JPH0824030B2 - Magnetron - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron, and more particularly to a structure of an exhaust pipe support connected to an exhaust pipe.

[Background of the Invention]

A conventional magnetron has a structure as shown in FIGS. FIG. 1 shows before chip-off, and FIG. 2 shows after chip-off. That is, a vane 2 extending in the direction of the center is formed on the inner wall of the cylindrical anode 1, and a filament 3 made of thorium tungsten wire or the like is disposed at the center of the anode 1. The upper and lower ends of the filament 3 are fixed to upper and lower end shields 6 and 7 supported by the center and side supports 4 and 5, respectively. Also anode 1
Magnetic poles 8 and 9 each having a trapezoidal cross section are arranged at the upper and lower ends of the magnetic poles.

The structure of the output part is such that the seal part 10 disposed on the magnetic pole 8
Is fixed to the end surface of the anode 1, the exhaust pipe support 12 is fixed to the seal component 10 via the ceramic 11, and the exhaust pipe 13 is further fixed to the exhaust pipe support 12. An antenna 14 connected to one of the vanes 2 is arranged so as to extend inside the exhaust pipe 13.

The structure of the input portion is such that the seal component 15 disposed on the magnetic pole 9
Is fixed to the end surface of the anode 1, and the ceramic 16 is fixed to the sealing part 15. The center and side supports 4 and 5 pass through the ceramic 16, and the center and side supports 4 and 5 are fixed to the ceramic 16 via input terminals 17 and 18.

Therefore, in the magnetron configured as shown in FIG. 1, the exhaust pipe 13 is connected to a vacuum pump to degas the inside of the pipe. After the exhaust is completed, the exhaust pipe 13 and the antenna 14 are simultaneously turned off as shown in FIG. As a result, the degree of vacuum inside the tube is maintained.

By the way, since the exhaust pipe 13 is deformed at the time of tip-off, the deformation of the exhaust pipe 13 causes residual stress in the upper and lower brazing joints 19 and 20 of the exhaust pipe support 12, and the exhaust pipe support 12 is deformed. give. This brazed joint 19, 20
The residual stress and the deformation of the exhaust pipe support 12 increase as the chip-off height decreases and the height of the exhaust pipe support 12 decreases.

Recently, in order to miniaturize the magnetron, there is a tendency to lower the chip-off height and the height of the exhaust pipe support 12, but the lower the brazing joint 1 as described above.
The residual stresses of 9 and 20 and the deformation of the exhaust pipe support 12 become large, causing stress fracture in the brazed joints 19 and 20, which causes vacuum failure and fatal failure of the magnetron.

[Object of the Invention]

The object of the present invention is to reduce the residual stress of the brazing joint and the deformation of the exhaust pipe support that occur at the time of chip-off, improve the reliability of the brazing joint, and facilitate miniaturization. To provide a magnetron that can be achieved.

[Outline of Invention]

In order to achieve the above-mentioned object, the present invention is configured such that a high-frequency output section is sequentially connected by an exhaust pipe, an exhaust pipe support, a ceramic and a sealing component, and in a magnetron vacuum-sealed by these, a flat surface of the exhaust pipe support. It is characterized in that the portion is provided with an annular rib which is concave toward the sealing end of the exhaust pipe.

Example of Invention

An embodiment of the present invention will be described below with reference to FIG. It should be noted that the same or corresponding members as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. An annular rib 12a, which is concave toward the sealing end (chip-off portion) of the exhaust pipe 13, is provided on the flat surface portion of the exhaust pipe support 12.

As described above, since the exhaust pipe support 12 is provided with the rib 12a, the stress generated at the time of chip-off is
Not only reduces the residual stress of the brazed joints 19 and 20 and the deformation of the exhaust pipe support 12, but also the cross section of the rib 12a is the sealing end of the exhaust pipe 13 (chip-off portion).
Since it is concave toward, even if this rib 12a is provided,
Since neither the tip-off height of the exhaust pipe 13 (the dimension from the flat portion of the exhaust pipe support 12 to the tip-off portion) nor the height of the exhaust pipe support 12 needs to be larger than the conventional height, the magnetron is not required. The antenna height can be minimized and the magnetron can be easily miniaturized.

〔The invention's effect〕

As is clear from the above description, according to the present invention, the flat portion of the exhaust pipe support is provided with the annular rib that is concave toward the sealing end (chip-off portion) of the exhaust pipe. The residual stress of the brazing joint and the deformation of the exhaust pipe support at the time of chip-off are alleviated, the reliability of the brazing joint is improved, and even if ribs are provided, the tip-off height of the exhaust pipe and the exhaust pipe support Since it is not necessary to increase the height, miniaturization of the magnetron can be easily achieved.

[Brief description of drawings]

FIG. 1 is a sectional view of a conventional magnetron before chip-off,
FIG. 2 is a cross-sectional view of the magnetron of FIG. 1 after the chip-off, and FIG. 3 is a cross-sectional view of the magnetron of the present invention before the chip-off showing an embodiment of the magnetron. 10 …… Seal parts, 11 …… Ceramic, 12 …… Exhaust pipe support, 12a …… Rib, 13 …… Exhaust pipe.

Claims (1)

[Claims] 1. A high-frequency output part includes an exhaust pipe, an exhaust pipe support,
In a magnetron that is sequentially connected by a ceramic and a seal component and is vacuum-sealed by these, a concave annular ring-shaped rib toward the sealing end of the exhaust pipe is provided on a flat surface portion of the exhaust pipe support. A magnetron characterized by being provided.