JPH0566300A - Radiation transmission window structure - Google Patents

Abstract

PURPOSE:To enable gas tight connection by holding a foil shaped radiation transmission window between a ring flange which is a part of a vacuum chamber, and a pusher ring, and by adhering with heat resistive organic adhesive. CONSTITUTION:On an upper surface of a flange 12 having a protrusion part 13, heat resistive organic adhesive 17 is painted. On that painted adhesive 17, a foil shaped radiation transmission window 18 made of an around 30mum thick beryllium, for example, is placed. Thereon, a pusher ring 14 having an indent part 16 is also placed, and then the adhesive 17 and the window 18 plate are holded, fastened and fixed between the flange 12 and the pusher ring 14, by plurality of bolts 15, 15 and so on. This composition is processed for predetermined time duration and at predetermined temperature to harden the adhesive 17 and to make the beryllium plate 18 contact gas-tightly to the flange. In this way, since the composition thereabove can be stably used within a temperature range upto 200 deg.C and the penetration window is tensioned by protrusion parts 13 and 16 as well as gas-tight jointing area increases via the adhesive 17, high vacuum condition can be attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation transmissive window structure, and more particularly to improvement of a hermetically bonded state of a foil-shaped radiation transmissive window.

[0002]

2. Description of the Related Art For example, in an X-ray tube, an X-ray spatial distribution measuring instrument, a radiation proportional counter, a neutron measuring tube, a detector of an X-ray spectroscope, or an X-ray lithography, a part of a vacuum container thereof is exposed to radiation. A window structure is used. This is disclosed, for example, in Japanese Utility Model Laid-Open No. 63-14357 and Japanese Patent Laid-Open No. 63-27.
3100 publication. Alternatively, it is disclosed in Japanese Patent Laid-Open No. 1-276550. Generally, this radiation transmitting window structure is formed by hermetically brazing a radiation transmitting window such as a beryllium thin plate to a thick flange that is a part of a vacuum container.

[0003]

In the conventional radiation transmitting window structure, a so-called "waxing" phenomenon in which beryllium forms a compound with silver or copper or other additive elements in the brazing material is likely to occur. .. Especially, copper easily reacts with helium. Therefore, the mechanical strength of the window plate may be extremely reduced particularly near the brazing portion. Therefore, since the thickness of the beryllium plate that can be used is 100 μm or more, it is difficult to use a radiation transmission window having a thickness that is less than that required recently, for example, 50 μm or less.

An object of the present invention is to solve the above problems and to provide a radiation transmitting window structure having a highly reliable airtight bonding structure by using a relatively thin radiation transmitting window.

[0005]

According to the present invention, a foil-shaped radiation transmitting window is sandwiched between a ring-shaped flange forming a part of a vacuum container and a pressing ring, and a flange is made of a heat-resistant organic adhesive. It is a radiation transmitting window structure that is airtightly bonded.

[0006]

According to the present invention, the foil-like radiation transmitting window is not corroded by the adhesive, and therefore the mechanical strength of the window material is not deteriorated and the pressure difference between the inside and outside of the vacuum container can be sufficiently endured. Also, the window material can be made sufficiently thinner than before.

[0007]

Embodiments will be described below with reference to the drawings. The same parts are denoted by the same reference numerals. In the embodiment shown in FIGS. 1 and 2, a thick-walled ring flange 12 made of, for example, stainless steel is hermetically joined to a part of a vacuum container 11. The flange 12 has a smooth curved convex portion
13 are integrally formed. A similar pressing ring 14 can be fixed on the flange 12 by a plurality of bolts 15, 15. This holding ring 14 has
Smooth curved recesses 16 are formed to fit the flange protrusions 13 so that they can fit together.

Therefore, to explain according to the assembling procedure, first, the heat-resistant organic adhesive 17 is applied to the upper surface of the flange 12. Next, a beryllium foil radiation transmission window 18 made of beryllium having a thickness of 30 micrometers is placed on the adhesive 17. Then, the pressing ring 14 is placed thereon, and the adhesive and the window plate are clamped and fixed between the flange and the pressing ring by a plurality of bolts 15, 15, .... These are treated for a predetermined time at a predetermined temperature to cure the adhesive,
Airtightly join a beryllium plate to the flange.

The radiation transmitting window structure thus completed can be stably used in a temperature range up to about 200.degree. In addition, since the foil-shaped radiation transmitting window is tensioned by the convex portion and the concave portion formed on the flange and the pressing ring, and the airtight bonding area through the adhesive increases, a more reliable airtight window structure can be obtained. Be done.

The embodiment shown in FIG. 3 has a foil-like radiation transmission window 18
An adhesive agent is applied to both sides of the above and airtightly joined.
Steps 12a and 14a are formed on the inner peripheral walls of the flange 12 and the pressing ring 14 facing the window plate 18, so that the adhesive 17 does not protrude into the radiation transmission path. As a result, the airtight joint is more complete, the radiation does not hit the adhesive, and there is no risk of deterioration of the adhesive or generation of impure radiation from the adhesive.

The flange and the pressing ring are not limited to stainless steel, and other materials having high mechanical strength, good contact with the adhesive, and not corroded by the adhesive can be used. In addition, the radiation transmission window is a beryllium plate (thickness is 1
Not limited to 0 to 100 micrometers), for example, aluminum foil (thickness is 30 to 100 micrometers), resin film such as heat-resistant polyimide film (thickness is 25 to 50 micrometers), etc. , And a material having good vacuum tightness can be used. Furthermore, as the adhesive, a one-component or two-component epoxy structure adhesive or a heat-resistant vacuum-tight organic adhesive such as a one-component thermosetting adhesive can be used.

[0012]

As described above, according to the present invention,
The radiation transmitting window is not corroded by the adhesive, so that the mechanical strength of the window material is not deteriorated and the pressure difference between the inside and the outside of the vacuum container can be sufficiently endured. Further, the window member can be made sufficiently thinner than before, and a radiation transmitting window structure having excellent radiation transmitting property and vacuum tightness can be obtained.

[Brief description of drawings]

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

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is an enlarged view of a main part showing another embodiment of the present invention.

[Explanation of symbols]

11 ... Vacuum container, 12 ... Flange, 14 ... Pressing ring, 17 ...
Adhesive, 18 ... Radiation transparent window.

Claims (1)

[Claims] 1. A radiation transmission window structure comprising a foil-shaped radiation transmission window hermetically joined to a ring-shaped flange provided in a part of a vacuum container, wherein the foil radiation transmission window is pressed against the ring-shaped flange. A radiation transmitting window structure, which is sandwiched between a ring and airtightly bonded to the ring-shaped flange with a heat-resistant organic adhesive.