US1968051A - Shockproof x-ray apparatus - Google Patents

Description

July 31, 1934. M, MORRlSON l 1,968,051

SHOCKPROOF X-RAY APPARTUS Filed Feb. l, 1955 a WM ATTORN e, Y":gesegnet v;v snooKrRooF X-RAY APPARATUS Westinghouse X-Ray Company, Inc.,`a corpora# f 1 tion of Delaware ApplicationFebruary 1, 17933,: Serial No.` 654,654

' 11 claims. (o1. 250+34)` t"My v'inver'itiopn relates to electron discharge lap' 'aparatos and lparticularly to X-ray apparatus Vwhereingthe,Llmogerjof lan"oper`ator or patient accidentally contacting any high-voltage parts isentirely eliminated;A

L55 In such apparatus of the prior art it is customary toA encase the Qi-ray tube and the highV tension source offenergy therefor in a container and immerse the same in a body of insulating and coolingV material, such as oil. This latter '510 material, Whichjhas'a'higher dielectric strength tha'njair',V enables the spacing between all high tensio-ncarrying parts tobe' considerably less Athanvlould be required for the same'applied voltage infair-,and consequently the X-ray tube v,T may be materially shortened. As the l X-ray tube'necessarily generatesappreciable heat durfingv itsv operationthis maybe `dissipated' some- 'what vvl`'by *the envelope rto -the y surrounding vin- ;sulatinggand cooling .medium and in addition it V20 may be more readily dissipated vby'providing the-anode stem 'of the tube witha 'cooling radi- `ator :likewise immersed in-this body. f

This'results in -a rugged land cornpact Aunit of .a portablena-ture free from the danger of 'elec'- 25 trical shocksand capable vof supplying the vK -ray lthe tube.- This mediumaccordingly` acts as a lter `and affects vto a great extent the .quality of theX rays to which a patient ora sensitized film is subjected.

" j In accordance with my present invention I retain all kthe essential -features' requisite in shcckproof X-ray apparatusY by immersing the high tensionsource andall high tension terminals in oil and utilize afforeshortened' tube as 40 in priorart 'devices to eliminate the'danger of shocks to operator or patient.v In addition I obviate the objectionable feature of allowingV the oil surrounding the high tension* partsuztdat as allter forfthe X-rzvn'rs' emanating from* the V tub'eiby disposing that portion of the envelope through vwhich the lX-raysiemanate from the anode target exteriorly of the casing or tank ncasing the high tension parts 'of the apparatus. For a better",understanding of rthe novel features ofmy present invention `reference may be had to-V the faccom'pa'nying drawing owherein, v -l'lli'gu're 1 isa .sectional view'of a shockproof unit constructed in accordancegwith'myinvene 1 55 non' with; aggregating apparet@ SHOW? in diagrammatical form` for the purposes of sini@I plicity.- Y, n

Figure 2 is an elevational View on lan enlarged scale of the Ytube supporting structure shown in Fig. 1 with a part broken away to` better illustrate the several parts. Y

Figure 3 is an elevational View on a slightly enlarged scale of a modification of the tube s upporting structure of.Figure 1, and ,c Figure y4 isan elevational View on a slightly enlarged scale of still another modication of the tube supporting structure with a partbroken away for ,the purposes of better illustration.

Referring now to the drawingin detail I have shown in 'Figure 1 a casing 5 which may vbe of a light durable meta1 and suitamy con- 10 nected to ground as at 6. A high tension trans*- immersed in a cooling and insulating medium, r7.5

lsuch as oil 9. The primary winding 7,.receives electrical energyy from a suitable source of. alternating current of the usual commercial p oten'tial"through a pair of conductors 10 andA l2 .which passrhrougha suitable insulating mock 80 or termnallS providedin the Wall of the cas- FAn' Xg-rayvrtube having Yavitreous:evacuated Y .envelope .14, afthermionic cathode 15, Aand-*an anode 16 is secured to the casing-5, infa manner R85 lto be" hereinafter-l more-,fully described; I with a portionof the envelope -disposed'exteriorly of the casing and the'remainder thereof disposed interiorly of the casing and immersed in the v1 body of cooling and insulating material 9. A 90 cooling radiator 17 is secured to the terminalrof Ythe anode 16 which extends exteriorly of the evacuated envelope and is accordingly immersed in the cooling and insulating medium 9 for the purpose of vtransmitting the heat generatedV during operation of the tube to this latter medium. A low tension transformer 18, having a primary `winding 19, which may bev connected Ato the envelope and casing.l

One end' of the high tension secondary'winding. 8 is connected to the anode terminal, which constitutes thejradiator 17, by means of -a conductor- 25.disposedv Within the casingandl the 110 `the cooling andv insulating material. generated during operation of the tube is transremaining end of the high tension secondary 8 is suitably connected to the metallic tank 5 through a conductor 26. The high tension circuit for supplying discharge energy to the X-ray tube is completed by means of a conductor 27 which connects the casing 5 to the cathode heating source 20.

In the operation of my unit a control stand is normally employed containing the switches which connect the primary windings 7 and 19 of the high and low tension transformers, re# spectively, to the commercial source of`supply. 'Ihe low tension cathode, heating transformer may be an integral part o f the control apparatus separated from the shockproof unit as 'shown diagrammatically in Figure l in order to reduce the weight of the unit itself. -Howev'en-should it be preferred this transformer may be placed within the casing 5 and immersed in the cooling and insulating medium in the same manner as the high tension transformer. In'supporting the X-ray tube to the container, as shown in Figures l and 2, a ange 28 of a 'suitable material, such for example as that of the casing 5, provided with a laterally extending frusto-conical portion, surrounds the envelope 14 adjacent the cathode.` The smallest internal diameter of this frusto-conical portion is substantially equal. to that of the diameter of the envelope and increases in diameter toward the base'lor collar portion of the flange 28.

A'suitable oil resisting cement 29, having a Vcoefficient of expansion simulating that of the Vitreousenvelope 14, is vdisposed'in the space Vbetween the envelope and the frustoco'nical portionA of the flange and .unites the two rigidly together thus making the ange an integral part of the tube. The tube is then secured tothe casing 5 by suitable fasteners, such as studs 30, extending 'outwardly from the casing and adapted to pass Athrough openings provided'in the flange 28 with the latter rigidly secured to the casingby nuts 32.' This construction allows the ready removal of the tube for replacement or repair without disturbing any other portions of uthe apparatus. In'order to Vmake the connection of the ange to the casing oil tight I mayv pro- Yvide a'suitable gasket (not shown) or run a thin film of solder or othermetal around-the ledgeof the flange where it contacts the casing.

` iilterand affect the qualityv of the X-rays generated. Theremainder of the enevelope 14 together with the cooling radiator 17 is disposed interiorly -of the casing and thus immersed in The heat mitted to-the cooling and insulating medium 9 through the walls of the envelope as well as by the radiator 17 resulting in effective cooling and the vusual eiiicient operation of the tube.

Moreover, `the high tensionterminals and all connections carrying a potential above ground, such forei'rample as "the conductor 25 and the anode terminalV constituting the radiator" 17, are immersed in the cooling and insulating medium having a higher dielectrio'strength than air. ,This enables the spacing' between Vthese highpotentia1 parts and the grounded casing 5 and cathode terminals 23, 24, between which is the full potential of the secondary winding 8, to be considerably reduced over that required for an X-ray tube operated in air with the same applied voltage. Accordingly the X-ray tube itself may be ofreduced size as a lesser spacing is required between itsrespective terminals.

The modifications of my invention shown in Figs. 3 and 4 differ from that just described merely in the manner of supporting the X-ray tube from the casing and in all other respects thek construction and arrangements of the various partsare identical. In Fig. 3, I have shown a skirt 33 of the same vitreousmaterial as the envelope of the X-ray tube 14 rigidly aiiixed to the latter and forming a part thereof. This vskirt extends from the point of connection to the envelope 14 slightly outwardly and upwardly to'form a ring or collar surrounding the envelope .having a slightly vgreater diameter thanV they latter.

The ange 28 is in this instance provided with a slightly taperingredge 34 about the pe.- riphery of the laterally extending portionthereof whichis joined-to the largerdiameter portion of the skirt 33. These elementsareunited at this point in a manner well known to the art to form a metal to glass seal which is absolutely oil tight thus dispensing with Athe necessity of an oil resisting cement as in the modification prey,

viously described. The flange 28 vmay then be secured to the casing 5 in the same manner as stated relative to Figs. l -and 2.

in Fig. 4, I have shown still another form of ico my invention for. supporting the 1 X-ray tube tolthe container. Inl this particular fernbediv.ment I surround the X-ray tube enveloperwith a metal lband 35 or. make the same anintegral partfof' the` wallrof the envelope byvuniting the glass envelope thereto asis wellknown.

This metal'band 35 isfprovided with a laterally extending ring 36 ,surrounding the band, which is eitherrigidly secured-thereto or maybe a part struck up from the band itself.

-The ange. 28 is'fprovided, in this instance, with a laterally'extending portion comprising a exible metal collar '37fwhich is joined togthe ring 36 and consequently tothe tube-,envelope -14 forming. therewithV an oil tightseal. VThisreduces the .rigidity between the tube and casing and'absorbs, to a'considerable, extent, any jars or shocks to which thetube-may 4unavoidably be subjected duringshipmentfvor operation of the apparatus. Moreover, due tothe yieldable construction ofthe ange 28, displacement of 'thetube in a longitudinal direction occurs following any tendency of the-cooling and insulating material to, change its yvolumetric capacity due to rises in temperature.

In View of the foregoing it readily becomes ob-v vious to those skilled in the art that I have provided ashockproof X-ray unit that is rugged and compact and inY which thepossibility of an operator or patient accidentially contacting any high voltageparts is entirely obviated. Morei immersed in the cooling and insulating medium the' portion of the envelope through which the X- raysemanate is disposed exteriorlyA of the v'casing'and' medium thus preventing the ltering ofthe X-rays or in any way affecting the quality of the X-ray projected upon a patient or a sensitized lm. Y Y

Having described several specific embodiments of my invention I do not desire to be limited thereto as various other modiiications `of the same may be made Without departing from the spirit and scope of the invention as set orthin the appended claims.

What is claimed istV '1; .In `an electron discharge apparatus, the combination or a casing provided with a source of high potential electrical energy therein, an insulating and cooling -medium enveloping lsaid high potential source, an electron dischargev tube formed at least in part of avvitreousy hermetically-sealed evacuated envelope havingan anode anda filamentary cathode and adapted to be energized bysaid high potentialsource, and Vmeans Vfor supporting said discharge tube by said casing with the greater portionofrthe envelope of said tube immersed in said cooling andv insulating medium and the remainder thereof disposed exteriorly of said casing, and'said means forming an oil tight sealv With said envelope` and said casing.

2. In an electron discharge apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high4 potential source, an electron discharge tube formed at least in part of a vitreous hermetically sealed evacuated envelope having an anode and a lamentary cathode and adapted to ibe energized by said high potential source, and

means for supporting said discharge device by .said casing with the greater portion of the envelope of said tube and its anode terminal immersed in said insulating and cooling medium, and the remainder of the envelope of said tube and its cathode terminal disposed exteriorly of said casing, said means forming an oil tight seal with the envelope of said tube and said casing.

3. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube formed at least in part of a vitreous hermetically sealed evacuated envelope having an anode and a filamentary cathode and adapted to be energized by said high potential source, and means interposed between the envelope of said tube and said casing, for supporting said Xray tube by said casing with the greater portion of the envelope of said tube immersed in said insulating and cooling medium and the remainder thereof disposed exteriorly of said casing, and for forming an oil tight seal between said tube and said casing.

4. In an electron discharge apparatus, the combination or" a casing provided with a source or" high potential electrical energy therein, an insulating and cooling medium enveloping said Vhigh potential source, an electron discharge tube having an hermetically sealed evacuated envelope formed at least in part of a vitreous material and provided with an anode and a iilamentary cathode adapted to be energized by said high potential source, and means for securing said tube to said casing to form an oil tight seal therebetween with the greater portion of the envelope of said tube projecting into 'said casing and immersed in said insulating and cooling medium and the vremainder thereof ldis-V posed exteriorly `of said casing.,

5. In an electronv discharge apparatus, the

combination of a casing provided-with a source of high potential electrical `energytherein, an-

formed at'least in. part of a vitreous :material y and provided With an anode and a'lamentary cathode adapted to be energized by saidlrigh potential source, and anoil tight flange secured to the envelope of said tubeand engageable withv said casing to form an oil tight seal therebetween fand 'for supporting said tube with the.

greater Vportion of the envelope thereof disposed'interiorly of said casing in saidbody of` insulating and cooling medium Aand the remainder of. said tube .disposed exteriorly of said casing. v

6. In an X-ray apparatus, 'the `combination'l of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, lan X-ray tube having an hermetl ically sealed evacuated envelope formed at least in part of a vitreous 'material' and provided with an anode and a filamentary cathode adapted to lie-energized by said high potential source, and means forming an oil tight seal with said envelope and said casing, and v:forsupporting said X-ray-tubeA by said casing with the greater portion of the envelope of said tube and its anode terminal disposed interiorly of said casing in said body of insulating and cooling medium and `the remainder of said envelope and the cathode terminal disposed exteriorly of said casing.

7. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube having an hermetically sealed evacuated envelope formed at least in part of a vitreous material and provided with an anode and a iilamentary cathode adapted to be energized by said high potential source, and means secured to the envelope of said tube and to said casing to form an oil tight seal therebetween and for supporting said tube With the portion of said envelope from which X-rays emanate located exteriorly of said casing and the remainer of said envelope disposed interiorly' of said casing and immersed in said cooling and insulating material.

8. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube energizable by said high potential source having an hermetically sealed evacuated envelope formed at least in part of a vitreous material and provided with an anode and a i'ilamentary cathode therein and an anode stein, a heat dissipating means carried by said anode stem forpdissipating heat from said anode during operation of said X-ray tube, and means forming an oil tight seal with the envelope of said tube and said casing, and supporting said X-ray tube with the portion of said envelope from which X-rays emanate disposed exteriorly of said casing and the remainder of said envelope and said heat dissipating means disposed interiorly of said casing and immersed in said cooling and insulating medium. v

i9. In an .X-ray apparatus, the combination of a casing provided with a source of high potential energy therein, an insulating and cooling medium venveloping said high potential source, an X-ray 4tube venergizable by said high potential Vsource and having an hermetically sealed evacuatedlenvelope formed at least in part of a vitreous material with an anode and a ii1amen-` tary cathode therein, a flange adapted to be secured Ato the envelope of said tube and to said casing, means jfor securing said flange to the envelope of said tube comprising an oil resisting cement having a coefficient of expansion similar to said envelope, and means for securing said ange to said casing to form an oil tight seal therewith and to support said tube with the portion of said envelope from which X-rays emanate disposed exteriorly of said casing and the Aremainder of said envelope disposed interiorly of said casing and immersed in saidy insulating and cooling medium.

10. In an X-ray apparatus, the combination of a casing provided with a source of high potential energy therein, an insulating and cooling medium enveloping said high potential source,

an 4X-ray tube energizable by said high potential source having an hermetically sealed evacuated envelope formed at least in part of a vitreous material Vand provided with an anode and a filamentary cathode therein, said envelope having a skirted portion contiguous therewith of the same vitreous material as said envelope,

Lee'aosiv a ange `secured ,to the skirted portion 'of said envelope and forming therewith an oil tight seal, and means for securing said Aiange to said casing to form an oil tight seal and to Support said tube with the portion of saidenvelope from which X- rays emanate disposed eXteriorlyV of said easing and the remainder of said envelope disposed interiorly of Vsaid vcasing and immersed in said insulating and cooling medium.

11. In an X-ray apparatus, the combinationlof a casing provided with a Vsource of high potential electrical energy therein, an insulating Yand cooling medium enveloping said high potential source, Van X-ray tube energizable by said high potential source having an evacuated hermeticallysealed envelope formed at least in part of a vitreous material and provided with an anode and a iilamentary cathode, said envelope being formed, in `part of metal and provided` with a flange flexibly secured thereto and forming an oil tight seal therewith for the purpose of preventing shocks from deleteriously ailecting said tube, and means for securing said ange to said casing to form an oil tight seal therewith and to support said tube with the portion of said( envelope from which X-rays emanate `disposed exteriorly of said casing and the remainder of said envelope dsposed interiorly of said casing and immersed in said insulating and cooling medium for cooling said tube during operation thereof. v

Y MONTFORD MORRISON.

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