JPH0754880Y2 - Electron beam irradiation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electron beam irradiation apparatus for irradiating an object to be processed with a curtain-shaped electron beam.

[Conventional technology]

FIG. 3 is a schematic sectional view of a conventional electron beam irradiation apparatus in the horizontal direction. The electron beam irradiation device includes a power supply unit 10, an electron beam generation unit 20, and an irradiation chamber 30.

The electron beam generator 20 includes a terminal 21 that generates an electron beam,
Electron accelerator tube 22 that accelerates an electron beam in a vacuum space (acceleration space)
And an insulating bushing 23 for attaching the terminal 21 to the electron accelerator tube 22. Further, the inside of the electron acceleration tube 22 is kept in vacuum by a diffusion pump or the like not shown.

The power supply unit 10 includes a heating power supply for heating a filament 25, which is an electron source stored in the terminal 21, and a filament.
It includes a DC high-voltage power supply for applying a high voltage between 25 and a grid (not shown) of the terminal 21. It is desirable that these power supply devices be formed in a round shape with no corners in order to prevent discharge. However, since it is difficult to form the power supply device into a round circular shape, these devices are housed in the Faraday cage 2 which is a round container in order to prevent discharge.

The center conductor 50 is electrically connected to the grid of the terminal 21 (not shown) and supplies a high DC voltage to the grid. The center conductor 50 is formed in a cylindrical shape, and the conductors 3, 3 connected to the filament 25 are disposed inside the center conductor 50 via an insulator 4.

With the above configuration, the filament 25
When electric power is supplied to, the thermoelectrons are released from the filament 25. In this state, the filament 25
When a voltage of several hundred volts is applied between the grid and the grid, the thermoelectrons are extracted as a curtain-shaped electron beam and irradiated on the object to be processed.

[Problems to be solved by the device]

By the way, the center conductor 50 is screwed to the insulating bushing 23 mainly through a fixing tool, and in order to prevent the electric discharge between the conductive wires 3 and 3 and other parts, the conductive wire is entirely provided from the insulating bushing 23 to the Faraday cage 2. Covers 3,3. Further, since the screw or the like is exposed at the end portion of the center conductor 50, the tip end portion of the center conductor 50 has a third position.
As shown in the figure, it is inserted even inside the Faraday cage 2.

Therefore, when the Faraday cage 2 is taken out by sliding in the direction X (sliding direction) perpendicular to the central axis direction of the center conductor 50, the center conductor 50 must also be removed. However, since the center conductor 50 is not only electrically connected but also has a gas seal, it is not easy to attach and detach it. Therefore, in the conventional electron beam irradiation apparatus, when it is necessary to take out the Faraday cage 2 in the X direction for inspection and repair of the power supply unit 10, it takes time and labor, and quick inspection and repair cannot be performed. There was a problem.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electron beam irradiation apparatus capable of easily attaching and detaching a Faraday cage.

[Means for Solving the Problems]

The present invention for achieving the above object, in an electron beam irradiation apparatus for controlling a thermoelectron emitted from an electron source by supplying a DC voltage to a grid, a conductor for supplying a DC voltage to the grid, It is characterized by being divided into two or more portions in the longitudinal direction and screwing the divided portions.

[Action]

According to the present invention, since the respective portions of the divided conductors are screwed with each other according to the above configuration, the lengthwise dimension of the conductor can be changed by adjusting the screwed state.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a schematic sectional view of a center conductor of an electron beam irradiation apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic sectional view of the electron beam irradiation apparatus in a vertical direction.

The terminal 21 includes a filament (for example, a linear cathode) 25 that is an electron source, and a gun structure that supports the filament 25.
26, a case 27 that houses the gun structure 26, and a grid 28 that controls the generated thermoelectrons.

The irradiation chamber 30 is provided with a transport mechanism for the object to be processed, and has a space for irradiating the object A with an electron beam.

The irradiation window section 40 includes a foil film-shaped window foil 41, and a window frame structure 42 for attaching the window foil 41 to the lower portion of the electron beam generation section 20, and the irradiation window section 40 of the electron beam generation section 20. It separates the vacuum atmosphere from the gas atmosphere of the irradiation chamber 30 and is also an outlet for taking out an electron beam. Incidentally, in the present embodiment, those having the same functions as the conventional ones are designated by the same reference numerals, and the detailed description thereof will be omitted.

The power supply unit 10 of the electron beam irradiation apparatus includes a heating power supply for heating the filament 25 and a DC high voltage power supply for applying a voltage of several hundreds of volts between the filament 25 and the grid 28.

Since the shapes of the internal devices of the heating power source and the DC high-voltage power source are generally uneven, it is easy to induce discharge. For this reason, the entire power supply device is housed in a circular container.
This container is a Faraday cage 2, which is formed by bending an aluminum plate having a thickness of about 1 mm.

A center conductor 1 (conductor) and two conductors 3 and 3 are passed between the Faraday cage 2 and the insulating bushing 23. The two conductors 3 and 3 are used for heating the filament 25 by a heating power source. It supplies the electric power of. In addition, the center conductor 1 is a filament 25 by a DC high voltage power source.
And a high DC voltage between the grid 28 and the grid 28. In addition, between the conductors 3,3 and between the center conductor 1 and the conductors 3,3
Although there is a potential difference of several tens of volts, the conductors 3, 3 and the center conductor 1 are both biased to an acceleration voltage of 200 KV. Due to this high voltage, the center conductor 1 and the conductors 3 and 3 easily induce discharge.

The center conductor 1 is formed by forming aluminum into a cylindrical shape, and the conductor 3 is housed therein. This is a conductor
This is to prevent electric discharge that occurs because 3, 3 are thin round wires. The insulator 4 is used to prevent contact between the conductor 3 and the center conductor 1.

Insulating gas is enclosed in the power supply unit 10 in order to prevent unnecessary discharge and the like due to high voltage. Insulation bushing 23
Is for partitioning the insulating gas atmosphere in the power source section 10 and the vacuum atmosphere in the electron acceleration tube 22 and supporting the terminal 21 in the hollow of the electron acceleration tube 22.

The center conductor 1 in the present embodiment has an inner conductor 1a and a cover conductor 1b as shown in FIG.
And a slide conductor 1c. There is a male screw on the outside of the inner conductor 1a
A female screw that is screwed into the male screw of the inner conductor 1a is formed inside the 1b and the slide conductor 1c.

The cover conductor 1b is integrated with the slide conductor 1c and covers the surface of the sharp male screw of the inner conductor 1a to prevent discharge by the male screw of the inner conductor 1a. During operation of the device, the cover conductor 1b is fixed to the inner conductor 1a and the cover conductor 1b cannot be moved.

With the above configuration, in the electron beam irradiation apparatus of this embodiment, by rotating the slide conductor 1c, the entire length of the center conductor 1 is expanded and contracted, and the tip portion of the center conductor 1 (tip portion of the slide conductor 1c) is expanded. Can be easily put in and taken out of the Faraday cage 2. Therefore, when attaching or detaching the Faraday cage 2,
It is not necessary to attach / detach the center conductor 1 together. That is, when the Faraday cage 2 is removed, the slide conductor 1c is rotated to remove the first
Since the tip of the slide conductor 1c can be pulled out to the upper part of the Faraday cage 2 as shown by the one-dot chain line in the figure, even when the Faraday cage 2 is slid in the direction perpendicular to the central axis direction of the center conductor 1 and removed, It is possible to easily remove only the Faraday cage 2 without removing the center conductor 1.

In the above embodiment, the center conductor is 3
Although the case where the conductor is divided into two is described, the present invention is not limited to this, and the center conductor may be divided into two or four.

[Effect of device]

As described above, according to the present invention, since the center conductor is divided into the expandable and retractable structure, the tip end of the center conductor can be easily put in and taken out from the Faraday cage. In this case, the Faraday cage can be easily attached and detached, and the electron beam irradiation apparatus that can perform such inspection and repair quickly can be provided.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a center conductor of an electron beam irradiation apparatus according to an embodiment of the present invention, FIG. 2 is a schematic sectional view of the electron beam irradiation apparatus in a vertical direction, and FIG. 3 is a conventional electron beam irradiation apparatus. It is a schematic sectional drawing in the horizontal direction. 1 ... Center conductor, 1a ... Inner conductor, 1b ... Cover conductor, 1c ... Slide conductor, 2 ... Faraday cage, 3 ... Conductor, 4 ... Insulator, 10 ... Power supply section, 20 ... Electron beam generator, 21 ... Terminal, 22 ... Electron accelerator tube, 23 ... Insulation bushing, 28 ...
… Grid, 30… Irradiation room, 40… Irradiation window, A… Object to be processed.

Claims (1)

[Scope of utility model registration request] 1. An electron beam irradiation device for controlling thermoelectrons emitted from an electron source by supplying a direct current voltage to a grid, wherein a conductor for supplying a direct current voltage to the grid has two or more portions in the longitudinal direction. An electron beam irradiation apparatus, characterized in that the electron beam irradiation apparatus is divided into two parts, and the divided parts are screwed together.