JPH07119839B2 - Irradiation window - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an irradiation window for cooling a window foil with a water cooling bar provided on a window flange.

[0002]

2. Description of the Related Art When an electron beam is extracted from an electron beam generator to an irradiation area, the electron beam generator is in a vacuum state and the irradiation area is in the atmosphere or an inert gas atmosphere. A metal foil capable of transmitting electron beams is attached to keep the inside of the electron beam generating section in a vacuum state. 3 to 5 are configuration diagrams of an example of an irradiation window to which such a metal foil is attached, FIG. 3 is a front view seen from the irradiation region side, FIG. 4 is a sectional view taken along the line AA of FIG. FIG. 5 is a sectional view taken along line BB in FIG. A vacuum seal portion having an O-ring 3 is formed on the window flange 2 provided on the electron beam extracting portion and to which the metal foil, that is, the window foil 1 is attached, and the foil pressing plate 4 is fixed to the window flange 2 with the bolt 5. Thus, the window foil 1 is attached in close contact with the window flange 2 so as to be located outside the irradiation window.

When the electron beam passes through the window foil 1, a part of energy is lost and the window foil is heated. In order to prevent the window foil from being damaged by this heating, a large number of water cooling bars 6 are provided on the window flange 2. By flowing the cooling water through the refrigerant passage 7 formed inside the window flange 2,
The water cooling bar 6 is cooled. When the inside of the irradiation window and the inside of the irradiation window are evacuated, the window foil 1 comes into contact with the water cooling bars 6 and is cooled.

[0004]

As described above, when the window foil 1 is attached to the window flange 2 and a vacuum is applied, the window foil surface is stretched or slackened when the window foil is attached. As shown in FIG. 3, wrinkles 8 may occur. As shown in FIG. 5, the wrinkles 8 do not come into contact with the water cooling bars 6, and therefore wrinkles on the surface of the window foil lead to a reduction in the life of the window foil.

An object of the present invention is to provide an irradiation window that does not cause wrinkles on the window foil surface.

[0006]

According to the present invention, there is provided a water-cooling structure, a window flange mounted so that a window foil is located outside an irradiation window, and a window flange provided on the window flange and contacting the window foil. In the irradiation window provided with a water-cooling bar for cooling by cooling, the window foil contact end surface of the water-cooling bar is at a position retracted inward of the irradiation window from the window-foil mounting plane of the window flange. .

[0007]

[Function] The window foil is attached to the window flange so as to be located outside the irradiation window, and the window foil contacting end surface of the water cooling bar provided on the window flange is positioned inside the irradiation window from the window foil mounting plane of the window flange. Since it is retracted, the step difference between the contact end surface and the mounting plane absorbs the extension of the window foil during vacuuming and the tummy portion when the window foil is attached, so that no wrinkles occur on the window foil surface.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. 1 and 2 are sectional views of the irradiation window corresponding to FIGS. 4 and 5 described above, and the same reference numerals as those in FIGS. 4 and 5 denote the same or corresponding portions. A vacuum seal portion having an O-ring 3 is formed on the window flange 2 to which the window foil 1 is attached. By fixing the foil pressing plate 4 to the window flange 2 with bolts 5, the window foil 1 is placed outside the irradiation window. The window flange 2 is attached so as to be positioned so as to be positioned. A large number of water cooling bars 6 are provided on the window flange 2.
Is provided, and the end of the water-cooling bar on the irradiation area side, that is, the end face of the water-cooling bar contacting the window foil is located at a distance d inward from the plane of the window flange 2 where the window foil is attached. Thus, the water cooling bar 6 is provided on the window flange 2.

As described above, the surface of the window foil 1 in contact with the water-cooling bar 6 is lower than the mounting surface of the window foil, that is, the window foil irradiates the window-foil contact end surface of the water-cooling bar provided on the window flange. By retreating inward of the irradiation window from the window foil attachment plane of the window flange that is attached so as to be located outside the window, at this step portion,
The expansion of the window foil that occurs when the vacuum is evacuated, and the tarmi that occurs when the window foil is attached to the window flange 2 is absorbed, and wrinkles do not remain on the window foil surface when the vacuum is evacuated. I was able to get an irradiation window that would not let me.

[0010]

As described above, according to the present invention, the window foil contact surface of the water-cooling bar is simply lowered and retracted from the window-flange mounting plane of the window flange. It is possible to configure an irradiation window that does not cause wrinkles on the surface and can evenly contact the window foil with the water-cooling bars, and extend the life of the window foil.

[Brief description of drawings]

FIG. 1 is a cross-sectional view at a position parallel to a water cooling rail according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view at a position orthogonal to a water cooling rail.

FIG. 3 is a front view of a conventional irradiation window as viewed from the irradiation region side.

FIG. 4 is a cross-sectional view at a position parallel to the water cooling rail.

FIG. 5 is a cross-sectional view at a position orthogonal to the water cooling rail.

[Explanation of symbols]

 1 Window foil 2 Window flange 4 Foil pressing plate 6 Water cooling bar 7 Refrigerant passage 8 Wrinkle d Water cooling bar retreat distance

Claims (1)

[Claims] 1. A window flange having a water-cooled structure, the window flange being attached so that the window foil is located outside the irradiation window,
In an irradiation window provided with this window flange and a water-cooling bar for cooling by contacting the window foil, a window foil contact surface of the water-cooling bar is directed inward of the irradiation window from a plane of the window flange for mounting the window foil. Irradiation window characterized by being in a retracted position.