JPH0498732A - Microwave tube device - Google Patents

Abstract

PURPOSE:To keep the degree of vacuum of an electron gun part at a satisfactorily proper level by fixing an evacuating ion pump to a heater terminal board via a pipe and providing a high voltage power source nearby this ion pump. CONSTITUTION:A pair of heater terminal boards 3, 4 are provided on an end part of an electron gun part 1 and an evacuating ion pump 6 is fixed to the terminal board 3 via a metal pipe 5. Further a high voltage power source 7 is provided near the pump 6 and the input side of the power source 7 is connected via a lead wire 8 to the heater terminal board 4, and the output side positive electrode of the power source 7 steps up a heater voltage to a high voltage, rectifies and supplies it to the pump 6. And an evacuation by the pump 6 is performed via an evacuation port 17 which is bored in a metal cylinder 12. Thereby the degree of vacuum of the electron gun part is kept at a good enough level and the whole device can be simplified and be made compact.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Industrial Application Field) This invention relates to a microwave tube device, and in particular, the installation of an ion pump for maintaining the degree of vacuum during operation depends on the position and drive power supply. Concerning means.

(Prior art) Generally, a microwave tube device includes an electron gun section, an input waveguide section,
It consists of a high frequency acting part, an output waveguide part, a collector part, an ion pump, etc.

In such a microwave tube device, gas molecules generated from the electron gun section due to heating of the cathode and electron bombardment on the surface of each electrode pass through the drift tube to the microwaves in the high frequency acting section, collector section, and output waveguide section. Together with gas molecules generated from the wave output window, etc., the ion pump is evacuated by an ion pump attached to a vacuum envelope at ground potential, such as between the output waveguide section, collector section, and part of the body. The degree of vacuum within the electron gun section is maintained at a level that does not pose a problem for the operation of the cathode or the application of high voltage in vacuum.

Incidentally, among microwave tube devices, for example, pulse fighting klystrons and gyrotrons, there has recently been a demand for stably outputting larger microwave power at higher frequencies.

To achieve this, the electron gun must be capable of supplying a high-voltage, large-current electron beam, and as the cathode becomes larger, the amount of gas emitted increases, and a high degree of vacuum becomes necessary. There is. On the other hand, as wavelengths become shorter, the internal diameter of the drift tube must become smaller due to restrictions on the resonant frequency of the microwave resonator, resulting in a significant drop in exhaust conductance. For this reason, with the conventional method of exhausting the gas emitted from the electron gun via the drift tube, it is no longer possible to maintain the degree of vacuum inside the electron gun at a sufficiently good level, and these microwave tube devices , a pipe provided independently of a hollow part or a part of the body formed in a concentric cylindrical shape with the drift tube axis as the central axis is used as an exhaust path.

(Problems to be Solved by the Invention) In the configuration of the conventional microwave tube device as described above, the number of parts increases, the shape of the parts and the assembly process become complicated, which not only causes an increase in cost but also It has the disadvantage of causing defects. In addition, such an exhaust path needs to have a large cross-sectional area because it is necessary to increase the exhaust conductance, and the cutoff frequency for microwaves is lower than that of the drift tube. It may form a feedback path and cause oscillation.

Furthermore, since the outer diameter of a portion of the body becomes larger, the focusing electromagnet becomes larger, which increases not only the manufacturing cost but also the operating cost. This effect is particularly large in gyrotrons that use superconducting electromagnets.

SUMMARY OF THE INVENTION An object of the present invention is to provide a microwave tube device that maintains the degree of vacuum in the electron gun section at a sufficiently good level and solves the problems of the prior art.

[Structure of the Invention] (Means for Solving the Problems) In this invention, an ion pump for evacuation is attached to a heater terminal plate via a pipe, a high voltage power supply is provided near the ion pump, and the high voltage The power source is a microwave tube device configured to boost and rectify the heater voltage supplied to the heater terminal plate and supply it to the ion pump.

(Function) According to the present invention, gas molecules emitted from the electron gun section can be exhausted most effectively, and the degree of vacuum in the electron gun section can be maintained at a sufficiently good level. Furthermore, there is no need to take the trouble to introduce a power source to the ion pump from the outside, and the entire device can be simplified and made more compact.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

The microwave tube device according to the present invention is constructed as shown in FIG.
, an output waveguide section, and a collector section. However, the input waveguide section, output waveguide section, and collector section are omitted in the figure. A pair of heater terminal plates 3.4 are provided at the ends of the electron gun section 1, and an exhaust ion pump 6 is attached to the outer heater terminal plate 3 via a metal pipe 5.

Further, a high voltage power supply 7 housed in a box is provided near the ion pump 6, and the input side of the high voltage power supply 7 is connected to the heater terminal plate 4 via a lead wire 8. The positive electrode on the output side is connected to a positive electrode terminal 10 of the ion pump 6 via a Riet wire 9. In other words,
The high voltage power source 7 boosts and rectifies the heater voltage led from the heater terminal plate 3.4 through lead wires and pipes to a high voltage, and supplies it to the ion pump 6. For example, alternating current with a heater voltage of 6.3 to 10V is boosted and rectified into direct current of 3 to 4 kV by the high voltage power supply 7 and then supplied. Further, the cathode 11 of the electron gun section 1 is supported by a metal cylinder 12, and one end of a heater (not shown) for heating the cathode 11 is connected to the heater terminal plate 3 via a metal rod 13.
The other end is connected to the heater terminal plate 4 via the metal cylinder 12. In addition, the code 14 in the figure is an exhaust pipe, 1
5 is a permanent magnet, and 16 is a shield case made of magnetic metal. Evacuation by the ion pump 6 is performed through an exhaust port 17 bored in the metal cylinder 12. Such a microwave tube device is used by being housed in an insulating oil tank.

[Effects of the Invention] As explained above, according to the present invention, since the exhaust ion pump is attached to the heater terminal plate via a pipe, the gas molecules emitted from the electron gun are effectively pumped to the nearest point. This allows the electron gun to be evacuated to a sufficiently high level. In addition, a high voltage power supply is installed near the ion pump, and this high voltage power supply guides the voltage supplied to the heater terminal board, rectifies and boosts it, and supplies it to the ion pump. There is no need to introduce a power source, and the entire device can be simplified and made more compact.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a microwave tube device according to an embodiment of the present invention. 1...Electron gun section, 2...High frequency action section, 3.4...
・Heater terminal board, 6...Ion pump, 7...High 1
[E Voltage power supply. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] In a microwave tube device comprising an electron gun section, a high frequency acting section, and a collector section each having a heater terminal plate, an ion pump for evacuation is attached to the heater terminal plate via a pipe, and the ion pump is attached to the heater terminal plate through a pipe. A microwave tube device characterized in that a high voltage power source is provided near the pump, and the high voltage power source boosts and rectifies the heater voltage supplied to the heater terminal plate and supplies the same to the ion pump.