US1753360A - Liquid-fuel burner - Google Patents

Description

pr 8, E9 J. M. BROWN LIQUID FUEL BURNER Filed Aprvil 9, 1928l 4 Sheets-Sheet l l lll llllllllllh n mum April E930. J. M. BROWN LIQUID FUEL BURNER Filed April 9, 1928 4 Sheets-Sheet 2 vwemboz WITNESS Qwj/fm April 8, i930. J. M. BRowN j@ LIQUID FUEL BURNER Filed April 9. 1928 4 Sheets-Sheet 3 APIii 8 E93om J. M. BROWN l,753,360

LIQUID FUEL BURNER `Filed April 9, 1928 4 Sheets-Sheet 4 75 l 7? Snom/16oz fav W Ma @W WITNESS atto/014mg y Patented Apr.. 8, 1930- l UNITED vS'II'QLTES, PATENT OFFICE JOHN MURTON BROWN, OF IRVINGTON, NEW JERSEY, ASSIGNOR T0 CRYSTAL OIL BURNER CORPORATION, OF IRYINGTON, NEW JERSEY, A CORPORATION OF NEW JERSEY LIQUID-FUEL BURNER Application tiled April 9,

My present invention relates to liquid fuel burners and more particularly to a liquld fuel burner capable of use in domest1c or household heating systems.

For the complete and perfect combustion of liquid fuels, the lideal conditions are to have the fuel in a completely gasiied phase and thoroughly mixed with suilicient airfor its complete combustion or, with sullicient primary air for the required initial combus tion. Under these conditions the combustion is uniformly and rapidly accomplished throughout the air and fuel mixture and there is no opportunity for a part of the fuel to receive an inadequate amount of air or to be carried through the furnace Without being burned. The combustion of liquid fuel in a furnace of small dimensions, such as used for household heating, presents obstacles to the attainment of these ideal conditions,

articularly when the fuel isv a heavy distilate fuel oil. Thus, if the oil be sprayed or atomized directly in the furnace or be otherwise introduced into the furnace in li uid condition, the vaporizing of the fuel an 1ts complete and thorough mixing with suficient A air for combustion must be accomplished in `the narrow connes of the furnace prior to ignition and combustion and without contact with the relatively cool surfaces of the boiler or heat absorbing elements.

Inasmuch as the vaporization of the oil requires a considerable amount of heat which must be absorbed from the llame, thislvaporization requires time and acts to. check the combustion by cooling the portions of the flame near the fuel particles. Upon being vaporized or gasied, the liquid fuel must be disseminated through or mixed with the air for combustion before it can be burned. In the event that the fuel passes into the llame before it is completely vaporized and mixed with the air, it may be incompletely burned, or even cracked to carbon which floats in the combustion gases in the form of fine particles of soot.

Vaporization of the fuel in a separate apparatus outside 'of the furnace, and prior to its mixin with the air, for combustion, is dillicult an impractical in domestic fuel 1928. Serial No. 268,429.

burning apparatus because of the danger involved in the vaporization at high temperatures and the ditliculty of controlling the vaporization so as to obtain a steady and uniform supply of the vaporized or gaseous fuel proportionate to the air supply.

An object of my invention is to provide a method and an apparatus whereby a liquid fuel is brought to a gaseous phase and thoroughly mixed with alr for combustion prior to its release within the combustion zone of a furnace.

Another object of the invention is to provide an apparatus for burning fuel in which all danger of carrying an unvaporized liquid fuel into or through the combustion zone of a furnace is avoided. Further objects of the invention are to provide a liquid fuel burner in which the fuel and air for combust-ion are mixed in proper proportions and are 'brought toa homogeneous mixture upon entering the furnace; to provide a fuel burning apparatus in which the liquid fuel is vaporized and transformed into a gaseous phase under conditions requiring a minimum of temperature; to provide apparatus in which the separation of the fuel from the air with which it is mixed is prevented; to provide a safety means whereby, upon the failure of the ignition or of the igniting means, the vaporized fuel is separated from the air and a further supply of fuel is shut off to provide a suitable and effective carburetting means for heavy distillates or fuels suitable for combustion in domesticheating furnaces and whereby the supply of fuel and air may be correctly and accurately proportioned; to provide an improved fuel supply and pumping means; and to provide an improved pilot light and igniting means for a furnace of the above indicated type.

With these and other objects in view which will be more clearly apparent from the following description, the invention comprises the fuel burning method and apparatus described and set forth in the following specification and claims.

The various features of the invention are illustrated in the accompanying drawings, in which: l

Fig. 1 showsa furnace, partly broken away, and a fuel burning apparatus embodying a preferred form of the invention installed in position in the furnace.

Fig. 2 is a vertical sectional View through that part of the fuel burner apparatus in which the fuel is mixed with air prior to its entry into the furnace.

Fig. 3 is a vertical sectional view taken on line 3-3 of a fuel feeding element of the burner shown in Fig. 1.

Fig. 4 is a detail sectional view taken on line 4:-4 of Fig.

Fig. 5 is a vertical sectional view of the carburetter apparatus taken on the line 5-5 of Fig. 2.

Fig. 6 is a detail sectional view of a safety or stopping apparatusl for closing the fuel and air supply uponfailure of the pilot light or ignition devices.

Fig. 7 is a side view of a portion of the automatic apparatus.

Fig. 8 is a sectional elevation of the safety apparatus taken on line 8 8 of Fig. 7.

Fig. 9 is a plan view of a burner, the re tort or super-heater element being removed.

Fig. 10 is a vertical sectional View of the burner and super-heater taken on line 10- 10 of Fig. 9.

Fig. 11 is a detail sectional View of a part of the burner. v

In my present invention a continuous supply of liquid fuel is fed to a carburetting element into which is also drawn a continuous supply of air. In the carburetting element the liquid fuel is broken up into fine particles which are disseminated throughout the air stream to form a fine mist or suspension. The air and suspended fuelare so proportioned as to provide adequate primary air or oxygen for the commercial combustion of the fuel. The mist of air and suspended fuel is then forced by a pump through a direct passage to a retort or super-heating element located directly in the fire box of the furnace. This super-heating element is heated by the flames in the furnace and the mist' of suspended air is caused to pass through the super-heating element in such a manner as to subject the air and the suspended fuel to the heat of the retort until the liquid fuel is completely gasified and is super-heated to a greater or less degree above that point at which it would tend to condense. During this gasifying or super-heating the liquid fuel is still more thoroughly mixed with the air for combustion, forming a uniform, homegeneous, gaseous mixture which has been slightly preheated by the heat of the fire box. The mixture of gasified fuel and air then passes into the distributing chamberof the burner and y thence through burner outlets into the lire box of the furnace, whereupon it is immediately ignited and burns freely, mixing with additional air for complete combustion. The

burner is provided with a pilot light so that should the supply of fuel and-air be shut off by the usual thermostatic means, and again turned on, the fuel will he ignited upon passing through the burner outlets, immediately reheating the retort or super-heating chamber and providing for the subsequent gasification of the fuel. In the event that the pilot light should be blown out or fail from any cause, the super-heater will become cold and will then act as a baffling device for separating the fuel from the air. 'lhe separated fuel then passes to an automatic shut off device which serves to cut ofi' further supply of fuel and air.

Referring more particularly to the accompanying drawings, a supply of liquid fuel is drawn from any suitable storage reservoir, not shown, through a supply pipe 15, Fig. 3, and a shut-off valve 16, and an inlet pipe 17 to a rotary pump 18. The pumping chamber 19 of the pump 18 is formed by providing a cylindrical recess in one end of a casing 20, the end of which recess is closed by a cover plate 21. Within the cylindrical recess 19 a cylindrical rotor 2 is eccentrically mounted on a rotating shaft 23 supported at one end in a bearing 24 in the cover of the plate 21 and extending through a bearing 25 in the casing 20, and through a packing gland 26. The shaft 23 is driven by means of a motor 27 which also serves to supply air for the combustion of the fuel. The eccentric mounting of the rotor 22 on the shaft 23 brings one portion of the cylindrical surface of the rotor in close contact with the inner cylindrical surface of the recess 19 and provides a narrow, curving space between the opposite faces of the rotor and recess. As the rotor rotates in the cylindrical recess this space also rotates. Between the inlet pipe 17 and outlet pipe 28 of the rotary pump there is positioned a radial sliding partition 29 which is biased or pressed against the rotating surface of the rot-or by means of a spring 30, the pressure of which isregulated by means of a screw 31.

As the rotor rotates in the direction shown by the arrow in Fig. 3, the space beyond the sliding partition in communication with the inlet 17 increases and draws oil through the pipe 17 to fill this space. As the contacting part of the rotor passes the partition29, it forces the liquid outwardlythrough the out-- let pipe 28. The rapid rotation of the rotor thus provides a smooth and continuous supply of oil under pressure to the pipe 28. From the pipe 28 a portion of the oil passes upwardly to a vertical pipe 32 and through a regulating valve 34 and return pipe 35 back to the supply reservoir. The remainder of the liquid fuel passes throughA a branch pipe 36 through an automatic solenoid valve 37 and pipe 38 to a float chamber 39 of the carburetter apparatus which is shown in detail zontal per orate aveaeec inl-Figs. 2 andf5. A constant level ofthe-- liquid is maintained in the yfloat chamber .39 by means ofa oat valve 40 which controls the inlet to the chamber inaccordance with the level" of' the oil 'and causes'a proportionate quantity to return through the valve 34 to the" supply tank. From the oat chamber 39 the oil passes through a passageway 41 and past an ad'ustin needle valve 42 to a horiatomizin pipe 43 which rojects into a mixing cham er 44 of the carburetter. The atomizing pipe 43 is provided with spaced perforations 45 in its upper surface through which the liquid fuel may pass into contact with a current of air flowing through the mixing chamber 44 and may thereb be torn loose from the openings and carrie in suspension by t-he passing air. A blast of air is drawn into the mixing chamber 44 throu l1 openings 46 in the lower part of an outer aille shell 47, openings 48 in the upper part of an inner baie shell 49 and openings 50 in a part of the mixing chamber 44 which extends into the inner shell 49. The passage of the air from the inlet openings 50 through the mixing chamber is controlled by an adjustable baille plate 51 supported on a horizontal pivot 52 at the upper part of the chamber, Ithe angle or position of the baffle 51 being controlled by an adjusting screw 53 which bears against an arm 54 rigidly mounted on the outer end of a supporting shaft 52. It will be understood that the quantity of air may be increased by tilting the baille plate 51 upwardly, or decreased by tilting the baffle plate 51 downwardly towards vertical position to increase the resistance to the flow of air. After passing the baie plate 51, the air is deflected upwardly towards the horizontal atomizing pipe 43 by means of an inclined baiiie plate 55 which extends from the lower wall of the chamber 44 towards the lower edge of the atomizing pipe 43. The air is then deflected over the 0penings 45 in the pipe 43 and, by its rapid passage, continuously tears away the upper part of the oil and carries it in finely divided form through the chamber 44.

With a given adjustment of the oat chamber 40 and the needle valve 42 to provide a definite supply of liquid fuel through the openings 45, the relative proportions of liquid fuel and air are constantly maintained regardless of the velocity or volume of fuel and air. Should any of the suspended fuel settle out of the carrying air, particularly upon a temporary shutting down of the burner, it will be received in a sump or collecting recess 56 formed in the lower part of the chamber 44.

The` quantity of liquid fuel accumulated in the sump 56 is limited by means of an overflow pipe 57 which projects a short distance above the bottom of the sum 56 and permits an excess of oil to overflow into a collecting pan- 58, from'which it returns, by means-cfa u pipe 59, .tothe supply tank or'A other re receptacle.

vUpon again starting up the burner, a por tion of theair that passes beneath the damper 51 is by-passed through an opening 60 in the bale plate 55, down. into contactv with the surface ofthe liquid fuel collected in the sump '56, and thus this liquid is carried by this by-pass current of air into the main draft of air passing through the chamber 44.

The velocity of the air through the chamber 44 is controlled by means of a damper 61 mounted on a rock shaft 62 projecting through a wall of the chamber 44, and having a weighted crank arm 63 that may be con- Xtrolled by a thermostatic element, or otherwise. The upward swing of the damper 61 is limited by means of a set screw 64 projecting downwardly from the .upper wall of the chamber 44, and the downward swing of the damper 61 is limited by means of a set screw 65 on the outer wall of the chamber 44 in the path of an extension of the arm 63.

The draft of air is drawninto and through the chamber 44 by means of a fan or blower 66 in a fan casing or chamber 67 having an axial inlet directly connected to the outlet of the chamber 44. The fan 66 is mounted on a shaft 68 which is connected directly to, and rotated by, the shaft of the motor 27. By the rotation of the fan 66 the air is drawn centrally into the casing 67 and is thrown radially outward by the centrifugal action of the fan. The mixture of air and fuel Iis thus put under pressure by the action of the fan and passes through a pipe 69 to a retort or super-heater 7 O mounted within a furnace 7l.

It is necessary to the safety of the apparatus and to convenience in operation that the mixing chamber 40 and its associated elements be placed at a short distance from the furnace 7l. The outlet of the fan casing 67 is brought to such a position that it is in a direct line with the inlet to theretort 70. The connecting pipe 69 is, therefore, a straight,

direct connection from the fan 67 to the retort, thus avoiding any changes in direction of flow which would tend to throw the suspended particles out of suspension in their passage from the fan to the retort. Should any considerable number of particles collect on the walls of the pipe 69 by a chance impingement, they would be graduallyblown.

tort or super-heater the liquid fuel is trans formedv completely to the gaseous phase and mixes uniformly and homogeneously as a gas with the air. For this purpose it is not necessary to crack the molecules to a permanent gas that will not subsequently condense, but it is only necessary to heat and maintain the fuel at a temperature above that at which it will vaporize or gasify into the carrying air, which temperature is below the normal boiling temperature of the liquid fuel. Thus, the air serves not only its normal purpose for the later combustion of the fuel, but also to facilitate and promote the ready gasification of the fuel.

A slight cracking of the liquid fuel may occur and is not objectionable so long as it docs not deposit an appreciable amount of carbon in the super-heater or does not involve the preheating ofthe air and gas mixture to a dangerous temperature.

As the air is delivered to the retort 70 from the pipe 69 it is received in van inlet chamber 7 3 formed between the vertical, cylindrical walls of the retort 70 and a vertical out-let pipe 74 that projects upwardly into the retort to a level above that of the pipe G9. The air received in the chamber 73 is prevented from by-passing directly upwardly into the pipe 74 and is constrained to pass downwardly and about the pipe by means of a horizontal partition 75 immediately above the mouth of the pipe 69 and extending from the wall of the retort 70 to the yupper edge of the outlet pipe 74 throughout a considerable arc of the adjacent edge of the outlet pipe. The outer edges of the partition 75 are extended downwardly to provide a vertical partition 76 which may extend downwardly to any desired distance. depending upon the particular proportioning of the passages in the retort. As the mixture of air and suspended fuel particles pass under the lower edge of the vertical partition 76, they pass to the opposite side of the retort, thence upwardly and over the edge of the outlet pipe 74 and then downwardly to the burner 7 2. The outlet pipe 74 of the retort 70 delivers the gaseous' air and fuel mixture from the retort through a central openin g 77 to a burner chamber 78 of the burner 72. From the burner 78 the gaseous mixture of air and fuel is distributed to a number of burner outlets or ports 79 arranged in four concentric circles about the pipe 77.

Upon passing from the burner ports or outlets 79 the mixture of air and gasified fuel is ignited and burned in the space surrounding r the retort 70, thereby serving to heat the retort 70 and the air and fuel passing therethrough. The most intense heat will, of course be imparted to the lower part of the retort 10 which is most directly exposed to the f, heat of the flames. In the event that any of the liquid fuel particles entering the retort 70 should be separated out of the carrying air by the bailiing effect of the inner outlet pipe 74 and the partitions 75 and 76, and the consequent changes in direction occasioned therein the recess 80 is immediately vaporized because of its exposure to the highest temperature in the retort and thus supplies an initial quantity of gasitied fuel after the ignition of the liquid fuel about the retort.

The burner 72 is provided with a vertical iange 81 encircling the burner outlets or ports ,79 and serving to shield the burner ports from a direct inrush of air. This shield is particularly useful and desirable upon the starting up of the burner or upon the intermittent stopping and start-ing of the burner in accordance with a control device. For this starting and stopping of the burner, a pair of pilot burners 82 and 83 are supplied with gas from a pipe 84 and branch pipes 85 and 86, the ends of which are arranged in suitable notches in the flange 81 to deliver gas flame to the space immediately within the flange 81. It will be understood that the pilot burners 82 and83 are always supplied with gas in the usual manner.

The action of the retort burner and pilot lights upon starting from a cold condition is as follows: As the air, with its suspended liquid fuel particles, enters the retort 70 from the pipe 69, a considerable, if not a large portion of the liquid particles, upon striking the outlet pipe 74 and baffles 75 and 76, are caught and separated from the passing current of.

air. These particles then collect in the trough 80 until they reach the level of a small diameter overflow tube 87 which projects into the trough to a level slightly above the bottom of the recess 80. The separated liquid fuel overiiows downwardly through the tube 87 to a recess formed in the burner Within the vertical encircling ange 81. The liquid fuel dropping from the tube 87 is received on a c1rcular asbestos wick 88 extending about the burner within the lower part of the flange 81 and in the directpath of the flame of the pilot lights 82 and 83. The liquid fuel thus received on the wick is locally vaporized and 1gn1ted by the pilot flame, thus additionally heating the tube 87 and the retort 70. The portion of the liquid fuel particles not separated out within the retort 70 are carried by the current of air into the burner chamber 78 and outwardly through the opening 79, and also into contact with the pilot lights, and mixing with the fuel vaporized from the wick 88, increase the llame about the retort 7 0. The retort 70 is thus rapidly heated, providing a progressively better gasiied fuel and soon reachin a point at which a completely gasiied fuel 1s delivered to the ports r9 and a blue fiame formed about the retort 70.

Therecess 89 in which the wick 88 is positioned lwithin the vertical flange 81, as shown in detail in Fig. 11, is progressively deepened from one end to an end delivering to an outlet or overflow pipe 90., The purpose of this gradual deepening of the fuel recess is to cause theliquid fuel to fiow uniformly throughout the wick and prevent it from collecting in spots.

To facilitate the distribution of the vapors that are evolved from the wick 88v so as to obtain a complete and uniform ignition, the

' bores of the outer ring of burner ports or outlets 79 are inclined slightly outwardly and circumferentially so as to give a circulatory movement to the issuing Jets about and over the wick 88. The bores of the ports of the outer ring are also made smaller than those of the inner ring to avoid creating too strong a draft at the pilot lights and to thus minimize the danger of blowing out and ex- A tinguishing the pilot lights. This tends to cause the fuel vapors to move in a circular fashion past the pilot burners 82 and 83 and over the wick so as to carry the flame around the burner.

The bores of the inner burner ports incline upwardly and outwardly so as to cause the fuel and air jets to intersect those of the outer ring of ports and to strike an outer, annular dished plate 91, the lower inner edge of which rests on the upper edge of the lvertical flange 81 and which is held in place by a downwardly projecting flange 92,v which fits around the outer, upper surface of the vertical flange 81. The annular plate 91, which may be made in two parts so that it may be easily placed on the vertical flange 81, becomes heated to incandescence and thus promotes a uniform combustion of the fuel and provides a surface for the radiation of heat. The plate 91 also prevents the inrush of cold air about and over the burner ports and thus prevents the flame from being extinguished at the starting of the apparatus, and also serves to throw the ame from the burner l outwardly and to distribute it throughout the fire box of the furnace.

In the event that the pilot lights lbecome extinguished and that upon the stopping and re-starting of the burner the fan 66 and pump 18 should continue to supply air and fuel through the pipe 69 to the retort 70, the par-l ticles of suspended fuel will be separated very largely in the retort 70 by the baille plates and 76 and the overflow pipe 74. The fuel thus separated from the air collects in the recess until it reaches the level of the upper end of the pipe 87, whereupon it overflows through the pipe V87 into the recess 89. Residual fuel that may be carried downwardly into the outlet pipe 74. and thence into the burner chamber 78 will be largely separated therein and in passing through the small burner port 79. The fuel thus separated in the retort 7 0 and in the burner 72 continues to accumulate in the trough 89 until it reaches the level of the overflow pipe 90. To prevent any of this collected fuel from flowing back into the chamber 78 through the burner ports 79, the outer ends of each of the burner ports 79 open through raised nubs or mounds 93. From the overflow pipe 90 the oil flows through a connecting pipe 94 to a horizontal pipe 95, one end of which is closed and is rigidly supported on a. vertical standard 96, which also serves to support a casing 97 for the motor 27. The pipe is provided with a small outlet 98 through which the oil escapes. A collecting box 99 is pivotally mounted on the pipe 95 to collect the fuel that drops through the outlet orifice 98. The

lli

weight of the box 99 and its contents is bal- 99 to tilt on thepipe 95 may be adjusted by making the weight 100 slidable on the supporting rod 101 and fixing it in position thereon by means of a set screw 102.

It will be understood that whenever the pilot lights l82 and 83 become extinguished and fuel and air are supplied through the pipe 69, the fuel separated in the retort 70 will pass through the pipe 87, the overflow pipe 90 and the above connections to the collecting box 99, and that the fuel thus collecting in the box 99 will, in a short time, be sufficient to cause the box to tilt on the pipe 95. The downward tilting movement of the box 99 is transmitted through a rod 103 to an arm 104 of a switch 105 which controls the supply of electric current to the motor 27. This switch may be of any suitable type, a quick acting spring switch being shown by way of example. A wire 106 from the supply of current leads directly to the motor 27 and a return wire 107 leads from the motor to a binding screw 108 of the switch 105. A'return wire 109 is connected to a binding screw at the other end of the switch 105. From the wire 106, a branch wire 110 leads to the solenoid valve 37 and a return wire 111 leads from the solenoid valve to the binding screw 108 of the switch 105. It will be apparent that when the rod 103 is lowered, the switch is opened, thereby breaking the circuit both to the motor and to the solenoid valve, positively cutting off the supply of fuel and stopping the fan 66 and the pum 18.

It will be apparent that t e elements of the burner may be assembled in various arrangements. In the Bpreferred form, as shown particularly in igs. 1 and 2, the air and fuel supplying elements, and the various controls therefor, are mounted and supported on the vertical standard 96 which directly supports the motor casing 97. At 011e end of the motor casing 97 there is mounted, by means of screws112, a projecting arm 113 in alignment with, and enclosing, the motor shaft 23. The casing of the pump 18 is cast integrally with the outer end of the arm 113, the pump and the motor being thus united in one unitary assembly. At the opposite end of the motor casing 97 is integrally cast one' vertical face of the peripheral wall of the fan easing 67. A housing 114 for the switch 105 is also cast on the motor casing 97. The outer vertical plate 115 of the fan casing 67 is bolted or screwed directly to the casing of the chamber 44 which is, in turn, bolted to the plate 115.

The arm 113 isso positioned that any oil leakinof from the gland or stuffing box 26, or from tzlie bearing 116, is collected therein and flows through a drain pipe 117 into the sump 56 of the mixing chamber 44. Similarly, the oil overflowing from the other bearing 118 of the motor 27 passes through ,channels 119 in the bearing blo`ck 120 to a drain pipe 121, and thence to a conduit 122 and outlet pipe 123 which leads to the pan 58. In this way all leakage of oil from the apparatus is avoided.

The burner apparatus may be mounted in any of the usual types of furnaces by supporting the burner 72 on brick work 124 placed on the furnace grates, which are covered with a layer of asbestos or fire brick.

The height of the burner 72 is so selected that the pipe 69 may enter through an opening cut in the ordinary fuel door 125. To enable the fuel and air supply elements to be brought to a height corresponding to that of the retort 70 and burner 72, the standard 96 is made vertically adjustable in a supporting base 126 an?. held in posit-ion by means of set screws 12 In the operation of 'the above described burner, a combustible mixture of fuel and air is formed in the chamber 44 and conveyed through the pump casing 67 and pipe 69 to the retort 70. The mixture is not readily combustible in the condition in which. vit passes through the pipe 69, inasmuch as the oil is in liquid form and thus has a quenching action on combust-ion. As the pipe 69 enters the furnace, the portion immediately above the burner 72 passes through an intensely heated flame which'might vapo'rize and serve to ignite the fuel and air mixture. To avoid too great concentration of heat at this point, the lower part of the pipe 69 may be shielded by means o f a semi-cylindrical iron projecting shield 128. Although the retort 70 is subjected to the flame, the fuel is in rapid and turbulent circulation through the retort which causes the heat to be rapidly absorbed and disseminated throughout the air and fuel mixture, and to be absorbed by .condition favorable to immediate combustion upon their escape from the burner ports. Sufficient pressure is created in the pi e 69 to the retort 70 and burner chamber 8 by the fan 66, to ensure a velocity through the burner port 78 sufficient-ly high to prevent a back firing of the flame into the chamber 78 and retort 70.

As changes of construction could be made within the scope of my invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. Combustion apparatus of the type described which comprises a burner having upwardly and outwardly directed burner ports arranged about a central axis and a retort mounted centrally above said burner, said retort having a. central outlet pipe projecting from said burner upwardly into said retort, an inlet in a vertical wall of said retort, and a partition extending from said vertical wall above said inlet to said outlet pipe.

2. Combustion apparatus of the type described which comprises a burner chamber having a central inlet and having outlet ports arranged about said inlet, a retort above and connected to said inlet, an upwardly projecting annular flange at the outer edge of said burner chamber, a channel extending between said flange and said burner chamber, and an overflow outlet from said channel, said channel being of increasing depth to said overfiow outlet, gas pilot jets projecting inwardly over said channel, the outer of said burner ports being of smaller bore than the inner ports and directed outwardly and circularly about said burner-chamber.

3. Combustion apparatus" of the type described which comprises a burner chamber having a central inlet and burner ports arranged' about said inlet, a retort above and connected to said inlet, said retort having a pocket at its lower portion, an upwardly projecting annular flange at the outer edge of said burner chamber, a channel positioned at the outer edge of said burner chamber within said flange and having an overow outlet, said channel being of increasing depth to said overflow outlet, gas pilot jets projecting inwardly and above said channel, a wick in said channel, and a pilot pipe extending from scribed which comprises .a burner c said retort'above said pocket to a short distance abovesaid wick.

4. Combustion apparatus of the tylpe deamber having a central inlet in its upper face, upwardly and outwardly projecting burner ports arranged about said inlet, a retort positioned centrally above said chamber and delivering to said inlet, an upwardly projecting annular fiange at the outer edge o said burner chamber, and an annular dished plate restino* on the upper edge of said flange and exten ing upwardly and outwardly therefrom.

5. Apparatus of the type described which comprises a burner, a super-heating retort for said burner, a carburetter, a fan for draw-l ing air through said carburetter and supplying carburetted air to said retort, a pump for supplying liquid fuehto said carburetter, an'electric motor for driving said fan and pump, batlie lneans in said retort to remove unvaporized liquid from the air current passing therethrough, and means actuated by the accumulation of unvaporized oil from said p retort to stop said motor.

6. Apparatus of the type described which comprises a burner, a super-heating retort for said burner,a carburetter, a fan for drawing air through said carburetter and supplying carburetted air to said retort, a pump for supplying liquid fuel to said carburetter,

an electrlc motor for driving said fan and said pump, a fuel control valve, baille means in said retort to remove unvaporized liquid from the air current passing therethrough, and means actuated by the accumulation of unvaporized oil from said retort to stop said motor.

7. Apparatus of the type described which comprises a burner, a super-heating retort for said burner, a carburetter, a fan for drawing air through said carburetter and supplying carburetted air to said retort, a pump for supplying liquid fuel to said carbure'tter, an electric motor for driving said fan and pumpbaiiie means in said retort lo remove the unvaporized liquid from the air current passing therethrough, a tiltable collecting pan receiving separated oil from said retort, and an electric switch for said motor-actuated by said tiltable pan upon the accumulation of a predetermined amount of liquid therein.

8. Apparatus of the type described which comprises a burner, a super-heating retort for said burner., a carburetter, a fan for drawing air through said carburetter and supplying carburetted air to said retort, an electric air when cold, and a recess for collecting said a super-heating retort separated fuel particles, and means for re- 'ceiving separated liquid fuel from said Vrecess and acting upon the acculnulation of a predetermined quantity of said liquid fuel to stop the supply of said air and suspended fuel particles. ,y v

10. Liquid -fuel burning lapparatus which comprises a burner, a super-heating retort connected to said burner, an air and liquid fuel mixing chamber, a fan for drawing air through said mixing chamber and driving said air without substantial change in direction to said retort, a horizontal perforated fuel supply pipe in said mixing chamber, a delecting plate for delccting air towards said horizontal pipe, a regulating damper, means to adjust said damper to set positions to vary the resistance to the flow of said air tol said horizontal pipe, and a control damper movable within set limits to control the flow of air through said mixing chamber.

11. Liquid fuel burning apparatus which comprises a burner, a super-heating retort connected to said burner, an airand liquid fuel mixing chamber, a fan for drawing air through said mixing chamber and supplying said air in a direct path to Said retort, a horizontal perforated fuel supply pipe in said mixing chamber, a delecting plate for delecting air towards said horizontal pipe, a collecting sump in the lower part of said chamber, an opening in the lower part of said deflecting plate for admitting air to said sump, and a damper to control the flow of air through said mixing chamber.

12. Liquid fuel burning apparatus which comprises a burner, a super-heating retort for said burner, an air and fuel mixing chamber, a fan for drawing air through said mixing chamber and supplying said air to said retort, a motor for driving said' fan, a horizontal perforated fuel supply pipe in said mixing chamber, a collecting sump in the lower part of said mixing chamber, motor control means actuated by the accumulation of liquid to stop said fan, and an overiow pipe from said collecting sump to said motor control means.

13. Liquid fuel burning apparatus which comprises a burner, a super-heating retort for said burner, an air and liquid fuel mixin chamber, a fan for drawing air through sai mixing chamber and supplying it to said retort, a pump for supplying fuel to said mixing chamber, a motor for driving said pum and said fan, a by-pass for the oil delivereil from said pump, and a regulating valve to control the amount of oil delivered to said mixin chamber.v

14. iquid fuel burning apparatus which .pump

comprises a burner, a su er-heating retort mounted on and connected) to said burner, a mixing chamber for liquid fuel and air, a

for supplying fuel to said mixn chamber, a fan for drawing air through sai `mixing chamber and forcing said air to said retort, a motor for driving said pump and said fan, means forsupportng said mixing chamber, motor, pump and fan in a unitary structure, means for adjusting the vertical height of said sup orting mea-ns, and av straight pipe connectlon from said fan to said l retort.

15. Apparatus of the type described which comprises a burner, a super-heating retort mounted thereon, a horizontal inlet pipe for saidretort, a supporting standard, a motor mounted on said standard at an adjustable hei ht, a blower supported and driven by sai motor and delivering to said inlet pipe, an air and fuel mixing chamber connected to the inlet of said blower, a rotary pump supported and driven by said motor, by-pass means for delivering a part of the liquid from said pump to said mixing chamber, a cut-olf means supported by said standard for stopping said motor and closing said by-pass fuel feeding means upon the accumulation in said cut-off means of a predetermined quantity of liquid, bale means in said retort providing a collecting pocket therein, and overflow means from said pocket leading to said cut-oftl means.

' 16. Apparatus of the type described which comprises a burner chamber having an upper plate provided with an inlet opening and a number of surrounding burner ports, a vertical annular flange surrounding said burner plate, a circular channel between said annular flange and said burner plate gradually increasing in depth from a point about said burner plate to an adjacent point, an asbestos wick in said channel, an overflow opening at the dee est end of said channel, a retort mounted) on the upper plate of said burner and having a vertical delivery pipe projecting upwardly in said retort, and an overow duct extending from a level slightly above the bottom of said annular channel to a posi- 59 tion above said asbestos wick.

In testimony whereof I aiiix my signature.

JOHN MURTON BROWN.

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