Microwave tube and method for controlling microwave tube

Abstract

A microwave tube and a method for controlling the microwave tube are provided. The microwave tube can suppress complex structures and adjustments, and helps maintain the microwave tube's high-frequency output constant over the long term. The microwave tube includes: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam that passes through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused in the magnetic circuit and utilizes the circuit to propagate high frequencies; and a magnetic assembly that is arranged so as to be movable around the electron gun in the direction of electron beam emission. The microwave tube is configured so that the magnetic assembly is moved in the direction of electron beam emission, thereby controlling the high-frequency output from the high-frequency circuit to be constant.

Description

Technical Field

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS]

[0002] The present invention is based on a claim of priority to Japanese patent application JP2019-218548 (filed on December 3, 2019), the entire contents of which are incorporated herein by reference and set forth herein.

[0003] The invention relates to a microwave tube and a method for controlling the microwave tube. Background Art

[0004] A microwave tube is a device used to amplify electromagnetic waves (high frequencies) in the microwave band (0.3 to 300 GHz). The microwave tube amplifies and outputs the high frequencies input by the microwave tube by allowing the high frequencies to interact with the electron beam emitted by the electron gun. For example Figure 5 As shown, a microwave tube 1 includes: an electron gun 10 that emits an electron beam 2; a magnetic circuit 40 that focuses the electron beam 2 emitted from the electron gun 10; a collector 30 that captures the electron beam 2 that passes through the magnetic circuit 40; and a high-frequency circuit 50 that is spirally arranged around the electron beam 2 focused by the magnetic circuit 40 and transmits a high frequency (see, for example, Patent Document (PTL) 1). In this microwave tube 1, a high frequency supplied from an inlet 51 of the high-frequency circuit 50 is amplified by interaction with the electron beam 2 and output from an outlet 52 of the high-frequency circuit 50.

[0005] This type of microwave tube 1 presents the following problems. For example, as the electron gun 10 ages, the amount of electron beam 2 emitted from the electron gun 10 decreases, and the high-frequency amplification effect also decreases in response to these changes. Furthermore, the magnetic flux density generated in the magnetic circuit 40 increases or decreases depending on changes in ambient temperature, increasing or decreasing the high-frequency amplification effect. Furthermore, the magnetic flux density of the magnetic circuit 40 decreases as the magnetic circuit 40 ages, causing the diameter of the electron beam 2 to increase. This increases the number of collisions between the electron beam 2 and the high-frequency circuit 50, thus shortening the life of the microwave tube 1.

[0006] In order to solve these problems, such as Figure 5 As shown, auxiliary electromagnets 60 (see, for example, PTL 2) may be arranged around the electron gun 10. By changing the generated magnetic flux density using the auxiliary electromagnets 60, the diameter of the electron beam and the high-frequency output can be adjusted.

[0007] Reference List

[0008] Patent Literature

[0009] [PTL 1]JP2007–234344A

[0010] [PTL 2]JP09-237582A Summary of the Invention

[0011] Technical issues

[0012] The following analysis is given by the inventors of the present application.

[0013] However, in a microwave tube 1 having an auxiliary electromagnet 60, the heat generated by the auxiliary electromagnet 60 reduces the magnetic flux density generated by the auxiliary electromagnet 60, making it difficult to maintain a constant high-frequency output over a long period of time. Furthermore, in PTL 2, the increase / decrease in the high-frequency amplification effect is suppressed by reducing the current flowing through the auxiliary electromagnet 60 and making the position of the electron gun 10 adjustable in the axial direction. However, this complicates the structure and adjustment (control) because both the current flowing through the auxiliary electromagnet 60 and the position of the electron gun 10 must be adjusted. Furthermore, in a structure that adjusts the position of the electron gun 10, the travel distance of the electron beam 2 changes, making it difficult to maintain a constant high-frequency output over a long period of time.

[0014] The main object of the present invention is to provide a microwave tube and a method for controlling the microwave tube, which can help keep the high-frequency output of the microwave tube constant for a long time without complex structure or adjustment.

[0015] Solution to the problem

[0016] The microwave tube relating to the first aspect is configured to include: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam passing through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and a magnetic body component that is arranged around the electron gun so as to be movable in the emission direction of the electron beam, and by moving the magnetic body component in the emission direction of the electron beam, the high-frequency output from the high-frequency circuit is controlled to be constant.

[0017] The method for controlling a microwave tube relating to the second aspect is a method for controlling a microwave tube, wherein the microwave tube includes: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam passing through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and a magnetic body component that is arranged around the electron gun so as to be movable in the emission direction of the electron beam, and wherein the method includes controlling the high-frequency output from the high-frequency circuit to be constant by moving the magnetic body component in the emission direction of the electron beam.

[0018] Advantageous Effects of the Invention

[0019] According to the first and second aspects, it is possible to help keep the high-frequency output of the microwave tube constant for a long period of time without complicated structure or adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a cross-sectional view schematically showing the configuration of a microwave tube related to the first exemplary embodiment.

[0021] Figure 2 Schematic diagram for explaining the axial distance “d” between the magnetic member and the cathode in the microwave tube related to the first exemplary embodiment.

[0022] Figure 3 : is a graph schematically showing the relationship between the axial distance "d" between the magnetic body member and the cathode, the beam diameter, and the output in the microwave tube related to the first exemplary embodiment.

[0023] Figure 4 is a cross-sectional view schematically showing the configuration of a microwave tube related to the second exemplary embodiment.

[0024] Figure 5 is a cross-sectional view schematically showing the configuration of a microwave tube related to a conventional example. DETAILED DESCRIPTION

[0025] model

[0026] In the present disclosure described below, microwave tubes related to Mode 1 and modified modes thereof may be appropriately selected and combined.

[0027] The microwave tube associated with mode 1 can be configured to include: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam passing through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and a magnetic body component that is arranged around the electron gun so as to be movable in the emission direction of the electron beam, wherein the high-frequency output from the high-frequency circuit is controlled to be constant by moving the magnetic body component in the emission direction of the electron beam.

[0028] As a modified mode of the microwave tube related to Mode 1, the microwave tube may further include a position moving mechanism capable of moving the position of the magnetic member in the emission direction of the electron beam.

[0029] As a modified mode of the microwave tube related to Mode 1, the microwave tube may further include a control component that controls the operation of the position moving mechanism.

[0030] As a variant mode of the microwave tube related to mode 1, the microwave tube may also include a helix current detection component, which detects the helix current generated when the electron beam collides with the high-frequency circuit, wherein the control component can control the operation of the position moving mechanism based at least on the helix current detected by the helix current detection component.

[0031] As a variation mode of the microwave tube related to mode 1, the microwave tube may further include a beam cutter that adjusts the electron beam emitted from the electron gun so that the electron beam does not enter the high-frequency circuit, wherein the helical current detection component can detect the helical current flowing between the high-frequency circuit and the beam cutter.

[0032] As a modified mode of the microwave tube related to Mode 1, when the helical current detected by the helical current detection component increases, the control component controls the position of the magnetic component to become closer to the magnetic circuit until the helical current reaches a first target value.

[0033] As a variant mode of the microwave tube related to mode 1, the microwave tube may also include a high-frequency output detection component that detects the level of the high-frequency output from the high-frequency circuit, and the control component may control the position of the magnetic body component using a position movement mechanism based at least on the high-frequency output level detected by the high-frequency output detection component.

[0034] As a variation mode of the microwave tube related to mode 1, when the high-frequency output level detected by the high-frequency output detection component decreases, the control component can control the position of the magnetic component to become closer to the magnetic circuit until the high-frequency output level reaches a second target value.

[0035] In the present disclosure, as a method for controlling a microwave tube involving mode 2, a method for controlling a microwave tube is provided, wherein the microwave tube includes: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam passing through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and a magnetic body component that is arranged around the electron gun so as to be movable in the emission direction of the electron beam, and wherein the method may include controlling the high-frequency output from the high-frequency circuit to be constant by moving the magnetic body component in the emission direction of the electron beam.

[0036] As a variation mode of the method of controlling a microwave tube related to mode 2, the method may include controlling the position of the magnetic body component to become closer to the magnetic circuit when the helical current generated by the collision between the electron beam and the high-frequency circuit increases or the high-frequency output level from the high-frequency circuit decreases until the helical current or the high-frequency output level reaches a target value.

[0037] The following exemplary embodiments are described with reference to the accompanying drawings. When reference numerals are added to this application, it should be noted that the reference numerals given herein are primarily for ease of understanding and are not intended to limit the present invention to the aspects shown. In addition, the following exemplary embodiments are merely illustrative and do not limit the present invention.

[0038] [First exemplary embodiment]

[0039] A microwave tube related to a first exemplary embodiment will be described below with reference to the drawings. Figure 1 is a cross-sectional view schematically showing the configuration of a microwave tube related to the first exemplary embodiment.

[0040] Microwave tube 1 is an electron tube that amplifies the high frequency energy supplied by electron beam 2 emitted from electron gun 10 to generate a resulting output. Microwave tube 1 includes: electron gun 10; beam cutter 20; collector 30; magnetic circuit 40; and high-frequency circuit 50, all contained within a sealed (vacuum) space. Furthermore, microwave tube 1 includes: a magnetic component 70; a position shifting mechanism 71; a control component 72; a helical current detection component 73; and a high-frequency output detection component 74, as components for maintaining a constant high-frequency output over a long period of time.

[0041] The electron gun 10 is a device (equipment) that (linearly) emits an electron beam 2. The electron gun 10 is arranged on the opposite side of the collector 30 relative to the magnetic circuit 40. For example, as the electron gun 10, a thermal electron emission type electron gun can be used, in which electrons heated by the heater 13 in the cathode 11 (emitter) are emitted into space, and the emitted electrons are focused by the Wehnelt electrode 12 to form the electron beam 2. The formed electron beam 2 is accelerated by the potential difference between the cathode 11 and the anode 14 and guided to the beam cutter 20. A body voltage, which is a negative DC voltage relative to the potential of the high-frequency circuit 50, is supplied to each of the cathode 11 and the Wehnelt electrode 12. A heater voltage, which is a positive DC voltage or a negative DC voltage relative to the potential of the cathode 11, is supplied to the heater 13. An anode voltage, which is a positive DC voltage relative to the potential of the cathode 11, is supplied to the anode 14.

[0042] The beam cutter 20 is an annular member that adjusts the electron beam 2 emitted from the electron gun 10 so that the electron beam 2 does not enter the high-frequency circuit 50. The beam cutter 20 is arranged in the magnetic circuit 40 between the electron gun 10 and the high-frequency circuit 50. As the beam cutter 20, a metal material having a heat capacity greater than the heat capacity of the high-frequency circuit 50 can be used. The beam cutter 20 collides with the electron beam 2 scattered outside the inner diameter of the spiral portion of the high-frequency circuit 50 and prevents the scattered electron beam 2 from entering the high-frequency circuit 50. The beam cutter 20 is electrically connected to the helical current detection component 73.

[0043] The collector 30 is an electrode that captures the electron beam 2 that has passed through the high-frequency circuit 50. The collector 30 is arranged on the opposite side of the electron gun 10 relative to the magnetic circuit 40. A collector voltage, which is a positive DC voltage relative to the potential of the cathode 11, is supplied to the collector 30.

[0044] The magnetic circuit 40 is a loop (a periodic magnetic device) that uses magnetism to focus the electron beam 2 emitted from the electron gun 10 over the entire length of the high-frequency circuit 50. The magnetic circuit 40 is arranged outside the periphery of the spiral portion of the high-frequency circuit 50. The beam cutter 20 is arranged closer to the electron gun 10 than the spiral portion of the high-frequency circuit 50 within the magnetic circuit 40. As the magnetic circuit 40, an electromagnet and / or a permanent magnet can be used.

[0045] The high-frequency circuit 50 is a circuit (spiral circuit) that is spirally arranged around the electron beam 2 that has passed through the beam cutter 20 and transmits high frequency. The spiral portion of the high-frequency circuit 50 is arranged between the electron beam 2 and the magnetic circuit 40. As the high-frequency circuit 50, a conductor can be used. In the high-frequency circuit 50, the high frequency fed to the entrance 51 of the high-frequency circuit 50 is transmitted through the spiral portion of the high-frequency circuit 50 and output from the exit 52 of the high-frequency circuit 50. The high-frequency circuit 50 amplifies and outputs the high frequency when the high frequency propagates through the spiral portion of the high-frequency circuit 50 by interacting with the electron beam 2 that has passed through the beam cutter 20 (the kinetic energy of the electron beam is converted into microwave energy). The high-frequency circuit 50 is electrically connected to the spiral current detection component 73. The high-frequency circuit 50 is electrically connected to the high-frequency output detection component 74.

[0046] The magnetic component 70 is a component including a magnetic body that focuses the electron beam 2 emitted from the electron gun 10 (mainly from the cathode 11). As the magnetic component 70, a permanent magnet can be used. The magnetic component 70 is arranged around the electron gun 10 and is movable in the axial direction (the emission direction of the electron beam 2). The magnetic component 70 is moved in the axial direction by a position moving mechanism 71. The axial position or length of the electron beam 2 emitted from the cathode 11 can be adjusted by moving the magnetic component 70 in the axial direction. When the axial position of the magnetic component 70 is changed, the diameter of the electron beam is changed by changing the magnetic field affecting the cathode 11. This affects the interaction between the electron beam 2 and the high frequency propagating through the high frequency circuit 50, thereby changing the high frequency output of the microwave tube 1.

[0047] The position moving mechanism 71 is a mechanism capable of axially moving the magnetic member 70 . For example, a combination of a rack and pinion mechanism and a motor, or a solenoid, can be used as the position moving mechanism 71 . The operation of the position moving mechanism 71 is controlled by a control unit 72 .

[0048] The control component 72 is a functional component that controls the operation of the position shifting mechanism 71. For example, an integrated circuit can be used as the control component 72. The control component 72 stores a database that organizes the output variation (variation in high-frequency output) relative to the position of the magnetic component 70 and the corresponding relationship with the electron beam diameter. The control component 72 is electrically connected to the helical current detection component 73 and uses the helical current detection component 73 to monitor the current (helical current) generated when the electron beam 2 collides with the high-frequency circuit 50. The control component 72 is electrically connected to the high-frequency output detection component 74 and uses the high-frequency output detection component 74 to monitor the high-frequency output level from the outlet 52 of the high-frequency circuit 50. Based on the monitored helical current and high-frequency output level, the control component 72 uses the position shifting mechanism 71 to control the position of the magnetic component 70. When the helical current increases or the high-frequency output level decreases, the control component 72 controls the position of the magnetic component 70 to be closer to the magnetic circuit 40 until the helical current or high-frequency output level reaches the target value.

[0049] Here, because control unit 72 already knows the relationship between the high-frequency output and the helical current relative to the position of magnetic member 70, control unit 72 controls the position of magnetic member 70 so that it can move the position of magnetic member 70 in response to changes in the high-frequency output or the helical current until the high-frequency output or the helical current reaches the target value. This control process maintains the high-frequency output constant while suppressing increases in the helical current.

[0050] The helical current detection component 73 is a functional component that detects a current (helical current) generated when the electron beam 2 collides with the high-frequency circuit 50. The helical current detection component 73 is electrically connected to the high-frequency circuit 50 and the beam cutter 20. The helical current detection component 73 detects the helical current flowing between the high-frequency circuit 50 and the beam cutter 20, and provides the value of the detected helical current to the control component 72.

[0051] The high-frequency output detection section 74 is a functional section that detects the high-frequency output level from the outlet 52 of the high-frequency circuit 50. The high-frequency output detection section 74 is electrically connected to the area near the outlet 52 of the high-frequency circuit 50. The high-frequency output detection section 74 provides the value of the detected high-frequency output level to the control section 72.

[0052] The relationship between the axial distance "d" between the magnetic body member and the cathode in the microwave tube related to the first exemplary embodiment and the beam diameter and output will be described below with reference to the drawings. Figure 2 Schematic diagram for explaining the axial distance “d” between the magnetic member and the cathode in the microwave tube related to the first exemplary embodiment. Figure 3: is a graph schematically showing the relationship between the axial distance "d" between the magnetic body member and the cathode, the beam diameter, and the output in the microwave tube related to the first exemplary embodiment.

[0053] like Figure 2 As shown, when the axial distance between the magnetic body member 70 and the cathode 11 is defined as the distance "d" between the axial center line 70a passing through the axial center of the magnetic body member 70 and the axial center line 11a passing through the axial center of the cathode 11, the electron beam diameter and the high frequency output vary according to the change of the distance "d", as shown in FIG. Figure 3 shown.

[0054] exist Figure 3 In the region “A”, since the high frequency output increases as the distance “d” increases, the high frequency output can be controlled to increase by moving the magnetic member 70 to increase the distance “d”.

[0055] exist Figure 3 In the region "B", since the high frequency output decreases as the distance "d" increases, the high frequency output can be controlled to increase by moving the magnetic member 70 to reduce the distance "d".

[0056] According to the first exemplary embodiment, the high-frequency output of microwave tube 1 can be adjusted during operation by controlling the position of magnetic member 70 using position shifting mechanism 71. This helps maintain the high-frequency output of microwave tube 1 constant over the long term without requiring complex structures or adjustments. Furthermore, according to the first exemplary embodiment, the high-frequency output of microwave tube 1 can be adjusted while monitoring the helical current and high-frequency output level. This allows the high-frequency output to be maintained constant regardless of changes in ambient temperature (changes in the magnetic flux density temperature of magnetic circuit 40). Furthermore, since the high-frequency output of microwave tube 1 can be adjusted while monitoring the helical current and high-frequency output level, the increase in helical current over time (due to aging of magnetic circuit 40) can be suppressed, allowing for stable operation of the microwave tube over the long term. Furthermore, since the high-frequency output of microwave tube 1 can be adjusted while monitoring the helical current and high-frequency output level, high-load conditions (high helical current) can be alleviated during startup of microwave tube 1. Furthermore, by setting priorities and acceptable ranges for the aforementioned effects and prioritizing the high-priority effect within the acceptable range, the high-frequency output can be maintained constant even between conflicting effects without causing any control program failures.

[0057] [Second exemplary embodiment]

[0058] A microwave tube related to a second exemplary embodiment will be described below with reference to the drawings. Figure 4is a cross-sectional view schematically showing the configuration of a microwave tube related to the second exemplary embodiment.

[0059] The microwave tube 1 is an electron tube that amplifies and outputs a supplied high frequency by causing the high frequency to interact with an electron beam 2 emitted from an electron gun 10. The microwave tube 1 includes: an electron gun 10; a beam cutter 20; a collector 30; a magnetic circuit 40; a high frequency circuit 50; and a magnetic member 70.

[0060] Electron gun 10 emits electron beam 2. Magnetic circuit 40 focuses electron beam 2 emitted from electron gun 10. A collector captures electron beam 2 that passes through magnetic circuit 40. High-frequency circuit 50 is spirally arranged around electron beam 2 focused by magnetic circuit 40 and transmits high frequency. Magnetic member 70 is arranged around electron gun 10 so as to be movable in the direction of electron beam emission.

[0061] The microwave tube 1 is configured to control the high-frequency output from the high-frequency circuit 50 to be constant by moving the magnetic member 70 in the emission direction of the electron beam 2 .

[0062] According to the second exemplary embodiment, since the high frequency output of microwave tube 1 can be adjusted by controlling the position of magnetic body member 70 during operation thereof, it is possible to help keep the high frequency output of microwave tube 1 constant for a long period without complex structure or adjustment.

[0063] A part or all of the above exemplary embodiments may be described as, but not limited to, the following modes.

[0064] [Mode 1]

[0065] A microwave tube, comprising:

[0066] an electron gun that emits an electron beam;

[0067] a magnetic circuit that focuses the electron beam emitted from the electron gun;

[0068] a collector, which captures the electron beam that passes through the magnetic circuit;

[0069] a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and

[0070] A magnetic member is arranged around the electron gun so as to be movable in the emission direction of the electron beam, wherein

[0071] By moving the magnetic member in the direction of electron beam emission, the high-frequency output from the high-frequency circuit is controlled to be constant.

[0072] [Mode 2]

[0073] The microwave tube according to mode 1 further includes a position moving mechanism capable of moving the position of the magnetic member in the emission direction of the electron beam.

[0074] [Mode 3]

[0075] The microwave tube according to Mode 2 further comprises a control section that controls the operation of the position moving mechanism.

[0076] [Mode 4]

[0077] The microwave tube according to Mode 3 further comprises a helical current detection component for detecting a helical current generated when the electron beam collides with the high-frequency circuit, wherein:

[0078] The control section controls the operation of the position moving mechanism based on at least the solenoid current detected by the solenoid current detection section.

[0079] [Mode 5]

[0080] The microwave tube according to mode 4 further comprises a beam cutter that adjusts the electron beam emitted from the electron gun so that the electron beam does not enter the high-frequency circuit, wherein

[0081] The helical current detection section detects a helical current flowing between the high-frequency circuit and the beam cutter.

[0082] [Mode 6]

[0083] The microwave tube according to mode 4 or 5, wherein

[0084] When the helical current detected by the helical current detection component increases, the control component controls the position of the magnetic body component to become closer to the magnetic circuit until the helical current reaches a first target value.

[0085] [Mode 7]

[0086] The microwave tube according to any one of modes 3 to 6, further comprising a high-frequency output detection part that detects a level of a high-frequency output from the high-frequency circuit, wherein

[0087] The control unit controls the position of the magnetic member using the position moving mechanism based on at least the high-frequency output level detected by the high-frequency output detection unit.

[0088] [Mode 8]

[0089] The microwave tube according to Mode 7, wherein:

[0090] When the high-frequency output level detected by the high-frequency output detection component decreases, the control component controls the position of the magnetic member to become closer to the magnetic circuit until the high-frequency output level reaches a second target value.

[0091] [Mode 9]

[0092] A method for controlling a microwave tube,

[0093] The microwave tube includes:

[0094] an electron gun that emits an electron beam;

[0095] a magnetic circuit that focuses the electron beam emitted from the electron gun;

[0096] a collector, which captures the electron beam that passes through the magnetic circuit;

[0097] a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits high frequency; and

[0098] a magnetic member arranged around the electron gun so as to be movable in the direction of emission of the electron beam, and

[0099] The method includes controlling the high-frequency output from the high-frequency circuit to be constant by moving a magnetic member in the emission direction of the electron beam.

[0100] [Mode 10]

[0101] The method for controlling a microwave tube according to mode 9 includes: when the helical current generated by the collision between the electron beam and the high-frequency circuit increases or the level of the high-frequency output from the high-frequency circuit decreases, controlling the position of the magnetic body component to become closer to the magnetic circuit until the helical current or the high-frequency output level reaches a target value.

[0102] The disclosures of the above-mentioned patent documents should be incorporated into this application and described by reference, and used as the basis of the present invention or part of the present invention as needed. It should be noted that the exemplary embodiments or examples can be modified or adjusted within the entire disclosure of the present invention (including the claims and drawings) based on the basic technical concept of the present invention. In addition, various disclosed elements (including the individual elements of the individual claims, the individual elements of the individual exemplary embodiments or examples, the individual elements of the individual drawings, etc.) can be combined or selected (or deselected when necessary) in various ways within the entire disclosure of the present invention. That is to say, it goes without saying that the present invention includes any type of changes and modifications that can be achieved by those skilled in the art based on the entire disclosure including the claims and drawings and the technical concept of the present invention. In addition, for any numerical value or range disclosed herein, any intermediate value or smaller value or sub-range should be described even if there is no explicit description. In addition, when necessary, according to the purpose of the present invention, each disclosed matter of the above-mentioned referenced document is used in combination with part or all of the matters described herein (as part of the disclosure of the present invention) as included in (belonging to) the matters disclosed in the present application.

[0103] Reference Signs List

[0104] 1: Microwave tube

[0105] 2: Electron beam

[0106] 10: Electron gun

[0107] 11: cathode

[0108] 11a: Axial centerline

[0109] 12: Wehner electrode

[0110] 13: Heater

[0111] 14: Anode

[0112] 20: Beam Cutter

[0113] 30: Collector

[0114] 40: Magnetic Circuit

[0115] 50: High-frequency circuit

[0116] 51: Entrance

[0117] 52: Export

[0118] 60: Auxiliary electromagnet

[0119] 70: Magnetic parts

[0120] 70a: Axial centerline

[0121] 71: Position moving mechanism

[0122] 72: Control components

[0123] 73: Spiral current detection component

[0124] 74: High frequency output detection component

Claims

1. A microwave tube, comprising: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam that has passed through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits a high frequency; a permanent magnet arranged around the electron gun so as to be movable in an emission direction of the electron beam; a helical current detecting section that detects a helical current generated when the electron beam collides with the high-frequency circuit; and a beam cutter that adjusts the electron beam emitted from the electron gun so that the electron beam does not enter the high-frequency circuit, wherein The helical current detection section detects the helical current flowing between the high-frequency circuit and the beam cutter, and Based on the helical current detected by the helical current detection element, the high-frequency output from the high-frequency circuit is controlled to be constant by moving the permanent magnet in the emission direction of the electron beam. 2 . The microwave tube according to claim 1 , further comprising a position moving mechanism capable of moving the position of the permanent magnet in the emission direction of the electron beam. 3 . The microwave tube according to claim 2 , further comprising a control part that controls the operation of the position moving mechanism.

4. The microwave tube according to claim 3, wherein: When the helical current detected by the helical current detection section increases, the control section controls the position of the permanent magnet to become closer to the magnetic circuit until the helical current reaches a first target value.

5. The microwave tube according to claim 3 or 4, further comprising a high-frequency output detection component configured to detect a level of the high-frequency output from the high-frequency circuit, wherein: The control section controls the position of the permanent magnet using the position movement mechanism based on at least the high-frequency output level detected by the high-frequency output detection section.

6. The microwave tube according to claim 5, wherein: When the high-frequency output level detected by the high-frequency output detection section decreases, the control section controls the position of the permanent magnet to become closer to the magnetic circuit until the high-frequency output level reaches a second target value.

7. A method for controlling a microwave tube, in, The microwave tube comprises: an electron gun that emits an electron beam; a magnetic circuit that focuses the electron beam emitted from the electron gun; a collector that captures the electron beam that has passed through the magnetic circuit; a high-frequency circuit that is spirally arranged around the electron beam focused by the magnetic circuit and transmits a high frequency; a permanent magnet arranged around the electron gun so as to be movable in an emission direction of the electron beam; a helical current detecting section that detects a helical current generated when the electron beam collides with the high-frequency circuit; and a beam cutter that adjusts the electron beam emitted from the electron gun so that the electron beam does not enter the high-frequency circuit, The helical current detection component detects the helical current flowing between the high-frequency circuit and the beam cutter, and the method includes: based on the helical current detected by the helical current detection component, controlling the high-frequency output from the high-frequency circuit to be constant by moving the permanent magnet in the emission direction of the electron beam.

8. The method for controlling a microwave tube according to claim 7, comprising: When the helical current generated by the collision between the electron beam and the high-frequency circuit increases or the level of the high-frequency output from the high-frequency circuit decreases, the position of the permanent magnet is controlled to become closer to the magnetic circuit until the helical current or the high-frequency output level reaches a target value.

Images