US3348598A - Burner and its operation - Google Patents

Description

Oct. 24, 1967 Filed March 8, 1965 5 Sheets-Sheet 1 INVENTORS MILAN MOMCHILOVICH ATTORNEY WALLACE F. RHODES a Oct. 24, 1967. M. MOMCHILOVICH ET AL 3,348,598

BURNER AND ITS OPERATION 5 Sheets-Sheet 2 Filed March a, 1965 INVENTORS' WALLACE F. RHODES a MILAN MOMCHILOVICH FIG. 5

ATTORNEY 1967 M. MOMCHILOVICH ET AL BURNER AND ITS OPERATION 5 Sheets-Sheet 3 INVENTORS WALLACE F. RHODES a v MILAN MOMCHILOVICH BY Filed March 8, 1965 ATTORNEY Oct. 24, 1967 M. MOMCHILOVICH ET AL BURNER AND ITS OPERATION 5 Sheets- SheeT; 4.

Filed March 8, 1965 WALLACE F RHODES a MILAN MOMCHILOVIC BY INVENTORS A T T ORNE Y Oct. 24, 1967 MOMCHILOVICH ET AL 3,348,598

BURNER AND ITS OPERATION Filed March 8, 1965 5 Sheets-Sheet s Q) LL INVENTORS LL WALLACE F. RHODES a MILAN MOMCHILOVICH BY ATTORNEY United States Patent 3,348,598 BURNER AND ITS OPERATION Milan Momchilovich, Akron, and Wallace F. Rhodes,

Stow, Ohio, assignors to The Falls Stamping and Weld- Filed Mar. 8, 1965, Ser. No. 437,702 Claims. (Cl. 1584) This application is a continuation-in-part of our Ser. No. 236,481 filed Nov. 9, 1962 now abandoned.

This invention relates to an oil burner which includes a new nozzle and new combustion chamber, etc. which include novel features of constiuction. The invention relates also to a new method of oil combustion.

The burner is designed particularly for use in operations in which the burner is turned all of the way ON. Provisions are made for varying the oil and air supplied, between a higher or lower heat requirement. At the time the burner is manfactured or when it is installed, the proper means is selected for feeding just the required amount of oil and air through the nozzle, and this amount will be greater or less depending upon the firing rate, i.e. the B.t.u. (British thermal unit) rating of the equipment in which the burner is installed.

The burner is particularly adapted for use in a dwelling, such as a home or apartment, in which one or more furnaces, water heaters, incinerators, clothes driers, etc. are installed. Each is provided with a burner, and all of the burners are supplied with oil from a single source. For this purpose, a small reservoir for oil, equipped with a constant-level device, is provided just below each burner nozzle, and oil is lifted from this constant-level device up into the burner by air supplied from a single compressor provided with a manifold which feeds air to each burner through a different outlet under a given pressure.

Each burner functions only when air is supplied to it. The air draws the oil into the burner. The air supply for any one burner is always under the same pressure, although the air may be supplied from the manifold to the ing Company, Cuyahoga Falls, Ohio, a corporation of 0 different burners under different pressures. On installation,

the oil burner is equipped to supply the amount of oil required for that burner, and a larger or smaller number of openings are provided in the burner for admission 'of the equired amount of secondary air for combustion of that amount of oil. The amount of oil'supplied to a burner depends upon the firing rate of the equipment in which it is installed. I

Pressure valveson the air manifold supply air through separate air lines to the different pieces of equipment at the required pressures which may be different in each air line. For instance, identical burners, with proper adjustment at the time of installation, may provide air at 3 pounds pressure per square inch to the burner in an incinerator which uses 18 cubic centimeters of oil per minute to provide 35,000 B.t.u. (British thermal units) to the incinerator, and air at 4 pounds pressure per square inch to the burner in a furnace which uses 38 cubic centimeters of oil per minute to provide 75,000 Btu. to the furnace. The system is designed particularly for operation at low air pressures, usually less than ten pounds per square inch,

although a higher air pressure may be used. The burner may be used in a commercial installation, but is designed particularly for use in a system in a dwelling, which may be a modification of the system described in US. Ser. No. 236,481 filed Nov. 9, 1962, by Momchilovich and Rhodes.

Oil and primary air are supplied to the burner nozzle. A whirling motion is imparted to this mixture within the nozzle. After leaving the nozzle, secondary air is added to the mixture, it is given a whirling motion, and passed over heated wires (preferably a stainless steel of high 3,348,598 Patented Oct. 24, 1967 quality) and usually arranged as a series of screens, to gasify the oil. The Wires are heated to red or while heat, i.e. about 1800 F. or greater. They break down any droplets in the air-oil mixture and radiate infra-red rays which quickly heat the mixture passing between the wires to a temperature at which the oil is broken down and gasified. The resulting gaseous mixture is supplied to a supplement tal burner where it is burned. This supplemental burner may be of any suitable construction.

It is desirable to provide a series of wires or screens in the combustion chamber, and the oil and air may pass through these in only one direction; 'but it is preferable to mix secondary air with the mixture after it has passed through the wires or screens in one direction, and then pass the mixture back through the Wires or screens and there blend the gasified product with the gases in the combustion chamber and pass this from there to'the supplemental burner where complete combustion takes, place.

No soot deposits form within the nozzle or combustion chamber, due primarily to the temperatures involved.

' The invention is further described in connection with the accompanying drawings, in which:

FIGURE 1 is a plan view of the burner;

FIGURE 2 is an enlarged section on the line 22 of FIGURE 1;

FIGURE 2A is an elevational detail on the line 2A-- 2A of FIGURE 2;

FIGURE 3 is a section on the line 33 of FIGURE 1;

FIGURE 4 is a section on the line 44 of FIGURE 2;

FIGURE 5 is a section on the line 5-5 of FIGURE 4;

FIGURE 5A is a section on line 5A.5A of FIG- URE 5;

FIGURE 6 is an exploded view of the burner;

FIGURE 7 is an enlarged ection through the nozzle; FIGURE 8 is a section on the line 88 of FIGURE 7;

FIGURE 9 is an exploded view of the nozzle; and FIGURES 10 and 11 are sections on the lines 1010 and 1111-of FIGURE 9, respectively.

Referring first to FIGURES 7 to 11, the nozzle 1 (FIG- URE 7) comprises the nozzle sleeve 2, the nozzle tip 3, and the nozzle body 4 which provides the air inlet 5 (the only inlet for air under pressure) and oil inlet 6. The nozzle is mounted in the burner by its threads 7 being screwed into the threaded collar 8 of the nozzle holderand-spacer 9. Generally, all secondary air is drawn into the burner by the current of gases passing through the burner, initiated by the primary air introduced through inlet 5. The volume of the gases increases as they pass through the burner due to their being heated and the partial combustion which takes place within the burner.

The nozzle is assembled by slipping a metering insert 10 or 10' (FIGURES ,9-11) or the like, with a suitable opening 11 or 11' or the like, into the sleeve. The size of the opening controls the amount of oil aspirated into the combustion chamber. The metering insert may be omitted altogether to supply the maximum amount of oil. Thus, the amount of oil supplied to the burner is established, and is not changed thereafter unless some change is made in the oil requirements. The washer 12 of nylon or the like which is sufficiently resilient to prevent rattling, is first put into the bore of the body 4. The sleeve and insert are then put in place and the tip is screwed into the body to hold the sleeve in place.

The end 24 (FIGURE 7) of the sleeve which is nearest 7 and 8) in the outer surface of the nozzle, between the nozzle and the spacer 29 (FIGURE 7) which abuts the body of the nozzle at the air inlet 5.

The aspirated oil passes out through the nozzle tip 3 into the burner where the air diffusers 45 and 46 accelerate its whirling motion and form it into a conical spray. The spray passes through the electrode assembly 48 and into contact with the inner screen 50 (FIGURE 2) in the combustion chamber. There are two electrodes 52 and 53 within the electrode assembly. 7

The combustion chamber 60 (FIGURES 1, 2, 5 and 6) is provided with identical screen retainers 62 and 64 (FIGURES 2 and 5). The outer screen 66 fits inside of the outer prongs 68 (FIGURES 5 and 6) of the screen retainers and the middle screen 7 fits inside of the inner prongs 72 of these retainers 62 and 64. The ring 74 (FIG- URES 2 and A) is welded to inner screen 59 before this screen is assembled in the burner. This ring 74 is registered against the back retainer ring 7 6 (FIGURES 2, 5, 5A and 6) and limits the extent to which this screen can be slid into the burner. The prongs 77 on ring 76 provide just room enough to accommodate the screen 50 within them. Before assembly in the burner, these prongs 77 are peened at 78 (FIGURE 5A) to cause them to become enmeshed in the screen.

The front plate 80 is held by rivets 81 to narrow bracketjs 82 which extend through the notches 84 (FIGURE 6) in the combustion chamber 61} and their inner ends are notched at 86 to abut against the burner retainer screws 88. These screws extend through openings 90 in the nozzle holder and spacer 9; openings 93 and 94 in the air diffusers 45 and 46; openings 95 and 96 in the gaskets 97 and 98; openings 99 in the porcelain housing 48 of the electrode assembly; openings 100 in the gasket 102; openings 104 in the back retainer ring 76; partial openings 108 in the screen retainer 62; partial openings 110 in the screen retainer 64; openings 112 in the combustion chamber 60 and then through openings 114 in the back plate 116. They are held in place by the hex nuts 118 which are separated from the back plate by lock washers 120.

The electrical conductor 122 (FIGURES l and 3) is provided with an opening at one end through which one of the screws 88 (FIGURE 3) passes, and at the other end there is an opening in which the electrode 52 is held by the nuts 126. The other electrode 53 passes out to the recess 130 in the electrode housing 48 and it is here connected with the terminal 132. The electrodes are insulated from the metal housing. The inner ends of the electrodes extend up into the path of the oil mist as shown in FIG- URE 3 and secondary air sucked through opening 134 (FIGURES 1 and 2) diffuses the spark into the chamber. Alternatively, the inner ends of the electrodes may be located within the recess 135, and in that case the spark is drawn into the path of the oil mist by the current of air drawn into the burner through the opening 134.

The diffusers 45 and 46 are identical. They are stamped from sheet metal. There are three wings 140 on each of these air diffusers and they extend in from the main portion of the diffuser as shown in FIGURES 2, 3 and 6. These wings are cut from the center of the stamping, a part of which is removed. In installing these diffusers which are identical, the outer annular portions are brought into flat contact, and are turned so that the holes in the annular portions coincide and the wings of the respective diffusers are located between one another as best shown in FIGURE-3. As perhaps best shown in FIGURE 6, one portion of the, base of each wing is integral with the outer annular portion of the diffuser, and the other portion is cut away so that when the wings are angled out as shown in FIGURE 2 they impart a swirling conical motion to the air stream as it passes through them. This gives an additional swirling motion to the subsequent spray as it passes through the electrode assembly and out through the screens.

The outer and inner prongs 68 and 72 on the identical screen retainers 62 and 64 are bent in as best shown in FIGURE 6. These prongs are bent in at different distances from the center of each retainer, as clearly shown in FIG- URE 5. The outer edges of the respective retainers are flanged toward one another, and they are notched at 141 to receive the brackets 82 on the back plate (FIGURE 6). These notches coincide with the notches 84 in the rim of the combustion chamber 60.

The drawings illustrate a new burner as it is received from the manufacturer. In each of the gaskets 97 and 98 there are but two openings 143 in addition to openings 94 and for the screws 88. These are on opposite sides of the gaskets. These openings 143 coincide with openings in the other elements and are designed to channel a measured amount of secondary air into the combustion chamber. When a burner is installed in a particular piece of equipment, such as a clothes drier or furnace, etc., it will be known how much secondary air will be required for the amount of oil it will utilize. If the two openings in each gasket are not enough to supply the required secondary air, one or more additional holes are readily punched in all of the gaskets simultaneously by inserting a sharp implement into one or more additional openings provided in the stampings, etc., starting at the holder 9 and extending through the several elements until the im plerne-nt has passed through the gasket 102. As explained, more or less oil is supplied to the burner by proper seleetion of the insert 10 or 10" or other insert. Thus the burner described is adapted to serve in equipment hav ing widely different calorie requirements or firing fates.- Any additional holes required in the gaskets are preferably distributed uniformly about the edge of the burner, as the holes provided in the metal stampings permit.

In operating the burner, secondary air is drawn into the burner through the openings (FIGURE 6) in the holder 9 to be mixed with the aspirated oil immediately after it leaves the nozzle.

It is essential to introduce additional secondary air into the combustion chamber 60 outside of the outer screen 66 (FIGURE 2). This is supplied through two or more of the holes, just described, which are provided in the outer portion of each of the various elements, as best shown in FIGURE 6. One such opening is indicated by the numeral 152 and arrow in FIGURE 2. This secondary air is mixed with oil mist in the space around the outer screen 66 (see FIGURE 2) and returned as a gasified mixture through the screen pattern to be mixed with the gases which are carried through and out of the combustion chamber to a supplemental burner where the gases derived from the oil and air are burned. In order to provide this additional secondary air, coinciding openings are provided in the various elements as best shown in FIGURES 2 and 6. The number of such openings in each burner which are effective for the introduction of second ary air is limited to the number of openings provided in the several gaskets, as above described. The air is drawn into the space in the outer portion of the combustion chamber through these openings by the current of the aspirated oil and gases passing through the burner. Only enough air is supplied to the burner to partially oxidize the oil. Sufficient combustion takes place within the burner to raise the temperature of the screens to red or white heat producing infra-red radiation. The inner screen 50 becomes the hottest. The openings 155 (FIG- URE 2) in it are present to provide an element of back pressure desirable for easy, quiet starting. Because the air supplied to the burner is sufficient to onlypartially burn the oil, the gases leaving the combustion chamber are called starved gases.

The oil drawn up into the nozzle leaves the tip 3 as a cone. It meets air introduced through channels 28 and the oil and air are given a spiral, conical motion as they pass through diffusers 140. The combustion chamber 60 is so located that the conical spray contacts the inner screen 50 within the combustion chamber. Much of the outer portion of the cone of the oil mist passes throu h "the inner scr en and some passes through the middle screen and also some thr ugh the other screen. It is driven outwardly by the spiraled conical How of the air and oil mixture. It moves outwardly through that portion of the screens nearest the back plate 116 anti then circulates back and is returned through the forward portions of the various screens 'in the general location of the combustioh chamber adjacent the back retainer ring 106. The interception of the spiral spray by the screens produces intense agitation of the gases withinthe burner. As the ga'sified mixture passes back through the inner screen 50 it is mixed with the gaseous mixture flowing through the burner and is carried aloh'g'w'i'th it to the supplemental burner where it is consumed. Thus there is a constant outhow of oil. mist outwardly over the various hot screens and back. again throughthe screens with secondary air which gasifies it. The oil is only partially burned. The resulting gas is mixed with the general stream of the gaseous mixture which flows through the burner and out to the supplemental burner where it is completely burned. In starting up the burner, the oil mist is ignited and the temperature within the burner quickly rises and heats the screens. As the contents of the burner approach the final operating temperature, all (or substantially all) of the oil is transformed into gas within the combustion chamber by reaction with the air, and the resulting gases pass out of the burner to the supplemental burner which may be of any suitable construction.

Safety means, etc. are provided as required, the device in FIGURE 1 identified by the numeral 160 being a flame sensor.

The invention is covered in the claims which follow. What we claim is: 1. An oil burner which includes: an oil inlet, a primary air inlet, means for producing a conical spray of the oil in the air and a passage for the spray leading therefrom,

electrodes in the passage to ignite the oil in the spray,

screen means located so as to be contacted by the spray and heated to incandescence from partial combustion of the oil in the spray, said screen means surrounding the passage and separating it from a chamber exterior of the passage which is closed exteriorly of the screen means except for an inlet for secondary air, and

means for conducting secondary air into said exterior chamber.

2. The burner of claim 1 in which:

the screen means is metallic and is arranged as a series of successive screens through which the spray passes.

3. The burner of claim 1 in which the screen means includes means for preheating the secondary air before it contacts the portion of the screen means which defines the passage.

4. The burner of claim 1 in which there is a circumferential enlargement in the passage and the screen means is cylindrical and is over the entrance from the passage into the enlargement.

5. The burner of claim 4 in which several cylindrical metal screens in the enlargement separate the passage from the means for introducing secondary air into the burner.

6. The burner of claim 1 in which there are separate elements which individually comprise:

(1) the portion of the burner in which the oil inlet and primary air inlet are located,

(2) the electrodes, and

(3) the portion of the burner which contains the screen means, and

there are aligned openings in the margins of each of said elements, screws passing through some of the aligned open- '6 tags holding the dihere'nt elements together; and there is at least one passageway formed by additiohal aligned openings which forms at least one of said means for introducing secondary air into t r. '7. The burner of cl-aim 6 in which there is "a gasket between at least two of the elements, there is at ieast one less aligned opening in the gasket than in the other elements and the gasket blocks a passage torsecondary air formed by aligned openings. 8. The burnei of claim 1 having in the portion adjacent a tor the entering air which is composed of identical parts with hat marginal 'polftions which are in contact with one another, with wings angling inw r cll away from said portions to impart a whirling conical motion to theenterin-g air, the wings on one ai' ruse-r being located between the wings on the other diffuser.

9. The hunter of elatin 7 in which marginal openings in the elements for (1) the screws and (2) the formation efpassa for secondary air around at least a substantial portion of each element are evenly spaced, and there is adjacent the inlets for oil and primary air a fd'iituser' for the entering air which is composed of identical parts with flat marginal portions with open in'gs in at least a portion of each marginal portion spaced the same as in the other elements, with diffuser wings angling away from the entrance into said passage for-the air to a whirling conical motion to the entering spray, said openings and wings being so spaced that by passing the screws through openings in the respective diffusers which are differently located with respect to the wings, the wings on the one diffuser are located between the wings on the other diffuser.

10. The burner of claim 1 which includes:

a nozzle in which the inlets for oil and primary air are located, and one end of the nozzle is held in one end of the wall that forms the passage, and

this end of the nozzle is notched and passages exist between the notches and wall for the introduction of secondary air.

11. The burner of claim 1 which includes a nozzle in which the oil inlet is located:

an oil passage through the nozzle which is formed in a metering part removable from the nozzle, and

parts of the nozzle are threaded for easy separation to gain access to said metering part.

12. The burner of claim 11 in which the removable part is a cylinder with a groove in one surface, which part is adapted to slide in the oil passage leading from the oil inlet.

13. The burner of claim 5 in which each of the several screens surrounds the passage and these screens are sup ported in identical retainers in each of which there is an opening large enough to prevent obstruction of the gases passing through the passage,

each retainer having concentric series of prongs projecting from one surface,

the prongs of each series being adapted to position one of the screens.

14. The process of burning oil which comprises:

mixing the oil with air and forming a spray therefrom,

igniting and only partially burning the oil in the spray in a combustion zone, and

passing the burning mixture through screen means and thereby heating at least a part of the screen means to a temperature at least the temperature of red heat,

said mixture being confined after passage through the screen means, and admitting secondary air thereto and mixing it therewith and thereby producing a combustible gas from the mixture, and

passing this mixture through the screen at said temperature into said combustion zone.

15. The process of claim 14 in which said secondary air is heated by said screen means.

16. The process of claim 14 which comprises:

passing said combustible gas miXture from the combustion zone to a combustion chamber and there completely burning the combustible matter in the mixture.

17. An oil burner which comprises a combustion-chamher, an oil inlet and a primary air inlet, a nozzle adjacent to which said oil and air inlet are connected and which is in one end of the chamber into which an oil-air mixture is sprayed by the nozzle, perforate partition means within the chamber which separates a portion of the chamber through which partition means some of said oil-air mix ture is admitted to this portion and in burning raises the partition to incandescence, openings for introducing secondary air to the chamber and to said portion, there being no other opening in said portion, and ignition means for the oil between the nozzle and said partition.

18. The burner of claim 17 in which the partition means is cylindrical and separates an annular peripheral portion from the rest of the chamber.

19. The method of operating a burner which comprises 25 forming an oil spray with insuificient air for complete combustion of the oil, introducing the spray into one end of a combustion chamber one portion of which is separated from the remainder of the chamber by a perforate guide and igniting at least a portion of the mixture before 30 it reaches said guide, passing some of the spray with air through the guide and mixing it with secondary air in an amount insufficient for complete combustion of the combustible matter then present in the mixture with partial combustion of said combustible matter to gases taking place in said portion of the chamber separated by the guide.

20. The process of claim 19 which includes returning said combustible matter, while burning, to the combustion chamber and mixing it there with oil-air mixture, and passing the resulting incompletely burned mixture out of the other end of the chamber to a combustion zone and burning it.

References Cited UNITED STATES PATENTS 329,844 11/1885 Mulloy 1581.5 1,355,443 10/1920 Auger 158-76 1,450,229 4/1923 Robinson 15873 2,869,626 1/1951 Sherman 1584 3,124,193 3/1964 Klein 158-53 3,131,749 5/1964 Davis 158-4 3,221,796 12/1965 Nesbitt 158-1.5

FOREIGN PATENTS 815,643 7/ 1959 Great Britain.

FREDERICK L. MATTESON, JR., Primary Examiner.

E. G. FAVORS, Assistant Examiner.

Claims (1)

1. AN OIL BURNER WHICH INCLUDES: AN OIL INLET, A PRIMARY AIR INLET, MEANS FO PRODUCING A CONICAL SPRAY OF THE OIL IN THE AIR AND A PASSAGE FOR THE SPRAY LEADING THEREFROM, ELECTRODES IN THE PASSAGE TO IGNITE THE OIL IN THE SPRAY, SCREEN MEANS LOCATED SO AS TO BE CONTACTED BY THE SPRAY AND HEATED TO INCANDESCENCE FROM PARTIAL COMBUSTION OF THE OIL IN THE SPRAY, SAID SCREEN MEANS SURROUNDING THE PASSAGE AND SEPARATING IT FROM A CHAMBER EXTERIOR OF THE PASSAGE WHICH IS CLOSED EXTERIORLY OF THE SCREEN MEANS EXCEPT FOR AN INLET FOR SECONDARY AIR, AND MEANS FOR CONDUCTING SECONDARY AIR INTO SAID EXTERIOR CHAMBER.

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