US2283894A - Ultra-high frequency tube - Google Patents

Description

May 19, 1942.

' I. E. MOUROMTSEFF EIAL ULTRA-HIGH FREQUENCY TUBE Original Filed Nov. 30, 1938 INVENTOR 1. E. MOV/POMFSZV-F' r MD/IV/V/C/C'. BY

" A ORNEY Patented May 19, 1942 ULTRA-HIGH FREQUENCY Ilia Emmanuel Mouromtsefi, Montclair, and George M. Dinnick, Bloomfield, N. J., assignors to Westinghouse Electric & Manufacturing Company, East Pittsbu Pennsylvania rgh, Pa., a corporation of Original application November 30, 1938, Serial No. 243,116. Divided and this application February 23, 1940, Serial No. 320,394

8 Claims.

This application is a division of our co-pending application Serial Number 243,116, filed November 30, 1938, for Ultra-high frequency tube.

The invention relates to electron discharge devices and particularly such devices that are suit- I able for ultra-high frequency.

An object of the invention is to provide a discharge tube for ultra-high frequency having an output of 100 watts and even up to 250 or 300 7 Watts output.

Another object of the invention is to provide a discharge device having a minimum of inductance between the leads to the electrodes.

Other objects and advantages of the invention will be apparent from the following description and drawing, in which:

Fig. 1 is a view, partly in cross-section and partly in elevation, of a tube embodying the invention.

Fig. 2 is an enlarged View on lines 11-11 of Fig. 1.

Fig. 3 is an enlarged view on lines 1lIIII of Fig. 1.

Tubes utilized in high frequency work have heretofore been limited to a very small power output;

The difficulty has been to efficiently dissipate the heat generated in the grid. Prior schemes for cooling the grid of large size tubes are obviously inapplicable to the ultra-high frequency tube where the electrodes must be closely spaced -together for high frequency use. One of the speciiic objects of our invention is to provide means for effectively dissipating heat from the grid structure to the casing of the discharge device.

without interfering in any way with the spacing between the grid and the other electrodes.

Another difficulty in thedesign of these tubes has been the inductance between the leads to the electrodes. The design of our leads provides a minimum of inductance between the leads of the device.

In the drawing, we have illustrated a preferred embodiment such as illustrated in Fig. l. The figure is drawn to approximately a 50% greater size than the actual tube constructed according to our invention. An exterior anode I!) is utilized in a hollow tubular form having a flare II making a feather edge seal 12 with the glass insulating portion l3 of the casing. The diameter of the active portion of the anode is very small for tubes of this wattage capacity and may be of an interior diameter of a half to three-quarters of an inch as an example. It will be noted that the insulating part of the casing I3 is enlarged to several times this diameter to provide a wide spacing for the other electrode leads therethrough.

' At the opposite end of the tube is a metal portion l4 having a feather seal I5 with the insulating portion. This metal portion I4 is preferably of a cup or knobbed shape having a flare l5 terminating in the feather seal. Fitting into this cup or knobbed shape I4 is a knob of copper l'l having a very tight engagement with the copper portion M. The knob l1 and the enclosing casing M are of sufficient length to provide adequate air cooling and dissipation of heat therefrom. Any suitable shape fins may, of course, be made integral with or to fit upon the knob of the easing it. Integrally attached to the knob H is a shaft !8 extending towards the upper part of the tube. This shaft of copper is of such a size and thickness that there is substantially temperature equilibrium between the tip of the knob I! and the inner terminal [9 of the shaft I8. In case the inner tip I9 is at 100, or 200 degrees, the knob I! will not be more than 10 degrees difference therefrom. Around the inner end IQ of this copper shaft is a ring or collar 20 securing the ends 2| of the grid wires thereto. This support for the grid wires may take any well-known mechanical form such as the ring 23 sweated on to the end of the copper portion with holes providing the very tight frictional fit drilled into the ring 20. The top of the copper shaft may have a hole 22 drilled therein to help the compression of the ring 20 thereon. The top of the copper shaft may also be split about the hole 20 and have the ends of the grid wires 2| in contact thereto and the ring 20 be in the form of a clamp compressing the ends 2| to the top of the copper shaft. As illustrated in the drawing, the grid wires are spaced about the top of the copper shaft to provide for an assembling of the cathode connection to be hereafter described and then these grid wires are bent inwardly at 23 and then extend parallel and longitudinal at 24 with the desired spacing from the anode ID which encloses them. The grid wires; as illustrated, comprise eight, although a greater or less number can be used. An inverted cap 25 is preferably welded to the top of these grid wires to maintain them in place.

Inside of the grid are the filament wires 26 preferably of thoriated tungsten extending parallel and concentric with the grid wires and the anode. This filament construction is more clearly disclosed in the enlarged detailed view in Fig. 4. The top of the grid wires are bent over at 21 and have another smallerwire 28 binding their ends 29 together. The wire 28 and the ends 29 may be welded or soldered together. The number of filament wires illustrated is six although, of course, this number may be varied. It is desirable, however, to have the number an even one. An insulator 30 preferably of a ceramic material supports two discs 3| and 32. The top disc 3| rests on the insulator and is fastened thereto by a bolt 33 extending through the insulator 30. Every other filament 26 terminates adjacent the periphery of this disc 3| preferably by having a wire 34 wound around the end of the filament and weldedorsoldered to the disc where the filament 28 passes therethrough. The disc 32 is placed on a lower reduced portion of the insulator 30 which arrangement maintains it in spaced relationship from the disc 3| on top of the insulator. The upper disc 3| has a cut out portion 35 located at the portions of the periphery intermediate the places of connection of the ends of the filament 26 that are connected thereto. This cut out portion 35 is sufiiciently large so that the alternating filaments may extend down to the disc 32 to be secured thereto in a manner corresponding to the attachment of the other filaments to the disc 3|. The upper disc 3| accordingly has the shape of a circle with parts regularly removed about its periphery. Other shapes, however, may be used to provide a clearance for the alternating filaments to reach the lower disc 32. The bolt 33 preferably passes through another insulator 36 and a fiat arm 3! makes contact with the bolt 33 at the lower surface of the insulator 36. Another arm 38 encloses a reduced diameter of the insulator 35 and a hollow sleeve 39 connects this fiat arm 38 and the disc 32.

The bolt head 33 acting on the upper disc 3| and the lower contact arm 31 bind the structure together. The fiat arms 37 and 38 pass through the space between two of the grid wires and at a suitable distance therefrom are connected at right angles to two solid rod standards 40 and 4| that are sealed through the insulated casing by the broad and extended seal 42 as illustrated. The conducting rods 40 and 4! are in turn connected to flexible conductors 43 by means of a sleeve 44 and in a manner more particularly described in Patent #1,834,132 of W. L. Miller, issued December 1, 1931, for Leading-in conductor.

A shield 45 is preferably placed about the grid wires on a line with the feather edge seal I2 between the anode and the insulating portion of the casing in order that this seal may not be under an electrostatic stress. This shield will also help in maintaining the shape and alignment of the lower portion of the grid wires.

In Figs. and 6 is disclosed a modification of the filament structure of Fig. 4. A thoriated filament 41 is secured to the upper disc 3| and extends upward where it touches the upper portion of two other wires 46 and 48 and is bound thereto by a wire 49 around the very top portion of these three wires. The other end of each of these wires, 46, 41 and 48, then bends downward through the cut out portions 35 of the disc 3| to make contact with the disc 32.

The cathode heating current enters the tube, for example, through the standard 40, passes at right angles to the flat arm 31 to the bolt 33 and from this bolt, by means of the disc 3|, to the one, two, three or more wires connected thereto, through the thoriated filament wires and back to the other disc 32 through the hollow cylinder sleeve 39 to the flat arm connection 38 and then to the standard 4| leading outside the tube.

In operation, the grid will provide an output way beyond the output of the tubes used for the high frequency. This, as previously mentioned, is due to the efficient cooling of the grid. The high temperature of the grid wires will be applied to the upper edge IQ of the copper shaft l8 and due to the thickness of the copper shaft, the knob I! will be approximately of the same temperature. In other words, the shaft I8 acts as a temperature equalizer between the end of the grid and the middle portion l4 of the casing acting as a grid lead-in. The shaft |8 provides a broad and capable path for the transference of heat from the grid to the exterior of the casing. By reason of this construction, an output of 100, 150, 250 or 300 watts can be realized. Because of the fact that the grid cooling means does not interrupt the spacing of the grid with'the filament and anode, a frequency of 60 to 260 or 300 megacycles can be utilized with the construction disclosed.

Many modifications can be made in the form, number and arrangement of the various elements and their combinations in the preferred embodiments illustrated. As an example, the grid structure of Fig. 1 could take the form of the wires bound at the top in Fig. 4.

We claim:

1. An electrode structure comprising two insulators, a bolt and hollow cylinder spacing said insulators, a disc on one side of said insulators connected to said bolt, a disc on said same insulator connected to said hollow cylinder, a plurality of wires forming a cage and having some ends connected to one of said discs and some ends connected to the other disc.

-2. An electrode structure comprising two insulators, a bolt and hollow cylinder spacing said insulators, a disc on one side of said insulators connected to said bolt, a disc on said same insulator connected to said hollow cylinder, a plurality of wires forming a cage and having some ends connected to one of said discs and some ends connected to the other disc, and an exterior connection to said bolt and another exterior connection to said hollow cylinder.

3. An electrode structure comprising a plurality of wires forming a cage with an open end, a sole support for said cage being located only at the open end of said cage and comprising an insulator having two spaced metal contact pieces thereon, the ends of the wires extending to said support being connected at certain ends to one metal piece, and at certain other ends to the other metal piece, whereby a current may flow from one metal piece through said cage of wires to the other metal piece.

4. An electrode structure comprising a plurality of wires forming a cage, a support for said wires being only at one end of said cage and comprising an insulator and two spaced metal pieces on said insulator, some of the ends of said wires extending to said support being secured to one metal piece, and the other ends extending to said support being secured to the other metal piece.

5. An electrode structure comprising a plurality of wires forming a cage, a support for said wires being only at one end of said cage and comrising an insulator and two spaced metal pieces on said insulator, some of the ends of said wires extending to said support being secured to one metal piece, and the other ends extending to said support being secured to the other metal piece, said wires being bound together at the top of said cage.

6. An electrode comprising a plurality of wires forming a cage with an open end, a support for said cage located in said open end only and comprising an insulator and two spaced metal pieces thereon, some of the wires at said end being secured to one of said metal pieces, and the other wires secured to the other metal piece.

'7. An electrode comprising a plurality-of wires forming a cage with an open end, a metal piece in said open end connected to half the ends of said wires, an insulator backing said metal piece, a second metalpiece supported on said insulator, the other half of the ends of said wires extending past said first metal piece and connected to said second metal piece, said wires being bound together at the top of said cage.

8. An electrode structure comprising a plurality of wires the major portions whereof extend longitudinally parallel to a common axis and define a generally cylindrical configuration, said wires at one end of said cylindrical configuration being bent together into an end bundle at a common center, a wire binding said end bundle together, and means at the other end of said cylindrical configuration receiving and supporting each of said wires and constituting the sole support for said electrode structure, said wires being electrically and physically separated their entire lengths between the supported ends and the bent together bundle.

ILIA EMMANUEL MOUROMTSEFF. GEORGE M. DINNICK.

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