US2666160A - Disk seal tube - Google Patents

Description

R. M. BOWIE DISK SEAL TUBE Jan. l2, 1954 Filed June 24, 194e INVENTOR.

ROBERT M 50W/ /L//S /TTORNEY Patented Jan. 12, 1954 DISK SEAL TUBE Robert M. Bowie, Manhasset, N. Y., assignor to Sylvania Electric Products, Inc., a corporation of Massachusetts Application June 24, 1946, Serial No. 678,825

14 Claims. (Cl. 315-5) The invention relates to a tube mounting, par-f "fltics will be pointed out where pertinent to a full ticularly to the mounting of tubes of the discseal types.

Certain types of electron devices, generally related to the tron family, such as the magnetron and klystron, employ electron tubes which are designed to operate in close proximity to cavity resonators and, to facilitate electrical connections thereto, may be constructed with disc-seal electrodes. rIhe mounting of a disc-seal tube within such an electron device has been a delicate as well as a complicated operation, particularly from the standpoint of easy accessibility for repair or replacement purposes.

A principal object of the invention is to provide improved means and method of mounting a discseal type tube within the cavity resonator of a cavity type electron device, such as an oscillator, an amplier, or the like.

Another object is the provision of an arrangement for improving the radio frequency contact between the cavity resonator and means which support the tube within the cavity.

A special object of the invention is the provision of simplified means for clampingthe smaller disc shaped connector of a disc-seal tube into the cavity of a resonator.

` Other objects of the invention have to do with novel features of construction which will become apparent as the description proceeds.

Fig. 1 is a sectional view of an electron device` having a radial cavity resonator in which a discseal tube is mounted in accordance with the present invention; f

Fig. 2 is a longitudinal sectional, view of a different type of electron device having a disc-seal tube mounted in a concentric line cavity resonator;

Fig. 3 is an enlarged fragmentary sectional view taken on the line 3-3 of Fig. 2, showing a sheet metal disc spun over the edges of a shoulder of a collar member; and

Fig. 4 is a similar View showing a preferred form of the construction illustrated in Fig. 3.

In the drawing only suicient structure is shown of the electron device as is required to illustrate the invention. I have elected to disclose the invention as applied to a magnetron `and a klystron in conjunction with a radial cavity resonator and a concentric line resonator, respectively. For the sake of convenience, in describing the two forms of cavity resonators illustrated herein, similar reference characters indicate corresponding parts as far as practical. However, diierences in structural characterisappreciation of the invention.

Referring particularly to Fig. l, the reference character I designates generally a radial cavity resonator which may be employed with a magnetron. As is Well known a magnetron may be a high-vacuum cavity oscillator, and at least one conventional form of a magnetron has a disc-seal tube mounted in the cavity resonator. In the past a split cavity has generally been used in mounting the disc-seal tube within the cavity because such tubes were often made with both discs of the same diameter. Although the provision of one smaller disc would have facilitated insertion into an unsplit (non-segmental) cavity, difculty would have been encountered in firmly clamping the smaller disc in place. The present invention contemplates primarily means for firmly clamping the smaller disc electrode into the cavity resonator. Under most circumstances this operation is very trying, and any construction which simplifies the operation may be regarded as an advance in the art.

Referring to Fig. 2, there is disclosed an electron device of the concentric line cavity type such as represented by a klystron. This device is also a high vacuum oscillator employing a cavity resonator, but of the type known as a concentric line cavity. The cavity resonators of these two type oscillators, i. e. magnetron and klystron, as herein shown, are of different construction but generally they function similarly. In. those respects in which the resonators function differently, they have no bearing on the present invention.

With this general understanding of the application of the present invention, reference may again be had to Fig. l. The disc-seal tube 2 has a plurality of electrodes (not shown) some of which are provided with radially disposed discshaped terminals. According to past practice these terminals were of the same diameter and severally clamped into the inner margin of the cavity resonator. In the present construction one of these terminals comprises a metal disc 3, which is suitably sealed through the envelope of the tube 2, and connected to an electrode thereof. On one end of the tube 2 there is provided an external collar structure 4 having a cylindrical body portion provided with threads 6. A second sheet metal disc I, which may be copper, is also sealed through the envelope and joined to the collar 4. The manner in which the disc 'I may be spun over the edges of a flange on the collar 4 to improve the radio frequency contact between the disc and the adjacent conductor of the cavity resonator I will be more fully explained hereinafter in connection with Figs. 3 and 4. It will be noted that the terminals comprising the discs 3 and 'I are concentrically disposed and longitudinally displaced along the axis of the tube I, and are of different diameters, disc 'I being of smaller diameter than-disc 3. It will also be noted that the spacing of discs 3 and 'I, With respect to each other, must conform to the depth of the cavity resonator. The reason for this latter feature will become obvious as the description proceeds.

It will be noted from the drawing that the cavity resonator I is of a one-piececonstruction. Referring particularly to Fig. 1,.'th'eresonato1nis primarily a fiat hollow cylinder having end walls 8 and 9 provided with concentrically arranged circular apertures II and I2, respectively. The aperture II is of larger diameter than the aperture I2, the aperture I I being formed on the outer orflefthand end wall of the resonator, and the aperture i2 being formed on the innerorright hand end wall thereof. ,Surrounding the apertures II and I2 are shoulders Iand M respectively, formedcontiguous to the margin vofthe said apertures. rIlhese shoulders constitutemeans for concentrically lOQatlg the vdisc-seal .tube 2 within the cavity resonator I, the arrangement being that theyact asia bearing surface for the edges of discs 3 and ,'I. That is to say, the diameters of the apertures II and I2 correspond substantially to the diameters vof discs 3 and `'1, Yrespectively, so that Ythe peripheral edges ofsaid discsare adapted to register with theshoulders I3 and I4,.respectively.

The'disc 'I, being of smaller diameter than the aperture ISI passes easily therethrOllgh, and is adapted to vregister withthe shoulder I4. The

isc Iv is retained on the shoulder .M byrneans of an'internally threaded nut I5, the threads of which .engage the external threadsl on the collar 4. Bytightening the nut I5 rthedisc 'inlay be drawn into intimate Contact withthe .shoulder I4. As mentioned above, the copper disc 'I may be spun` over the edges of a flange on collar i and isthus placed in direct contact With theend wall of the Cavity resonatorl So thattho ,shoulder .M abuts against the spun disc I rather than ,dire'ctly against the collarA.. By virtue ofthis construction the radio frequency contaetbetweenthe disc and the cavity resonator isfrnerepositive, and for obvious .reasons constitutes van improved connectionfortheresonator. n

.The disc 3in accordance with the. eonstruction illustrated in Fig. l, is retained upon the shoulder I ,Bbythe ring I6 having a depending flange I1 formed upon the peripheral edge of the ring I6. The flange IJ ntssnugly into the apertures I.I and issecured in place by screws I0 which pass throughholes `in the ring .i6 and engages suitable threads formed in the outer surface of end wall 8 of the resonator I. The mounting of the discseal tube `2 within the resonant cavity may be accomplished by inserting the smaller end of the tube through the apertures II and I2. The nut I5, when tightened, holds the collar 4 in position, and ring IB when properly positioned with respect to the threaded holes on the adjacent wall of the resonator, secures the diScSyinipIace. It is obvious that in accordance with this construction, to remove .the tube 2 .from the cavity resonator, all that is required is to loosen the screws I0 and the nut I5. This frees the tube 2 of its clamping means andpermits the ready Withdrawal thereof.

Referring to Fig. 2, it will be noted that the general construction of a cavity resonator of the concentric line type is basically diiferent, although having fundamentally the same operating principles as a radial cavity resonator. A concentric line cavity resonator I, according to standard construction, embodies an inner conductor I8, an.outer conductor 2i}-,1and a shortingV plunger I9 which is longitudinally-slidable between the inner and outer conductors to permit adjustment of the length of the resonator Yandhence of its resonant frequency.

is illustrated as .mounted partially .within the resonator I is a Aklystron having an elongated tubular envelope The electron tube which shewnpassing out through-the center conductor i8.. At thefother end the tube isprovided Witha base Ehaving pins 2,1 connected. to other leads sealed through section. Z-I ,of the envelope.V

When the tube is mounted ,in the resonator, sections 22 vand ,23 of the envelope, lwith disc 'I sealed between them,-pass throughfthe openend of the Youter .conductor 2B, `the aperture .being large, enough` to admit disc is' -but having` a. ShOul-- der I3 against which thelargerdisc abuts-when the tube isfully inserted. This-insertion viseompleted Vby screwing threads 6 .of Vcollar vII into threads .2.8 .providedronthe inside of-inner-,conductor I8. The disc 'I may be drawn `-.snuglyguygl againstshoulder lAon-theinner conductor 1,8,

l while the disc .3 will simultaneously abut against l shoulder .I3 `on 'the outer conductor. .Good VcondiseS Vforms no part Yoi the invention, it being' immaterial'whether the device is a threaded ,nut

as kin Fig. 2,a clamping ring I6, as in. Fig. l,

o r any othersatisfaotory arrangement.

The manner 'n vwhich .threaded collar ,4 is

joined to disc 'I so that the inner conductorabuts"l over the'edgesof which the disc Ifisfspun '.'Ihe' inner conductor I8 thus-extends along ,thefsuriace' ofthe disc', .while shoulder I4 on Athe inner surface o f the inner conductor-.abuts against -'the disc. If kthe disc is notspun 4overthe flange T 5 on the V,threaded collar, `but `4merely ,extended along oneV side `of thek hangs, Y.the inner conductor L8 will touch fthe danse. ;5 instead .of the disc directly, and .currents passing :between` the` disc and the innerconductor of the cavity will be required to pass from the disc to the collar and thence to the inner conductor of the resonator, traversing two contact surfaces instead of one.

Since the sectional View of Fig. 3 shows a portion of the interior of the tube, grid electrode 3! appears attached to the inner edge of disc 1.

A preferred modification of this construction is shown in Fig. 4. The flange 5 on threaded collar 4 `is extended so that the disc spun over the flange forms an outer surface which has substantially the same diameter as the inner conductor I8 of the cavity resonator. The spinning of the disc over the edges of the flange is continued so that the entire end surface of the inner conductor may abut against the disc. A relatively smooth and continuous surface is thus formed for the wall of the cavity resonator. In this case the shoulder I4 is unnecessary and may be omitted.

In the arrangement of Figs. 1 and 2 a coupling loop 32 is provided for transferring radio frequency power from the cavity resonator to a coaxial line 33.

Although I have shown and described particular embodiments of my invention I do not vdesire to be limited to the embodiments set forth. It is my intention to cover all such modincations as come within the scope of the appended claims.

What I claim is:

1. A mount construction for supporting a discseal tube within the resonant cavity of an eleotron device comprising a cavity resonator having opposing apertures of different diameters formed in the end walls of the resonator, a discseal tube having a number of electrodes provided with terminals concentrically disposed along a common axis, said terminals being discshaped and substantially corresponding in size and spacing to the arrangement of said apertures, a collar structure secured to said tube for clamping the smaller of said terminals over the smaller of said apertures, and a ring construction for clamping the larger of said terminals over the larger of said apertures, said collar and ring construction being designed to make the tube easily demountable from the cavity resonator.

2. A mount yconstruction for supporting a discseal tube within the resonant cavity of an electron device comprising a cavity resonator having opposing apertures of different diameters formed in the end walls of the resonator, terminals adapted to fit said apertures, one of said terminals comprising a threaded collar attached to one end of the tube and having a flange portion, another of said terminals comprising a disc spaced from said collar and corresponding in diameter to the larger of said apertures, means Within the cavity resonator for supporting said collar and said disc, and means for retaining said collar and said disc on said supporting means, said retaining means for the disc comprising a clamping ring member, said clamping ring member being mounted exteriorly ou the cavity resonator, said retaining means for the collar comprising a nut for engaging the threads on the collar and drawing the ange portion thereof against a shoulder surrounding the smaller of said apertures.

3. A mount construction for supporting a discseal Within the cavity resonator of an electron device, comprising a cavity resonator having opposing apertures of diierent diameters formed in the end walls of the resonator, a shoulder shoulders, a collar secured to said tube for clamping the smaller of said terminals onto the shoulder of said smaller aperture, a ring member for clamping the larger of said terminals onto the shoulder of the larger of said apertures, and means for retaining said ring member in engagement with said shoulders.

4. The mount construction set forth in claim 3, wherein the means for retaining the collar in place comprises a nut adapted to engage the threads on the collar and fasten the latter onto the supporting shoulder surrounding the smaller aperture, and the means for retaining the ring member in engagement with the shoul-der surrounding the larger aperture comprising a threaded connection between the ring member and the outer end wall of the cavity resonator.

5. A mount construction for supporting a discseal tube within the resonant cavity of an electron device comprising a cavity resonator having opposing apertures of different diameter, the larger aperture constituting an entrance to the resonator and the smaller aperture constituting an exit therefrom, a disc-seal tube'designed to be inserted in the cavity resonator, said tube having disc terminals adapted to register with said apertures, and means for retaining said terminals in engagement with said apertures, said retaining means comprising an inner clamping member secured to said tube, said inner clamping member including a threaded collar adapted to form a butt seal with a conductive portion of said device.-

6. A mount construction for supporting a discseal tube within the resonant cavity of an electron device comprising a cavity resonator having opposing apertures of different diameters,

the larger aperture constituting an entrance to the resonator and the smaller aperture constituting an exit therefrom, a disc-seal tube designed to be inserted in the cavity resonator, said tube having disc terminals adapted to register with said apertures, and means for retaining said terminals in engagement with said apertures, said retaining means comprising an outer clamping member and an inner clamping member secured to said tube, said inner clamping member including a threaded collar adapted to form a butt seal with a conductive portion of said device.

'7. An electron tube including an envelope, a disc terminal sealed through said envelope, and a threaded collar carried by said envelope and connected to said disc terminal for urging said terminal into direct contact with a wall of a cavity resonator.

8. An electron tube including an envelope, a disc terminal sealed through said envelope, and means including a threaded collar for connecting said disc to a cavity resonator, said disc being spun over said collar so that said disc may be placed in direct contact with a cavity resonator.

9. The mount -construction set forth in claim 6, wherein the collar structure comprises a threaded cylindrical body member having a peripheral flange portion, and a sheet metal disc terminal: Spunwer'the edeesroftsad flange n0r' tion,;-wherebythe center electrode of the resonator ,abuts against :the Spun dise rather than against the collar per se.

:71.0,- The ymount construction set forth ,in claim 2 whereinthe cavity resonator has an entrance omarger diameter .than the exitthererom, said elli? 31H58 and Vest; providing the supporting me ns ,for the discand collar, said arrangement making the tube'v demountable Without. zdisas- Sembling the resonator.

1;1. electron vtube including an envelope,

an ,externally vthreaded collar [surrounding said errrelope, vsaid Icollar having a flange, andi an annular terminal Sealed through said envelope andpbnded `over said flange- 12,V In Acombination -with lthe electron tube of claimfhha high frequency .cavity havinga shoulderged aperture, an *interiorly threadedpart assoeiated with `said aperture, said threaded co1.- -lar-and threaded part being drawn totighten the Abeaded-over terminal iirrnly between said4 envelope, an externally .threaded collar surrounding. Said envelope, Said collar .having a flange, annular terminal sealed through said envelope and ebeaded over said flange, anaddie tional annular terminal of larger diameter,A than said beaded-,over terminal sealed through,said envelope, said additional terminal .being on the side of said envelope opposite the threaded por-i tion of said collar, acavity having two axially aligned shouldered apertures `of different diameters, spaced apart a distance substantiallyequal to the distance between vthe terminals ofisaid tube, an interiorly threaded part vassociated with the aperturev of smaller diameter and tightened on said threaded. collar to grip the kbeaded-over terminal rnily between said' ange andV the shoulder of said aperture, and another collar .to press said additional terminal against the shoullder oli the other aperture.

ROBERT 4M. BOWLE.

References Cited in the le of :this patent UNITED STATES PATENTS Number Name Date 2,353,743 r/rearthur` July,l isf, 194g 2,367,331 Bondley Jan. 16, 1945- 2,408,355 Turner sept. 24, 1945i 2,408,927 Gurewitsh Oct. 8, 1946 2,412,055 Meahl Deo. 3, 1946 2,412,150 Longfellow Dec. 3, 194:5` 2,413,171 Cliiord et al. Dec. 2 4, 19516.. 2,419,578 Litton Apr. 29, 19,47 2,466,136 Tulier Apr. 5., 19,49 2,473,827 `Spencer, .June 21, 19519

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