US1985920A

US1985920A - Oil burner

Info

Publication number: US1985920A
Application number: US685682A
Authority: US
Inventors: Donald C Elliot; Lancey Warren H De
Original assignee: Gilbert and Barker Manufacturing Co Inc
Current assignee: Gilbarco Inc
Priority date: 1933-08-18
Filing date: 1933-08-18
Publication date: 1935-01-01
Anticipated expiration: 1952-01-01

Description

Jan- 1, 93 D. c. ELLIOT ET AL OIL BURNER Filed Aug. 18, 1933 3 Sheets-Sheet l o o o o 0 o o o o o o o o o o o/ o 0 0 w a o o o o ucooaoooo mgo u o o o o o o o o o o o o 0 o 0 0o 0 o e o 0 0o 0 o o a o o a O O O o oonaoooooooooooonfi o oooo ooooooooooo/ 00000000 000000000 G OOOOOOO OO OO oooooooooooooo fi oOoOoO0uOOOOO0,00/

oooooo aoco onooo 000 00000000000 OOOO O O OO OOOO OOOO Q OOO OO OOOOOOQOOODOOOOOOO O OOOOOO OOOOOOOO OOO OOOOOO DOOO OOOOOOOOOOOOOnvQOO .oooooocoooooooooo I oooooooooooofiooooo a 0 o o o o o o o o o 0 o o o o O 0 O O O O 0 O O O O O O O O 0 0 7 0 O 0 O 0 0 0 O O 0 0 0 0 O 0 GUOO OWOOOOOOO/O oooocoo ooo9-ooooo OOOOO0OOOOOIOOBO maooooooooooooozooo o o o o o o o o o o o o o o o owo owo o o o o o 000 00 oo 0 00000 oooo ooo oaoq oo oooooo OOOOQOOUGO OOOQOO OOOQOOOOOQOOOOOQOQO ar ooo III V! E 7 m d S Ra -u. o N D MR NR I04 DW WY AB z -hmmmll 1 wllllvllllllll ATTORNEYS Jan. 1 1935. D. c. ELLIOT ET AL OIL BURNER Filed Aug. 18, 1953 3 Sheets-Sheet 2 L LE 3% mm: Q W R A 104 N M Patented Jan. 1, 1935 UNITED STATES OIL BURNER" Donald 0. Elliot, West Springfield, and Warren H.

De Lancey, Gilbert & Barker West v Springfield, 'Massachusetts 7 Springfield, Mass., assignors to Manufacturing Company, Mass., a corporation of Application August 18, 1933, Serial No. 685,682 17 Claims. (01. 158-87) This invention relates to improvements in oil burners of the so-called combustion tube type.

Burners of this type have been widely used heretofore in relatively small sizes for stoves, kitchen ranges and the like but they have not come into use to any great extent for furnaces and boilers used for general house heating purposes. This invention is more particularly concerned with the provision of a burner of the general type described, but in a relatively larger size, which is specially designed for the last-named purpose.

An object -of the invention is to provide in a burner of the aforesaid type, having a vaporizing chamber in which oil may be converted into vapor and from which the vapor is supplied to certain of the combustion chambers of the burner; an intermittently operable means to supply liquid fuel to said chamber; and an independent means for supplying fuel to another of the combustion chambers to maintain therein a constant fire for the purpose of maintaining said chamber at a temperature such as to readily vaporize the oil when the-same is supplied thereto by said intermittent means. The arrangement provides a burner of the high-low fire type and is characterized by the disposition of the vaporizing'chamher with respect to the low-fire section of the burner to maintain the chamber atvaporizing heat during the so-called idle intervals when the burner is not operating onfull fir Another object of the invention isto provide in a burner of .the type just described, provisions for increasing the fire in the "low fire combustion chamber, whenever there is a demand for heat from the burner, by admitting vapor to such chamber from the vaporizing chamber. This increase in the'low fire is desirable as such fire is relied on to ignite the vapor in the other combustion chambers. The provisions are also usefull in that the low fire can be expanded the better to help satisfy the demand for heat.

The invention also has for an object the provision of means for vaporizing the fuel at relatively low temperatures such as to avoid, asfar as possible, cracking of the oil with the resultant deposit of carbon residue of a hard, flinty, cokelike character. To this end, the vaporizing chamber or'chambers are located below the combustion chambers of the burner and out of the, zone ofhigh temperatures and the-vapor is produced from the surface of a pool of boilingoil, as distinguished frdm feeding it drop by drop on a surface so hot that theoil is instantly vaporized by a process which is virtually that of destructive distillation.

A further object of the invention is-to provide in a burner of the class described a novel means for separating from the vapors as they leave the 5 vaporizing chamber, the heavier unvaporized constituents which are entrained with such vapors and causing such constituents to be precipitated in a receptacle which may readily" be removed and cleaned. The residue, thus collected, is in 10 the nature of a soft sludge and the receptacle in which it is collected may be readily cleaned by wiping with a cloth, as distinguished from the usual case where the residue is hard and flintv and has to be removed by scraping.

The invention also provides'a burner in which the fuel grooves in the burner baseandthesupply conduits leading from the vaporizing chamber to such grooves will be substantially free from carbon deposits in operation. The grooves, which 20 serve the high-fire combustion chambers, receive nothing but vaporized fuel and this is also the normal condition with respect to the supply conduits for such grooves. 1 The groove,'which serves the low fire combustion-chamber,'might accumu- 25 late carbon if, like the usual'stove burner, the fire was maintained only intermittently in said chamber, because carbonization occurs largely during the lightlngperiod when the oil is burning at the wick. However, in this burnerthe low fire, 30 once started, normally continues during the entire heating season and asa practical matter there is very little vaporization of oil in the .low fire groove and thus no' substantial-amount of carbon is formed therein.

Other objects and advantages will appear as the detailed description proceeds and will be pointed out in theappended claims. V

The invention will be disclosed for illustrative purposes with reference to the accompanying 40 drawings, inwhich:

Fig. 1 is a sectional elevational view of one form of burner embodying the'invention;

Fig. 2 is a fragmentary sectional view thereof taken on the line 2-2 of Fig. 3; v

Fig. 3 is a plan view of the burner base as it appears after'the several combustion tubes andthe cover have been removed;

Figs. 4 and 5 are sectional plan views taken on the lines 4-4 and 5-5,,respectively, of Fig. 1;

.Fig. 6 is a plan view, taken similarly to Fig. 3

i but showing aimodified form of the burner base';

- vided with a. dam 19 the essential elements of the fuel feeding means for the burner.

Referring first to the form of the invention shown in Figs. 1 to 5 inclusive, the burner includes a base B, usually a casting, which is formed with a plurality of endless fuel grooves, usually but not necessarily circular. These grooves are arranged one within another in concentrical and air-spaced relation. As herein shown, the innermost groove, marked 11, is supplied with oil by way of a pipe 12 (Fig. 2), and the other grooves 13 are supplied with vapor by way of a plurality of vapor conduits 14 (four as shown in Fig. 3). The vapor conduits 14 are formed integrally with the base in underlying relation with the grooves and serve to tie together the bottom walls 15 of the several grooves. They are connected to a single vaporizing means, later tobe described. Ports 16 extending through the bottom walls 15 of the grooves 13 connect the same with the underlying vapor conduits 14.

As shown in Fig. 3, two diametrically opposite conduits 14 are each connected by ports 16 with the innermost and the outermost of the vapor grooves 13 while the other two conduits 14 are each connected by ports 16 to the outermost and intermediate vapor grooves '13. This arrangement of connections between the several vapor grooves and the underlying supply conduits has been found by experiment to result in an excellent distribution of vapor, the outermost and longer groove having four supply ports 16 and the intermediate and inner grooves having two ports each. While the described arrangementhas been found desirable and is important and at present preferred, nevertheless it is susceptible to variation and it is not intended to limit the invention thereto.

The inner oil groove 11 contains a wick 1'? of suitable form and its supply pipe 12 is connected to the bottom wall of the groove as shown in Fig. 2. It is intended to maintain a constant fire in the combustion chamber, of which groove 11 forms the lower part, and to supply intermit tently, as and when required, oil vapor to the grooves 13. Such constant fire serves to maintain the vaporizing provisions warm and is utilized also to ignite the vapor in grooves 13. For the latter purpose, and that only, the several grooves 13 are interconnected, and the inner groove 13 connected to the oil groove 11, at one or more points (two as shown in Fig. 3) by a series of radial and aligned conduits 18. These conduits afford firing ports,-enabling the vapor from the several grooves 13 to pass'into the groove 11 and be ignited and, by the flash back of the flame, to initiate combustion in the several grooves 13. Each inner conduit 18 is pro- (Fig. 2), the crest of which level of oil in groove 11. 11 cannot pass into lies above the maximum Consequently, oil from groove any of the vapor grooves 13.

The base affords a pair ofradi'ally-spaced, circular boundary walls 20 upstanding from the bottom wall 15 of each of the grooves 13 and 11 and these walls are shouldered as shown to receive the lower ends of perforated combustion tubes 21,-one pair for each groove and affording therebetween a combustion chamber 22. Between each tube of one pair and the'adjacent tube of the next pair is an intermediate air chamber 23 and arcuate openings 24 (Fig. 3),'

formed in the base B, admit air to the base of Within is a central air chamber 25'into the lower end the innermost tube 21 of which air can enter by way of the openings 26 (Fig. 3). A cover 27 of any suitable form, caps the several tubes 21 and has openings 28 overlying the combustion chambers 22. This cover closes off the upper ends of the several intermediate air chambers 23 and may likewise close off the upper end of 25, although it is preferred to provide a central opening 29 in the cover to allow escape of air therethrough.

The burner base, thus described, is supported in any suitable way, as for example, by a series of posts 30 from a base plate 31. Preferably, the support should be adjustable to vary the height of the burner base and also to enable it to be leveled. For this purpose, the posts 30 are connected to the base plate 31 by set screws 32, whichenable the vertical adjustment, and, if necessary or desired, they may also be screw threaded into the hubs 33 of the burner base, to which hubs they are connected at their upper ends.

The novel vaporizing provisions will next be described. The inner ends of the four conduits 14 are integrally united to a cylindrical housing 34, which is located centrally of the fuel grooves but wholly below the horizontal plane of the bottomwalls 15 of such grooves. This housing depends from the inner ends of the conduits and lies wholly outside and below the inner air chamber 25. In the upper portion of this housing is formed a vapor distributing chamber 35, with which the several conduits 14 communicate at their inner ends, as will be clear from Figs. 3 and 4. Chamber 35 is permanently closed at its upper end by a top wall 36, formed as an integral part of the housing. Another integral part of the housing forms a bottom wall 37 for the chamber, having a central opening, in which is suitably fixed a tube 38, depending into the lower part of the housing. Qil vapor rises through this central tube 38 into the chamber 35 and is then distributed by the several conduits 14 to the several vapor grooves 13. The space within. the lower part of housing 34 is subdivided by an upstanding cylindrical tube 39 into an outer annular chamber 40 and an inner cylindrical chamber 41. The smaller tube 38 extends downwardly into the larger tube 39 so that the two partially overlap to prevent any direct passage from the outer chamber 40 to the tube 38. Communication between chamber 40 and tube 38 is established only by way of the upper part of the irmer chamber 41. Oil is supplied to the outer and annular chamber 40 by way of a pipe 42. Normally, this chamber is filled with oil close to the upper edge of tube 39. Normal vaporization (except during the starting period) is effected entirely in the well 40 and the vapors are deflected downwardly into the inner chamber 41 before being able to leave by way of tube 38. The important point is to provide means for forcing the vapors to turn and pass over if not into the chamber 41 in order to throw down any relatively heavy unvaporized fractions of the oil. This result may be obtained without the overlapping of

tubes

38 and 39, as will later appear.

The residue from the vaporization, in the form of a soft sludge, is intended to be thrown down into chamber 41. The sludge chamber 41 can be cleaned from moving tube 39. The lower end of this-tube is telescoped over and suitably fixed, as by a frictional fit, to an upstanding boss 43, formed on a removable plate 44, which forms a bottom clothe central air chamber v g V 1,985,920

sure for the housing 34 and is suitably secured thereto, as by the nuts 45 threaded onto studs 46, secured as indicated in the housing 34. A gasket 47 is preferably applied between plate 44 and the bottom face of housing 34 to seal the joint.

Normally, vaporization occurs at the surface of the oil in the deep oil well afiorded by the annular chamber 40 by the heat derived from the burner and conducted to the cylindricalwall of housing 34. The constantly burning fire in the inner groove 11 keeps the housing warm'but necessarily not so warm as when the burner is operating with combustion in all the chambers 22. To secure a quick response, when the oil supply to well 40 is turned on, it is desirable to provide additional heating surface to function at that time. For this purpose, a rod 48 suitably secured to the upper wall 36 of the vapor distributing chamber 35, extends downwardly through such chamber and through tube 38 into the central chamber 41. When the oil;supply to well 40 is first turned on, the cylindrical wall of housing 34 is not hot enough to vaporize the oil at as rapid a rate as that at which it is supplied through pipe 42. Consequently, oil will overflow from well 40 into the central chamber 41 and it is then that the rod 48 comes into action and vaporizes such oil as overflows into chamber 41. After the burner has been operating a short timewith combustion in all the grooves 13, the oil in chamber 41 will have been completely vaporized and the rod 48, no longer'functions. Then all vaporization occurs in the outer chamber 40 and the oil is then vaporized at a rate substantially equal to that at which it is supplied so that the oil level remains substantially constant at. or close to, the upper edge of tube 39. A

A second and preferred form of the invention is shown in Figs. 6 and 7. In this form, a plu-1 rality of vaporizing units are employed instead of the single one heretofore'described. One important object here is to locate the vaporizing provisions as closely as possible to the inner groove 11, and its associated combustion chamber 22, in which a constantly burning fire is maintained. By. removing the vaporizing provisions from the central location, heretofore described, and moving them into close relation with the walls of the inner groove 11, more heat 'is derived, duringlow fire operation of the burner to keep the vaporizing provisions in condition for quick response, when the main supply of fuel for high fire operation is turned on. There is no serious difiiculty in securing heat enough for effective vaporization during high fire operation. The real problem comes in maintaining the .vaporizing provisions warm enough during the idle period or rather the period of low fire operation of the bumer. And this problem has been solved by locating the vaporizing provisions so that they underlie, at least in part, the inner groove 11, or whatever groove is chosen for the low fire operation. When the vaporizing provisions are thus located, it-will usually be found necessary, or at least desirable, to provide more than one unit in order to secure proper distribution of the vapor to the grooves. Two or more of such units may be used, depending on how many are necessary to meet the particular conditions encountered. The two shown, or more if required, are deemed desirable in order to secure a .balanced arrangement which will result in a sufiloiently even distribution of vapor to the several grooves. One unit. alone would not, it is thought, be as satisfactory, when disposed inthe offset relation shown.

Referring to Figs. 6 and 7, the burner base and Vaporizers only are shown. It will be understood that combustion tubes and a cover are used,

as shown in Fig. 1, and that the burner base is suitably supported, as for example as shown in Fig. 1. The burner base B involves the same general arrangement of grooves as heretofore described, and the parts in Fig. 6 which correspond to parts in Fig. 3 have been given the same ref erence numerals.

.of fuel through a pipe 12. This groove 11, as before, is connected to the three vapor grooves 13 by two series of aligned firing ports 18, solely for ignition purposes. A section taken through the upper series of firing ports 18 of Fig. 6 will look exactly as shown in Fig. 2 and a, section through the other series will look the same except for the omission of the oil pipe 12. A hub 50 is, however, provided at the inner end of the inner port 18 of the lower series to enable attachment of an oil feed pipe such as 12 at that location if desired, or at that location as an alternative to the location shown. These two series of firing ports are located in diametrically opposite relation. Located at. ri ht. angles thereto are two vapor conduits 14' formed as integral parts of the burner base and each extending in underlying relation with the several grooves from the outermost to the innermost thereof, .and each opening at its inner end into a vapor distributing chamber 35'.

The two vapor distributing chambers are disposed at diametrically opposite points with respect to the low fire groove 11 and partially'underlie the same, Each chamber 35', asbefore, is formed in the upper part of a hollow cylindrical member 34* which is formed integrally with the burner base and depends therefrom. The lower wall 37' of chamber 35' has a central vapor inlet byway of a conduit 38', fixed to and depending fromsuch wall. The space within member 34' and below wall 37' is subdivided as .before, by a sleeve 39' into an outer and annular vaporizing chamber 40' and an inner sludge-collecting chamber-.41. The sleeve 39' is mounted as before on --the removable closure plate 44' for the lower end of member 34. However, such plate is held in place by a single nut 51, threaded onto the lower endof a rod 48', which passes through plate 44,

chamber 41', conduit 38', and distributing chamber 35', and is threaded into, or otherwise suitably fixed in, the upper wall 36' of chamber 35. This rod 48 performs the same function as rod 48 and in this case has simply been extended down wardly to serve also as a retaining boltfor plate 44'; Oil is fed into each chamber 40 by a pipe.42'.

The operation of each vaporizer is the same as heretofore described and the only important difference between the vaporizing provisions of Figs. 1 and 7 is one of location. The sleeves 39' and 38' are, however, arranged slightly difierent than the corresponding elements of Fig. 1 in that they do not overlap. Having in mind the purpose of these elements, which is to force the vapors from-chamber 40' to make a sharp turn in passing to the outlet conduit 38' in order to 'throw down residue into chamber 41", it will be clear that this purpose can be accomplished without overlapping of the parts 38' and 39'. As shown in Fig. 7, the lower edge of member 38' and the upper edge of member 39' lie in the same horizontal plane. This arrangement gives excellent results and The inner groove 11, as before, has a wick 17 and is fed with a constant supply" avoids any chance of trapping vapor during early stages of operation. For example, if the liquid rising in well 40 (Fig. 1) and overflowing into chamber 41 should fill the latter, vapor woulddye trapped in the annular space between conduit 38 and wall 34. With vaporization occurring in well 40, the vapors would accumulate in said space and be compressed until placed under sufilcient pressure to force down the level of oil in chamber 41 and allow escape of vapors up conduit 38. As soon as the pressure is thus relieved, the liquid might rise in chamber 41 and agaln'trap vapor as described. The result under such conditions would be a flow of vapor in surges through conduit 38 rather than in the even, steady flow desired. The arrangement of Fig. 7 avoids any possibility of trapping vapor and causing a surg-.

ing. flow thereof.

As an alternative or as an additional means for avoiding the trapping of vapor, as described, one or more narrow slots 52' (two as shown) may be cut in the sleeve 38' to provide a'constant by-pass of restricted area. The area of this by pass is so small as not to seriously interfere with the desired result of deflecting the vapors over cup 41 tc cause the heavier constituents to be precipitated. At the same time, these slots serve to prevent the trapping of vapors and the building up of pressure on the vapor such as would result in a'pulsating and uneven flow of vapor to the combustion chambers. It will be obvious that the same expedient might be used for the same purpose with the form of burner shown in Fig. 1.

The conduits .14 are connected to the several grooves 13 by ports, such as 53, 54, and 55. The outermost ports 55, opening into the outermost groove13, are of the largestarea, the intermediate ports 54 are of less area, and the innermost ports 53 are of the least area. These ports are of graded size to control the distribution of vapor to the several vapor grooves by dividing the flow from each conduit 14' in three such parts so that each groove 13 will receive its proper shareof vapor, more being required for the outer groove, less for the intermediate groove and the least for the innermost groove.

In Figs. 6 and "I, there are shown provisions for expanding the fire in the low-fire" combustion chamber served by' groove 11. These provisions are optional. The burner will function efiectively but they are nevertheless desirable,

without them, at least in some cases, and have distinct advantages. The provisions, referred to, consist simply of a passage, such as 56, extending through the bottom wall-of groove 11 to enable communication between each conduit 14' and the groove. A dam 57 is provided, with its crest above the maximum level to whichoil can ever rise in groove 11, to prevent any possibility of oil flowing from the groove into the underlying vapor conduit 14. The'wick 17 is cut away, as indicated, to clear this dam. The result of this arrangement is that, whenever there is a demand for heat and oil is admitted to the vaporizing chambers, some of the vapor produced is admitted to groove 11 and the size of the fire in the overlying combustion chamber is increased. The fire is increased at the time when it is needed for the purpose of igniting the vapor admitted to the grooves 13. Thus. these provisions are useful for ignition purposes in the same sense that it is useful to expand the'fiame of a gas. pilot for ignition purposes. And these provisions are also useful for the reason that the inner combustion chamber can be made to produce a larger tire and help operation to follow,

to a greater extent than it would otherwise in satisfying the demand for heat. A lower degree of low fire can be maintained and expanded whenever necessary to satisfy heat requirements. The arrangement is more efiicient because it enables a reduction in the amount of oil used to supply the constantly burning fire. Obviously,

the same provisions can be incorporated in the burner shown in Fig. 1. If deemed necessary or desirable, the grooves 13 may be provided with wicks just as is done in the case of groove 11. The onlyuse for such wicks would be to assist in originally heating up the burner because in normal operation no oil enters grooves 13. The wicks are not strictly necessary, as will be clear from the description of but in some cases they are desired by the customer and are then provided.

A fuel supply for the burner, including a level control therefor and regulating valves to control the rates of flow for both high and low fire, together with a means for turning on and off the high fire, is shown in conventional form in Fig. 8. The provisions shown in Fig. 8 will serve equally well for either form of burner. The oil supply to the groove 11 and to the vaporizing well 40 or wells 40', is effected by gravity flow from a constant level source, such as the chamber 60 to which the described

pipes

12 and 42 or 42' are connected. Oil is supplied to this chamber by gravity flow or otherwise, from a main source of supply, shown in part at 61, by way of a pipe 62.

A valve 63 controls the communication between pipe 62 and chamber 60'and is operated by a float 64 in the chamber, so as to maintain oil at a substantially constant level in the chamber. The level maintained in this chamber is just above the bottoms of the grooves and below the crest of dam 19. The flow of oil through pipe 12 may be regulated by a valve 65, or in any other suitable way. A constant fiow through this pipe is, however, maintained so that there is always oil burning in groove 11, or at least during the heating season. The flow through pipe 42 or 42' to the vaporizing well or wells is regulated by a valve 66 or in any.other suitable way and such flow may be turned on and off by a valve 67 operated by a solenoid 68. This solenoid may be controlled in any desired way, as for example by a room thermostat 69 which will open and close the circuit '70 to solenoid 68, accordingly as the room temperature is above or below a predetermined temperature. The valve 67 is normally entirely closed and is opened by the energization of solenoid 68 when thermostat 69 calls for heat.

The operation of the burner will next be described. In starting up the burner for the first time, or after a period of idleness during which the oil supply to groove 11 has been shut oil, the preferred procedure is to admit oil into groove 11 up to the level described, ignite the oil saturated wick 17 and allow the oil to burn until the base B or B, as the case may be, has become heated to as high a temperature as is possible with the fire available. It is possible to accelerate this initial heating of the burner base by providing wicks in the grooves 13 and admitting oil to these grooves, as in the case of groove 11, so that combustlon will occur in all four of the combustion chambers 22. But this is not the planned mode of operation and it is not necessary to resort to such mode of operation to start the burner. In either case, the combustion is initiated in the usual way, the oil burning at the wick until the walls of the groove have been heated enough to.

vaporize the oil. Thereafter, the oil vaporizes in the groove at a rate substantially as great as that at which it is fed in and the normal combustion then occurs in which the vapor burns with a blue flame starting from a point above the wick and without smoke or odor. The groove 11 is tion chamber 22, the main supply of oilmay then be turned on, either automatically as described or otherwise. The vaporizing

wells

40 or 40 will fill with oil-and initially oil will.overflow into the inner chamber 41 or chambers 41. The

'heated walls 34 or 34' will vaporize oil in wells 40 or 40' and at the same time the members 48 or 48' will vaporize oil in the chambers 41 or 41'. Thus, initially there is available a relatively large area of heated surface which is effective for vaporizing the oil. And it is important to have the extra area of vaporizing surface such as that afforded by-members 48 or 48'. The larger area of vaporizing surface will produce the requisite amount of vapor at the lower temperature available at the time of starting the high fire. The vapor, thus produced, passes up through conduits 38 or 38' into the distributing chambers or 35' and is distributed by the

conduits

14 or 14 and the

ports

16 or 53, 54 and 55 to the several burner grooves 13. Some of the vapor will pass through the ports 18 into groove lland become ignited from the fire maintained in the inner combustion chamber 22 and this ignited vapor in the firing ports 18 will in turn ignite the vapors in grooves 13. In this way,.combustion very quickly ensues in the whole burner.

As combustion occurs in grooves 13, the temperature of the burner base increases and the oil isvaporized at a faster rate and eventually at a rate substantially equal to that at which it is supplied to the vaporizing wells 40- or 40'. It will be clear that after a short time oil, will cease to overflow from the vaporizing wells 40.

or 40' into the inner sludge chambers. 41 or 41' and that the oil in these chambers will soon be exhausted by vaporization from the rods 48 or- 48', except for the heavy constituents in the base of these chambers, representing the residue collected as the result of previous vaporizing operations. .As the temperature ofthe burner base increases, the vaporizing surface effective to vaporize oil decreases until eventually the rods 48" or 48' ceaseto function and only the surface of member-34 remains effective for the purpose,. This is the normal operation,all oil being vaporized'in the wells 40 or 40' and at a rate such that there is no overfiow into chambers 41 or 41'. The level of oil in wells 40 or 40' may drop below the upper edge of

sleeves

39 or 39 and does not necessarily remain exactly at the level of such edge nor exactly constant at any level. The level of oil in the wells may vary from time to time as is necessary to the accomplishment of the work in hand which is to vaporize the oil in the

wells

40 or 40 without overflowing them and at substantially the same rate as the oil is supplied thereto. If the levelof oil in the well is at the upper edge of

sleeve

39 or 39, then there is available the maximum amount of surface for vaporization and the rate of vaporization may then exceed the rate of oil supply. As a consequence, the oil level will drop slightly and this results in a decrease in area of effectivevaporizing surface and also in a drop in temperature, wherefore the rate of vaporization is diminished. The level of oil may then rise slightly and additional area of vaporizing surface and an increase in temperature thereof will become available to speed up the rate of vaporization. The level of oil may fluctuate in this manner until the proper balance is effected between the heated surface available for vaporization and the rate of oil feed. It is to be noted that the temperatures drop rapidly from the top to the'bottom of the

walls

34 or 34. For example, from the top to the bottom of

wells

40 or 40 there is a temperature drop of from 150' to 200 degrees. Thus a slight drop in oil level will effect a material decrease in the rate of vaporization due to the lessened temperature of the vaporizing surface as well as the lessened area thereof which is effective for order to keep the Vaporizers warm. The oil in these Vaporizers will soon become exhausted after the supply thereto has been cut oil. and the generation of vapor will stop and combustion will cease in grooves 13. The temperature of the burner base will drop materially because of'the decrease in the extent of the fire but the parts.

will nevertheless be maintained warm enough, especially with the arrangement shown in Figs. 6 and 7, so that vaporization will start rapidly when the main supply of oil is again turned on.

The vaporization is effected at relatively low temperatures,that is temperatures well within thedistillation range for the particular grade of oil used. For example, if the distillation range for the particular oil being used is from 325 to,

520 degrees, then the temperature-of-wall 34 at the top of wells 40 or 40' willbe kept within this range. To do this, it is essential that the vaporizers be located belowthe level of theoil groovesbecause (the temperatures at such grooves are,

much in excess of said range. This vaporization of the oil at low temperatures, such as those mentioned, is particularly desired in order to avoid as far as possible cracking of the oil and thethrowing down of residue of a hard, flinty, cokelike nature, whichis difficult to remove and usually has to be scraped or chipped-off. In the ordinary range burner, wherein the vaporizing chamber is located in the central chamber 25 at or above the level of the grooves 11 and 13, oil is vaporized drop by drop as fast as it enters. A drop of oil lodging onanextremely hot surface is instantly vaporized by a proeessof destructive distillation and the hard, flinty residue is thrown down. In the present case, vaporization is effected from the surface of the boiling liquid and there is.not the same action at all. No residue, of the, type requiring scraping to remove, is accumulated. On the contrary, the residue is of a soft, sludge-like nature and can be removed by wiping the parts with a cloth. A most important pointis the means employed to precipie tate the heavier constituents and'cause them to be collected in chambers 41 or 41'. Due to the mechanical disturbance of the oil from the boiling thereof, the heavier constituents, which will not vaporize at the low temperatures used, are entrained with the vapor and carried away from the wells 40 or 40'. There is no collection of sediment in such wells. It becomes necessary to separate these heavier constituents from the vapor because if they were carried along with the vapor into zones of higher temperature, as in the conduits 14 or 14', they would be cracked and in part thrown down as residue, whereas the object hereis to entirely avoid carbon deposits in the grooves 13 and conduits 14 or 14'. To effect the desired separation, the vapors are forced to change their path from the vaporizing wells to the outlet conduits 38 or 38', and the heavier constituents sink into chambers 41 or 41' while the lighter constituents, the vapors, rise through conduits 38 or 38'. The liberated heavier constituents are thus precipitated into chambers 41 or 41 and are there collected. Whenever necessary, these chambers may be removed, quickly and conveniently, with the base plate 44 or 44' emptied, wiped clean with a cloth and replaced.

The invention provides a burner which is substantially free from carbon troubles. Oil does not reach the grooves of the burner in normal operation. Only vapor is supplied to grooves 13 and conduits 14 and the same is true of groove 11 except during the intervals when'combustion is started therein. Normally, the low fire, once started, will burn continuously for the entire heating season and, as pointed out above, this groove 11 normally burns vapor, the oil being vaporized in pipe 12. Thus, the burner proper receives nothing but gaseous fuel during normal operation and is thus free from the possibility of carbon trouble. All the residue is collected in the chambers 41 or 41' and these are readily removable for cleaning and are quickly and easily cleaned.

The invention has been disclosed herein, in an embodiment at present preferred, for illustrative purposes but the scope of the inventionis defined by the appended claims rather than by the foregoing description.

We claim:

1. In an oil burner, a vaporizer comprising, a housing closed except for an outlet in the upper end for vaporized fuel and an inlet in its side for liquid fuel, said housing having a removable bottom wall, a tube mounted on said wall in upstanding relation and having its upper end spaced below thev upper end of the housing and underlying said outlet, said tube subdividing the interior of said housing into an outer chamber which receives said liquid fuel and in which such fuel is vaporized and an inner chamber which receives the residue precipitated from the vapor as such vapor passes over the inner chamber to reach said outlet.

2. In an oil burner a vaporizer, comprising, a housing having within it a partition subdividing it into'upper and lower chambers, and a second partition which subdivides the lower portion of the lower chamber into an inner residue collecting chamber and an outer vaporizing chamber encompassing "the inner chamber, said inner and outer chambers being in communication at points above the second and below the first partition, a vapor outlet conduit fixed to the first partition and depending therefrom toward the second partition with its open lower end in overlying relation with the inner chamber, a rod fixed to the upper end of said housing and extending down- .upper wall wardly through the upper chamber and said conduit and into said inner chamber, and means for supplying liquid fuel to said outer chamber, said housing having a vapor distributing conduit communicating with said upper chamber.

3. In an oil burner, a vaporizer, comprising, a closed casing, a tubular member extending upwardly within the casing from the lower wall thereof and having its upper end spaced below the upper wall of said casing, said member affording within it a residue collecting chamber and outside it avaporizing chamber which communicates with the first chamber above the upper end of said member, means to'feed oil into said outer chamber, and an outlet conduit for vapor extending from said upper wall downwardly into the inner chamber in spaced relation therewith.

4. In an oil-burner, a vaporizer, comprising, a closed casingla tubular member extending upwardly within the casing from the lower wall thereof and having its upper end spaced below the upper wall of said casing, said member affording within. it a residue collecting chamber and outside it a vaporizing chamber which communicates with the first chamber above the upper end of said member,-means to feed oil into said outer chamber, and an outlet conduit for vapor extending from said upper wall downwardly into the inner chamber in spaced relation therewith, and an opening of relatively small area as compared with the area of said conduit formed in the wall thereof at a point above the upper end of said member.

5. In an oil burner, a vaporizer, comprising, a closed casing, a tubular member extending upwardly within the casing'froin the lower wall thereof and having its upper end spaced below the upper wall of said casing, said member affording within it a residue collecting chamber and outside it a vaporizing chamber which communicates with the first chamber above the upper end of said member, means to feed oil into said outer chamber, and an outlet conduit for vapor extending from said upper wall downwardly with its lower end. disposed in the same horizontal plane as the upper end of said member.

6. In an oil burner, a vaporizer, comprising, a closed casing, a tubular member extending upwardly within the casing from the lower wall thereof having its upper end spacedbelow the of said casing, said member affording within it a residue collecting chamber and outside it a vaporizing chamber which communicates with the first chamber above the upper end of said member, means to feed oil into said outer chamber, and an outlet conduit for vapor extending from said upper wall downwardly with its lower end disposed in the same horizontal plane as the upper end of said member, and an opening of relatively small area as compared with the area of said conduit formed in the wall thereof at a point above the upper end of said member.

7. In an oil burner, a base member and perforated walls extending from said member and forming between them a combustion chamber.

said chamber being closed at one end by said member and receiving its air supply through the perforations in said walls, a. housing connected with said member and located wholly below the combustion chamber, said housing affording within it an upper vapor distributing chamber and a lower chamber, a conduit for vapor communicating with said upper chamber and said combustion chamber near the closed end thereof, a partition extending from the bottom of said housing upwardly in said lower chamber toward but not to the top thereof and sub-dividingthe same into an outer oil well and vaporizing chamber and an inner residue collecting chamber encompassed by said outer chamber,- a conduit extending from the vapor distributng chamber downwardly toward the inner chamber with its open lower end overlying the same, whereby the vapor from said'outer chamber is forced to travel over the inner chamber in order to reach said last named conduit, and means for supplying oil to said outer chamber.

8. In an oil burner of the combustion tube type and in combination with the base member thereof and the fuel channels provided in said member, a hollow cylindrical housing depending from said base, a partition subdividing the'interior of said housing into an upper vapor distributing chamber and a lower chamber, a conduit from said upper chamber to said channels for distributing vapor thereto, a; tube the outside diameter of which is less than the internal diameter of said housing mounted on the lower wall of the latter and extending upwardly toward but terminating short of said partition and affording between it and the cylindrical wall of said housing a vaporizing chamber, means to feed oil into the vaporizing chamber, and a conduit of less diameter than said tube extending from said partition downwardly toward said tube with its open lower end overlying the tube.

9. In an oil burner of the combustion tube type and in combination with the base member thereof and the fuel channels provided in said mem-- ber, a hollow cylindrical housing depending from said base, a partition subdividing the interior of said housing into an upper vapor" distributing chamber and a lower chamber, a conduit from said upper chamber to said channels for distributing vapor thereto, a tube the outside diameter of which is less than the internal diameter of said housing mounted on the lower wall of the latter and extending upwardly toward but terminating short of said partition and affording between it and the cylindrical wall of said housing a vaporizing chamber, means to feed oil into the vaporizing chamber, a conduit of less diameter than said tube extending-from said partition downwardly toward said tube with its open lower end overlying the tube, and a heat conductor fixed in the upper wall of the housing and extending through said vapor distributing chamber and last named conduit into said tube.

10. An oil burner, comprising, a base member provided with a plurality of endless fuel distributing channels firanged one within another in air-spaced relation, pairs of foraminous walls one pair for each channel extending from said member and afiordingbetween them combustion chambers, a vaporizing chamber connected to the bottom wall ofone of said channels and depending therefrom, continuously operable means to supply oil to said channel and maintain a continuous fire in the combustion chamber associated therewith for the purpose of heating said vaporizing chamber, a conduit for vaporized fuelextending from said vaporizing chamber to the other of said channels, and means intermittently operable as required to supply oil to said vaporizing chamber to be vaporized, said base provided with a passage interconnecting said several channels, whereby when vapor is fed thereto such vapor may pass to said one channel and be ignited from the fire maintained therein.

11. In an oil burner of .the combustion tube type, a base having a plurality of endless fuel channels disposed one within another in airspaced relation, means for supplying vaporized fuel as and when required to certain of said channels, means for continuously supplying liquid fuel to another of said channels, conduits bridging the air space between said channels and interconnecting the same for the passage of vapor from one vapor channel to another and to said channel to which liquid fuel is supplied, and a dam at the mouth of that conduit which opens into the last named channel having its crest located above the maximum oillevel in said last named channel.

12. An oil burner, comprising, a base having a plurality of endless fuel channels disposed one within another in air-spaced relation, pairs of foraminous walls one pair for each said channel extending from opposite sides thereof and forming therebetween combustion chambers, a vaporizing chamber connected to said base and deriving heat therefrom to vaporize the oil, means operable intermittently as and when required to supply oil to said vaporizing chamber, a conduit connecting said vaporizing chamber to certain of said channels to distribute vapor thereto, means operable continuously to supply oil to another of said channels for the purpose of maintaining continuously a low fire to maintain said vapor izing chamber warm, and connections from the several vapor channels to the last named channel enabling vapor to pass to the latter and be ignited from said low fire.

13. An oil burner comprisng, a base having a plural't-y of endless fuel channels disposed one within another in air-spaced relation, pairs of foraminous walls one pair for each said channel extending from Opposite sides thereof and forming therebetween combustion chambers, a vaporizing chamber connected to said base and deriving heat therefrom to vaporize the oil, means operable intermittently as and when required to supply oil to said vaporizing chamber, a conduit connecting said vaporizing chamberv to certain of said channels to distribute vapor thereto, means operable continuously to supply oil to another of said channels for the purpose of maintaining continuously 'a low fire to maintain said vaporizing chamber warm, and connections from the several vapor channels to the last named channel enabling vapor to pass to the latter and be ignited from said low fire, and an opening from the last named channel into said vapor conduit enabling an expansion of said low fire at the time when the same is used for ign'ition purposes.

14. An--oil burner, comprising, a base having a plurality of endless fuel channels disposed one within" another in air-spaced relation,v pairs of foraminous walls one pair for each said channel extending from opposite sides thereof and forming therebetween combustion chambers, means operable continuously to supply oil to one of said channels to maintain in the combustion chamber associated therewith a fire suflicient to maintain said base at vaporizing heat, a main tubular heat conducting member depending from the lower end of the tubular member toward but not to the upper end of said member and separating it from said auxiliary heat conducting member, whereby when oil is fed to the space between said main member and tube at a rate in excess of capacity of said main member to vaporize it, it overflows into said tube and is vaporized by the auxiliary heat conducting member.

' 15. In an oil burner, a burner base, a housing connected to said base and deriving heat therefrom to vaporize fuel, said housing affording within it two chambers located one inside the other and communicating only at their upper ends, means for supplying oil to the outer of said chambers to be vaporized by the heat of said housing, an outlet for vapor overlying the inner of said chambers, and an auxiliary heat conducti'ng member connected to said base and extending into said inner chamber, whereby when oil is vaporized in the outer chamber at a rate less 'than that at which it is supplied thereto it will overflow into the inner chamber and be vaporized by said auxiliary member. j 16. An oil burner, comprising, a base having a plurality of endless fuel channels disposed one within the other in air-spaced relation, pairs of foraminous walls one pair for each said channel extending from opposite sides thereof and forming therebetween combustion chambers, means operable continuously to supply fuel to one of said channels to maintain in the combustion .chamber associated therewith a fire sufficient to maintain said base at vaporizing heat, a'tubular heat conducting member depending from said base, said member having its lower end closed and having an outlet for vapor in its upper end and being otherwise closed, a conduit connecting said outlet to the other of said channels to supply vaporized fuel thereto, a tube extending from the lower end of said member upwardly within the same in spaced concentrical relation and terminat-ing short of the upper end of said member forming within the latter inner and outer fuel chambers communicating only at their upper ends, and meansto supply oil to be vaporized to one of said fuel chambers, said outlet for vapor having direct communication with the other fuel chamber only.

17. An oil burner, comprising, a base having a plurality of endless fuel channels disposed one one of said channels to maintain in the combustion chamber associated therewith a fire sufficient to maintain said base at vaporizing heat, a main tubular heat conducting member depending from said base, said member having its lower end closed and having an outlet for vapor in its upper end and *being otherwise closed, a conduit connecting said outlet to the other of said channels to supply vaporized fuel thereto, a tube extending from the lower end of said member upwardly within the same in spaced concentrical relation and terminating short of the upper end of said member forming within the latter inner and outer fuel chambers communicating'only at their upper ends, means to supply oil to be vaporized to one of said fuel chambers, said outlet for vapor having direct communication with the other fuel chamber only, and an auxiliary heat conductor depending from said base and extending a substantial distance into the inner fuel chamber.

DONALD C. ELLIOT. WARREN H. DE LANCEY.