JPH0949883A - Foreign matter inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect both foreign matter of metals and non-metals by irradiating the specimens with radiation without directly leaking primary scattering of radiation out of openings for carrying in and out the specimens. SOLUTION: An X-ray shield body 9 having openings 9a and 9b for carrying in and out specimens 2 surrounds X-ray shield bodies 8a to 8c, an upper conveyor 5, an X-ray tube 6, an X-ray sensor 7, etc. In this shield body space, most X-ray of the tube 6 irradiates specimens 2 by way of the slit 11a of the X-ray collimator 11 and transmits through the specimens 2, the belts on a horizontal plane, the slit 8a1 of the shield body 8a and goes in the sensor 7. On the other hand, the primary scattering X-ray 61 (the extended line between the irradiation sport of X-ray on the specimens 2 surface and pulley 10) partly generated during irradiating the specimens 2 irradiates the vicinity of lower end of upper fringe of the openings 9a and 9b to be secondary scattering X-ray and attenuates to 1 millionth of the tube 6 X-ray so that it clears the legal requirement X-ray leak level. By this, both of metal and non-metal foreign matters in the specimens 2 can be detected without direct leakage of radiation.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to, for example, food materials,
The present invention relates to a foreign substance inspection device capable of inspecting foreign substances mixed in foods and the like.

[0002]

2. Description of the Related Art Conventionally, as an example of a foreign matter inspection apparatus for foreign matter mixed in food, as shown in FIGS. 13 (a) and 13 (b),
Belt conveyors 50 and 55 that convey food, and a metal detector 60 that detects a metal in food and that detects a metal by generating an eddy current in the metal by applying a magnetic field. A weight measuring device 70 is provided for detecting the weight of food and determining whether the food is out of stock or in excess.

[0003]

The metal detector 60 used in the foreign matter inspection apparatus having such a structure exhibits good detection ability when metal alone is present as a foreign matter, and therefore has no problem.

However, in the case of the reaction of food with a magnetic field or the packaging with metal foil, there is a limit to the foreign matter detection capability. Further, the metal detector 60 is naturally unable to detect a non-metallic foreign substance. From such a thing,
It has been desired to develop a foreign matter inspection device that can detect foreign matter regardless of whether it is metal or non-metal.

An object of the present invention is to satisfy the above demands, and it is an object of the present invention to provide a foreign substance inspection apparatus capable of detecting foreign substances regardless of whether they are metallic or non-metallic.

[0006]

In order to achieve the above-mentioned object, the invention according to claim 1 irradiates an object to be inspected with radiation from a radiation source while conveying the object to be inspected by a conveying means. A radiation detector detects radiation transmitted through an inspection object, thereby inspecting foreign matter mixed in the inspection object, wherein the radiation source, the radiation detector, and the inspection object are exposed to radiation. Primary scattered radiation generated by irradiating the object to be inspected with radiation emitted from the radiation source is housed in the shielded space and is used for carrying in and out the object to be inspected carried by the carrying means. The foreign matter inspection apparatus has a structure that does not directly come out of the opening.

In order to achieve the above object, the invention according to claim 2 has a horizontal surface portion and an inclined surface portion, and
A pulley which also functions as a radiation shield is provided at a position where the two intersect, an upper conveyor for lifting the inspection object upward by the inclined surface portion, and for inspecting the inspection object on the horizontal surface portion, and an upper portion of the upper conveyor. A radiation source for irradiating the object to be inspected with radiation and a radiation detector for detecting the radiation passing through the object to be inspected, and a lower side of the upper conveyor, which are respectively arranged above and below the horizontal surface of the conveyor. First radiation shielding means, which is disposed on the first radiation guiding means and guides only the radiation transmitted through the inspection object to the radiation detector,
Part of the inclined surface portion of the upper conveyor, the first radiation shielding means, the radiation source, while surrounding the radiation detector, having an opening for carrying in and carrying out the inspection object at a position facing each other, A second radiation shielding means for shielding radiation, a primary scattering point generated when the radiation is irradiated to the inspection object, and a contact point of the pulley of the upper conveyor, which is orthogonal to the conveyance surface of the inspection object. An extension of a straight line connecting the two parts hits near the lower end of the upper edge of the opening, and the inspection object can pass between the inclined surface of the upper conveyor and the opening of the second radiation shielding means. The foreign matter inspection device is characterized by the above.

In order to achieve the above object, the invention according to claim 3 conveys an object to be inspected in a substantially horizontal direction, and a lower conveyor having a shielding means at a lower portion, and a lower conveyor. It is arranged adjacent to the conveyor and has a horizontal plane portion and an inclined surface portion, and has a pulley which also serves as a radiation shield at a position where these both intersect, lifting the inspection object upward by the inclined surface portion, and An upper conveyor for inspecting the object to be inspected in a horizontal plane portion, and a radiation source and an object to be inspected, which are respectively disposed above and below the horizontal plane portion of the upper conveyor to irradiate the object to be inspected with radiation. A radiation detector for detecting radiation passing through the first radiation, and a first radiation detector arranged on the lower side of the upper conveyor for guiding only radiation passing through the inspection object to the radiation detector. A line shielding unit that surrounds the upper conveyor, the first radiation shielding unit, the radiation source, and the radiation detector, and has an opening for loading and unloading the object to be inspected, which shields radiation. And a cylindrical radiation shielding means which is horizontally attached to the opening of the second radiation shielding means, surrounds the lower conveyor, and can convey the object to be inspected by the lower conveyor. A linear extension line connecting the contact point of the pulley of the upper conveyor orthogonal to the conveyance surface of the object to be inspected and the joining position of the cylindrical radiation shielding means and the opening of the second radiation shielding means. The foreign matter inspection apparatus is configured to hit the lower conveyor.

In order to achieve the above object, the invention according to claim 4 is such that a contact point of a pulley of the upper conveyor, the contact point being orthogonal to a carrying surface of the object to be inspected, the cylindrical radiation shielding means, and the second radiation shielding means. At the joining position of the opening of the radiation shielding means, the end of the flexible radiation shielding member extended to the protruding end of the cylindrical radiation shielding means or the adjacent portion of the upper conveyor and the lower conveyor. 4. The foreign matter inspection apparatus according to claim 3, wherein an extension line of a straight line connecting with and hits the lower conveyor.

In order to achieve the above-mentioned object, the invention according to claim 5 is such that a lower conveyor which conveys an object to be inspected in a substantially horizontal direction, and a horizontal plane portion which is arranged adjacent to the lower conveyor. And a sloped surface portion, and a pulley that also functions as a radiation shield at a position where both of them intersect, the inspection object is lifted upward by the sloped surface portion, and the inspection object is inspected on the horizontal surface portion. And a radiation source for irradiating the inspected object with radiation and a radiation source for detecting radiation transmitted through the inspected object. And a first radiation shielding means which is disposed on the lower side of the upper conveyor and guides only the radiation transmitted through the inspection object to the radiation detector, and the upper portion. Shield, the first radiation shielding means, the radiation source, the radiation detector, and a part of the inclined surface of the upper conveyor, and an opening for loading and unloading the object to be inspected. Second
And a linear extension line that connects the primary scattering point generated when the radiation is irradiated to the inspection object and the contact point of the pulley of the upper conveyor that is orthogonal to the conveyance surface of the inspection object. A foreign matter characterized in that the object to be inspected is allowed to pass near the lower end of the upper edge of the opening and between the inclined surface of the upper conveyor and the opening of the second radiation shielding means. It is an inspection device.

In order to achieve the above object, the invention according to claim 6 is the metal detecting means arranged inside or outside the second radiation shielding means for detecting the metal in the object to be inspected, and the metal detecting means. The foreign matter inspection apparatus according to claim 5, comprising at least one of weight measuring means for measuring the weight of the object to be inspected.

In order to achieve the above object, the invention according to claim 7 is directed to a linear conveyor that conveys an object to be inspected in a linear direction, and the linear conveyors are arranged on both sides of the linear conveyor in the conveying direction. Two curved conveyors that change the transport direction of the inspection object in the same plane as the linear conveyor, and are arranged in a direction orthogonal to the transport direction of the inspection object of the linear conveyor, and A radiation source for irradiating the inspection object with radiation and a radiation detector for detecting the radiation passing through the inspection object, and the linear conveyor, the curve conveyor, the radiation source, and the radiation detector are surrounded, and the inspection object is carried in, Radiation shielding means having an opening for carrying out, so that primary scattered radiation generated when the radiation is irradiated to the inspection object is irradiated to the inner wall of the second radiation shielding means. A foreign matter inspection apparatus characterized by constituting the.

In order to achieve the above object, the invention according to claim 8 is the metal detecting means, which is arranged inside or outside the second radiation shielding means and detects the metal in the object to be inspected, and the metal detecting means. 8. The foreign matter inspection apparatus according to claim 7, comprising at least one of weight measuring means for measuring the weight of the object to be inspected.

In order to achieve the above-mentioned object, the invention according to claim 9 is a metal detecting means which is arranged near the curve conveyor in the second radiation shielding means and detects the metal in the object to be inspected. 8. The foreign matter inspection apparatus according to claim 7, comprising at least one of weight measuring means for measuring the weight of the object to be inspected.

In order to achieve the above object, the invention according to claim 10 is characterized in that the radiation source is an X-ray source and the radiation detector is a linear detector having a one-dimensional spread. The foreign matter inspection device described in any one of 2, 3, 5, and 7.

[0016]

According to the invention as set forth in any one of claims 1 to 10, foreign matter in the object to be inspected can be detected regardless of whether it is a metal or a non-metal, and primary scattering is carried out from the loading / unloading port of the object to be inspected. It is possible to obtain a foreign matter inspection device that does not directly leak radiation.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The radiation used here is described by taking X-rays as an example, but the radiation is not limited to this and other radiation may be used.

<First Embodiment> As shown in FIG. 1A, a lower portion is installed on a pedestal 1 at a distance from each other and is conveyed in a substantially horizontal direction for inspecting an object 2 to be inspected. The belt conveyors (hereinafter referred to as lower conveyors) 3 and 4 are arranged between the lower conveyors 3 and 4, and have a horizontal surface portion 5a and inclined surface portions 5b and 5c, and the object 2 to be inspected is inclined surface portions 5b and 5c. With the horizontal plane 5
An upper conveyor 5 for inspecting the inspection object 2 at a.
And the upper and lower planes 5a of the upper conveyer 5 are sandwiched therebetween, and are arranged above and below, respectively.
Radiation source for irradiating X-rays, X-ray tube 6, X-ray collimator 11 for collimating X-rays from X-ray tube 6 and radiation sensor for detecting X-rays transmitted through inspection object 2, for example, one-dimensional line sensor X-ray sensor 7
On the lower side of the upper conveyor 5 and on the horizontal surface portion 5a,
The X-ray sensor 7 is provided so as to correspond to the inclined surface portions 5b and 5c, respectively, and guides only the X-rays that pass through the inspection object 2 to the X-ray sensor 7, and also serves as a member for smoothly sliding and guiding the belt, and partly. A plate-shaped X-ray shield 8a having slits 8a1 for passing X-rays through the plate, and a plate-shaped X-ray shield 8
b, 8c, upper conveyor 5, X-ray shield (constituting first radiation shielding means) 8a-8c, X-ray tube 6, X-ray sensor 7, lower conveyors 3, 4 and portions adjacent to upper conveyor 5 And an X-ray shield (second radiation shielding means) 9 having openings 9a and 9b for loading and unloading the object 2 to be inspected. Primary scattered X-rays 61 generated when the object 2 is irradiated (the X-ray irradiation point on the surface of the object 2 to be inspected and the horizontal plane portion 5 of the upper conveyor 5).
a is an opening portion of the X-ray shield 9 which is an extension line of a straight line connecting a contact point of the pulley 10 also serving as an X-ray shield, which intersects with the conveyance surface of the inspection object 2 and which intersects at a position where a and the inclined surface portions 5b and 5c intersect. 9
It is configured to hit the lower end of the upper edge of a, 9b.

The inclination angle of the inclined surface portion 5b of the upper conveyor 5 is set so that the inspection object 2 does not drop, and is specifically about 10 degrees. Lower conveyor 3,4
Is equipped with a plurality of rollers that are all driven to rotate by a motor or the like (not shown) and a belt that slides around the outer circumference of each roller. It has a belt that slides on the outer periphery, and is configured so that the inspected object 2 can be lifted up to the horizontal surface portion 5a by the inclined surface portion 5b and can be conveyed to the lower conveyor 4 through the inclined surface portion 5c.

FIG. 1B shows the opening 9a of the X-ray shield 9, the X-ray focal point of the X-ray tube 6, the upper surface of the upper conveyor 5, and the lower conveyor 3 when viewed from the side direction of FIG. It is a figure which shows the relationship of the upper surface of.

In such a structure, the X-ray tube 6
Most of the X-rays generated from the X-ray collimator 11 irradiate the inspection object 2 through the slit 11a so that the inspection object 2 and the belt of the horizontal plane 5a of the upper conveyor 5 and the X-ray shield 8a. The light passes through the slit 8a1 and enters the X-ray sensor 7.

On the other hand, the rest of the X-rays generated from the X-ray tube 6 is applied to the object 2 to be inspected, so that the primary scattered X-rays 6 are emitted.
1 (dashed line in FIG. 1 (a)) is generated, but this single scattering attenuates to about 0.1% of the X-ray incident from the X-ray tube 6.

Then, the primary scattered X-rays 61 are converted into X-ray shields 9.
Since it is irradiated near the lower end of the upper edge of the opening 9a of
The primary scattered X-rays 61 become secondary scattered X-rays. As a result, X
The X-rays incident from the ray tube 6 are attenuated to about one millionth. As a result, even if the X-ray shield 9 has openings 9a and 9b,
An X-ray system can be configured that clears legal X-ray leakage.

Further, since the X-ray sensor 7 is composed of a one-dimensional line sensor, the X-rays are fan beams (fan-shaped beams), so that the X-rays are less scattered and are more easily shielded.

Further, even when the object to be inspected 2 is wrapped in a metal foil, it is a method of irradiating X-rays,
Foreign matter can be detected.

<Second Embodiment> As shown in FIG.
X-ray shielding tunnel members 12a, 12 are newly added to the example of FIG.
b, lower conveyors 3 and 4 having X-ray shielding members 13 and 14, respectively, are added as follows. That is, the X-ray shielding tunnel member 12a is horizontally attached to the opening 9a of the X-ray shielding body 9 (second radiation shielding means), surrounds the lower conveyor 3 having the X-ray shielding member 13, and shields the X-rays. The tunnel member 12b is horizontally attached to the opening 9b of the line shield 9 (second radiation shielding means) so as to surround the lower conveyor 4 having the X-ray shielding member 14, and further to the pulley 10 of the upper conveyor 5. A contact point orthogonal to the conveyance surface of the inspection object 2 and the tunnel member 12a
And a linear extension line (primary scattered X-ray) 61 connecting the joining position of the opening 9a of the X-ray shield 9 hits the lower conveyor 3, and the lower conveyor 4 is similarly configured.

Also in FIG. 2 having such a configuration, as shown in FIG.
The same action and effect can be obtained.

<Third Embodiment> As shown in FIG.
In the example shown in FIG. 2, the tunnel members 12a and 12b are attached to the openings 9a and 9b of the X-ray shield 9 in the following manners. That is, the tip portion 12a1 of the tunnel member 12a is inserted into the opening 9a of the X-ray shield 9.
Is inserted into the inside of the X-ray shield 9 so as to approach the inclined surface portion 5b of the upper conveyor 5, and the tip end portion 12b of the tunnel member 12b is attached to the opening 9b of the X-ray shield 9.
1 is attached in a state of being inserted into the inside of the X-ray shield 9 so that the reference numeral 1 approaches the inclined surface portion 5c of the upper conveyor 5.

Also in FIG. 3 configured as described above, FIG.
The same action and effect can be obtained.

<Fourth Embodiment> As shown in FIG.
The opening 9a of the X-ray shield 9 and the tunnel member 1 of the example of FIG.
A flexible lead-containing shield 15a such as a rubber blind is provided on the upper edge side of the opening 9a at the joint portion of 2a and the conveyor 3
It is attached so that it hangs down (closes) to the side, and at the joint of the opening 9b of the X-ray shield 9 and the tunnel member 12b, on the upper edge side of the opening 9b, a flexible lead-containing material such as a rubber blind is inserted. Only the point where the shield 15b is attached so as to hang down (close to) the conveyor 3 side is shown in FIG.
Is different from.

In this case, X-rays are emitted from the X-ray tube 6 to be inspected 2
Since the primary scattered X-rays 61 generated when irradiating the X-ray collide with the lead-containing shield 15a, the X-ray shield tunnel member 12
It is possible to prevent the primary scattered X-rays 61 from being directly emitted to the outside from the opening end portion of a. In this case, the same goes for the lead-containing shield 15b.

<Fifth Embodiment> As shown in FIG. 5A, the arrangement positions of the X-ray tube 6 and the X-ray sensor 7 in the example of FIG. 1 are reversed, that is, the X-ray tube 6 and the X-ray. The point where the collimator 11 is arranged on the gantry 1 side and the X-ray sensor 7 is arranged between the X-ray shield 9 and the inspection object 2, and FIG. 5 (b) [as shown in FIG. 5 (a). 1 is different from FIG. 1 only in that the X-ray tube 6 is housed in an X-ray shield box 16 to prevent leakage of X-rays to the outside.

With the configuration shown in FIG. 5, when the X-ray generated from the X-ray tube 6 is applied to the object 2 to be inspected, X-ray is emitted.
The rays are scattered, but in this case, the strongest scattering occurs on the horizontal plane portion 5a of the upper conveyor 5 and becomes primary scattered X-rays 61, and the primary scattered X-rays 61 are on the side surface of the X-ray shield 9 (the side having the opening 9a). Hit. Therefore, it is possible to prevent the primary scattered X-rays 61 from being directly emitted to the outside.

<Sixth Embodiment> FIG. 6 is a block diagram showing a schematic structure of a foreign matter inspection apparatus in which the metal detector 22 and the weight measuring device 24 using the conventional magnetic field of FIG. 13 are combined with the above-described example. And the metal detector 22 and the weight measuring device 24
The detection signals respectively detected by and the X-ray transmission detection signal of the object 2 to be detected from the X-ray detector 7 are both input into the central processing unit (CPU) 21, and based on these signals, Since it is determined whether or not there is a foreign substance in the inspection object 2 and the weight of the inspection object 2 is measured, the weight excess of the inspection object 2 is determined.

The determination of foreign matter in the central processing unit 21 is performed by automatically image-processing the X-ray transmission detection signal of the object 2 to be detected from the X-ray detector 7, and the presence of foreign matter. Then, it is determined that the foreign matter is a metal or a non-metal according to the detection signal of the metal detector 22, and the foreign matter detection signal is output from the central processing unit 21.

When this foreign matter detection signal is output, an operation command is given to a bouncing device (not shown) arranged adjacent to the lower conveyor 4, and the object 2 to be inspected containing foreign matter is detected. It is automatically removed from the conveyor conveyor line.

In this operation, the detection signal from the weight measuring device 24 indicating that the weight is exceeded is detected by the central processing unit 21.
Similarly, an operation command is given to the popping-out device, and the object 2 to be inspected having an excessive weight is automatically removed from the convey line of the conveyor.

The X-ray inspection control unit 20 is provided between the X-ray tube 6 and the central processing unit 21 and supplies a control signal for X-ray inspection to the central processing unit 21. Further, the metal detector control unit 23 is provided between the metal detector 22 and the central processing unit 21, and gives a control signal for operating the metal detector 22 to the central processing unit 21.

FIG. 7 is a cross-sectional view showing the specific structure of FIG. 6, in which tunnel members 25 and 26 are provided on the side of the openings 9a and 9b of the X-ray shield 9, and metal detection is performed inside them. The container 22 and the weight measuring device 24 are housed so that the metallic foreign matter in the inspection object 2 conveyed to the lower conveyors 3 and 4 and the excess weight of the inspection object 2 can be detected.

<Seventh Embodiment> As shown in FIG.
Tunnel members 251, 261 are provided on the sides of the openings 9a, 9b of the X-ray shield 9, respectively, and inside the X-ray shield 9, the inclined surfaces 5b, 5c of the upper conveyor 5 are respectively provided with the metal detector 22. A weight measuring device 24 is provided so that the metallic foreign matter in the inspection object 2 conveyed to the lower conveyors 3 and 4 and the excess weight of the inspection object 2 can be detected. In this case, since the weight measuring device 24 uses a conveyor to measure the weight, the above-described upper conveyor 5 has a structure in which the horizontal surface portion 8a and the inclined surface portion 8c are independent of each other. The slope is provided on the conveyor 28 itself, which is a substitute for the inclined surface portion 8c. A shielding member 27 is vertically arranged between the conveyor 28 and the horizontal surface portion 8a of the upper conveyor 5.

In the case of this example, there is an advantage that the whole can be made smaller than the example of FIG.

<Eighth Embodiment> As shown in FIG.
Straight conveyor 30, two curved conveyors 31, 32,
Two tunnel members 33, 34 made of two shielding materials,
It consists of an X-ray tube (not shown) and an X-ray detector (not shown), which are constructed by combining them in a plane as follows. That is, a straight line conveyor 30 that conveys an object to be inspected (not shown) in a straight line direction, and a curve conveyor that is arranged on both sides of the straight line conveyor 30 in the same plane as the straight line conveyor 30 along the straight line conveyor 30 conveyance direction. X-ray tubes 31 and 32, which are arranged in a direction orthogonal to the conveying direction of the inspected object on the linear conveyor 30, and which irradiate the inspected object with radiation, and X-rays that pass through the inspected object. X-ray detector for detecting
An X-ray shielding member 38 that surrounds the curve conveyors 31 and 32, the X-ray tube, and the X-ray detector, and has an opening for loading and unloading the object to be inspected, and is connected to the X-ray shielding member 38, respectively. Tunnel members 33 and 34 made of an X-ray shielding material surrounding the curve conveyors 31 and 32, and the primary scattered radiation 36 and 37 generated when the X-ray beam 35 is applied to the inspection object is the tunnel members 33 and 34. The line-of-sight angle is set so as to irradiate the inner wall of the X beam, that is, from the generation point of the X beam 35.

As described above, the linear conveyor 30 is arranged between the curved conveyors 31 and 32, and the tunnel members 33 and 34 and the shielding member 38 are provided so as to surround them, and the X portion is provided at the portion where the course of the conveying process changes. Since the X-ray detector is provided, the primary scattering does not directly appear outside, and the X-ray foreign matter can be detected regardless of whether it is a metal or a non-metal.

<Ninth Embodiment> As shown in FIG. 10, a metal detector 39 with a tunnel and a load with a tunnel are newly provided in a part of the tunnel members 33 and 34 in the example of FIG. The detector 40 is provided. The X-ray inspector 41 is composed of the above-mentioned X-ray tube and X-ray detector.

<Tenth Embodiment> As shown in FIG. 11, a metal detector 39 with a tunnel and a load detector with a tunnel which respectively utilize magnetic fields at the positions of the curve conveyors 31 and 32 in the example of FIG. 40 is provided. In addition,
The X-ray inspector 41 is composed of the aforementioned X-ray tube and X-ray detector.

<Eleventh Embodiment> As shown in FIG. 12, horizontal conveyors 42 and 43 are arranged with a step,
An inclined conveyor 44 having a shield 46 is disposed between the horizontal conveyors 42, 43, an X-ray tube 46 is disposed above the central portion of the inclined conveyor 44, and below the central portion of the inclined conveyor 44. X-ray detector 4 housed in an X-ray shielding box 48
7 is provided, and the X-ray tube 4 is provided above the inclined conveyor 44.
6. A tunnel having an X-ray shielding member 49 arranged so as to surround 6 and further configured so as to surround horizontal conveyors 42 and 43, and having a metal detector 39 and a load detector 40 that utilize magnetic fields inside, respectively. A member is provided.

With this structure, since the opening for loading and unloading the object to be inspected is at the top and bottom, the primary scattered X-ray is not exposed to the outside from this opening.

<Modification> As the above-mentioned embodiment, the combination of the X-ray inspection device 41, the metal detector 39, and the load measuring device 40 has been described as an example. Even if the detector 39 is combined, or the X-ray inspector 41 and the load measuring device 40 are combined, the same effect as the above-described example can be obtained.

Further, the arrangement positions of the metal detector 39 and the load measuring device 40 may be exchanged in reverse to the above-mentioned example.

Further, as the X-ray shielding structure, the level difference between the upper and lower sides of the conveyor and the curve are shown, but a structure in which these are combined may be used.

[0052]

As described above, according to the present invention, foreign matter in an object to be inspected can be detected regardless of whether it is metal or non-metal, and primary scattered radiation does not directly leak from the loading / unloading port of the object to be inspected. A device can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a foreign matter inspection device of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the foreign matter inspection device of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the foreign matter inspection device of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the foreign matter inspection device of the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the foreign matter inspection device of the present invention.

FIG. 6 is a block diagram showing a schematic configuration of a sixth embodiment of a foreign matter inspection device of the present invention.

FIG. 7 is a sectional view showing a sixth embodiment of the foreign matter inspection apparatus of the present invention.

FIG. 8 is a cross-sectional view showing a seventh embodiment of a foreign matter inspection device of the present invention.

FIG. 9 is a sectional view showing an eighth embodiment of the foreign matter inspection apparatus of the present invention.

FIG. 10 is a sectional view showing a ninth embodiment of the foreign matter inspection apparatus of the present invention.

FIG. 11 is a sectional view showing a tenth embodiment of a foreign matter inspection device of the present invention.

FIG. 12 is a sectional view showing an eleventh embodiment of the foreign matter inspection apparatus of the present invention.

FIG. 13 is a sectional view showing an example of a conventional foreign matter inspection apparatus.

[Explanation of symbols]

1 ... Stand, 2 ... Inspected object, 3, 4 ... Lower conveyor, 5 ...
Upper conveyor, 5a ... Horizontal plane part, 5b, 5c ... Sloping surface part, 6 ... X-ray tube, 61 ... Primary scattered X-ray, 7 ... X-ray sensor, 8a-8c ... X-ray shield, 9 ... X-ray shield, 9a,
9b ... Aperture, 10 ... Pulley, 11 ... X-ray collimator,
12a, 12b ... Tunnel member, 13, 14 ... X-ray shielding member, 22 ... Metal detector, 24 ... Weight measuring device, 30 ... Linear conveyor, 31, 32 ... Curve conveyor, 33, 34
… Tunnel member, 35… X-ray beam, 36… Primary scattering X
line.

Claims (10)

[Claims] 1. An object to be inspected is being irradiated with radiation from a radiation source while the object to be inspected is being conveyed by a conveying means, and radiation transmitted from the object to be inspected is detected by a radiation detector, whereby the object to be inspected is detected. A method for inspecting foreign matter mixed in, wherein the radiation source, the radiation detector, and the object to be inspected are housed in a radiation shield space, and the radiation emitted from the radiation source is to the object to be inspected. A foreign matter inspection apparatus having a structure such that the primary scattered radiation generated by being irradiated does not directly exit from an opening portion for carrying in and out the object to be inspected carried by the carrying means. . 2. A horizontal plane portion and an inclined surface portion are provided, and a pulley which also functions as a radiation shield is provided at a position where the horizontal surface portion and the inclined surface portion intersect with each other, and an object to be inspected is lifted up by the inclined surface portion, and at the horizontal surface portion, An upper conveyor for inspecting an object to be inspected, and a radiation source for irradiating the object to be inspected with radiation and a radiation passing through the object to be inspected, which are respectively arranged above and below the horizontal plane part of the upper conveyor. A radiation detector for detecting the radiation, a first radiation shielding means disposed on the lower side of the upper conveyor, which guides only radiation passing through the inspected object to the radiation detector, and an inclined surface portion of the upper conveyor. Part of the first radiation shielding means, the radiation source, and the radiation detector are surrounded, and openings for loading and unloading the object to be inspected are provided at positions facing each other. A second radiation shielding means for shielding radiation, a primary scattering point generated when the radiation is irradiated to the inspection object, and a contact point of the pulley of the upper conveyor, which is orthogonal to the conveyance surface of the inspection object. An extension line of a straight line connecting with and hits the lower edge of the upper edge of the opening near the lower edge of the upper conveyor, and allows the object to be inspected to pass between the inclined surface of the upper conveyor and the opening of the second radiation shielding means. A foreign matter inspection device characterized by being configured. 3. A lower conveyor which conveys an object to be inspected in a substantially horizontal direction and has a shielding means at a lower portion, and a lower conveyor which is disposed adjacent to the lower conveyor and has a horizontal surface portion and an inclined surface portion. And has a pulley that also serves as a radiation shield at the position where the two intersect, an upper conveyor for inspecting the object to be inspected upward by the inclined surface portion and inspecting the object to be inspected in the horizontal plane portion. A radiation source for irradiating the object to be inspected with radiation and a radiation detector for detecting radiation passing through the object to be inspected; A first radiation shielding unit which is disposed on the lower side of the conveyor and guides only the radiation that passes through the inspection object to the radiation detector; the upper conveyor; and the first radiation. Second radiation shielding means for surrounding the line shielding means, the radiation source, and the radiation detector, and having an opening portion for carrying in and out the object to be inspected, and shielding the radiation, and the second radiation shielding means. And a cylindrical radiation shielding means capable of horizontally mounting the lower conveyor around the lower conveyor and transporting the inspected object by the lower conveyor, and the inspected object of the pulley of the upper conveyor. And a straight line extending from the contact point orthogonal to the conveyance surface of the second radiation shielding means and the joining position of the openings of the cylindrical radiation shielding means and the second radiation shielding means collide with the lower conveyor. Foreign matter inspection device. 4. A contact position of a pulley of the upper conveyor, which is orthogonal to a conveyance surface of the object to be inspected, a joint position of the cylindrical radiation shielding means and an opening of the second radiation shielding means, and A straight extension line connecting the protruding end of the cylindrical radiation shielding means or the end of the flexible radiation shielding member extended to the adjacent portion of the upper conveyor and the lower conveyor may collide with the lower conveyor. The foreign matter inspection apparatus according to claim 3, wherein the foreign matter inspection apparatus is configured as described above. 5. A lower conveyor that conveys an object to be inspected in a substantially horizontal direction, and a lower conveyor that is disposed adjacent to the lower conveyor and has a horizontal surface portion and an inclined surface portion, and at a position where these both intersect. It has a pulley that also serves as a radiation shield, lifts the object to be inspected upward by the inclined surface portion, and an upper conveyor for inspecting the object to be inspected on the horizontal surface portion, and sandwiches the horizontal surface portion of the upper conveyor. In each of the lower and upper portions thereof, a radiation source for irradiating the object to be inspected with radiation and a radiation detector for detecting the radiation passing through the object to be inspected, and disposed on the lower side of the upper conveyor, First radiation shielding means for guiding only radiation passing through the inspection object to the radiation detector, the upper conveyor, the first radiation shielding means, the radiation A second radiation shielding means for shielding radiation, the radiation detector and a part of an inclined surface portion of the upper conveyor being surrounded, and having an opening portion for loading and unloading the object to be inspected, An extension line of a straight line connecting a primary scattering point generated when the inspection object is irradiated with radiation and a contact point of the pulley of the upper conveyor orthogonal to the conveyance surface of the inspection object is near the lower end of the upper edge of the opening. The foreign matter inspection apparatus, wherein the object to be inspected is capable of passing through an inclined surface portion of the upper conveyor and an opening portion of the second radiation shielding means. 6. At least one of a metal detection unit, which is disposed inside or outside the second radiation shielding unit and detects a metal in the inspection object, and a weight measurement unit which measures the weight of the inspection object. The foreign matter inspection apparatus according to claim 5, wherein the foreign matter inspection apparatus comprises: 7. A linear conveyor that conveys an inspected object in a linear direction, and a linear conveyor that is disposed on both sides of the linear conveyor along the conveying direction and that is in the same plane as the linear conveyor. Two curve conveyors for changing directions, a radiation source arranged in a direction orthogonal to a conveyance direction of the inspection object of the linear conveyor, and a radiation source for irradiating the inspection object with radiation, and the inspection object A radiation detector for detecting the radiation passing through, a linear conveyor, a curved conveyor, a radiation source, surrounding the radiation detector, carrying in and out the object to be inspected, comprising a radiation shielding means having an opening. The foreign matter inspection apparatus is configured such that primary scattered radiation produced when the radiation is applied to the inspection object is applied to the inner wall of the second radiation shielding means. 8. At least one of a metal detecting means arranged inside or outside the second radiation shielding means for detecting a metal in the inspection object and a weight measuring means for measuring the weight of the inspection object. The foreign matter inspection apparatus according to claim 7, characterized by comprising: 9. At least metal detection means for detecting the metal in the object to be inspected and weight measuring means for measuring the weight of the object to be inspected, which is arranged near the curved conveyor in the second radiation shielding means. The foreign matter inspection apparatus according to claim 7, wherein the foreign matter inspection apparatus comprises one. 10. The radiation source is an X-ray source, and the radiation detector is a linear detector having a one-dimensional spread. Foreign matter inspection device.