JP2003130999A - Carrier of electron beam irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carrier of electron beam irradiation device applicable to a plurality of kinds of irradiation objects and capable of easily placing on a production line as well. SOLUTION: The carrier of electron beam irradiation device provided with a shield plate on a conveyer 12 conveying irradiation objects 30 for sterilizing- processing with electron beam irradiation comprises a carrying tray 11 for putting the irradiation objects 30 on the conveyer 12 and carrying. The tray 11 comprises, in the front and the back, shield plates 13 consisting of a front and a back plates preventing leaked radiation, a support tool 16 of which the surface of contacting to the irradiation objects is formed to fit the shape of bottom or side surfaces of the irradiation objects, and a metal net for detaching prevention formed with a metal net for detaching prevention 17 and the shield plate 13 at at least one side of the carrying tray 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam irradiation apparatus for irradiating an electron beam to medical instruments, food and drink containers, and mail items containing anthrax to achieve initial purposes such as sterilization. In particular, the present invention relates to a transport facility for a small electron beam irradiation apparatus that can be incorporated into an existing production line.

[0002]

2. Description of the Related Art Products such as medical instruments and food and drink containers are required to be sufficiently sterilized for shipping as products. Although various methods are used for these sterilization methods, among them, the electron beam irradiation sterilization method is popular because of advantages such as short processing time, continuous processing, and high penetrating power. Such electron beam sterilization includes, in addition to sterilization of the medical instruments, food and drink containers, etc.,
It is also possible to sterilize pathogens harmful to the human body, such as anthrax, which has recently become a problem. The electron beam irradiation apparatus used in such an electron beam irradiation sterilization method is an electron beam accelerator system that generates an electron beam and irradiates an irradiation object, a conveyance system such as a conveyor that conveys the irradiation object to an electron beam irradiation region. , A radiation shielding system such as a shielding wall for preventing leakage of the radiation generated by the electron beam irradiation to the outside.

Generally, the accelerating energy of the electron beam used for sterilization requires an output of at least 1 MeV,
A high output device may be used up to about 10 MeV. Therefore, it is necessary to prevent the radiation generated by the electron beam irradiation from leaking to the outside by surrounding the electron beam irradiation part with a thick shielding wall formed of concrete, lead, iron or the like. At this time, in order to suppress the radiation below the allowable level, the radiation must be reflected and deflected at least twice, and the conventional shielding wall has a labyrinth structure to prevent the radiation from leaking. Further, in such an apparatus, a maintenance space is provided so that a worker can work in the shielded room for maintenance of the electron beam accelerator system provided in the shielded room, and as a result, the electron beam irradiation apparatus itself. Tended to grow in size.

However, such an apparatus is difficult to install on the production line, and it is not possible to deal with a change in the layout of the factory. Therefore,
US Pat. No. 6,191,424 proposes a miniaturized in-line type electron beam irradiation apparatus which can be easily installed on a production line. FIG. 5 shows an electron beam irradiation apparatus according to the invention. The configuration of the electron beam irradiation device is
A first shielding means 018 made of concrete or the like, an electron beam irradiation device 019 installed in the space 021 of the first shielding means 018, a conveyor system 020 for conveying an irradiation object, and the first shielding means. It comprises a transport path 022 provided, a container 023 on which an object to be irradiated is placed, and an elliptical track 024 through which the container is transported.

FIG. 6 shows a plan view (a) and a side view (b) of a container of the electron beam irradiation apparatus. The container 023 has a function of transporting the irradiation target object, and a front wall 026 and a rear wall 02 arranged in front and rear parts thereof.
The second shield means 7 also has a function of preventing leakage of radiation. The front and rear walls 026 and 027 are made of metal such as steel, lead, and tungsten that have low radiation permeability, and are formed to have substantially the same size as the opening of the transport path 022. Therefore, it is possible to reduce the leakage of the radiation from the transport path 022, and it is possible to reduce the radiation leaked to the outside to an allowable level by using the first shielding means together. With such a configuration, the electron beam irradiation apparatus as a whole can be downsized, and since it is a simple facility, it can be easily installed on the production line.

[0006]

By the way, in the electron beam irradiation apparatus used for sterilization, particularly in the in-line type electron beam irradiation apparatus as in the above-mentioned prior art, the products to be processed are often small in number and many kinds. . As described above, in order to deal with a plurality of types of objects to be irradiated, a device for controlling the electron beam emission dose, a device for controlling the conveyor transport speed to keep the irradiation dose constant, and the like are provided. It is difficult to reliably irradiate an irradiation object having various shapes with an electron beam only by stabilizing the irradiation dose to the irradiation object in the apparatus of (1). That is, the object to be irradiated is not fixed at a fixed position due to the vibration of the conveyor or the centrifugal force at the conveyor bending portion,
There is a problem that the electron beam is not accurately emitted. Therefore, in the conventional electron beam irradiation apparatus, only one kind of object to be irradiated is conveyed per set of conveying equipment.

On the other hand, in the in-line type electron beam irradiation apparatus, as described above, plural kinds of objects to be irradiated have to be processed, and it is necessary to install or replace the transfer equipment for each product type. At present, the production efficiency was very poor. The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a transport facility for an electron beam irradiation apparatus that can be easily installed on a production line and can be adapted to a plurality of types of irradiation targets.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a shield means on a conveyor for carrying an irradiation object to be sterilized by electron beam irradiation. In the transport facility of the electron beam irradiation apparatus provided, a tray for placing and transporting an object to be irradiated is provided on the conveyor, and the tray is a shielding plate that is the shielding means provided at the front and rear portions of the tray, The object to be irradiated is fixed, and a surface of the fixing means that comes into contact with the object to be irradiated is formed in conformity with a shape of a bottom surface or a side surface of the object to be irradiated.

Further, the invention according to claim 2 is characterized in that, on a conveyor for carrying an irradiation object to be sterilized by electron beam irradiation,
In the transportation facility of the electron beam irradiation device equipped with the shielding means,
A tray for placing and transporting an irradiation object on the conveyor is provided, and the tray includes a shielding plate that is the shielding means provided at the front and rear portions of the tray, and a fixing means for the irradiation object. It is characterized in that the fixing means is formed of a pressure contact portion for holding the irradiation target object or a supporting surface by gravity.

According to the invention, the electron beam irradiation device is downsized by providing the shielding means formed on the transfer conveyor with a material having a low radiation transmitting power such as lead and iron, and the shielding means. 3. A support is provided on a transport tray for mounting and transporting the object to be irradiated, and further, on the tray, a support tool formed according to the shape of the object to be irradiated as described in claim 1 or claim 3. By providing a support tool that is gripped by pressure contact or a support tool that is fixed by gravity as described above, it is possible to reliably fix an object to be irradiated having different shapes to the tray, and to perform irradiation with high accuracy. As a result, it is possible to provide a transfer facility for an electron beam irradiation apparatus that can simultaneously sterilize a plurality of types of irradiation objects.

Further, the invention according to claim 3 is characterized in that the fixing means according to claim 1 or 2 includes a fall prevention surface formed so as to surround at least three surfaces of the irradiation object. . This is achieved by blocking at least one side surface of the transport tray with a wire mesh or the like in addition to the shielding plates provided at the front and rear portions of the transport tray, so that at least 3
A falling surface that surrounds the surface is formed, and even an irradiation target having a complicated shape can be transported without dropping from the transport tray.

It is preferable that the fixing means is formed of a material having a low effective atomic number, and epoxy, aluminum or the like is particularly preferable. According to this, by using a material with a low effective atomic number, the dose can be guaranteed without hindering the electron beam penetrating power to the irradiated object, and there is a risk of activation due to repeated irradiation. There is no. Furthermore, by appropriately selecting the support member according to the type of the object to be irradiated, it is possible to easily sterilize a plurality of kinds of objects to be irradiated at the same time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative positions, etc. of the components described in this embodiment are not intended to limit the scope of the present invention thereto unless specifically stated otherwise, and are merely illustrative examples. Not too much. FIG. 1 is a cross-sectional view showing a transfer facility of an electron beam irradiation apparatus according to an embodiment of the present invention, FIG. 2 is a perspective view of a transfer tray according to an embodiment of the present invention (a), an enlarged perspective view of a support (b), and FIG. 3 is a side view of the carrying tray on which the object to be irradiated is fixed, and FIG. 4 is a plan view showing the overall configuration of the system including the electron beam irradiation apparatus according to the embodiment of the present invention.

In the present embodiment, the electron beam irradiation apparatus main body 10 supplies an electron gun for emitting an electron beam, an accelerating tube for accelerating the emitted electron beam, and microwave energy for accelerating the electron beam. It consists of a klystron and an electron beam irradiation unit that irradiates an irradiation object with an electron beam. It can be used from large instruments with an acceleration energy of 10 MeV to small instruments with an acceleration energy of about 1 MeV, depending on the installation area, type of object to be illuminated, etc. select. Further, in such an embodiment, the irradiated object to be sterilized is not particularly limited to surgical gowns, medical instruments such as infusion bags, beverage containers such as PET bottles, etc. Seed products can be continuously processed.

First, the overall system configuration of this embodiment will be described from the plan view shown in FIG. The electron beam irradiation apparatus includes a belt conveyor 25, a carry-in / out means including a pusher 27 and a puller 26, and a conveyor 12 that conveys an object 30 to be irradiated from the belt conveyor 25 and conveys the object 30 through an irradiation area. A system, an irradiation system including the electron beam irradiation apparatus main body 10, a shielding wall 14 and a movable wall that are first shielding means that prevent leakage of radiation so as to surround the electron beam irradiation apparatus main body 10 and the conveyor 12. It consists of 15 shielding systems.

In the transfer system, the belt conveyor 25 is connected to another step of the production line for the product to be irradiated, and the irradiated object 30 to be transferred is pushed by the pusher 27 into an elliptical track type transfer conveyor 12. Reprinted in.
The transfer conveyor 12 circulates the irradiation object 30, and sterilization is performed by the electron beam irradiation device 10 provided in the linear portion of the transfer conveyor 12. The conveyor 12 is provided with a plurality of shielding plates 13 which are second shielding means. The shielding plate 13 is formed of a material having a low radiation transmitting power such as lead and iron, and has a function of preventing leakage of radiation in the shielding wall 14 in the conveyor passage direction.

The shield plate 13 used for the second shield means is preferably formed in a tray shape as shown in FIGS. FIG. 1 shows a sectional view of a transportation facility including the irradiation system part. In FIG.
The shielding wall 14 formed of a shielding material such as concrete,
An electron beam irradiation apparatus main body installation section 18, which is an installation space for the electron beam irradiation apparatus main body 10, and a transfer passage 19 for disposing the transfer conveyor 12 are provided.

A plurality of trays 11 on which the objects 30 to be irradiated are placed are carried on the carrying conveyor 12 in the direction of the arrow in FIG. As in the present embodiment, in the in-line type electron beam irradiation apparatus connected to another manufacturing process, there are many cases where the irradiation target object 30 which is the product to be sterilized is a small amount and a plurality of kinds. Then, the tray 11 provided with the fixing means is used to stably irradiate different kinds of products. Incidentally, the current amount control means,
Alternatively, it is preferable to provide a transportation speed control means or the like on the transportation conveyor 12 and appropriately adjust the energy value and the irradiation amount of the electron beam according to the type and size of the irradiation object.

A carrying tray 11 provided with the fixing means is shown in FIGS. The transport tray 11 has a shield plate 13 made of lead, iron, or the like disposed in the front and rear portions thereof, and has a bottom made of a material that is hard to be activated like the shield plate 13.
The shielding plate 13 needs to have a wall thickness that does not allow the radiation to pass therethrough in order to prevent the radiation from being scattered. However, since it is not necessary to prevent the radiation from passing in the vertical direction, the durability of the bottom plate is maintained. It should be thick enough.

The shield plate 13 has an object 3 to be irradiated.
A support 16 for fixing 0 is provided. As shown in FIG. 2A, the support 16 is a support 1 in which an object 30 to be irradiated is placed and then a cylinder is projected to press and fix the cylinder.
6a, as shown in FIG. 2 (b), a support 16b for fixing an object to be irradiated having a curved surface such as a bottle or a plastic bottle is selected according to the object to be sterilized. The supports 16a and 16b are arranged on the transfer tray 11 and may of course be provided on the bottom surface of the tray 11.

FIG. 3 is a side view when the object 30 to be irradiated is actually placed on the transfer tray 11, and FIG. 3A is a wire mesh 1 for preventing the object 30 to be irradiated placed on the transfer tray 11 from falling off.
7 and (b) are fixed by a support tool 16c, and (c) is a fall prevention wire mesh 17 and a support tool 1.
6 shows the transport tray 11 when fixed by 6a. The drop-prevention wire net 17 is provided on at least one side surface of the transport tray, is formed so as to surround at least three surfaces of the irradiation target together with the shielding plate 13, and is prevented from falling off during transport of the transport conveyor 12. It can be prevented. At this time, if the belt conveyor 12 is tilted toward the wire mesh side, the irradiation object 30 is biased toward the wire mesh side by gravity, and the irradiation object can be prevented from moving in the tray.

It is also possible to prevent the irradiated object 30 from falling off by providing the falling prevention wire nets 17 on both side surfaces of the transport tray 11 and placing the irradiated object 30 from above. is there. FIG. 3 (b) is a case where the support 16c is installed diagonally upward, and is preferably used when the bottom surface is unstable like the irradiated object 30b. It is preferable to appropriately select the method for doing so. Further, FIG. 3 (c) shows a case where the wire net 17 and the pressure contact support 16a are used in combination, whereby the irradiation object 30a can be more reliably fixed. It is preferable that the support 16 and the drop-prevention wire net 17 are detachably formed, and they may be replaced according to the irradiation target to be sterilized. These supports and the wire mesh for preventing fall
It is preferably formed of a material having a low effective atomic number,
Particularly, it is preferable to use epoxy, aluminum or the like.
A caster (not shown) may be attached to the bottom surface of the transfer tray 11 to serve as an auxiliary transfer means or a main transfer means.

[0023]

As described above, according to the present invention, even irradiation objects having different shapes can be reliably fixed on the transport tray, and irradiation with high accuracy can be performed. At the same time, it is possible to provide an electron beam irradiation apparatus that can be sterilized at the same time. Further, in addition to the shielding plates provided at the front and rear portions of the transfer tray, at least one side surface of the transfer tray is closed to form a drop surface that surrounds at least three surfaces of the irradiation target object, thereby forming a complicated shape. It is possible to reliably convey even the object to be irradiated which has the above-mentioned feature, without dropping from the carrying tray.

Further, by using a material having a low effective atomic number for the fixing means, the absorbed dose to the irradiated object can be guaranteed without inhibiting the electron beam penetrating power of the irradiated object, and There is no danger of activation due to overlapping irradiation. Furthermore, by appropriately selecting the support member according to the type of the object to be irradiated, it becomes possible to easily sterilize plural kinds of objects to be irradiated simultaneously.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a transfer facility of an electron beam irradiation apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view (a) of a carrying tray and an enlarged perspective view (b) of a support according to the embodiment of the present invention.

FIG. 3 is a side view of a carrying tray on which an object to be irradiated is fixed.

FIG. 4 is a plan view showing an overall configuration of a system including an electron beam irradiation device according to an embodiment of the present invention.

FIG. 5 is a plan view of an in-line type electron beam irradiation apparatus in the related art.

6A and 6B are a plan view and a side view of a container of the electron beam irradiation apparatus of FIG.

[Explanation of symbols]

10 Electron beam irradiation device body 11 Transport tray 12 Conveyor 13 Shield 14 Shielding wall 15 Movable wall 16 Support 17 Fall prevention wire mesh 18 Electron Beam Irradiator Main Unit Installation Section 19 Transport passage 25 belt conveyor 26 puller 27 pushers 30 irradiation target

Continued front page    (72) Inventor Takashi Yamakawa             10 Oemachi, Minato-ku, Nagoya-shi Mitsubishi Heavy Industries Ltd.             Ceremony Company Nagoya Aerospace Systems Works (72) Inventor Yuichiro Kano             10 Oemachi, Minato-ku, Nagoya-shi Mitsubishi Heavy Industries Ltd.             Ceremony Company Nagoya Aerospace Systems Works F term (reference) 4C058 AA12 AA21 BB06 KK01 KK33

Claims (5)

[Claims] 1. In a transport facility of an electron beam irradiation apparatus equipped with a shielding means on a conveyor for transporting an object to be sterilized by electron beam irradiation, the object to be irradiated is placed on the conveyor and transported. A tray is provided, and the tray includes a shielding plate that is the shielding means provided at the front and rear of the tray, and a fixing means for the irradiation target, and a surface of the fixing means that contacts the irradiation target is A transport facility for an electron beam irradiation device, which is formed according to the shape of the bottom surface or side surface of an object to be irradiated. 2. An electron beam irradiating apparatus equipped with a shielding means on a conveyor for transporting an irradiation object to be sterilized by electron beam irradiation, and the irradiation object is placed and transported on the conveyor. A tray is provided, and the tray includes a shielding plate that is the shielding means provided at the front and rear of the tray, and a fixing means for the irradiation target, and the fixing means holds the irradiation target by a press contact portion. Alternatively, it is a transportation facility of an electron beam irradiation device, which is formed from a supporting surface by gravity. 3. The transfer facility for an electron beam irradiation apparatus according to claim 1, wherein the fixing means includes a drop-out prevention surface formed so as to surround at least three surfaces of the irradiation object. . 4. The transport facility for an electron beam irradiation apparatus according to claim 1, wherein the fixing means is made of a material having a low effective atomic number. 5. The transport facility for an electron beam irradiation apparatus according to claim 1, wherein the supporting member is appropriately selected according to the type of the object to be irradiated.