US2363099A - Burner for fuels containing tetraethyl lead and other objectionable foreign matter - Google Patents

Description

NOV. 21, 1944. 5 w u us 2,363,099

BURNER FOR FUELS CONTAINING TETRAETHYL LEAD AND OTHER OBJECTIONABLE FOREIGN MATTER Filed Aug. 3, 1942 2 Sheets-Sheet 1 80 '73) v 7 I, I 2? 1| |HHIHIH|||||E m 9 66 a2 77 l 1 m2 3 a I 75 I. 1 1 H 2/ ll/ 7/ .58 7 a 5% 7074 30 51 46 a 44 2 55 z,- l 43 68 r 9 as m /7 A;

INVENTOR 5 d W Tums.

ATTORNEY Nov. 21, 1944. B, w. TULLIS 2,363,099

BURNER'FOR FUELS CONTAINING TETRAETHYL LEAD AND OTHER OBJECTIONABLE FOREIGN MATTER Filed Aug. 3, 1942 2 Sheets-Sheet 2 INVENTOR E a- W Tul/f.

AT/TORNEY Patented Nov; 21, 1944 BURNER FOR FUELS CONTAINING TETRA- ETHYL LEAD AND OTHER OBJECTION- ABLE FOREIGN MATTER noyo w. Tullls, Wichita, Kans., assign'or to The Coleman Lamp andstove Company, Wichita,

Rana, a corporation of Kansas Application August 3, 1942, Serial No. 453,378

13 Claims.

This invention relates to liquid fuel burners particularly of the type disclosed in my application for patent Serial No. 426,420, filed January 12, 1942, and entitled Bumer for fuels contain- I ing tetraethyl lead.

As disclosed in the aforementioned application, fuels containing gums, coloring matter, and. antiknock compounds such as tetraethyl lead do not function satisfactorily in the gas generating type of burners for the reason that the foreign particles decompose or. carbonize in the nozzle' and generating zone of the burner. Consequently the generators and nozzle tips are clogged within a very few hours burning time. In small burners of the type disclosed in my previous application, for example those having an output of approximately 5,000 B. t. u. or less, these difficulties are overcome by conducting a predetermined-amount of heat to the vaporizer tube for vaporizing only the low boiling fractions of the fuel within the tube so that the tetraethyl lead and the higher boiling fractions containing the gums, coloring matter and other foreign particles rare discharged therefrom in liquid or-atomized state, the principle being that the vaporized low boiling fractions maintain combustion of the undesirable particles exteriorly of the vaporizing tube. However, when large burners are considered, for example those having 10,000 B. t. u. heat output, ,Lfind that means is required to reduce the temperature of the vaporizer dis charge tip. Otherwise heat of combustion is radiated thereto, which, supplemented by the heat conducted from the adjacent portion of the""vapo1'izer tube, causes too-high temperatures in the portions of the vaporizing zone most likely to become clogged. v

The purpose of the present inventiii is, therefore, to provide means for getting su cient heat to the vaporizer to vaporize an adequate amount of the low boiling fractions of the fuel and to :point at which combustion is effected relative to the discharge tip of the vaporizer; and to pro- -vide for aspiration of cooling air around the discharge tip of the nozzle in sumcient quantity to maintain desired temperature but in insuflicient quantity'to support combustion below the desired level above said tip. I

In accomplishing these and other objects of the invention, I have provided improved details of structure, the preferred form of which is illustrated in the-accompanying drawings, wherein:

Fig. l is a verticahsection through a liquid fuel burning appliance equipped with a burner embodying the features of the present invention,

the fuel tank of the appliance being shown in part elevation.

Fig, 2 is a detail perspective view of the A vaporizer and burner unit removed from the appliance, a part of the draft shield being broken away to better illustrate the air inlet openings in the discharge nozzle of the vaporizer:

Fig. 3 is a' plan view of the burner.

Fig. 4 is a plan view of the burner bowl with the flame deflector removed to show the tabs for controlling air flow and the level of combustion relative to the nozzle tip.

Fig. 5 is a cross-sectiononthe line 5-5 of Fig. 1.

Fig. 6 is a cross-section on the line 6-5 of Fig. 1.

Fig. '7 is a perspective view of a burner equipped with a modified form of tabs.

Referring more in detail to the drawings:

1 designates a fuel burning appliance, for example a portable stove, equipped with a burner embodying the features of the present invention. While I have particularly illustrated a stove, it is to be understood that the invention is applicable to any heating or cooking appliance which is to'be operated with a liquid type fuel. The stove illustrated in conjunction with my improved burner is for general utility purposes, characterized by its ease of transportation, and is, therefore, one to which the present burner is especially adapted because of inability to obtain fuels free of anti-knock compounds in many localities in which such a stove is used..

The specific structure of the stove forms no part of the present invention but is illustrated to better disclose my invention,- and is briefly described as including a tank or fount 2 for containing fuel to be supplied to the burner 3 OFFICE port l2 of the valve [0.

mitted to the tank through a filler neck 4 ordinarily closed by a pressure-tight cap 5.

Mounted within the tank is a pump 9 having a plungerlnot shown) adapted to be reciprocatedby a-rodfl extending through a packing unit in the wall of the tank and actuated by a knob 3 so as to provide sumcient pressure in the top of the tank for displacing the fuel by way of a conductingpipe 9 through a valve In to the generator or vaporizer tube H of the burner, later described. The pipe 9 is connected with the inlet The valve includes a body l3' having a threaded portion l4 engaged withinv the opening of a bushing I5. Projecting from the valve body is a lateral arm l6 provided with an internal axial bore l1 extending transversely of the port 12 and having a valve seat I8 therein which connects the'port I2 with an upper bore l9 through an off-set connecting port 20. R-

T -tatable within the bore of the arm I6 is a valve stem 2| having'threaded connection asat 22 witha portion of the bore to efiect movement of a conical valve 23 thereon'to and from valving relation with the seat l8. The opposite end of the stem extends through a suitable packing assembly 24 and carries an operating knob 25. Reciprocable within the port [2' and bearing against the conical portion 23 of the valve stem is atomization of the fuel upon starting of thea fuel throttling rod 25 for effecting initial burner, as later described.

Carried within the upper bore I9 is the head 21 of a clean-out needle 28 that extends axially through the generator or vaporizer tube H and operates through the jet opening 29 of a nozzle 30, later described. The head 21 has a laterally opening recess 3! therein receiving an eccentric pin 32 on the end of a shaft 33 that is rotatablymounted within a nipple 34 threaded in a boss 35 projecting laterally from the body of the valve. The shaft 33 also extends through a packing assembly 36 and is operated bya handle 31.

Formed '.0n the upper end of the valve body is a threaded neck '38 havinga bevelled annular seat 39 seating a flaring flange 40 of the va-" porizer tube H, the flange being retained in seated position by a union nut 4| threaded upon the neck 38. An upper portion near the end of the tube I l is threaded, as.at.42, and projecting thereabove is a section '43 to limit conduction of heat upward to the nozzle 30. The section 43 is .of reduced diameter'and has an internally threaded axial bore 44 for mounting the nozzle 30, previously mentioned. The nozzle. includes a threaded skirt -45 turned into the threaded bore ofthe collar 43 and cooperating with an' annular shoulder 46 to fox-ma liquid-tight seal. Projecting above the shoulder 46 is an annular guard lip 41 encircling thejet opening 'or-orifice 29. The inner diameter of thetube- H: is'sub-" stantially greater than the diameter of the bores I 48 of thenozzle.

In order to'promote, contact of the fuel with heat conductive surfaces, the tube llcontains a roll of screen material 49 retained in roll form by a wire wrapping 50 as shown in Figs. 1 and 6.

The burner proper includes a bowl" 5! having a substantially hemispherical portion 52 carried by an axial collar 53 that is fixed thereto by a" flange-54 positioned in an opening 55 in the .bottom ofthe bowl and having the upper edge spun against the inner face of the. bowl..- The collar 53 has an inner diameter conforming tothe' outer diameter of the tube II and 11845 tht.

lower portion thereof internally threaded to engage the external threads 42 on the upper portion of the tube H. The, reduced section 42 of the vaporizer tube, being of smaller diameter. cooperates with the collar 53 to form an annular air passageway 56 surrounding the discharge end of the vaporizer tube and the nozzle, which are located above the connection of the burner bowl with the tube H. The threaded connection of the burner bowl with the tube provides a path for conduction of, heat from the burner bowl to -the vaporizer to supply suflicient heat for vaporizing the low boiling fractions of the fuel. The extent of the connection is only sufficient to conduct, the amount of heat necessary to effect vaporization of the lower boiling fractions without vaporizing the higher boiling fractions and decomposing I the undesirable components.

The collar 53 has an annular series of air inlet ports 51 through which air is drawn by the aspirating effect of the fuel discharged through theorifice 29. The upper part ofthe hemispherical portion fo the bowl has a laterally extending annular shoulder 58 which terminates in an upwardly and outwardly flaring rim 59. Formed in'the' sidesof the hemispherical portion are a plurality of air inlet openingsill formed by slitting the metal and pressing tongues or tabs 6| inwardly therefrom so that they converge upward-ly. The tonguesyhave substantially a 90 twist therein as indicated at 62 so the ends are positioned substantially radially with respect to the'axis of the nozzle tip and are so arranged as to form substantially an opening 62 inspaced alignment with the nozzle 30 as best illustrated in Figs. 1 and 4. When thus formed the tongues are spaced apart at the side edges as indicated at 63 to permit entrance of air into the stream of fuel discharged from the nozzle. of the generator. The openings 53 are relatively small so that the air supplied therethrough is insuflicient to support combustion below the 'upper. ends of the tongues.

kept at an elevation in spaced relation with the discharge of the nozzle so that the radiant heat of the flame will have less eflect thereon; The

major portion of the air to theburner is taken through the openings which directly connect with the space above the tonguesand which provide suflicient air to support combustion of the fuel.

The twists .62 in the tonguesgive a directional movement to the air drawn through the openings 60 so that they create turbulence and better mixture of the air with the fuel and serve to bring the flame into. contact with the burner.

bowl which causes additional heat to be conducted to the generator.

Carriedupon the rim of the burner bowl is a deflector plate 64 against which the flame impinges and by which the flame is directedoutwardl-y to lap the inner face of-theffiaring rim T 59. The deflector 64 includes a substantially flat plate having the side edges 65 spaced from the flected flame plays against the bottom of a vessel: or the like supported by a grid, later described. The flame spreadingacross the burner bowl rim to provide openings through which the deeffects draft of combustion supporting air into the bu'stion of the fuel. v The flame deflector is supported in position by means ofradially extendingarms 56 projecting 'Consequently the flame of the burning fuel will be burner through the openings fill to support com-' from the corners thereof. and .having hook-like pprtions 61 engaging over the rim of the burner bowl as. shown in- Fig. 2. In order to control the amount of combustion supporting air and prevent drafts from interfering with operation of the flame, the burner is encircled by a sleeve 68 spaced from the periphery of the burner bowl to provide an annular passageway 69 for flow of secondary air. The shield is supported in position by means of depending extensions on the ends of the hook-like portions 61 of the arms 66. The shield extends downwardly over the vaporizer tube so that air moving into the burner passes in close relation thereto to cooperate with the heat conductive capacities of the burner bowl in maintaining the predetermined practically constant uniform temperature of the tube walls.

The shield and the deflector plate are retained in position on the burner bowl by screws H threaded in openings 12 of the shield and registering openings I3 in the depending ends of the arms so that the shanks 14 of the screws engage under the annular shoulder 58 as illustrated in Fig. 1.

The grid previously mentioned includes a ring 15 supported from the fuel supply tank by rodlike posts 16. Formed in an inwardly extending annular flange ll of the ring 15 is a plurality of upwardly formed elongated bosses 18 having slots I9 in;the top thereof to mount grid fingers 80 thereon, the grid fingers having ear. portions 8| depending from the lower side to accommodate pivot pins 82 that extend through the sides of the bosses and through the ears as shown in Fi In operating the burner constructed and. assembled as described, a fuel, for example an ordinary automotive gasoline, ispoured into the tank through the filler neck 4 leaving an air spac between the surface of the fuel and the in the tank moves therewith to effect atomiza-- tion of the fuel, the mixture being discharged upwardly through the valve body and vaporizer tube at sufficiently high velocity and pressure to be discharged from the nozzle in a fine mist which is readily ignited to start the burner. The resultant flame plays against the deflector 64 and is directed outwardly against the inner surface of the rim 59 to heat the metal' thereof and cause an updraft of air from the lower end of the sleeve 68 through the openings 60 into the burner bowl, and through the passageway 69 formed between the deflector plate and the rim 59. The heat is conducted downwardly through the hemispherical portion of the bowl to the collar 53 thereof and through the threaded connection to the wall of the vaporizer or vaporizer tub H, the rate of 'heat conduction being controlled by the extent of engagement of the threads, the thickness of the metal of the burner bowl, and the volume ofair contacting the parts. The heat thus conthe gas begins to discharge into the burner bowl the fuel control valve I0 is opened suflficiently wide to allow movement of the'stem of the throttling rod 26 upwardly along the conical end 23 of the valve stem 2| so that the lower end of the throttling rod 25 limits the inlet of the pipe 9 and only liquid fuel flows under pressure to the generating chamber. I find that ordinary leaded motor or automotive fuels may be preheated in thejgenerator to approximately 4Q0- F. to. 450F. without appreciable vaporizatioifo'f the heavier fractions which contain the objec ,tionable gums. tetraethyl lead. and the like.

While the lead content may become volatile at these comparatively low temperatures it does not begin to separate "and form solid deposits until the temperature rises to a higher degree. Therefore, since the burner structure is designed to maintain a fuel temperature within the vaporizer of approximately between 400 F. and 450 F. it is not sufficiently hot to effect vaporization of the higher boiling point fractions of the fuel or break down of the tetraethyl lead compound.

Discharge of the fuel through the orifice 25 produces an aspirating effect toedraw air through the ports 51 into cooling contact with the nozzle 30. The amount of air drawn therethrough supplemented by the air'drawn through the openings 60 is not sufficient to support combustion below the upper ends of the tongues 61 so that the flame is spaced sufficiently from the nozzle tip to avoid overheating thereof. The tongues also act in effecting turbulence to assure bet-- ter mixture with the vaporized fuel and promote dissipation of theobj'ectionable components of the fuel. Should any. objectionable matter be deposited it is so light. and infinitesimal that the orifice of the nozzle is readily cleared there'- of by the cleaning needle. Therefore the burner will operate over a long period of time without repair or replacement of the vaporizer tube and nozzle even though automotive fuels are used in the stove.

In Fig. 7 is shown a burner equipped with a modified form of tongues GI. In this form the tongues are not twisted and the ends 6i" form a substantially rectangular opening 62 through which the fuel mixture is discharged.

If it is desired to enrich the mixture of air and fuel the tabs may be bent up in closer relation with the air inlet openings of the burner bowl or if it is desired to make the mixture less rich the tongues may be bent down or further from the openings.

What .I claim and desire to secure by Letters Patent is:

1. In a liquid fuel burner, a fuel vaporizer tube having a threaded exterior spaced from the discharge end of said tube, a nozzle mounted. in the vaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air, a collar on the burner bowl enporting combustion between the tongues and said nozzle.

2. In a fuel burner for burning liquid hydrocarbon fuels, a fuel vaporizer tube. having a threaded exterior intermediate the ends of said.

tube, a nozzle connected with the vaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air, and a collar on the burner bowl engaging said threads of the vaporizer and provided with air inlet openings for admitting air around the nozzle.

3. In a fuel burner for burning liquid hydro-' carbon fuels, a fuel vaporizer tube having a threaded portion intermediate the ends of said tube, a nozzle mounted in the vaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air,'a

, collar on the burner bowl engaging said threads of the vaporizer and provided withair inlet openyings for admitting air around the nozzle, and

tongues carried by the burner bowl and converging upwardly and inwardly above the nozzle to limit flow of air immediately surrounding the nozzle to an amount insuflicient for supporting combustion between the nozzle and said tongues.

4. In a fuel burner for burning liquid hydrocarbon fuels, a fuel vaporizer tube having a threaded exterior portion intermediate the ends of said tube, a nozzle mounted in the vaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air, a collar on the burner bowl engaging said threads of the vaporizer and provided with air inlet openlugs for admitting air around the nozzle, tongues carried by the burner bowl and converging upwardly and inwardly above the nozzle to limit flow of air immediately surrounding the nozzle to an amount insufficient for supporting combustion between the tongues and said nozzle, a flame deflector over said tongues, and means supporting the deflector in heat conductive relation with the burner bowl for supplying vaporizing heat to the vaporizer through said threaded connection.

5. In a fuel burner for burning liquid hydrocarbon fuels, a fuel vaporizer tube having a threaded exterior portion intermediate the ends of said tube, a nozzle mounted in the vaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air, a collar on the burner bowl engaging said threads of the vaporizer, and tongues carried by the burner bowl and converging upwardly and inwardly above the nozzle, said tongues being adjustable relative to said inlet openings of the burner bowl.

6. In a fuel burner for burning liquid hydrocarbon fuels, a fuel vaporizer tube having a threaded exterior portion intermediate the ends of said tube, a nozzle mounted in thevaporizer tube above said threads, a burner bowl having air inlet openings for combustion supporting air, a collar on the burner bowl engaging said threads of the vaporizer and provided with air inlet openings for admitting air around the nozzle, and tongues carried by the burner bowl and converging upwardly and inwardly above the nozzleto limit flow of air immediately surrounding the nozzle to an amount insufficient for supporting combustion between the tongues and said nozzle, said tongues being adjustable relative to said inlet openings of the burner bowl.

'I. In a fuel burner for burning liquid hydrocarbon fuels, 9, fuel vaporizer tube, a nozzle mounted in the vaporizer tube, a burner bowl having heat conductive connection with the va porizer tube and provided with air inlet open ings for combustion supporting air, and tongues carried by the burner bowl and having a shape to effect turbulence of the air admitted through said openings, said tongues being arranged about the fuel stream discharged from the nozzle to limit flow of air immediately surrounding the nozzle to an amount insuflicient for supporting combustion between the discharge tip and terjminal ends'aof said tongues.

8. In a fuel burner for burning liquid hydrocarbon fuels, a fuel vaporizer tube, a nozzle mounted in the vaporizer tube, a burner bowl having air inlet openings for combustion supporting air, a collar on the burner bowl in heat conducting contact with the vaporizer tube and provided with air inlet openings for admitting air around the nozzle, and tongues carried by the burner bowl and having twists therein to efl'ect turbulence and converging upwardly and inwardly above the nozzle to limit flow of air immediately surrounding the nozzle to an amount insuflicient for supporting combustion between the tongues and said nozzle.

9. In an apparatus for burning a liquid hydrocarbon fuel composed of fractions having different boiling points, a burner bowl having an air inlet opening for admitting combustion supporting air into. the burner bowl, a: vaporizer having an end discharging into the burner, means for supplying fuel to the vaporizer, a heat conductive connection between the burner bowl and air into cooling contact with said discharge end of the vaporizer, and flame control means in the burner bowl and. spaced fromthe discharge end of the vaporizer for limiting flow of said cooling air to an amount insufllcient for supporting combustion in said space when the apparatus'isin operation.

10. In an apparatus for burning a liquid hydrocarbon fuel composed of fractions having different boiling points, a fuel vaporizer, a burner bowl above the vaporizer having an air inlet for admitting combustion supporting air, means for supplying fuel to the vaporizer, a heat conductive connection between the burner. bowl and the vaporizer for conducting an amount of heat required to effect vaporization of a selected fraction of the fuel, a nozzle tip on the vaporizer for discharging the fuel into the burner bowl, a

zle, and flame control means between the flame deflector and nozzle for retaining the flame in said burner bowl inspaced relation with the ,nozzle to limit the effect of radiated heat on the nozzle when the apparatus is in operation.

11. In an apparatus for burning liquid hydrocarbon fuel composed of fractions having different boiling points, a fuel vaporizer, a burner bowl above the vaporizer having an air inlet opening for admitting combustion supporting air to the burner, a flame deflector supported in the burner bowl above said opening for deflecting flame into contact with the burner bowl, means for supplying fuel to the vaporizer, a heat conductive connection between the burner bowl and vaporizer to conduct heat for effecting vaporization of selected fractions of the fuel within the vaporizer, a nozzle on the vaporizer for discharging the fuel into the burner, said heat conductive connection having an opening posi-, tioned relative to the nozzle for passing air to disperse heat radiated from the flame deflector in the direction of said nozzle, and means in the burner between said openings for retaining the flame of combustion in spaced relation with the nozzle when the apparatus is in operation.

12. In an apparatus for burning liquid hydro carbon fuel composed of fractions having different boiling points, a fuel vaporizer tube having a threaded exterior portion intermediate the ends of said tube, a burner bowl above the vaporizer having air inlet openings for admitting combustion air into the burner bowl, means for supplying fuel to the vaporizer, a collar on the burner bowl to receive heat from the-burner bowl and having a, threaded portion engaging said threads of the vaporizer for conducting an amount of heat required to effect vaporization of a selected fraction of the fuel, a nozzle tip in the vaporizer above said threads for discharging the fuel into the burner bowl,

said collar having air inlet openings for admitting air around the nozzle, and means within amount of heat required to effect vaporizationthe burner bowl and spaced'from said nozzle for retaining the flame of combustion in said burner in-spaced relation with the nozzle to limit the effects of radiated heat on the nozzle when the apparatus is in operation.

13. In an apparatus for burning liquid hydrocarbon fuel composed of fractions having different boiling points, a fuel vaporizer tube havin a threaded exterior portion intermediate the ends of said tube, a burner bowl above the vaporizer having air inlet openings for admitting combustion air into the burner bowl, means for supplying fuel to the vaporizer, a collar on the burner bowl to receive heatfrom the burner bowl and having a threaded portion engaging said threads of the vaporizer forconducting an of a selected fraction of the fuel, a nozzle tip in the vaporizer above said threads for discharging thefuel into the burner bowl, said collar having air inlet openings for admitting air around the nozzle, means within the burner bowl and spaced from said nozzle for: retaining the flame of combustion in said burner in spaced relation with the nozzle to limit the effects of radiated heat on the nozzle when the apparatus s in operation, and a flame deflector supported within the burner bowl above the combustion air inlet openings for deflecting the flame into heating contact with the burner bowl.

BOYD w. TULLIS.

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