JPH02242550A - Cathode structure for magnetron - Google Patents

Abstract

PURPOSE:To reduce electric resistance by forming a passing through section for passing a stem ceramic of an external takeout lead in a round eye shape and terminal section in a hook shape with a sheet material. CONSTITUTION:A passing through section 10a for passing a stem ceramic 7 through and for insertion and connection to an intermediate member 8 is formed in a round eye shape. A reinforcement section 10b is mechanically reinforced by bending a flat plate. A terminal section 10c is connected by welding to a lead section of a filter circuit and formed as a hook in the shape of U or V. The external takeout lead 10 formed in this way, because of the round eye shape of the one end 10a, can be electrically connected to a center lead 4 and side lead 5 by inserting into the intermediate member 8 and soldering. The terminal section 10c on the other end, because of its planar shape, has excellent property of contact and welding with the lead section of the filter circuit. As a result, electric resistance at the connecting section is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cathode assembly for a magnetron, and particularly to an external lead.

[Conventional technology]

A magnetron for electronic voltage is configured to supply high voltage and large current to a cathode filament via a filter circuit that prevents high frequency noise generated in the magnetron body from flowing into general commercial conductive lines.

Therefore, the structure of the external lead for feeding power to the cathode filament is important for reliability, workability, and
This is important from the perspective of cost, etc.

FIG. 3 shows an example of the cathode structure of a conventional magnetron, in which 1 is a filament fixed and supported between an upper end shield 2 and a lower end shield 3 to prevent thermoelectrons from deviating in the tube axis direction. be done. The upper end shield 2 is fixed to the center lead 4, and the lower end shield 3 is fixed to the side leads 5 by brazing (copper-silver brazing), so that the center lead 4 passes through the through hole 3a of the lower end shield 3. (Japanese Patent Publication No. 60-55941, etc.).

Further, in the same figure, 6 is a sealing member, 7 is a stem ceramic whose one side 7a is metallized, and a set of relay members 8 are fixed to the metallized part by brazing, to which the center lead 4 and side 1- Insert and fix the cables 5 respectively. Reference numeral 9 denotes a pair of external leads, which are inserted into the relay member 8 through the through hole 7b of the stem ceramic 7 and fixed thereto.

In this way, the center lead 4 and the side leads 5 are electrically connected to the external lead 9 via the respective relay members 8, and the external lead 9 supplies high voltage and large current to the filament 1 from the power 1. That's what I do.

Here, the conventional external lead 9 often has a shape shown in FIG. 4 or FIG. 5, for example.

The external lead 9 shown in FIG. 4 is molded from a metal round bar as a raw material, and 9a is a terminal portion that connects the filter circuits and is molded into a hook shape.

This is a part into which a lead part of a filter circuit (not shown) is inserted and welded, and 9b is a penetrating part that penetrates the stem ceramic 8 shown in FIG. 3 and is inserted and connected to the relay member 8.

The external lead 9 shown in FIG. 5 is made from a metal round bar, and the terminal portion 9C that connects to the lead portion of the filter circuit is pressed into a plate shape, and then shaped into a hook shape. Then, if necessary, emboss the reinforcing part 9.
d is provided, and 9e is a through portion that is inserted into and connected to the relay member 8.

[Problem to be solved by the invention]

The conventional external lead 9 of the cathode assembly described above is all formed by processing and molding a round bar as a raw material.

That is, as shown in FIG. 4, the terminal part 9a connected to the lead part of the filter circuit is formed by simply bending a round bar into a hook shape, so that it has poor contactability and weldability with the lead part of the filter circuit. It is not suitable for large current power supply.

For example, in order to cause the filament 1 to emit light and cause the magnetron to perform the necessary operations, it is necessary to flow a high current of about 10 to 1.5 A through the filament 1.
In addition, in the exhaust process and carbonization process (process of carbonizing the surface of the filament) in the manufacturing process of the magnetron, it is necessary to flow a high current of about 10 to 15A through the filament 1. If the welding with the lead part is insufficient, the electrical resistance of that part will increase, and the necessary power will not be supplied, resulting in a force that cannot achieve the desired operation or process for the magnetron, or the connection part will be damaged. There is a risk that 9a may melt due to heating.

In addition, the one shown in Figure 5 involves partially pressing a round bar raw material into a flat plate, but the jig required for this pressing is relatively expensive and has a short lifespan, so it is difficult to manufacture. (Not preferred as it increases costs).

In view of the above problems, it is an object of the present invention to have an external lead that can be molded at relatively low cost, is suitable for power supply of high voltage and large current, and has good workability. An object of the present invention is to provide a cathode structure for a magnetron.

[Means to solve the problem]

” - The purpose of the description is to connect a filament disposed between an upper end shield and a lower end shield, a center lead fixed to the upper end shield and passing through a through hole in the lower end shield, and a center lead disposed between the upper end shield and the lower end shield, The side lead fixed to the end shield, the center lead and -1-
) A stem ceramic to which the idle leads are fixed via relay members, an external lead that penetrates the stem ceramic and is connected to each of the center lead and the side leads via the relay members, and is fixed to the stem ceramic. In the magnetron cathode assembly having a sealing member, the external extraction node is achieved by processing a plate material in which the penetration portion passing through the stem ceramic is rounded, and the terminal portion is formed into a hook shape. be done.

[Effect]

By the means described in F, the external lead can be connected to the center lead and the →F side via the conventional relay member, so this conventional connecting means can be applied as is. Furthermore, since the leakage part is formed into a plate shape, it has good contactability and weldability with the lead part of the filter circuit, and therefore has low electrical resistance and is suitable for large current applications.

In addition, since it is molded from a plate material, it has excellent workability and is easy to mechanically reinforce.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows an external extraction lead 10 according to the present invention, which corresponds to the conventional external extraction lead 9.
It is molded using a stainless steel plate material 11 having a shape as shown in FIG. 2 and having a thickness of approximately 0.3 mm.

Reference numeral 103 in FIG. 1 is a penetrating portion that penetrates the stem ceramic 7 of FIG. 1 and is inserted into and connected to the relay member 8, and is formed into a round shape.

In addition, 10b is a reinforcing part that mechanically reinforces the flat plate by bending it, and IOC is a terminal part that is welded and connected to the lead part of a fill circuit (not shown), which is formed into a hook shape such as a U-shape or 7-shape. be done.

The external lead 10 formed in this manner has one end 1. Since Oa is round, it can be connected electrically to the center lead 4 and the side lead 5 by inserting it through the relay member 8 and brazing it in the same manner as the connecting means for the external mounting lead 9 shown in can be connected.

In addition, since the terminal portion at the other end, the OC is plate-shaped, it has excellent contactability and weldability with the lead portion of the filter circuit, and therefore, the electrical resistance of the connection portion is low.

〔Effect of the invention〕

The external lead according to the present invention described above can be electrically connected to the center lead and the 4) side and 4) sides using the conventional relay member as is. It has excellent weldability with the lead part, improving welding workability. Furthermore, since the electrical resistance of the welded portion is low, it is effective for power supply of large currents.

In addition, since it is a plate material, it is easy to mechanically reinforce the flat part by bending, etc., and it is also economical because a low-profile plate material can be used and workability is good.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the external lead according to the present invention, FIG. 2 is a top view of the plate before forming the external lead shown in FIG. 1, and FIG. 4 and 5 are perspective views of a conventional external lead with a different husband. DESCRIPTION OF SYMBOLS 1... Filament, 2... Upper end shield, 3... Lower end shield, 3a... Through hole, 4... Center lead, 5... Side lead, 6... Seal member, 7... Stem ceramic, 8... Relay member, 10... External lead, 10a... Insertion part, 10c... Terminal part, tab... Reinforcement part, 11... Plate material. 320-

Claims (1)

[Claims] 1. A filament disposed between an upper end shield and a lower end shield, a center lead fixed to the upper end shield and passing through a through hole in the lower end shield, and a center lead fixed to the lower end shield. a stem ceramic that fixes the center lead and the side leads through a relay member, and an external body that penetrates the stem ceramic and is connected to each of the center lead and the side lead through the relay member. In a magnetron cathode assembly comprising a take-out lead and a sealing member fixed to the stem ceramic, the external take-out lead has a round penetrating portion passing through the stem ceramic, and a hook-shaped terminal portion. A cathode structure for a magnetron, characterized in that it is constructed from individually molded plate materials.