JP2003121595A - Electron beam irradiation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance flexibility of the shape and the size of treatable objects to be irradiated and to effectively suppress leakage of X-rays generated from the electron beam irradiation part to the outside. SOLUTION: The electron beam irradiation apparatus comprises an irradiation chamber vessel 22 which uses an X-ray shielding material, a main carrier device 24 carrying an object to be carried in it, an electron beam accelerator 26 irradiating the object 2 with an electron beam 28, an inlet carrier 40 and an outlet carrier 50 for carry in and carry out of the object 2, through openings 30 and 32 provided in the irradiation chamber vessel 22. The inlet carrier 40 and the outlet carrier 50 are constituted individually by using the X-ray shield material and connecting with connectors 42 and 52, a plurality of carrier vessels 44 and 54 carrying the object 2 in the inside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electron beam irradiation for irradiating an object to be irradiated on a conveying device with an electron beam and subjecting the object to be irradiated to treatments such as sterilization, sterilization, insecticide, germination prevention and modification. More specifically, regarding the apparatus, the degree of freedom in the shape and size of an object to be treated that can be handled is increased, and leakage of X-rays (braking X-rays; hereinafter the same) generated from an electron beam irradiation unit to the outside. The present invention relates to improvement of means for suppressing the above.

[0002]

2. Description of the Related Art An example of this type of electron beam irradiation apparatus is described in Japanese Patent Application Laid-Open No. 8-184700.

Briefly explaining it with reference to FIG.
This electron beam irradiation apparatus is configured to irradiate an object to be irradiated 2 on a transfer device 14 provided in a transfer chamber 12 with an electron beam 18 taken out from an electron beam accelerator 16 for processing. The carry-in chamber 6 is adjacent to the carrying chamber 12, and a carry-in drum 8 is provided in the outer peripheral portion of the carry-in chamber 12 in which a plurality of receiving members 10 are erected at predetermined intervals. The irradiation object 2 carried in from the cylindrical carrying-in section 4 is held between the receiving members 10 of the carrying-in drum 8 and supplied onto the carrying device 14.

On the exit side of the transfer chamber 12, the carry-in chamber 6,
A carry-out chamber, a carry-out drum, and a carry-out section having the same structure as the carry-in drum 8 and the carry-in section 4 are provided (all are not shown).

With the irradiation of the electron beam 18, X-rays are generated from the electron beam irradiation unit 19. In this example, the wall surface of the transfer chamber 12 and the carry-in drum 8 are made of an X-ray shielding material such as lead in order to suppress the leakage of the material to the outside.

[0006]

In the electron beam irradiation apparatus, the object 2 to be irradiated is carried in through the cylindrical carrying-in section 4, and the receiving member 10 is provided upright on the outer peripheral portion of the carrying-in drum 8.
The object to be irradiated 2 is received by the carrying section 4 and the receiving device 10, particularly the receiving device 1.
If it does not match the shape of 0, it cannot be transported well. The same applies to the unloading side. Therefore,
The degree of freedom in the shape and size of the irradiated object 2 that can be handled is low.

For example, even though the electron beam irradiation apparatus is suitable for transporting a sphere of a certain size, the irradiation object 2
When potatoes, fruits, and the like have irregular sizes, and their shapes are spherical or oblate, it is difficult to convey them well.

Moreover, in the electron beam irradiation apparatus, the object to be irradiated 2
The electron beam irradiation unit 1
It is also necessary to take measures to suppress the leakage of X-rays generated from 9 to the outside.

Therefore, the present invention enhances the degree of freedom in the shape and size of the irradiated object that can be handled, and
The main purpose is to effectively suppress leakage of X-rays generated from the electron beam irradiation unit to the outside.

[0010]

One of the electron beam irradiation apparatuses according to the present invention is an irradiation chamber container formed by using an X-ray shielding material, and a main object for transporting an object to be irradiated in the irradiation chamber container. A carrier, an electron beam accelerator for irradiating an object to be irradiated on the main carrier with an electron beam, and an object to be irradiated are carried in through the opening provided on one wall surface of the irradiation chamber container and are then transferred to the main body. An apparatus for supplying to a transfer device, an inlet transfer device configured by connecting a plurality of transfer containers configured by using an X-ray shielding material and for transferring an object to be irradiated, and the main transfer device Is an apparatus for receiving an irradiation target object from the irradiation chamber and unloading the irradiation target object through an opening provided on the other wall surface of the irradiation chamber container, which is configured by using an X-ray shielding material and conveys the irradiation target object. Equipped with an outlet transfer device formed by connecting a plurality of transfer containers with a connection body It is characterized in that (claim 1).

According to the above construction, the inlet transport device and the outlet transport device have a plurality of transport containers for containing and transporting the irradiation object, and the transport containers have various shapes and sizes. Since the object to be irradiated can be inserted and transported, the degree of freedom in the shape and size of the object to be irradiated that can be handled becomes high.

Moreover, since each transfer container is constructed by using an X-ray shielding material and also serves as an X-ray shield for preventing leakage of X-rays from the opening of the irradiation chamber container, electron beam irradiation is performed. It is possible to effectively suppress the leakage of X-rays generated from the part to the outside.

At least one of the inlet transport device and the outlet transport device is provided with a plurality of partition plates, which are constructed by using an X-ray shielding material, instead of the transport container, with a space between them. It may be configured by connecting with a connecting body in the state (claim 2).

Since objects to be irradiated having various shapes and sizes can be inserted and conveyed also between such partition plates, the degree of freedom in the shape and size of the objects to be handled that can be handled becomes high. .

Moreover, since each partition plate is made of an X-ray shielding material and also serves as an X-ray shield, the leakage of X-rays generated from the electron beam irradiation unit to the outside is effectively suppressed. can do.

Even if the outside of the portion through which the entrance transport device and the exit transport device pass through the opening of the irradiation chamber container is covered with an entrance shield and an exit shield made of an X-ray shield, respectively. Good (Claim 3).

By doing so, the X-rays which are about to leak from the gap of the opening of the irradiation chamber container can be further shielded by these entrance and exit shields, so that the X-rays leak to the outside. Can be suppressed more effectively.

[0018]

1 is a sectional view showing an example of an electron beam irradiation apparatus according to the present invention. FIG. 2 is an enlarged perspective view showing a part of the entrance conveyance device in FIG.

This electron beam irradiation apparatus includes an irradiation chamber container 22 constructed by using an X-ray shielding material, and an object to be irradiated as described above in the irradiation chamber container 22 provided in the irradiation chamber container 22. 2 is provided with a main transport device 24 that transports 2 in a fixed direction (the direction of arrow B in this example), and an electron beam accelerator 26 that irradiates each irradiation target 2 on this main transport device 24 with an electron beam 28.

The irradiation chamber container 22 is made of, for example, an X-ray shielding material such as lead, iron or the like, and shields the X-rays generated from the electron beam irradiation unit 29 with the irradiation of the electron beam 28. It serves to reduce the intensity of X-rays leaking to the outside of the irradiation chamber container 22. In this specification, "using" means that the X-ray shielding material may be used alone, or the X-ray shielding material and another material may be combined.

The main conveyor 24 is a conveyor such as a belt conveyor or a roller conveyor. In the case of a roller conveyor, it is sufficient to use a roller conveyor having a roller interval so that the irradiation target 2 does not drop.

The electron beam accelerator 26 may be of a scanning type in which the electron beam 28 is scanned and taken out in a direction orthogonal to the transport direction (direction of arrow B) of the irradiation object 2, or an electron beam having a long shape in the same direction. A non-scanning type (area beam type) which takes out 28 without scanning may be used.

On one side of the irradiation chamber container 22, there is arranged an entrance transfer device 40 which carries in the irradiation object 2 through an opening 30 provided on the wall surface thereof and supplies it to the main transfer device 24. . Referring to FIG. 2 as well, the entrance transport device 40 is formed by connecting a plurality of transport containers 44, which are configured by using an X-ray shielding material, and which transports the irradiation target object 2 by a coupling body 42. Is rotated by the rotary drum 46 and moved as indicated by arrow A.

On the other side of the irradiation chamber container 22, there is arranged an outlet transfer device 50 which receives the object to be irradiated 2 from the main transfer device 24 and carries it out through an opening 32 provided on the wall surface on the same side. There is. Similar to the entrance transport device 40, the exit transport device 50 is also configured by using an X-ray shielding material, and a plurality of transport containers 54 that contain and transport the irradiation target 2 are coupled by a coupling body 52. This is rotated by the rotary drum 56 and moved as indicated by arrow C.

In this example, each of the transfer containers 44 and 54 is a box-shaped container (bucket) having an open top. Each of the transport containers 44 and 54 has a structure in which, for example, stainless steel, plastic, or the like is bonded with lead, which is an X-ray shielding material. The same applies to partition plates 48 and 58 described later. The thickness of lead may be determined according to the required X-ray shielding ability.

The connecting members 42 and 52 may be belts as in the example shown in FIG. 2 or chains.

The openings 30 and 32 of the irradiation chamber container 22
Is the wall surface of the irradiation chamber container 22 and the transfer containers 44 and 54.
(Or partition plates 48 and 58 described later) is preferably made as small as possible in order to reduce the gap between them and the leakage of X-rays therefrom.

When the transport container 44 of the entrance transport device 40 comes to the side of the rotary drum 46, the irradiation object 2 naturally rolls out of the transport container 44, so that the end of the main transport device 24 is moved toward the transport container 44. By placing it down,
The irradiation object 2 can be supplied onto the main carrier 24. At this time, if necessary, as in this example, a guide plate 34 for guiding the irradiated object 2 rolled out of the transport container 44 onto the main transport device 24 may be provided.

When the irradiated object 2 reaches the other end of the main carrier device, the irradiated object 2 naturally drops from there. Therefore, the end part of the outlet carrier device 50 is located below the end part of the main carrier device 24. By arranging it at the position, the irradiation target 2 can be received from the main transport device 24. If necessary, a guide plate may be provided on this side to guide the irradiated object 2 falling from the main carrier device 24 to the carrier container 54 of the exit carrier device 50. In addition, it is preferable that the interval between the respective transport containers 54 is made small so that the irradiation target object 2 is not clogged, and by doing so, the transport efficiency becomes high.

If necessary, a drop prevention plate for preventing the irradiated object 2 from falling to the left or right may be provided on both the left and right sides of the main transport device 24, the guide plate 34, and the like. Figure 3
The same applies to the inlet transport device 40 and the outlet transport device 50 of the example shown in FIG.

In the electron beam irradiation apparatus of this example, the outside of the portion where the entrance conveyance device 40 and the exit conveyance device 50 pass through the openings 30 and 32 of the irradiation chamber container 22 is further provided with, for example, the X-ray shielding material as described above. Are covered with a box-shaped entrance shield 62 and an exit shield 66, which are configured by using the same as the above (the same applies to the example of FIG. 3). The entrance shield 62 and the exit shield 66 are provided in the entrance conveyance device 40 and the exit conveyance device 50.
It has openings 64 and 68, respectively, which allow its movement through.

The openings 64 and 66 are also connected to the entrance shield 62 and the exit shield 66 and the transfer containers 44 and 54.
(Or partition plates 48 and 58 described later) is preferably made as small as possible in order to reduce the gap between them and the leakage of X-rays therefrom.

According to this electron beam irradiation apparatus, the entrance transport device 40 and the exit transport device 50 have a plurality of transport containers 44 and 54 for containing and transporting the irradiation object 2. Since the object to be irradiated 2 having various shapes and sizes can be contained and transported in the unit 54, the degree of freedom in the shape and size of the object to be irradiated 2 that can be handled becomes high.

For example, even when the object 2 to be irradiated has irregular sizes such as potatoes and fruits, and the shape thereof is spherical or oblate, the object 2 to be irradiated is successfully conveyed. can do.

Moreover, each of the transfer containers 44 and 54 is made of an X-ray shielding material, and also serves as an X-ray shield for preventing leakage of X-rays from the openings 30 and 32 of the irradiation chamber container 22. Therefore, leakage of X-rays generated from the electron beam irradiation unit 29 to the outside can be effectively suppressed.

Further, if the entrance shield 62 and the exit shield 66 as described above are provided as in this example, it tends to leak from the above-mentioned gaps existing in the openings 30, 32 of the irradiation chamber container 22. Since the X-rays can be further shielded by the entrance shield 62 and the exit shield 66, the leakage of X-rays to the outside can be suppressed more effectively.

For example, the energy of the electron beam 28 is 300
In the case of a relatively low energy of about keV or less, the generated X-ray dose is also relatively small.
It is possible to suppress the leakage X-ray dose to the outside to a specified value or less without providing the 2 and the outlet shield 66. As long as the energy of the electron beam is at that level, similar shielding could be performed in the above-mentioned conventional device.

On the other hand, the energy of the electron beam 28 is 500 k.
In the case of a relatively high energy of about eV or more, it is preferable to provide the above-described entrance shield 62 and exit shield 66, and in this case as well, the leakage X-ray dose to the outside is equal to or less than the specified value. It is easy to keep If the electron beam energy reaches this level, it will be difficult for the above-described conventional device to sufficiently shield the X-rays.

In FIG. 3, a plurality of partition plates 48 and 40, which are constructed by using the X-ray shielding material as described above, instead of the transport containers 44 and 54, are provided in both the inlet transport device 40 and the outlet transport device 50. An example configured using 58 is shown.
The partition plates 48 are also connected to each other by the connecting body 42 in a state of standing up with a space between them, also referring to FIG. 4. The same applies to the partition plate 58. In the case of this example, it is preferable to use belts for the connecting bodies 42 and 52 from the viewpoint of preventing the irradiated object 2 from falling.

Since the irradiation object 2 of various shapes and sizes can be inserted and conveyed between the partition plates 48 and 58, the shape and size of the irradiation object 2 can be handled. You have more freedom.

Moreover, since each of the partition plates 48 and 58 is made of an X-ray shielding material and also serves as an X-ray shield, leakage of X-rays generated from the electron beam irradiation unit 29 to the outside is prevented. It can be effectively suppressed.

Inlet carrier device 40 and outlet carrier device 50
One of the two is a transport container 44 (or 5) as in the example of FIG.
4) may be used, and the other may use the partition plate 48 (or 58) as in the example of FIG. That is,
The example of FIG. 1 and the example of FIG. 3 may be combined.

[0043]

Since the present invention is configured as described above, it has the following effects.

According to the first aspect of the present invention, each of the inlet transport device and the outlet transport device has a plurality of transport containers for containing and transporting the object to be irradiated. Since the irradiation target having a shape and a size can be inserted and conveyed, the flexibility of the shape and the size of the irradiation target that can be handled becomes high.

Moreover, since each transfer container is constructed by using an X-ray shielding material and also serves as an X-ray shield for preventing leakage of X-rays from the opening of the irradiation chamber container, electron beam irradiation is performed. It is possible to effectively suppress the leakage of X-rays generated from the part to the outside.

According to the second aspect of the present invention, since irradiation objects of various shapes and sizes can be inserted and conveyed between the partition plates as described above, the irradiation objects that can be handled can be handled. The degree of freedom in the shape and size of is increased.

Moreover, since each partition plate is made of an X-ray shielding material and also serves as an X-ray shield, leakage of X-rays generated from the electron beam irradiation unit to the outside is effectively suppressed. can do.

According to the third aspect of the invention, the X-rays that are about to leak from the gap of the opening of the irradiation chamber container can be further shielded by the entrance shield and the exit shield, so that the X-rays are exposed to the outside. Can be suppressed more effectively.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an electron beam irradiation apparatus according to the present invention.

FIG. 2 is an enlarged perspective view showing a part of the entrance conveyance device in FIG.

FIG. 3 is a sectional view showing another example of the electron beam irradiation apparatus according to the present invention.

FIG. 4 is an enlarged perspective view showing a part of the entrance conveyance device in FIG.

FIG. 5 is a sectional view showing an example of an inlet half of a conventional electron beam irradiation apparatus.

[Explanation of symbols]

2 irradiated object 22 Irradiation chamber container 24 Main carrier 26 electron beam accelerator 28 electron beams 30, 32 openings 40 entrance carrier 42 connected body 44 Transport container 48 partition boards 50 exit carrier 52 Connected body 54 Transport Container 58 Partition 62 entrance shield 66 Exit shield

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G21K 5/10 G21K 5/10 C F term (reference) 2B121 AA11 AA20 DA23 EA30 FA15 4C058 AA01 BB06 KK02 KK03 KK04 KK05 KK21 KK33

Claims (3)

[Claims] 1. An irradiation chamber container configured by using an X-ray shielding material, a main transfer device for transferring an object to be irradiated in the irradiation chamber container, and an electron beam to the object to be irradiated on the main transfer device. An electron beam accelerator for irradiating, and a device for carrying in an object to be irradiated through an opening provided in one wall surface of the irradiation chamber container and supplying it to the main carrier, using an X-ray shielding material. An entrance transport device configured by connecting a plurality of transport containers that are configured to contain and transport an irradiation target object, and an irradiation target object that receives the irradiation target object from the main transfer device and transfers it to the other wall surface of the irradiation chamber container A device for carrying out through an opening provided in the container, which is configured by using an X-ray shielding material, and which is formed by connecting a plurality of transport containers for containing and transporting an irradiation target with a coupling body. An electron beam irradiation apparatus, comprising: 2. At least one of the inlet transport device and the outlet transport device is provided with a plurality of partition plates, which are configured by using an X-ray shielding material, in place of the transport container, with a space between them. The electron beam irradiation apparatus according to claim 1, wherein the electron beam irradiation apparatus is formed by connecting with the connecting body in an upright state. 3. The entrance transport device covers the outside of a portion passing through the opening of the irradiation chamber container while allowing the movement of the entrance transport device, and is configured by using an X-ray shielding material. The X-ray shielding material covers the entrance shield and the outside of the portion of the exit transport device passing through the opening of the irradiation chamber container while allowing the movement of the exit transport device. The electron beam irradiation apparatus according to claim 1, further comprising an outlet shield.