US2614528A

US2614528A - Dry spray equipment

Info

Publication number: US2614528A
Application number: US24402A
Authority: US
Inventors: Britcher Charles William
Original assignee: CRAIG CORP
Current assignee: CRAIG CORP
Priority date: 1948-04-30
Filing date: 1948-04-30
Publication date: 1952-10-21
Anticipated expiration: 1969-10-21

Description

DRY SPRAY EQUIPMENT Filed April 30. 1948, 4 Sheets-Sheet 1 I JO w ATTO R N EYS Oct. 21, 1952 c. w. BRN-CHER DRY SPRAY EQUIPMENT 4 Sheets-Sheet 2 Fi led April 50. 1948 lNvENToR @Aanleg m'zzzamfchef ATTORNEYS Oct. 21, 1952 c. w. BRITCHER DRY SPRAY EQUIPMENT 4 Sheets-Sheet 3 Fi led April 30, 1948 Slg/M' '.Oct. 2l, 41952 Q W, BRN-CHER 2,614,528

DRYv SPRAY EQUIPMENT n Filed April 30. 1948 4 Sheets-Sheet 4 ATTORN YS Patented Qct. 21, .1952

@misma y what requires :mi f gl nmel wish- .a mltiple outlet fitting,

Y' as-kefo 11216 "between me munication to the interior of the dehydrator tank The bottom of the dehydrator ,.tank is' also provided with a pet cock 43, the mounting nipple 44 of which is threaded into a hollow plug 45 may be viewable through sight glass 8 I', the upper threaded into an opening in the bottom of th'e" dehydrator tank 35.

held in place as by soldering.

The deny/crater tank so uesirabiy is cned with f f a drying composition such as silica gel of the tell- The bore of plug 45vhas ag; seat 4t on which is positioned a screendisc 41,

tale type and is also desiralolyl provided witha sight glass 43 comprising a bushing 49 threaded into an opening in the wall of the dehydrator tank A 3G and having a glass disc 5| ainxed by cementing or gluing on a seat 52 at the inner end ofthe bushing. Y

A bushing 33 threaded vinto an opening at the top of tank 3|). has a tapped bore 54 reduced to form a seat 55 on vvhich'a mesh screen disc 56 is placed. The screen is retained on Vits seat by a lock sleeve 51 threaded into :bore 54 and which has lateral openings 58 aording communication with theinterior of the dehydrator tank 3J.V Y

From the top of tank 30 a pipe159 threaded into bushing 53, leads into solenoidvalve 6| which as it is conventional in constructionwill. notv be described in detail. n l Y,

Valve di which whendeenergized is in closed posi-tion, is connected by cross conduit 62 and pipe t3 to pressure regulator .E4 the latter having a pressure gauge 65 associated therewith. From regulator E4, pipe 65 leads to `needle valve 61 which has a nipple 38 threaded into the lower end of the bore 69 of air inlet plug 1|. The latter is threaded into an opening at the bottom of spray tank 24 which also has a drain plug 12 therein,

In order to form a cloudofpowder in'the'tank, stationary means are provided to directa 'stream or jet of air into the powder in such manner as to violently agitate the same. Desirably such means are in communication with the air inlet' 1| and have one or more lateral outlets abovethelevel'ofl the powder in the tank.y f

In a preferred embodiment herein shcw'n,;a vertical air tube 13 is provided,` extending the major part of the height of saidl tank and thread'- ed at its lower end 14 into vthe upper` end 'of bore icfinletplugll. 'Y

The upper end of tube13 hasaf-ttingfl/E- threaded thereon, each laterally fextefnding'arrn 16 of which has threaded therein =a substantially L-shaped air agitator tube-11, thedownwardly turned portion 13 respectively of eachof which is provided with a nozzlev 19 and isy curved inwardy, said portions'l each being inclined from the vertical. such that Veach nozzle19, which has an aperture therein oapproximately .067 inch, will direct a" jet of air at a downward angle of about 38 tod() degrees across radii of the tank toward the'opposing surface of the wall thereof and as; the nozzles n 'i9 are'displacedfrom the centerof the tank,`the

Preferably the' curvature of portions 18v` isY jet of air will strike the wall atsuch an angle as l ranged to whirl the air in a counterclockwise direction, the mixing action being the same.

The spray tank 24 is provided with a sight glass 3| identical to sight glass 48 in the dehydrator tank S, comprising as it does a bushing 82 threaded into an opening in the wall of the spray tank 24 `and having a glass disc 83 affixed as by cementingorgluing on'iafseat 84`atithe inner 'end of the bushing. 'Y f- /In order that the interior of the spray tank ypart of thespray tank is desirably equipped with an electric lamp S5 threaded into a socket 36 af- 'iixed in anopening inthe tank 24. The lamp 85 is constantly illuminated While the device is operating so that the v'powder cloud set up in the spray tank 24 may be inspected to check on lthe operation of the machine.

v To bviate'the obscuration of the sight 8| from the heavy deposit of powder thereon incurred in operation Yof the machine, cleaning means are provided vfor .the-sight.y lSuch means comprises a rod- 89 extending'through a bearing 9| threaded in an opening in the v wall of spray tank 24 below sight 8| thereof. The portion of rod'89 extending inside the tank is upwardly bent as at 92 with a flatangle end 93 -parallel to the face of sight glass 83. screws and rubs over glass 83 when rod` 89 is rotated byaknob 95 affixed to the outer exposed end of rod 89. A pin 96 transversely` through an opening in rod 89 adjacent the inner end of bear--Y ing 9| coacts with va pair of pins 91 ailixed on the inner end of the bearing and extending laterally inward therefromv tolimit the rotation of rod 89.

Mounted at the top'of the spray tank 24 is an outlet head |99 comprising a valve stem bearing I avalve top I I2 l and a valve base I I3retained together by'screws I I9 'extending therethrough into a threaded openingl 041m the top of the sprayI tank. A stop plate |54 is also provided secured :to valve stem bearing III by screw'l ID, a tight seal being maintained between the stop plate IEA and the valve stern bearing I by gasket |58. Base |3 has an internally threaded stemIId extending slightly into the interior of spray; tank 24 and an inlet sleeve I l5 is threaded intostem H4. Sleeve I5 has a bore I I6 leading into stern I 4 and a plurality Aof openings I Il are providedextending through sleeve i5 into-bore Hethereof. :The valve stem bearing II has a bore-H9 extending verticallyv therethrough, countersunk at both ends thereof as at |2| and |22, and a transverse bore |29 lextends therethrough and intersects said vertical bore H9. An annular recess |25 is provided invalve stem bearing III coaxial with the .narrow end of bore |23 and of larger diameter than such end. Atapered feed valve sternfIEi nts into the correspondingly tapered bore, y|23 and has a reduced threaded end |21 whichextends beyond recess I 2li. YA laterally eX- tending1 pin |29 is aidxed lin the `vshoulder |29 formed by reduced end |21 and fits into a correspending opening |32 in a valve stem washer |3| positioned in recess |25 andretained therein by a nut |33 threaded on end |21, the nut serving to retain the valve stem I 23 in bore |23.

Yalvestem I 26 has -a bore |35 extending transversely therethrough and a transverse Abore |36 at. righty angles to bore |35. Valvebearing isvalso provided vwith a transverse bore 31 extending into bore |23 thereof and having a socket |38.in which is threaded the nipple'end of a cross pipe |39 carrying a T-coupling |49 `at its A lbrush 94 is secured to angle end 93 by' y-lueinthe spray position .withngbore t3-5 :thereof ...bore .|36 n`willchefaligned with .the upper portion f bOI'e' H .9 .thus cutting-off;communication with the ,Spray -ftank l'2 4. and fperrrl'ltting vairrtofheloloufr'i s ltlzlrough-the -outlet :head :.llilinr-tl'le maurleriherematter described.

-.:elve,top. l |12 thas .af-.here 151. therethrough eountersunk.ontits-ioottomestati!581 and in imitapositionfto the.eountersunkportion Ritter-:form .farmixleg .chamberto-.facltate mixing of :ima-nd postuler.' -A booster fitting .ltwhichzis'wprefeb- 'ably..cast:irom 'bronze...has al vertical `here .L52 therethrough, :threaded ;at .flower .endV oinzza nipple .r5.9 Y.in -turn i. threaded. into the nhere '1.1.51 igf..the.ualve :top -z 2, .Fittngl 6|. also has .avhore talextendihg at.;i=tn.angllofrv approximately '20 .degreesfinto .bore .tzznearsthe V.upper :endoffathe ittinggandhas a-threadedlower end Hill to which ,is .connected .1a. bushing .I 6.5 holding a tube 1.65, one .end il 61 '.of which extends :through 'bushing A|64 .zand'hore `|63 .into bore .|62 and .thetother end ..|10 of-whchis connected'to nipple 11.68 of .boosterneedle :value |69 fconneeted It@ .tlle'zupller .end :of :Tr-coupling |43.

.Threaded on the upper-'end of 1the'Iloooster.aitting |6| is .dvidinghead which, as shown in 7, .illustratively has :two'topenings |12 therein, .ineaeh .of which I.is .desirably threaded .a double powder feed .113., provided with shuteoi hand .cocks |14 for :each yoi' l the outlet lfcoumille'fs |15 thereof, to turn .on tand off the air'fandpow.- .der stream. In thefembodiment of'Fig.' ilvorlly .one .outlet Aeoupling .-i-s utilized; Ithe?aothers rhe- .ing shut 01T yhy handaeocks |14.

. A ySpray tube 23 desirably :extend-ing horizon tally betweenhrackets -l'iarld directly oi/export, if desired, .under the usual horizontalwsllirface to be sprayedfiis .fedfthrough distributorpipe a -221 from the respectieve fopen outlet :coupling -rl El 5.. Distributor .pipe 22 -leads yirito a Y iitti-njg |116 .having v an air relief'yalve ITI which is conneeted .to the `feeder inlet .end of .Spray tube .23.

'Ina preferred embodiment of the '.spray-,:tlrbe 23 shown in Figs. V1 and 9, theLlength 'thereof iis y.corrugated,fas shown, "along the effeetive'iwidth .Qfitheaeurfacefte 'loei.c '.\',a`.ted. "These eorrugatorls are-.desirablytuniform y'in length Landheight.' The acorrugations are -preferably -of l'such height that the crests thereof in 'thewal1-of the-h'ore'vare 4 substantiallyaligned'iwith thef treuefhs`thereof at' fthe 'zdian'ie,tr-icallyA opposite #wall jiportionf'fas ashown'fby Adotiand A'dashli'nesih f9,. Y y

`The spraytube- 23 has r sprayapertures IITI'S that are "equidistantand Aat' `One'side .ofthetub'e 23 :and fir-lv linear alignment. 'lili-ey .areillrefei` ably not .at the verytrough o,f"=theeorrugations, but veach aperture ls'spaeed ,slightlyibehlrrdisaid trough, Ythat is; 'somewhatllarther friolrl .the tube ".outletzthan is' the bottom .of .lzhejtroueh., 'T'Ihe .epray- -aper'mres are preerahlyinelined so '.that they slope downwardirom the boreolthe :spray "tube 'iand ioutward in 'direction .opposed .to ofthe 'air'.iiow therethrough.

ilustres. .begifnnmget the 'reed fendl :ofithe -zthefleng-.th -;thereoff:due1.-to .its escape `from them)- ;ertureftherein, :there will :be a .tendencyfaforn the *powder*-` to'; rush fpast fthe .aperture fclosest to the feed :end .In Sorcier... that .the output. .ofzgpowder from each aperture beeubstantially.thelsame .the spray 1 aperturesfare rdeeirably `erarialiated in eize', .heine .largerfat lthe. feed :or inlet :end .oiffthe eurer .'tzube-.iLIluStlatiYeIy ...0&5 inch :in diameter and/.decreasihgwto .approximately .-03 11i-heh. 'in faepray :tube having '1a spraying .ieriethfelfv =60 .ltuloe, there will be ten..,|.16.5ff.ii1ch apertlires,` .,hirteen 503.6'. inchia-perturesfe d eig-ht. ,0.3.1 `inchallertures. Thus asitheapowder rueheshy :the larger-dahertures vat. the feed erid of :the spray-tube substanf itiallythefsameuuantity willeseope therefrom-vas :from the. smaller apertures at :the opposite .end of, the .spray tube.-

Each of the apertures |=|=9..i s preferably in iadvanee vof thertroughss-.and is Aflooredfirlto the tube afterthefsamehas been corrugated. Pref.- eral-bly the exis .of...t he .tube is. inclined. slightly :to an' .ane-le of about' 3/ deereesiorsuch drilling-.so thaiathe .vertically i rected drills will bore the apertureatedownwardainelination. l Y v .erder.toprevent backing upeoipowder and `air inthe spraytube which-might elog'the same. a-breatherl provided' the operation .of-which will be. hereinafter desc'iribed in detailwglvhe .breather .comprises-.atop cap 10|. threadednfon the open end of a'pipe |8'2 connected totheend of .the .spray k.tube .2.3, .An Aouter shell-.|83A is .threaded Einto cap |B.| Yso as to hang vdowmilfard therefrom. -.A .loottomrap 48A having a tube .13,5 threaded into eurngoeriirigV |86. therein, is 'threaded von. theLbottorn .end .orsheill L83.. vThe 'tubey liS lof .suchleneth as `to extend url-.Ward to. nearly' 'the opening 1|.6.0.in.to p cap '|.8..|. andis plugged at 'its ,upper .end asat .|81 .andprov'ided with an apervture .las .through the wallthereof extendinglirlto .the `hereofthe tube i185.

In order to energize the solenoidfyalye il .and the lamp ,85 during .operation .of the ,devicathey are .connected :in Iparallel withl main `2:05 which .has awiteh '20.6 in .circuit therewith. ,A 4,m,elfeufry switch 2011s .also provided .under .control .ofthe 'more.or..less remoteemeehanism whenlthelslr'ayf 1 amid .ualve .6lwill @be energized Land .open .andthe ,lamp v'vlll'loeilluminated.v '.Compressed airfwill .passiromL-the source of .pneumatic .pressure v (not shown) to lnletgflttingl which .dschargeeirlto ,aiulter .2 1 :Whereltheair .will be oleanedahd their passy through `pipe Yfit! .and-presume regolatori] normally .set at .50` pounds .as indicated eri-gauge .3.2iA .Eromthe pressureregulator theair will .pass thm-ugh -cross pipe 33. and shuteo ...cock 3.4 through meshscreene which-prevents any" hriis orioreign matter.. p.assirlg therethrough,.ihtothe .bottom ofthe .dehydrator tank 30- The air after being dried in its passage through the silica gel in the dehydrator tank will `pass through mesh screen 56 to remove any particles therein and then pass through pipe 59 and the open solenoid valve 6|, through cross conduit 62 andpipe 63 to pressure reducing valvev G4 where thev pressure is set to from 2 to 5 pounds as'indicated on gauge 65. The air then passes through pipe 66, open needle valve 6l to the spray tank by way of the bore 69 of Vair inlet plug 1| 'and thence through air tube 13 and out of apertures 'I9 of the agitator tubesl 11, thus delivering two currents of air 'which will be whirled in aclockwise direction at a downward angle, as shown, of about 36 to 40 degrees. 'f

vIn ordinary spraying, as in thev graphic .-art industry for example, the needle valve 61 'is kept open at all times, but in some applications where it is desired to increase the pressure ofthe air entering the spray tank 24 Without increasing its volume the size of the orifice in the needle valve 61 can be slightly reduced. f

vAs a slight pressure, approximately 2 -tov `5 pounds will be built up in 'tank 24; when valve handle '|53 is in spray positionL Withbore ||9 aligned with bore |35, some of the powder from the cloud formed by the whirling air currents set up in the tank 24 through pipes 78 will be forced through'the outlet head |09. f v

The'movement of the air will exertran effective suction on tank 24 to draw additional particles of powder therefrom through bore 5' and aperture ||1 of sleeve ||5. It is of course apparent that the greater the air pressure or velocity of the air through bore |63 of the booster tting the greater will be the amount and intensity of the powder stream propelled through the outlet couplings |15 and the distributor tube 22 to the spray tube 23 wherefrom it is sprayed on the surface being treated.

It is to be noted that in passing through the spray tube 23, the obstructions imposed by the corrugations therein will intercept some of the powder entrained with the air forced through the feed end of the tube 23 while some will be blown through the apertures |19 for the spraying action desired. The location and size of the spray y apertures hereinbefore set forth brings about an effective and uniform spray therethrough, both through those near the inlet of the spray tube and those remote from the inlet. It is to be further noted also that were the obstructions imposed by the corrugations omitted, the spray would be `far from uniform, as some holes would deliver with the diametrically opposite troughsy of'such bore, it has been found 'that the resistance'. im-

posed in advance of each spray aperture is exactly right for bringing about the uniformity of distribution. The disposition of the spray aperture |19 slightly beyond the bottom of thel trough and in the direction set forth, assures axuniform ysymmetrical spray Where the location'of such aperture elsewhere or at a different angle would lead to a spray deflected either to the right or to the left from that shown and thus render the distribution less uniform.

It willbe understood that while in general the spray apertures are at the forward side of the sprayA tube, the corrugations of whichA lie in a yhorizontal plane, as best shown in Figs. l and 9,

the plane of the corrugation mayfor certain applications be tilted downward or; rin some cases, it may be tilted upward to the desired angle yfor spraying the underface of a sheet or plate passed thereabove. The length of the spray tube of the present invention may be extended obliquely or even vertically for certain special applications as, for'instance, the coating of a wall or a silo, and the distribution of powder'is found to be thoroughly uniform in any of `such applications.

It will also be understood that two-"or more of the spray'tubes may be arranged in parallel and in slightly cascaded relation for great precision of powder distribution. ln such case the outlet head of the device would be equipped with a sucient number of outlet couplings for dis'- tributor tubes to supply all of such spray tubes.

When the air and entrained powder that is not discharged through the spray apertures |75 reaches the end of the spray tube they will enter the outer shell |83 of the vertical breather device through tube |82. As the air' pressure during its passage through the distributor pipe 22 and spray tube 23 has decreased from approximately 2 to 5 pounds in the tank 24 to but a negligible amount when it enters shell |83, the powder particles will drop to thebottorn thereof which is sealed by bottom cap *|86 while the air will escape through lateral'aperture |853 in tube and out of opening iSd-'in bottom cap |86. As aperture |88 is nearvthe top of the breather |80 normally no powder will escape therethrough. However, when' the powder level in the shell rises up to aperture l'a'mist of powder will be ejected from opening it in the vbottom of the breather instead or" clean air.

This will indicate that it iis time to empty the shell which is done by unscrewing the shell from its top cap. The powder thus emptied may be salvaged for re-use. f

Throughout the operation of then-spray apparatus the operator may inspect the efficiency vof the powder cloud and 'determine the level of powder in the spray tank through the sight glass to assure best operation.`

When no .further spraying is required, it is desirable to clear the spray tube and distributor tube of powder remaining therein as exposure of the latterto the atmosphere for any length of time may result in clogging and contamination, especially if the powder be ofhygroscopic character. To this end, valve handle |53 inthe outlet head is moved from spray position to blowout position. Valve stern |26 lwill thus be turned in its bore |23 so that communication to the spray tank 24 will be sealed land bore |35 of stem |26 Vwill be aligned with bore |37 of valve fitting to providel a passage for the compressed air which is under a relatively high pressure of 50 pounds from the compressor (not nosed;

andere showni-iwhich f path `ofithefa'4 Liprpe 29 through-pressure regular@ it 'and crosse-pipette intoiidehy'dr'atorl' tankwSU omthel outletjend ofi'saidi tankthroughi ipe-5592 vailve cross pipe 62, pipes 69, and |39, throughffbores |31; -ISf-and I 3 6 intobore |62y ot b'oosten1fltting IS'I their 'tnrougl'r'distributoripipe.1izz-f'andr spray tube` "3. Thus the distributor 'fpip landespray "tuba-#will behlown 'clearJ l'of' powde "forcing i such throughsightglass-48pv f i :When the; gel.- ;isibl-ue',xthes'air passing' here-1 throughctoward the Supper: end.' of: theadehydrator tank.' .is .-dryt. 'and'.r the?v fdehyldrator: isY functioning prop'erlyi .rWh'en:I the. gel-iisfapinfl'ri.y or salmoni-:in color'glit is; saturated to-aboutflO pen cent,.rel ative .humidity and... should: be; replaced 4:xvii-hice, refill fof" activated iflblue) Egel. y.f;Remo'val.{or}the bushing 45. allows theasaturated gel-.tosdrain from the dehydrator tank. When theibushingf. 45.-'has beenreplaced with shuteo-.i'c'ocls:431.closed, .the sight?- .glas's 43,.' is :removed fori refilling the; dee hydrator-" f" f 1 Y w In. order to replenis-he` .thea-.supply `poi/voler.

yin..fthe-spray `tank'. 24;, ia :powder supply tank'. v.99

isadesirably. mountedI adjacentato andi at.V ahigher levelth'an spray. tank.124,.:byumeansifoflazbracket lillnconnected to fthe. bottomifo the .lpowderctahk 99fby= rscrew 1-|D2an`d= to theisde..wallotztliesprayv tank 1. :by screws ll .'Ifh'ez, top f of theip'owder supply tank Y( :lo'sed'fb'y 'a :cover-'1: plate'. :|081 fremovably' threadedf'threon :at A101'.- Communie tion .'-f'islsestablished between hey powderrsupply tank ..99f-5andrthe. vspray,'talnkii1241' by meansI pi i a nipple: :1 0-5 'Lhavng A.-a=1valve' |ll|fitherein.- :To ...re-v plenish. the.` spray tank;theopowdensupply .valve |06;t .isrnpe'ned.-,allowing.i ,the c'ompressed; aimirom the fsprlaaf.-` .tank `l249.130: pass..l into",fsupply:I tank 2:99 which had, :prevouslyxheerr lled. with".y powder; Inasmu'chrzas tank x99. .hasn-no: outlehrexcept'. that provided by valverlll 6 'air pressure :will ib -built up therein. .f f i.; .v y

In order to,break th'e/ crcuititoathe solenoid valve 6| thereby causing the latter to close and shut off the air supply'tof *thefspray tank 24, a switch button 208-.is provided-inseries with said solenoid valve 6|. With therbuttonf depressed and the valve deenergized andclosed the air in the spray tank 24 will' thereupon escape through open outlet head=| |l9- causing thelprese suregin tank 24 to fall. 1-

he Vgreater.pneumatic lpres's'ure now "e sting insupply tank 99 will leffect expulsion 'o'fpbwder therefrom through' V'open' Vvalve "i 06 into' @spray tank 24'. By alternately press-ing and rel ing the button "208 'the' process of' transferring p der fr' 'thesupply tankto' th'espray tanks ntf 'eduntil the llatterv is Jhal'fynlledx th o'u'gh si'e'ht'glass 8|. ValveL-IUB is th procedure `eneroies. the operato replen'ishthe 'spray tank wit' powder Jfrbrn'the supply tank 99 even while the spray is operating. However in cases where it is desired to feed large quantities of powder the above method of supplying the spray tank 24 would require too much manual attention.

Toremedy-this -i'orJ industrial dusting operations', :an automatic timer 209 is provided shown in clashes in Fig. 1. This timer, the construction'ofwhich is-vconventional and which per se forms nopart-lof thisl invention, y replaces switch 208 in thecircuit'and hence is in serieswith the soler'ioidv Valve 6|; The'electrio'timer 209'is set, auton'laticallyto r open?` andi close the solenoid valve 'approximately 1Ar'second.out of every 30 secondsto control thel feeding ofpowder in'to the spray tank 24 as above described, when normally closed button 208 iis pressed toA open thecircuit to valvel I I In the use of the automaticltimer 2GB, valve |96isi-.openedsufficiently*toi admit powder into the spray tank L24 each 30 seconds, at substantially' the rateofi usefthereof., thereby to maintain.l a `substantial.constantlevel of powder in thejspraytank.'a.... l L

. In .the embodimentfof:.thepbreatherdevice la shown :in Fig.. 12.a top .cap |8|. isprovided, threaded 'onthe open end of. pipe ,|82 connected to the `,end -of the spray tube A23;V A cylindrical container: I|`83-.,is; threaded into .cap I1.' soas` to hang downwardly therefrom, and an` air relief valve 2fi0is positioned on. ,capA 18| incomrnunicaE tion .with the interior-of; container |83'.

, Thus when.:the Adeviceisl in; use, the air and entrained powderthatis notdscharged through theepray apertures |1'|,9,wher1; they` reachrthe end et' the spray-tube 23, will enter the; container seit of the yerticalbreather. vdei/ice |80 through tube: 182;., As, the. air pressure during its passage through the distributor pipev 22 `,and spray tube 23- hasldecreasedas hasibeen heretofore; described,

the-'powderywllqfall tothe sealed; bottom of the container |83.' and remain therein while the air willrescape.throughlair relief valve Zilli). Asthe I :'In-y Fig-10,thefdevicerhereinsrshownesapplied to ahust;ichaxnher.;4 |9|fonsprayingnmaterial `in motion. In, thisiapplication :the four outlet 4cou-l Y plingsf-.lflff are: utilized...eachp'connected,respec-v tively bya'riistributontubei 92 to an;.ejectorg pipe |83 igslidably: mounted; in; :a bearing. |oushingv..4 |94 afxedzto: .the` side.; .wall l of .the dust;- lchamber |91?. The .ejector :pipesnl Maarre. mounted vvin pairs: ofi'eachisidewallf|.95rsofasfto sprayi powder `over the-webfaot :material fllxwhich:moves 'longitudinallyrthrough :the ichamber 19| Thev .slidable pipes may be adjusted laterally to accommodate fordifferentwililthslofweb@v f im? .Figa-'#11 'therdeviceiisgishown asi applied tov a,:new:hirie v 91 tor linanufacturing. extruded tubin'gillstratively o'f rubber'. this` machine itse'lif is: vconventi'onal .andiorms l per sev no part of thisinventifin,A it `will ln'ot'be describedin detail. One' of thdoutlet -couplings i 'lfisv l*connected by -distributor tube |98f'ft'olan ejector 'pipe |99, theI"nozaleendv Zul-fof `Vwhiclr-extend s-#intothe bore of theHeXtrudedf-tubing as -it' emerges `,f-rovrnlthe Inachine;A lif'a'iid dust'sftheinterior yofl such tube, therebypreventing the 'walls v`of``the same from sticking together if they should contact each other.

It is of course to be understood that the applications of the device herein shown are merely illustrative of the many uses to which it can be put and are not intended to limit such uses in any way.

As many changes could be made in the above construction, and many apparently widely different embodiments' of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A dry powder spray equipment comprising a powder spray tank having an outlet and an-` inlet, means for delivering compressed air into said inlet, one or more fixed nozzles in said tank connected to said inlet and each positioned to direct a jet of air across radii of said tank and downward into the powder in said tank at an angle of less than 90 degrees, to whirl said air in an oblique path thereby to stir up a cloud of powder in said tank and means associated with said outlet for creating a suction in said tank whereby powder may be entrained from such cloud for delivery to the surface to be sprayed.

2. A dry powder spray equipment comprising a tank for dry powder, having an outlet at the top thereof, an upstanding tube in said tank rising through such powder and connected at its lower end to a source of pneumatic pressure, fixed air agitator tubes aiiixed to the top of said first named tube and extending substantially laterally therefrom, each of said air agitator tubes having a curved, downwardly extending portion having a nozzle at the end thereof, each of said downwardly extending portions being tilted from the vertical so that said nozzles may direct jets of air across radii of said tank downward toward the bottom of the latter at an angle of less than 90 degrees to whirl said air in an oblique path, thereby to stir up a cloud of powder in said tank and means associated with said outlet for creating a suction in said tank whereby powder may be entrained from such cloud for delivery to the surface to be sprayed.

3. Powder spraying apparatus comprising a tank for powder, means connecting said tank to a source of compressed air, means in said tank actuated by said compressed air for stirring up a cloud of powder in the upper part of said tank, an outlet head on said tank and normally in communication therewith, means connecting such source of compressed air directly to said outlet head, and a feed valve in said outlet head shutting oif communication from the tank therebelow and directing the air blast through said outlet head.

4. A dry powder spray equipment comprising a powder spray tank having an outlet head at the top thereof and an air inlet at the bottom thereof, a tube connected to said air inlet and extending upwardly into said tank, means for delivering compressed air through said tube, means to dry such compressed air before delivery to said tube, air agitator tubes affixed to the top of said rst named tube and extending laterally therefrom, each of said air` agitator tubes having a curved, downwardly extending portion having a nozzle at the end thereof, through which the v12 compressed air delivered through said air agitator tubes may be expelled thereby stirring upa cloud'of powder in the tank, and means associated with the outlet head for entraining powder from such cloud for delivery to the surface to be sprayed.

5. Powder spraying apparatus of the character described comprising a tank for dry powder having an inlet thereto at the lower end thereof, means connecting a source of compressed air to saidinlet, means to dry such compressed air before passage thereof through said inlet, an outlethead at the top of said tank and normally in communication therewith, a` tube extending upwardly in said tank from the lower end thereof and connected to said inlet, air agitator tubes affixed to the top of said last named tube and extending laterally therefrom, each of said agitator tubes having a, nozzle, the compressed air delivered through said nozzles thereby generating a cloud of powder in said tank and building up pressure therein to force powder from such cloud in said tank through said outlet, means connecting such source of compressed air directly to said outlet head and normally not in communication therewith, and a valve in said outlet head to close off communication from said tank and provide communication from saidrlast named means thereto.

6. Powder spraying apparatus comprising a tank for powder, means connecting said tank to a source of compressed air, means in said tank actuated by such compressed air for stirring up a cloud of powder in the upper part of said tank, an outlet head on said tank and normally in communication therewith, means connecting said source of compressed air directly to said outlet head, a feed valve in said outlet head shutting oif communication from the tank therebelow and directing the air blast through said outlet head. a lamp in said tank near said outlet head, a sight glass mounted on said tank through which the illuminated interior of the tank may be viewed and means to clean the inner face of said sight glass, `said means comprising a rod extending through an opening in said tank and `iournalled therein, said rod havinga brush aixed to its inner end in juxtaposition to the inner face of said sight glass whereby when the extending end of said rod is rotated, said brush will sweep over said glass to clean the latter.

CHARLES` WILLIAM BRITCHER.

REFERENCES CITED The following references are of record in the ille of this-patent:

UNITED STATES PATENTS Britcher May 15, 1945