RU2579430C2 - Cathode preheating unit - Google Patents

Abstract

FIELD: electronic equipment.

SUBSTANCE: invention relates to the field of electronic engineering. Cathode preheating unit for powerful klystron cathode contains several separate modules of a given size, each of which consists of a cathode block elementary cathode heater, holder, screen and are coaxially arranged drift tube klystron. Part of the cathode of each module to a height of (0.2-2.0) mm from the end opposite the working - emitting - a surface formed with a diameter greater than the diameter of the cathode module (0.2-10.0) mm. Warming cathode assembly is further provided with two cylinders - external and internal, with a given diameter, height - external, equal to the height of the cathode a separate module, or no more than two of its height, the inner - equal to the height of the cathode module, or - at least 0.5 of its height Each wall thickness (0.3-0.8) mm, the cylinders are arranged coaxially one inside the other in the working plane - emitting - cathode surface modules. Each individual cathode unit is additionally provided with a separate cylinder placed therein with a gap and secured by said holder part, with a separate barrel is diameter, which mate of cathode modules, height, at the height of the cathode module (1.0-5.0) mm, with a wall thickness equal to (0.2-0.6) mm, at the outer end face of each cylinder in the plane of the working - emitting - a surface formed monolithically fastening elements, each in the form of a circular segment with the length of its curve (4.0-8.0) the wall thickness of the individual cylinders in multiples of four and the individual cylinders with individual cathode modules are disposed between the inner and outer cylinders.

EFFECT: technical result - increase durability, power output and efficiency.

5 cl, 1 dwg, 1 tbl

Description

The invention relates to electronic equipment, namely to cathode-heating units for high-power microwave devices, in particular klystrons.

One of the main tasks today is the creation of powerful and heavy-duty multi-tube klystrons.

Distinguish single-beam and multi-beam klystrons.

Multipath amplification klystrons (klystrons) are the basis of transmitters of modern perspective airborne, marine and ground electronic systems.

Recently, multi-tube klystrons have become known, which are two or more partial multi-beam klystrons, combined by a single vacuum shell and a single input and output of energy.

The cathode assembly emitting electrons is one of the main elements of any type of klystron.

One of the main characteristics of the cathode assembly for high-power multipath klystrons is a high uniform level of emission of all emitting surfaces, providing high and stable parameters of the klystron.

Powerful or heavy duty klystrons based on multi-beam electron-optical systems are known, implemented by summing a multi-beam klystron, consisting of eight groups of eight rays in each, in which eight separate cathode-heating units are used, placed on a common basis [1].

These klystrons are powerful (up to 100 kW) or heavy duty (more than 100 kW).

However, these klystrons are not very durable and unstable due to

firstly, the non-identity of the geometric dimensions of the individual bases of the individual cathode-heating units,

secondly, the non-identity of the geometric dimensions of the individual bases of the individual cathode-heating units and the system of elements - mesh, anode, resonator block klystron, the elements of which are made in one piece,

thirdly, the variation in the operating temperature of individual cathode-heating units.

This determines the low durability and low stability of individual cathode-heating units and, accordingly, klystron.

Moreover, this klystron design is difficult to implement.

Known cathode-heating unit for a powerful klystron, containing two separate cathode modules, each of which consists of a cathode block of elementary cathodes, a heater, a holder and which end faces opposite to the ends with a working - emitting - surface are located on one separate base made of refractory material and at the same time coaxially to the klystron span tubes [2] - prototype.

This design due to the specified arrangement of elements (two-pipe) allowed to significantly increase the number of rays of the klystron and, accordingly, its output power in pulsed mode.

However, the above disadvantages of the analogue as a whole remained, namely, the non-identity of the geometric dimensions of the individual bases of the individual cathode-heating units, the non-identity of the geometric dimensions of the individual bases of the individual cathode-heating units and the system of elements — the grid, the anode, the resonator block of the klystron, the elements of which are made in one piece, the spread operating temperature of individual cathode-heating units.

Moreover, the presence of butt welds at a significant linear distance from the working - emitting - surface when the cathode is heated to a working temperature (~ 1100 ° C) additionally leads to a change in the initially set geometric dimensions.

This determines, as in the analogue, the low durability of the cathode-heating unit and, accordingly, the restrictions on the output power in pulsed mode and the efficiency of a powerful klystron.

The technical result of the claimed invention is to increase the durability of the cathode-heating unit by increasing the identity of the geometric dimensions of its elements and reducing the variation in the operating temperature of individual cathode-heating units, reducing the weight and size characteristics and, accordingly, increasing the output power, efficiency, expanding the functionality of a powerful klystron.

The technical result is achieved by a cathode-heating unit for a powerful klystron, containing several individual cathode modules of a given size, each of which consists of a cathode block of elementary cathodes, a heater, a holder, a screen and which are aligned with the klystron span tubes, in which

the cathode-heating unit contains individual cathode modules that are multiples of four,

part of the holder of each individual cathode module to a height of (0.2-2.0) mm from the end opposite the working - emitting - surface is made with a diameter exceeding the diameter of the cathode module by (0.2-10.0) mm,

the cathode-heating unit is additionally equipped with two cylinders - external and internal, with given diameters, respectively, height - external, equal to the height of an individual cathode module or not more than two of its heights, internal - equal to the height of the cathode module or not less than 0.5 of its height, each with a wall thickness of (0.3-0.8) mm, while the cylinders are coaxially located one in the other in the plane of the working - emitting - surface of the cathode modules,

each individual cathode module is additionally equipped with a separate cylinder, placed therein with a gap and secured by the aforementioned part of the holder, while a separate cylinder is made with a diameter that ensures the coupling of all cathode modules with a height less than the height of the cathode module by (1.0-5.0) mm, with a wall thickness equal to (0.2-0.6) mm, on the outer surface of the end face of each individual cylinder in the plane of the working - emitting - surface, the mounting elements are made integral, each in the form of a circular segment, with length e about the curve (4.0-8.0) from the wall thickness of an individual cylinder, in an amount multiple of four,

and individual cylinders with separate cathode modules are located between the outer and inner cylinders to ensure that the ends of each individual cylinder are aligned in the same plane with the individual cathode modules with fasteners and ends of the outer and inner cylinders and are fixed to each other by fasteners at contact points that are multiples of four, the specified diameters of the outer and inner cylinders, the diameter of the exceeding part of the holder are determined from the expressions, respectively

Dext.c = Dc.pr.pipe + Ddec. cylinder.km.

Dvts.ts = Dts.pr.pipe-Dotd. cylindrical km.

Dpr.h.d. = Ddend cylinder.km.-2 × S, where

Dts.pr.pipe - the diameter of the location of the centers of the passage pipes of the klystron, mm,

Dotd. cyl.km - the diameter of the individual cylinder of the cathode module, mm,

S is the wall thickness of the individual cylinder of the cathode module, mm, and all of the mentioned elements are made of refractory material.

The specified dimensions of the individual cathode modules are determined by the technical characteristics of the klystron.

A separate cylinder of each individual cathode module is monolithic with fastening elements on the outer surface of the end face in terms of the plane of the location of its working - emitting - surface made, for example, by stamping and electric spark processing, respectively.

Separate cylinders with separate cathode modules located between the outer and inner cylinders are fixed to each other by fastening elements at the contact points that are multiples of four, for example, by welding.

Refractory material can be molybdenum, tantalum.

The outer and inner cylinders can be made with stiffeners.

Disclosure of the invention

The set of essential features of the claimed cathode-heating unit for a powerful klystron, namely when:

part of the holder of each individual cathode module to a height of (0.2-2.0) mm from the end of the opposite working - emitting - surface is made with a diameter exceeding the diameter of the cathode module by (0.2-10.0) mm,

The cathode-heating unit is additionally equipped with two cylinders - external and internal, with predetermined diameters, height - external, equal to the height of an individual cathode module or not more than two of its heights, internal - equal to the height of the cathode module or not less than 0.5 of its height, each with wall thickness (0.3-0.8) mm, while the cylinders are coaxially located one in the other in the plane of the working - emitting - surface of the cathode modules,

each individual cathode module is additionally equipped with a separate cylinder, placed therein with a gap and secured by the aforementioned part of the holder, while a separate cylinder is made with a diameter that ensures the coupling of all cathode modules with a height less than the height of the cathode module by (1.0-5.0) mm, with a wall thickness equal to (0.2-0.6) mm,

on the outer surface of the end face of each individual cylinder in the plane of the working - emitting - surface, the mounting elements are made in one piece, each in the form of a circular segment, with a length of its curve (4.0-8.0) from the wall thickness of an individual cylinder, in an amount multiple of four ,

and individual cylinders with separate cathode modules are located between the outer and inner cylinders to ensure that the ends of each individual cylinder are aligned in the same plane with the individual cathode modules with fasteners and ends of the outer and inner cylinders and are fixed to each other by fasteners at the contact points that are multiples of four.

This will provide:

rigidity without landing gaps of the elements of the cathode-heating unit both in the individual cylinder and when they are subsequently planted in the cathode module, and thereby the stability of their geometric dimensions, and thereby the maximum alignment of the location of the individual cylinders with the individual cathode modules relative to the klystron span tubes,

reliable monolithic connection without gaps of the elements of the cathode-heating unit and thereby the maximum sufficient strength of all its elements,

almost complete exclusion of the temperature difference between the working - emitting - surface and the external and internal cylinders and thereby - the maximum stabilization of the thermal field in the region of the working - emitting - surface.

the ability to shield non-working - emitting surface areas and thereby further stabilizing the thermal field in the area of the working - emitting surface,

the possibility of a significant increase in the composition of the emitting elements of the klystron up to 64-ray klystron and more,

the ability to work both in pulsed and continuous mode.

And as a consequence: -

firstly, increasing the durability of the cathode-heating unit and, accordingly, a powerful klystron,

secondly, a significant increase in the output power and efficiency of the klystron,

thirdly, a decrease in the overall dimensions of the cathode-heating unit and, accordingly, a powerful klystron,

fourthly, the expansion of the functionality of a powerful klystron.

The determination of the specified diameters of the outer and inner cylinders according to the specified mathematical expressions ensures the optimal dimensions of the structural elements of the cathode-heating unit and thereby the maximum phase synchronization of the klystron and, as a result, an increase in the output power and efficiency of a powerful klystron.

The implementation of the holder part of each individual cathode module with a larger diameter at a specified height is optimal for subsequent connection with a separate cylinder from the point of view of optimal structural design.

The implementation of the cathode module with an excess of the diameter from the end opposite to the working - emitting - surface, both less than 0.2 mm and more than 10.0 mm is unacceptable due to the violation of the heat balance.

The implementation of an external cylinder with a height less than the height of a single cathode module is unacceptable due to the deterioration of its screening, and more than two of its heights does not make sense.

The implementation of the inner cylinder with a height of less than 0.5 of the height of the cathode module is not desirable due to the decrease in structural rigidity, and more - its height does not make sense.

The execution of the outer and inner cylinders of each with a wall thickness of less than 0.3 mm is unacceptable due to violation of the rigidity and reliability of the structure, and more than 0.8 mm does not make sense.

The execution of a separate cylinder with a height lower than the height of the cathode module by 1.0 mm or 5.0 mm is unacceptable, in the first case due to the occurrence of electrical breakdown, in the second - due to a violation of the heat balance.

The implementation of a separate cylinder with a wall thickness of less than 0.2 or more than 0.6 mm is not desirable, in the first case due to a violation of stiffness, in the second because of a violation of the plasticity of the fastening elements and, consequently, difficulties in the subsequent connection.

The implementation of the fastening elements in an amount less than a multiple of four, in the form of a circular segment, with a curve length of less than 4.0, more than 8.0 of the wall thickness of an individual cylinder is unacceptable,

in the first case due to the lack of contact points, in the second because of a possible violation of the design of the fastening elements.

The invention is illustrated in the drawing.

In FIG. a particular case of the claimed cathode-heating unit for a powerful 64-beam klystron is given, a general view with a cut-out (Fig. 1a), a general sectional view (Fig. 1b), a top view (Fig. 1c), and where:

- a separate cathode module - 1,

- cathode block of elementary cathodes - 2,

- heater - 3,

- holder - 4,

- screen - 5

- the location of the centers of the passage pipes klystron - 6,

- two cylinders, external - 7, internal - 8,

- a separate cylinder of each individual module - 9 with integral elements of fastening 10.

Examples of specific performance of the claimed module of the cathode-heating unit for powerful klystrons.

Example 1. A special case of the implementation of the claimed cathode-heating unit for a powerful 64-beam klystron is considered (Fig. 1a, b, c).

The technical requirements of the powerful 64-beam klystron are set by:

The diameter of the arrangement of the centers of the passage pipes of the klystron 6, equal to 60.0 mm,

The diameter of the individual cathode module 1, equal to 17.0 mm.

The height of the individual cathode module 1, equal to 18.0 mm

The wall thickness of the individual cylinder of the cathode module 9, equal to 0.4 mm

Determine:

The diameter of the individual cylinder 9 of each individual module 1 is determined, which ensures the coupling of all cathode modules.

Dot.ts.k.m. equal to 23 mm, which corresponds to the distance between the centers of two mating span pipes.

The diameter of the outer 7 and inner 8 additional cylinders based on the diameter of the centers of the span tubes of the klystron 6.

Dext.c = Dc.sp.tube + Ddec. Cylinder = 60 + 23 = 83 mm

Inner = Dts.pr.pipe -Dot.dr. cylinder = 60-23 = 37 mm

The diameter of the greater part of the holder 4 of the cathode module.

Dpro.ch.d. = Dde. cyl.km.-2 × S = 23- (2 × 0.4) = 22.2

(According to the mathematical expressions indicated in the claims, respectively).

Two cylinders are made - outer 7 and inner 8 with diameters of 83.0 mm and 37.0 mm, respectively, each with a wall thickness of 0.6 mm, a height of 27.0 mm and 13.5 mm, respectively, from a sheet of refractory material - tantalum TU647RKZ 0054230 -311-2000 (hereinafter referred to as tantalum) by stamping and placed coaxially in one another in the plane of the working - emitting surface of the cathode modules 1.

A holder 4 is made of tantalum. Part of the holder of each individual cathode module to a height of 1.1 mm from the end opposite to the working - emitting - surface is 22.2 mm in diameter (5.2 mm in excess of the diameter).

Separate cylinders 9 are made in the amount of eight pieces of tantalum, 23 mm in diameter, 14.0 mm high (commensurate with the individual cathode module 1, while the height of the individual cathode modules is determined by the mass and size characteristics of the klystron), with a wall thickness of 0.4 mm by stamping.

On the outer surface of the end face of each individual cylinder 9 in the plane of the working - emitting - surface, the fastening elements 10 are made integral, each in the form of a circular segment, with a curve length of 2.4 mm (which corresponds to 6.0 from the wall thickness of an individual cylinder - 0, 4 mm), in an amount that is a multiple of four, by the method of electrospark processing on a machine like ARTA122.

Separate cylinders 9 with separate cathode modules 1 are positioned between the outer 7 and inner 8 cylinders to ensure that the ends of each individual cylinder 9 are aligned in the same plane with the individual cathode modules 1 with fasteners 10 and the ends of the outer and inner cylinders 7 and 8 and are fixed together laser landing by means of fastening elements 10 at contact points that are multiples of four (8 × 4) by laser welding (Type Nd: YAG).

Examples 2-5. Analogously to example 1, samples of the cathode-heating unit for a powerful 64 multi-beam klystron were made, but with other design parameters specified in the claims (examples 2-3) and beyond the limits specified in the claims (examples 4-5).

Example 6 - corresponds to the design of the cathode-heating unit of the prototype used in a 30-beam klystron.

The manufactured samples of the modules of the cathode-heating unit were tested in the powerful 64-beam klystron indicated above.

In this case, the output power was measured in a pulsed mode (GOST 2027.1-91).

Durability (RD 11.0770-90).

Efficiency determined.

The data are presented in the table.

As can be seen from the table, the output power in pulsed mode of a powerful klystron with samples of the cathode-heating unit, made according to the design parameters specified in the claims, is about 2500 kW, durability is about 10,000 hours, the efficiency (efficiency) is about 50% ( examples 1-3).

In contrast to the mentioned klystron with samples of the cathode-heating unit made outside the limits indicated in the claims, the output power of which is less than 1500 kW, the durability of 5000 hours, the efficiency (efficiency) is about 40 percent (example 5) and the sample prototype, whose output power is about 700 kW, efficiency of about 30 percent. A sample of the cathode-heating unit does not provide structural rigidity (example 4).

Thus, the claimed cathode-heating unit will provide in comparison with the cathode-heating unit of the prototype

- increase the durability of the cathode-heating unit and, accordingly, a powerful klystron,

- a significant increase in the power of the klystron by more than 3 times and the efficiency of about 50 percent (in pulsed mode),

- reduction of weight and size characteristics of the cathode-heating unit and, accordingly, a powerful klystron,

- expansion of functionality, thanks to the ability to work in both pulsed and continuous mode.

Information sources

1. B.C. Medovnikov. The creation of powerful and heavy-duty klystrons based on multipath electron-optical systems // Radio Engineering, 2000, No. 2, p. 58-61 //.

2. B.Ch. Dubois et al. Cathodes for high-power multipath microwave vacuum devices. // Microwave Technology, Vol. 1, 2011, p. 44-53 is a prototype.

Claims (5)

1. The cathode-heating unit for a powerful klystron, containing several individual cathode modules of a given size, each of which consists of a cathode block of elementary cathodes, a heater, a holder, a screen and which are coaxially arranged with klystron span tubes, characterized in that the cathode-heating unit contains individual cathodic modules in multiples of four, part of the holder of each individual cathode module to a height of (0.2-2.0) mm from the end opposite to the working - emitting - surface, made with a diameter, p overshot the diameter of the cathode module by (0.2-10.0) mm, the cathode-heating unit is additionally equipped with two cylinders - external and internal, with given diameters, respectively, height - external, equal to the height of an individual cathode module or not more than two its heights, internal - equal to the height of the cathode module or not less than 0.5 of its height, each with a wall thickness (0.3-0.8) mm, while the cylinders are coaxially located one in the other in the plane of the working - emitting - surface of the cathode modules, each cathode module optionally with It is loaded with a separate cylinder, placed in it with a gap and fixed by means of the aforementioned part of the holder, while a separate cylinder is made with a diameter that ensures the coupling of all cathode modules with a height less than the height of the cathode module by (1.0-5.0) mm, with a wall thickness equal to (0.2-0.6) mm, on the outer surface of the end face of each individual cylinder in the plane of the working - emitting - surface, the mounting elements are made integral, each in the form of a circular segment, with its curve length (4.0-8, 0) from the wall thickness of an individual cylinder multiples of four, and individual cylinders with separate cathode modules are located between the outer and inner cylinders to ensure that the ends of each individual cylinder are combined in the same plane with the individual cathode modules with fasteners and ends of the outer and inner cylinders and are fixed to each other by means of fastenings at contact points that are multiples of four, the specified diameters of the outer and inner cylinders, the diameter of the exceeding part of the holder are determined from the expressions, respectively
Dext.c = Dc.pr.pipe + Ddec. cylinder.km.
Dvts.ts = Dts.pr.pipe-Dotd. cylindrical km.
Dpr.h.d. = Ddend cylinder.km.-2 × S, where
Dts.pr.pipe - the diameter of the location of the centers of the passage pipes of the klystron, mm,
Dotd. cyl.km - the diameter of the individual cylinder of the cathode module, mm,
S is the wall thickness of the individual cylinder of the cathode module, mm, and all of the mentioned elements are made of refractory material. 2. The cathode-heating unit for a powerful klystron according to claim 1, characterized in that the separate cylinder of each individual cathode module is integral with fastening elements on the outer surface of the end face in terms of the plane of its working - emitting surface - for example, the stamping method and the method spark processing, respectively. 3. The cathode-heating unit for a powerful klystron according to claim 1, characterized in that the individual cylinders with separate cathode modules located between the outer and inner cylinders are fixed to each other by fasteners at contact points that are multiples of four, for example, by welding. 4. The cathode-heating unit for a powerful klystron according to claim 1, characterized in that the refractory material can be molybdenum, tantalum. 5. The cathode-heating unit for a powerful klystron according to claim 1, characterized in that the outer and inner cylinders can be made with stiffeners.

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