JPH0729800U - X-ray irradiation device - Google Patents

Abstract

(57) [Abstract] [Purpose] To simplify the cooling water piping equipment of the water cooling duct that covers the beam shutter and irradiation window. [Structure] An electron beam introduced into a scanning tube 1 from an electron beam generator is taken out into the atmosphere through an irradiation window 2. An electron absorption movable member 10 is provided below the irradiation window, and this member is configured by integrating a water cooling duct portion 11 that covers a flange portion of the irradiation window and a beam shutter portion 12, and cooling water for both portions is cooled. The passage 13 is continuous. When an X-ray is generated, the electron beam from the irradiation window passes through the opening 14 of the water cooling duct section and is incident on the X-ray target. Electrons scattered from the target toward the flange of the irradiation window are captured and absorbed by the water-cooled target. When the X-ray irradiator is started and stopped, the electron absorption movable member moves to the position shown by the alternate long and short dash line, and the beam shutter unit blocks the electron beam from entering the X-ray target.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an X-ray irradiation apparatus in which a beam shutter and a water cooling duct that covers a flange portion of an irradiation window are integrated to simplify a cooling water piping facility.

[0002]

[Prior art]

FIG. 3 is a sectional view showing an example of the scanning X-ray irradiation device. An electron beam from an electron beam generator having a thermionic emission filament and an accelerating tube is introduced into the scanning tube 1, and the electron beam is taken out into the atmosphere through an irradiation window 2 provided at the end of the scanning tube 1 and is directed to the X-ray target 3. At the same time, X-rays are being generated. The irradiation window 2 has a window foil 2 ₂ attached to a flange portion 1 ₁ at the end of the scanning tube 1 with a foil holding plate 2 ₁ , and seals the electron beam generator and the scanning tube 1 in a vacuum state. ing.

When the electron beam hits the X-ray target 3, scattered electrons are generated. When a part of the scattered electrons hits the flange portion of the irradiation window including the foil holding plate 2 ₁ in the irradiation window 2, the flange portion absorbs the energy of the scattered electrons and generates heat. Along with this, for example, the sealing function is lowered due to the difference in thermal expansion of the vacuum sealing mechanism member in the flange portion of the irradiation window 2, and the degree of vacuum in the scanning tube 1 is deteriorated. Therefore, a water cooling duct 4 covering the flange portion of the irradiation window 2 is provided so that scattered electrons hitting the flange portion are absorbed by the same duct. FIGS. 4 (a) Hano is a perspective view of the water cooling duct 4, passing a coolant in the coolant passage 4 ₁ of the duct, thereby preventing heat generation caused by the absorption of the scattered electrons.

When the operation of the X-ray irradiator is started and stopped (when the operation is started and stopped), the beam shutter 5 is moved from the position shown by the solid line in FIG. 3 to the position shown by the alternate long and short dash line. The electron beam is blocked from entering the target 3 so that X-rays are not generated. 4 (b) is bi - is a perspective view of Mushatta 5, Dobi - inside the Mushatta are passages 5 ₁ of the cooling water is formed, thereby preventing heat generation due to absorption of the electron beam.

[0005]

[Problems to be solved by the device]

 According to the present invention, as described above, the beam shutter 5 which is the electron beam absorbing member having the water cooling mechanism is activated and deactivated when the operation of the X-ray irradiation apparatus is started, for example, when the operation is started. In consideration of the fact that the electron beam temporarily blocks the electron beam for a short time until it rises to a predetermined beam amount and about 80% of the rated beam amount, both electron absorption and heat generation due to electron absorption are removed. The purpose of the present invention is to provide an X-ray irradiation device in which the beam shutter, which is a member having a water cooling mechanism, and the water cooling duct 4 are integrated to simplify the cooling water piping equipment.

[0006]

[Means for Solving the Problems]

 The present invention relates to an X-ray irradiation apparatus having a water-cooling duct that covers a flange portion of an irradiation window and a beam shutter that blocks incidence of an electron beam on an X-ray target, in which the water cooling duct and the beam shutter are inside. It is characterized in that the cooling water passages are continuous and integrated.

[0007]

[Action]

 Since the cooling water passages inside the water cooling duct and the beam shutter are continuous and are integrally formed, it is not necessary to provide a cooling water pipe to the water cooling duct and the beam shutter.

[0008]

【Example】

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a scanning X-ray irradiator, and FIG. 2 is a perspective view of an electron absorbing movable member having a water cooling duct section and a beam shutter section. The same reference numerals as those in FIGS. . The electron beam from the electron beam generator is introduced into the scanning tube 1, and the electron beam is taken out into the atmosphere through the irradiation window 2 provided at the end of the scanning tube 1 and is applied to the X-ray target 3 to generate the X-ray. The irradiation window 2 for transmitting the electron beam from the scanning tube 1 has a window foil 2 ₂ attached to a foil holding plate 2 ₁ on a flange portion 1 ₁ at the end of the scanning tube 1, and an electron beam generating portion and The inside of the scanning tube 1 is sealed in a vacuum state.

Below the irradiation window 2, an electron absorbing movable member 10 in which a water cooling duct and a beam shutter are integrated is provided. The movable member is composed of a water cooling duct portion 11 that covers the flange portion of the irradiation window 2 and a beam shutter portion 12 that blocks the incidence of an electron beam on the X-ray target 3, which are integrally connected. 10 ₁ is a common part of the water cooling duct part and the beam shutter part. The cooling water passage 13 formed inside the water cooling duct portion 11 and the beam shutter portion 12 in the electron absorbing movable member 10 is continuous, and accordingly, one set of cooling water is provided for both cooling water passages. Cooling water is supplied by piping.

When X-rays are generated, the electron-absorption movable member 10 is moved to the open position shown in FIG. The electron beam transmitted through the irradiation window 2 passes through the opening 14 of the water cooling duct portion 11 and is incident on the X-ray target 3. Electrons scattered from the target toward the flange portion of the irradiation window 2 are captured and absorbed by the water cooling duct portion 11.

When the operation of the X-ray irradiation apparatus is started and stopped, the electron absorption movable member 10 is moved to a closed position where the beam shutter 12 covers the X-ray target 3 and blocks the electron beam. In this case, as the electron beam enters the beam shutter section 12, scattered electrons are generated from the same and hit the flange section of the irradiation window 2, but the electron beam enters the beam shutter section in a short time. Since the incident amount is less than the rated value, the heat generation of the irradiation window is not a problem.

[0012]

[Effect of device]

 According to the present invention, as described above, the water cooling duct that covers the flange of the irradiation window and the beam shutter that shields the electron beam to the X-ray target are integrally connected, and the cooling water passage inside them is continuous. Since it is formed, the cooling water piping facility is simplified.

With the integration of the water cooling duct and the beam shutter, the electron beam passing air layer between the irradiation window and the X-ray target can be shortened, and the air layer is heated and the electron beam energy is reduced. The loss can be reduced, and the water cooling duct portion and a part of the beam shutter portion can be shared, so that the entire structure can be made compact.

[Brief description of drawings]

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

FIG. 2 is a perspective view of an electron absorption movable member in the example.

FIG. 3 is a sectional view of a conventional X-ray irradiation device.

FIG. 4 is a perspective view of a water cooling duct and a beam shutter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scan tube 2 Irradiation window 3 X-ray target 4 Water cooling duct 5 Beam shutter 10 Electron absorption movable member 11 Water cooling duct part 12 Beam shutter part 13 Cooling water passage

Claims (1)

[Scope of utility model registration request] 1. An X-ray irradiation apparatus having a water-cooling duct covering a flange portion of an irradiation window and a beam shutter for blocking an electron beam from entering an X-ray target, wherein the water-cooling duct and the beam shutter are inside. An X-ray irradiating device, characterized in that the cooling water passages are continuously formed as one body.