JP2023019528A - High-frequency input coupler - Google Patents

Abstract

To provide a high-frequency input coupler that can prevent a gap from being generated between a dielectric substrate and a high-frequency window structure.SOLUTION: The high-frequency input coupler is installed between a waveguide and an acceleration cavity and inputs a high-frequency wave from the waveguide to the acceleration cavity. The high-frequency input coupler includes an inner conductor, an outer conductor provided around the periphery of the inner conductor, a high-frequency transmission window structure having a high-frequency transmission window, and a dielectric substrate provided on a high-frequency input side of the high-frequency transmission window. The dielectric substrate is fixed to the high-frequency transmission window structure by brazing.SELECTED DRAWING: Figure 1

Description

Embodiments of the present invention relate to high frequency input couplers.

A high-frequency input coupler is used in a charged particle (electron, ion, proton) accelerator when injecting a high-frequency (microwave) emitted from a high-frequency amplifier such as a klystron into an acceleration cavity.

When a high frequency (microwave) is injected into an accelerating cavity, a high frequency input coupler (coupler) having a structure capable of providing good coupling to the accelerating cavity is required. A high-frequency input coupler is mainly composed of a high-frequency transmission window structure having a high-frequency transmission window, an outer conductor, and an inner conductor (antenna), and the outer conductor and the inner conductor form a coaxial structure.
Such a high frequency input coupler may have a dielectric substrate disposed on the high frequency input side of the high frequency transparent window assembly. A waveguide having a coaxial waveguide conversion structure for converting a high frequency transmitted from a high frequency source is attached to the high frequency transmission window structure on the entrance side of the high frequency.

JP-A-02-295023

Conventionally, the dielectric substrate consists of the waveguide-side end of the inner sleeve (inner conductor) of the high-frequency transmission window structure, and the waveguide-side inner conductor whose one end is fixed to the coaxial waveguide converter (doorknob) with bolts. It is fixed so as to be sandwiched between the other end of the However, if the bolted inner conductor on the waveguide side and the inner sleeve (inner conductor) are sandwiched and fixed, the bolt may become loose due to, for example, long-term use. When a high frequency is input, a gap is generated, and discharge occurs, which may hinder operation. Also, even if the bolt is not loosened, a similar problem may occur when a gap is generated between the dielectric substrate and the dielectric substrate at the portion where the dielectric substrate is sandwiched.

An object of the present embodiment is to provide a high-frequency input coupler that can prevent a gap from forming between a dielectric substrate and a high-frequency window structure.

One embodiment is a high-frequency input coupler provided between a waveguide and an accelerating cavity for inputting high-frequency waves from the waveguide to the accelerating cavity, comprising: an inner conductor; A conductor, a high frequency transmission window structure having a high frequency transmission window, and a dielectric substrate provided on the high frequency input side of the high frequency transmission window, the dielectric substrate being fixed to the high frequency transmission window structure by brazing. A high frequency input coupler.

FIG. 1 is a vertical cross-sectional view showing a state in which a high-frequency input coupler according to the first embodiment is provided between a waveguide and an acceleration cavity. FIG. 2 is a vertical cross-sectional view showing a state in which a high-frequency input coupler according to the second embodiment is provided between a waveguide and an acceleration cavity.

An embodiment will be described in detail below with reference to the drawings. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual embodiment, but this is only an example, and the embodiment of the present invention. It does not limit interpretation. In addition, in this specification and each figure, the same reference numerals are given to components that exhibit the same or similar functions as those described above with respect to the previous figures, and redundant detailed description may be omitted as appropriate. .

A first embodiment will be described with reference to FIG.
As shown in FIG. 1, a high-frequency input coupler 1 according to the first embodiment is provided between a waveguide 3 and an acceleration cavity 5, and inputs high-frequency waves from the waveguide 3 to the acceleration cavity 5. is.
This high-frequency input coupler 1 includes an inner conductor 7, an outer conductor 9 provided on the outer periphery of the inner conductor 7, a high-frequency transmission window structure 13 having a high-frequency transmission window 11, and a high-frequency transmission window structure 13 provided on the high-frequency input side of the high-frequency transmission window 11. and a dielectric substrate 14 .
The waveguide 3 is mainly assembled by welding. A coaxial waveguide converter 15 called a doorknob is connected to the waveguide 3 by welding.

The inner conductor 7 is provided to pass through the high-frequency transmission window structure 13, and the waveguide-side inner conductor 8 continuous with the inner conductor 7 is provided in the coaxial waveguide conversion section 15 of the waveguide 3. there is One end 8 a of the waveguide-side inner conductor 8 is fixed to the coaxial waveguide conversion section 15 with a bolt 18 via a waveguide-side inner conductor retainer 17 .
One end of the inner conductor 7 has an antenna portion 7a that protrudes into the acceleration cavity 5 .

A high-frequency input side end portion 7b of the inner conductor 7 and the other end (the end on the high-frequency transmission window structure 13 side) 8b of the waveguide-side inner conductor 8 are in contact with each other and are continuous.

The outer conductor 9 is provided coaxially with the inner conductor 7, and is connected to the acceleration cavity 5 via a flange 21 on the vacuum side at its end on the acceleration cavity 5 side. It is secured to an outer sleeve 23 (described below). The inner conductor 7, the vacuum-side flange 21 and the outer conductor 9 are assembled by brazing, welding, or the like after assembling a high-frequency transmission window structure 13 (described later) by brazing.

The high-frequency transmission window structure 13 includes a high-frequency transmission window 11 that maintains airtightness and transmits high frequencies, and an outer sleeve 23 and an inner sleeve 25 that constitute a transmission line. The high-frequency transmission window 11 has an annular shape, and the inner sleeve 25 is inserted through the ring to separate the vacuum side and the atmosphere side between the inner sleeve 25 and the outer sleeve 23 . Ceramic such as alumina is used as the material of the high-frequency transmission window 11 .

Outer sleeve 23 and inner sleeve 25 are made of copper.
The inner sleeve 25 is continuous with the inner conductor 7, and in this embodiment, the inner sleeve 25 and the inner conductor 7 are made of the same material.

The dielectric substrate 14 is provided on the high frequency input side of the high frequency transmission window 11 in the high frequency transmission window structure 13 . The dielectric substrate 14 is fixed to the high frequency transmission window structure 13 by brazing as will be described later.
The dielectric substrate 14 is made of alumina and has an annular shape.

The dielectric substrate 14 has an inner peripheral edge 14a brazed to the inner sleeve 25 of the high frequency transmission window structure 13 and an outer peripheral edge 14b brazed to the outer sleeve 23 of the high frequency transmission window structure 13, respectively.
Each brazing includes a first brazing material 27a disposed between the inner peripheral edge 14a of the dielectric substrate 14 and the outer peripheral surface of the inner sleeve 25, and the outer peripheral edge 14b of the dielectric substrate 14 and the inner peripheral surface of the outer sleeve 23. are brazed with a second brazing material 27b arranged between them.
In FIG. 1, the dashed-dotted lines indicate the arrangement of the brazing filler metals 27a and 27b. The first brazing material 27a and the second brazing material 27b are ribbon-shaped (thin belt-shaped) brazing materials.

A high-frequency transmission window structure connecting portion 29 is provided in the waveguide 3 at a position facing the coaxial waveguide conversion portion 15 .
In the high-frequency transmission window structure connecting portion 29, the atmosphere side flange 31 brazed to the outer sleeve 23 of the high-frequency transmission window structure 13 is sandwiched between the fastened portion 29a and the fastening portion 29b of the high-frequency transmission window structure connection portion 29. , the to-be-fastened portion 29a and the fastening portion 29b are fixed with bolts 32. As shown in FIG. The atmosphere-side flange 31 also functions as a centering flange for the high-frequency transmission window assembly 13 .

The high-frequency input coupler 1 according to the first embodiment is attached by fixing the waveguide-side inner conductor 8 and the waveguide-side inner conductor retainer 17 to the coaxial waveguide converter 15 with bolts 18 . Furthermore, it is more preferable to fix the inner conductor end portion 7b with a bolt.
On the other hand, the dielectric substrate 14 is fixed to the high frequency transmission window structure 13 between the outer sleeve 23 and the inner sleeve 25 by brazing, and the dielectric substrate 14 is fixed at the high frequency transmission window structure connecting portion 29. While centering the high-frequency transmission window structure 13 with the atmosphere side flange 31, the bolt 32 is tightened to fasten the fastened portion 29a and the fastened portion 29b.

The effects of this embodiment will be described.
Since the dielectric substrate 14 is fixed to the high frequency transmission window structure 13 by brazing, it is possible to prevent the formation of a gap between the dielectric substrate 14 and the high frequency transmission window structure 13 . That is, as in the prior art, the high-frequency input side end portion 7b of the inner sleeve (inner conductor) 25 of the high-frequency transmission window structure 13 and the waveguide whose one end portion is fixed to the coaxial waveguide conversion portion (doorknob) with the bolt 18. If the other end 8b of the tube-side inner conductor 8 were sandwiched and fixed, there was a risk of creating a gap between the dielectric substrate 14 and the sandwiched portion. Since the substrate 14 is fixed to the high frequency transmission window structure 13 by brazing, it is possible to prevent a gap from being formed between the dielectric substrate 14 and the high frequency transmission window structure 13 .

Further, the annular dielectric substrate 14 has its inner peripheral edge 14a brazed to the inner sleeve 25 of the high frequency transmission window structure 13, and its outer peripheral edge 14b brazed to the outer sleeve 23 of the high frequency transmission window structure 13. At both the inner peripheral edge 14a and the outer peripheral edge 14b of the body substrate 14, the occurrence of gaps can be prevented and the body substrate 14 can be firmly fixed.
The dielectric substrate 14 comprises a first brazing filler metal 27a arranged between its inner peripheral edge 14a and the outer peripheral surface of the inner sleeve 25, and a second brazing filler metal 27a arranged between its outer peripheral edge 14b and the inner peripheral surface of the outer sleeve 23. Since they are brazed with the material 27b, they are easy to manufacture.
Since the first brazing material 27a and the second brazing material 27b are ribbon-shaped brazing materials, they are easy to arrange.

Other embodiments will be described below. In the embodiments described below, portions having the same effects as those of the above-described first embodiment are denoted by the same reference numerals, and detailed descriptions of those portions will be given. Description is omitted.
A second embodiment will be described with reference to FIG.
In the second embodiment, the method of fixing the dielectric substrate 14 to the high frequency transmission window structure 13 is different.
The inner sleeve 25 of the high-frequency transmission window structure 13 is formed with an inner peripheral edge receiving portion 25a for receiving the inner peripheral edge 14a of the dielectric substrate 14. As shown in FIG. The inner peripheral edge receiving portion 25a is a recessed stepped portion.
The inner peripheral edge 14a of the dielectric substrate 14 is brazed to the inner sleeve 25 by a third brazing material 27c placed on the inner peripheral edge receiving portion 25a.
Further, the outer sleeve 23 of the high-frequency transmission window structure 13 is formed with an outer peripheral edge receiving portion 23a for receiving the outer peripheral edge 14b of the dielectric substrate 14. As shown in FIG. The outer peripheral edge receiving portion 23a is a recessed stepped portion.
The outer peripheral edge 14b of the dielectric substrate 14 is brazed to the inner sleeve 25 by the fourth brazing material 27d placed on the outer peripheral edge receiving portion 23a.

An inner peripheral presser 33 is provided on the inner peripheral edge of the dielectric substrate 14 to press it from the high frequency input side. Similarly, an outer periphery presser 35 is provided on the outer periphery of the dielectric substrate 14 to press it from the high frequency input side.
The high frequency input side surface of the inner peripheral presser 33 is brought into contact with the other end 8b of the waveguide-side inner conductor 8, and the outer peripheral presser 35 has its high frequency input side surface brought into contact with the fastened portion (waveguide side member) 29a. It is to be touched.
Each of the inner peripheral presser 33 and the outer peripheral presser 35 has an L-shaped cross section and is arranged so as to fit into the corresponding edge of the dielectric substrate 14 from the high frequency input side.
The inner peripheral side retainer 33 is soldered to the inner peripheral edge 14a of the dielectric substrate 14 by a fifth brazing material 27e placed on the high frequency input side surface.
The outer peripheral presser 35 is soldered to the outer peripheral edge 14b of the dielectric substrate 14 by a sixth brazing material 27f placed on the high frequency input side surface.

The high-frequency input coupler 1 according to the second embodiment is attached by fixing the waveguide-side inner conductor 8 and the waveguide-side inner conductor retainer 18 to the coaxial waveguide converter 15 with bolts 18 .
On the other hand, in the high frequency transmission window structure 13, the dielectric substrate 14, the inner peripheral presser 33 and the outer peripheral presser 35 are fixed by brazing between the outer sleeve 23 and the inner sleeve 25. 3, the high-frequency transmission window structure 13 to which the dielectric substrate 14, the inner peripheral presser 33, and the outer peripheral presser 35 are fixed is centered with the atmosphere side flange 31, and the bolts 32 are tightened to fasten the fastening portion 29a and the fastening portion 29b. As a result, the outer peripheral side of the dielectric substrate 14 is fixed by pressing the outer peripheral presser 35 brazed to the dielectric substrate 14 against the fastened portion 29 .
On the other hand, the inner peripheral retainer 33 brazed to the inner peripheral edge 14a of the dielectric substrate 14 is pressed against the other end 8b of the waveguide-side inner conductor 8 and fixed.

Effects of the second embodiment will be described.
According to the second embodiment, similarly to the first embodiment, the dielectric substrate 14 is fixed to the high frequency transmission window structure 13 by brazing, so that a gap is formed between the dielectric substrate 14 and the high frequency transmission window structure 13. can be prevented.
The third brazing material 27c for brazing the dielectric substrate 14 is placed on the stepped inner peripheral edge receiving portion 25a formed on the inner sleeve 25, and the fourth brazing material 27d is placed on the stepped inner peripheral edge receiving portion 25a formed on the outer sleeve 23. Therefore, the third brazing material 27c and the fourth brazing material 27d can be easily installed during brazing.
The inner peripheral retainer 33 is brazed with a fifth brazing material 27e placed on the high frequency input side surface of the inner peripheral edge 14a of the dielectric substrate 14, and the outer peripheral retainer 35 is brazed to the high frequency input side surface of the outer peripheral edge 14b of the dielectric substrate 14. Since it is brazed by the placed sixth brazing filler metal 27f, the brazing filler metals 27e and 27f can be easily installed during brazing.

The one embodiment described above is provided as an example and is not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.

REFERENCE SIGNS LIST 1 high-frequency input coupler 3 waveguide 5 accelerating cavity 7 inner conductor 9 outer conductor 11 high-frequency transmission window 13 high-frequency transmission window structure 14 dielectric substrate 14a inner Peripheral edge 14b... Outer peripheral edge 23... Outer sleeve 23a... Outer peripheral edge receiving part 25... Inner sleeve 25a... Inner peripheral edge receiving part 27a... First brazing material 27b... Second brazing material 27c... Third brazing material material 27d...fourth brazing material 27e...fifth brazing material 27f...sixth brazing material 33...inner circumference holder 35...periphery circumference holder.

Claims (5)

A high-frequency input coupler provided between a waveguide and an accelerating cavity for inputting high-frequency waves from the waveguide to the accelerating cavity, comprising: an inner conductor; an outer conductor provided around the inner conductor; A high-frequency transmission window structure having a window, and a dielectric substrate provided on the high-frequency input side of the high-frequency transmission window,
A high-frequency input coupler, wherein said dielectric substrate is fixed to said high-frequency transmission window structure by brazing. 2. A high frequency input according to claim 1, wherein said dielectric substrate has an annular shape and has an inner peripheral edge brazed to an inner sleeve of said high frequency transmission window structure and an outer peripheral edge brazed to an outer sleeve of said high frequency transmission window structure. combiner. 3. The dielectric substrate is brazed with a brazing material disposed between the inner peripheral edge and the outer peripheral surface of the inner sleeve and between the outer peripheral edge and the inner peripheral surface of the outer sleeve. A high frequency input coupler as described. The inner sleeve is formed with a stepped inner peripheral edge receiving portion for receiving the inner peripheral edge of the dielectric substrate, and the outer sleeve is formed with a stepped outer peripheral edge receiver for receiving the outer peripheral edge of the dielectric substrate. 3. The dielectric substrate is brazed to the inner sleeve and the outer sleeve with brazing material placed on the inner peripheral edge receiving portion and the outer peripheral edge receiving portion. High frequency input coupler. An inner peripheral presser presses the inner peripheral edge of the dielectric substrate from the high frequency input side, and an outer peripheral presser presses the outer peripheral edge of the dielectric substrate from the high frequency input side, wherein the inner peripheral presser presses the high frequency input side surface. a waveguide-side inner conductor is abutted against the waveguide-side member;
The dielectric substrate is brazed with a brazing material placed on the high-frequency input side surface at positions corresponding to the inner periphery pressing member and the outer periphery pressing member, and the inner periphery pressing member and the outer periphery pressing member are brazed to the dielectric substrate. 5. A high frequency input coupler as claimed in claim 4.

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