US2612217A - Liquid fuel burner - Google Patents

Description

Sept 30,1952 N. H. SUTTERFIELD 2,612,217

LIQUID FUEL BURNER Original Filed July 17, 1944 97 Noe/ H. sarf'efffe/d Patented Sept. 30, 1952 V LIQUID FUEL BURNER Noel H. Sutteriield, Milwaukee, Wis., assigner to The Timken-Detroit Axle Company, Detroit, Mich., a corporation of Ohio Original application July 17, 1944, Serial No.

545,234. Divided and this application Februr ary 10, 1947, Serial No. 727,604

6 Claims.

1 This invention relates to oil burning apparatus of the rotary wall flame type, and more particularly to water heaters of small capacity for smaller homes embodying oil burners of the general type shown in United States Letters Patent to Suttereld No. 2,102,763 and to Wilson and Suttereld No. 2,310 333. This application is a division of Serial No. 545,234 filed July 1'1, 1944, now United States Letters Patent 2,491,517 issued December 20, 1949, which in turn is a division of Serial No. 395,464 iiled May 27, 1941, that has matured as United States Letters Patent No. 2,360,891, granted October 24, 1944 to Milton A. Powers and myself.

It is the major object of, my invention to provide a small novel oil or like liquid fuel burning apparatus capable of eillciently burning extremely small quantities of oil, thereby to make it practical for medium sized and small homes having limited space and money for such facilities.

A further object of my invention is to provide a novel fan or air distributing device having suillcient capacity to efllciently pump the required amount of air for combustion and which is so designed as to avoid imparting suiiicient velocity to the air to interfere with ignition, even when an extremely small hearth is used, and at the same time is also designed to avoid excessive recirculation of hot gases of combustion.

A further object of the invention is to provide a novel combination of the burner fan and oil distributor wherein the fan blades and oil ilinger tubes are arranged in novel association.

Further objects are to generally improve and refine the rotary air and oil distribution features of the heating apparatus, which will become apparent as the specification proceeds in conjunction with the annexed drawings, and from the appended claims.

In the drawings:

Figure 1 is a vertical sectional view on an enlarged scale of the lower part of apparatus embodying the invention, and illustrates the hearth and distributor assembly;

Figure 2 is a fragmental top plan view of the hearth and distributor assembly shown in Figure 1; and

Figure 3 is a bottom plan view of the fan shown in Figures 1 and 2, and illustrates the relationship assumed by the oil flinger tubes with respect to the fan blades.

The improved distributor of the invention is mounted upon a suitable hearth at the lower end of a combustion chamber, substantially as disclosed in said United -States Letters Patent No.

2,360,891 to which reference is'made for further detail. f

The entire hearth assembly is carried `by a foundation or base plate 6 I, which has a diameter slightly greater than the combustion chamber.v

A layer of insulating material 64 is mounted on the base plate, andthe peripheral edge of insulaition 64 is suitably clamped in air-tight engage` ment with the lower edge of the combustion chamber. Base plateGl may be either embossed so that the hearth, supported thereby byy sup`-Vll ports 1I of equal length, will incline from the horizontal as disclosed in said Patent No.y 2,360,891, or the lower edge of the combustion chamber may be so shaped as to 11e in a iplane inclined to the horizontal, so that when the base plate is pulled into assembled relationship it will assume a similar inclination as illustrated in Figure 1. Either alternative eliminates the necessity for specially designing the hearth to drain any overflow oil to one side.

As seen in Figure 1, base plate 8| is approxi? mately centrally apertured.- Disposed in align'- ment therewith is a spacer collar 66 which supports the central portion of an apertured metalY hearth 61 in spaced relationto the basevplate, The'hearth and collar are secured tothe `base platev by a sleeve 68 flanged over the hearth and,V base plate at its upper and lower ends. The

outer edge of the hearth isprovided with an upstanding liange 69 towhich is secured a plurality of supporting legs 1l that extend through openings 12 in insulation 64 and rest upon the upper surface of the basel plate where they are` attached as by welding. I

Mounted in spaced relation to each otheron the hearth are an oil atomizing and vaporizing. Wall 13 and an air deilecting wall 14, which are` Welded to a plurality of U-shapedbrackets 15,`

and the latter are welded to hearth 61 soas to form a rigid unitary assembly referredto herein-v through the center of the hearth, preferably 25 degrees, as indicated in Figure 2. Electrode 11 is eccentrically mounted in an insulator 18 of generally cylindrical form frictionally gripped in a bracket 18a lcarried by the base plate'. The

hearth adjacent the insulator 18 is flanged up afs,

at 19 to prevent any excess oil from leaking down between the insulator and hearth.

By mounting the electrode in an igniter insulator having an eccentric aperture, and mountf trode closer toward the ame rim. If this results in swinging portion 17a materiallyaway from the desired angle, proper relationship ofrthe,parts.; may be restored by loosening a pair of nuts 19a.: and rotating the electrode -.within La clip. 19h, l1F which engages fiat portions providedonopposite. sides of the insulator. When the adjustmentnis completed, nuts 19a are then tightened. The igniter is connected to the high tension circuit of the transformer. 20

'-L'ocatedat the-low side vof the hearth` is apairz of recesses or circular channels 80 and 8| Which surround.'an.outlet port82. Outlet port 182 `communioates with apipe ffsupportedby a bracketA 84 belowithe h'eartlfr, whchleads tozartrip bucket 25 type .foff automatic .shutfoi mechanism S-,so Vthat after@ a predetermined". quantity'. of oil passes through? pipe'- 83 :the Y. bucket. will be strippedv and the lburner automatically shut off'.

. yChannels` @8 Il: and 48 l. perform; -the :highly -im portantfrrfunction` ofi trapping -any 4oilv vdischarge Which:isznotv immediately ignited at the time `the burner starts'. This preventsaow of oilfthrough pipe'into the trip -bucketfon' coldl start-i. As n previously-rlpcintedf out, the: foundation plate is d inclinada which :produces-raf -corresponding slope cl2-the hearthitoward'outlet82, sothat inthe. event yofffailure rfof ftheignition; the noverflowing Y oil Willpass thrcughfthe discharge port into pipe aandfcause fthe shut-offirnechanismto stop the burner motor. In the spastsomevdiiculty :has been, experi encedfl in having .fsmall driblets. ofy oil on; icold {on slowvv .starts dripping into. the `-drip bucketand eventually trippingthe bucket, despite theffactthatnomore thanlnormally coldstarts haveoccurred,l .and no. occasion has arisen for.' thrshutioffofthis characten This feature isi dis-.p closedfand Iclaimed in .said application Serial No. 545,234 filed July 1'?,` 1944.

Figuresfand ,-2illustrate an improved jgrille 50v structure, which; particularly when employed in combinationwithlthe distributor of the invention and shieldQi'lEjgr-eatly assists in enabling the burnerto ,operate at 'extremely low rates of oil" consumption, and combustion chambersiof 55 sm,aller,size than heretofore -regarded practical. 4*The grille ring shown in Figures 1 and 2 4comprisesacylindric'al band "of `heat resistant sheet metal'having its endsoverlapped land secured together,` and a plurality ofsimilarly shaped channelinembersi361v Each of the channel members is secured to the outer'faceof ring '85, preferably with the open sidesofthe channels facing downwardly;h 'Asfseendn-Figure 2, the channels are disposedA infsymmetrical; radiating relationship to ring 854' and are-supported approximately at their mid-portionshby the :dame rim. Thegrille 'assemblyl preferablyfmerely'freely rests upon the flarnee-rirn,A so that anythermally .induced expansionvorcontraction` of -thefpartswmay take a place-freelyy Also,A this enablesthegrillevring tobeI inverted;f so as to'face the #channels-up` wardlyi,h depending -upon the arrangement which is' foundy to'worlsfbestunderA thev particular. condiv tionl at hands The function of the grille is to assist mixing of the air and oil projected from the distributor head and to prevent the ame from lifting above the flame rim to a height where it Will not heat the flame rim suiciently to vaporize the oil pro-v jected against;1't'.. In the small' heating 'gunit illustratedpthefdistance'between the-ends' of the distributor tubes, to be hereinafter described, and the flame rim is comparatively short, approximately 2.1/8 inches. With the ame rim in such close proximity to the fiinger tubes it was found impossible-furthe older type of grilles to properly mix'ithe airsand oi'Lfor complete and clean combustion'without circulating a large amount of the hat gases, of the combustion. Excessive recirculation..is;..undesirable,-.; especially in the small hot Waterheater because there may be many numerous cold starts, particularly during the summer season, and on a cold start the effect of excessive recirculation is to cause an excessive flow of. cold, freshfaimwhich Aat high velocityfmayretardratherrthan rassist gnitions'op the. fuel.;y It.A hasbeen foundthatibyso :designing the fanas .to' produce a .limited degree iof. recirculation". with; sufficientvolumeto"y combust the .fuel and at 'suf-2 ciently' low fvelocity.1 to 'avoid (delaying ignition;` as Will'be-'described hereinafterf and providing..- the 'grille assembly fconstructedas just described: which -defiectsxth'e igasesxof `the combustion flame; behind'ithe yamecrimrunder al1 normalconrli-v tionsfland `using a shield .'11 E'to 'prevent contactt of'ftheame Withthe `lower portion of the coil;

the apparatus :performs with complete: satisface tion.

The `distributor comprisesI animator' and pump uniti 88Which.isfpreferably constructed substanl tially'as disclosed-'iii` Wilsonr and Sutt'eriieldz Pat-1 ent 'Nb.v2;310,`333.1. The unit as il1ustrated,1how'-- ever,; is supported 'by Vtwo r studsf-S-iwhich pass-l through`=brackets 98a securedto the bottom of the.- motor housing and haveY wing :.nuts 90b threaded thereon. The lmotor isl provided witha shaftV 89! uponjwhich 'is supported;- an bi1 distributing head signed topropel-the eilfinfthe-form' of unatomized droplets =inf aetrajectory locatedabove the vblast from the Vfan, against the inner face'of`-Wa1l 13,' with sufficient velocity toshatter'or atomize them. Securedto -the Lupperfend'of shaft 89;' 'by' means ofafset screw '93,`fis -a-l1ub member 94; to which is Welded-'a disc shaped fan lcover '-Dlate'.v

Securedtothe-underside of cover 95 area plu--v ralityz-of iflanged blades-t6? and 9131 whichare preferablyequally spaced. Blades y96 are prefer: i

Further; in ',a f; small-combustion :chambers-and hearth assembly as employed in the present Vcon--i` struction,..a high .air velocity tends to. zinducerexcessive :recirculation The :novel afan :assembly justadescribedaovercomesi this .diiiicu-lty :because r the greater number of short pumping rbladesY fas-.-v suresV sufficient volume ofvair forfcombu-stion without excess velocity;l yand ibylocating the; distributor` tubes -leeward' of. the. velocity blades 1 thetubes a are maintained-.rout of .contact fwith .thesheatedi recirculated gases that are inevitably 'drawnfinto' To further insure against'iexcessive recircula-'r tion by the tips of the oil tubes 92,' and to also protect the-tubes against excessive heating, cover 95 is provided with a short lip or skirt 96, and the ends of the inger tubes are llocated closely adjacent the fan cover.,V Both of these features cooperate to prevent the recirculatedy gases from heating andcarbonizingfthe oil in the ends of the distributor tubes.

vThe illustrated construction is a commercial unit ymarketed by the assigne'eof'this application and which-has given complete satisfaction `in all respects. The important dimensions of this vunit are as follows, which are given by way vof illustration and not limitation, it'b'eing understood that some latitude is permissible, Vdepending upon the size of the hearth, the speed of the fan and other factors of the particular unit under consideration.

lThe hearth is approximately inches in diameter and shield 'lr6 is spaced approximately 2 inches from the combustion chamber wall. Flame rim wall 'I3 is approximately 8 inches in diameter and one and one-half inches high, while shield 16 is three inches high. Grilles 86 are approximately one and one-half inches wide and one-fourth of an inch deep.

The fan is rotated at approximately 1600 R. P. M. The two sets of blades are of the same width and their inner ends all terminate approximately live-eighths of an inch from the axis of rotation. Blades 9i are approximately one and seven-eighths inches long, while blades 9S are approximately three-fourths of an inch in length.

My oil and air distributor supplies adequate air for combustion and yet is designed to effect a minimum recirculation of the combustion gases, particularly when used with a grille assembly that insures adequate combustion behind the flame rim, and it is possible to use a hearth and combustion chamber assembly of much smaller diameter than has heretofore been regarded as practicable in a wall flame burner.

'Ihe invention may be embodied in other specic forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a, liquid fuel burning apparatus, a rotary oil and air distributor unit comprising a head having a plate terminating at its periphery in a short downwardly directed skirt, a plurality of outwardly extending fan blades on the underside of said plate but terminating short of said skirt, a plurality of longer fan blades projecting outwardly beyond said skirt, and a plurality of oil delivery tubes extending upwardly and outwardly and terminating between said blades slightly inwardly of said skirt and just below the level of the lower edge thereof, said tubes having their outer ends located adjacent and leewardly of the longer blades during rotation of said head.

2. In a liquid fuelburner, a substantially vertical motor driven shaft, a' fuel distributor head mounted on said shaft," a plurality of= upwardly.- and outwardlyzextending fueldischarge'ytubes on said head having their upper ends turnedfsharply outwardly to discharge the fuel laterally, afan on said shaft comprising a hub securedto said shaft'and a cover extendingover .said tubes, Iandv a'plurality of spacedfan blades secured to theunderside of said cover andextending outwardlywith respect to said hub, a minor numberof said blades being long and projecting past the periphery of said cover and the remainder of saidbladeS.- which are disposed between said long blades tenminating short of the periphery of said coverwith.` both sets of blades being unobstructed vat their router ends so as to provide free lateral discharge;

of air from said fan, `and said upper ends of said tubes projecting between one of saidflong bladesand vthe short blade which is leewardv of said longy blade during rotation of said head with thelat-4 erally open upper ends of said tubes terminating;

short of the peripheiyofsaidcover. v

3'. In a liquid fuel burning apparatus,r a rotary;

blades being substantially uninterrupted at theirL outer ends so as to permit free discharge of air therefrom outwardly of said head, and said blades all combining to provide a large volume of air flow without excessive velocity outwardly of said burner head.

4. In a liquid fuel burner, a substantially vertical motor driven shaft, a fuel distributor head mounted on said shaft, a plurality of upwardly and outwardly extending fuel discharge tubes on said head having their upper ends turned sharply outwardly to discharge the fuel laterally, a fan on said shaft comprising a hub secured to said shaft and a cover extending over said tubes, a plurality of spaced fan blades secured to the underside of said cover and extending outwardlyl with respect to said hub, a minor number of said blades being long and projecting past the periphery of said cover and the remainder of said blades which are disposed between said long blades terminating short of the periphery of said cover with both sets of blades being unobstructed at their outer ends so as to provide free lateral discharge of air from said fan, and said upper ends of said tubes projecting between one of said long blades and the short blade which is leeward of said long blade during rotation of said head with the laterally open upper ends of said tubes terminating short of the periphery of said cover, and a short depending skirt in the periphery of said cover with the bottom of said skirt terminating above the upper ends of said tubes.

5. In a liquid lfuel burner, a substantially vertical motor driven shaft, a fuel distributor head mounted on said shaft, a, plurality of upwardly and outwardly extending fuel discharge tubes on said head having their upper ends turned sharply outwardly to discharge the fuel laterally, a fan on said shaft comprising a hub secured to said shaft and a cover extending over said tubes, and a plurality of spaced fan blades secured to the unu 77 def's1de== otisaid -.ooirer -and .extending-outwardly withc'respeot to said hub, a` minor numbery of said V'nlaldes'fbeing long :and projecting .past the 'periphery of saidicover and the remainder of said blades whichiare disposed lbetween said longzblades ter mi'rating 'short of the tperiphery of :said :cover with` both' sets ofv Vblades being unobstructed at their outer ends solas. to provide free lateral dis-4 charge' of-airfrom' said fan,v and said uppera ends oI-vsaid tubes projectingbetween-one of said-long.

blades'ffandrthe short blade which isleeward of said .long bl'ade duringmotation'of said head-With the laterally. open upper Sends of saidl tubesv .ter-

minating short of :the peripheryof said-cover,l

the buter .endsrof said discharge tubes terminatingoutwardly 'of fthe outerl ends of said short bladespf.

6. Inra-liquid fuelburning apparatus, arotar'y..

fuel and air. distributing unit comprising `fuel projectingmeans and airprojectingfmeans,.said air projecting means comprising a plurality of comparatively short pumping blades and an appreciably smaller numberof spaced longer air velocity,

bladeswith-bothfsets of blades being substantially uninterruptedatfther :outer: Vendsso as tto l eectf free-discharge of 'air .therefrom laterally of :said: g unit and said blades `:combining ita-provide 'alargevolume of. air flow Without excessive velocity ,out-

f. wardly of said'unit, and said fuel Iprojeotingmezainshaving outlets for dischargingifuel laterally. ofv

said unit located leewardly of said-longernblades during-normal rotational operation of said unit.

NOEhl-I. SUTTERFIELD.

REFERENCES4 CITED f The following frefe'rences l.are of vrecord inl the file 'ofthis patent:

UNITED STATESlllTEI'I'S

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