JPH0754669B2 - Vane magnetron with pressure equalizing ring - Google Patents

Description

TECHNICAL FIELD The present invention relates to a magnetron as a cross field device, and more particularly to a vane magnetron with a pressure equalizing ring in which a plurality of anode pieces (vanes) are connected by a pressure equalizing ring. It is a thing.

[Prior Art] Conventionally, a vane type magnetron with a pressure equalizing ring is generally provided with a plurality of anode pieces extending radially from the inner surface of the anode cylinder 1 toward the center as shown in FIGS. 3 (A) and 3 (B). 2 to 19, inner pressure equalizing ring 20 and outer pressure equalizing ring 21 concentrically arranged on one surface side (front surface) of each anode piece 2 to 19, and concentrically arranged on the other surface side (rear surface). An inner pressure equalizing ring 22 and an outer pressure equalizing ring 23, and a front side inner pressure equalizing ring 20 and a back side outer pressure equalizing ring 23.
Is connected to every other anode piece 2,4,6,8,10,12,14,16,18 by brazing, and the outer pressure equalizing ring 21 on the front surface side and the inner pressure equalizing ring 22 on the back surface side remain. Anode piece 3,5,7,9,11,13,15,17,
It is connected to 19 by brazing. In addition, non-contact escape grooves (not shown) are formed in the anode pieces to which the pressure equalizing rings 20 to 23 are not connected.

Further, as another vane type magnetron with a pressure equalizing ring, as disclosed in JP-A-56-15534, three pressure equalizing rings having different diameters from the center of the anode cylinder are provided, and the center pressure equalizing rings are every other anode. It is known that the inner and outer pressure equalizing rings are connected to the remaining anode pieces.

[Problems to be Solved] However, each magnetron has the following problems.

Since the former magnetron has a structure in which the inner pressure equalizing rings 20 and 22 and the outer pressure equalizing rings 21 and 23 are provided on both surfaces of a plurality of anode pieces, it is extremely difficult to apply it to a high frequency magnetron. That is, the manufacturing method of the magnetron is as follows. First, the anode jig 1 and one of the pressure equalizing rings 22, 23 are used in the assembly jig.
After placing and positioning, place the anode piece 2 while matching the brazing surfaces.
-19 are sequentially inserted, and the other equalizing rings 20 and 21 are placed on the anode pieces 2 to 19 which are radially arranged. For example, in a magnetron with a frequency of 9.5 GHz, the thickness of the anode pieces 2 to 19 is increased. The size is 0.4 mm, the thickness of the pressure equalizing rings 20 and 23 on the front and back sides is 0.2 mm, and the higher the frequency of the magnetron, the smaller the anode cylinder 1, the anode pieces 2 to 19 and the pressure equalizing rings 20 and 23. Since the size must be small, the anode pieces 2 to 19 and pressure equalizing rings on both sides
Not only is it extremely difficult to match the brazed surfaces of 20 to 23, but high dimensional accuracy of the anode pieces 2 to 19 and the pressure equalizing rings 20 to 23 is required. In the case of the above 9.5 GHz magnetron, a high precision of ± 0.01 mm is required for each dimension, resulting in high manufacturing cost.

Since the latter magnetron has a structure in which three pressure equalizing rings are arranged on the anode piece, the brazing surface of the set of anode pieces connected to the central pressure equalizing ring is at one location, but the inner and outer pressure equalizing rings are There are two brazing surfaces of the set of anode pieces to be connected, and the number of brazing surfaces is different for different anode pieces. Therefore, there is a strong possibility that the anode pieces may be deformed due to the difference in thermal stress.

[Object of the Invention] The present invention solves the problems of the above-mentioned conventional examples, and an object of the present invention is that the anode piece can be manufactured by an easy manufacturing operation and there is no fear of deformation due to thermal stress of the anode piece. To provide a vane type magnetron with a pressure equalizing ring having a structure applicable to a high frequency magnetron.

[Means for Solving Problems] In order to achieve the above object, a vane magnetron with a pressure equalizing ring according to the present invention has an anode cylinder having a plurality of anode pieces extending in a radial direction toward the center, and one of the anode cylinders. Of four or more even pressure-equalizing rings arranged concentrically with respect to the center and having different diameters with respect to the center, and the odd-numbered pressure-equalizing rings from the center are connected to every other anode piece. In addition, the even pressure rings from the center are connected to the remaining anode pieces.

[Action]

 According to this structure, the following operational effects are obtained.

Since the equalizing ring is provided on only one side of the anode piece, it is much easier to assemble the magnetron than when there are equalizing rings on both sides of the anode piece. Assembling accuracy can be improved and a high frequency vane magnetron can be realized.

Since it has a structure in which four or more even pressure-equalizing rings are arranged on one side instead of two or three equalizing rings, the capacity load for frequency setting is distributed compared to the case of two or three. Therefore, the thickness (width) of the pressure equalizing ring can be reduced in the case of the same frequency. The anode piece has a strong temperature gradient because the center side (cathode side) has a high temperature and the anode cylinder side has a low temperature. Therefore, the inner side of the pressure-equalizing ring has much higher thermal expansion than the outer side. Since the frequency change of the magnetron is proportional to the width of the pressure equalizing ring, the inner pressure equalizing ring with large thermal expansion becomes dominant or dominant in the frequency change. In the present invention, since the width of the pressure equalizing ring on the inner side is small, it is possible to suppress the frequency change dominantly, and the pressure equalizing ring added to the outside is inferior to the frequency change and is also a very small width. As a result, and empirically, it is possible to significantly improve the temperature-dependent characteristics of the frequency change.

Since the surface side of the anode piece to which the pressure equalizing ring is connected is a restraining surface due to the pressure equalizing ring, the plurality of anode pieces extending in the radial direction from the anode cylinder flex toward the restraining surface side because the free surface side expands freely. The entire anode piece is in a state of bulging to one side like a drum skin. Here, every other positive electrode piece (first set) is connected to the innermost pressure equalizing ring and the outermost pressure equalizing ring, and the remaining positive electrode pieces (second set) are the second equalizing ring and the third from the inner side. If it is connected to the pressure equalizing ring of the first set, the connecting points of the first set of anode pieces are too far away from both ends, while they are too close to the center of the second set of anode pieces. Since the bending state is different between the anode pieces of the set and the anode pieces of the second set, variations occur in the frequency change. As in the present invention, when the first set of anode strips is connected to the first and third sides and the second set of anode strips is connected to the second and fourth sides, respectively, the first set of anode strips is also connected to the first set. Since the distribution of the connection points is similar in the two sets of anode pieces, the difference in the bending state between the first set of anode pieces and the second set of anode pieces is reduced, and variation in frequency change can be suppressed.

Since the connection points of each anode piece are equal at all even-numbered points, combined with the above advantages, thermal stress at high temperature tends to be equalized for any anode piece and pressure equalizing ring, and oscillation stability It is possible to realize a good magnetron.

[Embodiment] Next, an embodiment of a vane type magnetron with a pressure equalizing ring according to the present invention will be described with reference to the accompanying drawings.

1 (A) and 1 (B) are a plan view and a rear view showing an embodiment of a vane type magnetron with a pressure equalizing ring according to the present invention. The same parts as those shown in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted.

Inside the anode cylinder 1, a plurality of anode pieces 2 to 19 extending in the radial direction toward the center are provided. Multiple anode pieces 2-19
Have the same size and are radially arranged at equal angles. In this embodiment, the thickness of the anode pieces 2 to 19 is set to 0.4 mm in order to obtain a magnetron having a frequency of 9.5 GHz. Four pressure equalizing rings 30, 31, 32, 33 are provided on one surface (surface) of the anode pieces 2 to 19 which are radially arranged. Pressure equalizing ring 30-33
Have different diameters and are positioned concentrically with respect to the center of the anode cylinder 1 where the cathode (not shown) is located,
The 1st pressure equalizing ring 30 and the 3rd pressure equalizing ring 32 from the center are the anode pieces 2,4,6,8,10,12,14,16,18 (although every other one)
The second equalizing ring 31 and the fourth equalizing ring 33 from the center are connected to the other positive electrode pieces 3,5,7,9,11,13,15 by brazing. , 17, 19 (hereinafter referred to as the second set of anode pieces) are connected by brazing. In this embodiment, the pressure equalizing rings 30 to 33 have a thickness of 0.2 mm.

The first set of anode pieces to which the odd-numbered pressure equalizing rings 30 and 32 are connected have brazing step portions 30a and 32a to which the pressure equalizing rings 30 and 32 are fixed by brazing, as shown in FIG. 2 (A). Relief grooves 31b, 3 which should have no contact with the odd-numbered pressure equalizing rings 31, 33
Has 3b. Further, as shown in FIG. 2 (B), the second set of anode pieces has escape grooves 30b and 32b which should be in non-contact with the odd-numbered pressure equalizing rings 30 and 32. , 33
It has brazing step portions 31a and 33a.

In such a magnetron, the anode cylinder 1 is placed on an assembling jig, the anode pieces 2 to 19 are inserted while aligning the brazed surfaces and arranged radially. Created by placing ~ 33 concentrically.
In this manufacturing process, the four pressure equalizing rings 30 to 33 are carefully positioned on one surface of the anode pieces 2 to 19, so that the manufacturing can be facilitated as compared with the conventional method. Pressure equalizing ring 30
The frequency adjustment is performed by the capacitive load formed in the intervals of 33 to 33 and the clearances of the escape grooves 30b to 33b.
Since .about.33 are arranged on one side of the anode pieces 2 to 19, it is possible to successfully carry out the work of adjusting the intervals and gaps. Compared with the conventional case where pressure equalizing rings are arranged on both sides of the anode piece,
Since the capacity load is distributed by two pressure equalizing rings 30 to 33, the thickness of the pressure equalizing rings 30 to 33 can be reduced to about 0.2 mm as compared with the thickness of the anode piece, which contributes to the reduction of the supporting force of the anode piece. Furthermore,
Since there are two brazing surfaces on each of the anode pieces 2 to 19 with respect to the pressure-equalizing rings 30 to 33, the thermal stress is equalized in combination with the effect of reducing the supporting force described above, and thermal deformation of the pressure-equalizing rings 30 to 33 is effective. Can be prevented, and oscillation stability can be achieved.

In the above embodiment, four equalizing rings were arranged only on one side of the anode piece to form a high frequency magnetron, but an even number of equalizing rings of 4 or more (6,8,10 ...) Is provided on one side. It is also possible to construct a magnetron with a higher frequency by arranging them concentrically with each other.

[Effects of the Invention] As described above, in the vane-type magnetron with a pressure equalizing ring according to the present invention, while using four pressure equalizing rings, every other positive electrode piece (first set) has the innermost pressure equalizing ring and the other. Not only is it connected to the outer pressure equalizing ring, but the remaining anode pieces (second set) are not connected to the second pressure equalizing ring and the third pressure equalizing ring from the inside,
It is characterized in that every other positive electrode piece (first set) is connected to the odd-numbered pressure equalizing ring, and the remaining anode pieces (second set) are connected to the even-numbered equalizing ring. Therefore, the present invention has the following unique effects.

Since there is a structure in which four or more even pressure-equalizing rings are arranged on one side instead of two or three equalizing rings, the capacitive load for frequency setting is distributed compared to the case of two or three. Since the pressure equalizing ring can be made uniform, the thickness (width) of the pressure equalizing ring can be reduced in the case of the same frequency. Since the center side (cathode side) of the anode piece is hot and the anode cylinder side is cold,
Has a strong temperature gradient. Therefore, the inner side of the pressure-equalizing ring has a much larger thermal expansion than the outer side. Since the frequency change of the magnetron is proportional to the width of the pressure equalizing ring, the inner pressure equalizing ring with large thermal expansion becomes dominant in the frequency change. In the present invention, since the width of the pressure equalizing ring on the inner side is small, it is possible to suppress the frequency change dominantly, and the pressure equalizing ring added to the outside is inferior to the frequency change and is also a very small width. As a result, and empirically, it is possible to significantly improve the temperature-dependent characteristics of the frequency change.

Since the surface side of the anode piece to which the pressure equalizing ring is connected is a restraining surface due to the pressure equalizing ring, the plurality of anode pieces extending in the radial direction from the anode cylinder flex toward the restraining surface side because the free surface side expands freely. The anode piece as a whole bulges to one side like a drum skin. Here, every other positive electrode piece (first set) is connected to the innermost pressure equalizing ring and the outermost pressure equalizing ring, and the remaining positive electrode pieces (second set) are the second equalizing ring and the third from the inner side. If it is connected to the pressure equalizing ring of the first set, the connecting points of the first set of anode pieces are too far away from both ends, while they are too close to the center of the second set of anode pieces. Since the bending state is different between the anode pieces of the set and the anode pieces of the second set, variations occur in the frequency change. As in the present invention, when the first set of anode strips is connected to the first and third sides and the second set of anode strips is connected to the second and fourth sides, respectively, the first set of anode strips is also connected to the first set. Since the distribution of the connection points is similar in the two sets of anode pieces, the difference in the bending state between the first set of anode pieces and the second set of anode pieces is reduced, and variation in frequency change can be suppressed.

Since the connection points of each anode piece are equal at all even-numbered points, combined with the above advantages, thermal stress at high temperature tends to be equalized for any anode piece and pressure equalizing ring, and oscillation stability It is possible to realize a good magnetron.

[Brief description of drawings]

FIG. 1 (A) is a plan view showing an embodiment of a vane type magnetron with a pressure equalizing ring according to the present invention. FIG. 1 (B) is a rear view showing the same embodiment. FIG. 2A is a vertical cross-sectional view of the first set of anode pieces in the example. FIG. 2B is a vertical cross-sectional view of the second set of anode pieces in the same example. FIG. 3 (A) is a plan view showing an example of a conventional vane type magnetron with a pressure equalizing ring, and FIG. 3 (B) is a rear view thereof. 1 …… Anode cylinder, 2-19 …… Anode piece, 2,4,6,8,10,12,14,1
6,18 …… 1st set of anode pieces, 3,5,7,9,11,13,15,17,19 ……
Second set of anode strips, 30 ... first pressure equalizing ring, 31 ... second
Th pressure equalizing ring, 32 …… third pressure equalizing ring, 33 …… fourth pressure equalizing ring, 30a, 31a, 33a …… brazing step, 30b, 31b, 32
b, 33b ... Escape groove.

Claims (1)

[Claims] 1. An anode cylinder having a plurality of anode pieces extending in a radial direction toward a center, and four or more concentric circles arranged on one surface side of the anode cylinder and having different diameters with respect to the center. The above-mentioned even numbered pressure-equalizing rings are connected from the center to odd-numbered pressure-equalizing rings to every other positive electrode piece, and the even-numbered pressure-equalizing rings from the center are connected to the remaining positive electrode pieces. A vane type magnetron with a pressure equalizing ring.