Патент USA US2406276код для вставки
All@b 20,1946.v 2,406,276 G. M._wHlTE _ELECTRIC DISCHARGE DEVICE 'F'uedùom 13, 1942 ' W ln ,.u:r ì . .\ ä .v w Y Ivm/en' George M ¿u? H is Attorney. l2,4116,,276 Patented Aug. zo, 1946 George M. White, Schenectady, N. Yi, assignor' to General Electric' Company, a corporation of New York . Application November 13, 1942, Serial No. 465,401 ' Y s claims. »f (o1. 25o-27.5) _ ` ,Y 1 My invention relates to electric discharge de vices, and more particularly to the construction. of space resonant electric discharge devices of the of metalfor material thereonfandan appropri- ' ’ magnetron type. reduce the probability of an arc-over between the ately `positioned and designedY insulator having a long leakage path is employed to eliminate’or In the widespread use of electric discharge electrode structure and the associated magnetic devices of the magnetron type, it is important pole pieces.` that there be a desired symmetry of elements, ' For a better understanding of‘my invention, Y. Y . _ Y or‘ electrodes, in order to obtain uniform _ener reference may be had to the followingy descrip ' gization of associated space resonant regions, or cavities, Without sacrificing the power output of tion takenin connection with the accompanying draw-ing, and its scope will be pointed out in the the device »by a construction which lcauses the appended claims. Fig. 1 Ídiagrammaticallyl illus establishment of inordinately high voltage gradi ents across insulating parts of thestructure which trates` an embodiment of my invention as applied would require a reduction in the nominal power type employing a metallic envelope or vcontaining to: an ultra high frequency magnetron >of, the ' ` output, or cause damage to the elements, or elec member and >which includes a pair of permanent- Y trodes, of the discharge device, thereby necessi tating its withdrawal from use. View of the~anode structure, *andFigB is a de- , It new It vide vice ly magnetized ñeld members.V Fig.,2 is a detailed tailed view ofthe suspendingand vcentering in is an object of my invention «to provide a and improved electric discharge device; is another object of my invention to _pro a new and improved electric discharge de' of the magnetron type. sulatorand‘cathode construction._ . _ Y _ Fig. 1 of the accompanyingdrawing _diagram matically illustrates anfembodirnent- of my inven tion as applied to an eleotric‘discharge device o'f _the magnetron type employing a pair of mag I_t is another object of my invention to provide -netic field pieces oppositely disposed relative to a , new and improved structure for supporting the elements of a magnetron of the space resonant centrally located anode structure including a space _resonant cavity, orcavities; andFig.' 2 'is type which permits operation of the device at rel atively high voltages, and which does not disturb the desired symmetry ofthe electrostatic and mag netic fields required> for-satisfactory operation. a detailed view of the anode structure. Referringparticularly to _ _ _ 1, there is shown an- elongated cylindrical containerthelateral wall ' It is >a still further object of my invention to 30 structure of which is'provided `by a single metal provide new and improved cathode supporting structure for ultra high frequency magnetrons wherein shielding means are provided to prevent envelope or containing member` I, preferably Ao_f the deposition of conductive material on associ The ends Voff-the containerare _enclosed by’fl'anged _ated insulating structure, » -~ tubular form, constructedjof a ferro-magnetic material such as cold rolled steel,` or,the_1_ike,_ 35 Briefly stated, in the illustrated embodiment of my invention, I provide a new and improved ultra members 2 and 3 which are welded or otherwise herrmeticallyy joined to the containing member II. The outerîsurface ofthe envelope orf-member l_ high frequency electric discharge device-of the may be'providewith. a plurality of heat dissi magnetron type comprising a space resonant re gion, orregions, energized in accordance with l pating‘m’eans such as fins (not shown), the oscillations, or motion, of the electrons con stituting the space charge between an anode and a cathode, and in which the cathode is main -tained in spaced relation with respect to the anode structure by means of an improved rigid The anodestructure comprises a circular mem ber`which has a relatively large central opening 5 Vand a series of smaller openings r6 Varranged symmetrically about the central opening 5. The cableconstruction, which affords rigid position central opening ris joined tothe openingsjs Aby means of, a plurality ,of radially-_extendingslots 1. ing of the cathode without entailing the estab lishment of excessively high voltage gradients across the insulating parts and which, by virtue of its symmetry, does not materially disturb the magnetic or electrostatic ñelds required for the - , The anode structure 4, which preferably con 50 sists of copper, >issupported by being brazed to the interior Wall surface of member I. To facili tate thebrazingl operation,- small `channels 8 are cut into the outer periphery of the structure 4, most effective operation of the device, or system. In addition, shielding means are positioned rela tive to the cathode and the insulating structure to prevent the establishmentof aconductive layer _ Within the containing member l and approx imately at its central region there is provided an anode structure 4 `shown in plan view in Fig. 2. 55 and. these areoused to receive rings of Ybrazing material applied before the anode _structure is ` energy factor. One of the materials which may y ,K inserted within the containing member I. A rela tively-large circumferentially extending channel-Y VI) serves to reduce .the overall weight of the struc ture.> `* ' .' f beY used for this purpose is that class of 'alloys including aluminum, nickel and'cobalt.> Alloys of this type are described, for example,Y in thev ' Within the central opening '5 of the anode structure, I employ an indirectly heated cathode Mishima Patents No. 2,027,994 to No. 2,028,060. As a means for providing a low reluctance con comprising a sleeve Iû, of nickel or other suitable ' nection between the base endsof the `magnetic pole pieces I6 and I'I, the pole pieces may be re material, havingfñan'gesj I and l2 at the ends,` spectively seated upon relatively 'thick disc-like’ thereof. This sleeve, >which may be coated ex ternally with a suitable »activating material such _ members I8Y and I9 constructed of ferro-mag as barium oxide, contains a ñlamentary heating Y netic material, such as steel. For the purpose of element I3 by which the sleeve Il] may be» main-tained at an electron emissive temperature. One ïsecuringthe pole pieces rigidly to the discs I8 and I9, I may employ clamping rings 2i? and ZI end of the cathode sleeve lil is closed by a/ínetal slippedfover the pole pieces and welded to the disc I4 and the'other end of the sleeve is closed discVV members. „ by an apertured disc I5. ' _ ' The desired precise placement of pole pieces I6 ’ I VThe discs I4 and I5.have diameters Vof sußicient ‘ and Il with V,reference to the anode structure 4 may AIce_obtained by the use of spacing rings 22 ` and 23'.v As will be observed from Fig.,1, each of these rings is interposed between one surface of the anode 'structure ZI and ytheV surface ofthe ap > dimension to substantially shield insulating struc'- _, ture, to be Ydescribed presently, to prevent. the deposition of an appreciable conductive layer on ythe ' surf ace of the , insulators; which , would`V tend to reduce the operating voltage` of the discharge ertured discs'24, 25, each disc in Vturn being in abutment with a properly positioned and formed du'ctive layer would-tend to` establish relatively shoulder on the adjacent pole piece as indicated low resistance leakage paths between elements at 255 at 2S and Z'I. The spacing 'rings 22.»and 23 may substantially great .differences of potential. ' >In be welded in place before vthe pole pieces are in ther operation "of the .electric discharge device a se'rted within the containing member I.» ’ spacecharge is developed inïthe space between Pole pieces I6 and I I, inasmuch asethese ele, the cathode sleeve II) and 'the surrounding anode, Y ` ments are positioned within the containing'mem device, or the ‘systemes a whole, since the _con structure ¿I by the'application'of a lsuitable po 30 'ber I,‘ may be employed eis-supporting means for tentialimpressed between'the cathode structure the cathode structure. This may-'be done, 'for ` andthe containing member I. The containing example, by constructing `the pole pieces I6 and member I, to which the anode structured is di- j I'I to have alined central openings `cr-centering rectly connected, may have-impressed> thereon a channels 28 and 29,Y respectively, preferably` Yof unidirectional potential, such as'apositive poten circular cross-section and which extend along the axial or'longitudinal dimension of the pole tial„ and the other terminal for the unidirectional circuit' is connected to the cathode structure .by apparatus tol be described presently. ' ' and ' pieces afford communicating -' channels through which elements to be described-presently I ' The electrons which constitute the space ch’arg extend or are positioned, and which presentV are given a spiralï'or orbital motion by a magnetic 40 alined openings 36 and 3l in the respective pole field which is providedby electromagnetic struc ture, or by permanently‘magnetized ñeld pieces faces. ' y to be describedv presently. >The resultant gyra Referring to magnetic pole piece I 5f in particu lar, I provide a relatively rigid concentric-con „tionsor oscillations of the‘electrons constituting i ductor construction for supporting the cathode the space charge produce excitation of the anode centrally within the enlarged opening 5 .of the structureV at a Vfrequency which is correlated to anode structure-4, and which also is employed-,as the natura-l> frequency'ofthe >space resonant re gions which is determined by the physical dimen sions of the openings 6 considered in conjunction with the slots '1. The function of the anode a means or conduit for supplying energizing cur rent to cathode heating element I3. Of course, structure in this respect may be explained from one point of View by considering that' it is made up of a plurality of space resonant regions in’each 50 , one conductor of the cathode is also employed in connection with an externalcircuit'by virtue'of which Ya unidirectional potential isvapplied be Considering j tween vthe anode and theY cathode. more specifically the concentric cable-‘construc of which inductance is provided by a wall surface bounding one of the circular openings v6 >>vand tion, I provide-a cable having an inner "conductor 32 and >an vouter conductor, 33, preferablycon capacitance is provided by the opposing surfaces structed of a metal such asY nickel or molybdenum, ~ of Yone of theV slots 1. »Assuming this point of view, it will be seen that the operating frequency is in and which are'maintained'in spaced relation with respect to'each other by vacontinuous insulator, a large measure determined by the dimensions of the openings 6. - ' In order to provide a magnetic field of sufñcient intensity to permit the apparatus to function in ` 60 such as a tubular insulator 34.' ` Conductors@ and 33 are connected ,to externallyaccessible lead-in wires 35 andA 36 which are sealed in yal its intendedrmanner, there are provided Within the‘containing member I tapered magnetic pole suitable insulator, suchV asa vitreous insulator 31. In order «to facilitate the attachment of the insu lator 37 to the body of the dischargedevice, and pieces I6 and I‘I which are directedaxiallyrof the 65 more particularly to the flange member 2, I may Y containing memberl andmay extend in 'close employ a cylindrical metallic member 38 which is proximity to the upper and lower surfaces Yof the welded or soldered to member 2’ and sealed to anode structure 4. For presentl purposes, Ythese conductor 31. v, ' _ ` ‘_ pole pieces maybe assumed to be permanently Í I provide within the channelV 23, an insulator magnetized in such a sense that the north pole 70 39, the details of which are shownïin Fig„3. In-` of one faces the south pole of the other. To assure Ythe existence of the magnetic Vfield o-f the required intensity, the pole pieces I6 and I__1 should be constructed of a magnetizable sub sulator 39 Vserves as a supporting and centering means for the concentric Acable comprising con ductors 32 and V3.", andv closelylñts- _thefchann’el wavllrby virtue of the `part 39a thereof ,which stance >having a high coercive force and a high 75 closely vengages and is fitted to the 'channel wall. 2,406,276 5 6 Insulator 39 is located near the end of channel 28 in the vicinity of the cathode and is provided with a section 39h of restricted diameter and which extends beyond the pole face 40 of mag netic pole piece I6. In order to place and main tain the insulator 39 in the desired axial posi tion, I provide a tubular spacing member> 4I in abutment with the insulator 39 and extending therefrom to the base of magnetic pole piece I6 where it engages or abuts the disc I8. The mem . which may be connected to the concentric trans' mission line comprising conductors 5I and 52. 'I'he various space resonant regions, or cavities, are excited or energized in accordance with the oscillations or motions of the electrons constitut ing the space charge within the region defined by the cathode sleeve I0 and anode structure 4. The period of oscillation .of the electrons con stituting the space charge, or a portion thereof, is correlated with respect4 to the natural-reso ber 4I is closely fitted to the surface of the chan nance frequency ‘of the various space resonant `nel wall and serves as a means for preventing regions comprising openings Ii and slots ‘I to` undesired axial movement of the insulator 39 maintain the regions in oscillation, and energy may be derived from all the regions through the and the associated cathode construction. Y The concentric conductor also serves L as a loop 50 and conductors 5I and 52. ' Discs I4 and I5 shield insulators 45 and 39, re spectively, from the cathode and thereby pre serves as a means for impressing a potential, vent the electrons from striking the insulators, such as a negative potential, on the cathode. which would otherwise be the case due to the Conductor 33 may have a flanged part ’42 at 20 axial movement of those electrons which pass beyond the boundaries defined by the top and its lower end to engage firmly disc I5, and the means for supplying current to the cathode heat ingr element I3, and the outer conductor 33 also inner conductor 32 may be bent over, as shown at 43, to prevent undesired axial movement or stress of the inner conductor relative to the in sulating member 34 which is interposed between part 43 and the fianged part 42 of outer con ductor 33. A spacing ring 44, preferably con structed of nickel, is placed between insulator 39 and the upper surface of disc I 5, Vall of these members being in close contact and engagement 30 so that the heat transfer from the cathode to the insulators 39 and 45 is minimized. It will be noted that therestri'cted part 39D of insulator> 39 aiiords an appreciable annular space between its surface and the wall of chan nel 28, thereby providing a long leakage path between the cathode structure and the pole piece bottom surfaces of anode structure 4. Even though the sides of the insulators collect any conductive coating incident to the relatively high temperature of the cathode”, the increased length of leakage path will prevent breakdown which would otherwise result from creepage along the surface of an improperly positioned and designed insulator. ' Another advantage ofthe construction which I provide is that the insulating paths, particu larly that of insulator 39, with respect to ground' >are many times greater than that afforded by the prior arrangements, and consequentlyfor a given applied voltage it is possible to use mate rials having a somewhat smaller dielectric strength, Furthermore, by virtue of the above described construction, the tendency to produce I6. In this manner, even though the conductive layer tends to be deposited on part 39h of insu short circuits in the cathode assembly,` is ma- . lator 39, there is nevertheless afforded a suñi 40 terially decreased since the two terminals or ciently long leakage path to reduce or minimize’ conductors for the cathode heating element I3 the probability of arc-over between pole piece I6 are well insulate'd from each other and are of strong mechanical construction. and the cathode structure. Some of the other advantages incident to Within the channel 29 of magnetic pole piece my above described construction for »the electric I'I, I provide an insulator 45 which centers the discharge device include ease of mechanical as lower end, and particularly disc I 4,'of cathode sembly made possible by the simplicity of con construction and supports a metallic pin 43 struction, particularly the single upper insulator which is turned over at its upper end and to and the rigid concentric cable. In addition, the ` which the lower terminal 41 of cathode heating element I3 is welded or soldered. The upper 50 generally symmetrical configuration ofthe ele- , terminal 48 of the cathode heating element is welded or soldered to the inner conductor 32. ments, or electrodes, of the discharge device and the associated conductors and insulators reduces the possibility of establishing excessively high or dangerous voltage gradients which would ordi firmly maintaining the cathode construction and 55 narily tend to be present at the ends of chan I also employ between disc I4 and insulator 45 a metallic ring, such as a nickel ring 49, for nels 28 and 29 facing the -anode structure 4. the insulator 45 in the desired íixed spaced rela tion and for minimizing heat transfer. Inasmuch Certain features of the electric discharge de as insulator 45 is iirmly positioned against the vice shown in Fig. l, including the metallic con taining member and the permanently magnetized wall of channel 29, it will be appreciated that axialv as well as radial movement of the cathode 60 magnetic iield members, are disclosed and broad ly claimed in a Ycopending patent application of construction is prevented. As a means for Vextracting energy from the Elmer D. McArthur, Serial No. 447,903, filed June , discharge device, I may employ an output elec 22, 1942, and which is assigned to, the assignee of the present application.` Other features re trode means, such as a loop 50, extending into one of the openings 6 and which may constitute 65 lating to> certain aspects of the rigid cable con an extension of a center conductor 5I of a con struction are disclosed and broadly claimed in centric transmission line comprising conductor 5I and an outerconductor 52 which aresealed Y by means of a glass or vitreous seal 53. copending patent application Serial No. 465,424 of Ralph J. Bondley, filed concurrently herewith and'which is also assigned to the assignee of this Upon the application of a unidirectional volt 70 application. While I have shown and described my inven age between the anode structure and the cath > tion as' applied to a device embodying various ode, the electric discharge device effects vener gization of the various space resonant regions, elements diagrammatically shown, it will be obvi comprising openings 6 >and slots l, to supply ultra ous to those skilled in the art; that changes and high frequency energy to a> utilization circuit 75 modifications may be made without departing 2,406,276 7 . 8. from my invention,'and I', therefore,- aiminthe positioned within 'the channel Vof the other pole appended claims to-fcover all such changesV and modiñcations as fall Within the true spirit and tallic pin positionedv by‘said insulator and con scope of my invention. nected to the other terminal of said cathode heat ' ~ ‘ ' What I claim as new and desire to secure by ' piece near'the region of the pole face, and a me- ~ ing'element and said cathode. . Letters Patent of the United States is: l. An electric discharge device comprising a 5. An electric discharge device of the magne tron type comprising o, plurality of enclosed co pluralityvoi enclosed co-operating electrodes in operating electrodes including a thermionicicath- . ode including a cylindrical sleeve coatedowith an cluding an anode structure having a centrally lo cated opening therein and -a cathode, a pair of 10 electron emissive material and a cathode heat magnetic pole pieces positioned on opposite sides lof said anode structure and each including a channel lying longitudinally of the pole'piece and v being alined With respect to each other vand with respect to said opening', a pair of insulating means each pcsitioned'in one of said channels ing element Within said sleeve, an anode> struc ture of general circular coniiguration provided with a circularY center opening Within which said cathode is positioned and including a space reso' nator to be energized in accordance with the motion of the electrons constituting the space charge between said cathode and said anode. structure', a pair of magnetic pole pieces respec andv each having a portion engaging 'the walls of the channel at a regionspaced from the pole tively positioned on opposite sides of said anode face anda second portion extending from the channel beyond the pole face, Vsaid last men 20 structure for establishing a magnetic ñeld Within the space deñned by said cathode and said anode tioned portion having a smaller cross section than the channel, and means extending through structure and each having therein a channel po sitioned longitudinally of the pole piece, means said insulating means supporting and centering supporting said cathode comprising a concentric` said cathode. 2. An electric discharge device comprising a 25 cable extending through th‘e channel of one of said pole pieces and including an inner conduc plurality of enclosed (zo-operating electrodes in cluding a, thermionic cathode including a heating tor, an' outer concentric tubular conductor and an insulating material therebetween, an insulator element andan anode structure surrounding said cathode, a pair of magnetic pole pieces spaced on positioned in the channel of one of saidpole pieces and inl close engagement' therewith sup opposite sides of said. anode structure and each having therein a channel of circular cross section porting and centering said cathode', means con necting one terminal of said cathode >heating‘ele positioned longitudinally of the pole piece, means supporting said cathode and for supplying cur-` ment to said outertubular conductor, means com- . prising a pin connecting the other terminal of >rent to said heating element comprising a con centric -cable construction including an inner and 35 said cathode heating element to said cathode structure and constituting a part- of an energiz outer conductor extending through the channel of one of said pole pieces, an insulator fitted in ing circuit for said cath'ode heating element, a' second insulator positioned Within the channel of the channeloi- said one pole piece centering and the other pole piece and centering said pin, and 1 ` supporting said cable, and aY tubular spacing member extending from the vicinity of said in 40 a pair of shielding members closing the ends of the cathode sleeve and of dimensions suiîicient sulator toward the base of said one pole piece. 3. An electric discharge device comprising a to shield said insulators Yto prevent the deposition plurality of co-operating electrodes including 'a of conductive material thereon incident to the vaporization of electrons from the emissive sur cylindrical cathode and an anode structure of ` annular form having ltherein a central opening 45 faceof said cathode. 6. An electric discharge device comprising a within which said cathode is positioned, a pair of magnetic pole pieces spaced on opposite sides ’ plurality of enclosed co-operating electrodesV in cluding a cathode and an anode structure sur of said anode structure, said pole pieces each h'av rounding said cathode, a pairof magnetic pole ing therein a channel positioned; longitudinally of the pole piece, a rigid cable construction lying 50 pieces spaced on opposite sides of said anode within the channel of one of said pole’ pieces sup structure', said pole pieces each having therein a channel positioned longitudinally of the pole porting said cathode, an insulator in said channel piece, means positioning said cathode compris near the end -thereof facing said anode structure supporting and centering said cable, a second in ing a'fconce'ntric cable construction attached to sulator in the channel of the other pole piece and 55 said cathode and‘extending through the channel of one of said pole pieces, an insulator support including- a member centering said cathode, and ing and centering said cable and' close-ly'v engaging a pair of shielding members at the ends» of the cylindrical-cathode to prevent the deposition of the channel Wall of said pole piece, and a copper conductiveY material on said insulators. sleevein abutment with said insulator andl close 4. An electric discharge device comprising a 60 ly ñtted tothe channelwall and extending from plurality of co-operating electrodes including a said insulator to .the baseof- said one polev piece. ^ 7. An electric discharge device comprising a cathode having a cylindrical sleeve provided with plurality of co-operating'electrodes including a an electron-v emissive surface and Y an annular anode, structure havingy therein a centrallopening cathodel and „an anode structure surrounding said within which said sleeve is positioned'. a pair of 65 cathode, a pair of magnetic pole pieces'> spaced magnetic pole’pieces spaced on opposite sides of onopposite sides of said yanode structure'and each said anode structure, said polepieces each-having therein a channel vextending longitudinally- ofthe pole piece, a rigid cable construction ¿lying within having therein a channel of vcircular cross sec tion positioned longitudinally of the pole piece', anda concentric tubulan outer member, afrcath ode- heating> element'substantially» surrounded byv means positioning said cathode comprising a` concentric cable- construction attached to said cathode for supplying current-to» a cathode heat ì ing element and extending throughV the channel of one of- said pole pieces; an insulator centering said sleeve- and having `one lterminal conductively` and supporting said cable located Withinv the ' the channel of one or" said pole pieces supporting said» cathode and’comprising an inner member @soneries tof Said-„inner Conductor, „aniinsnlator 7:5 challlieiwithin.; the; vicinity cisaidA cathode ,- and 2,406,276 10 in close engagement with the channel wall, and a, metallic tube in abutment with said insulator and extending therefrom to the base of said one pole piece. ~ 8. An ultra high frequency electric discharge device comprising a plurality of enclosed co operating electrodes designed to have electrical in alinement with each other, means supporting’ said cathode comprising a rigid concentric cable construction including spaced inner and outer conductors and extending through the channel of one of said pole pieces, an insulator in close engagement with the channel wall of said one pole piece and extending beyond the pole face and geometrical symmetry about a longitudinal thereof in the direction of said cathode,V a cen axis and 4comprising a cylindrical thermionic tering insulator in the channel of the other pole cathode and an annular anode structure provided 10 piece and supporting a metallic pin in electrical with a circular central opening within which contact with said cathode, and a pair of shield said cathode is positioned, a pair of magnetic ing discs positioned between said cathode and pole pieces spaced on opposite sides of said anode said pole faces to prevent the deposition of con _structure and having pole faces of substantially ductive material on said insulators incident to circular cross section, said pole pieces each hav 15 the vaporization of electrons from the emissive ing therein a channel of circular cross section surface of said cathode. positioned longitudinally of the pole pieces and GEORGE M. WHITE.