JPH0778569A - Magnetron - Google Patents

Abstract

PURPOSE:To prevent peeling of getter material attached to an end shield completely by forming the getter material from a plate material, and integrating it with the end shield by rolling. CONSTITUTION:An end shield 6 is installed on a negative electrode support 4 through a boss 22 provided at the negative electrode support 4. The end shield 6 is formed by pressing a plate material. This plate material is an integral matter of No material disposed on the negative electrode filament 7 side and Ti material on it which are fixed to each other by rolling, and the Ti material has a function of a getter material 21. In this magnetron, the getter material 21 comprises the plate material, and it is integrated with the end shield 6 by rolling, so strong junction including molecular junction exists between the getter material 21 and the end shield 6 along the whole range of their boundary surfaces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron,
In particular, it relates to an improvement of the end shield for depositing the getter material.

[0002]

2. Description of the Related Art A magnetron is in an airtight state in which its inside is decompressed, and a so-called getter material is arranged in order to improve the degree of vacuum.
That is, the getter material has a function of absorbing the molecules of the gas released from each constituent member, and for example, zirconium (Zr) or the like is used as the material.

It is desirable to arrange such a getter material in a high temperature region in order to make its action effective. Conventionally, a getter material made of a plate material is used as an end shield for supporting a cathode filament. It was fixed by resistance welding.

[0004]

However, it has been pointed out that the magnetron having the above-mentioned structure has an adverse effect due to the getter material at the stage of its use.

That is, it is known that the getter material is deformed by absorbing gas, and therefore the periphery of the getter material is warped with respect to the end shield which is resistance-welded at several points. Aspect), it was found that the electric field is concentrated in this warped portion.

In the worst case, the getter material warps back, so that the getter material is completely peeled off from the end shield and falls off, not only having no function but also adversely affecting other components. There was an occasion.

The present invention has been made under such circumstances, and an object thereof is to provide a magnetron capable of completely preventing peeling of the getter material adhered to the end shield. Especially.

[0008]

In order to achieve such an object, according to the present invention, a getter material is basically attached to at least one of a pair of end shields supporting a cathode filament. In the present magnetron, the getter material is made of a plate material and is integrated with the end seal by rolling.

[0009]

[Operation] According to the magnetron thus constructed,
The getter material is a plate material and is integrated with the end shield by rolling.

With this structure, the getter material is firmly bonded to the end shield with a molecular bond over the entire boundary surface.

Therefore, even if the getter material has a property of being easily warped due to the absorption of gas molecules, the end portion of the getter material is warped against the end shield or is completely peeled off from the end shield. It will not happen.

Therefore, the getter material adhered to the end shield can be completely prevented from peeling off.

[0013]

FIG. 3 is a sectional view showing an embodiment of the magnetron according to the present invention.

In FIG. 1, first, there is a cathode portion 1, and the cathode portion 1 is an insulator 2 made of alumina ceramic,
Cathode supports 3 and 4 made of, for example, molybdenum or the like (high melting point metal) provided penetrating the insulator 2, and ends attached to the respective tip portions of the cathode supports 3 and 4 and facing each other. It is composed of shields 5 and 6 and a cathode filament 7 supported between the respective end shields 5 and 6.

A vane 8 is disposed around the cathode filament 7 and extending radially from the center.
Each of the vanes 8 is held by fixing its end face to the inner wall surface of the anode cylinder 9.
As a result, the vane 8 and the anode cylinder 9 constitute a so-called cavity resonator.

A cooling fin 10 is arranged on the outer peripheral portion of the anode cylinder 9 so as to abut the anode cylinder 9.

Magnetic poles 11 are arranged on both end surfaces of the anode cylinder 9, and the magnetic poles 11 are provided in the working space formed by the cathode filament 7 and the vane 8 with yokes 12 and 1.
An appropriate magnetic field is formed by guiding the magnetic flux from the magnets 14 and 15 cooperating with the magnet 3.

In this way, the microwave output generated at the cathode portion is radiated to the outside from the output section 17 through the output conductor 16 connected to one of the vanes 8.

The cathode supports 3 and 4 are the metal fittings 1.
Is airtightly brazed and fixed to the lower surface of the insulator 2 through
One end of the insulator 2 is brazed to a sealing metal body 19 welded and fixed to the anode cylinder 9 to maintain airtightness.

FIG. 2 is a configuration diagram showing details of the cathode portion of the magnetron.

The ends of the coiled cathode filament 7 are supported by end shields 5 and 6, respectively. The end shields 5 and 6 are supported by the cathode supports 3 and 4, respectively, and are arranged to face each other.

The end shield 5 is fixed to the tip portion of the cathode support 3, the end shield 6 penetrates the center portion of the end shield 5 (electrically insulated from the end shield 5), and the cathode filament 7 It is fixed to the tip of the cathode support 4 extending along the central axis.

FIG. 1 is an enlarged view showing details of the end shield 6 attached to the tip of the cathode support 4.

The end shield 6 in the figure is attached to the cathode support 4 via a boss 22 provided on the cathode support 4. The end shield 6 is fixed to the boss 22 by, for example, laser welding.

The end shield 6 is formed by pressing a plate material into a shape as shown in the figure. The plate material is made of titanium (Ti) on the upper surface of the molybdenum (Mo) material arranged on the cathode filament 7 side. ) It is a unitary product in which materials are fixed to each other by rolling. The titanium (Ti) material in this case has the function of the getter material 21.

In this case, the getter material 21 fixed to the upper surface of the molybdenum (Mo) material by rolling is titanium (Ti).
Of course, the material is not limited to zirconium (Zr) or tantalum (Ta).

Thus, the end shield 6 and the getter material 2 are
The one-piece plate material superposed with 1 is formed as shown by a punching press, for example, a larger one-piece plate material.

According to the magnetron constructed as in this embodiment, the getter material 21 is made of a plate material and is integrated with the end shield 6 by rolling.

From this fact, the getter material 21 is firmly bonded to the end shield 6 with a molecular bond over the entire boundary surface thereof.

Therefore, even if the getter material 21 has a property of being easily warped due to absorption of gas molecules, its end portion is warped against the end shield 6 or is completely separated from the end shield 6. It will not fall out.

Therefore, the getter material 21 adhered to the end shield 6 can be completely prevented from peeling off.

Further, by doing so, since the end shield 6 and the getter material 21 can be formed at the same time, there is an effect that the number of processing steps can be greatly reduced.

Further, the getter material 21 is the end shield 6
Since it is fixed to the entire surface, heat from the cathode filament 7 can be efficiently conducted to the getter material 21 via the end shield 6. Therefore, the gas molecule absorbing ability of the getter material 21 can be significantly improved.

Further, since the surface area of the getter material 21 can be made the same as that of the end shield 6, it can be made larger than the conventional one.
It becomes possible to improve the gas molecule absorption capacity of the above-mentioned method compared with the conventional case.

[0035]

As is apparent from the above description,
According to the magnetron of the present invention, the getter material deposited on the end shield can be completely prevented from peeling off.

[Brief description of drawings]

FIG. 1 is a configuration diagram in the vicinity of a getter material showing an embodiment of a magnetron according to the present invention.

FIG. 2 is a configuration diagram in the vicinity of a cathode part showing an embodiment of a magnetron according to the present invention.

FIG. 3 is an overall configuration diagram showing an embodiment of a magnetron according to the present invention.

[Explanation of symbols]

 3,4 Cathode support 5,6 End shield 7 Cathode filament 21 Getter material

Claims (1)

[Claims] 1. A magnetron in which a getter material is applied to at least one of a pair of end shields supporting a cathode filament, wherein the getter material is a plate material and is integrated with the end shield by rolling. It is a magnetron that is characterized by.