JP4814197B2 - X-ray foreign object detection device - Google Patents

Description

  The present invention relates to an X-ray foreign object detection apparatus that irradiates an inspection object on a conveyance surface with X-rays and detects foreign substances mixed in the inspection object based on the amount of transmission.

  A conventional X-ray foreign matter detection apparatus irradiates an object to be inspected conveyed by a conveying means such as a conveyer with X-rays from directly above vertically downward, and transmits X-rays with an X-ray detector provided below the X-ray detector. A foreign object in an inspection object is detected by receiving a line. However, when the inspection object W is, for example, a box packed with stick-shaped frozen confectionery C or the like, the X-ray transmission distance becomes longer when X-rays are irradiated from directly above, and the detection accuracy may decrease. (See FIG. 5 (a)).

Moreover, the X-ray foreign material detection apparatus disclosed in Patent Document 1 below irradiates X-rays obliquely from above on an inspection object conveyed in the horizontal direction by a conveyance mechanism (conveyance conveyor). For example, when foreign matter detection is performed on the inspected object W (a box packed with stick-shaped frozen confections C) as described above using this apparatus, each frozen confection C is compared with a case where X-rays are irradiated vertically downward. The X-ray transmission distance is shortened, so that the detection accuracy is improved (see FIG. 5B).
JP 2004-317184 A

  However, in the above-described conventional X-ray foreign object detection device (Patent Document 1), an X-ray generator that irradiates X-rays as shown in FIG. 5B and X-rays emitted from the X-ray generator are used. Since the receiving X-ray detector is disposed opposite to the inside of the housing in an oblique direction, a large shielding space for X-ray irradiation in the housing has to be provided, resulting in a problem that the apparatus becomes large.

  Moreover, in the X-ray foreign material detection apparatus of the said patent document 1, the irradiation angle of X-rays can be changed optimally according to the size etc. of a to-be-inspected object. In this case, as can be seen from FIG. 5B, the position of the X-ray generator for irradiating X-rays must be changed so that the position of the X-ray detector for receiving X-rays must be changed at the same time. The work of changing the angle has been complicated.

  Therefore, the present invention has been made in view of the above situation, and the X-ray irradiation angle can be easily optimized by changing the X-ray irradiation angle with respect to the inspection object by a simple operation of inclining the conveying means. In addition, since the positions of the X-ray generator and the X-ray detector are fixed, there is no need to provide a large shielding space, and therefore the X-ray foreign object detection device does not increase in size. It is aimed.

Next, means for solving the above problems will be described with reference to the drawings corresponding to the embodiments.
The X-ray foreign matter detection device according to claim 1 of the present invention includes a transport means 5 for transporting the inspection object W on the transport surface in a predetermined transport direction Y,
An X-ray generator 18 that emits X-rays toward the inspection object W conveyed on the conveyance surface;
An X-ray foreign object detection device comprising: an X-ray detector 19 disposed opposite to the X-ray generator 18 across the transport surface and receiving the X-rays transmitted through the inspection object W on the X-ray detection surface In 1,
The transport means 5 includes a transport conveyor 6 through which a transport belt 9 forming the transport surface is circulated , and is provided so as to be tiltable so that an angle of the transport surface with respect to the X-ray detection surface can be changed. A guide belt 14 that forms a guide surface orthogonal to the conveyance surface is circulated at the same speed as the conveyance belt 9, and is inclined integrally with the conveyance conveyor 6 to support the side surface of the object W to be inspected. A guide conveyor 12 that guides the conveyance of the inspection object W is provided.

The X-ray foreign matter detection apparatus according to claim 2 is characterized in that the transport conveyor 6 and the guide conveyor 12 have a common drive source 11.

The X-ray foreign matter detection apparatus according to a third aspect is characterized by including an actuator 17 for inclining the conveying means 5.

The X-ray foreign matter detection device according to claim 4 includes a sensor for detecting the inspection object W carried into the transport means 5,
The actuator 17 is operated based on a detection signal from the sensor.

According to the X-ray foreign object detection device of the present invention, the conveying means is provided so as to be inclined, so that the X-ray irradiation angle on the object to be inspected can be changed by a simple operation of inclining the conveying means. it can. This makes it possible to easily optimize the X-ray irradiation angle according to the size of the inspection object. Further, in this case, since the positions of the X-ray generator and the X-ray detector are fixed, it is not necessary to provide a large shielding space in the housing, and thus the apparatus is not increased in size. Furthermore, since the inspection object is supported by the guide conveyor when the conveying means is inclined, it is possible to prevent the inspection object from falling when the conveying means is inclined.

In addition , when the conveying means is inclined, the box-shaped object to be inspected is conveyed not only by the conveying conveyor but also by a guide conveyor that is driven at the same speed as the conveying conveyor. Can be done.

According to the X-ray foreign object detection device of the second aspect , in addition to the effect of suppressing the number of parts, the conveyor and the guide conveyor can be driven synchronously.

According to the X-ray foreign object detection device of the third aspect , the tilting operation of the conveying means can be automated.

According to the X-ray foreign object detection apparatus of the fourth aspect , the conveyance means can be automatically inclined as the inspection object is carried into the conveyance means.

Embodiments of the present invention will be specifically described below with reference to the drawings.
FIG. 1A is a front view of an X-ray foreign object detection apparatus according to the present invention in a normal state, FIG. 1B is a side view thereof, FIG. 2A is a front view of the apparatus when the conveying means is inclined, and FIG. Is a side view, FIG. 3 is an explanatory view of the inclined structure of the conveying means, and FIGS. 4 to 6 are perspective views of the inclined operation of the conveying means.

  The X-ray foreign object detection device of this embodiment is provided in a part of a production line, irradiates an object to be transported with X-rays, and mixes in the object to be inspected based on the amount of transmission. It detects foreign matter such as metal, glass, stone, and synthetic resin material.

  In addition, the object to be inspected for foreign matter detection in this embodiment is, for example, a substantially rectangular box filled with stick-shaped frozen desserts (see FIG. 4 and the like).

  As shown in FIGS. 1 and 2, this embodiment includes a box-shaped housing 2 that is a main body of the apparatus 1. The housing 2 is supported on the installation surface by four legs 3. Furthermore, the housing | casing 2 is formed using a radiation protective material so that a harmful amount of X-rays may not leak outside from the inside. The front surface of the housing 2 is open, and a door 4 that can be opened and closed for closing the front opening is provided on the front surface of the housing 2.

  As shown in FIGS. 1 and 2, the conveying means 5 is provided so as to substantially penetrate the housing 2 in the horizontal direction, and transfers the inspection object W carried from the preceding conveyor to a predetermined conveying direction Y (horizontal direction). ), Passes through the inside of the housing 2, and is further carried out to a subsequent conveyor.

  As shown in FIGS. 3 to 6, the conveying means 5 is substantially constituted by a conveying conveyor 6 and a guide means 12. The conveyor 6 (belt conveyor) includes a pair of main rollers 7 and 7 and a pair of sub-rollers 8 and 8 that are wound around an endless belt 9 and conveys an object W to be inspected. Is forming. A frame 10 is provided between the main roller 7 and the sub roller 8 so as to connect the main and sub rollers 7 and 8. Furthermore, one of the pair of main rollers 7 and 7 is connected to a drive motor 11 as a drive source.

  The guide means 12 is composed of a guide conveyor (belt conveyor), in which an endless belt 14 is wound around a pair of rollers 13, 13 is provided on one outer portion of the conveyor 6, and the conveyor 6 Are provided substantially perpendicular to the transport surface. Moreover, the guide conveyor 12 forms the conveyance surface orthogonal to the conveyance surface of the conveyance conveyor 6 so that the side surface of the box-shaped to-be-inspected object W may be supported. Furthermore, one of the pair of rollers 13 and 13 is connected to the drive motor 11 as a drive source. In the drive motor 11, a bevel gear 15 is provided on the drive shaft 11 a, and a bevel gear 15 having the same diameter that meshes with the bevel gear 15 is provided on the roller 13 of the guide means 12. Thereby, both the conveyors 6 and 12 can be driven synchronously.

  Further, as shown in FIG. 3 in particular, the conveying means 5 is provided with a base end shaft 16 on one side (the side on which the guide conveyor 12 is provided), and this is used as an axis for the conveying surface of the conveying conveyor 6. It is provided so as to be tiltable so that the angle can be changed. An actuator 17 (for example, an air cylinder) for tilting the transport unit 5 is provided in the vicinity of the base end shaft 16 of the transport unit 5.

  Although not shown, a pair of sensors composed of a light projecting and light receiving sensor for detecting the inspection object W carried into the transport conveyor 6 (transport means 5) is provided at the carry-in end portion of the transport conveyor 6. It has been. The pair of sensors can detect the carry-in of the inspection object W by being opposed to each other in a direction orthogonal to the conveyance direction Y. Further, the pair of sensors outputs a signal to a control unit (not shown) that controls the driving of the actuator 17 when the inspection object W is carried in, and operates the actuator 17.

  Next, the optical system of this embodiment will be described. As shown in FIGS. 1 and 2, an X-ray generator 18 and an X-ray detector 19 are provided in the housing 2. The X-ray generator 18 is provided on the upper portion of the housing 2, and an object to be inspected that has been transported by the transport means 5 in which an X-ray tube that generates X-rays is immersed in insulating oil in a metal box. X-rays are irradiated toward W. In addition, the aspect of the X-ray irradiated from the X-ray generator 18 becomes a surface shape orthogonal to the conveyance direction Y, and the surface has a substantially triangular shape that extends downward.

  The X-ray detector 19 is provided in the lower part of the housing 2 and is disposed opposite to the X-ray generator 18 with the transport surface of the transport conveyor 6 interposed therebetween. The X-ray detector 19 includes a line sensor in which a photodiode and a large number of light receiving elements (not shown) each including a scintillator disposed on the photodiode are arranged in a line perpendicular to the transport direction Y.

  In such a configuration, the X-ray generator 18 irradiates the inspection object W transported on the transport surface of the transport conveyor 6 from the X-ray generator 18 and transmits the inspection object W along with the X-ray irradiation. The incoming X-ray is converted into light by the scintillator of the X-ray detector 19. The light converted by the scintillator is received by a photodiode, further converted into an electric signal, and output to an external computer or the like. Then, the output from the X-ray detector 19 is compared with a preset threshold value for each type of foreign matter, and based on the result, the foreign matter mixed in the inspection object W is detected.

From here, with reference to FIGS. 4-6, the inclination operation | movement of a conveyance means is demonstrated.
First, as shown in FIG. 4, before the inspection object W is carried into the conveyance means 5 from the preceding conveyor, the inclination angle of the conveyance means 5 (the conveyance surface of the conveyance conveyor 6 where the inspection object W is conveyed) The angle of the X-ray detector with respect to the X-ray detection surface is 0 ° (horizontal state).

  Next, as shown in FIG. 5, when the inspection object W is carried into the conveying means 5 from the carry-in end portion thereof from the preceding conveyor, it is detected by a sensor (not shown) and receives a signal from the sensor to receive the conveying means 5. Starts the tilting operation so that the angle becomes a predetermined angle θ (an optimum angle corresponding to the size of the object to be inspected). At this time, the conveying means 5 may be at a predetermined angle θ until the inspection object W reaches at least the X-ray irradiation position. Further, the descending side surface of the inspection object W inclined with the inclination of the conveying means 5 is conveyed and guided while being supported by the guide conveyor 12. Since the conveyor 6 and the guide conveyor 12 are driven synchronously, the circulation speeds of the belts 9 and 14 are equal.

  Next, when the inspection object W passes the X-ray irradiation position, the inclined conveying means 5 gradually returns to the horizontal state, and when the inspection object W reaches the unloading end portion, it becomes a complete horizontal state.

  Then, as shown in FIG. 6, the inspection object W is carried out from the conveying means 5 in the horizontal state onto the subsequent conveyor, and the conveying means 5 is in a standby state until the next inspection object W is carried in. Thereafter, the transport unit 5 repeats the above-described operation.

  According to the embodiment described above, since the conveying means 5 is provided so as to be inclined, the X-ray irradiation angle with respect to the inspection object W can be changed by a simple operation of inclining the conveying means 5, and the inspection object. The X-ray irradiation angle corresponding to the size of W can be easily optimized. Further, in this case, since the positions of the X-ray generator 18 and the X-ray detector 19 are fixed, it is not necessary to provide a large shielding space in the housing 2, and thus the apparatus 1 is not increased in size. Further, since the inspection object W is supported by the guide conveyor 12 when the conveying means 5 is inclined, the inspection object W can be prevented from falling when the conveying means 5 is inclined. Furthermore, it is possible to smoothly carry the inspection object W when inclined.

  Moreover, by driving the conveyor 6 and the guide conveyor 12 with a common drive motor 11, the number of parts can be reduced and both conveyors 6, 12 can be driven synchronously.

  Further, when the inspection object W is carried into the conveying means 5, it is detected by a sensor, and the conveying means 5 can be automatically tilted by the actuator.

  In the above-described embodiment, the transport unit 5 repeats the tilting operation while the inspection object W is transported. For example, the transport unit 5 is tilted at a predetermined angle, and the front stage and the rear stage. The conveyor may be configured to be tilted. According to such a configuration, since the inspection object is inclined at a predetermined angle at the X-ray irradiation position, the same effect as described above can be obtained.

  Although not described in the above-described embodiment, an X-ray shielding member is provided on the side of the housing 2 so that X-rays do not leak from the opening serving as the entrance / exit of the inspection object W. The X-ray shielding member needs to be formed so as to be compatible with the conveying means 5 that performs the tilting operation. For example, the X-ray shielding member may be configured to have a shape that protrudes long in the conveying direction Y. Anything that does not interfere is acceptable.

(A) It is the front view of the normal time of the X-ray foreign material detection apparatus by this invention. (B) It is a side view in the normal time of the X-ray foreign material detection apparatus by this invention. (A) It is a front view at the time of the inclination of the conveyance means of the X-ray foreign material detection apparatus by this invention. (B) It is a side view at the time of the inclination of the conveyance means of the X-ray foreign material detection apparatus by this invention. It is explanatory drawing which shows the inclination structure of a conveying means. It is a perspective view which shows the inclination operation | movement of a conveyance means. It is a perspective view which shows the inclination operation | movement of a conveyance means. It is a perspective view which shows the inclination operation | movement of a conveyance means. (A), (b) It is explanatory drawing which shows the X-ray irradiation state by the conventional X-ray foreign material detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... X-ray foreign material detection apparatus 5 ... Conveyance means 6 ... Conveyor
9 ... Conveyor belt 11 ... Drive source (drive motor)
12 ... Guide conveyor
DESCRIPTION OF SYMBOLS 14 ... Guide belt 17 ... Actuator 18 ... X-ray generator 19 ... X-ray detector W ... Inspection object Y ... Conveyance direction

Claims (4)

A transport means (5) for transporting the inspection object (W) on the transport surface in a predetermined transport direction (Y);
An X-ray generator (18) for irradiating X-rays toward the inspection object conveyed on the conveyance surface;
An X-ray foreign object detection device comprising: an X-ray detector (19) disposed opposite to the X-ray generator across the transport surface and receiving the X-rays transmitted through the inspection object on the X-ray detection surface In (1),
The transport means includes a transport conveyor (6) in which a transport belt (9) forming the transport surface is circulated, and is provided so as to be tiltable so that an angle of the transport surface with respect to the X-ray detection surface can be changed. And a guide belt (14) forming a guide surface orthogonal to the transport surface is circulated at the same speed as the transport belt, and is inclined integrally with the transport conveyor while supporting the side surface of the inspection object. An X-ray foreign matter detection apparatus comprising a guide conveyor (12) for guiding the conveyance of the inspection object. The X-ray foreign object detection device according to claim 1, wherein the transport conveyor (6) and the guide conveyor (12) have a common drive source (11) . The X-ray foreign matter detection device according to claim 1 or 2, further comprising an actuator (17) for inclining the transport means (5) . A sensor for detecting the inspection object (W) carried into the transport means (5);
The X-ray foreign matter detection device according to claim 3, wherein the actuator (17) is operated based on a detection signal from the sensor .

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