 do not have a function of measuring the dimensions of the inspection object W including the contents Wa, so that as shown in FIGS. Even when the area of the X-ray transmission data of the light and shade level indicating the content Wa when the object W is exposed to X-rays is approximately the same, the shape of the content Wa collapses and the dimensions change. There was also a problem that it was not possible to distinguish between good and defective products.

  Therefore, the present invention has been made in view of the above problems, and an X-ray inspection apparatus capable of measuring whether or not an inspection object has a certain size by measuring the dimension of the inspection object. The purpose is to provide.

In order to achieve the above object, an X-ray inspection apparatus according to claim 1 of the present invention applies X-rays to an object to be inspected W that is transported on a transport path in a state where the contents Wa are contained in a package. An X-ray generator 9 to be exposed;
X-rays passing through the inspection object are detected by a plurality of elements arranged linearly in the conveyance width direction Y orthogonal to the plane in the conveyance direction X of the inspection object, and density data of the detection result is used as the element. An X-ray detector 10 that sequentially outputs up to the number of elements each time and repeats the sequential output in accordance with the conveyance speed of the inspection object;
In an X-ray inspection apparatus that inspects the inspection object based on density data output from the X-ray detector,
Setting input means (15) for setting dimensional information including the height of the inspection object and an outer dimension of the content including an allowable range of a non-defective sample of the inspection object;
Concentration data output from the X-ray detector, distance between elements of the X-ray detector, transport speed of the inspection object, repetition speed of sequential output of the density data, transport path from the X-ray generator The distance Y1 to the inspected object obtained by subtracting the height of the inspected object set by the setting input means from the distance to the transfer surface, the distance from the X-ray generator to the X-ray detector Dimension calculation means 19 for calculating the dimensions of the contents of the inspection object in the transport direction and the transport width direction based on Y2,
Discriminating means (20) for discriminating the inspection object as a defective dimension when the external dimension of the contents of the inspection object calculated by the dimension calculation means is outside the allowable range of the external dimension set by the setting input means. ).

The X-ray inspection apparatus according to claim 2 generates X-rays by irradiating an object to be inspected (W) transported on a transport path in a state where the contents (Wa) are accommodated in a package. Vessel (9),
X-rays transmitted through the inspection object are detected by a plurality of elements arranged linearly in the conveyance width direction (Y) orthogonal to the plane of the inspection object conveyance direction (X), and the detection result An X-ray detector (10) that sequentially outputs density data for each element up to the number of the plurality of elements, and repeats the sequential output corresponding to the conveyance speed of the inspection object;
In an X-ray inspection apparatus that inspects the inspection object based on density data output from the X-ray detector,
Setting input means 15 for setting dimensional information including the height of the inspection object, and an area and an external dimension of the content including an allowable range of a non-defective sample of the inspection object;
Concentration data output from the X-ray detector, distance between elements of the X-ray detector, transport speed of the inspection object, repetition speed of sequential output of the density data, transport path from the X-ray generator The distance Y1 to the inspected object obtained by subtracting the height of the inspected object set by the setting input means from the distance to the transport surface, and the distance from the X-ray generator to the X-ray detector Dimension calculation means (19) for calculating the dimensions of the contents of the inspection object in the transport direction and the transport width direction based on Y2,
Area calculating means (18) for calculating the area of the contents of the inspection object based on the density data output from the X-ray detector;
The area calculated by the area calculating means, the outer dimensions of the contents of the inspection object calculated by the dimension calculating means, the area set by the setting input means, and the outer dimensions set by the setting input means And a discriminating means (20) for discriminating the shape defect of the inspection object.

The X-ray inspection apparatus according to claim 3 is the X-ray inspection apparatus according to claim 1 or 2,
The dimension calculation means 19 is a ratio Y1 between the distance Y1 from the X-ray generator 9 to the inspection object W and the distance Y2 from the X-ray generator to the X-ray detector 10 as the distance between the elements. Width calculating means 19a for calculating the dimension in the transport width direction Y based on the unit dimension for the density data obtained by multiplying / Y2.
The value of the repetition speed is adjusted so that the unit dimension in the conveyance direction X with respect to the density data obtained by dividing the conveyance speed by the repetition speed is equal to the unit dimension in the width direction calculated from the width calculation means. And length calculation means 19b for calculating the dimension in the transport direction based on the unit dimension in the transport direction.

  According to the present invention, it is possible to measure the external dimensions of the contents of the inspected object without specially requiring a size check machine such as a conventional dimension measuring apparatus, and to check whether there is a dimension defect or shape defect of the inspected object. Can be inspected. Moreover, if the repetition speed is determined so that the unit dimension in the transport direction X substantially matches the unit dimension in the transport width direction Y and the dimension in the transport direction X is calculated, the vertical ratio of the image of the inspection object W becomes substantially equal. The displayed image can be reproduced more faithfully.

  1 is a schematic configuration diagram of an X-ray inspection apparatus according to the present invention, FIG. 2 is a block configuration diagram of the X-ray inspection apparatus according to the present invention, and FIG. 3 is transported on a belt surface of a transport section in the X-ray inspection apparatus. FIG. 4 is a front view showing the positional relationship between the X-ray generator, the inspection object, and the belt surface of the transport unit when X-rays are exposed to the inspection object in the X-ray inspection apparatus. .

  The X-ray inspection apparatus 1 of the present example is provided in a part of the conveyance path of the product line, and performs dimension inspection, shape inspection, and foreign matter in the inspection object W which are sequentially conveyed at a predetermined interval. Various inspections such as presence / absence of contamination, presence / absence of a seal portion due to biting of contents, and presence / absence of missing parts due to missing contents are performed.

  In the X-ray inspection apparatus 1 shown in FIG. 1, a conveyance unit 2 and a foreign matter detection unit 3 are provided in the apparatus main body 4, and a display 5 is provided in the upper front portion of the apparatus main body 4.

  The conveyance unit 2 sequentially conveys the same type of inspection object W (for example, the contents are contained in a non-transparent package and at least a part thereof is sealed) W at predetermined intervals. This conveyance part 2 can be comprised with the belt conveyor arrange | positioned horizontally with respect to the apparatus main body 4, for example. The conveyance unit 2 directs the inspection object W carried in from the carry-in port 7 at a constant conveyance speed set in advance by driving of the drive motor 6 shown in FIG. 1 toward the carry-out port 8 (carrying direction X in the drawing). The belt surface 2a as a conveyance surface is conveyed.

  The detection unit 3 detects X-rays that are transmitted through the inspection object W by exposing X-rays to the inspection object W that is sequentially transported in the transport path. An X-ray generator 9 provided at a predetermined height apart and an X-ray detector 10 provided opposite to the X-ray generator 9 in the transport unit 2 are configured.

  An X-ray generator 9 as an X-ray generation source has a configuration in which a cylindrical X-ray tube 12 provided in a metal box 11 is immersed in insulating oil (not shown), and from the cathode of the X-ray tube 12. X-rays are generated by irradiating the anode target with the electron beam. The X-ray tube 12 is provided in a direction (Y direction) whose longitudinal direction is orthogonal to the conveyance direction X of the inspection object W. The X-rays generated by the X-ray tube 12 are exposed to the lower X-ray detector 10 in the form of a substantially triangular screen by a slit (not shown) along the longitudinal direction.

  The X-ray detector 10 has a plurality of elements arranged in a straight line in the Y direction perpendicular to the transport direction X on the plane of the transport direction X of the object W to be transported, and is aligned in a line. And a plurality of elements including a scintillator provided on a line-shaped photodiode. In this X-ray detector 10, X-rays that pass through the inspection object W are detected by a plurality of elements arranged linearly in a direction Y that is orthogonal to the plane of the inspection object W in the transport direction X, and this detection is performed. Concentration data based on the result is sequentially output up to the number of elements with a plurality of elements as one line for each element, and the sequential output from one line is repeated as the object W is conveyed.

  As shown in FIG. 2, position detection means 13 for detecting the passage of the inspection object W is provided on the carry-in entrance 7 side of the transport unit 2. The position detecting means 13 is configured by a photosensor including a pair of light projecting and receiving devices provided on the entrance side of the belt conveyor as the transport unit 2. With this configuration, an ON signal is input from the position detection unit 13 to the signal processing unit 14 as a timing signal while the inspection object W passes in front of the photosensor.

  In the X-ray detector 10 having such a configuration, X-rays are exposed from the X-ray generator 9 to the inspection object W transported on the transport unit 2. Then, the X-ray transmitted through the inspection object W with the X-ray exposure to the inspection object W is received by the scintillator and converted into light. The light converted by the scintillator is received by a photodiode disposed under the scintillator. Each photodiode converts the received light into an electrical signal and outputs it. The X-ray detector 10 outputs an electric signal having a level corresponding to the intensity of the received X-ray to the signal processing means 14.

  In FIG. 2, the signal processing means 14 includes a CPU, a memory, and the like, and after a predetermined time using the ON signal when the position detection means 13 detects the inspection object W as a timing signal, the X-ray detector 10. Various signal processing is performed by taking in electrical signals from

  As shown in FIG. 2, the signal processing unit 14 includes a setting input unit 15, a storage unit (data memory) 16, an outer region extraction unit 17, an area calculation unit 18, a dimension calculation unit 19, and a determination unit 20.

  The setting input means 15 is composed of a plurality of keys and switches operated by the user to give various settings and instructions regarding the size inspection, shape inspection, foreign matter inspection, seal defect inspection, missing part inspection and display of the inspection object W. Is done. More specifically, the setting input means 15 looks at a good product sample in advance, and the outer dimensions and area of the content Wa of the inspection object W including the allowable range of the good product sample, the width dimension of the seal portion of the inspection object W (for example, If the outer shape is rectangular, it is possible to appropriately input numerical values such as the dimension information of the inspection area in which the inspection object W is inspected, and the like. Further, the setting input means 15 inputs the number of locations having the seal portion, or designates the type of the inspection object W, thereby specifying the width dimension of the seal portion corresponding to the type of the inspection object W stored in advance. Various dimension information regarding the seal portion such as setting can also be input.

  Further, from the setting input means 15, in addition to the above settings, the conveyance speed of the conveyance unit 2, the height of the inspection object W, the distance from the X-ray generator 9 to the conveyance surface of the inspection object W, the X-ray generator 9. Setting of distance Y2 from 9 to X-ray detector 10, detection limit value serving as reference for determining presence / absence of foreign matter in inspection object W, detection limit serving as reference for determining content Wa It is possible to set a value, a detection limit value serving as a reference for determining the presence or absence of a seal failure in the seal portion of the inspection object W, and the like. In addition, the setting input means 15 can set a detection limit value that serves as a reference for determining the presence or absence of foreign matter in the inspected object W and the presence or absence of missing contents when performing a plurality of inspections. It has become. These detection limit values are appropriately set according to the type of the inspection object W, the type of foreign matter to be detected, and the like.

  The storage means 16 stores X-ray transmission data for each inspection object W. This X-ray transmission data is obtained by A / D converting an electric signal from the X-ray detector 10 by an A / D converter (not shown). More specifically, every time one inspection object W is inspected, for example, 640 pieces of X-ray transmission data per line (Y direction) of the X-ray detector 10 are conveyed to the storage means 16 at least. A predetermined number of lines (480 lines) corresponding to the length of the inspection object W in the transport direction (corresponding to a detection period from the front end to the rear end) is stored.

  The contour area extraction unit 17 obtains density data based on the entire grayscale image (entire image for each inspection object W including the belt surface 2a of the transport unit 2) from the X-ray transmission data (density data) stored in the storage unit 16. A contour region S1 indicating the inner area is extracted from the contour of the inspection object W in the created density data of the entire image. More specifically, the outer shape region extracting unit 17 obtains the entire histogram from the gray level of the X-ray transmission data stored in the storage unit 16. Then, the density data D1 of the inspection object W and the density data D2 other than the inspection object W (actually, the belt surface of the transport unit 2) are divided into binary values from the obtained entire histogram. For example, the density data D1 of the inspection object is set to 255, and the density data D2 other than the inspection object is set to 0. Then, binarized inspection object density data D1 is extracted as an outer region.

  The area calculating unit 18 detects the X-ray transmission data (detected by the X-ray detector 10 and stored in the storage unit 16 based on the detection limit value for determining the content Wa input from the setting input unit 15 in advance. The area of the portion corresponding to the content Wa of the inspection object W is calculated from the density data), and the result is input to the discrimination means 20. That is, in the area calculation means 18, a unit area based on one density data is set in advance, and among the density data stored in the storage means 16, the total value of the density data exceeding the detection limit value is obtained. Calculated as area.

  The unit area of one density data is a value obtained by multiplying the unit dimension in the transport direction X by the unit dimension in the transport width direction Y, and the unit dimension in the transport direction X and the unit dimension in the transport width direction Y are It is preferable to adjust the scanning speed (repetition speed) in advance so that they are equal. Thereby, the pitch of the unit dimension in the conveyance direction X and the pitch of the unit dimension in the conveyance width direction Y coincide with each other, and the unit area of the density data becomes a square.

  The size calculation means 19 is output from the X-ray detector 10 and stored in the storage means 16, the distance between the elements of the X-ray detector 10, the conveyance speed of the inspection object W, and the X-ray detector 10. The inspection object is based on the repetition speed of the sequential output of the concentration data to be output, the distance Y1 from the X-ray generator 9 to the surface of the inspection object W, and the distance Y2 from the X-ray generator 9 to the X-ray detector 10. Various dimensions of W in the conveyance direction X and the conveyance width direction Y (the outer dimension of the inspection object W, the outer dimension of the contents Wa, and the seal portion region dimension) are calculated. In addition, the dimension calculation unit 19 calculates an inspection region whose size has been corrected based on the dimension information of the inspection region set in advance from the setting input unit 15 with the outer region extracted by the outer region extraction unit 17 as a reference. .

  The dimension calculating unit 19 includes a width calculating unit 19a and a length calculating unit 19b. The width calculation means 19a is configured such that the distance Y1 from the X-ray generator 9 to the surface of the inspection object W and the distance from the X-ray generator 9 to the X-ray detector 10 with respect to the distance between the elements of the X-ray detector 10. A value obtained by multiplying the ratio with Y2 is a unit dimension in the conveyance width direction Y with respect to the density data, and various width dimensions in the conveyance width direction Y of the inspection object W are calculated based on the unit dimension in the conveyance width direction Y. . Specifically, the distance Y1 from the X-ray generator 9 to the surface of the inspection object W = 480 mm, the distance Y2 from the X-ray generator 9 to the X-ray detector (detection element) 10 = 500 mm, the X-ray detector When the element pitch of 10 is 0.4 mm, 0.4 × 480/500 = 0.384 mm is calculated as the unit dimension in the transport width direction Y. Then, based on the unit dimension 0.384 mm in the transport width direction Y, the width dimension in the transport width direction Y of the outer shape of the inspection object W extracted by the outer region extraction means 17 (width H1 in FIGS. 3 to 5). The width dimension in the conveyance width direction Y of the contents Wa calculated by the area calculation unit 18 and the width dimension in the conveyance width direction Y of the seal portion region set from the setting input unit 15 can be calculated. Since the positions of the X-ray generator 9 and the X-ray detector 10 are fixed, the distance Y2 from the X-ray generator 9 to the X-ray detector 10 is a known value. Can be entered. Further, since the distance Y1 from the X-ray generator 9 to the surface of the inspection object W varies depending on the height of the inspection object W, the distance from the X-ray generator 9 to the conveyance surface of the inspection object W (known) And the height of the inspection object W are input from the setting input means 15 and calculated by subtracting the height of the inspection object W from the distance from the X-ray generator 9 to the transport surface of the inspection object W. Is done.

  The length calculation means 19b uses a value obtained by dividing the transport speed by the scan speed (repetition speed: the number of scans per unit time) as a unit dimension in the transport direction X with respect to the density data. Various length dimensions in the conveyance direction X of the inspection object W are calculated. Specifically, when the conveyance speed is set to 400 mm / second, the scan speed (repetition speed) is 400 / 0.384 = 1041 times / from the unit dimension 0.384 mm in the conveyance width direction Y calculated by the width calculation unit 19a. Second, 400/1041 = 0.384 mm obtained by dividing the conveyance speed of 400 mm / second by the scanning speed (repetition speed) of 1041 times / second is calculated as the unit dimension in the conveyance direction X. And the length dimension (length L1 in FIGS. 3 and 5) of the outer shape of the inspection object W extracted by the outer region extraction means 17 based on the unit dimension 0.384 mm in the transport direction X, The length dimension in the conveyance direction X of the content Wa calculated by the area calculation unit 18 and the length dimension in the conveyance direction X of the seal portion region set from the setting input unit 15 can be calculated.

  In this example, after determining the transport speed, the unit dimension in the transport direction X is set to the optimum value for the scan speed (repetition speed) so as to be equal to the unit dimension in the transport width direction calculated from the width calculating unit 19a. Adjust and seek. Thereby, the pitch of the unit dimension of the conveyance direction X and the pitch of the unit dimension of the conveyance width direction Y correspond.

  The discriminating means 20 includes a dimension discriminating means 20a, a shape discriminating means 20b, a foreign matter discriminating means 20c, a seal portion defect discriminating means 20d, and a missing part discriminating means 20e. A selection signal for selecting the inspection object W as a non-defective product or a defective product in accordance with the presence / absence of foreign matter, the presence / absence of a seal portion defect, and the presence / absence of a missing product) is externally output.

  The dimension discriminating means 20a is within an allowable range in which the outer dimension of the inspection object W is compared with the outer dimension of the non-defective sample set in advance from the setting input means 15 based on the various dimension information calculated by the dimension calculating means 19. When there is not, it judges that the to-be-inspected object W has produced dimension abnormality, and outputs the selection signal which shows a dimension defect.

  The shape discriminating means 20b includes the area of the contents Wa of the inspection object W calculated by the area calculation means 18 and the outer dimensions of the contents Wa of the inspection object W calculated by the dimension calculation means 19 and the setting input means 15. Are compared with the outer dimensions of the contents Wa of the inspection object W (including the allowable range), and based on the comparison result, it is determined whether or not the inspection object W is defective in shape. That is, in the shape discriminating means 20b, when the area of the contents Wa of the inspection object W calculated by the area calculation means 18 is outside the allowable range of the area set from the setting input means 15, the inspection object W Is determined to be defective. Further, even when the outer dimension of the content Wa of the inspection object W calculated by the dimension calculation means 19 is outside the allowable range of the outer dimension set from the setting input means 15, the inspection object W is defective in shape. Is determined.

  The foreign matter discriminating means 20c determines whether or not foreign matter is mixed in the inspection area (content effective area) of the inspection object W calculated by the dimension calculating means 19 depending on whether or not there is a portion with a different density level in the inspection area. The presence or absence is determined. That is, when a portion having a higher light and shade level than other portions exists in the inspection area, the portion having the higher light and shade level is determined as a foreign object. More specifically, the foreign matter determination means 20c uses the density level of the X-ray transmission data of the inspection area of the inspection object W calculated by the dimension calculation means 19 and the foreign matter detection limit value preset by the setting input means 15. In comparison, when the X-ray transmission data exceeds the foreign matter detection limit value, it is determined that foreign matter is mixed in the inspection object W, and a selection signal indicating the presence of foreign matter is output. The foreign object detection limit value can be set from the setting input unit 15 as appropriate for each inspection object W according to the contents.

  The seal portion defect determination unit 20d compares the gray level of the image of the inspection area (the seal portion area) of the inspection object W calculated by the size calculation unit 19 with the gray level of the image of the contents of the inspection object W. Thus, the presence / absence of a seal failure is determined, and a selection signal indicating whether the seal is normal or defective is output from the determination result. That is, in this seal portion defect determination means 20d, when there is a gray level equal to or higher than the gray level of the image of the contents of the inspection object W in the inspection region (seal portion region), the inspection object W It is determined that there is a sealing failure, and a selection signal indicating the sealing failure is output. It should be noted that the detection limit value of the defective seal portion can be appropriately set from the setting input means 15 for each inspection object W according to the contents.

  In the inspection area (content area) of the inspection object W calculated by the dimension calculation means 19, the missing item determination means 20e has a lightness level lower than a preset shortage detection limit value (the X-ray transmission amount is large). ), It is determined that, for example, the number of poultices in the non-transparent package is low, and a selection signal indicating that there is a shortage is output. Further, the shortage determination means 20e uses a preset shortage detection mask area, and there is a lightness level equivalent to the content for each inspection area (content area) of the shortage detection mask area. The presence or absence of contents is determined according to the area. It should be noted that the shortage detection limit value and the shortage detection mask area can be set and input from the setting input unit 15 as appropriate for each inspection object W according to the contents.

  Although not shown in the drawings, the signal processing means 14 includes a filter means, and the contents are accommodated as an inspected object W in an extremely thin non-transparent film-like package such as a poultice. The X-ray transmission data of the inspection object W stored in the storage means 16 is subjected to a predetermined filtering process. In this filter processing, for example, a feature extraction filter such as a differential filter (Roberts filter, Prewitt filter, Sobel filter) or a Laplacian filter is used. This enhances the entire image to facilitate edge detection, and further enhances and facilitates extraction of foreign object information and biting information to be detected. Therefore, the foreign matter determination means 20c is not limited to the comparison between the level of the grayscale image and the foreign matter detection limit value, and the foreign matter is compared with the set foreign matter detection limit value for the image in which the foreign matter information after the filter processing is emphasized. The presence or absence of may be judged. Further, the seal portion failure determination unit 20d may determine a seal failure based on the presence or absence of an edge component in the seal portion region after the filtering process.

  On the display screen of the display device 5, an entire gray-scale image (entire image for each inspection object W including the belt surface 2 a of the transport unit 2), an image of the outer area of the inspection object W, and an outer area of the content Wa are displayed. An image, an image of the seal area, an X-ray transmission image obtained by viewing the inspection object W in plan based on the determination result of the determination means 20, the OK / NG determination result, the total number of inspections, the number of non-defective products, NG Inspection results such as the total number are displayed based on a predetermined key operation from the setting input means 15.

  In the X-ray inspection apparatus 1 having the above-described configuration, when performing various inspections, an X-ray transmission image (density data) output from the X-ray detector 10 at the time of X-ray exposure to the inspection object W and each parameter (X-ray) The distance between the elements of the detector 10, the conveyance speed of the inspection object W, the repetition speed (scanning speed) of sequential output of density data, the distance Y1 from the X-ray generator 9 to the inspection object W, the X-ray generator 9 The dimension calculation means 19 determines the external dimensions of the inspection object W, the external dimensions of the contents Wa, the seal area dimensions, etc., including the inspection area of the inspection object W based on the distance Y2) from the X-ray detector 10 to the X-ray detector 10. Calculated.

  At that time, regarding the dimension (width dimension) in the transport width direction Y orthogonal to the transport direction X, an error occurs with respect to the actual length. Normally, in this type of X-ray inspection apparatus, as shown in FIG. 4, the conveyance surface (belt surface) 2a on which the inspection object W is actually conveyed and the X-ray detector 10 are not on the same plane. The line detector 10 is disposed below the conveying surface 2a by a predetermined height. For this reason, when the width H1 of the inspection object W in the conveyance width direction Y is assumed, the width H2 in the conveyance width direction Y in the X-ray transmission image (density data) at the time of X-ray exposure to the inspection object W is the actual inspection object W. Different from the width H1 of the inspection object W. In the example of FIG. 4, the width H2 at the time of X-ray exposure to the inspection object W is larger by 2 × H3 (width H3 on both sides of the inspection object W) than the actual width H1 of the inspection object W. In this example, in order to solve this problem, the distance Y1 from the X-ray generator 9 to the surface of the inspection object W and the distance between the elements of the X-ray detector 10 and the X-ray detector 10 from the X-ray generator 9 are measured. A value obtained by multiplying the ratio with the distance Y2 is used as a unit dimension in the transport width direction Y with respect to the density data, and various dimensions (width dimensions) of the inspection object W in the transport width direction Y based on the unit dimensions in the transport width direction Y. ). In addition, the scanning speed (repetition speed) is adjusted to an optimum value so that the unit dimension in the conveyance direction X is equal to the unit dimension in the conveyance width direction Y, and the preset conveyance speed is the scanning speed (repetition speed). A value obtained by the division is set as a unit dimension in the transport direction X, and various dimensions (length dimensions) of the inspection object W in the transport direction X are calculated based on the unit dimension in the transport direction X.

  Then, each dimension information of the outer dimension of the inspected object W, the outer dimension of the contents Wa, and the seal portion area dimension including the inspection area of the inspected object W calculated by the dimension calculating means 19 is input to the determining means 20. Is done. In addition, information indicating the area of the content Wa of the inspection object W calculated by the area calculation unit 18 is input to the determination unit 20. Then, in the determination means 20 to which various dimension information and area information of the inspection object W are input, various determinations of the inspection object W described below are performed. First, regarding the dimensions of the contents Wa of the inspection object W, the external dimensions of the contents including the allowable range of the non-defective sample of the inspection object W are input from the setting input means 15 in advance. When the outer dimension of the content Wa of the object W calculated by the dimension calculating unit 19 is outside the allowable range of the outer dimension set from the setting input unit 15, the dimension determining unit 20 a Is determined to be defective. For example, if the content Wa having the outer dimensions shown in FIG. 5A is a non-defective product, the outer dimension of the contents Wa is transferred when the inspection object W including the content Wa shown in FIG. (L1, H1) is outside the allowable range, and the inspection object W is determined to be defective.

  With respect to the shape of the content Wa of the inspection object W, the area and outer dimensions of the content including the allowable range of the non-defective sample of the inspection object W are input from the setting input means 15 in advance. The shape discriminating means 20b compares the area calculated by the area calculating means 18, the outer dimensions of the contents Wa of the object W calculated by the dimension calculating means 19, the area set by the setting input means 15 and the outer dimensions. The shape defect of the inspection object W is determined based on the above. That is, when the area calculated by the area calculating unit 18 is outside the allowable range of the area set by the setting input unit 15, the shape determining unit 20b determines that the inspection object W is defective in shape. Further, when the external dimension of the content Wa of the inspection object W calculated by the dimension calculation means 19 is outside the allowable range of the external dimensions set from the setting input means 15, the inspection object W is defective in shape. Is determined. For example, when the content Wa having the shape shown in FIG. 5A is a non-defective product, when the inspection object W including the content Wa shown in FIG. The external dimensions (L1, H1) of the object Wa are out of the allowable range, and the inspection object W is determined as a defective shape. For example, if the content Wa having the shape shown in FIG. 5A is a non-defective product, the outer shape of the content Wa is transferred when the inspection object W including the content Wa shown in FIG. Even if the dimensions (L1, H1) are within the allowable range, the area is out of the allowable range, and the inspection object W is determined to be defective.

  The shape discriminating means 20b discriminates the ratio of the area of the inspection object W calculated by the area calculating means 18 and the dimension calculated by the dimension calculating means 19 and the shape defect set in advance from the setting input means 15. The presence or absence of a shape defect may be determined based on a comparison with a detection limit value. In this case, since only one detection limit value for discriminating a shape defect is required for one inspection object W, setting labor can be saved.

  With respect to the foreign matter mixing inspection of the object W to be inspected, the foreign matter discriminating means 20c depends on whether or not the density level of the density data is different from the others in the inspection area (content effective area) calculated by the dimension calculating means 19. Determine whether foreign matter is mixed.

  With respect to the seal portion defect inspection of the inspection object W, the seal portion defect determination means 20d is equivalent to the density level of the content Wa of the inspection object W in the inspection area (seal portion area) calculated by the dimension calculation means 19. The presence / absence of a sealing failure of the inspection object W is determined based on whether or not the above-described gray level exists.

  Regarding the missing item inspection of the inspected object W, the missing item determination unit 20e calculates the density level in the inspection area (content effective area) calculated by the dimension calculation unit 19 and a preset missing item detection limit value. The presence or absence of a missing item is determined by comparison.

  Thus, according to the X-ray inspection apparatus of this example, the external dimensions of the contents of the inspection object can be measured without requiring a special size check machine such as a conventional dimension measuring apparatus. . In particular, in this example, it is possible to measure the dimensions of the contents of the inspected object using the non-transparent package, and thereby determine whether there is a dimension defect or a shape defect of the contents of the inspected object. Can do. In addition, since the dimension calculation means 19 corrects the dimension error in the transport width direction Y that occurs during X-ray exposure and calculates the dimension in the transport width direction Y, it measures the various dimensions of the inspection object W more accurately. be able to.

  When the dimension of the inspection object W is measured, the conveyance speed is set, and when the dimension in the conveyance width direction Y is calculated by the width calculation unit 19a, the unit in the conveyance width direction Y obtained from the width calculation unit 19a. Since the scanning speed (repetition speed) is obtained so that the dimension and the unit dimension in the transport direction X substantially coincide with each other and the dimension in the transport direction X is calculated by the length calculation means 19b, the vertical ratio of the image of the inspection object W Are substantially equal, and the displayed image can be reproduced more faithfully.

1 is a schematic configuration diagram of an X-ray inspection apparatus according to the present invention. It is a block block diagram of the X-ray inspection apparatus which concerns on this invention. It is a top view of the to-be-inspected object conveyed on the belt surface of the conveyance part in a X-ray inspection apparatus. It is a front view which shows the positional relationship of the X-ray generator, to-be-inspected object, and the belt surface of a conveyance part when X-rays are irradiated to to-be-inspected object in an X-ray inspection apparatus. (A), (b), (c) It is a figure which shows the example of various shapes of the contents of a to-be-inspected object.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray inspection apparatus 9 X-ray generator 10 X-ray detector 15 Setting input means 17 Outline area extraction means 18 Area calculation means 19 Size calculation means 19a Width calculation means 19b Length calculation means 20 Discrimination means W Inspected object Wa Contents object

Claims (3)

An X-ray generator (9) that emits X-rays to the object to be inspected (W) that is transported on the transport path in a state where the contents (Wa) are contained in the package;
X-rays transmitted through the inspection object are detected by a plurality of elements arranged linearly in the conveyance width direction (Y) perpendicular to the plane of the inspection object conveyance direction (X), and the detection result An X-ray detector (10) for sequentially outputting the density data for each element up to the number of the plurality of elements, and repeating the sequential output corresponding to the conveyance speed of the inspection object;
In an X-ray inspection apparatus that inspects the inspection object based on density data output from the X-ray detector,
Setting input means (15) for setting dimensional information including the height of the inspection object and an outer dimension of the content including an allowable range of a non-defective sample of the inspection object;
Concentration data output from the X-ray detector, distance between elements of the X-ray detector, transport speed of the inspection object, repetition speed of sequential output of the density data, transport path from the X-ray generator The distance (Y1) to the inspection object obtained by subtracting the height of the inspection object set by the setting input means from the distance to the transport surface, from the X-ray generator to the X-ray detector Dimensional calculation means (19) for calculating the dimensions of the contents of the inspection object in the transport direction and the transport width direction based on the distance (Y2)
Discriminating means (20) for discriminating the inspection object as a defective dimension when the external dimension of the contents of the inspection object calculated by the dimension calculation means is outside the allowable range of the external dimension set by the setting input means. And an X-ray inspection apparatus. An X-ray generator (9) that emits X-rays to the object to be inspected (W) that is transported on the transport path in a state where the contents (Wa) are contained in the package;
X-rays transmitted through the inspection object are detected by a plurality of elements arranged linearly in the conveyance width direction (Y) perpendicular to the plane of the inspection object conveyance direction (X), and the detection result An X-ray detector (10) for sequentially outputting the density data for each element up to the number of the plurality of elements, and repeating the sequential output corresponding to the conveyance speed of the inspection object;
In an X-ray inspection apparatus that inspects the inspection object based on density data output from the X-ray detector,
Setting input means (15) for setting dimensional information including the height of the inspection object and an area and an external dimension of the content including an allowable range by a non-defective sample of the inspection object;
Concentration data output from the X-ray detector, distance between elements of the X-ray detector, transport speed of the inspection object, repetition speed of sequential output of the density data, transport path from the X-ray generator The distance (Y1) to the inspection object obtained by subtracting the height of the inspection object set by the setting input means from the distance to the transport surface, from the X-ray generator to the X-ray detector Dimensional calculation means (19) for calculating the dimensions of the contents of the inspection object in the transport direction and the transport width direction based on the distance (Y2)
Area calculating means (18) for calculating the area of the contents of the inspection object based on the density data output from the X-ray detector;
The area calculated by the area calculating means, the outer dimensions of the contents of the inspection object calculated by the dimension calculating means, the area set by the setting input means, and the outer dimensions set by the setting input means An X-ray inspection apparatus comprising: a discriminating means (20) for comparing the shape defect of the inspection object in comparison. The dimension calculation means (19) includes a distance (Y1) from the X-ray generator (9) to the object to be inspected (W) and a distance from the X-ray generator to the X-ray detector ( Width calculating means (19a) for calculating the dimension in the transport width direction (Y) based on the unit dimension for the density data obtained by multiplying the ratio (Y1 / Y2) to the distance (Y2) to 10) When,
The value of the repetition speed so that the unit dimension in the conveyance direction (X) with respect to the density data obtained by dividing the conveyance speed by the repetition speed is equal to the unit dimension in the width direction calculated from the width calculation means. The X-ray inspection apparatus according to claim 1, further comprising: a length calculation unit (19 b) for calculating the dimension in the transport direction based on a unit dimension in the transport direction. .

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