JP2664716B2 - Multi-cavity klystron - Google Patents

Description

The present invention relates to a multi-cavity klystron, and more particularly to a joint structure between drift tubes thereof.

(Prior Art) Conventionally, a multi-cavity klystron is configured as shown in FIG. 2, and a plurality of resonance cavities 1 are connected by a drift tube 2. In this case, drift tubes 2 are fixed to adjacent resonance cavities 1, and the outer ends of the cavities of the drift tubes 2 are joined via flanges 3 and 4, respectively. Welding flanges 5 and 6 are fixed to the flanges 3 and 4, respectively.
The two drift tubes 2 are hermetically joined. Incidentally, reference numeral 7 in the drawing denotes a support.

(Problems to be solved by the invention) In the conventional multi-cavity klystron as described above,
In operation, not only the operating frequency but also the high frequency component current is flowing through the electron beams gathered by the input cavity. A voltage is generated at the junction of the drift tube 2 by the current of the high-frequency component, and as a result, the operation of the klystron becomes unstable by modulating the electron beam. Also, if the contact of the drift tube 2 joint is incomplete,
The current is concentrated on the incomplete contact portion, and a vacuum leak occurs due to sparks, burnout, and damage to the flanges 3 and 4 and the welding flanges 5 and 6.

In the conventional multi-cavity klystron, the magnitude of the induced current was as small as several A to several tens A, and the problem was small.
The above-mentioned high-power multi-cavity klystron poses a problem because a large current of 500 A or more flows.

An object of the present invention is to solve the above-mentioned disadvantages and to provide a highly reliable and stable multi-cavity klystron.

[Constitution of the Invention] (Means for Solving the Problems) According to the present invention, a drift tube is fixed to adjacent resonance cavities, and the outer ends of the cavities of the drift tubes are respectively arranged in a lateral direction with respect to a tube axis. In a multi-cavity klystron airtightly joined via an enlarged flange, a gap of a predetermined dimension in the axial direction is formed between the two flanges, and the two flanges are matched at their outer peripheral edges so as to be airtightly joined. And a multi-cavity klystron in which each end on the electron beam passage side along the gap between both flanges is formed in a curved surface.

(Operation) According to the present invention, a highly reliable and stable multi-cavity klystron can be obtained.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

The main part of the multi-cavity klystron according to the present invention is as follows.
When the same portions as those in the conventional example (FIG. 2) are denoted by the same reference numerals, a plurality of resonance cavities 1
Are connected by In this case, drift tubes 2 are fixed to adjacent resonance cavities 1, and the outer ends of the cavities of the drift tubes 2 are joined via flanges 3 and 4, respectively. By forming a concave portion in at least one of the flanges, a gap 9 having a predetermined dimension in the axial direction is formed between the two flanges 3 and 4. That is, it is configured to have a structure capable of absorbing heat. Further, an end 10 on the electron beam path side along the gap 9 is formed in a curved surface.

The flanges 3 and 4 in such a state are hermetically joined at their outer peripheral edges by welding. That is, the weld 8
Except in the vicinity, the two flanges 3, 4 are not in contact. As described above, since the joints are formed only at the welded portions 8, there is no problem such as discharge due to current concentration. or,
Although a slight voltage is generated in the gap 9, the end 10 on the electron beam path side along the gap 9 is formed in a curved surface, so that concentration of the electric field is suppressed and no discharge occurs.

The diameter of the gap 9 is selected so that it hardly resonates at the operating frequency and its harmonic frequency. or,
Since the end 10 facing the electron beam path is formed as a curved surface, the generated high-frequency voltage is small, and the influence on the operation of the klystron can be reduced.

According to the present invention, a gap having a predetermined dimension in the axial direction is formed between both flanges of the drift tube, and the end on the electron beam path side along the gap is formed as a curved surface. A highly reliable and stable multi-cavity klystron can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a multi-cavity klystron of the present invention, and FIG. 2 is a longitudinal sectional view showing a conventional multi-cavity klystron. 1 ... Resonant cavity, 2 ... Drift tube, 3,4 ... Flange, 9 ... Gap, 10 ... End of the electron beam passage side.

Claims (1)

(57) [Claims] A drift tube is fixed to each of adjacent resonance cavities, and outer ends of the drift tubes are hermetically joined to each other via flanges which are expanded in the transverse direction with respect to the tube axis. In the multi-cavity klystron, a gap having a predetermined dimension in the axial direction is formed between the two flanges, and the two flanges are joined to each other at their outer peripheral edges to be air-tightly joined, and along the gap between the two flanges. A multi-cavity klystron, wherein each end on the electron beam path side is formed into a curved surface.