US2568878A

US2568878A - Oil burner nozzle

Info

Publication number: US2568878A
Application number: US14731A
Authority: US
Inventors: Sr Hubert J Wiser
Original assignee: EUREKA WILLIAMS CORP
Current assignee: EUREKA WILLIAMS Corp
Priority date: 1948-03-13
Filing date: 1948-03-13
Publication date: 1951-09-25
Anticipated expiration: 1968-09-25

Description

Sept. 25, 1951 H. J. WISER, SR

OIL BURNER NOZZLE Filed March 13, 1948 INVENTOR. HUBERT J. WISER SR.

BY 47 8 4s ATTORNEV Patented Sept. 25, 1951 OIL BURNER NOZZLE Hubert J. Wiser, Sr., Bloomington, Ill., assignor to Eureka Williams Corporation, Bloomington, 111., a corporation of Michigan Application March 13, 1948, Serial No. 14,731

4 Claims. (01. 299120) 1 This invention relates to oil burner nozzles of a, kind which is particularly applicable for forming a primary mixture of fuel and air to be discharged from the nozzle into a secondary air nozzle or passage beyond which the combustible mixture so formed is burned in an oil burner combustion chamber.

An object of the invention is to provide an improved nozzle of this type in which a better atomized and more thoroughly mixed primary mixture can be formed.

Other and further objects of the invention will be apparent by reference to the accompanying drawings of which there is one sheet, which, by way of illustration, shows a preferred embodiment and the principles thereof and what I now consider to be the best mode in which I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims. I also contemplate that of the several different features of my invention, certain ones thereof maybe advantageously employed in some applications separate and apart from the remainder of the features.

In the drawing:

Fig. 1 is a fragmentary cross sectional view of an oil burning furnace showing a nozzle embracing the principles of the invention and being illustrated in operative position relative to the secondary air passage or nozzle of the burner and the oil burner combustion chamber;

, Fig. 2 is an enlarged fragmentary longitudinal sectional view through the nozzle illustrated by structure disclosed by Fig. 2, except that Fig. 5

is taken substantially on the plane of line 55 on Fig. 2 and illustrates the front end of the inner tubular body member of the nozzle in elevation. I

Referring particularly to Fig. 1, numeral Ill indicates generally an oil burning furnace hav- 4 ing a combustion chamber II surrounded by a .wall I2.

The wall I2 is provided with an opening indicated at I3 in which is secured an air cone or nozzle member I4 through an orifice I6;

in which secondary air is discharged in a blast into the combustion chamber II. The member I I also is provided with a plurality of circular openings I'I surrounding the opening I6 through which additional quantities of secondary air also are discharged into the combustion chamber II around the periphery of the blast of secondary air introduced through the nozzle opening I6.

Disposed concentrically with and just inside of the secondary air orifice or nozzle I6 is a primary fuel and air mixing nozzle indicated generally at I8. The nozzle It comprises an outer tubular member body I9 containing an inner tubular member or body 2I, the two tubular bodies being adapted to be assembled as a unit and secured by a nut 22 to an air supply conduit 23 projecting from the casing 24 of an oil burner fuel and air pumping or supply mechanism, only partially shown. The fuel and air supply mechanism may be of any suitable type wherein pumping mechanism is provided for supplying liquid fuel and air to the nozzle I8 at relatively low and substantially equal pressures and wherein fan or other suitable means i 'provided for supplying secondary air to the secondary air nozzle I I which is located about the primary fuel and air mixture nozzle I8. For a more complete description of an oil burner system of this type and the primary and secondary air, and the fuel pumping, metering and fan mechanism employed therein, reference may be had to the copending applications for United States Letters Patent of Howard E. Earl, Serial No. 2,881, filed January 17, 1948, for Oil Burner System, now Patent No. 2,554,491; Howard E. Earl, Serial No. 772,970, filed September 9, 1947, for Motor Compressor Unit, now Patent No. 2,542,121; and Robert R. Witherell, Serial No; 13,718, filed March 8, 1948, for Oil Burner Pumping Unit.

The liquid fuel referred to is supplied to the nozzle I8 by a conduit 26 which is connected to the hollow interior of the inner tubular member 2I by a tube or conduit 21. A spring 28 disposed about the tube 21 and abutting the adjacent ends of the conduit 26 and the inner tubular member 2| holds the inner tubular member 2I within the outer tubular member I9 and in contact with the front end of the latter.

The primary air supply conduit 23 surrounds the fuel supply conduit 26 and the tube 21 and supplies primary air to the nozzle I8 through the annular space therebetween. Such air is supplied to the nozzle I8 through a plurality of air supply passages indicated at 29, these passages being formed between the outer and inner tubular bodies or members indicated at l9 and 2| respectively.

Referring particularly to Figs. 2 to 5, the outer body I9 is provided with a front wall 3| in which a knife-edge orifice indicated at 32 is concentrically formed. The orifice 32 forms the extremity of a frusto-conical surface indicated at 33 which provides the interior surface of the front wall 3 I.

The inner tubular member 2| is provided with a closed front end 34 from a central portion of which projects a conical tip 36 which extends toward the orifice 32 in concentric relation thereto. The front end 34 comprisesralplanular surface indicated at 31 which:extends'normallywith respect to the axis of the inner tubular member 2| about the base of the tip-36-and-which is in turn surrounded by an annular tapering seat indicated at 38, which is adapted to engage-and to closely fit the innentapering surface 33 of the front wall: 3| :of: \the body IS.

(The: annular seat 38iwherr engaging the front zwall'3l in the manner described divides the front :-endof thenozzle |8:into:a;tip chambers39 and an annular-mixing chamber :4! which is formed 6: about. the front end of the inner tubular member I21 anteriorrelation to the seats-38. :Theannular mixing-chamber 4|: is' formed :between an outer cylindrical lsurfacezutformed at'the front of the inner'tubular member 2| and the inner:

cylindricalsurfacet43 OIlthG outer tubular member=|9.' The remaindenofithe exterior surface of theinnertubuiar memberi'zi isiformed by a plurality' of planular surfaces indicated at 44 which :extend as planular chords across the inner cylin-w drical surfaceof the outer member l9 and-be- --tween' the ends of-which-are'formed arcuate longitudinally extending seats indicated at "'46.

Seats 48 divide the spacebetweenthe exterior inner tubular member-2|. Between the passage 41 and the annular mixing chamber 4| are a plurality of fuel supply ports or passages indicated at48-, and by which latter ports or passages fuel is supplied from the passage 41' to the annular chamber. The passages 48 are equallyspaced with respect to one another and are onset with respect to the axis of the inner tubular member 2| in such manner as to have a tangential relation to the annular chamber 4| at the ends of thepassages 48' which communicate with the annular chamber 4|. Theouter ends of the passages 48 communicate with the annular chamber 4| approximately midway between the front and rearends of the annular chamber 4| and are formed in such a way as to provide relatively sharp knifeedgesover which fuel from the interior of themember 2| is suppliedto-the annular-chamber 4|. The *ends of the passages48 communicate with the annular chamber 4| approximately midway between the central por- -tions ofthe'ends'ofthe air supply passages 29 -which also communicate with the annular -chamber 4| .Formed across the annular seat 38 between the annular-chamber 4|and the tip chamber 39* are angle with respect to the annular chamber 4| and therefore have a similar tangential relation to annular seat 38.

the annular chamber 4 The ends 53 communicate with the: annular chamber 4| between the ends ofthepassages 48 and somewhat nearer the The; cross sectional contour of the passages 49 is considerably less than the cross sectional contour of the annular chamber 4|, of the passages 29, and of the chamber 39. Under such circumstancesiiair.whichfsmay be supplied by the spassages 29 :will fiowzinto' the annular chamber -4| and thence willflow in a plurality ofspiral'paths,

through the passages 49 and into the tip chamber 39. The passagesu49beingmuch smaller than the other passages andchambers referred to, it will be apparent that the velocity of.'the=air in the passage's 49 a will i be considerably greater than the. velocity of the air in the other passages referred to. Also, due'to'the slope or spiral relation of the passages 49 to'the annular chamber discharged into the chamber 39. since'the' fluid in all of such passages will rotate in the direc'tion offering the least resistance, it will be apparent thatthe air and liquid fueladmitted' to thean- --nular"chamber" 4| fromthe air and fuel supply passages 29 and, respectively, will rotate'in the annular chamber 4| in a clockwise directiom es the nozzleappears inFigs. 4- and 5. For the same -reason,- it will be apparent that the fluid discharged -by the passages- 49 into the tip chamber "39 also Willrotate in a clockwise direction in the tip 'ohamber' 39,as the'nozzle appears in Fig; 5.

It will be apparent'from Fig. 4that the'passages 48 are somewhat inclined toward or facing the direction of rotation of "fluid in the annular chamber-4| which will cause the passages to provideparticularly sharp'knife edges over which the liquid fuel'from the passages 48 is supplied to the annular chamber'l l.

Dueto the relation of the ends of the

passages

29', 48, and 49 whichcommunicate with the annular-mixing chamber4 it will be apparen't'tliat air which is supplied to the annular chamber through anyone-of the passages 29 will tend to flow across the outer end of an adjacent passage 48 beforereaching'the end of 'the passage 49 the front of the nozzle I8, it'will be apparent that "the fuel in such mixture will be required to pass over a plurality of sharp edges before being discharged as such primary mixture. These edges include the edges formed at the outer extremities of the passages 48, the edges at the opposite ends of the'passages'fl, and the knife edge of the-oriiice 32. Such sharp-or knife edges tend to finely divide or atomize' the fuel and hence to thorough- 1y mix the fuel with the air as the fuel and air rotate in the mixing chamber H, as such-fuel and air passes through the passages-49, as such fuel and air rotate Within the tip chamber 39,-and

as such fuel and air is discharged through the burning primary mixture in the proper ratio to i complete the combustion of the fuel supplied by the nozzle.

While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification, and I 2 therefore do not wish to be limited to the precise details set forth, but desire to avail myself of 'such changes and alterations as fall within the purview of the following claims.

I claim:

1. An oil burner nozzle comprising an outer tubular body having a circular knife-edge orifice formed coaxially therewith at the front end thereof, an inner tubular body within said out'er'body and having a front end formed-to provide an annular seat disposed in engagement with said outer body and being spaced from said outer body on opposite sides of said seat to provide a tip chamber communicating with said orifice and an annular mixing chamber separated from said tip chamber by said seat, one of said bodies being formed to provide a plurality of passages across said seat between said mixing chamber and said tip chamber, the cross section of said passages being not greater than that of said annular chamber, said passages being formed in similarly sloped relation to one another and being symmetrically related to said mixing chamber and said tip chamber with the opposite ends of said passages opening into said mixing chamber and said tip chamber in directions tangently related to said chambers so as to induce a unidirectional rotation of fluid in said mixing chamber and in said tip chamber, air supply passageways communicating at their forward ends with said annular chamber and through which air supply passageways air under pressure is supplied to said annular chamber, a plurality of spaced oil supply ports communicating between the interior and exterior of said inner tubular body and in advance of the passage ends in said annular chamber and through which oil supply ports-oil is supplied for mixture with the air supplied through said air supply passageways, said oil supply ports discharging jets of oil into said air in advance of the passage ends in said annular chamber, said nozzle construction being such that oil is mixed with air and such mixture is rotated in said annular chamber and in flowing from said annular chamber into said passages such mixture breaks over the edges of said passages and changes directions, and such mixture further breaks over the edge of said orifice and changes direction in passing from said tip chamber through said orifice.

2. An oil burner nozzle according to claim 1 in which the front end of said inner tubular body is provided with a conical tip projecting toward said orifice and disposed concentrically with respect thereto, said passage ends projecting into '6 said tip chamber in a direction so. as to project a mixture of oil and air toward a wall of said tip chamber opposite said conical tip whereby said mixture will whirl around said tip chamber and break over the knife edge thereof.

' 3. An oil burner nozzle comprising an outer tubular body having a circular knife-edge orifice formed coaxially therewith at the front end there.- of, an inner tubular body within said outer body and having a front end formed to provide an annular seat disposed in engagement with said outer body and being spaced from said outer body Eon opposite sides of said seat to provide a tip chamber communicating with said orifice and'an annular mixing chamber separated from said tip chamber by saidse-at, said front end of said inner ,tubular'body having a conical tip projecting to.- ward said orifice and concentrically with respect thereto, .one of said bodies being formed to provide a plurality of passages across'said seat between said mixing chamber and said tip chamber, the cross section of said passages being materially less than that of said annular chamber,

said passages being formed in similarly sloped relation and being symmetrically related to said mixing chamber and said tip chamber with the opposite ends of said passages terminating within said mixing chamber and said tip chamber, .said passage ends opening into each of said cham- -bers in directions tangently related to said chambers so as-to induce a unidirectional rotation of fluid in said mixing chamber and said tip chamber, a plurality of spaced oil supply ports communicating between the interior of said inner tubular body and said annular chamber and through which oil supply ports oil is supplied to said annular chamber, said ports having a relation to said annular chamber forming relatively sharp edges across the line of flow of fluid in said annular chamber, said sharp edges being positioned between the opposite ends of said annular chamber and in advance of said passage ends in said annular chamber, said inner body on the side of said annular chamber remote from said, annular seat being formed to provide a plurality of seats engaging the interior of said outer body for dividing the space between said inner and outer bodiesinto a plurality of longitudinally disposed air supply passageways communicating at their forward ends with said annular chamber, and through which air supply passageways air under pressure is supplied to said annular chamber, said oil supply ports communicating with said annular chamber between said forward ends and said passage ends and discharging jets of oil into the air supplied through said air supply passageways, said nozzle construction being such that oil is mixed with air in said annular chamber and such mixture breaks over the edges of said passages and changes direction in flowing from said annular chamber into said passages and is projected toward a wall of said tip chamber, and such mixture further breaks over the edge of said orifice and changes direction in passin from said tip chamber through said orifice.

4. An oil burner nozzle comprising an outer tubular body having a circular knife-edge orifice formed coaxially therewith at the front end there of, an inner tubular body within said outer body and having a front end formed to provide an annular seat disposed in engagement with said outer body and being spaced from said outer body on opposite sides of said seat to provide a tip chamber communicating with said orifice and an annular mixing chamber separated from said tip annular "chamber; said oilsupply ports communiliiai'nber bysaid seatj said front 'en'd "tubular body having a-"conical" .tip Jprojectin'g.:to-

wird said orifice and concentricallywith respect thereto; one-o1 i said bodies bein'g'formed to provide a plurality -ot' passages across said seat'bet'weensaid mixing chamber and'said tip. chamber,

' the cross section of saidpassages being materially than that of-said annulanehambensaidpas- 'iages' 'being formed in similarly sloped' relation andbeing' symmetrically related to 'saidmixin ol'iamber' and saidl tip chamber with the opposite ends of said passages terminating inxequally mg between the'interior of said inner tubular body =lndsaid annular chamber and opening into'asaid annular :chamber "between the opposite ends of said I annular chamber and in advance of said passage endsinsaid annular chambensaidinner body on the side ot'said annular chamber remote Jfiom saidannular seat being formed to provide longitudinally disposed seats engaging'the interior 0!" said outer body for dividing the space between -saidfinner'and outer bodies into apluralityof Jongitudinally 1 disposed I air supply passageways Peomrnuhicating at their forward ends with: said eetingw-ithsaid annular chamber between said forward ends and saidpassage ends and dis- Charging Jetsof oil into the'air supplied through flidair supply-passageways, said nozzle construction being such that oil is mixed with air in said annular chamber andsuch mixture breaks over theedges of said passages and changesdirection in'i'iowingfrom saidannular chamber into said "pessages andsuch mixture further breaks over the edgeiof said orifice-and changes direction in ipassing from said tip chamber through said oriflee.

HUBERT J. WISER. Sn.

-REFERENCES CITED The following references are of record in the me of thisapatent:

UNITED STATES PATENTS "Number Name Date --1,227,-867 Young May 29, 1917 5153345755 Wil1ilatms. Nov. 14, 1933 2,055,864 Harsch s Sept. 29,-1936 2,249,482 Macchi July 15,4941 2,284,264 Crisp May 26, 1942 FOREIGN PATENTS Number Country Date 82,573 Sweden June 28, 1932