JP5860305B2 - X-ray foreign object detection device - Google Patents

Description

  The present invention relates to an X-ray foreign object detection device that detects foreign matter mixed in an object to be inspected such as meat, fish, processed foods, and pharmaceuticals, and more particularly to an X-ray foreign object detection device that employs a TDI sensor as an X-ray detector. Is.

  In general, an X-ray foreign object detection apparatus irradiates X-rays from X-ray generators on various types of inspection objects (for example, meat, fish, processed foods, pharmaceuticals, etc.) that are sequentially conveyed on a conveyance path at predetermined intervals. The inspection object is inspected for foreign substances such as metal, glass, stones, and bones, and a lack of the inspection object, based on the amount of transmitted X-rays.

  Conventionally, in this type of X-ray foreign object detection apparatus, an X-ray inspection unit includes an X-ray generation unit that irradiates an object W to be inspected conveyed on a conveyance path, and a main scanning direction (a conveyance direction on the conveyance surface). The detection element array is composed of a plurality of detection elements arranged in a straight line in the direction perpendicular to the transport direction, and the detection data obtained from each detection element is delayed for each stage of the plurality of detection element arrays. A configuration comprising: an X-ray detector that synthesizes by integration and outputs composite data; and a determination unit that determines the presence or absence of foreign matter in the inspection object W based on the composite data output by the X-ray detector; By doing so, the X-ray detector can detect the X-ray with high sensitivity by synthesizing and outputting the detection data by time delay integration, and reduce the output of the X-ray irradiated by the X-ray generation unit. Is known (for example, special References 1).

JP 2011-242374 A

  However, in the conventional technique described in Patent Document 1, if the position of the X-ray generation unit is shifted from vertically above the center of the X-ray detector, the difference in image due to the difference in detection element position increases. Therefore, there is a problem that the resolution is lowered. In particular, when the position of the X-ray generation unit is shifted in the transport direction, the resolution is significantly reduced.

  On the other hand, a normal X-ray generator has a structure in which a cylindrical X-ray tube as an X-ray source is immersed in insulating oil inside an X-ray unit made of a metal box. Since the position of the X-ray tube at the X-ray tube varies due to manufacturing errors and the like, even when the X-ray unit is accurately placed at a position vertically above the center of the X-ray detector, the X-ray tube is There has been a problem that the position is not necessarily set vertically above the center of the line detector.

  Therefore, the present invention has been made to solve the conventional problems as described above, and an X-ray generator is arranged at an appropriate position vertically above the center of the X-ray detector. An object of the present invention is to provide an X-ray foreign object detection device capable of preventing a decrease in resolution of an X-ray image due to the positional deviation of the X-ray.

  An X-ray foreign matter detection apparatus according to the present invention includes an X-ray source that irradiates an inspection object conveyed on a conveyance surface of a conveyance path with an X-ray and a plane orthogonal to the conveyance direction on a plane in the conveyance direction of the inspection object. A plurality of detection element arrays each including a plurality of detection elements arranged linearly in the main scanning direction in the transport direction, and the detection data obtained from each detection element for each stage of the plurality of detection element arrays is timed. An X-ray detector that synthesizes by delay integration and outputs combined data; and a determination unit that determines the presence or absence of foreign matter in the inspection object based on the combined data output by the X-ray detector. In the X-ray foreign object detection device, the X-ray detector outputs a detection data for each detection element array as a two-dimensional X-ray image in addition to a TDI read mode in which the combined data is output by the time delay integration. Has read mode A flat plate-shaped shielding member that is detachably provided on the X-ray detector and shields X-rays from the X-ray source passes through the front and back of the shielding member and extends in the extending direction of the shielding member. A jig formed of a plurality of vertical holes formed vertically to form a passage portion through which X-rays from the X-ray source pass, and the jig is disposed above the X-ray detector. In such a state, the X-ray source is positioned vertically above the center of the detection element array based on the two-dimensional X-ray image output by the X-ray detector in the frame readout mode. An adjustment determination means for determining the adjustment direction and adjustment amount of the source position, a display means for displaying the adjustment direction and adjustment amount determined by the adjustment determination means, and the X-ray source in a plane parallel to the transport surface Supporting means for supporting the position adjustment on the top. Characterized in that was.

  With this configuration, the display means displays the adjustment direction and adjustment amount of the X-ray source, and the user adjusts the position of the X-ray source according to the displayed adjustment direction and adjustment amount, thereby The position can be adjusted to an appropriate position vertically above the center of the X-ray detector. Therefore, the X-ray source can be disposed at an appropriate position vertically above the central portion of the X-ray detector, so that a reduction in the resolution of the X-ray image due to the positional deviation of the X-ray source can be prevented.

  Further, in the X-ray foreign object detection device according to the present invention, the adjustment determination means may be configured so that the portion where the X-ray intensity is highest in the two-dimensional X-ray image is in any direction with respect to the center of the two-dimensional X-ray image. The adjustment direction and the adjustment amount of the X-ray source are determined on the basis of the distance between them.

  With this configuration, since both the adjustment direction and the adjustment amount of the X-ray source can be determined at a time based on only the two-dimensional X-ray image, the adjustment determination unit can quickly determine.

  Moreover, the X-ray foreign material detection apparatus according to the present invention is characterized in that the passage portion includes a plurality of vertical holes opened in a lattice shape on the front and back of the shielding member.

  In the X-ray foreign object detection device according to the present invention, the passage portion includes a plurality of vertical holes opened in a slit shape extending in the main scanning direction on the front and back of the shielding member.

  The X-ray foreign object detection device according to the present invention includes a drive unit that displaces the X-ray source supported by the support unit on a plane parallel to the transport surface, and an adjustment direction determined by the adjustment determination unit. Drive control means for controlling the drive means in accordance with the adjustment amount.

  With this configuration, the drive control unit drives and controls the drive unit according to the determined adjustment direction and adjustment amount, so that the X-ray source can be automatically adjusted to an appropriate position.

  According to the present invention, the X-ray generator can be disposed at an appropriate position vertically above the central portion of the X-ray detector, so that the resolution of the X-ray image can be prevented from being lowered due to the displacement of the X-ray generator.

It is a perspective view which shows schematic structure of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. It is a figure which shows the side surface and internal structure of the X-ray foreign material detection apparatus which concern on one embodiment of this invention. It is a figure which shows the structure of the X-ray sensor of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. It is a figure which shows the position adjustment mechanism of the X-ray tube of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. It is a figure which shows the structure which mounted | wore the upper part of the X-ray sensor of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. It is a figure which shows the structure of the horizontal direction of an X-ray sensor, and is a figure which shows the state by which the X-ray tube is arrange | positioned in the appropriate position of the perpendicular upper direction of the conveyance direction center part of an X-ray sensor. It is a figure which shows the structure of the horizontal direction of an X-ray sensor, and is a figure which shows the state from which the X-ray tube has shifted | deviated from the appropriate position perpendicular | vertical upper direction of the conveyance direction center part of an X-ray sensor. (A) shows an X-ray image when the X-ray tube is arranged at an appropriate position vertically above the center of the X-ray sensor in the conveyance direction, and (b) shows the X-ray tube being conveyed by the X-ray sensor. It is a figure which shows an X-ray image when it has arrange | positioned and shifted | deviated from the appropriate position of the direction upper direction perpendicular | vertical upper part. It is a figure which shows the other structure of the jig | tool of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, the configuration will be described.

  As shown in FIG. 1, the X-ray foreign object detection device 1 includes a transport unit 2 and an inspection unit 3 inside a housing 4, and a display 5 on an upper front portion of the housing 4.

  The conveyance unit 2 sequentially conveys the inspection object W at a predetermined interval. This conveyance part 2 is comprised by the belt conveyor arrange | positioned horizontally within the housing | casing 4, for example. The transport unit 2 serves as a transport surface for the inspection object W loaded from the carry-in port 7 at a transport speed set in advance by driving the drive motor 6 shown in FIG. 1 toward the carry-out port 8 side (X direction in the figure). The belt surface 2a is conveyed.

  A space passing through the belt surface 2 a from the carry-in entrance 7 to the carry-out exit 8 within the housing 4 forms a transport path 21.

  The inspection unit 3 irradiates X-rays in the inspection space 22 in the middle of the conveyance path 21 with respect to the inspected objects W that are sequentially conveyed, and detects X-rays that pass through the inspection object W. An X-ray generator 9 disposed at a predetermined height above the inspection space 22 in the middle of 21 and an X-ray detector 10 disposed opposite to the X-ray generator 9 in the transport unit 2 are provided. ing.

  The X-ray generator 9 includes an X-ray tube 31 as a cylindrical X-ray source inside an X-ray unit 33 formed of a metal box. The unit 33 is insulated by insulating oil or insulating resin.

  In the present embodiment, the X-ray unit 33 that accommodates the X-ray tube 31 is moved on the X axis (conveying direction of the conveying unit 2) and on the Y axis (the width direction of the conveying unit 2) by a position adjusting mechanism described later. It is possible.

  The X-ray tube 31 generates X-rays by irradiating an anode target with an electron beam from the cathode. The X-ray tube 31 is arranged such that its longitudinal direction is the conveyance direction (X direction) of the inspection object W.

  The X-rays generated by the X-ray tube 31 are directed toward the lower X-ray detector 10 by a slit (not shown) disposed on the upper surface of the examination space 22 (see FIGS. 1 and 2). Thus, irradiation is performed so as to cross the transport direction (X direction). The slit is configured to be displaced together with the X-ray tube 31 that is displaced by the position adjusting mechanism.

  As shown in FIG. 3, the X-ray detector 10 has a plurality of detections in the Y direction orthogonal to the transport direction on the plane of the transport direction (X direction) of the object W to be transported as an X-ray detection unit. While arranging the elements in a straight line, an X-ray sensor 51 provided with a plurality of detection element rows in the transport direction of the inspection object W is provided. The X-ray sensor 51 is configured as a TDI (Time Delay Integration) sensor that outputs combined data obtained by time delay integration by repeatedly exposing and photographing the inspection object W by the number of stages of the detection element array for one line. Has been. The X-ray sensor 51 configured as a TDI sensor can obtain a high-resolution, bright and clear image as compared with a normal line sensor having one detection element array.

  In addition, the X-ray sensor 51 combines a detection data obtained from each detection element for each stage of a plurality of detection element arrays by time delay integration and outputs the combined data as a one-line X-ray image, and a time The readout mode can be switched between a frame readout mode in which detection data for each detection element array is output as a two-dimensional X-ray image of a frame having a size corresponding to the number of elements and the number of stages of the detection element array without performing delay integration. It is configured.

  As the TDI type sensor, for example, a sensor having 128 detection element rows in the direction of conveyance of the inspection object W can be used. However, in FIG. A configuration in which eight rows are provided in the conveyance direction of the inspection object W is illustrated.

  In FIG. 3, the X-ray sensor 51 arranges a plurality of detection elements in a straight line in the Y direction perpendicular to the transport direction on the plane in the width direction, that is, the transport direction (X direction) of the object W to be transported. In addition, a plurality of detection element arrays composed of a plurality of detection elements arranged in the Y direction are arranged in a plurality of stages in the transport direction (X direction), and configured as a TDI sensor.

  In the X-ray sensor 51, X-rays that have passed through the inspection object W are incident, and the detection elements of the X-ray sensor 51 output detection data based on the intensity of the X-rays incident on each detection element. In addition, X-ray image data corresponding to the readout mode is output.

  Specifically, as an example, the X-ray detection element includes a scintillator (not shown) that receives X-rays and emits light (fluorescence) at the top, converts the X-rays into light by the scintillator, and receives the light. Light is received by the element, converted into an electric signal, and detection data is output.

  As another example, X-rays may be directly and efficiently converted into an electrical signal using a semiconductor such as cadmium telluride (CdTe).

  Here, the X-ray image data output from the X-ray sensor 51 may be analog luminance value data (data indicating the detection amount), but in the present embodiment, the X-ray image data is provided at the subsequent stage of the X-ray sensor 51. Alternatively, data converted into digital data by an A / D converter (not shown) built in the X-ray sensor 51 is used. Note that the X-ray image data is obtained by converting the luminance value data into data indicating the X-ray absorption amount absorbed by the inspection object W, such as logarithmic conversion, so that the concentration increases as the absorption amount increases. The data image may be X-ray image data.

  The X-ray image data output from the X-ray sensor 51 is input to a general control unit 40 (see FIG. 2), which will be described later, and is used to determine whether foreign matter is mixed in the inspection object W in the TDI read mode. In the frame readout mode, it is used to determine the adjustment direction and adjustment amount of the X-ray tube 31.

  As shown in FIG. 2, X-ray shielding shielding curtains 16 are suspended and arranged at a plurality of locations along the conveyance direction (X direction) on the ceiling portion 21 a in the conveyance path 21. The shielding curtain 16 is composed of a rubber sheet mixed with lead powder that shields X-rays and processed into a good shape (a state in which the upper part is connected and the lower part is divided into strips), and is conveyed from the inspection space 22. This prevents X-rays from leaking outside the housing 4 via the path 21.

  In the present embodiment, two shielding curtains 16 are provided between the carry-in entrance 7 and the inspection space 22 and between the examination space 22 and the carry-out exit 8, respectively. Even when a gap is generated due to elastic deformation due to contact with the inspection object W, the other shielding curtain 16 shields X-rays, so that leakage of X-rays can be prevented without exceeding the leakage reference amount.

  Note that a slit is disposed on the upper surface of the inspection space 22, and the lower surface and side surfaces of the inspection space 22 are substantially closed by a housing 4 or the like for shielding X-rays. An inner space surrounded by the shielding curtain 16, the slit, the housing 4, and the like in the transport path 21 constitutes an inspection space 22.

  The X-ray foreign object detection apparatus 1 includes a comprehensive control unit 40 that performs comprehensive control including determination of the presence or absence of foreign objects in the inspection object W based on X-ray image data received from the X-ray sensor 51.

  The comprehensive control unit 40 performs comprehensive control of the X-ray foreign object detection device 1, and includes a data detection unit 61 that detects X-ray image data from the X-ray sensor 51 and validates the data, and data And a storage unit 43 for storing X-ray image data from the detection unit 61.

  The comprehensive control unit 40 also performs an image processing unit 44 that performs image processing such as synthesis processing and filtering processing on an image of X-ray image data (hereinafter also simply referred to as an X-ray image) from the X-ray sensor 51; The image processing unit 44 includes a determination unit 48 that determines whether the object W is in contact with the foreign object by determining whether the image is processed by the image processing unit 44. The determination result by the determination unit 48 is displayed on the display 5.

  The data detection unit 61 validates only the data input at a predetermined timing with respect to the X-ray image data from the X-ray sensor 51, that is, only the X-ray image data in the range of the predetermined data validation input timing. It is like that. When the X-ray sensor 51 outputs one line of X-ray image data in the TDI read mode, the data detection unit 61 obtains data corresponding to the number of lines corresponding to the length in the transport direction of the inspection object W. When the X-ray image data is validated and the X-ray sensor 51 outputs a two-dimensional X-ray image in the frame readout mode, a two-dimensional X-ray image of a frame having a size corresponding to the number of elements and the number of stages of the detection element array is acquired. The X-ray image data is validated until possible.

  The storage unit 43 temporarily stores X-ray image data output from the X-ray sensor 51 and validated by the data detection unit 61, and includes a memory capable of storing and reading images at high speed. ing.

  The image processing unit 44 performs image processing such as synthesis processing and filter processing on the X-ray image of the X-ray image data from the X-ray sensor 51.

  The determination unit 48 detects foreign matter from the inspected object W on the image subjected to the image processing by the image processing unit 44, and determines whether foreign matter is mixed. Note that the determination unit 48 determines the presence or absence of foreign matter in the X-ray image data output from the X-ray sensor 51 in the TDI readout mode.

  Further, the X-ray foreign object detection apparatus 1 is configured to select and select the X-ray output of the X-ray tube 31, the conveyance speed of the inspection object W, the inspection parameters of the inspection unit 3, the operation mode, the readout mode of the X-ray sensor 51, and the like. A setting unit for performing an operation is provided, and this setting unit is disposed next to the display 5 at the upper front of the housing 4. The setting unit and the display 5 may be an integrated type such as a touch panel.

  As shown in FIGS. 2 and 4, in this embodiment, as a mechanism for adjusting the positions of the X-ray tube 31 on the X axis and the Y axis, an X-ray unit including the X-ray tube 31 therein. A support mechanism 100 is provided to support 33 so as to be displaceable on the X and Y axes. Here, the X-ray unit 33 may have a mono tank configuration including a high voltage generation unit, or a configuration in which the high voltage generation unit is a separate unit.

  The support mechanism 100 includes a first stage 101 that supports an X-ray unit 33 provided with an X-ray tube 31 therein on the upper surface, a second stage 102 that supports the first stage 101 from below, and a second stage 102 that moves downward. And a third stage 103 supported from the outside.

  The first stage 101 is supported by the second stage 102 so as to be slidable on the Y axis when the convex portions 101a on the lower surfaces of both ends of the first stage 101 are guided in the concave portions 102a on the upper surface of the second stage 102. ing.

  The second stage 102 is supported by the third stage 103 so as to be slidable on the X axis when the convex portions 102c on the lower surfaces of both ends of the second stage 102 are guided in the concave portions 103c on the upper surface of the third stage 103. ing.

  On one end side of the second stage 102 on the Y-axis, a Y-axis adjusting member 111 that contacts the one end side of the first stage 101 and adjusts the position of the first stage 101 on the Y-axis is connected to the second stage 102. It is provided via a mounting stay 102b formed integrally or separately.

  On the other end side of the second stage 102 on the Y axis, a compression spring 113 is provided that contacts the other end side of the first stage 101 and presses the first stage 101 against the Y axis adjusting member 111 side. Yes.

  The Y-axis adjustment member 111 has a mechanism similar to that of a micrometer. When the Y-axis adjustment handle 111a is manually operated or rotated by the Y-axis drive motor 112, the plunger 111b moves forward or backward, and the first stage 101 The position on the Y axis is displaced.

  The Y-axis drive motor 112 is composed of a pulsed stepping motor, and its output shaft is connected to the Y-axis adjustment handle 111a.

  One end of the third stage 103 on the Y-axis is in contact with one end of an L-shaped member 116 rotatably provided on the second stage 102 to displace the other end of the L-shaped member 116. Thus, the X-axis adjusting member 114 that adjusts the position of the second stage 102 on the X-axis is provided via the mounting stay 103 b that is formed integrally with or separately from the third stage 103.

  On the other end side of the third stage 103, there is provided a compression spring 117 that contacts the other end side of the second stage 102 and presses the second stage 102 toward the X-axis adjusting member 114. The X-axis adjustment member 114 has the same mechanism as the micrometer. When the X-axis adjustment handle 114a is manually operated or rotated by the X-axis drive motor 115, the second stage is interposed via the L-shaped member 116. The position of 102 on the X axis is displaced.

  The X-axis drive motor 115 is composed of a pulsed stepping motor, and its output shaft is connected to the X-axis adjustment handle 114a.

  As shown in FIG. 5, in the present embodiment, a flat jig 55 having a plurality of vertical holes 55 a is provided on the top of the X-ray sensor 51 so as to be detachable from the X-ray sensor 51. Yes.

  The jig 55 is a flat shield member made of lead, tungsten, or the like that shields X-rays. The jig 55 penetrates the front and back of the shield member and is perpendicular to the extending direction of the flat plate. The vertical hole 55a is formed.

  In FIG. 5, the jig 55 includes a plurality of vertical holes 55 a having openings formed in a substantially square shape in a lattice shape. Further, the jig 55 has such a thickness that a part of the X-ray incident obliquely into the vertical hole 55a is shielded by the inner wall of the vertical hole 55a.

  Further, the jig 55 is formed in a size larger than that of the X-ray sensor 51 so that the vertical hole 55 a is disposed above all the detection elements of the X-ray sensor 51.

  In the jig 55 configured as described above, the vertical hole 55a functions as a passing part that allows passage of X-rays, and the part other than the vertical hole 55a functions as a shielding part that blocks X-rays.

  As shown in FIGS. 6 and 7, the jig 55 provided on the upper part of the X-ray sensor 51 is arranged so that the X-rays are perpendicular to the vertical hole 55a at the part vertically below the X-ray tube 31 arranged on the upper part. More X-rays are allowed to enter, and at a portion away from the vertically lower side of the X-ray tube 31, X-rays enter the vertical hole 55a obliquely so that less X-rays are allowed to pass.

  In addition, as shown in FIG. 6, when the X-ray tube 31 is disposed at an appropriate position vertically above the central portion in the transport direction of the X-ray sensor 51, the X-ray sensor that has passed through the vertical hole 55 a of the jig 55. As shown in FIG. 8A, the X-ray image data in the frame readout mode from 51 has the highest X-ray intensity in the portion corresponding to the central portion in the transport direction of the X-ray sensor 51. As the distance from the central portion in the transport direction increases, the X-ray image becomes concentrically weakened.

  On the other hand, as shown in FIG. 7, when the X-ray tube 31 is arranged so as to be shifted from the vertically upper side of the central portion in the transport direction of the X-ray sensor 51 to the downstream side in the transport direction, it passes through the vertical hole 55 a of the jig 55. The X-ray image data in the frame readout mode from the X-ray sensor 51 corresponds to a position shifted from the vertically upper side in the transport direction center of the X-ray sensor 51 to the downstream side in the transport direction, as shown in FIG. The X-ray image has the strongest X-ray intensity in the portion where it is, and the intensity decreases concentrically as the distance from this portion increases.

  In FIG. 8A and FIG. 8B, for ease of explanation, the X-ray intensity is drawn so as to gradually decrease as the distance from the center portion increases. The intensity of X-rays continuously decreases as the distance from the central portion increases.

  As described above, by providing the jig 55 having the vertical hole 55 a on the upper portion of the X-ray sensor 51, the positional relationship between the position of the central portion of the X-ray sensor 51 and the position of the X-ray tube 31 can be grasped. It is possible to know which part of the X-ray sensor 51 the X-ray tube 31 is disposed vertically above.

  As shown in FIG. 9, the jig 55 passes through the front and back surfaces of the shielding member made of lead, tungsten or the like that shields X-rays and extends in the direction of extension of the flat plate. You may comprise from what formed the several vertical hole 55a formed perpendicularly | vertically and opening in the slit shape extended in the main scanning direction.

  That is, the shape of the opening of the vertical hole 55a is not limited to a substantially square arrayed in a lattice shape, but may be a slit shape extending in the main scanning direction and arranged in the transport direction. Further, the shape of the vertical hole 55a may be a shape other than a substantially square or slit shape.

  Even when the shape of the vertical hole 55a serving as the X-ray passage portion is a slit shape, the X-ray image data in the frame readout mode from the X-ray sensor 51 that has passed through the vertical hole 55a is shown in FIG. 8 (b) is substantially the same, and the X-ray intensity is the strongest at the portion corresponding to the central portion in the transport direction of the X-ray sensor 51, and the strength decreases as the distance from the central portion in the transport direction of the X-ray sensor 51 increases. It becomes an image. When the shape of the vertical hole 55a is a slit shape, the shape of the X-ray image data is not a concentric circle but an ellipse extending in the main scanning direction.

  Based on the X-ray image data output by the X-ray sensor 51 in the frame readout mode with the jig 55 mounted, the general control unit 40 is configured so that the X-ray tube 31 is vertically above the center of the X-ray sensor 51. An adjustment determination unit 81 is provided as means for determining an adjustment direction and an adjustment amount of the position of the X-ray tube 31 to be a position.

  In the following description, a case where the adjustment determination unit 81 determines the adjustment direction and adjustment amount on the X-axis of the X-ray tube 31 will be described. However, the adjustment determination unit 81 adjusts the Y-axis of the X-ray tube 31 on the Y-axis. The direction and adjustment amount are also determined in the same manner as described below.

  Regarding the two-dimensional X-ray image output from the X-ray sensor 51 in the frame readout mode, the adjustment determination unit 81 has a portion with the highest X-ray intensity in the X-ray image with respect to the center of the X-ray image. The adjustment direction and adjustment amount of the X-ray tube 31 are determined on the basis of which distance in which direction.

  For example, as illustrated in FIG. 8B, the adjustment determination unit 81 has a portion Cx having the highest X-ray intensity in the two-dimensional X-ray image, downstream in the transport direction with respect to the center Cs of the X-ray image. When the distance is away by the distance D, it is determined that the adjustment direction of the X-ray tube 31 is the upstream side in the transport direction and the adjustment amount is the distance D. The two-dimensional X-ray image output from the X-ray sensor 51 in the frame readout mode is an image having a size corresponding to the number of elements and the number of stages of the detection element array of the X-ray sensor 51. The center Cs coincides with the center of the X-ray sensor 51.

  Further, the adjustment determination unit 81 outputs the determination result to the display unit 5. For example, a message such as “adjustment X direction axis minus direction (upstream in the transport direction), adjustment amount: 1.5 mm” is displayed on the display 5 as the adjustment direction and adjustment amount of the X-ray tube 31.

  The overall control unit 40 includes a drive control unit 82 that controls the drive of the Y-axis drive motor 112 and the X-axis drive motor 115 according to the adjustment direction and adjustment amount of the X-ray tube 31 determined by the adjustment determination unit 81. .

  The drive control unit 82 determines drive pulses for the Y-axis drive motor 112 and the X-axis drive motor 115 according to the adjustment direction and adjustment amount determined by the adjustment determination unit 81, and the Y-axis drive motor 112, The X-axis drive motor 115 is driven.

  For this reason, when the adjustment direction and the adjustment amount of the X-ray tube 31 are determined, the adjustment direction and the adjustment amount are displayed on the display 5, and the Y-axis drive motor 112 and the X-axis drive motor 115 are driven by the drive control unit 82. Is controlled to adjust the position of the X-ray tube 31 on the two axes to an appropriate position.

  In the present embodiment, there are an automatic adjustment mode and a manual adjustment mode as operation modes of the overall control unit 40. When the operation mode is set to the automatic adjustment mode, both the display of the adjustment direction and the adjustment amount by the display 5 and the drive control of the Y-axis drive motor 112 and the X-axis drive motor 115 by the drive control unit 82 are performed. .

  On the other hand, when the operation mode is set to the manual adjustment mode, only the adjustment direction and the adjustment amount are displayed on the display 5, and the user operates the Y-axis adjustment handle 111a and the X-axis adjustment handle 114a. ing.

  Next, the operation of the X-ray foreign object detection apparatus 1 configured as described above will be described.

  First, when the operation mode is set to the automatic adjustment mode, the comprehensive control unit 40 acquires X-ray image data output from the X-ray sensor 51 with the jig 55 mounted, and an adjustment determination unit. 81, the X-ray tube 31 has the highest X-ray intensity in the X-ray image data on the X-ray tube 31 on the basis of which distance and distance from the center of the X-ray image. The adjustment direction and the adjustment amount are determined, the determination result is displayed on the display 5, and the X-axis drive motor 115 is driven and controlled by the drive control unit 82.

  As a result, the position of the X-ray tube 31 on the X-axis is adjusted to an appropriate position vertically above the center of the X-ray sensor 51.

  On the other hand, when the operation mode is set to the manual adjustment mode, the comprehensive control unit 40 acquires the X-ray image data output from the X-ray sensor 51 with the jig 55 mounted, and the adjustment determination unit 81, the X-ray tube 31 has the highest X-ray intensity in the X-ray image data on the X-ray tube 31 on the basis of which distance and distance from the center of the X-ray image. The adjustment direction and the adjustment amount are determined, and the determination result is displayed on the display 5.

  As a result, when the user operates the X-axis adjustment handle 114 a, the position on the X-axis of the X-ray tube 31 is adjusted to an appropriate position vertically above the center of the X-ray sensor 51.

  As described above, the X-ray foreign object detection device 1 according to the present embodiment includes the X-ray tube 31 that irradiates the inspection object W conveyed on the belt surface 2a with X-rays, and the conveyance direction of the inspection object W. A plurality of detection element arrays each including a plurality of detection element arrays, each including a plurality of detection elements arranged linearly in a main scanning direction (Y direction) orthogonal to the transport direction on a plane in the (X direction). X-ray sensor 51 for outputting X-ray image data obtained by synthesizing detection data obtained from each detection element for each stage by time delay integration, and inspected object W based on synthesized data output by X-ray sensor 51 In addition to the TDI readout mode in which the X-ray sensor 51 outputs combined data by time delay integration, the detection data for each detection element array is converted into a two-dimensional X-ray image. Frame readout mode to output as A flat plate-shaped shielding member that is detachably provided on the X-ray sensor 51 and shields X-rays from the X-ray tube 31 and extends through the front and back of the shielding member. A jig 55 formed of a plurality of vertical holes 55 a formed perpendicular to the X-ray tube 31 and passing a X-ray from the X-ray tube 31, and the jig 55 is disposed above the X-ray sensor 51. In the installed state, the X-ray tube 31 is positioned vertically above the center of the detection element array based on the two-dimensional X-ray image output by the X-ray sensor 51 in the frame readout mode. An adjustment determination unit 81 that determines the adjustment direction and adjustment amount of the position, a display 5 that displays the adjustment direction and adjustment amount determined by the adjustment determination unit 81, and the X-ray tube 31 are parallel to the belt surface 2a. Support mechanism 1 that supports a position adjustable on a plane 0, characterized by comprising a.

  With this configuration, the display unit 5 displays the adjustment direction and adjustment amount of the X-ray tube 31, so that the user adjusts the position of the X-ray tube 31 in accordance with the displayed adjustment direction and adjustment amount. The position of the ray tube 31 can be adjusted to an appropriate position vertically above the center of the X-ray sensor 51. Therefore, the X-ray tube 31 can be arranged at an appropriate position vertically above the center of the X-ray sensor 51 to prevent the resolution of the X-ray image from being lowered due to the positional deviation of the X-ray tube 31.

  In addition, in the X-ray foreign object detection device 1 according to the present embodiment, the adjustment determination unit 81 determines which part of the two-dimensional X-ray image has the highest X-ray intensity relative to the center of the two-dimensional X-ray image. The adjustment direction and the adjustment amount of the X-ray tube 31 are determined based on which distance is away in the direction.

  With this configuration, since both the adjustment direction and the adjustment amount of the X-ray tube 31 can be determined at a time based on only the two-dimensional X-ray image, the adjustment determination unit 81 can be determined quickly.

  In addition, the X-ray foreign object detection device 1 according to the present embodiment is characterized in that the passage portion includes a plurality of vertical holes 55a that open in a lattice shape on the front and back of the shielding member.

  In addition, the X-ray foreign object detection device 1 according to the present embodiment is characterized in that the passage portion includes a plurality of vertical holes 55a that open in slit shapes extending in the main scanning direction on the front and back of the shielding member.

  In addition, the X-ray foreign object detection device 1 according to the present embodiment has a Y-axis drive motor 112 and an X-axis drive motor 115 that displace the X-ray tube 31 supported by the support mechanism 100 on a plane parallel to the belt surface 2a. And a drive control unit 82 for controlling the Y-axis drive motor 112 and the X-axis drive motor 115 in accordance with the adjustment direction and the adjustment amount determined by the adjustment determination unit 81.

  With this configuration, the drive control unit 82 drives and controls the X-axis drive motor 115 and the Y-axis drive motor 112 according to the determined adjustment direction and adjustment amount, so that the X-ray tube 31 is automatically adjusted to an appropriate position. be able to.

  As described above, in the X-ray foreign object detection device according to the present invention, the X-ray generation unit is disposed at an appropriate position vertically above the center of the X-ray detector, and the X-ray image is generated by the positional deviation of the X-ray generation unit. Therefore, it is useful as an X-ray foreign matter detection apparatus employing a TDI sensor as an X-ray detector.

DESCRIPTION OF SYMBOLS 1 X-ray foreign material detection apparatus 2 Conveyance part (conveyance means)
2a Belt surface (conveying surface)
3 Detection unit 4 Housing 5 Display (display means)
9 X-ray generator 10 X-ray detector 21 Transport path 31 X-ray tube (X-ray source)
40 general control unit 43 storage unit 44 image processing unit 48 determination unit (determination means)
49 Setting part 51 X-ray sensor 55 Jig 55a Vertical hole 81 Adjustment determination part (Adjustment determination means)
82 Drive control unit (drive control means)
100 Support mechanism (support means)
111 Y-axis adjusting member (supporting means)
112 Y-axis drive motor (drive means)
114 X-axis adjustment member (support means)
115 X-axis drive motor (drive means)

Claims (5)

An X-ray source (31) for irradiating the inspection object conveyed on the conveyance surface of the conveyance path with X-rays;
A plurality of detection element arrays each including a plurality of detection elements arranged in a straight line in the main scanning direction (Y direction) orthogonal to the conveyance direction on a plane in the conveyance direction (X direction) of the inspection object. An X-ray detector (51) for synthesizing detection data obtained from each detection element for each stage of the plurality of detection element arrays by time delay integration and outputting synthesized data;
A determination means (48) for determining the presence or absence of foreign matter in the inspection object based on the composite data output by the X-ray detector;
The X-ray detector has a frame readout mode for outputting detection data for each detection element array as a two-dimensional X-ray image in addition to the TDI readout mode for outputting the combined data by the time delay integration.
A flat plate-shaped shielding member that is detachably provided on the X-ray detector and shields X-rays from the X-ray source passes through the front and back of the shielding member and extends in the extending direction of the shielding member. And a jig (55) formed of a plurality of vertical holes (55a) formed vertically to form a passing portion through which X-rays from the X-ray source pass.
Based on the two-dimensional X-ray image output by the X-ray detector in the frame reading mode in a state where the jig is disposed on the X-ray detector, the X-ray source is the detection element. An adjustment determination means (81) for determining an adjustment direction and an adjustment amount of the position of the X-ray source so as to be a position vertically above the center of the row;
Display means (5) for displaying the adjustment direction and the adjustment amount determined by the adjustment determination means;
An X-ray foreign matter detection apparatus comprising: support means (100) for supporting the X-ray source so that the position of the X-ray source can be adjusted on a plane parallel to the transport surface.   The adjustment determining means determines whether the portion where the X-ray intensity is highest in the two-dimensional X-ray image is separated in which direction and in which direction with respect to the center of the two-dimensional X-ray image. The X-ray foreign matter detection means according to claim 1, wherein an adjustment direction and an adjustment amount of the radiation source are determined.   The X-ray foreign matter detection means according to claim 1, wherein the passage portion includes a plurality of vertical holes opened in a lattice shape on the front and back of the shielding member.   3. The X-ray foreign matter detection unit according to claim 1, wherein the passage portion includes a plurality of vertical holes opened in a slit shape extending in the main scanning direction on the front and back of the shielding member. . Drive means (112, 115) for displacing the X-ray source supported by the support means on a plane parallel to the transport surface;
The driving control means (82) which controls the said drive means according to the adjustment direction and adjustment amount which were determined by the said adjustment determination means, The drive control means (82) characterized by the above-mentioned. X-ray foreign object detection device.

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