US2072587A - Burner - Google Patents

Description

, 1933 4 sheets-'sheety V1 BURNER Filed Aug. 19

J. E. GREENAWALT March 2, 1937.

March 2, 1937. J. E. GREENAWALT BURNER Filed Aug. 19, 1953 4 Sheets-Sheet 2 VII/1 /NVEA/To/e:

Joh/N E. GREEN/:WALK

March 2, 1937.

J. E. cam-:ENAWAL'rA BURNER Filed Aug. 19, 1933 4 Sheets-Shea*I 3 yo La Hrro/e/VEK Patented Mar. 2, 1937 UNITED STATES PATENT OFFICE d ai.

invention relation to improvements in burners particularly adapted for the burning of liquid fuels, such as oil. and it consists in. the novel features of construction more fully set forth in the specification and pointed out in the claims.

The essential features of the invention are directed to the means for carbureting and distributing the fuel over a wide area so that com- 1o bustion may be complete and productive of intense heat.

The principal object of the invention is, therefore, the provision of a. burner having a fuel distributing head which subdivides the fuel into very l5 minute particles and at the same time mixes with it a part of the air necessary for its combustion so' this combustion may be rapid. n further object is to provide a. secondary supply of air to insure complete combustion of the fuel.

Another object is to provide means for impelllng the mixed air and fuel outwardly under sumcient velocity from the fuel distributing head to prevent the combustion of the fuel within the head. A still further object is to embody within the fuel distributing head fan blades for insuring an adequate supply of air for primarily mixing with the fuel. These objects, as well as other advantages which are inherent in the invention, will be better apparent from a detailed description of the-same in connection with the accompanying drawings, in which:

Figure 1 is a side elevation'of my improved burner mounted for operation in connection with a down draft furnace which is shown in longitudinal section; Fig. 2 is a middle vertical longitudinal section through the burner and that partof the furnace immediately adjacent to the burner; Fig. 3 is a plan view of the inside of the fuel distributing head disk showing the arrangement of the blades which also form passage-ways for the fuel; `Fig. 4 is a horizontal cross-Section through the fuel distributing head taken on a plane indicated by the line 4-4 of Fig. 2; Fig. 5 is a cross-sectional view through a, part of a sintering apparatus showing the application of a modified form of the burner to the igniting hood of said apparatus; Fig. 6 is a middle vertical longitudinal section through the modified form of the burner and that part of the sintering apparatus igniting hood immediately adjacent thereto, Fig. '7 is a cross-sectional detail taken on a plane indicated by the line 1-1 of Fig. 6, Fig. 8 is a cross-sectional detail taken on a plane indicated by line 8--8 of Fig. 6; Fig. 9 is a crosssectional detail taken on a plane indicated by line mi. 15d-Wi i-i of Fig. 6; and Fig. lu is a plan view ofthe inside of the fuel distributing head wlw of the modiued form of burner showing the arrangement of the blades which also form the passageways for the fuel.

Referring to the drawings, and for the present Figs. 1 to d, inclusive, B represents improved burner positioned in the opening O in the roof R of a down draft furnace F, the combustion chamber C of which is given an annular shape by virtue of a centrally disposed column 1P'. The burner B is carried by a cylindrical housing H which in turn is supported by structural members S which also support the furnace F.

The burner B includes a fuel distributing head i having a tube 2 extending upwardly therefrom which is rotatably mounted within the bearing member 3 supported bythe housing H. The bearing member 3 comprises an upper cylindrical section l and a lower section 4', and in the upper section there are ball bearings 5 and 6 in spaced relation which take both the vertical and lateral thrust of the tube 2 whenV the latter is rotated, as presently to appear. The lower section 4 of the bearing member 3 has an inwardly extending annular flange 1 encompassing the tube 2, and there is a cup-like member 8 fixed to the' tube 2 so as to envelope the ange 1. Considerable packing is disposed between ange 1 and tube 2 to prevent the leakage of the lubricating oil for the ball bearings 6 and B. 'Ihis lubricating oil settles in the well 9 when theburner is not in use and just as soon as the tube '2 is rotated the centrifugal force will force the oil outwardly from the well 9 so that it will enter oil hole I0 and pass upwardly through holes II and I2 to the upper bearing E. This is a mechanical detail that forms no part of the present invention, as this feature may be modified in accordance with well known practices.

The tube 2 forming a part of the distributing head I has a conical inner surface I3 Widening toward the bottom of the tube which terminates in a flange or plate-like member I 4 having a slight downward inclination toward the periphery thereof. On the upper surface I5 of the ange I4 is a plurality of radially disposed ribs or vanes I6 which, as will presently appear, serve as fan blades when the burner is in operation.. A disk or plate-like member I1 having a. central conical boss I 8 and a, series of bosses I9 extending inwardly from the periphery of the disk is bolted against the iiange I4 by means of bolts 20, one of which passes through each of the bosses I9. The upper surface of each of the bosses I9 is inclined to correspond with the inclination of the flange I4 so that when the disk I1 is bolted to the flange I4 the bosses I9 will bear against the inner surface of the flange I4 5 and maintain the flange and disk in spaced relation while the boss I8 projects toward the center of the tube 2. While the bosses I9, or blades, are in a general sense radially disposed, it will be observed Ithat only the side a of each boss lies 10 on the radius of the disk I1, the other side b inclining to the radius so that the blade is considerably wider at the periphery of the disk than toward the center thereof, the bosses I9 thus serve as partitions to divide the fuel passage space between flange I4 ,and disk I1 into a large number of narrow slots or oil passages c. The purpose of Widening the blades at the periphery is to effect a narrowing of the oil passages c toward the periphery of the disk. The advantage of thus narrowing the oil passages toward the disk periphery is to obtain a maximum centrifugal action on the stream and discharge it with sufficient velocity to throw ,the fuel particles away from the disk and thus prevent ignition of the fuel in the passage-ways. This arrangement of the blades also prevents the formation of eddy currents within the fuel distributing head i whereby the iiames outsideof said head might be drawn into the head and cause premature combustion. On the outer surface of disk l1 is a central boss I1' from which radiate a plurality of vanes 2| which operate as fan blades on the distributing head I, as will be apparent from the description of the operation of the burner. A fuel pipe 22 leading from any suitable source of fluent fuel (such as oil) extends through the open end of tube 2 so that fuel will be deposited in a regulated amount against the inside of said tube.

An air inlet pipe 23 controlled by the valve 24 leads into the side of the housing H, and a second air inlet pipe 25 controlled by valve 26 leads into an air port 21 passing through the bottom of the furnace F and the column P. 5 Thus, by regulating the valves 24 and 2G, air in measured quantities will be conducted to both sides of the distributing head I. As explained above, the fuel distributing head is rotatably supported by the bearing member 3 and is adapted to be rapidly rotated by means of a motor M, to which the head is directly connected by means of a shaft 28 keyed to a spider 29 within the tube 2. 30 is an oil cup from which oil is fed through the pipe 3| into the bearing memlber 3.

The action of my improved oil burner is as follows:

The oil is delivered against the inside surface I3 of tube 2 from the feed pipe 22 where it is 60 spun out to a Very thin lm uniformly over the inside surface of the tube by the centrifugal force and surface tension, it being understood that the tube 2 is rotated at a very high rate of speed (approximately 3500 R. P. M.). On ac- 65 count of the conical shape of the tube, it being wider at the bottom than at the top, the oil film moves slowly and evenly downwardly, all the while being whirled around the inner surface of the tube by the centrifugal force. Ulti- 70 mately the oil reaches the flange I4 and as it moves outwardly over the inner surface of this flange it is still further attenuated on account of the increase in diameter as the oil approaches the periphery of the flange. When the oil 75 reaches the bosses I9 between Bange I4 and lower disk I1 it enters the radial fuel passages c, all of said passages receiving approximately the same amount of oil on account of the uniform distribution of the oil by the centrifugal force over the inner surface of the flange I4. By the time the oil passes through the passages c and is about to be discharged therefrom it is not only uniformly distributed around the fuel distributing head I, but is also in a very fine state of division, or atomization, so that it may be very easily and quickly vaporized the instant it enters the combustion chamber C. It is apparent that the division of the oil in the fuel distributing head is with mathematical precision. For instance, there are sixteen blades and of course sixteen oil passages in the head, and if the distributing head is rotated at 3500 R. P. M. the amount of oil flowing through the head per minute is sub-divided into 56,000 parts for uniform distribution around the circumference of the head. The air that flows through the distributing head with the oil is likewise sub-divided and distributed with the same mathematical precision so that each atomized particle of oil will be surrounded and mixed with exactly the same amount of air as every other particle of oil. Of course, air is sucked into the tube 2 through the open top thereof and this air is thoroughly mixed with the particles of oil discharging from the passages c. Air also passes through the housing H and through the port 21 to both sides of the fuel distributing head I and enters the combustion chamber C on both sides of the circular spray of mixed fuel and air issuing from the distributing head I. There are thus two air supplies for the fuel, the primary air supply entering the combustion chamber C intimately mixed with the fuel from the distributing head I, and the secondary air supply entering the combustion chamber on both sides of the spray of mixed fuel and air. I have found in practice that the amount of primary air should be between 20% and 50% of the entire air supply required for complete combustion, the amount of secondary air, of course, not being so critical provided there is sufficient secondary air.to complete the combustion of the fuel. The velocity with which the secondary air passes into the combustion chamber C is increased by the vanes I6 on the flange i4 and vanes 2| on the disk I1. 0f course, the same result may be obtained by increasing the pressure at the source of supply of the secondary air.

The high rotative speed of the distributing head i causes an intense turbulence in the combustion chamber C. This turbulence expedites the mixing of the atomized fuel and the air so that an explosive mixture is obtained almost as soon as the fuel and the air enters the combustion chamber C. Therefore, combustion proceeds immediately and continuously as the mixed gases are whirled downwardly through the annular combustion chamber on their way to the outlet V.

In the modification, Figs. 5 to '7, inclusive, I show my improved burner adapted for use in connection with a sintering apparatus. This sintering apparatus comprises a sintering pan 40 and an igniting hood 4I which carries the burners B for igniting the charge supported by the grates in the pan, which grates are not shownl but the supporting surface of which is indicated by the line x. The igniting hood 4I carries the fuel tank 42 and the air tank 43 for obtaining the necessary pressure on the fuel whereby it is forced to the burners B'. This arrangement is old and is shown in Patent No. 1,512,284, granted to me on October 21, 1924. The construction of the burners B is slightly different from that of burn- 5 ers B above described, as will be seen by referring to Fig. 6.

. It will be observed that the housing 44 surrounding the tube 45 of the fuel distributing head 46 is open to the atmosphere at the top and the position of this housing withrespect to the distributing head 46 is adjustable by means of studs 41, 41, nuts 48,48 and shims 49, 49. The studs 41, 41 project upwardly from four equally spaced points in the roof plate 50 of the ignition hood 4I, said plate 50 having a circular central opening 5I in which is disposed a flanged sleeve 52 also held in place by the studs 41. The flanged sleeve 52 has its lower edge 53 beveled to correspond with the beveling o'f the upper edge of a plurality of radially disposed fan blades 54 projecting upwardly from the periphery of flange 55 'extending outwardly from the tube 45. The construction of the disk 56 is similar to that of disk I1 of the main form as it is also provided with radially disposed blades 51, between which are formed the oil passage-ways 58 for the distribution of the oil uniformly around the periphery of the distributing head 46. However, disk 56 is provided with a central bore 5S whereby it is secured to the reduced end 60 of shaft 6I connected by a suitable coupling 62 to shaft 83 of the motor M. Also fixed on shaft BI within the tube 45 is a fuel cup 64, the inner surface of which tapers outwardly toward the top so that the fuel oil may be more easily expelled from the cup by centrifugal action when the distributing head 46 and fuel cup 64 are rotated with the shaft 6 I An oil feed pipe 65 has a funnel 66 on its upper end and oppositely disposed branches 61, 61 on its lower end, which branches lead into the fuel cup 64. The oil is discharged into the funnel 68 through a pipe 68 leading from the oil tank 42.

In the modification Figure 6 it will be observed that the fan blades 54 are shorter than the blades 45 I6 of the main form'IFig. 2). l'I'he purpose of this is to concentrate the movement of the secondary air at the periphery of the fuel distributing head 46.

The general operation of the modified burner 50 B' is the same as that of burner B except that the secondary air supply which passes through the i housing 44 is forced outwardly by the peripheral fan blades 54 and discharged with considerable velocity into the ignition hood 4I. The volume 55 and velocity of the incoming flow of secondary air is controlled by adjusting ,the housing 44 vertically so as to increase or decrease the space" between the lower edge of the housing and flange 55. The oil is distributed on the inner surface 60 of the tube 45 by centrifugal action as itis thrown over the top edge of cup 44 as this cup rotates during the operation of the burner. Of course, after the oil is distributed over the inner surface oi' tube 45 its action is the same as in the main form heretofore described, the centrifugal force causing it to spread in a very thin illm over the 5 inner surface of the tube and into the passageways 58 from which it emerges in a very finely divided state thoroughly mixed with the primary air sucked in ,through the tube 45 as the distributing head 46 is rotated. Al0

Having described my invention, I claim:

1. In a burner for fluent fuel, a fuel distributing device comprising a tube having its upper end open to provide an air intake, fuel feeding means for discharging fuel into the tube, a fuel disl5 tributing head at the lower end of the tube, said i distributing head having a hollow annular flange having within it spaced radial fan blades extending a substantial distance inwardly from the periphery of the flange, the spaces between blades 20 constituting fuel ports communicating with the tube and leading to the peripheral surface of the flange, said ports being tapered to provide constricted outlets for causing the fuel to be ejected from the flange with high velocity, means for ro- 25 tating said tube and head to effect distribution of the fuel by centrifugal action, andI means on said-distributing head for impelling the fuel and air mixture outwardly from the distributing head.`

2. In a burner for fluent fuel, a fuel distribut- 30 ing device comprising a tube open at one end to permit ingress of air to the tube, means for feeding fuel into said tube, a fuel distributing head at the end of the tube opposite to the open end, said head comprising an annular flange inclined 35 downwardly and outwardly of the tube and a disk secured to said flange in spaced relation therewith, a plurality of wedge-shaped partitions between the flange and disk, said partitions being uniformly spaced around the periphery of the4 40 head to form passageways for the fuel and air mixture, and the shape of the partitions being such that the passageways are narrower at the center of the head than at the periphery thereof, the space between the members being in com- 45 munication with the adjacent end of the tube, and means for rotating the fuel distributing device.

3. In a burner for liquid fuel, a fuel distributing device comprising a fuel impeller of the gen- 50 eral shape of a hollow disk, said impeller having within it radially disposed passageways for the fuel, a tube in communication with the inside of the disk, a centrally disposed fuel receiving and distributing cup within said tube, means for feeding fuel into said cup, and means for rotating said fuel distributing device whereby the fuel is' centrifugally discharged from said cup onto the inner surface of said tube and from said tube into the impeller. s

JOHN E. GREENAWALT.

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