JPH0719534B2 - Magnetron manufacturing method - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for manufacturing a magnetron, and more particularly to a method for assembling an anode assembly.

[Background of the Invention]

FIG. 1 is a longitudinal sectional view of an essential part showing an example of a magnetron anode assembly known from Japanese Utility Model Laid-Open No. 53-51169. In the figure, 1 is a cylindrical portion, 2 is a plurality of vanes forming a cavity resonator inside the cylindrical portion 1, and any one of the vanes 2 is an antenna for leading a microwave output to the outside. 3 is fixed. Numerals 4a and 4b are strappings for connecting a plurality of vanes 2 alternately and alternately for stable oscillation.

In such a configuration, as shown in FIG. 2, the method of fixing the antenna 3 to the vane 2 is as follows: the end of the antenna 3 is provided with a notch 3a having a width substantially equal to the plate thickness of the vane 2 and the vane 2. Is a notch 2a having a width substantially equal to the thickness of the antenna 3
And are fitted together to form a wire-shaped silver braze (usually a eutectic alloy of Ag: Cu = 72: 28 (weight ratio)) 5 as shown in FIG. The formed product is supplied as a so-called brazing solder as shown in FIG. 4, and the temperature is raised to about 850 ° C. in a non-oxidizing atmosphere such as hydrogen for silver brazing.

However, such an assembling method has the following problems. That is, (1) Since the silver solder 5 described above is handled as one assembled part, the accuracy required as an independent part is required particularly when the method such as automatic assembly is performed, and the supply method is also better than other parts. It is difficult to be small in size, which increases the number of assembly steps and makes automatic assembly extremely difficult.

(2) As for the brazing amount of silver braze 5, it is important that the brazing amount of the brazing braze 5 completely flows only to the portions where the notches 3a and 2a of the antenna 3 and the vane 2 are fitted to each other. In consideration of fluctuation (variation), a supply amount with a sufficient margin from the minimum required amount is required, so that the amount of expensive silver solder 5 used increases.

(3) Due to excess outflow of silver wax 5, strapping
A silver brazing material is generated in the vicinity of 4a and 4b, and the resonance characteristics are changed.

As for improving such a problem, as shown in FIGS.
As shown in the figure, it is conceivable to reduce the amount of silver braze 5 used by applying a silver plating 6 to the tip of the antenna 3 on the side where it is connected to the vane 2. Although the problem of 1) can be improved, (2),
The problem of (3) could not be improved sufficiently. Further, the silver plating 6 on the tip of the antenna 3 requires a completely different device from the mechanical assembling device, such as electric plating using acid, cleaning using water and drying with hot air. Since a special chemical that is highly corrosive is used, many inconvenient problems such as pollution prevention occur and the overall improvement effect is small.

[Object of the Invention]

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to easily assemble the anode assembly and reduce the amount of expensive brazing material used,
It is an object of the present invention to provide a method for manufacturing a magnetron that can obtain a magnetron with stable quality.

[Outline of Invention]

In order to achieve such an object, the method for producing a magnetron according to the present invention, the vane and the antenna are made of Cu material, and Ag powder to be a brazing material is previously plasma-sprayed above the notch of the vane side end of the antenna. Characterized by spraying to form an Ag-fixed body, and then combining the notch of the vane with the notch of the antenna to perform brazing in a reducing atmosphere and at a temperature lower than the melting points of both metals. And

Example of Invention

 Next, embodiments of the present invention will be described in detail with reference to the drawings.

7 and 8 are assembly process drawings of the anode assembly for explaining the embodiment of the magnetron manufacturing method according to the present invention, and the same parts as those in the above-mentioned drawings are designated by the same reference numerals. In these figures, first, FIG. 7 (a), (b)
As shown, before combining the antenna 3 made of Cu material and the vane 2 made of Cu material, Ag powder is fixed by plasma spraying above the notch 3a near the tip of the vane 2 side of the antenna 3. To form the Ag fixed body 7. Then this
The antenna 3 to which the Ag fixed body 7 is attached has the cutout portion 3a.
As shown in FIG. 8 in combination with the notch 2a of the vane 2 in a non-oxidizing atmosphere such as hydrogen and at the melting point (Ag
Melting point: 962 ℃, Cu melting point: 1083 ℃)
The Ag-fixed body 7 is melted by raising the temperature to 850 ° C., and is welded along the joint between the antenna 3 and the vane 2 to mechanically and electrically couple them.

According to such a method, since the Ag fixed body 7 in which the required amount of Ag powder is intensively sprayed by plasma spraying is formed above the notch 3a of the antenna 3, the use efficiency of the Ag brazing material is extremely high. The quality becomes stable and the excess Ag brazing material does not flow out, so that the quality can be stabilized. Further, since the plasma spraying of Ag powder can be easily performed in the supply path of the supply part of the antenna 3 of the automatic anode assembly apparatus, the configuration of the entire automatic assembly apparatus can be greatly simplified.

〔The invention's effect〕

As described above, according to the present invention, it is possible to save the amount of expensive silver used, prevent excess braze outflow, stabilize the characteristics, and facilitate automatic assembly. It has an extremely excellent effect that a magnetron of stable quality can be obtained with high productivity.

[Brief description of drawings]

1 to 6 are cross-sectional views of a conventional anode assembly and drawings for explaining a method of assembling the same, FIGS. 7 and 8.
The figure is a diagram for explaining an example of a method for manufacturing a magnetron according to the present invention. 1 ... Cylindrical part, 2 ... Vane, 2a ... Notch part, 3 ...
... antenna, 3a ... notch, 4a, 4b ... strap ring, 5 ... silver solder, 6 ... silver plating, 7 ... Ag fixed body.

Claims (1)

[Claims] 1. A plurality of vanes forming a cavity resonator,
In the method of manufacturing a magnetron comprising at least an antenna planted in any one of these vanes, the vane and the antenna are made of Cu material, and are provided above the notch portion of the vane side end portion of the antenna. The Ag powder to be a brazing material is previously sprayed by plasma spraying to form an Ag-fixed body, and then the notch of the vane is combined with the notch of the antenna in a reducing atmosphere, and the both metals are A method for producing a magnetron, which comprises brazing at a temperature of about 850 ° C. lower than the melting point of the magnetron.