JP3268741B2 - Electron beam irradiation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam irradiating apparatus, and more particularly to an electron beam irradiating apparatus capable of irradiating a side or a lower surface of an object having a thickness with a required electron beam.

[0002]

2. Description of the Related Art Electron beam irradiation, which started with electron beam cross-linking and electron sterilization of polyethylene, has been expanded due to the expansion of application fields and advances in accelerators.
It is widely used for manufacturing special heat-resistant members.

Since an electron beam generally travels in a straight line,
In the case of an irradiated object having a thickness, the surface within a certain angle from the traveling direction of the electron beam is sufficiently irradiated, but when the angle is larger, the irradiation amount is reduced, and when the angle is more than a certain angle, the irradiation is completely stopped. Will not be.

Therefore, conventionally, the number of electron guns has been increased according to the required irradiation surface. In FIG. 7, two electron guns 22 are used to irradiate a sufficient electron beam 24 to both side surfaces 10a and 10b of the irradiation object 10 arranged in the electron beam irradiation device 20.

[0005]

However, the cross-sectional shape of the irradiation object 10 is complicated, or
1 is required, the irradiation object 10
It is necessary to use two or more electron guns in addition to not only the upper part but also the lower part, so that a total of four or more electron guns are used, and there is a problem that the size of the electron beam irradiation device 20 becomes large and the cost becomes high. Was.

On the other hand, as shown in FIG. 8, an electron beam 2 is applied by using an electron gun 26 modified so as to be capable of irradiating from multiple directions.
Irradiation of the electron gun 4 from multiple directions surrounding the irradiation object 10 is conceivable in principle, but the internal structure of the electron gun 26 becomes very complicated and not only practical use is difficult but also lower surface irradiation is required. In such a case, even with such a multi-directional irradiation type electron gun, it is necessary to provide another one below the irradiation object 10, and a total of two units are required, and the electron beam irradiation device 20 becomes large. In addition, there is a problem that the cost increases.

[0007] The present invention has to have been made to solve the conventional problems, without increasing the number of electron guns, in the apparatus of compact and simple construction, the side surface or lower surface of the irradiated object with thickness An object is to enable irradiation.

[0008]

The present invention SUMMARY OF], in the electron beam irradiation apparatus for irradiating an electron beam to <br/> radiation having a thickness, at a position facing the side and below the irradiated object, the electronic At least one reflecting means having a substantially triangular cross section for reflecting lines is provided.
The above-mentioned problem is solved by arranging a pair and irradiating a required electron beam to a side surface and a lower surface of an irradiation object.

Further, the cooling means is built in the reflection means.

[0010] Also, it is provided with a means for adjusting the relative position of the front Kihan morphism means.

Further, the reflecting means includes a plurality of reflecting surfaces ,
A means for changing the angles of the plurality of reflecting surfaces is provided.

Generally, high-Z materials such as lead and tungsten are:
It is known as a material that reflects electron beams well. The present invention applies this characteristic to an electron beam irradiation technique, and irradiates the side surface and the lower surface of an irradiation object. That is, the electron beam emitted from the electron gun hits the surface of the reflective material, and a part thereof is reflected there. Then, part of the reflected electron beam hits the irradiated object. Thereby, the side surface and the lower surface of the irradiation object can be irradiated.

With respect to the irradiation object 10 having an inverted trapezoidal shape having an arrangement relationship as shown in FIG. 1, the irradiation object 10 has an upper surface 10u perpendicular to the traveling direction of the electron beam 24 irradiated from above. Is installed, the right side surface 10a in the vertical direction, and
Reflection blocks 30a and 30b having a substantially triangular cross section are disposed below each of the downward left side surfaces 10b inclined at about 60 ° with respect to the horizontal plane.
s with respect to the irradiation amount of the upper surface 10u when the angle θ of the s with respect to the horizontal plane is changed.
FIG. 2 shows the result of measuring the irradiation dose ratio of the solid line A (right side 1).
0a) and a broken line B (left side surface 10b).

In FIG. 1, the size of the irradiation object 10 is such that the width of the upper surface 10u is 30 mm, the thickness is 20 mm, and the inclination angle θ of the left downward side surface 10b with respect to the horizontal plane is approximately 60
°, and the width of the electron beam 24 is 100 mm. Again
The reflection blocks 30a, 30b have a lower surface 30l length of 30 mm, an interval between the tip ends thereof of 20 mm, and a distance of the lower surface 30l of the reflection blocks 30a, 30b from the lower surface 10l of the irradiation object 10 to 8 mm. They were arranged facing each other.

In FIG. 2, the horizontal axis is the tangent (tan) of the angle θ formed by the reflection surface 30s with respect to the horizontal plane, and tan θ = 0 at the left end is when the reflection blocks 30a and 30b do not exist.

From FIG. 2, each surface of the irradiation object has an optimum angle of the reflection surface, and particularly, tan θ =
It can be seen that near 0.5, an irradiation dose close to the upper surface 10u is obtained.

The present invention has been made based on such experimental results.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

According to the first embodiment of the present invention, as shown in FIG. 3, an irradiation object 10 arranged in an electron beam irradiation apparatus 20 is irradiated with an electron beam 24 from above by an electron gun 22. A pair of reflecting devices 4 obliquely below the irradiation object 10.
0a and 40b are provided.

As shown in detail in FIG. 4, a cooling pipe 44 is disposed on the back surface of the reflection block 42 constituting the reflection devices 40a and 40b to prevent deformation due to temperature rise caused by electron beam irradiation.

The reflection block 42 is provided with a position adjustment mechanism 46 for adjusting the position in the left and right direction (direction of arrow C) and an angle adjustment mechanism 48 for adjusting the angle in the direction of arrow D. The position and angle of the irradiation object 10 can be adjusted to an optimum position and angle according to the irradiation energy of the electron beam.

In the first embodiment, the reflecting surface is formed as a continuous concave surface. However, the reflecting surface may be formed as a convex surface or a single flat surface, or as shown in the second embodiment shown in FIG. Is divided into two planar reflectors 50a and 50b, and the two are connected by a hinge 52, and the position of the hinge 52 is changed in the direction of arrow E by a position adjusting mechanism 54, whereby the reflecting surface of the irradiation object 10 is changed. The shape may be changeable.

According to the second embodiment, the adaptability to the shape change of the irradiation object is particularly high.

The surface shape of the reflectors 50a and 50b is not limited to a plane, but may be a curved surface such as a concave surface or a convex surface.

In each of the above embodiments,
The cooling pipe 44 serves as the reflection block 42 and the reflection plates 50a,
0b, but the cooling means is not limited to this. For example, as in the third embodiment shown in FIG. 6, a cooling hole 60 is formed in the reflection block 42, and the cooling hole 60 is formed therein. You can also pass water. If the temperature rise is not a problem,
The cooling means may be omitted.

The reflection block 42 and the reflection plates 50a and 5a
The material of Ob is preferably lead or tungsten, but the material of the reflection means is not limited to this.

[0027]

According to the present invention, it is possible to irradiate the required electron beam to the side surface and the lower surface of the irradiation object by using a compact and simple device without increasing the number of electron guns. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an arrangement in an experiment by the inventors for explaining the principle of the present invention.

FIG. 2 is a diagram showing experimental results according to FIG. 1;

FIG. 3 is a cross-sectional view showing the overall configuration of the first embodiment of the present invention.

FIG. 4 is an enlarged sectional view showing a detailed configuration of the first embodiment.

FIG. 5 is a sectional view showing a configuration of a reflection device used in a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the configuration of a reflection device used in the third embodiment.

FIG. 7 is a cross-sectional view showing a configuration of a conventional electron beam irradiation apparatus for performing side irradiation.

FIG. 8 is a cross-sectional view showing a possible configuration of an electron beam irradiation apparatus for performing irradiation from multiple directions.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Irradiated object 10a, 10b ... Side surface 10l ... Lower surface 10u ... Upper surface 20 ... Electron beam irradiation device 22 ... Electron gun 24 ... Electron beam 30a, 30b, 42 ... Reflection block 40a, 40b ... Reflection device 44 ... Cooling pipe 46, 54 ... Position adjusting mechanism 48 ... Angle adjusting mechanism 50a, 50b ... Reflector 52 ... Hinge 60 ... Cooling hole

Claims (4)

(57) [Claims] 1. An electron beam irradiation apparatus for irradiating an irradiation object having a thickness with an electron beam, wherein the electron beam is reflected at a position facing a side and a lower side of the irradiation object .
An electron beam irradiating apparatus characterized in that at least one pair of reflecting means having a substantially triangular cross section is provided for irradiating a required electron beam to a side surface and a lower surface of an irradiation object. 2. An electron beam irradiation apparatus according to claim 1, wherein a cooling means is built in said reflection means. 3. The method of claim 1 or 2, before Kihan morphism means
An electron beam irradiation apparatus comprising means for adjusting a relative position . 4. An electron beam irradiation apparatus according to claim 1, wherein said reflecting means includes a plurality of reflecting surfaces, and means for changing an angle of said plurality of reflecting surfaces is provided.