JP2012154741A - X-ray foreign matter detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray foreign matter detector capable of preventing interference of X-rays with different radiation qualities from occurring in a detection step.SOLUTION: An X-ray foreign matter detector comprises: a conveying part 2 for conveying an inspection object W through a conveyance path; an X-ray generator 9 for irradiating the inspection object conveyed through the conveyance path with a plurality of X-rays; an X-ray detector 10 for outputting detection data in accordance with the X-rays emitted by the X-ray generator 9 and transmitting the inspection object W; a rotary plate 70 that is disposed between the X-ray generator 9 and the X-ray detector 10 to be rapidly rotated around a rotational axis, includes a shielding portion 71 for shielding X-rays and a transmitting portion 72 for transmitting X-rays alternately provided in a rotation direction, so as to separate the plurality of X-rays from the X-ray generator 9 over time by rapidly rotating around the rotational axis for successively transmitting any one of the plurality of X-rays; and a determining part 48 for determining whether or not there is foreign matter included in the inspection object W on the basis of the detection data output by the X-ray detector 10.

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 food, and pharmaceuticals, and in particular, simultaneously irradiates a plurality of X-rays on one object to be inspected during transportation. The present invention relates to an X-ray foreign object detection device.

  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 line sensor that detects first X-ray tube and second X-ray tube as X-ray sources, and transmitted X-rays from the first X-ray tube and second X-ray tube, respectively. A first line sensor and a second line sensor, and irradiating X-rays simultaneously from the first X-ray tube and the second X-ray tube, and the first X-ray tube and the second X-ray by the first line sensor and the second line sensor. One that detects transmitted X-rays from a ray tube is known (see, for example, Patent Document 1).

JP-A-10-104175

  However, in the conventional technique described in Patent Document 1, in the case where a pair of an X-ray source and an X-ray line sensor are arranged close to each other, for example, transmitted X-rays from a first X-ray tube are generated. As a result, the pair of one X-ray source and the X-ray line sensor may be affected by the X-ray of the other pair of X-ray source and X-ray line sensor. In contrast, the time for performing X-ray irradiation and detection by the pair of the first X-ray tube and the first line sensor and the time for performing X-ray irradiation and detection by the pair of the second X-ray tube and the second line sensor are divided. It seems that the above problem can be solved, but it is impossible to alternately turn on and off the first X-ray tube and the second X-ray tube at high speed in order to cope with the inspected object that is being transported and constantly moving. Therefore, another method has been demanded.

  Accordingly, the present invention has been made to solve the conventional problems as described above, and provides an X-ray foreign object detection device capable of preventing X-rays having different radiation qualities from interfering at the detection stage. The purpose is that.

  An X-ray foreign matter detection apparatus according to the present invention includes X-ray generation means for generating X-rays and X-ray detection means for receiving X-rays from the X-ray generation means, and the X-ray generation means and the X-ray generation means X-ray foreign object detection for irradiating an inspection object conveyed in a predetermined conveying direction in the inspection space between the line detection means with X-rays and determining the presence or absence of the foreign object in the inspection object based on the amount of transmission The apparatus is arranged at the upper part of the examination space, is provided at a position to receive the X-rays output from the X-ray generation means, and sequentially switches and outputs the line quality by a rotating plate that rotates about an axis. Radiation quality switching means, and determination means for determining the presence or absence of foreign matter in the inspection object based on the detection data corresponding to the X-rays from the radiation quality switching means detected by the X-ray detection means. It is characterized by that.

  With this configuration, X-rays output from the X-ray generation means are sequentially switched and output by the rotating plate rotated by the quality switching means, so that the X-ray detection means is time-separated for each quality. Can receive X-rays. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  In the X-ray foreign matter detection apparatus according to the present invention, the X-ray detection means outputs detection data for each X-ray quality to be detected, and the detection for each X-ray quality output from the X-ray detection means. Image synthesizing means for synthesizing data and outputting it as one image data corresponding to the object to be inspected, and the determination means in the inspected object based on the image data output from the image synthesizing means It is characterized by determining the presence or absence of foreign matter.

  With this configuration, X-rays having different radiation qualities can be used, and the detection data from the X-ray detection means can be combined to reduce the influence of the thickness of the object to be inspected and obtain an image in which foreign matter is emphasized. it can.

  Further, in the X-ray foreign object detection device according to the present invention, the X-ray generation means includes first and second X-ray sources that output X-rays having different radiation qualities, and the radiation quality switching means includes the The rotating plate is provided with shielding portions that shield X-rays and transmitting portions that transmit X-rays alternately around the axis, and rotates from the first and second X-ray sources by rotating about the axis. One of the output X-rays sequentially transmits one X-ray and the other X-rays are sequentially shielded to sequentially switch the line quality.

  With this configuration, the rotating plate that rotates the quality switching means sequentially transmits one X-ray output from each of the first and second X-ray sources and sequentially blocks the other X-rays. The X-ray detection means can receive X-rays that are separated for each quality. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  Further, in the X-ray foreign object detection device according to the present invention, the radiation quality switching means is configured to transmit the X-rays with the first transmission part that transmits the X-rays with the first radiation quality to the rotating plate, and with the second radiation quality. The second transmissive portions to be transmitted are alternately provided around the axis, and the line quality is sequentially switched by rotating around the axis.

  With this configuration, the X-ray detection means can receive X-rays that are time-separated into the first and second radiation qualities from the rotating rotating plate. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  Moreover, the X-ray foreign matter detection apparatus according to the present invention is characterized in that one of the X-ray quality detected by the X-ray detection means is high energy X-ray and the other is low energy X-ray. To do.

  With this configuration, by using high-energy X-rays and low-energy X-rays, it is possible to obtain an image in which the influence of the thickness of the inspection object is reduced and the foreign matter is emphasized.

  In the X-ray foreign object detection device according to the present invention, the rotating plate may be arranged in a rotational direction of a portion that outputs the low energy X-rays rather than a width in a rotational direction of the portion that outputs the high energy X-rays. It is characterized by its wide width.

  With this configuration, the time that the X-ray detection unit receives low-energy X-rays is longer than the time that the X-ray detection unit receives high-energy X-rays, and an X-ray image with high contrast can be obtained.

  The X-ray foreign object detection device according to the present invention further includes a rotating plate moving unit that changes a position of the rotating plate with respect to the X-ray generating unit, and the rotating plate is moved from the inner peripheral portion near the rotating shaft. The width of the transmission part in the rotation direction becomes wider toward the outer peripheral part far from the rotation axis.

  With this configuration, by changing the position of the rotating plate by the rotating plate moving means, it is possible to change the duty ratio of X-rays having different quality that are output from the quality switching means.

  Further, the X-ray foreign object detection apparatus according to the present invention enables the output timing changing means for changing the timing at which the X-ray detection means outputs detection data, and the detection data output from the X-ray detection means to be effective at a predetermined timing. And a detection data validation means for converting the data.

  With this configuration, it is possible to reliably separate X-rays having different radiation qualities by changing the timing at which the detection data is output and enabling the detection data at a predetermined timing.

  The present invention can provide an X-ray foreign object detection device capable of preventing X-rays having different radiation qualities from interfering at the detection stage.

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. (A)-(d) is a figure which shows the rotary plate for the time separation of the X-ray of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. It is a timing chart which shows the timing of X-ray light reception and reading of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. (A)-(c) is a figure which shows the example of a combination of the X-ray source and light receiving element of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. (A)-(c) is a figure which shows the example of arrangement | positioning of the rotating plate of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention. (A), (b) is a figure which shows the example of a combination of the light receiving element of the X-ray foreign material detection apparatus which concerns on one embodiment of this invention, and a data detection part.

  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 a detection unit 3 inside a housing 4, and a display 5 at the upper front 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 that penetrates the belt surface 2 a from the carry-in port 7 to the carry-out port 8 in the housing 4 forms a transport path 21.

  The detection unit 3 irradiates the inspection object W sequentially conveyed with X-rays in the inspection space 22 in the middle of the conveyance path 21 and detects X-rays transmitted through the inspection object W. 21 includes an X-ray generator 9 disposed at a predetermined height above the examination space 22 in the middle of the 21 and an X-ray detector 10 disposed opposite to the X-ray generator 9 in the transport unit 2. Yes.

  An X-ray generator 9 as an X-ray generation source has a configuration in which a cylindrical X-ray tube 30 provided inside a metal box 11 is immersed in insulating oil (not shown). In the present embodiment, two X-ray tubes 31 and 32 are provided as the X-ray tube 30, and an X-ray is generated by irradiating an anode target with an electron beam from the cathodes of the X-ray tubes 31 and 32. . The X-ray tubes 31 and 32 are arranged such that the longitudinal direction thereof is the conveyance direction (X direction) of the inspection object W. X-rays generated by the X-ray tubes 31 and 32 are irradiated toward the lower X-ray detector 10 so as to cross the transport direction (X direction) in a substantially triangular screen shape by a slit (not shown). It has become so.

  Here, the intensity of the X-rays generated by the X-ray tubes 31 and 32 changes in proportion to the current (tube current) flowing between the anode and the cathode of the X-ray tubes 31 and 32 and the generated X-rays. Is shortened according to the voltage (tube voltage) applied between the anode and cathode of the X-ray tubes 31 and 32, and the transmission power is increased. That is, the quality of X-rays generated from the X-ray tubes 31 and 32 changes according to the tube current and tube voltage of the X-ray tubes 31 and 32. In the present embodiment, the intensity of X-rays generated by the X-ray tube 31 and the intensity of X-rays generated by the X-ray tube 31 are made different. For example, the X-ray tube 31 has a high output (high energy radiation quality). X-ray is output), and the X-ray tube 32 is set to low output (low energy X-ray output is output). Note that the intensity of X-rays generated by the X-ray tubes 31 and 32 is not necessarily fixed at a constant value, and the X-ray tube is in accordance with the type of foreign matter to be detected and the inspection object W and the conveyance speed. The tube currents or tube voltages 31 and 32 are adjusted.

  The X-ray detector 10 includes an X-ray line sensor 50 in which a plurality of detection elements are linearly arranged in the Y direction orthogonal to the transport direction on the plane in the transport direction (X direction) of the object W to be transported. ing. In the present embodiment, as the X-ray line sensor 50, two X-ray line sensors 51 and 52 are provided in the conveyance direction of the inspection object W, and the X-ray line sensor 51 is irradiated from the high-power X-ray tube 31. Then, a detection signal (density data image) transmitted through the inspection object W is output, and the X-ray line sensor 52 detects the detection signal (density data) irradiated from the high-output X-ray tube 32 and transmitted through the inspection object W. Image). The X-ray line sensors 51 and 52 include a scintillator (not shown) that emits light (fluorescence) upon receiving X-rays and a light receiving element that receives light from the scintillator.

  Here, in the present embodiment, the X-ray detector 10 converts the detection signals (luminance value data) of the X-ray line sensors 51 and 52 into digital data by a built-in A / D converter (not shown), and density data. The A / D converter is provided outside the X-ray detector 10, or the luminance value data before A / D conversion is output to the control unit 40 in the subsequent stage. A configuration may be adopted, and conversion into density data, which is digital data, is not an essential requirement.

  The X-ray detector 10 including the X-ray line sensors 51 and 52 outputs image data necessary for determining whether or not foreign matter is mixed in a control unit 40 (see FIG. 2) described later.

  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 control unit 40 that receives density data from the X-ray detector 10 and determines the presence or absence of foreign substances in the inspection object W.

  The control unit 40 includes data detection units 61 and 62 that perform a thinning process for validating only the density data input at a predetermined timing with respect to the density data from the X-ray line sensors 51 and 52, and the data detection unit 61. 62 for the density data of the X-ray line sensors 51 and 52 (hereinafter simply referred to as “images”). The image processing unit 44 that performs image processing such as synthesis processing and filter processing, and the image subjected to image processing by the image processing unit 44 is discriminated from the inspected object W and foreign matter to determine whether foreign matter is mixed in. And a determination unit 48 for determining whether or not. The determination result by the determination unit 48 is displayed on the display 5.

  The data detection unit 60 includes two data detection units 61 and 62 in the present embodiment, and validates only the density data input at a predetermined timing with respect to the density data from the X-ray line sensors 51 and 52, respectively. It is supposed to be. Specifically, as shown in FIG. 4, data detectors 61 and 62 (represented as data detectors D1 and D2 in FIG. 4) are light receiving elements (in FIG. 4, light receiving elements). Among the data from the elements R1 and R2), only the data within the range of the data validation input timing is adopted and validated, and output to the storage unit 43 at the subsequent stage.

  The storage unit 43 temporarily stores data validated by the data detection units 61 and 62 among the data output from the X-ray line sensors 51 and 52, and can store and read images at high speed. It consists of possible memory.

  The image processing unit 44 performs image processing such as synthesis processing and filter processing on the density data images from the X-ray line sensors 51 and 52.

  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.

  The X-ray foreign object detection apparatus 1 also includes a setting unit 49 that performs an X-ray output of the X-ray generator 9, a conveyance speed of the inspection object W, an inspection parameter setting operation of the X-ray detector 10, and a selection operation. The setting unit 49 is arranged next to the display 5 at the upper front of the housing 4.

  The X-rays output from the X-ray tubes 31 and 32 above or above the examination space 22 are rotated around the rotation axis so that the quality of the received X-rays is sequentially switched and output. A rotating plate 70 is provided. The rotating plate 70 may be located on either the upper surface side or the lower surface side of the slit. However, when the rotating plate 70 is provided on the lower surface side of the slit (upper part in the inspection space 22), as described above. The X-rays generated by the X-ray tubes 31 and 32 are irradiated toward the lower X-ray detector 10 in a substantially triangular screen shape by a slit (not shown) so as to cross the transport direction (X direction). For this reason, it is preferable that the width of the X-ray is provided immediately below the relatively narrow slit. Since the rotating plate 70 rotates at a high speed, the upper surface side of the slit (inside the X-ray generator 9) or the lower surface side of the slit together with the rotating plate cover (not shown) from the viewpoint of safety or stability. It is even better if it is provided (in the upper part of the inspection space 22).

  As shown in FIG. 3A, the rotary plate 70 is configured by alternately arranging shielding portions 71 made of a member that shields X-rays and transmitting portions 72 that transmit X-rays, and an X-ray tube. 31 and X-rays output from the X-ray tube 32 are arranged at a position where one of the X-rays is sequentially transmitted by the transmission part 72 and the other is sequentially shielded by the shielding part 71. One of the X-rays output from the tube 32 is sequentially transmitted and the other is sequentially shielded, so that the X-ray quality is sequentially switched and output. The rotating plate 70 has, for example, a diameter of about 30 cm, a circumferential width of the transmission part 72 is substantially constant from the outer peripheral part to the inner peripheral part, about 1.5 mm, and the rotational speed is 1200 rpm, and about 314 times per second. X-ray shielding and transmission are repeated. In the rotating plate 70, the width in the circumferential direction of the transmission portion 72 is substantially constant between the outer peripheral portion and the inner peripheral portion, whereas the circumferential width of the shielding portion 71 is wider at the outer peripheral portion and narrower at the inner peripheral portion. Yes. For this reason, the ratio of the width of the transmitting portion 72 and the shielding portion 71 in the circumferential direction of the rotating plate 70 is large at the outer peripheral portion and small at the inner peripheral portion. In the example of FIG. 3A, the shielding part 71 is formed of a member that shields X-rays in a propeller shape, and a notch-like space in the gap of the shielding part 71 is formed as the transmission part 72. However, for the purpose of maintaining the strength and the convenience in the manufacturing process, the transmission part 72 may be formed of a member made of a material that can be regarded as substantially transmitting X-rays.

  Further, as shown in FIG. 3B, the rotating plate 70 includes a shielding unit 71 and a transmitting unit 72, and a filter unit 73 that transmits X-rays at different ratios and makes X-ray quality different. In this case, by rotating, one of the X-rays output from the X-ray tube 31 and the X-ray tube 32 is sequentially transmitted or has a different quality, and the other is sequentially shielded, thereby The line quality can be sequentially switched and output. The filter part 73 can be comprised from the member from which a material differs from the member which comprises the shielding part 71, or can be comprised from the member from which the material is the same as the shielding part 71, and thickness differs.

  Note that the X-ray tube 30 includes only one X-ray tube (for example, the X-ray tube 31), and the rotating plate 70, as shown in FIG. The first filter part 75 to transmit and the second filter part 76 to transmit X-rays with the second radiation quality may be alternately provided around the axis. In this case, the rotating plate 70 has the axis. By rotating around the center, the quality of X-rays transmitted through the rotating plate 70 is sequentially switched to either the first quality or the second quality.

  Further, as shown in FIG. 3D, the rotating plate 70 may have a narrow shape in which the circumferential width of the shielding portion 71 is narrow at the outer peripheral portion and wide at the inner peripheral portion. In this case, the ratio of the width of the transmitting portion 72 and the shielding portion 71 in the circumferential direction of the rotating plate 70 is small at the outer peripheral portion and large at the inner peripheral portion. In the configuration of FIG. 3D, by providing the moving mechanism 74 that moves the position of the rotation axis of the rotating plate 70, the time for shielding the X-ray from the X-ray source X1 and the X-ray from the X-ray source X2 are reduced. The time for shielding can be adjusted. In FIG. 3D, the time for shielding the X-ray from the X-ray source X1 is short, and the time for shielding the X-ray from the X-ray source X2 is long.

  Next, the operation when the rotating plate 70 of FIG. 3A is used will be described with reference to the configuration diagram of FIG. 2 and the timing chart of FIG. In FIG. 4, X-ray sources X1 and X2 correspond to the X-ray tubes 31 and 32 in FIG. 2, and data detection units D1 and D2 correspond to the data detection units 61 and 62 in FIG.

  The control unit 40 drives the conveyance unit 2 at a preset speed to convey the inspection object W, and also inspects the inspection object from the X-ray line sensors 51 and 52 of the X-ray generator 9 with a predetermined intensity. W is irradiated with X-rays.

  The X-rays emitted from the X-ray sources X1 and X2 are arranged in a substantially triangular screen shape by slits (not shown), and then alternately pass through rotating rotating plates 70 as shown in FIG. Thereby, the X-rays from the X-ray sources X1 and X2 are time-separated.

  The X-rays that have passed through the rotary plate 70 are output as detection data (electrical signals) from the light receiving elements R1 and R2 at a predetermined reading timing. The reading timing of the light receiving elements R1 and R2 is set to be shorter than the respective time widths of the X-rays that have alternately passed through the rotating plate 70, and can be changed.

  For the detection data output from the light receiving elements R1 and R2, only the data portion within the time width of the data validation input timing is validated by the decimation process in the data detection units D1 and D2. In the data detection units D1 and D2, the data validation input timing can be automatically adjusted based on the change in the X-ray luminance.

  The detection data validated by the data detection units D1 and D2 is stored in the storage unit 43, and then subjected to image processing such as synthesis by the image processing unit 44. The presence or absence of foreign matter is determined by the determination. This determination result is displayed on the display 5.

  Here, a combination example of the X-ray source and the light receiving element of the X-ray foreign matter detection apparatus 1 will be described with reference to FIGS.

  As to the combination of the X-ray source and the light receiving element, as shown in FIG. 5A, a plurality of X-ray sources X1, X2,..., Xn and a plurality of light receiving elements R1, R2,. , Rn allows the light receiving elements R1, R2,..., Rn to set appropriate gains according to the X-ray outputs of the paired X-ray sources X1, X2,. it can.

  Further, as shown in FIG. 5B, the X-rays from the plurality of X-ray sources X1, X2,..., Xn are aggregated in one place, and the plurality of light receiving elements R1, R2 are gathered at the place where the X-rays are aggregated. ,..., Rn are sequentially arranged below, the X-ray from the X-ray source X1 is detected by the uppermost light receiving element R1, and the X-ray from the X-ray source X2 is detected by the second-stage light receiving element R2. The X-ray from the X-ray source Xn may be detected by the n-th light receiving element Rn.

  Further, as shown in FIG. 5 (c), the X-rays from the plurality of X-ray sources X1, X2,..., Xn are aggregated at one place, and one light receiving element R1 is disposed at the place where the X-rays are aggregated. However, all X-rays from the X-ray sources X1, X2,..., Xn may be detected by the light receiving element R1.

  5A to 5C, X-rays from the X-ray sources X1, X2,..., Xn are time-separated by the rotating plate 70 and detected at different times. Therefore, they do not interfere with each other.

  An arrangement example of the rotating plate 70 of the X-ray foreign object detection device 1 will be described with reference to FIGS.

  As for the arrangement example of the rotating plate 70, as shown in FIG. 6A, a plurality of X-ray sources X1, X2,..., Xn and a plurality of light receiving elements R1, R2,. , Rn, and a plurality of X-ray sources X1, X2,..., Xn and a plurality of light receiving elements R1, R2,..., Rn, as shown in FIG. A rotation plate 70 is provided in each of the X-ray passage areas between the two, and as shown in FIG. 6C, one rotation is provided between the two X-ray sources X1 and X2 and the two light receiving elements R1 and R2. A plate 70 may be provided, and similarly, a single rotary plate 70 may be provided between the two X-ray sources X3 and X4 and the two light receiving elements R3 and R4.

  FIG. 7 is a diagram illustrating a combination example of a light receiving element and a data detection unit of the X-ray foreign object detection device 1 with reference to FIGS.

  As for the combination of the light receiving element and the data detection unit, as shown in FIG. 7A, a pair is formed with each of the light receiving elements R1, R2,..., Rn after the light receiving elements R1, R2,. In addition to the configuration in which the data detection units D1, D2,..., Dn are provided, as shown in FIG. 7B, one data detection unit D1 is provided in the subsequent stage of the plurality of light receiving elements R1, R2,. It can be configured.

  As described above, the X-ray foreign object detection device 1 according to the present embodiment includes the X-ray generator 9 that generates X-rays and the X-ray detector 10 that receives the X-rays from the X-ray generator 9. The object to be inspected is irradiated with X-rays in the inspection space 22 between the X-ray generator 9 and the X-ray detector 10 and conveyed in a predetermined conveying direction, and the object to be inspected is based on the amount of transmission. An X-ray foreign matter detection apparatus 1 for determining the presence or absence of foreign matter in W, which is disposed at an upper portion of an examination space 22 and is provided at a position for receiving X-rays output from an X-ray generator 9 to improve the quality of radiation. Based on detection data corresponding to X-rays from the rotating plate 70 that rotates about the axis as the line quality switching means that sequentially switches and outputs and the rotating plate 70 detected by the X-ray detector 10. And a determination unit 48 for determining the presence or absence of the foreign matter.

  With this configuration, the X-rays output from the X-ray generator 9 are sequentially switched and output by the rotating plate 70 on which the X-rays rotate, so that the X-ray detector 10 is time-separated X-rays for each quality. Can receive. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  In addition, in the X-ray foreign object detection device 1 according to the present embodiment, the X-ray detector 10 outputs detection data for each X-ray quality to be detected, and for each X-ray quality output from the X-ray detector 10. And an image processing unit 44 that synthesizes the detected data and outputs the image data as one image data corresponding to the inspection object W. The determination unit 48 is based on the image data output from the image processing unit 44. The presence or absence of foreign matter in W is determined.

  With this configuration, X-rays having different radiation qualities are used, and the detection data from the X-ray detector 10 is combined to reduce the influence of the thickness of the inspection object W and obtain an image in which foreign matter is emphasized. be able to.

  Further, in the X-ray foreign object detection device 1 according to the present embodiment, the X-ray generator 9 outputs X-ray line sensors 51 and 52 as first and second X-ray sources that output X-rays having different radiation qualities. The rotating plate 70 is provided with shielding portions 71 that shield X-rays and transmission portions 72 that transmit X-rays alternately around the axis, and the X-ray line sensor 51 rotates by rotating around the axis. One X-ray output from each of the X-rays 52 is sequentially transmitted and the other X-rays are sequentially shielded so that the quality of the radiation is sequentially switched.

  With this configuration, the rotating rotary plate 70 sequentially transmits one X-ray output from each of the X-ray line sensors 51 and 52 and shields the other X-rays in sequence, whereby the X-ray detector 10. Can receive X-rays separated in time for each quality. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  The X-ray foreign object detection device 1 according to the present embodiment also includes a first filter unit 75 that transmits X-rays with a first quality through the rotating plate 70, and a first filter unit that transmits X-rays with a second quality. Two filter sections 76 are alternately provided around the axis, and the line quality is sequentially switched by rotating around the axis.

  With this configuration, the X-ray detector 10 can receive X-rays that are time-separated into a first radiation quality and a second radiation quality from the rotating rotating plate 70. Therefore, it is possible to prevent X-rays having different radiation qualities from interfering at the detection stage.

  Further, in the X-ray foreign object detection device 1 according to the present embodiment, one of the X-ray quality detected by the X-ray detector 10 is high energy X-ray and the other is low energy X-ray. It is characterized by.

  With this configuration, by using high-energy X-rays and low-energy X-rays, it is possible to reduce the influence of the thickness of the inspection object W and obtain an image in which foreign matter is emphasized.

  In addition, in the X-ray foreign object detection device 1 according to the present embodiment, the rotation direction of the part where the rotary plate 70 outputs X-rays having lower energy than the width in the rotation direction of the part outputting high-energy X-rays. Is characterized by a wide width.

  With this configuration, the time that the X-ray detector 10 receives low-energy X-rays is longer than the time that the X-ray detector 10 receives high-energy X-rays, and an X-ray image with high contrast can be obtained.

  Further, the X-ray foreign object detection device 1 according to the present embodiment includes a moving mechanism 74 that changes the position of the rotating plate 70 with respect to the X-ray generator 9, and the rotating plate 70 starts from an inner peripheral portion near the rotating shaft. The width of the transmission part 72 in the rotation direction becomes wider toward the outer peripheral part far from the rotation axis.

  With this configuration, by changing the position of the rotating plate 70 by the moving mechanism 74, it is possible to change the duty ratio of X-rays with different quality output from the rotating plate 70.

  In addition, the X-ray foreign object detection device 1 according to the present embodiment changes the timing at which the X-ray detector 10 outputs detection data, and validates the detection data output from the X-ray detector 10 at a predetermined timing. And a control unit 40.

  With this configuration, it is possible to reliably separate X-rays having different radiation qualities by changing the timing at which the detection data is output and enabling the detection data at a predetermined timing.

  As described above, the X-ray foreign object detection device according to the present invention has an effect that X-rays having different quality can be prevented from interfering at the detection stage, and a plurality of X-rays are applied to the inspection object. It is useful as an X-ray foreign object detection device that irradiates simultaneously.

DESCRIPTION OF SYMBOLS 1 X-ray foreign material detection apparatus 2 Conveyance part (conveyance means)
2a Belt surface 3 Detector 4 Case 5 Display 6 Drive motor 7 Carry-in port 8 Carry-out port 9 X-ray generator (X-ray generating means)
10 X-ray detector (X-ray detection means)
DESCRIPTION OF SYMBOLS 11 Box 16 Shielding curtain 21 Conveyance path 21a Ceiling part 22 Inspection space 30 X-ray tube 31 X-ray tube (X-ray source, high energy X-ray source)
32 X-ray tube (X-ray source, low-energy X-ray source)
40 control unit (output timing changing means, detection data validation means)
43 Storage Unit 44 Image Processing Unit (Image Composition Unit)
48 determination part (determination means)
49 Setting part 50, 51, 52 X-ray line sensor (X-ray detection means)
60, 61, 62 Data detector 70 Rotating plate (wire quality switching means)
71 Shielding portion 72 Transmission portion 73 Filter portion 74 Moving mechanism (rotating plate moving means)
75 First filter section (first transmission section)
76 Second filter section (second transmission section)
W Inspection object

Claims (8)

X-ray generation means (9) for generating X-rays, and X-ray detection means (10) for receiving X-rays from the X-ray generation means, and between the X-ray generation means and the X-ray detection means X-ray foreign matter that irradiates the inspection object (W) conveyed in the predetermined conveyance direction (Y) within the inspection space and determines the presence or absence of the foreign substance in the inspection object based on the amount of transmission A detection device (1) comprising:
A line quality that is arranged in the upper part of the examination space, is provided at a position to receive the X-rays output from the X-ray generation means, and is sequentially switched and output by a rotating plate (70) that rotates about an axis. Switching means (70);
Determination means (48) for determining the presence or absence of foreign matter in the inspection object based on the detection data corresponding to the X-rays from the radiation quality switching means detected by the X-ray detection means. A featured X-ray foreign object detection device. The X-ray detection means outputs detection data for each X-ray quality to be detected,
Image synthesizing means (44) for synthesizing the detection data for each of the radiation qualities output from the X-ray detection means and outputting as one image data corresponding to the inspection object;
The X-ray foreign object detection apparatus according to claim 1, wherein the determination unit determines the presence or absence of a foreign substance in the inspection object based on image data output from the image synthesis unit. The X-ray generation means includes first and second X-ray sources (31, 32) that output X-rays having different radiation qualities,
The radiation quality switching means includes a rotating part (71) that shields X-rays and a transmitting part (72) that transmits X-rays alternately on the rotating plate, and rotates about the axis. By sequentially transmitting one X-ray output from each of the first and second X-ray sources and sequentially shielding the other X-rays, the radiation quality is sequentially switched. The X-ray foreign material detection apparatus according to claim 1 or 2.   The radiation quality switching means includes a first transmission part (75) that transmits X-rays with a first quality to the rotating plate, and a second transmission part (76) that transmits X-rays with a second quality. 3. The X-ray foreign object detection device according to claim 1, wherein the X-ray foreign matter is alternately provided around the axis, and the line quality is sequentially switched by rotating around the axis.   The X-ray quality detected by the X-ray detection means is one of high-energy X-rays and the other is low-energy X-rays. X-ray foreign object detection device.   6. The rotation plate according to claim 5, wherein the rotation plate has a width in a rotation direction of a portion outputting the low energy X-rays larger than a width in a rotation direction of the portion outputting the high energy X-rays. X-ray foreign object detection device. A rotating plate moving means (74) for changing the position of the rotating plate with respect to the X-ray generating means;
4. The width of the transmission part in the rotation direction increases as the rotation plate moves from an inner peripheral part near the rotation axis to an outer peripheral part far from the rotation axis. X-ray foreign object detection device. Output timing changing means (40) for changing the timing at which the X-ray detection means outputs detection data;
The detection data validation means (40) for validating the detection data output from the X-ray detection means at a predetermined timing, The X according to any one of claims 1 to 7, further comprising: Wire foreign matter detection device.

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