JP2013186066A - X-ray inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray inspection device that enables continuous acquisition of many pieces of information from a plurality of articles.SOLUTION: An X-ray inspection device 100 comprises a conveyor unit 11, an X-ray radiation part 12, an X-ray detection part 13 and a rotary mechanism 15. The conveyor unit conveys an article. The X-ray radiation part is placed on a first side of the conveyor unit and radiates the article from the first side with an X-ray. The X-ray radiation part is placed on a second side and detects a transmission X-ray. The second side is a side that is opposite the first side. The transmission X-ray is an X-ray that has passed through the article. The rotary mechanism rotates the article around a vertical shaft.

Description

  The present invention relates to an X-ray inspection apparatus.

  2. Description of the Related Art Conventionally, X-ray inspection apparatuses that irradiate an article with X-rays and determine foreign matters mixed in the article based on X-rays transmitted through the article (transmitted X-rays) are known. In such an X-ray inspection apparatus, for example, as shown in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2009-80031), articles are conveyed in the horizontal direction by a conveyor unit. X-rays are irradiated from above the conveyor unit, and transmitted X-rays are detected below the conveyor unit. The X-ray inspection apparatus generates two-dimensional information of an article based on transmitted X-rays, and determines a foreign object based on the two-dimensional information.

  Incidentally, the X-ray inspection apparatus as described above determines a foreign object using a threshold set corresponding to the type of article and two-dimensional information. Here, if the set threshold value is not an appropriate value, an erroneous determination may be made regarding the presence or absence of foreign matter. Therefore, even if it is determined that there is a foreign object based on the two-dimensional information, it is preferable to obtain information on the article from various angles and perform a more detailed inspection based on the three-dimensional information. However, in the X-ray inspection apparatus as described above, if information is to be acquired from an article in a multifaceted manner, a gripping unit for gripping the article and rotating it around a horizontal axis is necessary. In addition, since it is necessary to grip the article to be inspected by the gripping unit, it is difficult to perform a detailed inspection on a plurality of articles.

  An object of the present invention is to provide an X-ray inspection apparatus that facilitates detailed inspection of a plurality of articles.

  The X-ray inspection apparatus according to the present invention includes a conveyor unit, an X-ray irradiation unit, an X-ray detection unit, and a rotation mechanism. The conveyor unit conveys articles. The X-ray irradiation unit is disposed on the first side of the conveyor unit and irradiates the article with X-rays from the first side. The X-ray detection unit is disposed on the second side and detects transmitted X-rays. The second side is a side facing the first side. The transmitted X-ray is an X-ray that has passed through the article. The rotation mechanism rotates the article around the vertical axis. Thereby, the detailed test | inspection about a some article | item can be performed easily.

  Moreover, it is preferable that a rotation mechanism rotates the article | item on a conveyor unit. Thereby, a lot of information can be acquired from an article, without stopping conveyance of an article.

  Further, it is preferable that the rotating mechanism further moves the article on the conveyor unit upward in the vertical direction. Thereby, a lot of information can be acquired from the whole article.

  Furthermore, the X-ray irradiation unit irradiates the article with X-rays in the X-ray irradiation space, and the rotation mechanism preferably rotates the article when the article is in the X-ray irradiation space. Thereby, the three-dimensional information about the article can be acquired.

  Moreover, it is preferable that the X-ray irradiation unit irradiates the article with X-rays in the X-ray irradiation space, and the rotation mechanism moves the article upward in the vertical direction while rotating the article when the article is in the X-ray irradiation space. Thereby, the three-dimensional information about the article can be acquired efficiently.

  Moreover, it is preferable that a conveyor unit has a table which mounts articles | goods and a rotation mechanism rotates a table. Thereby, the article can be rotated in a state in which the posture is stabilized.

  The X-ray detection unit is preferably a flat panel sensor. Thereby, a lot of information can be acquired in a short time.

  According to the X-ray inspection apparatus according to the present invention, detailed inspection of a plurality of articles can be easily performed.

It is a block diagram which shows the structure of the X-ray inspection apparatus which concerns on one Embodiment of this invention. 1 is a schematic perspective view of an X-ray inspection apparatus according to an embodiment of the present invention. 1 is a schematic plan view of an X-ray inspection apparatus according to an embodiment of the present invention. 1 is a schematic side view of an X-ray inspection apparatus according to an embodiment of the present invention. 1 is a schematic side view of an X-ray inspection apparatus according to an embodiment of the present invention. It is a figure which shows the flow of a process in the X-ray inspection apparatus which concerns on one Embodiment of this invention. It is a schematic perspective view of the X-ray inspection apparatus which concerns on the modification D of this invention. It is a schematic plan view of the X-ray inspection apparatus which concerns on the modification D of this invention. It is a schematic side view of the X-ray inspection apparatus which concerns on the modification D of this invention.

  Hereinafter, an X-ray inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(1) Schematic Description of X-ray Inspection Apparatus FIG. 1 is a block diagram for explaining the configuration of an X-ray inspection apparatus 100 according to an embodiment of the present invention. The X-ray inspection apparatus 100 determines whether or not foreign matter is mixed in the article G by irradiating the article G that is continuously conveyed with X-rays. Specifically, the X-ray inspection apparatus 100 continuously detects transmission X-rays of each article G from a plurality of articles G, and based on data relating to the transmission X-rays, three-dimensional data (sinogram, tomographic image) of the article G , And stereoscopic image). Furthermore, the X-ray inspection apparatus 100 determines the presence or absence of foreign matter mixed in the article G based on the sinogram, tomographic image, and stereoscopic image of the article G.

  As shown in FIG. 1, the X-ray inspection apparatus 100 includes a transport mechanism (conveyor unit) 11, an X-ray irradiator (X-ray irradiator) 12, a line sensor (X-ray detector) 13, a monitor 14, and a rotating mechanism 15. And a control device 16. The X-ray inspection apparatus further includes a shield box (not shown). Hereafter, each structure with which an X-ray inspection apparatus is provided is demonstrated in detail.

(2) Detailed description of X-ray inspection apparatus (2-1) Shield box The shield box is a box that houses the transport mechanism 11, the X-ray irradiator 12, the line sensor 13, the rotation mechanism 15, and the control device 16. The shield box prevents leakage of X-rays to the outside. A monitor 14 is attached to the front of the shield box. Furthermore, a key insertion slot, a power switch, and the like are arranged on the front face of the shield box. A door is provided on the side of the shield box. The door is used to put in and out the article G with respect to the shield box.

(2-2) Transport Mechanism The transport mechanism 11 is a mechanism that transports the article G within the shield box. Specifically, the transport mechanism 11 moves the article G in the plane so that the article G turns in the shield box (see FIG. 2).

  As shown in FIG. 1, the transport mechanism 11 is mainly composed of a plane moving member 11a, a rotary table 11b, and a transport drive motor 11c.

  The plane moving member 11a is a member that conveys the article G in a plane in the shield box. Specifically, the plane moving member 11a turns the article G to move to the X-ray irradiation range X, and further away from the irradiation range X. The plane moving member 11a is an annular member that constitutes the conveyance path of the article G (see FIG. 2). The planar moving member 11a has a planar portion that is continuous in an annular shape. The plane moving member 11a is driven by the transport drive motor 11c and turns in the plane.

  The turntable 11b is a member that rotates the article G, which has been moved to the irradiation range X by the plane moving member 11a, within the irradiation range X. The turntable 11b is a table on which the article G is placed. The turntable 11b constitutes a part of the plane portion of the plane moving member 11a. Therefore, the rotary table 11b moves in the plane as the plane moving member 11a turns in the plane. A plurality of rotary tables 11b are arranged on the plane moving member 11a. The plurality of turntables 11b are arranged on the plane moving member 11a with a predetermined interval. The rotary table 11b has teeth cut on the side surfaces. The teeth on the side surface of the rotary table 11b have a shape that meshes with the side surface of a contact member 15a of the rotation mechanism 15 described later. The rotation table 11b rotates around the vertical axis with the center of the rotation table 11b as a reference and moves in the vertical axis direction by driving the rotation mechanism 15 (see FIGS. 3B and 3C). In addition, while the turntable 11b is rotating, the conveyance drive motor 11c stops driving the planar moving member 11a. That is, the turntable 11b rotates the article G around the vertical axis without changing the position in the plane.

(2-3) X-ray irradiator The X-ray irradiator 12 irradiates the article G with X-rays. As shown in FIG. 2 and FIGS. 3A to 3C, the X-ray irradiator 12 is disposed on the side of the conveyance path of the article G. That is, the X-ray irradiator 12 irradiates the article G with X-rays from the side. As shown in FIG. 3A, the X-ray irradiation range X extends in a fan shape in the horizontal direction in plan view.

(2-4) Line Sensor The line sensor 13 is a member that detects X-rays emitted from the X-ray irradiator 12. As shown in FIGS. 2 and 3A to 3C, the line sensor 13 is disposed on the side of the conveyance path of the article G. Specifically, the line sensor 13 is disposed at a position facing the X-ray irradiator 12 across the conveyance path of the article G. The line sensor 13 is mainly composed of a large number of X-ray detection elements 13a. Specifically, as shown in FIGS. 2 and 3A, a large number of X-ray detection elements 13a are arranged in a line in the horizontal direction. Each X-ray detection element 13a outputs an X-ray transmission signal based on the X-ray transmitted through the article G. In other words, the X-ray transmission signal outputs an X-ray transmission signal corresponding to the intensity of the transmitted X-ray. The intensity of the transmitted X-ray depends on the magnitude of the transmitted X-ray dose (transmitted X-ray dose).

  Further, the line sensor 13 also functions as a sensor for detecting the timing when the article G as a specimen passes through the fan-shaped X-ray irradiation range X. That is, when the article G conveyed by the conveyance mechanism 11 reaches the front position (irradiation range X) of the line sensor 13, the line sensor 13 transmits an X-ray transmission signal (first signal) indicating a voltage equal to or lower than a predetermined threshold. ) Is output. Further, when the article G passes the irradiation range X, the line sensor 13 outputs an X-ray transmission signal (second signal) indicating a voltage exceeding a predetermined threshold. The presence or absence of the product G in the irradiation range X is detected by inputting the first signal and the second signal to the control device 16 described later.

(2-5) Monitor The monitor 14 is a liquid crystal display. The monitor 14 displays a screen that prompts the operator to input inspection parameters and the like necessary for the inspection. The monitor 14 also has a touch panel function and accepts input of inspection parameters and the like from the operator.

(2-6) Rotation Mechanism The rotation mechanism 15 is a mechanism that rotates the rotation table 11b of the transport mechanism 11 within the irradiation range X. As shown in FIG. 1, the rotation mechanism 15 mainly includes a contact member 15a and a rotation drive motor 15b. The contact member 15a is a member that contacts the side surface of the turntable 11b. The contact member 15a is disposed outside (side) the transport path. Teeth are cut on the side surface of the contact member 15a. As described above, the teeth on the side surface of the contact member 15a are configured to mesh with the teeth on the side surface of the rotary table 11b. Further, the contact member 15a is arranged so as to mesh with the side surface of the turntable 11b when the turntable 11b reaches the irradiation range X.

  The contact member 15a is driven by a rotational drive motor 15b. Specifically, when contact between the contact member 15a and the turntable 11b is detected by a sensor (not shown), the rotation drive motor 15b drives the contact member 15a. The rotation drive motor 15b rotates the contact member 15a so that the article G rotates 360 ° around the vertical axis in the irradiation range X. Further, the rotation drive motor 15b moves the contact member 15a up and down. Specifically, the rotation drive motor 15b moves the contact member 15a by a predetermined distance upward in the vertical axis direction within the irradiation range X so that X-rays are irradiated to the entire height direction of the article G. That is, the rotation drive motor 15b moves the contact member 15a to the upper position while rotating it around the vertical axis. Thereby, the article G moves across the direction in which the X-rays spread while rotating 360 ° in the irradiation range X (see FIGS. 3B and 3C). The rotation drive motor 15b controls the contact member 15a so that the rotation of the contact member 15a and the movement to the upper position are completed at the same time. That is, when the contact member 15a rotates the article G by 360 °, the movement of the article G from the lower position to the upper position ends. Thereafter, the rotation drive motor 15b moves the contact member 15a to a lower position while rotating the contact member 15a in the reverse direction.

(2-7) Control Device The control device 16 is mainly composed of ROM, RAM, HDD (hard disk), and CPU. As shown in FIG. 1, the control device 16 is connected to a transport drive motor 11c, an X-ray irradiator 12, a line sensor 13, a monitor 14, a rotation drive motor 15b, and the like. Further, the control device 16 acquires data related to the rotation speed of the transport drive motor 11c from an encoder (not shown), and grasps the moving distance of the article G in the plane based on the data. Furthermore, the control device 16 acquires data related to the rotation speed of the rotation drive motor 15b from an encoder (not shown), and based on the data, the rotation angle around the vertical axis of the rotary table 11b (article G) and the movement distance in the vertical axis direction. To figure out. In addition, as described above, the control device 16 receives the X-ray transmission signal output from the line sensor 13 to detect the timing when the article G reaches the irradiation range X and the timing when it passes through the irradiation range X. .

  The control device 16 generates three-dimensional data of the article G based on the X-ray (transmission X-ray) detected by the line sensor 13. Specifically, the control device 16 generates a sinogram, a tomographic image, and a stereoscopic image of the article G based on the transmitted X-rays. Further, the control device 16 performs foreign matter determination (existence of foreign matter, location of mixed foreign matter, etc.) of the article G based on the sinogram, tomographic image, and stereoscopic image of the article G, and the determination result is displayed on the monitor 14. indicate.

(3) Process Flow Next, the process flow of foreign matter determination in the X-ray inspection apparatus 100 will be described with reference to FIG.

  First, in step S11, it is determined whether or not the article G has reached the irradiation range X. Specifically, it is determined whether or not a signal indicating that the article G has been detected is received from the line sensor 13. In step S11, the process waits until the article G reaches the irradiation range X. When the article G reaches the irradiation range X, the process proceeds to step S12.

  In step S12, transmitted X-rays about the article G are detected. Further, the rotation drive motor 15b is driven. Specifically, when the article G reaches the irradiation range X, the line sensor 13 outputs an X-ray transmission signal based on the X-rays transmitted through the article G. Further, the rotary drive motor 15b is driven, and the article G rotates around the vertical axis in the irradiation range X and moves upward in the vertical axis direction. As a result, transmitted X-rays for X-rays irradiated on the article G from many directions are detected. Thereafter, the process proceeds to step S13.

  In step S13, it is determined whether or not the turntable 11b has rotated 360 °. Specifically, data relating to the rotational speed of the rotary drive motor 15b is acquired from the encoder, and the rotational angle around the vertical axis of the rotary table 11b is grasped based on the data. In step S13, the process waits until the turntable 11b rotates 360 °. When the turntable 11b rotates 360 °, the process proceeds to step S14.

  In step S14, three-dimensional data is generated based on the data (X-ray transmission signal) relating to the transmission X-rays of the article G obtained by rotating the article G by 360 °. Specifically, as described above, a sinogram, a tomographic image, and a stereoscopic image of the article G are generated. Thereafter, the process proceeds to step S15.

  In step S15, foreign matter determination is performed based on the three-dimensional data of the article G. Specifically, the presence / absence of a foreign substance in the article G, and the location of the foreign substance when the foreign substance is mixed in the article G are determined. Thereafter, the process proceeds to step S16.

  In step S <b> 16, the foreign substance determination result for the article G is displayed on the monitor 14. For example, as each article G passes, the monitor 14 displays the determination result of the article G (“OK” or “NG”, the location of the mixed foreign matter in the case of NG, etc.).

(4) Features (4-1)
In the X-ray inspection apparatus 100 according to the embodiment, the article G is transported by the transport mechanism 11. The X-ray irradiator 12 and the line sensor 13 are arranged at opposing positions in the width direction of the transport path. Specifically, the X-ray irradiator 12 is disposed on the first side in the width direction of the conveyance path of the article G, and the line sensor 13 is a second position that faces the first side. Located on the side. The X-ray irradiator 12 emits fan-shaped X-rays extending in the horizontal axis direction (see FIGS. 3A to 3C). The article G is transported to the X-ray irradiation range X by the transport mechanism 11, and ascends while rotating 360 ° around the vertical axis in the irradiation range X by the rotary table 11b.

  In the conventional X-ray inspection apparatus, X-rays are irradiated from the upper side in the vertical direction to the article conveyed by the conveyor unit, and transmitted X-rays of the article are detected from the lower side in the vertical direction. In such an X-ray inspection apparatus, two-dimensional data (planar image) of an article is generated, and foreign matter determination is performed based on the two-dimensional data. In foreign matter determination by the X-ray inspection apparatus, a threshold value for foreign matter determination is set corresponding to the type of article. Therefore, when the set threshold value is not appropriate, there is a possibility that it is erroneously determined that foreign matters are mixed in the article. Therefore, in order to perform more accurate foreign object determination, it is preferable to use the three-dimensional information of the article G. Here, similarly to the conventional X-ray inspection apparatus, the article is irradiated with X-rays from the upper side in the vertical direction and the transmitted X-rays of the article are detected on the lower side in the vertical direction. When generating the three-dimensional data, it is necessary to rotate the article around the horizontal axis. Therefore, it is necessary to grip the article to be inspected by a gripping part that enables rotation around the horizontal axis. That is, each time the foreign object determination of each article is performed, the article to be inspected needs to be held by the holding portion. Therefore, it becomes complicated to generate three-dimensional data for a large number of articles.

  However, the X-ray inspection apparatus 100 according to the embodiment irradiates the article G with X-rays from the side. Further, in order to generate the three-dimensional data of the article G, the article G is rotated around the vertical axis while moving in the vertical axis direction. Therefore, since it is not necessary to cause the article G to be gripped by the gripping portion, foreign matter determination can be easily performed even when a plurality of articles G are targeted for detailed inspection.

(4-2)
In the X-ray inspection apparatus 100 according to the above-described embodiment, the rotary table 11b constitutes a part of the plane portion of the plane moving member 11a. A plurality of rotary tables 11b are arranged on the plane moving member 11a. As a result, a plurality of articles G are put in the shield box, and foreign matter determination of the plurality of articles G can be performed continuously.

(4-3)
In the X-ray inspection apparatus 100 according to the above-described embodiment, the article G rotates 360 ° on the turntable 11b. For example, when the article G is composed of a packaging material and contents, and the contents are canned foods or snacks that move freely inside the packaging material, the contents move inside the packaging material by rotation around the horizontal axis. However, it is difficult to obtain an accurate determination result. However, the X-ray inspection apparatus 100 according to the above embodiment rotates in a state where the article G is placed on the rotary table 11b. Thereby, since the attitude | position of goods is stabilized, it becomes possible to suppress that a content moves inside a packaging material, and to acquire exact information.

(5) Modification (5-1) Modification A
In the X-ray inspection apparatus 100 according to the above-described embodiment, a plurality of articles G are placed in advance in a shield box, and foreign matter determination is continuously performed on the plurality of articles G. Here, the X-ray inspection apparatus 100 may be configured to be connectable to other conveyor units. Specifically, when the X-ray inspection apparatus 100 is viewed from the front, a carry-in port and a carry-out port for the article G are formed in the left-right direction of the shield box. Warm for preventing X-ray leakage shall be attached to the carry-in port and the carry-out port. In addition, the transport mechanism 11 transports the article G from the carry-in port toward the carry-out port, and the planar moving member 11a has a transport path through which the product G can move from the carry-in port through the irradiation range X to the carry-out port. It shall be a member which comprises. The upstream conveyor unit is connected to the carry-in side of the planar moving member 11a, and the upstream conveyor unit conveys the article G to the X-ray inspection apparatus 100 at a predetermined time interval or distance interval, and automatically the article G May be configured to be placed on the rotary table 11b. Thereby, the foreign substance determination based on three-dimensional data can be continuously performed for many articles G.

  Furthermore, a sorting device may be connected to the X-ray inspection apparatus 100. Specifically, the sorting device is configured to be connected to the carry-out side of the planar moving member 11a and sort the articles G according to the result of foreign matter determination by the X-ray inspection device 100. Thereby, the distribution process of the articles | goods G can be performed automatically.

(5-2) Modification B
In the above embodiment, the rotary table 11b is rotationally driven at the timing when the contact member 15a contacts the rotary table 11b. Here, the rotational drive of the turntable 11b may be the timing when the article G is detected by the line sensor 13.

(5-3) Modification C
Moreover, in the said embodiment, the contact member 15a is rotationally driven by the rotational drive motor 15b, and the rotation table 11b which contacts the contact member 15a rotates by rotation of the contact member 15a. Here, the rotary table 11b may be rotated by a configuration different from the contact member 15a. That is, the rotary table 11b may have another configuration as long as the article G is rotated 360 ° within the irradiation range X.

(5-4) Modification D
In the above-described embodiment, the X-ray inspection apparatus 100 includes the line sensor 13, but may include a flat panel sensor 23 instead of the line sensor 13 (see FIG. 5). The flat panel sensor 23 includes a large number of X-ray detection elements 23a. Specifically, the flat panel sensor 23 is a panel-shaped sensor in which a large number of X-ray detection elements 23a are arranged in the vertical direction and depth direction of the paper surface as shown in FIG. At this time, the X-ray irradiator 12 is configured such that the X-ray irradiation range X extends over the entire area of the flat panel sensor 23. Specifically, the X-ray irradiation range X extends in the width direction of the flat panel sensor 23 in plan view as shown in FIG. 6A, and the height direction of the flat panel sensor 23 in side view as shown in FIG. 6B. It also extends in the (vertical direction). Further, the contact member 15 a is replaced with the contact member 25. The contact member 25 is disposed at a side position of the plane moving member 11a and in contact with the side surface of the turntable 11b that enters the irradiation range X. The contact member 25 has teeth cut on a surface (side surface) that contacts the side surface of the rotary table 11b. The teeth are shaped to mesh with the side surface of the turntable 11b. The side surface of the contact member 25 extends in the length direction of the flat panel sensor 23. When the rotary table 11b on which the article G is placed by the plane moving member 11a reaches the X-ray irradiation range X, the side surface of the rotary table 11b meshes with the side surface of the contact member 25. The rotary table 11b moves in the plane with the movement of the plane moving member 11a in a state where the side surface meshes with the side surface of the contact member 25. That is, the rotary table 11b rotates around the vertical axis while moving in the plane. In other words, the X-ray inspection apparatus 100 can generate three-dimensional data about the article G by rotating the article G without stopping the movement of the article G in the plane by the plane moving member 11a. Thereby, the number of inspection objects per unit time can be improved as compared with the X-ray inspection apparatus according to the embodiment.

11 Transport mechanism (conveyor unit)
11a Plane moving member 11b Rotary table 11c Transport drive motor 12 X-ray irradiator (X-ray irradiator)
13 Line sensor (X-ray detector)
14 Monitor 15, 25 Rotating mechanism 15 a, 25 Contact member 15 b Rotation drive motor 16 Control device 23 Flat panel sensor (X-ray detector)
100 X-ray inspection equipment

JP 2009-80031 A

Claims (7)

A conveyor unit for conveying articles;
An X-ray irradiation unit that is disposed on a first side of the conveyor unit and irradiates the article with X-rays from the first side;
An X-ray detector that is disposed on a second side opposite to the first side and detects transmitted X-rays that are the X-rays that have passed through the article;
A rotation mechanism for rotating the article around a vertical axis;
Comprising
X-ray inspection equipment. The rotating mechanism rotates the article on the conveyor unit;
The X-ray inspection apparatus according to claim 1. The rotating mechanism further moves the article on the conveyor unit vertically upward.
The X-ray inspection apparatus according to claim 2. The X-ray irradiation unit irradiates the article with the X-ray in an X-ray irradiation space,
The rotating mechanism rotates the article when the article is in the X-ray irradiation space.
The X-ray inspection apparatus according to claim 2. The X-ray irradiation unit irradiates the article with the X-ray in an X-ray irradiation space,
The rotating mechanism moves the article upward in the vertical direction while rotating the article when the article is in the X-ray irradiation space.
The X-ray inspection apparatus according to claim 3. The conveyor unit has a table on which the article is placed,
The rotation mechanism rotates the table;
The X-ray inspection apparatus according to claim 2. The X-ray detection unit is a flat panel sensor.
The X-ray inspection apparatus according to claim 1.

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