JPH0541169A - Linear beam type microwave tube device - Google Patents

Abstract

PURPOSE:To disperse an electron beam caught at an inner wall of a collector electrode preferably, restrict generation of an induction current at the collector electrode or a cooling jacket, and restrict generation of Joule's heat securely. CONSTITUTION:A sweeping frequency of a current supplied to electromagnetic coils 20, 21 disposed around a collector part 16 for sweeping electrons incidental to the collector part by an AC magnetic field is set to be 10Hz or less (excluding 0).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a beam rectilinear microwave tube device for oscillating or amplifying microwave power, such as a gyrotron, a klystron, or a traveling wave tube, and more particularly to improvement of a collector section.

[0002]

2. Description of the Related Art As is well known, a beam rectilinear microwave tube device as described above has an electron gun section for generating an electron beam,
A high-frequency acting part such as a resonant cavity part or a slow wave circuit arranged downstream of the beam, a collector part arranged further downstream of the beam, a magnetic field device for electron beam focusing, and a power supply device for applying an operating voltage to each part. It is configured with.

By the way, recently, the increase in the high frequency output power is remarkable, and it is necessary to disperse the electron beam, which has been used through the high frequency acting section, as evenly as possible on the collector electrode wall. . To this end, a technique in which an electromagnetic coil is arranged around the collector electrode, an alternating current is caused to flow through the electromagnetic coil, and the electron beam is dispersed by the sweeping magnetic field is known, for example, in Japanese Patent Laid-Open No. 62-278732.

[0004]

The current supplied to the electron beam sweeping electromagnetic coil is usually supplied from a commercial power source of 50 Hz or 60 Hz after converting it into an appropriate voltage with the frequency unchanged. In addition, in the above publication, 10 to 10
An example of supplying a 0 Hz sine wave is shown. However, the collector electrode or the cooling jacket for cooling the collector electrode is a metal cylinder such as copper or stainless steel, and an induction current is generated in the collector electrode and the jacket by the alternating magnetic field generated by the electromagnetic coil.

This induced current cancels the magnetic field inside the collector electrode that sweeps and diffuses the electron beam to weaken the magnetic field strength, and also generates Joule heat in the collector electrode and the jacket itself. The generation of this Joule heat increases as the frequency of the current flowing through the electromagnetic coil increases, and cannot be ignored.

The present invention eliminates the above-mentioned inconveniences, satisfactorily disperses the electron beam trapped on the inner wall of the collector electrode, generates an induced current to the collector electrode and the cooling jacket, and thereby generates Joule heat. An object of the present invention is to provide a beam straight-moving type microwave tube device capable of suppressing the above.

[0007]

According to the present invention, the sweep frequency of the current flowing in the electromagnetic coil which is arranged around the collector portion and sweeps the electrons incident on the collector portion by the alternating magnetic field is less than 10 Hz (not including 0). ) Is a straight beam type microwave tube device.

[0008]

According to the present invention, since the sweep frequency of the current flowing through the electromagnetic coil is as low as less than 10 Hz, the generation of the induced current in the collector electrode and the cooling jacket is extremely small, so that the Joule heat generated in them is also ignored. The electron beam is suppressed as much as possible, and the electron beam trapped on the inner wall of the collector electrode can be well dispersed with a smaller electromagnetic coil current.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example in which the present invention is applied to a gyrotron will be described below with reference to the drawings. As shown in FIG. 1, the gyrotron body 11 includes an electron gun section 12 for generating a hollow electron beam, a high-frequency working section having a resonance cavity (not shown) arranged downstream of the beam, and a lateral direction downstream of the beam. It is provided with a high frequency output section 13 arranged, and a collector section 16 having a bell-shaped copper collector electrode 14 and a stainless steel evaporative cooling jacket 15 arranged at the most downstream side. Electron beam focusing electromagnetic coil 1 around the electron gun
7. Superconducting coils 18 for generating a magnetic field for rotating the electrons interacting with the millimeter-wave electric field of the resonance cavity at the cyclotron frequency are arranged in the high-frequency action section.

Therefore, four ring-shaped electromagnetic coils 19, 20, 21, 22 are vertically arranged in the outer periphery of the collector portion 16 at predetermined intervals in the direction of the collector axis. These electromagnetic coils consist of a number of columns 23,2 installed around the collector.
It is attached to 4 so that its axial position can be changed by a plurality of pairs of nuts 25, 25 .... Thereby,
Each electromagnetic coil can be adjusted and set to the optimum position. Then, DC currents are supplied from the DC power supplies 26 and 27 to the electromagnetic coil 19 on the most upstream side of the beam and the electromagnetic coil 22 on the most downstream side of the beam. Thereby, the distribution of the DC magnetic field inside the collector electrode is adjusted and set so that the incident electron beam is moderately focused or diffused. The remaining two electromagnetic coils 20 and 21 arranged between these two electromagnetic coils are arranged at appropriate axial intervals, and an alternating current is supplied from an AC power supply 28 to these coils. The sweep frequency of this supply alternating current is
The frequency is set to less than 10 Hz, more preferably 5 Hz or less. The magnetic field generated from each of the two electromagnetic coils 20 and 21 changes in the space inside the collector electrode 14 at the frequency, and sweeps and disperses the collision position of the incident electron beam on the inner wall of the collector electrode.

The two electromagnetic coils 20 and 21 are preferably formed by cutting at least one position in the circumferential direction of a bobbin 31 which is made of metal and has a U-shaped cross section as shown in FIGS. Then, a thin resin insulator 32 is sandwiched here, and the conducting wire 33 is wound in a coil shape, for example, 500 turns. As described above, since the bobbin 31 is electrically cut at at least one position in the circumferential direction, the induced current generated in the bobbin can be further reduced.

The electromagnetic coil 20 of the embodiment shown in FIGS. 4 and 5.
In (21), a slit 33 is formed in at least one place while leaving the outer peripheral portion of the bobbin 31 a little. The slit 33 can further reduce the induced current generated in the bobbin.

[0013]

As described above, according to the present invention, since the sweep frequency of the current flowing through the electromagnetic coil arranged around the collector is set to less than 10 Hz, the induced current to the collector electrode and the cooling jacket is reduced. Can be reduced, and the Joule heat generated in them can be suppressed to a negligible level. Therefore, the electron beam trapped on the inner wall of the collector electrode can be satisfactorily swept and dispersed with a smaller electromagnetic coil current.

[Brief description of drawings]

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

FIG. 2 is a half sectional view showing a part of an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a main part of FIG.

FIG. 4 is a half sectional view showing a part of another embodiment of the present invention.

5 is a cross-sectional view showing the main parts of FIG.

[Explanation of symbols] 11 ... Gyrotron body, 12 ... Electron gun section, 13 ... High frequency acting section, 16 ... Collector section, 19, 20, 21, 22 ... Electromagnetic coil, 28
…Power supply.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaki Tsuneoka, No. 1 at 801 Mukaiyama, Naka-cho, Naka-cho, Naka-gun, Ibaraki Prefecture, Japan Naka Research Institute, Japan Atomic Energy Research Institute 1 Stock company Toshiba Nasu electron tube factory

Claims (1)

[Claims] 1. An electron gun section, a high-frequency acting section arranged downstream of the beam, a collector section arranged downstream of the beam, and an electron arranged around the collector section and incident on the collector section by an alternating magnetic field. In a beam rectilinear microwave tube device including an electromagnetic coil for sweeping and a coil energizing power source for supplying a current to the electromagnetic coil, the sweep frequency of the current flowing through the electromagnetic coil is set to less than 10 Hz. Straight beam type microwave tube device characterized by.