JP2003083913A - X-ray inspecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray inspecting apparatus capable of reliably suppressing X-ray leakage from a side of a transfer mechanism. SOLUTION: The X-ray inspecting apparatus 1 is provided with a shield box 2, an X-ray irradiating part 3, a conveyer 5, an X-ray shield curtain 6, and an X-ray line sensor 14. The conveyer 5 is arranged below the X-ray irradiating part 3 to transfer an article to be inspected A. The shield box 2 is provided with an opening part 11 through which the article to be inspected A is transferred in and out. The X-ray shield curtain 6 is arranged in the vicinity of the opening part 11 and above the conveyer 5 to prevent X-ray leakage from an upper part of the opening part 11 to the outside of the shield box 2. The X-ray inspecting apparatus 1 is further provided with side leakage preventing walls 7. The side leakage preventing walls 7 are arranged inside the shield box 2 and on both sides of the conveyer 5 to prevent X-ray leakage from side parts of the opening part 11 to the outside of the shield box 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray inspection apparatus, and more particularly to an X-ray inspection apparatus which prevents leakage of X-rays.

[0002]

2. Description of the Related Art In a production line for products such as foods, an X-ray inspection apparatus may be used in order to prevent the shipment of such products when foreign matters are mixed into the products or the products are cracked or chipped. . This X-ray inspection apparatus irradiates each inspected article that is continuously conveyed with X-rays, detects the transmission state of the X-rays with an X-ray detection unit such as an X-ray line sensor, and It is determined whether or not foreign matter is mixed in, whether the article is cracked or chipped, or the number of units in the article is insufficient. In addition, the number of units in an article is counted by an X-ray inspection apparatus.

The X-ray inspection apparatus has openings (carrying-in port, carrying-out port) on both sides, and the articles to be inspected are carried into and out of the X-ray inspection apparatus through a transport mechanism such as a belt conveyor through the openings. Then, the X-ray inspection is performed.

[0004]

In the X-ray inspection apparatus, the X
There is a problem that the wire leaks outside the device. When the X-ray irradiation unit irradiates the X-ray detection unit, the X-rays pass through the article to be inspected, the transport mechanism, the surface of the X-ray detection unit, and the like. At this time, part of the X-rays is scattered on the surface of the object. The scattered X-rays may leak out of the X-ray inspection apparatus through the openings or the like. Therefore, the X-ray inspection apparatus needs to take measures against X-ray leakage.

In order to reduce the leakage of X-rays from the opening, an X-ray shielding shutter or the like is provided in the opening and the shutter is closed, as shown in Japanese Patent Laid-Open No. 178872/1996. X-ray leakage is suppressed only by performing X-ray irradiation only occasionally.

However, for shielding with a shutter or the like,
Since it is necessary to open and close the shutter every time the X-ray inspection is performed, opening and closing time is required. Further, since the shutter has to be closed every time the inspected article is inspected by X-ray, the timing of closing the shutter is limited or it is necessary to lengthen the transportation interval of the inspected article.
For these reasons, it is difficult for an X-ray inspection apparatus using an X-ray blocking shutter to perform high-speed processing.

Therefore, X is usually used as an X-ray shielding member.
It is performed that the ray shielding curtain is hung from above the opening of the X-ray inspection apparatus. At this time, the gap between the X-ray shielding curtain and the transport mechanism is reduced as much as possible,
In addition, the length of the X-ray shielding curtain is set so as to be in contact with the transport mechanism so that the article to be inspected can easily move into the X-ray inspection apparatus. Thereby, the article to be inspected can be pushed into the X-ray inspection apparatus by pushing the X-ray shielding curtain away by the transport mechanism.

On the other hand, when the inspected article is food or the like,
In order to maintain hygiene, the transport mechanism may be detachable to facilitate cleaning of the transport mechanism. However, in the case of such a configuration, in order to facilitate the attachment / detachment work, it is necessary to provide a wider gap between the transport mechanism and the housing as compared with the transport mechanism that cannot be attached / detached. For this reason, a gap is created between the side of the transport mechanism and the inside of the X-ray inspection apparatus, and this gap may be connected to the opening to leak X-rays to the outside.

The object of the present invention is to provide X from the side of the transport mechanism.
An object of the present invention is to provide an X-ray inspection apparatus that can more surely suppress the leakage of rays.

[0010]

An X-ray inspection apparatus according to claim 1 is an X-ray irradiation unit, a transport mechanism, an X-ray detection unit, a housing,
And an X-ray inspection apparatus including an upper leakage prevention member. X
The radiation irradiator is a member that radiates X-rays. The transport mechanism is X
It is a mechanism that is arranged below the line irradiation unit and conveys an article to be inspected. The X-ray detection unit is arranged below the X-ray irradiation unit and the transport mechanism, and detects X-rays from the X-ray irradiation unit. The housing covers the X-ray irradiation unit, the X-ray detection unit, and the transport mechanism,
An opening is provided for loading and unloading articles. The upper leakage prevention member is a member arranged near the opening and above the transport mechanism to prevent X-ray leakage from the upper portion of the opening to the outside of the housing. Here, the X-ray inspection apparatus further includes a side leakage prevention member. The side leakage prevention member is arranged inside the housing and on both sides of the transport mechanism, and prevents X-ray leakage from the side of the opening to the outside of the housing.

In the X-ray inspection apparatus, the article is carried by the carrying mechanism, the X-ray emitted from the X-ray irradiator is transmitted through the article, and the intensity of the transmitted X-ray is detected by the X-ray detector.
Thereby, the inside of the article can be inspected.

Here, in order to suppress leakage of X-rays from the opening, a side leakage prevention member is provided in the X-ray inspection apparatus in addition to the upper leakage prevention member. The side leakage prevention member suppresses X-ray leakage from the gap between the opening and the transport mechanism. By combining these two types of leakage prevention members, it becomes possible to more reliably suppress the leakage of X-rays from the opening.

Examples of the side leakage preventing member include a flexible member such as a lead-containing rubber sheet and a hard member such as a stainless plate. An X-ray inspection apparatus according to a second aspect is the X-ray inspection apparatus according to the first aspect, wherein the side leakage prevention member is arranged near the opening.

Here, since the side leakage preventing member is arranged near the opening, the leakage can be effectively suppressed. An X-ray inspection apparatus according to a third aspect is the X-ray inspection apparatus according to the first aspect, wherein the side leakage prevention member is arranged near the X-ray detection unit.

The X-rays from the X-ray irradiator are often scattered and reflected on the surface of the X-ray detector. Here, since the side leakage prevention member is arranged in the vicinity of the X-ray detection unit, it is possible to effectively suppress X-ray leakage from the opening caused by scattered reflection on the surface of the X-ray detection unit.

An X-ray inspection apparatus according to a fourth aspect is the X-ray inspection apparatus according to the second or third aspect, wherein the transport mechanism is removable and the side leakage prevention member is a side portion of the transport mechanism. Be attached to.

The X-ray inspection apparatus in which the transport mechanism is detachable has a wider gap between the transport mechanism and the housing than the X-ray inspection apparatus having the transport mechanism which cannot be detached in order to facilitate the attachment / detachment work. It is necessary to provide. Therefore, it is necessary for the X-ray inspection apparatus including the detachable transport mechanism to be careful of X-ray leakage from the side of the opening.

Here, since the side leakage prevention member is mounted on the side portion of the transport mechanism, no gap is created between the side leakage prevention member and the transport mechanism, and X-ray leakage can be suppressed more reliably. it can.

An X-ray inspection apparatus according to a fifth aspect is the X-ray inspection apparatus according to the second or third aspect, in which an opening / closing door to which a transport mechanism can be attached / detached is attached to the housing. The side leakage prevention member is attached to the opening / closing door.

Here, since the side leakage preventing member is provided on the opening / closing door, the side leakage preventing member does not easily get in the way when the opening / closing door is opened and the inside of the housing is maintained.
That is, maintenance such as attachment / detachment of the transport mechanism and cleaning of the inside of the housing becomes easy.

An X-ray inspection apparatus according to a sixth aspect of the present invention is the X-ray inspection apparatus according to any one of the first to fifth aspects, wherein a plurality of side leakage prevention members are arranged along the conveyance direction of the conveyance mechanism. To be done.

Here, since a plurality of side leakage prevention members are provided along the conveying direction, the X-rays are shielded by the respective side leakage prevention members. Therefore, leakage of X-rays can be further suppressed.

[0023]

FIG. 1 is an external perspective view of an X-ray inspection apparatus 1 according to the present invention. The X-ray inspection apparatus 1 is an apparatus that conveys an article to be inspected such as food by a conveying mechanism and determines a defect inside the article to be inspected.

<Structure> The X-ray inspection apparatus 1 is shown in FIGS.
Also, as shown in FIG. 4, the shield box 2, the X-ray irradiator 3, the X-ray detector 4, the conveyor 5, the X-ray shielding curtain 6, the side leakage prevention wall 7, the LCD monitor 8, and the controller 9 are shown.
Is equipped with.

The shield box 2 is a housing part for housing the equipment of the X-ray inspection apparatus 1 therein, and shields the X-ray generated inside so as not to leak to the outside. The shield box 2 has openings 11 on both sides,
The article to be inspected is carried in and out of the X-ray inspection apparatus 1 through the opening 11. A synchronization sensor 12 is installed on the side of the opening 11, and the synchronization sensor 12 detects that the article to be inspected is X.
The timing of loading into the line inspection device 1 is detected.
A door 13 for accessing the inside is provided on the front surface of the shield box 2. By opening the door 13 to access the inside, it is possible to clean the inside of the shield box 2 and attach / detach the conveyor 5 described later.

The X-ray irradiator 3 is a device for generating X-rays and irradiating the article, and is provided above the inside of the shield box 2. X-rays from the X-ray irradiator 3 are shown in FIG.
It is irradiated downward as shown in.

The X-ray detector 4 is a device for detecting X-rays from the X-ray irradiator 3, and is provided below the inside of the shield box 2 to which the X-rays from the X-ray irradiator 3 are irradiated. ing. The X-ray detection unit 4 has an X-ray line sensor 1 inside.
4, the X-ray line sensor 14 measures the intensity of X-rays transmitted through the inspected article. Also, X
As shown in FIG. 2, scattered X-rays are formed on the side of the line detection unit 4.
A lower shield member 15 is installed to prevent leakage of the wire.

The conveyor 5 is a carrying mechanism for carrying articles. The conveyor 5 is below the X-ray irradiator 3
It is detachably arranged above the line detection unit 4. Also,
The conveyor 5 is exposed to the outside through the opening 11, and allows an article to be carried into the shield box 2 from an upstream external conveyor (not shown). Take it out on the conveyor. X
As shown in FIG. 2, a conveyor shield member 16 for preventing leakage of X-rays scattered on the surface of the X-ray detection unit 4 is provided below the conveyor 5 near the X-ray detection unit 4.
The conveyor 5 is driven by the rotation of the end roller 17 at the end of the conveyor 5 exposed from the opening 11. The end rollers 17 are, as shown in FIG.
Supported by the conveyor motor 19 and is driven to rotate by the conveyor motor 19. At this time, the speed of the conveyor 5 is monitored by the encoder 20 provided in the conveyor motor 19 and transmitted to the control unit 9 described later.

The X-ray shielding curtain 6 is a curtain made of lead-containing rubber which is hung from above the inside of the shield box 2 so as to contact the conveyor 5. In the present embodiment, the X-ray shielding curtain 6 includes the vicinity of the opening as shown in FIG.
As shown in FIG. 6, it is provided at six places along the conveying direction of the conveyor 5. Since the X-ray shielding curtain 6 contains lead, it absorbs X-rays and prevents leakage of X-rays from the opening 11.

The side leakage prevention wall 7 is a stainless steel plate member provided vertically on the inside of the door 13 and the inside of the back surface of the shield box 2. As shown in FIG. 2, the side leakage prevention walls 7 are provided in the door 13 and four on the back surface of the shield box 2, that is, eight in total. As shown in FIG. 3, the side leakage prevention wall 7 provided on the back surface of the shield box 2 has its end portion extremely close to the conveyor 5. Further, the side leakage prevention wall 7 provided on the door 13 comes extremely close to the conveyor 5 by closing the door 13 (see FIG. 3). Since the side leakage prevention wall 7 is provided on the door, it is unlikely to get in the way when the conveyor 5 is attached or detached.

The LCD monitor 8 is provided above the front surface of the shield box 2 to check the state of the X-ray inspection apparatus 1.
It is a display unit on which an X-ray image of the inspected article, a judgment result, and the like are shown. Further, the LCD monitor 8 has a touch panel function and also performs a display prompting the input of settings and the like.

The control unit 9 is a member for recognizing a defect determination and controlling the X-ray inspection apparatus 1. Control unit 9
As shown in FIG. 4, the CPU 31 is equipped with a CPU 31 and a storage unit such as a ROM 32, a RAM 33, and an HDD 34.

<Operation> The X-ray inspecting apparatus 1 conveys the article A to be inspected by the conveyor 5, and the X-ray line sensor detects the intensity of the X-ray irradiated from the X-ray irradiator 3 and transmitted through the article A to be inspected. Measure at 14. The conveyor 5 is operated by a conveyor motor 19 controlled by the controller 9. The control unit 9 creates an X-ray image of the inspected article A on the basis of the measurement signal of the X-ray line sensor 14 which is acquired while the article A to be inspected A is being conveyed by the conveyor 5. The inside of the inspected article A is inspected by this X-ray image.

<Characteristics> X-rays from the X-ray irradiator 3 are radiated in a fan shape toward the X-ray line sensor 14 below. At this time, by the time the X-rays reach the X-ray line sensor 14 from the X-ray irradiator 3, the surface of the article A to be inspected, the belts on the upper and lower surfaces of the conveyor 5, the surface of the X-ray detection unit 4, and the X-rays. When the X-rays are transmitted on the surface of the line sensor 14, primary scattered X-rays are generated. Due to the generation of scattered X-rays, a part thereof may leak from the opening 11. In order to prevent this scattered X-ray from leaking from the opening 11,
The X-ray inspection apparatus 1 according to the present embodiment includes a side leakage prevention wall 7, a lower shielding member 15, and a conveyor shielding member 16 in addition to the X-ray shielding curtain 6 that is normally used.

First, the X-ray shielding curtain 6 is installed to prevent scattered X-rays from leaking from the upper part of the opening 11. Further, since the lower shield member 15 and the conveyor shield member 16 are provided, the scattered X-rays are prevented from leaking from the lower portion of the opening 11.

X-ray shielding curtain 6, lower shielding member 15,
By installing the conveyor shielding member 16, the radiation dose in the opening 11 can be suppressed to 1 microsievert per hour.

Further, the side leakage prevention wall 7 is provided so as to be extremely close to the conveyor 5, as shown in FIG. As a result, it is possible to make the gap seen on the side of the conveyor 5 as narrow as possible when the X-ray inspection apparatus 1 is viewed from the opening 11. Therefore, the scattered X-rays are suppressed from leaking from the side portion of the opening 11.

By providing all of these X-ray leakage prevention members, the radiation dose in the opening 11 is further suppressed to 0.5 microsievert per hour. Therefore, leakage of scattered X-rays from the opening 11 is sufficiently suppressed.

<Other Examples> (a) In the above embodiment, the stainless steel plate is used as the side leakage prevention wall 7, but a lead-containing rubber sheet or the like may be used instead.

(B) In the above embodiment, the side leakage prevention wall 7 is provided on the door 13, but the side leakage prevention wall 7 may be attached to both sides of the conveyor 5. In this case, since the gap seen on the side of the conveyor 5 when the X-ray inspection apparatus 1 is viewed from the opening 11 can be almost completely eliminated, scattered X-rays leak from the side of the opening 11. Can be further suppressed.

[0041]

In the X-ray inspection apparatus according to the present invention, the side leakage prevention member is provided in the X-ray inspection apparatus in addition to the upper leakage prevention member in order to suppress X-ray leakage from the opening. There is. The side leakage prevention member suppresses X-ray leakage from the gap between the opening and the transport mechanism. By combining these two types of leakage prevention members, it becomes possible to more reliably suppress the leakage of X-rays from the opening.

[Brief description of drawings]

FIG. 1 is an external view of an X-ray inspection apparatus according to the present invention.

FIG. 2 is a schematic front view of the inside of the X-ray inspection apparatus.

FIG. 3 is a schematic diagram of the vicinity of an opening on the side surface of the X-ray inspection apparatus.

FIG. 4 is a control block diagram of the X-ray inspection apparatus.

[Explanation of symbols]

1 X-ray inspection device 2 shield box 3 X-ray irradiator 4 X-ray detector 5 conveyors 6 X-ray shielding curtain 7 Side leakage prevention wall 11 openings 13 doors 14 X-ray line sensor 15 Lower shield member 16 Conveyor shielding member A Inspection item

Claims (6)

[Claims] 1. An X-ray irradiator that irradiates X-rays, a transport mechanism that is disposed below the X-ray irradiator and transports an article to be inspected, and below the X-ray irradiator and the transport mechanism. An X-ray detection unit that is arranged to detect X-rays from the X-ray irradiation unit, and an opening that covers the X-ray irradiation unit, the X-ray detection unit, and the transport mechanism and that carries in and out the article are provided. And an upper leakage prevention member that is disposed near the opening and above the transport mechanism and that prevents X-ray leakage from the top of the opening to the outside of the housing. Disposed inside the casing and on both sides of the transport mechanism,
An X-ray inspection apparatus comprising a side leakage prevention member that prevents X-ray leakage from the side of the opening to the outside of the housing. 2. The X-ray inspection apparatus according to claim 1, wherein the side leakage prevention member is arranged near the opening. 3. The X-ray inspection apparatus according to claim 1, wherein the side leakage prevention member is arranged near the X-ray detection unit. 4. The X-ray inspection apparatus according to claim 2, wherein the transport mechanism is removable, and the side leakage prevention member is mounted on a side portion of the transport mechanism. 5. The X according to claim 2, wherein the housing is provided with an opening / closing door that allows the transport mechanism to be attached / detached, and the side leakage prevention member is attached to the opening / closing door. Line inspection equipment. 6. The X-ray inspection apparatus according to claim 1, wherein a plurality of the side leakage prevention members are arranged along the carrying direction of the carrying mechanism.