JPH04286839A - Magnetron - Google Patents

Abstract

PURPOSE:To restrain the inner dia. of a vane from expansion and prevent electronic efficiency from lowering by radially arranging the anode vane inside of an anode cylinder and connecting the anode vanes for every other one via strap rings which are formed of material, smaller in thermal expansion coefficient than that for the vanes. CONSTITUTION:Even when the temperature at the tip of an anode vane 2 reaches 300-500 deg.C during magnetron operation, the inner dia. of the vane is restrained from expansion by a thermal expansion restraining layer 5 fitted to an inside strap ring 3 and an outside strap ring 4. Electronic efficiency is thus prevented from lowering, oscillation efficiency, stability and magnetron capability is free from lowering. The Cu layer 6 fitted to the inside and outside strap rings 3, 4 is provided to keep the inside and outside strap rings 3, 4 themselves from heat generation due to microwave loss and from breakage.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an anode structure for a magnetron.

0002

[Prior Art] Figure 2 shows the anode structure of a conventional magnetron (
FIG. In the figure, 1 is an anode cylinder, 2 is a plurality of anode vanes provided in the anode cylinder 1, and the anode vanes 2 are provided radially inward from the inner wall surface of the anode cylinder 1. 3 is an inner strap ring, 4 is an outer strap ring, and every other anode vane 2 is connected by the inner strap ring 3 and the outer strap ring 4.

0003

[Problems to be Solved by the Invention] In such a magnetron anode structure, when the magnetron is operating, the temperature at the tip of the anode vane 2 is 300 to 500°C.
, the inner diameter of the vane formed at the tip of the anode vane 2 increases due to thermal expansion of the anode vane 2. As a result, electronic efficiency decreases, so oscillation efficiency, stability, etc. decrease, and magnetron characteristics deteriorate.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide an anode structure for a magnetron in which the magnetron characteristics do not deteriorate.

[0005]

[Means for Solving the Problems] In order to achieve this object, the present invention provides a magnetron in which a plurality of anode vanes are arranged radially inside an anode cylinder, and every other anode vane is connected by a strap ring. In the anode structure, the strap ring is provided with a thermal expansion suppressing layer made of a material having a coefficient of thermal expansion smaller than that of the material of the anode vane.

[0006]

[Function] In this magnetron anode structure, when the magnetron is operating, the thermal expansion suppressing layer can suppress the vane inner diameter from increasing.
Electronic efficiency does not decrease.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a longitudinal sectional view of a magnetron. Figure 3
The same parts as in FIG. 2 are given the same numbers. Cathode 10
The electrons emitted from the permanent magnet 13 form a high-frequency potential in each anode vane while moving circularly under the influence of the DC magnetic field generated by the permanent magnet 13. This high frequency potential is emitted to the outside from the antenna 12 via the antenna lead 11.

FIG. 1 is a sectional view showing a strap ring of a magnetron anode structure according to the present invention. In the figure, 5 is a thermal expansion suppressing layer made of Fe, 6 is a Cu layer provided inside the thermal expansion suppressing layer 5, and the thermal expansion suppressing layer 5 and Cu
The inner strap ring 3 is bonded to the layer 6 by silver plating, and the thermal expansion suppressing layer 5 and the Cu layer 6 constitute the inner strap ring 3. Note that the outer strap ring 4 also has a similar configuration. In order to join the inner strap ring 3 and outer strap ring 4 to the anode vane 2, the thermal expansion suppressing layer 5 and the Cu layer 6 are fitted together and then silver plating is applied, or After the silver-plated thermal expansion suppressing layer 5 and the silver-plated Cu layer 6 are assembled into the anode vane 2, brazing is performed.
The thermal expansion suppressing layer 5 and the Cu layer 6 can be bonded together by silver plating, and the inner strap ring 3 and outer strap ring 4 can be bonded to the anode vane 2.

[0009] In this magnetron anode structure,
Even if the temperature at the tip of the anode vane 2 reaches 300 to 500°C while the magnetron is operating, the thermal expansion suppression layer 5 of the inner strap ring 3 and outer strap ring 4 prevents the inner diameter of the vane from increasing. Can be suppressed. As a result, it is possible to prevent the electron efficiency from decreasing, so that the oscillation efficiency, stability, etc. do not decrease, and the magnetron characteristics do not deteriorate. Also,
Since the inner strap ring 3 and the outer strap ring 4 have the Cu layer 6, the inner strap ring 3 and the outer strap ring 4 themselves do not generate heat due to microwave loss. 4 will not be damaged.

In the above embodiment, the thermal expansion suppressing layer 5 was provided on the outside of the inner strap ring 3 and the outer strap ring 4, but the thermal expansion suppressing layer 5 was provided on the inside of the inner strap ring 3 and the outer strap ring 4. It may be provided.

[0011]

[Effects of the Invention] As explained above, in the magnetron anode structure according to the present invention, the electronic efficiency does not decrease, so the oscillation efficiency, stability, etc. do not decrease, and the magnetron characteristics do not deteriorate. . As described above, the effects of this invention are remarkable.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a strap ring of an anode structure of a magnetron according to the present invention.

FIG. 2 is a diagram showing an anode structure of a conventional magnetron.

FIG. 3 is a longitudinal cross-sectional view of the magnetron.

[Explanation of symbols]

1...Anode cylinder 2...Anode vane 3...Inner strap ring 4...Outer strap ring 5...Thermal expansion suppression layer

Claims (1)

[Claims] 1. An anode structure for a magnetron, in which a plurality of anode vanes are arranged radially inside an anode cylinder, and every other anode vane is connected by a strap ring,
A magnetron characterized in that the strap ring has a thermal expansion suppressing layer made of a material having a smaller coefficient of thermal expansion than the material of the anode vane.