JPS6394536A - Magnetron cathode structure - Google Patents

Abstract

PURPOSE:To reduce the usage amount of Mo lead by arranging the sealing surface between an Mo lead and a stem ceramics to be on an inner end surface of a bulb of a stem ceramics, and the sealing surface between a sealing part and the stem ceramics to be on an outer end surface of a bulb of the stem ceramics. CONSTITUTION:A thermoelectron emitting filament 1 is placed between an upper end shield 2 and a lower end shield 3 to prevent deviation of thermoelectrons into an axial direction of a bulb, and a center lead 4 and a side lead 5 made of Mo are connected to the upper end shield 2 and the lower end shield 3, respectively. While the two leads 4 and 5 are brazed to an inner end surface of the bulb of a stem ceramics 6, a sealing part 7 is brazed to an outer end surface of the bulb of the stem ceramics 6. Accordingly, length of both leads 4 and 5 become substantially short and a distance between a fixed spot of the two leads 4 and 5 and the filament 1 is made short. By this method, vibration-proof and shock-proof characteristics of the filament 1 are substantially improved, which makes it possible to reduce wire diameters of the center lead 4 and the side lead 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetron cathode assembly, and more particularly to a magnetron cathode assembly in which the vibration resistance of a filament is improved and the material cost is significantly reduced.

[Conventional technology]

The conventional magnetron cathode structure was developed in 1975-1975.
As described in No. 9, the stem ceramics were disposed at the outer part of the sealing part to be hermetically sealed by brazing or the like.

However, no consideration has been given to reducing the cost of Mo materials by making the length of the lead using Mo or the like shorter than the surface of the seal component when brazing the seal component.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into consideration the amount of expensive Mo lead used, and has a problem in terms of cost.

An object of the present invention is to significantly reduce the amount of expensive Mo lead used without deteriorating the vibration resistance and impact resistance characteristics.

[Means for solving problems]

The first aspect is achieved by making the sealing surface between the Mo lead and the stem ceramic the inner end surface of the stem ceramic tube, and the sealing surface between the seal component and the stem ceramics the outer end surface of the stem ceramic tube.

[Effect]

The Mo lead has the role of supplying current to the filament and holding the carbonized brittle filament. here,
In order to hold the filament, the length of the Mo lead, which is the distance between the fixing point of the Mo lead and the filament, and
The wire diameter of the Mo lead is an important value.

By making the sealing part between the Mo lead and the stem ceramic the inner end surface of the stem ceramic tube, and the sealing part between the seal component and the stem ceramics the outer end surface of the stem ceramic tube, the fixing point of the Mo lead 6 is on the filament side. will come close to. As a result, the length of the Mo lead can be shortened, and the vibration resistance and WI impact resistance properties are also significantly improved, making it possible to make the Mo lead even thinner.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. In the figure 7, a filament 1 disposed at the center of the tube axis of the magnetron that emits thermionic electrons is protected by an upper end shield 2 and a lower end shield 3 that prevent thermionic electrons from deviating in the tube axis direction. It is clamped and the upper end shield 2
A center lead 4 and a side lead 5 made of MO are connected to the lower end shield 3, respectively.

Further, both of these leads are fixed to the inner end surface of the tube of the stem ceramics 6 by brazing, and a seal component 7 is further brazed to the outer end surface of the tube of the stem ceramics 6.

According to such a configuration, the lengths of both leads 4 and 5 are significantly shortened compared to conventional magnetron cathode structures, and the distance between the fixed portions of both leads 4 and 5 and the filament 1 is greatly shortened. Therefore, the vibration resistance and impact resistance characteristics of the filament 1 are greatly improved, the wire diameters of the center lead 4 and the side leads 5 can be made thinner, and the vibration resistance and impact resistance characteristics can also be improved.

〔Effect of the invention〕

According to the present invention, the lead made of expensive MO can be made short and thin, so it is inexpensive and has excellent vibration resistance and JftA characteristics.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a cathode structure of a magnetron showing an embodiment of the present invention. 1... Filament, 4... Center lead, 5...
・・Side lead, 6・Stem ceramics, 7・
・Seal parts. Agent: Patent Attorney Masaru Ogawa
・ 1st Figure 4, Centarit 5 size Idrid Otsu, Stemsera (・17 7: Sea 11 piece item)

Claims (1)

[Claims] 1. The upper and lower end shields fixed to the upper and lower ends of the filament that emits thermoelectrons have a center lead and a side lead connected to each other, and both leads are hermetically sealed to the stem ceramic. is a magnetron cathode structure formed by being hermetically sealed to a sealing part to constitute a magnetron tube, wherein the sealed portion between the leads and the stem ceramics is an inner end surface of the tube of the stem ceramics, and the stem ceramics and the stem ceramics are connected to each other. A magnetron cathode structure, characterized in that a sealed portion with a seal component is an outer end surface of the bulb of the stem ceramic.