JPH07109752B2 - Magnetron - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a magnetron anode assembly in which a plurality of combined strap rings have the same shape and size.

[Background of the Invention]

The structure of the magnetron anode assembly that has been widely used in the past is
FIG. 1 (a) is a plan view, and FIG. 1 (b) is A- in FIG.
As shown in the sectional view taken along the line A ', even number of vanes radially arranged from the cylindrical portion 1a of the anode 1 toward the center of the cylinder are electrically connected by the strap rings 3 and 4 every other sheet. .

The anode 1 is manufactured by hobbing an oxygen-free copper billet to integrally form the cylindrical portion 1a and the vanes 2, and then embedding a resin or the like between the vanes 2 and lathe-forming the same. As shown in, grooves 2a having a substantially rectangular cross section are provided at the upper and lower ends of the cylinder in the axial direction. After such finishing, the resin is removed.

On the other hand, the strap rings 3 and 4 are formed by press-punching an oxygen-free copper plate or the like to form an inner strap ring 3 and an outer strap ring 4 having different diameters. Then, these strap rings 3 and 4 should be plated with silver, and the projections 3a and 4a of the strap rings 3 and 4 should be driven into the groove 2a of the vane 2 with a slight tightening allowance, or fitted slightly. Place it with a gap and caulk the inner strap ring 3 with the taper punch 10 shown by the dotted line from the direction of the arrow C, and caulk the outer strap ring 4 with the wedge punch 11 shown by the dotted line from the direction of the arrow C'to give a reducing atmosphere of about 800 ° C. A silver brazing layer is formed in the furnace by the silver plating layer and the copper material to securely braze and fix.

Further, FIG. 2 shows a so-called brazing type magnetron anode structure in which the cylinder 1a and the vane 20 are separately brazed by using an assembling jig (not shown).

In this anode structure, as is apparent from the drawing, the strap rings 30 and 40 do not require the protrusions 3a and 4a as shown in FIG.
As shown in FIG. 2B, it is necessary to change the groove 20a to which the inner strap ring 30 is connected and the outer strap ring 40 which is connected due to the difference in their diameters.

In these anode structures, the oscillating frequency of the magnetron is determined by the capacitances and inductances formed by the vanes, the capacitances formed by the strap rings 3,30,4,40 and the grooves 2a, 20a, and the strap rings. The capacitance and the like function as main elements and are determined, and the fine adjustment of the oscillation frequency is performed by varying the capacitance between the strap rings 3, 30, 4, 40 and the grooves 2a, 20a. Therefore, when correcting the deviation from the frequency to be set in the assembled anode structure, the facing areas of the grooves 2a, 20a and the strap rings 3, 30, 4, 40 are smaller than the facing areas of the strap rings. It becomes necessary to take a large amount of deformation of the strap ring for correction. These will increase the potential for abnormal approach when modifying.

In addition, the stress due to the strain of the trapping generated by the stretching strap and the vane protruding in the direction of the central axis during the operation accompanying the ON / OFF movement of the magnetron causes the inner strapping with the smaller diameter than the outer strap with the larger diameter. Since the distance between the connection points is smaller, the number becomes larger, and damage to the strap ring due to the life test of the magnetron is more likely to occur in the inner strap ring.

[Object of the Invention]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetron anode assembly having a plurality of strap rings whose ring parts have the same dimensions and which are improved in assemblability and reliability.

[Outline of Invention]

The conventional plurality of strap rings that constitute the anode of the magnetron have different diameters inside and outside the mounting groove. The present invention enables a plurality of strap rings to have the same shape and the same size by changing the arrangement direction of the strap rings, which improves the assemblability and the reliability in the manufacturing process. Is.

Embodiment of the Invention FIG. 3 (a) is a plan view of an embodiment of the present invention,
(B) shows the CC ′ line sectional view in (a). Reference numeral 31 is an inner strap ring according to the present invention, 41 is an outer strap ring according to the present invention, and other symbols are the same as in the conventional case. In the anode assembly shown in FIG. 3, the dimensional relationship between the strap rings 31, 41 and the groove 21a of the vane 21 is a combination with a slight caulking margin. Since the outer strap ring 41 and the outer strap ring 41 are sequentially assembled by forced press fitting, the groove 21a may have a simple rectangular shape.

FIG. 4 is a view showing another embodiment of the present invention. In the anode structure shown in FIG. 4 (b), the groove 22a of the vane and the strap rings 32, 42 each have a slight fitting margin (gap). Due to the dimensional relationship, a small step is provided in the groove 22a so that the groove 22a can be assembled. In this case, the inner strap ring 32 and the outer strap ring 42 can be simultaneously caulked by pressing the vane 22 with the taper punch 10 shown by the dotted line from the direction of the arrow C.

That is, in the case of the embodiment shown in FIG.
The outer ring 31 and the outer strap ring 41 can be assembled in exactly the same size. Even in the embodiment of FIG. 4, the width dimension of the fitting portion of the vane 22 into the groove 22a is slightly different, but the ring of the strap ring Since the portion can be made the same as the inner and outer strapping portions, the stress generated in the strapping due to the operation of the magnetron described above is the same as in the embodiment of FIG. Things will disappear. Moreover, in the conventional cross-sectional shape of the ring portion of the strap ring, the axial thickness is larger than the radial thickness in the present invention,
Contrary to the conventional one, the thickness in the axial direction is made smaller, so that the rigidity of the strap ring against thermal stress can be remarkably increased.

Furthermore, in the strap ring of the present invention, since the relative area between the inner and outer strap rings is large, the capacitance thereof is larger than the capacitance formed by the strap ring and the groove, and only the outer strap rings 40 and 41 are formed. The oscillation frequency can be easily adjusted by moving in the axial direction. Further, since the strap ring according to the present invention is formed by stamping and punching a plate material, it is possible to easily obtain a high precision one as compared with the conventional one.

〔The invention's effect〕

As described above, according to the present invention, it is possible to obtain a strap ring which is resistant to the heat stress generated by the magnetron operation, has high reliability, has high processing accuracy, and is excellent in assemblability.

[Brief description of drawings]

FIG. 1A is a plan view of a conventional magnetron anode assembly, FIG. 1B is a sectional view taken along the line AA ′ in FIG. 2A, and FIG. 2A is another conventional magnetron anode assembly. An example plan view, (b) is a sectional view taken along the line BB 'in (a), (a) of FIG. FIG. 4A is a sectional view taken along line C ′, FIG. 4A is a plan view of another embodiment of the present invention, and FIG. 4B is a sectional view taken along line DD ′ in FIG. 1 ... Anode, 1a ... Cylindrical part, 2,20,21,22 ... Bain, 2
a, 20a, 21a, 22a …… groove, 3,30,31,32 …… inner strap ring, 4,40,41,42 …… outer strap ring.

Claims (1)

[Claims] 1. An anode cylinder constituting a cavity resonator and an even number of vanes radially arranged therein, wherein a groove having a generally rectangular cross section is formed at a part of an end portion of the vane in the axial direction of the cylinder. In a magnetron having a pair of strap rings for electrically connecting in the groove with every other one of the vanes, the pair of strap rings have a plate shape having the same shape and the same size. A magnetron arranged in the groove at a predetermined interval in the axial direction of the vane, and a strap ring is fixed to each of the grooves on both inner and outer sides in the radial direction.