JPH047557Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to an X-ray tube suitable for measuring X-ray absorption edge microstructures in the soft X-ray region.

B. Conventional technology There are two types of X-ray tubes: closed type and open type. open type x
In order to make it possible to replace the cathode filament, the wire tube is designed so that the tube can be opened and the cathode section taken out, and a vacuum pump is installed to evacuate the tube before use.

When the above-mentioned open type X-ray tube is used as an X-ray source for X-ray spectrometry in the soft X-ray region, the tungsten of the filament is deposited on the target surface, and due to the X-ray absorption effect of this tungsten,
There was a problem that the X-ray source brightness decreased after long-term use.

C. Problems to be Solved by the Invention The present invention attempts to solve the above-mentioned problem of the reduction in source brightness of the X-ray source used for measurements in the soft X-ray region.

D. Means for solving the problem Of the body, cathode filament, and target that make up the X-ray tube, the body is directly connected to the analyzer body, and the cathode filament and target are connected to this body, respectively. It is attached removably and has an X-ray extraction window on the analyzer main body side, a shutter with an opening on which an X-ray transparent film is slidably stretched on the window surface, and a vacuum in the opening on the other side of the body. An X-ray analyzer in a vacuum region connected to a pump is provided.

E. Function The X-ray tube can be disassembled into three parts: target section, body section, and filament section, and the vacuum pump and X-ray spectrometer are connected to the body section. You can remove only the filament section or only the target section without removing the X-ray tube from the X-ray spectrometer, and you can replace the filament and wash the target at any time, making it possible to wash the target section. A decrease in source brightness is prevented.

F. Example The figure shows an example of the present invention. 1 is a cathode filament part, 2 is a target part, and 3 is a body part.
The body part 3 has a cylindrical shape with both ends open, and the cathode filament part 1 is connected to one end, and the target part 2 is connected to the other end, and an X-ray tube is constructed by combining the three parts. 1 and the target section 2 are each removably connected to the body section 3 by means of fastening bolts. The body 3 is provided with an X-ray extraction window 4 on one side and an exhaust port 5 on the other side.
An exhaust pump (not shown) is connected to the tube, and the inside of the X-ray tube is evacuated to 10 ^-6 to ^{10 -7} toor. A shutter plate 6 is provided on the outside of the X-ray extraction window 4 in sliding contact with the body 3, and this shutter plate is connected to an X-ray spectrometer connection flange 7 formed around the X-ray extraction window 4 of the body 3. It is attached to the tip of an operating rod 8 that airtightly penetrates the side surface of the body 3, and by moving the operating rod 8 left and right in the figure, it slides on the side surface of the body 3. A through hole 6h is bored in the shutter plate 6, and an X-ray transparent film F is placed over the through hole 6h.
is set up. 30 is the shutter plate 6 and the body 3
This is an O-ring that maintains an airtight seal with the side surface.

An X-ray spectrometer 9 is connected to the X-ray spectrometer connection flange 7 on the body 3, and the X-ray spectrometer 9 is connected to an exhaust system to prevent absorption of X-rays in the soft X-ray region by the atmosphere. There is. Both the X-ray tube and the X-ray spectrometer are evacuated, but the degree of vacuum required for both is different.
Since the inside of the X-ray tube requires a high vacuum, the X-ray tube and the X-ray spectrometer 9 cannot communicate with each other in the internal space. It is arranged so that it overlaps with the X-ray extraction window 4 of , and the X-rays are extracted through the X-ray transparent film F. The inside of the X-ray spectrometer 9 may become atmospheric pressure due to sample exchange, etc., but in this case, operate the shutter plate 6 in advance to open the through hole 6h into the X-ray extraction window 4.
Remove it from the window and cover the window with the shutter board 6.
By doing so, the X-ray transparent film F will not be subjected to a large pressure difference such as atmospheric pressure on one side and vacuum on the other side, so it can be made thinner.
Conventionally, Be plates with a thickness of about 300 μm were used for the X-ray extraction window of X-ray tubes, which resulted in a large absorption loss of X-rays, but with the above-mentioned shutter configuration, the X-ray transparent film is sufficient. It can be made thinner and X-ray loss is reduced.

In the target section 2, 21 is a target body, and 22 is a cooling water circulation space. When cleaning the surface of the target 21, remove only the target section 2 from the body section 3 while keeping the exhaust pump, X-ray spectrometer 9, and filament section 1 connected to the body section 3, and perform target cleaning. It can be carried out. Similarly, when replacing the filament, only the cathode filament part 1 needs to be removed from the body part 3.

Effects As described above, in this invention, the cathode filament part and the target part of the X-ray tube are removably connected via the intermediate body part, and the exhaust system and the X-ray spectrometer are connected to the body part. To clean a target by removing only a target part from an X-ray tube without having to disassemble the entire structure of the X-ray spectrometer in an X-ray spectrometer consisting of a tube, an exhaust system, and an X-ray spectrometer. This makes it possible to easily recover from a decrease in the brightness of the X-ray source due to filament deposits adhering to the target, and to maintain the X-ray tube in good condition at all times.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional side view of an X-ray tube according to an embodiment of the present invention.

Claims (1)

[Scope of utility model registration request] Of the body, cathode filament, and target that make up the X-ray tube, the body is directly connected to the analyzer body, and the cathode filament and target are removably attached to the body. , an X-ray extraction window is provided on the analyzer main body side, a shutter having an opening with an X-ray transparent film slidably stretched over the window surface is provided, and a vacuum pump is connected to the opening on the other side of the body. Vacuum area X-ray analyzer.