US2411342A - Hydrocarbon combustion tube burner - Google Patents

Description

Nov. 19, 1946. R. M. SHERMAN HYDROCARBON COMBUSTION TUBE BURNER 3 Sheet s-Sheet 1 Filed March 17, 1944 w w m r a Wm m a. a M I n a h 2 s h a a Z 9 7 h l d.\ 7 w m nwfi 9 1 W m 9 a a o\ W 7 O 0 \5 7 I k a 3 Sheets-Sheet 2 R. M. SHERMAN HYDROCARBON COMBUSTION TUBE BURNER Filed March 17, 1944 Nqv. 19, 1946.

' Ivenioz'. Rallgionlqsher uan i I eflfi'ys Nov. 19, 1946. R. M. SHERMAN HYDROCARBON COMBUSTION TUBE BURNER 3 Sheets-Sheet 3 Filed March 17, 1944 Invenior:

Patented Nov. 19, 1946 Wires 3 HYDRUCARBON COMBUSTIOhl TUBE BURNER Rallston M. Sherman, Glastonbury, Conn. Application March 1'1, 1944, Serial No. 526,884

12 Claims. 1

My invention relates to hydrocarbon combustion tube burners.

Heretofore much difficulty has been experienced in providing a combustion tube burner has been experienced in securing a satisfactory uniform distribution of flame about the combustion chamber when it is attempted to use such low density gases as fuel, the flame in burners as heretofore constructed, when supplied with such fuel, tending to be localized at various points along the horizontal extent of the combustion chamber instead of being uniformly distributed along it.

The present invention has among its objects the elimination of the defects of prior burners in the respects above mentioned, burners according to the invention being capable of a wide range of fuel consumption and operating satisfactorily and efficiently throughout such range, and when employing low density gases as fuel securing a uniformly distributed flame.

The invention however-will be best understood from the following description when read in the light of several embodiments of the invention submitted for illustrative purposes, while the scope of the invention will be more particularly pointed out in the appended claims.

In the drawings:

Fig. 1 is a plan of a combustion tube burner accordingto the invention with the combustion chamber cover omitted;

Fig. 2 is a section on the line 22 of Fig. 1 with parts broken away;

Fig. 3 is a fragmentary section on the line 3-3 2 responding to Fig. 2, on an enlarged scale of two further modified burners;

Fig. 11 is a; section, corresponding to Fig. 2, showing a further modified form of burner;

Fig. 12 is a plan of a further modified form of burner with parts in, section and parts broken away and with the combustion tube covers removed;

Fig. 13 isa section on the'line |3-l3 of Fig. with parts broken away; and

Fig. 14 is a fragmentary section on the line 14- M of Fig, 12,

In th embodiment of the invention shown by Figs. 1, 2 and 3 the burner is designed for burning light weight gaseous fuel, that is to say, fuel which has a specific gravity less than that of air. As illustrated, the perforated combustion tubes l' and 3, which are preferably formed of refractory sheet metal such as stainless steel, are cylindrical and are carried in spaced relation to form between them an annular combustion chamber 5. The base supporting the combustion tubes is formed with a bottom wall I having a central opening 9 for admitting air to the space surrounded by the inner combustion tube I. As shown, the base has a peripheral upstanding wall II, and an upstanding wall l3 surrounding the of Fig. 1 on an enlarged scale illustrating the I opening 9, these walls forming between them a fuel groove and being of sufficient height to prevent overflow of oil from the base in case it is desired to convert the burner to one which burns sheet metalv such as stainless steel, which cover is secured at its inner edge by screws I! to said wall, a, compressible gasket I9 of refractory material such as asbestos being provided for rendering gas-tight the joint between the cover and the responding to' Fig. 2, of two modified forms of burners;

Fig. 6 is a section, corresponding to Mg. 2, of a modified form of burner;

Fig. '7 is a fragmentary section, corresponding to Fig. 6, on an enlarged scale showing a detail of a modified burner;

Fig. 8 is a section on the line 8-8 of Fig. 7;

Figs. 9 and 10 are fragmentary sections, cor-- wall. As shown, the cover is provided with a peripheral flange fl which fits and is welded to the inner side of the inner combustion tube i, so as to form a gas-tight joint between them. In this way an endless fuel. chamber 23 is formed in the base, into which chamber the gaseous fuel may be admitted through the opening 25 in the base, this opening communicating with the gas supply pipe El which it will be understood is provided with a valve (not shown) for regulating the amount or gas supplied to the chamber.

As illustrated, at the bottomof the combustion chamber is a sleeve 29 in spaced relation to each of the combustion tubes l and 3, this sleeve being positioned on the base by the three upstandlng lugs 3|, the sleeve, like the combustion tubes, being formed of perforated sheet metal preferably tainless steel.

A pilot burner in the form of a tube 3.3 is shown as positioned in the space between the sleeve 29 and combustion tube l for initially lgniting the gaseous fuel, this pilot burner being supplied with gas through a valve controlled pipe 35 leading from the source which supplies the pipe 21.

In practice, the gaseous fuel supplied the chamber 23 passes from that chamber through the perforations in the combustion tube I which lie below the cover is into the adjacent portion of the combustion chamber 5. The cover iii,

when the screws i? are tightened, presses the lower edge of the combustion tube i againstthe upper surface portion of the bottom wall of the base with sufllcient tightness to insure that all the gas will pass into the combustion chamber through the perforations 31 of the lower end portion of the combustion tube, or at least enough of the gas to insure that the gas distribution in the combustion chamber will be controlled by the size omitted such space is too wide to permit the supand number of the perforationsin said portion of the combustion tube and will not be adversely aflected by passage of an uncontrolled material amount of gas between the base and the lower edge of the combustion tube.

It has been found that when gaseous fuel having a density less than that of air, for example ordinary city gas, is employed in a combustion tube burner as heretofore constructed, the gas because of its pronounced tendency to escape upwardly tends to produce an extremely streaky flame, this commonly resulting in an excess of flame at localized points about the horizontal extent of the combustion chamber with a. very meager flame or no flame at all at other points. By causing the gas to enter the combustion chamber through the perforations of the combustion tube I a uniform distribution of the fuel admitted to the combustion chamber is secured and the flame is uniformly distributed about the combustion chamber.

- It also has been found that with combustion tube'burners as heretofore constructed it is impossible to secure satisfactory and efflcent operation when the burner is turned down to any material extent, the diminished supply -of gas under such conditions causing the flame to flicker, and to wander about the horizontal extent of the combustion chamber. This commonly causes the flame to be extinguished, and aside from that does not result in satisfactory or eflicient operation of the burner. In the present burner, however, the presence of the perforated sleeve 29 avoids these defects and permits the burner to operate satisfactorily and efliciently when the supply of gas is muchdirfiinished. For example, it has been found that when the sleeve 29 is present the minimum eflicient fuel consumption may be about one-eighth the maximum eflicient fuel consumption, whereas with the sleeve omitted it can be only about one-third.

In the above connections it will be observed that the space between the two combustion tubes must be great enough to afford a combustion chamber of sumcient transverse width properly to take care of the higher fuel consumption, and it has been found that when the sleeve 28 is under such conditions becoming so attenuated 1 that at localized points the mixture of it and the air passing through the perforations of the combustion tubes above the cover l5 becomes overlean and burns either inefliciently or not at all; However, when th sleeve 29 is present the gas entering the combustion chamber tends to be confined between the sleeve and the combustion tube I so that the upper portion of that space in effect forms a jet delivering the gas upwardly into the body of the combustion chamber where it burns in th form of a flame F (Fig. 3) uniformly extending about the combustion chamber. outer combustion tube 3 slightly above the upper edge of the upstanding wall H tends to flow downwardly into the space between that combustion tube and the sleeve 29, as indicated by the arrows in Fig. 3, and passes through the perforations in the sleeve to mix with the gas entering the space between the latter and the combustion tube i so that a carbureted mixture discharges from this last mentioned space, it having been found that where the sleeve .29 is imperforate satisfactory results cannot be secured, the flame in such case burning with a so-called dirty yellow" flame.

Satisfactory results have been secured with the burner described, when supplied with ordinary city gas having a. B. t. u. value of about 550 per cubic foot, in which the two combustion tubes and sleeve 29 are provided with perforations 31 about 0.07 inch in diameter arranged in rows inch apart and spaced A inch apart in these rows. Thenumber of rows of perforations establishlug-communication between the chamber 23 and the combustion chamber will vary with the size secured when the sleeve extends upwardly to at least the top of the portion of the cover i5 welded to the combustion tube I.

It will be understood that the combustion tube 3 need not be positioned interiorly of the upstanding wall Ii, but may be supported at its exterior as shown'in Fig. 4. Similarly, the combustion tube I need not extend to the extreme bottom of the chamber 23, as, for example, the tube, which being welded to the cover I5 is supp rted thereby, may adjacent its lower end fit an upstanding circumferential flange 39 projecting upwardly from the bottom wall 1 of the base as shown in Fig. 5, so that as in the construction shown by Fig. 2 the lower end portion of the tube and the base have cooperating portions preventing substantial communication between the chamber 23 and combustion chamber other than by way of the perforations in the tube.

If desired, for admitting additional air to the space between the sleeve 29 and combustion tube 3, the upstanding wall ll of the base may be formed-on its interior with an annular groove 4| Air entering the perforations of the portion 45 of which is frusto-conical and extends downwardly so as to expose sumclent perforations of the inner combustion tube l to admit an increased amount of air into the space between that tube and the sleeve 29 for admixture with the gas in such space.

The burner according to Figs. 6 to 8 is designed for burning either gaseousor liquid fuel selectively. The burner shown by these figures is in general identical with that shown by Figs. 1 and 2 except that an'annular wick't'l is provided in the space between the sleeve 29 and outer combustion tube 3, the wick being spaced from the sleeve to provide an air space 49 between the two so that air may pass through the perforations of the sleeve into the space between the latter and the inner combustion tube I for the reasons hereinbefore described. The wick may be spaced from the sleeve byproviding a suflicient number of lugs iii. More conveniently, however, a number of spaced clips 5i may be secured at their lower ends by welding to the combustion tube 3 for holding the wick in such spaced relation.

As shown in Fig. 6, the gas supply pipe 2'! communicates with an opening 53 in the upstanding boss 56 formed integrally with the bottom wall 1 of the base so as to prevent flooding of the pipe during the starting period of the burner by the oil admitted to the chamber through the opening 57 of the base, with which latter opening communicates the oil supply pipe 59, this latter pipe, like the pipe 2?, being controlled by a valve (not shown) for regulating the amount of oil supplied the burner.

n; will be understood that the lowermost perforations 31 of the inner combustion tube and sleeve 29 of the burner according to Figs. 6 to 8 will be positionedclose enough to the base to permit sufficient oil to reach the wick for the starting of the burner. After the burner has started the oil will be vaporized in the chamber 23, the cover it of which is highly heated by heat reflected against it from the combustion tube l and by heat conducted to it by said tube with which it makes intimate contact. Also, the time consumed in starting the burner when using oil as fuel is much reduced by reason ofthe inner combustion tube l extending into the oil space, the lower portion of the tube being highly heated by heat conducted to it from the cover i5 and from the portions of the tube above that cover, at which portions the flame exists.

It will be understood that, although the sleeve 2% may with advantage be used when burning oil, the vapors of which are heavier than air, the distribution of the fuel tended to be eifected by the perforations of the combustion tube I below the cover it is then of no importance, for such heavy vapors or gases tend to flow like water and distribute themselves, that is t5 say, like water would if admitted through the pipes 59 or 21, they tend to lie at the bottom of the chamber 23. When using such heavier fuels, therefore, it is not necessary to have the lower end of the inner combustion tube i in close proximity to the bottom wall 7 of the base, but it may be spaced therefrom say about 0.1 inch as shown in Fig. 1.0 so that the oil vapors or the heavier gases will flow beneath 'he lower end of the tube into the space between that tube and the sleeve 29. With these oil vapors or heavier gases the effect of the sleeve 29 is not so pronounced as when burning the lighter gases. However, with such vapors and heavier gases the sleeve secures a useful effect in that it permits a greater range of fuel consumpnon than u omitted. It has been found, i'or ex ample, that in an oil burner, in which emcient operation can be secured with no less than about Vs the maximum eiiicient' fuel consumption, by

use of the sleeve eflicient fuel consumption can be" secured with about $41 the maximum efllcient fuel consumption.

In the modification shown by Fig. 11 the annular fuel chamber 6! is positioned at the outer side of the outer combustion tube 3, the space between the upstanding wail II and said tube being closed by the annular cover 63.. As shown,

' the cover is secured to the upper edge of the wall Ii by screws 65, the cover having an inner peripheral flange 61 welded to the tube 3. Also, as shown, the inner combustion tube I is positioned against the inner upstanding wall i3 of the base, and the inner peripheral portion of the cover 63 is depressed at 69 to secure the same effect as the depressed portion 45 of the cover according to Fig. 9. Further, as shown; the inner upstanding wall i3 is provided with an arrnular groove ll corresponding to the groove 41 of Fig. 9for securing the same effect :as the latter. It will also be understood that in the construction shown by Fig. 11 the outer oombustion tube 3 may terminate above the base in the same way as the inner combustion tube i of Fig. 10 for securing the same effect as the latter.

In the modification shown by Figs. 12 and 13 two annular combustion chambers 13 are provided, respectively positioned between the pairs of combustion tubes i and 3. As shown, the base is provided with a bottom wall 15 provided with pairs of upstanding walls l1, 19, the pairs of combustion tubes being positioned between the walls of these pairs and being arranged with relation to said walls as hereinbefore described.

As illustrated, the spaces between the upstanding walls 19 and combustion tubes 3 are closed by covers 8!! welded to said tubes and resting on compressible gaskets 82 positioned on the upper edges of'said walls. As shown, the covers are clamped to the upper edges of said walls by clips 83. connected by clamping screws 85 to lower clips 81, all these clips bridging the spacebetween said walls 19. The walls 19 being in spaced relation permit air to enter the space between the combustion tubes 3, while air enters theinterior of the innner combustion tube I through the opening 89 in the base.

As shown, the burner according to Figs. 12, 13 and 14 is arranged for burning either gas or oil selectively, gas being admitted through the valve controlled pipe ill and oil through the valve controlled pipe 93 for supplying regulated amounts of gas or oil thereto. At spaced points the fuel chambers 95 below thecovers 8| are connected by spoke-like parts 91 integral with the upstanding walls 19, which parts are jperfoe rated as shown at 99 for admitting the oil vapors 'or gas from the inner fuel chamber 95 to the outer fuel chamber 95. As shown, a wick 47 is provided at the bottom of the inner combustion chamber which serves to start the burner when oil is supplied as the fuel.

It will be understood that, within the scope of the appended claims, wide deviations may -be made from the forms of the invention described without departing from the spirit thereof.

I claim:

1. A. gas burner for gas having a density less than air having, in combination, a base carrying a pair of perforated combustion tubes one of which surrounds the other in'spaced relation tion to each of the combustion tubes for dividthereto to form a combustion chamber between them, said base having an opening for supply- -in' communication solely by the perforations of said' tube, the end portion of the latter and said base having 7 cooperating portions preventing other substantial communication between said chambers.

2. A burner according to claim 1 having a perforated sleeve within the combustion chamher at its bottom in relatively widely spaced relaing the bottom portion of said chamber into two relatively wide open top chambers, the fuel chamber communicating with the chamber between said sleeve and the combustion tube adjacent. the fuel chamber.

3. A gas gurner for gas having a density less than air having, in combination, a base having a central-air opening, and, surrounding said opening, spaced upstanding walls extending from a bottom wall of the base to form an endless gaseous fuel groove, a pair of perforated combustion tubes one of which surrounds the other in spaced relation thereto to form a combustion chamber between them, which tubes are carried by said base with the end portion of one of said tubes contactingone of said upstanding walls and the other tube extending into said groove in spaced relation to the other of said upstanding walls, a cover member above the bottom of said groove extending'from the last mentioned upstanding wall to the combustion tube spaced therefrom so as to form an endless gaseous fuel chamber communicating with the combustion chamber solely through the perforations of the last mentioned tube, the end portion of the .latter and said base having cooperating portions preventing other substantial communication between said chambers' I 4, A burner of the character described having in combination, a base having a central 'air opening, and, surroundlngsaid opening, spaced upstanding walls extending from a bottom wall of the base to form an endless fuel groove, a pair of perforated combustion tubes one of which surrounds the other in spaced relation thereto to form a combustion chamber between them,- which tubes are carried -by said base withthe end portion of one of said tubes contacting one of said upstanding walls and the other tube extending into said groove in, spaced relation to the other of said upstanding walls, a cover member above the bottom of said groove extending from the last mentioned upstanding wall to the combustion tube spaced therefrom so as to form an endless fuel chamber. the end of the last mentioned tube being supported in slightly spaced relation to the bottom of said groove to establish communication between saidfuel chamber and the combustion chamber, a perforated sleeve within the combustion chamber at its bottom in relatively widely spaced relation to each of the combustion tubes fol-dividing the bottom of said chamber into two relatively wide open top chambers, the fuel chamber communieating with the chamber between said sleeve and the combustion tube adjacent the fuel chamben',

. 8 I .5. A burner according to claim 3 having a perforated sleeve within the combustion chamber at its bottom in relatively widely spaced relation to each of the combustion tubes for dividtwo relatively wide open top chambers, the fuel chamber communicatingwith the chamber between said sleeve and the combustion tubeadjacent the fuel chamber. v

6. A burner according to claim 3 having a perforated sleeve within the combustion chamber at its bottom in relatively widely spaced relation to each of the combustion tubes for dividing the bottom of said chamber into two relatively wide open top chambers, the fuel chamber communicating with the-chamber between that sleeve and the combustion tube adjacent the fuel chamber, and a wick in the space at theopposite side of said sleeve surrounding the latter in spaced relation thereto.

7. A burner according to claim 4 having a wick in the chamber at the side of said sleeve opposite the fuel chamber, said wick surrounding the sleeve in spaced relation thereto.

8. A burner of the character described having, in combination, a base having a central air opening, and, surrounding said opening, spaced upstanding walls extending from a bottom wall of the base to form an endless fuel groove, .a pair of perforated combustionv tubes one of which surrounds the other in spaced relation thereto to form a. combustion chamber between them, which tubes are carried by said base with the end portion of one of said tubes contacting one member above the bottom of said groove extend-' ing from the last mentioned upstanding wall to the combustion tube spaced therefrom so as to form an endless fuel chamber communicating with the combustion chamber solely through the perforations of the last mentioned tube, the end portion of the latter and said base having cooperating portions preventing other substantial communication between said chambers, a perforated sleeve within the combustion chamber at its bottom in relatively widely spaced relation to said combustion tubes for dividing the bottom portion of said chamber into two relatively wide open top chambers, means for admitting vaporizable liquid fuel or gaseous fuel to said fuel chamber, and a wick within the chamber between said sleeve and the combustion tube remote from said fuel chamber for initiating opsupplied with liquid fuel.

9. A burner of the character described having,

in combination, a base having a central air opening, and, surrounding said opening, spaced upstanding walls extending from a bottom wall I of the base to form an endless fuel groove, a pair of perforated combustionv tubes one of which surrounds the other in spaced relation thereto to form a combustion chamber between them, which tubes are carried by said base with the' end portion of one of saidtubes contacting one of said upstanding walls and the other tube extending into said groove in spaced relation to the other of said upstanding' :wal1s, a cover member above the, bottom of said groove extending from the last, mentioned upstanding wall to the combustion tube spaced therefrom so as to form an endless fuel chamber communilo catin! with the combustion chamber through ing the bottom portion of said chamber into of said upstanding walls and the other tube the perforations of the last mentioned tube, the

end portion of the latter and said base having cooperating portions preventing other substantial communication between said chambers, a perforated sleeve within the combustion chambar at its bottom in relatively widely spaced relation .to each of the combustion tubes for dividing the bottom portion of said chamber into two relatively wide open top chambers, a pilot light device within the chamber between the sleeve and the combustion tube adjacent the fuel chamber, a wick in the space at the opposite side 01 said sleeve surrounding the latter in spaced relation thereto, and means for admittingvaporizableliquid fuel or gaseous fuel to said fuel chamber.

10. A burner of the character described hav ing, in combination, a base; a pair of vertically extending perforated combustion tubes peratively carried at their lower ends by said base with their walls in laterally spaced relation to form between them an annular combustion chamber: a vertically extending perforated sleeve operatively carried by said base within the combustion chamber at its lower end portion in relatively widely spaced relation to each of the combustion tubes for dividing said lower 10 portion of said combustion chamber into two relatively wide open top non-liquid fluid conducting chambers communicating with the portion of the combustion chamber above them; and means for supplying non-liquid fluid fuel to one of said open top chambers for discharge into the portion of the combustion chamber above it through the open top oi. said open top chamher, which means comprises walls forming an annular fuel chamber adjacent said lower portion of said combustion chamber, the last mentioned combustion tube constituting a portion of said walls and defining a side of said fuel chamber.

11. A burner according to claim10 in which the'communication betweenthe annular fuel chambem and one of the open top chambers is established solely by the perforationsln the combustion tube defining a portion of the walls of said fuel chamber.

12. A burner according to claim 10 having an annular wick in the open top chamber at the side of the sleeve opposite the open top chamber which communicates with the annular fuel chamber, said wicl'r being in laterally spaced relation to said sleeve.

RALISTQN M. SHERMAN.

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