JPH088480Y2 - Conveyor for electron beam irradiation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a modified structure of a transfer conveyor in a non-scanning electron beam irradiation apparatus.

The electron beam irradiation device generates and accelerates an electron beam in a vacuum,
This is taken out into the atmospheric pressure and irradiated to the object to be processed in an inert gas atmosphere.

Its purpose is diverse, such as accelerating polymer polymerization reaction.

It can be used, for example, for cross-linking of electric wire coating, curing of coating film, sterilization, etc.

There are a scanning type that scans the electron beam in the horizontal direction and a non-scanning type that does not scan the beam. The non-scanning type has an acceleration energy of 300 kV or less.

The present invention relates to a modification of a transfer conveyor in a non-scanning type electron beam irradiation apparatus.

(B) Conventional Technology An outline of a non-scanning electron beam irradiation apparatus according to a conventional example will be described with reference to FIG.

The cathode filament section 2 is provided in the vacuum of the laterally-oriented cylindrical acceleration chamber 1. The upper half of this is covered with the cathode shield 3. The bottom of the acceleration chamber 1 is the irradiation window 4
It has become. The window foil 5 is stretched here.

These mechanisms are mounted on the central upper portion of the rectangular parallelepiped casing 6.

The case 6 has a series of conveyors 31 for carrying the objects to be processed.
Installed inside. This is guided by rollers 32, 32, ....

There is an inert gas outlet 33 for blowing nitrogen gas or the like into the space in which the object is to be treated. Further, an exhaust port 34 for removing the inert gas and air is provided.

Several X-ray shields 35 are provided in the housing 6.

The conveyor shown in FIG. 3 is used when processing a continuous and flexible web or the like.

Since the web can bend along the curvature of the conveyor, it can be conveniently transported on the series conveyor 31.

The conveyor shown in FIG. 4 has a vertical step. This is intended for a non-continuous plate-shaped object to be processed. Since it is not a continuous body, there may be a bending point in this way.

 There are two requirements for the conveyor.

One is that there is no amount of trapped air from the outside. The presence of oxygen significantly impairs the effect of electron beam irradiation. In addition, harmful ozone is generated.

In order to reduce carry-in air, the space through which the conveyor passes is narrowly divided by an X-ray shielding plate 35 or the like. Moreover, the inert gas is forcedly blown.

More important than that is to prevent secondary X-rays from leaking to the outside. Since the electron beam hits the object to be processed, strong secondary X-rays are generated. It goes straight, but it also reflects and scatters.

The whole body is surrounded by a housing 6 so that it does not leak outside. The conveyor outlet and inlet are open for the passage of the material to be processed.

Therefore, the path of the conveyor is bent and a number of X-ray shielding plates are placed to prevent the secondary X-rays from being reflected directly or once and going out.

Since these use a series of conveyors, the conveyor structure is simple. Further, there is an advantage that it is not necessary to transfer the object to be processed.

(C) Problems to be solved by the device Since the conventional conveyor is a series of conveyors,
The shape is folded up and down. The object to be processed passes through here. For this reason, the gap between the conveyor and the slit of the X-ray shield or the wall of the housing tends to be wide.

If the distance between the conveyor and other members is wide, the amount of air carried in from the outside increases. Then, nitrogen gas is needed to prevent this and lower the oxygen concentration.

Moreover, it is difficult to completely block X-rays in the case shown in FIG. There is a fear that X-rays may leak.

(D) Purpose One of the purposes of the present invention is to further reduce the oxygen concentration. This is to reduce the amount of trapped air.

It is another object of the present invention to make X-ray shielding more complete.

(E) Structure Auxiliary conveyors are provided on both sides of the conventional conveyor.
The feature of the present invention is that three conveyors are used.

A conventional series conveyor will be called a main conveyor.
The main conveyor and the auxiliary conveyor are connected in a substantially sealed shield box.

Therefore, it can be used for the purpose of X-ray shielding and reduction of oxygen concentration.

FIG. 1 is an overall configuration diagram of the non-scanning electron beam irradiation apparatus of the present invention. FIG. 2 is a partially longitudinal perspective view of a connecting portion between the auxiliary conveyor and the main conveyor.

The central part is the same as the conventional one. It may be that shown in FIG. 3 or that shown in FIG.

 Here, the one shown in FIG. 4 is taken as an example.

At the center of the laterally cylindrical acceleration chamber 1 is the cathode filament section 2. This produces thermoelectrons. It is a filament that extends laterally.

A cathode shield 3 surrounds the filament portion 2. This prevents corona discharge from occurring with the acceleration chamber wall. The thermoelectrons emitted from the filament unit 2 are accelerated downward. The irradiation window 4 is located below. here,
A window foil 5 made of Ti, Al or the like is stretched.

The top of the irradiation window 4 is vacuum, and the bottom is atmospheric pressure. Atmospheric pressure, but must not contain oxygen. Therefore, nitrogen gas, inert gas, or the like is blown from the inert gas blowing port 33 on the side of the irradiation window 4, which fills the inside of the housing 6. Excessive inert gas is exhausted from the exhaust port 34.

Although the main conveyor 31 is a series of conveyors, it is guided by rollers 32 and draws a locus of movement that is vertically bent.

 Conventionally, the end 37 of the main conveyor 31 was exposed.

However, in the present invention, the auxiliary conveyor 8 is further connected to the end 37 of the main conveyor 31.

 The connection portion is surrounded by the shielding box body 7.

The shielding box body 7 has two functions of preventing the trapping of air and the leakage of X-rays.

First, the shielding box body 7 is a substantially rectangular parallelepiped space and has its own exhaust port 9. This is done by blowing in the air that comes in with the irradiated object and eliminating it.

The auxiliary conveyor is a flat belt conveyor and can be bent freely. The conveyor bends from top to bottom, but brush the bottom surface of the upper conveyor and the top and bottom surfaces of the lower conveyor.
10 rubs. This prevents the movement of air and gas accompanying the conveyor.

The shielding box body 7 includes a horizontal bottom plate 11, a top plate 12, a front partition plate 13,
The side plate 14, the middle plate 15, the rear partition plate 16 and the like.

Rear partition plate 16, front partition plate to pass the upper piece of the conveyor
13 is separated from the upper plate 12. The smaller the distance between the auxiliary conveyor and the upper plate 12, the more the amount of air taken in can be reduced.

In the present invention, the distance between the auxiliary conveyor 8 and the upper plate 12 can be 20 mm or less. This is the case when the object to be processed is a plastic plate with a thickness of several mm.

Thus, the reason why the distance can be reduced is that the auxiliary conveyor moves almost horizontally and does not bend.

In addition to the function of supporting the conveyor 8, the middle plate 15 makes the movement of gas inside the shielding box 7 inactive, and also guides the moist air from the outside to the exhaust port 9 for easy removal. There is.

 More specifically, the function of the middle plate 15 is as follows.

Limit the space above the belt to a small size (for example, 20 mm or less),
It is to reduce the carry-in air and to discharge the carry-in air by creating a fluid flow as shown by the arrow in the figure.

The lower piece of the auxiliary conveyor 8 passes through the slit 17 of the rear partition plate 16. Since there is a brush 10 here, almost no gas can pass through.

The front end of the auxiliary conveyor 8 is supported by the small roller 18.

On the other hand, the main conveyor 31 is, for example, a stainless mesh conveyor, and the end portion 37 is supported by the large roller 19.

The object to be processed is transferred from the auxiliary conveyor 8 to the main conveyor 31.

Front partition plate at the boundary between the auxiliary conveyor 8 and the main conveyor 31
13 is a lead plate, or it is good to stick a lead plate. This is to prevent the secondary X-rays from leaking from here.

(F) Action The object to be processed is conveyed by three conveyors such as the auxiliary conveyor 8, the main conveyor 31, and the auxiliary conveyor 8.

The clogging of air is once blocked by the shielding box 7 of the auxiliary conveyor 8. The air is removed by the exhaust port 9. After this, the conventional case 6 is entered. Again, the exhaust air is removed from the exhaust port 34. Nitrogen gas is supplied from the outlet 33 to the internal space of the housing.

The secondary X-rays are also removed by some X-ray shielding plates 35 in the housing 6. Some X-rays are reflected along the aperture.

 Once reflected, the X-rays become significantly weaker.

In the conventional case and conveyor structure, the weak X-rays that were reflected twice were likely to be emitted to the outside.

However, in the present invention, it has to be reflected again to pass through the shield box 17 of the auxiliary conveyor. Therefore, X-rays cannot be emitted to the outside unless they are reflected three times.

This does not mean that everything that is reflected three times goes out. It means that only the special beam reflected three times with proper incident and reflection angles goes out.

What is feared to leak to the outside after being reflected twice is that it will not go outside unless it is reflected at least three times. X-ray leakage can be prevented more completely.

(G) Effect The concentration of oxygen carried inside the housing can be significantly reduced. The air entering the object to be processed from the outside is reduced when passing through the narrow gap, and is discharged at the part of the auxiliary conveyor.

Therefore, conversely, it is possible to reduce the amount of nitrogen gas blown in.

Also, the secondary X-rays will not go out unless they are reflected three times. Therefore, the leakage of X-rays to the outside is extremely small.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a non-scanning electron beam irradiation apparatus of the present invention. FIG. 2 is a partial vertical perspective view of a connecting portion between the auxiliary conveyor and the main conveyor. FIG. 3 is an overall configuration diagram showing an example of a non-scanning electron beam irradiation apparatus. FIG. 4 is an overall configuration diagram showing another example of the non-scanning electron beam irradiation apparatus. 1 ... Acceleration chamber 2 ... Cathode filament part 3 ... Cathode shield 4 ... Irradiation window 5 ... Window foil 6 ... Housing 7 ... Shielding box 8 ... Auxiliary conveyor 9 ... Exhaust port 10 ... Brush 11 …… Bottom plate 12 …… Top plate 13 …… Front partition plate 14 …… Side plate 15 …… Middle plate 16 …… Rear partition plate 17 …… Slit 18 …… Small roller 19 …… Large roller 31 …… Main ( Series) Conveyor 32 …… Roller 33 …… Inert gas outlet 34 …… Exhaust port 35,36 …… X-ray shield 37 …… End of main conveyor

Claims (1)

[Scope of utility model registration request] 1. An electron beam irradiation apparatus for generating and accelerating an electron beam in a vacuum and ejecting the electron beam through a window foil 5 of an irradiation window 4 to irradiate an object to be processed in an atmosphere of an inert gas atmosphere, The main conveyor 31 is a conveyor that conveys the object to be processed from outside to just below the irradiation window 4 and further takes it out, and two auxiliary conveyors 8 provided on both sides of the main conveyor 31.
8, the main conveyor 31 has a proper number of X-ray shielding plates 35 along the locus of vertically bending in the rectangular parallelepiped housing 6.
Orbiting through 36 narrow openings, the main conveyor 31
The connection between the auxiliary conveyor 8 and the auxiliary conveyor 8 is surrounded by a shielding box body 7 having an intermediate plate 15 for supporting the auxiliary conveyor 8 therein, and the shielding box body 7 is an exhaust port for forcibly exhausting the gas inside. An electron beam irradiating device conveyor comprising a front partition plate 13 for partitioning the main conveyor 31 and the auxiliary conveyor 8 of the shield box 7 from lead or a lead plate attached.