JPH0658399U - Electron beam irradiation device - Google Patents

Abstract

(57) [Summary] [Purpose] To shield the transfer port of the irradiated object by using the transfer roll. [Constitution] The irradiation target 6 is guided by a leaded carrier roll 11 through carrier ports 8, 8 ′ formed in the shield 3,
It is transported to the preliminary chamber 2 and the irradiation chamber 1. Two leaded rolls are arranged so as to sandwich each transport port and cover the transport ports. The object to be irradiated is conveyed between the two rolls while being inclined through the peripheral surface portions of the two conveyance rolls in different directions. The transport roll can be made small, the two transport ports 8 and 8'can be provided at substantially the same height position, and the preliminary chamber can be downsized. Flapping of the irradiated object at the transfer port can be suppressed, and the width of the transfer port can be reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electron beam irradiation apparatus in which leakage of X-rays from a transfer port for an irradiation target formed on a shield is reduced.

[0002]

[Prior art]

 The electron beam irradiation apparatus is constructed so that the entire X-rays are covered with a shielding material so that the X-rays generated inside do not leak outside. FIG. 3 is a cross-sectional view showing an example of the electron beam irradiation device, and the irradiation chamber 1 and the preliminary chamber 2 are formed as a shield room by a shield 3 such as lead or concrete. An electron beam source 4 having an electron gun and an acceleration tube is provided above the irradiation chamber 1, and a spot-shaped electron beam from the electron beam source is transferred into the irradiation chamber 1 by the magnetic field of the scanning coil 5. The irradiated object 6 is scanned in the width direction, and the electron beam is applied to the irradiated object through the scanning tube 7. The irradiation object 6 is guided and conveyed by a conveyance roll 9 through slit-shaped conveyance ports 8 and 8 ′ formed in the shield 3. Although FIG. 3 shows the right half of the electron beam irradiation apparatus, the left side of the dashed line is also constructed to be substantially symmetrical.

When an electron beam hits a substance, bremsstrahlung and X-rays are generated. An X-ray is generated from the irradiation target 6, and a beam catcher 10 that absorbs an electron beam that has passed through the irradiation target and an electron beam that does not hit the irradiation target is provided below the irradiation target 6 in the irradiation chamber 1. X-rays are still generated. The generated X-rays are scattered, reflected and attenuated in the irradiation chamber 1 and attenuated in the process of passing through the shield 3, but do not attenuate from the transfer port 8'that allows the irradiated object 6 to enter and leave the irradiation chamber. Since there are leaking X-rays, the spare chambers 2 are set up on both sides of the irradiation chamber, and the irradiation object is carried in and out through the transfer port 8. For the X-rays leaking from the transfer port 8, for example, Even within 2, the light is reflected a certain number of times or more, and is sufficiently attenuated so that the dose becomes less than the allowable dose.

[0004]

As described above, the electron beam irradiation apparatus is configured to reflect the generated X-rays in the irradiation chamber 1 and the auxiliary chamber 2 at least three times or more and attenuate them. In this respect, the installation positions of the transfer port 8 and the transfer port 8'also have a height difference so that the X-rays that finally leak from the transfer port 8 to the outside of the electron beam irradiation device are sufficiently reflected in the spare room. However, the reserve room is designed so that it will be attenuated, and the reserve room will inevitably become large, and the equipment weight and installation area will increase.

An object of the present invention is to provide an electron beam irradiation apparatus in which a preparatory chamber is downsized by shielding a transfer port of an irradiation target formed on a shield with a transfer roll. Is.

[0006]

[Means for Solving the Problems]

 The present invention sandwiches the transfer port of the irradiated object formed on the shield, and has two leaded transfer rolls at a position covering the transfer port. It is characterized in that the rolls are conveyed while being inclined through the peripheral surface portions in different directions.

[0007]

[Action]

 Since the two lead-containing transport rolls are provided on both sides of the transport port so as to cover them, the X-rays leaking from the transport port can be effectively shielded by the lead-based transport roll.

[0008]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of the embodiment, and the same reference numerals as those in FIG. 3 indicate the same parts. The shield 3 that forms the irradiation chamber 1 and the auxiliary chamber 2 as a shield room is provided with slit-shaped transfer ports 8 and 8'of the irradiation target object, and the transfer ports are provided on both sides of each transfer port. Two leaded rolls 11 with lead are respectively arranged at a position to cover and cover them. The object 6 to be irradiated is conveyed between the two leaded rolls 11 with lead arranged on both sides of each of the feed ports 8 and 8'inclining through the peripheral surfaces of the two rolls in different directions.

FIG. 2 shows a sectional view of an example of the leaded carrier roll 11. A cylindrical roll member 13 made of, for example, stainless steel is attached to the roll shaft 12 via a disc-shaped support member 14, and a lead plate 15 is provided inside the cylindrical roll member. Is attenuated by a lead plate with a large specific gravity.

As described above, the irradiation target 6 is conveyed between the two transfer rolls 11 on both sides of the transfer ports 8 and 8 ′ of the irradiation target 6 while being inclined through the peripheral surface portions of the both transfer rolls in different directions. Thus, the object to be irradiated is transported between the transport rolls 11 located on both sides of the transport port 8'in the conventional apparatus of FIG. 3 through the peripheral surface portions of these rolls in the same direction. Compared with the case, the holding angle θ of the irradiated object and the diameter of the transport roll on each transport roll can be reduced. As a result, the transport rolls can be placed close to the transport port, and the two transport rolls 8 and 8'are covered with two transport rolls 11 so that the two transport ports are located at substantially the same height. The X-ray can be shielded and attenuated by the transport roll that covers the transport port. Therefore, the height and width of the preliminary chamber 2 can be shortened, and the preliminary chamber can be downsized. Although there are X-rays that pass through the transfer ports 8 and 8'as indicated by the arrow A, the X-rays are frequently reflected in the irradiation chamber 1 and the preliminary chamber 2, and can be sufficiently attenuated. .

Then, the irradiation target 6 is slanted and stretched between the transfer rolls 11 on both sides of the transfer ports 8 and 8 ′, and the distance between the both rolls is shortened. Flapping of the irradiated object at the transfer opening can be suppressed, and the slit width at the transfer opening can be reduced.

[0012]

[Effect of device]

 As described above, the present invention sandwiches the transfer port of the object to be irradiated, arranges two lead-containing transfer rolls at a position covering the transfer port, and transfers the irradiation target between both transfer rolls. Since the rolls are conveyed while being inclined through the peripheral surface portions in different directions, the X-rays passing through the transport ports can be effectively shielded by these transport rolls, and the preliminary chamber can be downsized. Further, X-rays that are not shielded by the transport roll are also reflected in the auxiliary chamber, so that X-rays that finally leak from the transport port to the outside of the electron beam irradiation device can be sufficiently attenuated.

Further, the object to be irradiated is conveyed between the two conveying rolls provided on both sides of the conveying port while being inclined while passing through the peripheral surface portions of the both conveying rolls in different directions. It is possible to suppress flapping of the irradiation target object and to smoothly convey the irradiation target, and the width of the conveyance port can be reduced accordingly. Therefore, X-rays leaking from the conveyance port can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of a leaded carrier roll.

FIG. 3 is a cross-sectional view showing an example of a conventional device.

[Explanation of symbols]

 1 Irradiation room 2 Preliminary room 6 Irradiation object 8,8 'Transfer port 11 Leaded transfer roll

Claims (1)

[Scope of utility model registration request] 1. A transport port for an irradiation target formed on a shield is sandwiched, and two lead transport rolls are provided at a position covering the transport port. An electron beam irradiating device, characterized in that it is configured so as to be conveyed while being inclined via peripheral surfaces in different directions of a conveyor roll.