US3143089A

US3143089A - Full burner assembly

Info

Publication number: US3143089A
Application number: US253781A
Authority: US
Inventors: Jr Gilbert C Whitney; Kenneth E Lee
Original assignee: Foster Wheeler Inc
Current assignee: Foster Wheeler Inc
Priority date: 1963-01-08
Filing date: 1963-01-08
Publication date: 1964-08-04
Anticipated expiration: 1981-08-04

Description

Aug. 4, 1964 s. c. WHITNEY, JR.. ETAL FULL BURNER ASSEMBLY R 1 m] w Y, R m WE o m m T .IM M a 1 WE m a H N @K m w 3 6 w. a m J d R 1 F g- 4, 1964 G. c. WHITNEY, JR., ETAL FULL BURNER ASSEMBLY 4 Sheets-Sheet 2 Filed Jan. a, less INVENTOR GILBERT C. h fl/r/ve'n-JR.

KENNETH E, LEE- BY ATTORNEY g- 4, 1964 G. c. WHITNEY, JR., ETAL 3,143,089

FULL BURNER ASSEMBLY Filed Jan. 8, 1963 4 Sheets-Sheet 3 INVEN'IOR GILBERT CI WHITNEY, 7?.

BY Ham/57w 5. 5

ATTORNEY United States Patent Office 3,143,089 Patented Aug. 4, 1964 3,143,089 FULL BURNER ASSEMBLY Gilbert C. Whitney, Jr., and Kenneth E. Lee, Dansville, N.Y., assignors to Foster Wheeler Corporation, New York, N.Y., a corporation of New York Filed Jan. 8, 1963, Ser. No. 253,781 11 Claims. (Cl. 110-28) This invention relates to fuel burners and more particularly to fuel burner assemblies capable of controlling the direction of the flame from the nozzles of the burners.

This application is a continuation-in-part application of United States Patent applications, Serial Nos. 728,671 (now abandoned) and 847,596, filed April 15, 1958, and October 20, 1959, respectively.

Heretofore, one means for achieving control of the direction of flow of fuel from the burner nozzle, and hence, the direction of the burner flame into a combustion chamber, has been to provide burners with complex air register assemblies and actuating mechanisms for adjustment of the vanes or doors of the air registers whereby control of secondary air flow to the area of the burner nozzle outlet is effected. Another known means for achieving control of the direction of flow of fuel discharged from the burner nozzle, has been by providing the burner nozzle with a pivotal burner tip and a relatively complex burner tip actuating mechanism. The disadvantage of the foregoing burner structures is the complexity and the relatively high cost of fabrication and, in the case of the pivotal burner tip structure, control of flame direction can only be effected in one plane. A further disadvantage of present burner assemblies is the relatively large pressure drop in secondary air in flowing between the windbox and the burner nozzle outlet which necessitates the use of relatively large blowers to obtain a relatively high pressure in the windbox to compensate for the expected pressure drop at the burner nozzle outlet.

Accordingly, it is an object of the present invention to provide a relatively simple and inexpensive burner assembly wherein control of the direction of the flame burst therefrom can be achieved in a plurality of planes. Another object of this invention is to provide a burner structure wherein the pressure drop of secondary air through the burner structure is greatly minimized. A further object is to provide a burner structure having improved secondary air distribution peripherally of the burner nozzle fuel outlet whereby improved burner flame characteristics are achieved.

The present invention contemplates a novel burner assembly comprising a housing for receiving combustion air from a suitable source thereof, the housing having an outlet opening therein and a burner nozzle projecting through the outlet opening. The burner nozzle is connected at one end to receive fuel from a suitable source thereof and is provided with an outlet at the opposite end for discharging fuel for combustion. A first ring-shaped baffle or skirt is disposed in superimposed relationship over the burner nozzle and is secured to the nozzle adjacent the outlet. The baffle extends from the point of connection with the burner nozzle, through the outlet of the housing, and into the interior of the latter. A second ring-shaped baflie of larger dimensions than said first ringshaped baffle is disposed in superimposed coaxial relationship to said first bafiie. The second ring-shaped baflie is disposed to extend from a point adjacent the burner nozzle outlet into the housing outlet. Means are provided for supporting the second baflie in spaced relationship to said first bafile so that an annular combustion air passageway is defined between the baffles which pas sageway communicates at one end with the interior of the housing to receive combustion air and at the other end communicates with the outlet of the burner nozzle to discharge combustion air peripherally of the nozzle outlet. A second means is provided for supporting and moving the second bafile relative to the first bafile to vary the axis of the flow of combustion air with respect to the longitudinal axis of the burner nozzle and flow of the fuel from the burner nozzle and thereby control the posi tion of the burner flame produced by the combustion of fuel discharged from the burner nozzle.

As an embodiment of the invention, the secondary air passageway may be defined by the outer or second ringshaped baffle and the burner nozzle, the first ring-shaped baflle or skirt being omitted. Preferably the burner nozzle has a frusto-conical configuration, so that the passageway, as with the embodiment described above, has a long radius curvature extending from a large circumference end in communication with a source of combustion air and terminating at a small circumference end in communication with the discharge end of the burner nozzle.

Although this embodiment may result in a slightly increased pressure drop of secondary air, over the first described embodiment, it is found that the pressure drop is significantly less than with conventional assemblies, and further that a much improved distribution of secondary air peripherally of the burner nozzle discharge end is achieved, with improved burner flame characteristics and control, as with the embodiment described above.

The invention will be more fully understood from the following detailed description thereof when considered in connection with the accompanying drawings, in which:

FIG. 1 is a sectional view in elevation of a fuel burner assembly according to the present invention;

FIG. 2 is an end view of the fuel burner assembly of the present invention as viewed from the left in FIG. 1, with parts broken away for illustration purposes;

FIGURE 3 is a fragmentary view in perspective showing the manner of supporting the burner assembly;

FIG. 4 is a sectional view taken substantially along line 44 of FIG. 1;

FIG. 5 is an enlarged fragmentary view of the support and adjustment assembly according to this invention; and

FIG. 6 is a view in section taken substantially along line 6-6 of FIG. 1.

Referring now to the drawings, 10 generally designates the burner assembly according to the invention for combustion of pulverized fuel. Burner assembly 10 is disposed exteriorly of a wall 11 of a combustion chamber (not shown) adjacent a burner port 12 provided in wall 11. The burner assembly 10 comprises a housing or windbox 13 having a top wall 14, bottom wall 15, opposite side walls 16 and 17 (FIG. 2), a rear wall 18 and a front wall 19, which walls are joined together to form a fluid-tight enclosure or plenum chamber 20. An air duct 21 is connected at one end to the bottom Wall 15 of windbox 13 and at the other end to a source of second ary air under pressure (not shown), such as a fan. Flow of secondary air into chamber 20 is controlled by a damper 22 disposed within air duct 21. Front wall 19 is provided with an outlet opening 23 therein.

A pulverized fuel burner 24, comprising a burner nozzle or injector 25 and a volute entrance section 26, is disposed and suitably supported in windbox 13 so that burner nozzle 25 extends horizontally through windbox outlet opening 23 to a point adjacent burner port 12. Burner nozzle 25 may be provided with spaced helical ribs on the interior surface thereof or straight ribs as disclosed in US. patent application Serial No. 446,532, filed July 29, 1954 now Patent No. 2,912,942 and a suitable ignitor (not shown) coaxially arranged therein. The volute section 26 is connected to a pulverized fuel and air feed pipe 27 which extends through top wall 14 of windbox 13 and is connected to a suitable source of pulverized fuel and air (not shown). The mixture of pulverized fuel and air is fed to the volute section 25 by feed pipe 27, and thence flows through burner nozzle 25, and is discharged from the burner nozzle outlet 28 into burner port 12. Secondary air supply necessary to support efficient combustion of the fuel is delivered to the burner nozzle outlet 28, as hereinafter described.

An open-ended bell-shaped skirt or baiile 29 is disposed over and in coaxial relationship with burner nozzle 25 and is suitably secured along its smaller diameter end, as by welding at 30, to burner nozzle 25 adjacent outlet 28 of the latter. Baffle 29 is dimensioned so that it extends from its connection with the nozzle rearwardly, through outlet opening 23 in front of wall 19 of windbox 13, to a point adjacent volute section 26 and feed pipe 27. A second open-ended bell-shaped baflle 31 of substantially the same configuration as baflle 29, but of substantially larger dimensions than bafiie 29, is disposed in superimposed coaxial relationship with bathe 29 and nozzle 25. Bafile 31 is dimensioned and positioned so that its smaller diameter end portion 32 projects into burner port 12 and extends rearwardly from end portion 32, through outlet opening 23 in front wall 19 of windbox 13, to a point within plenum chamber 20 adjacent the larger end of baflle 29. Baflle 31 is supported in spaced relationship to baffle 29 and nozzle by support and adjustment means, hereinafter described.

Ballies

29 and 31 define therebetween a secondary air passageway 33 which, as in longitudinal section has a long radius curvature. Passageway 33 communicates at one end with the interior of windbox 13 to receive secondary air from plenum chamber 20 and at the opposite end communicates with the burner nozzle outlet 28 to deliver secondary air around the periphery of nozzle outlet 28.

Bafile 29 may be provided with a plurality of spaced vanes 34, as best shown in FIGS. 1 and 6, disposed angularly around the outer surface of the balfle to impart rotational movement to the secondary air flowing through passageway 33. It has been found that imparting a small rotary movement to the flow of secondary air in the same direction as the rotational movement of the pulverized fuel and air mixture provides for the maintenance of stable ignition of the fuel.

To support baffle 31 in spaced relationship with baflie 29 and nozzle 25, bafile 31 is provided with four radially extending

arms

35, 36, 37 and 38 which are spaced 90 from each other around the periphery of baffie 31.

Arms

35, 36, 37 and 38 extend from bafile 31 to a point slightly beyond the plane of top wall 19,

side walls

16 and 17 and bottom wall 15 of windbox 13. The distal end portions of

arms

35, 36, 37 and 38 are each provided I with a hole 39 which is adapted for connection to support and

adjustment assemblies

40, 41, 42 and 43, respectively, hereinafter more fully described.

Burner assembly 10 is secured to combustion chamber wall 11, adjacent burner port 12, by two spaced parallel I-

beams

44 and 45 which are connected to and extend horizontally between two vertically extending I-beams or buckstays 46 and 47 (FIGS. 1 and 2). As best shown in FIGS. 1 and 3, windbox 13 is secured at rear wall 18 to I-

beams

44 and 45 in a suitable manner, as by brackets riveted to the beams, so that the respective legs 48 and 49 of the I-

beams

44 and 45 extend, respectively, beyond the plane of top wall 14 and bottom wall 15. The

opposite legs

48A and 49A of the respective I-

beams

44 and 45 are also secured to a metallic ring 50 which lines the peripheral surface of a recess 51 in the exterior surface of the combustion chamber wall 11.

To seal off the space between combustion wall 11 and the windbox 13 from the air surrounding the fuel burner assembly 10, the spaces between I-

beams

44, 45 and 47 and front wall 19 of the Windbox is closed by an L-shaped sealing plate 47A which extends between and is welded to I-

beams

44 and 45 and to the outer leg of I-beam 47, as well as to front wall 19 of windbox 13. A similar L-shaped sealing plate 46A, extends between and is welded to I-

beams

44 and 45 and outer leg of I-bearn 46, to close the space between I-

beams

44, 45, 46 and front wall 19 of the windbox (see FIGS. 1, 2 and 3). The space between I-

beams

44, 45, and 47 and the metallic ring 58 lining recess 51 of wall 11 is closed by a plate 59A which is disposed in abutment against the inner leg of I-beam 47 and

legs

48A and 49A of I-

beams

44 and 45, respectively, to which legs plate A is welded. Plate 50A is provided with an arcuate-shaped edge portion which abuts ring 50 and is welded thereto (see FIGS. 3 and 6). A plate 563, similar to plate 50A is welded to I-

beams

44, 45 and 46 and to the metallic ring 50, in the same manner as plate 50A, to close off the space between I-

beams

44, 45 and 46- and ring 50. L-shaped

sealing plates

46A and 47A and plates 58A and 50B, seal oif the space between windbox 13 and combustion chamber wall 11 from the surrounding air to thereby prevent secondary air leakage, through outlet 23 in front wall 19 of the windbox, to the atmosphere.

Each of the support and adjustment assemblies comprise an actuating rod 52 having a threaded end portion 53 and an opposite end portion threaded at 54. A sleeve is secured, as by welding, swaging, or the like, to each of the rods to provide an enlarged body portion 55 adjacent threaded end portion 54. The end 56 of enlarged body portion 55 adjacent end portion 54 is cut back on either side of a horizontal center line, the purpose of which will become apparent hereinafter. Each of the actuating rods 52 is provided, as best shown in FIG. 1, with a slot or keyway 52A, the purpose of which will be hereinafter explained.

Actuating rod 52 of support and adjustment assembly 40 is supported above and centrally of top wall 14 by a bearing plate 58 which is secured to top wall 14 midway between

side walls

16 and 17, and by two aligned holes 59 and 60 in the

respective legs

48 and 48A of I-beam 44. Bearing plate 58 is provided with a hole 61 which is adapted to receive therethrough threaded end portion 53 of actuating rod 52, while holes 59 and 60 are adapted to receive therethrough the enlarged body portion 55 of actuating rod 52. Holes 59 and 60 are so dimensioned that they are tightly embracing body portion 55 but not so tightly as to prevent axial movement of the rod therethrough. To provide additional support for rod 52, a sleeve member 62 is disposed over each of the holes 59 and 60 and is welded to the

respective legs

48 and 48A of I-beams 44. Sleeve member 62 is provided with a pin 62A which extends into keyway 52A of actuating rod 52. Pin 62A and keyway 52A cooperate to prevent rotation of rod 52 and allow axial movement of the latter. End portion 54 of actuating rod 52 extends through hole 39 in arm 35 of bafiie 31, and the arm is secured to the actuating rod 52 by a retaining nut 63 which is turned upon threaded end portion 54 of the rod. Nut 63 is provided with tapered inner surface 64 which is similar to the tapered end 56 of enlarged body portion 55 of actuating rod 52, so that an annular notch is defined between the latter and nut surface 64 having oppositely inclined faces which allow pivotal movement of arm 35 relative to actuating rod 52 (see FIG. 5). A handwheel 65, having an integral flanged hub 66, is turned upon threaded end portion 53 and is supported for rotation Within a bearing socket member 67 which is secured to and forms a part of bearing plate 58.

To move actuating rod 52 axially within hole 61 of bearing plate 58 and holes 59 and 68 of I-beams 44, handwheel is rotated upon threaded end portion 53 of the rod thereby feeding the rod toward or away from combustion wall 11, depending upon the direction of rotation of handwheel 65.

Actuating rod 52 of support and adjustment assembly 41 is supported for axial movement centrally of bottom wall 15 of wind-box 13, in the same manner as actuating rod 52 of assembly 40, by a bearing plate 68, similar to hearing plate 58, and aligned holes 69 and 70 in the respective legs 49 and 49A of I beams 45. Rotation of rod 52 is prevented and axial movement thereof is allowed by a pin which extends into keyway 52A in the same manner as explained with respect to support and adjustment assembly 40. Actuating rod 52 of assembly 41 is also provided with a handwheel 71, similar to handwheel 65, and is connected to arm 36 of baflle 31 by a retaining nut 72 turned upon threaded end portion 54 of rod 52 in the same manner as actuating rod 52 of assembly 40 is connected to arm 35 of baffle 31.

Each of the support and adjustment assemblies 42 and 43 are supported centrally of and adjacent to

side wall

16 and 17, respectively, by bearing

plates

73 and 74 similar to hearing

plates

58 and 68. As shown in FIG. 4, enlarged body portions 55 of actuating rods 52 of assemblies 42 and 43 are supported in holes 75 (FIG. 1) and 76 (FIG. 4), which holes are provided in L-shaped

sealing plates

46A and 47A. Over each of the holes 75 and 76 is secured a sleeve 77 which is provided with a pin, to pin 62A which extends in keyways 52A in actuating rods 52, to prevent rotation of the rods and to permit axial movement thereof. Actuating rods 52 of support and adjustment assemblies 42 and 43 are connected, respectively, to

arms

37 and 38 of baflle 31, in the same manner as actuating rods 52 of

assemblies

46 and 41 are connected to

arms

36 and 37, by retaining

nuts

78 and 79, respectively, similar to retaining

nuts

63 and 72. Actuating rods 52 of support and adjustment assemblies 42 and 43 are each provided with handwheels 80 and 81, respectively, which are supported for rotation within bearing

plates

73 and 74, respectively. Axial movement of actuating rods 52 of assemblies 42 and 43 is effected by turning handwheels 80 and 81 as aforedescribed with respect to actuating rods 52 of

assemblies

40 and 41.

In operation of the aforedescribed burner assembly 10, pulversized fuel and primary air mixture is fed to volute entrance section 26 by feed pipe 27. The mixture of pulverized fuel and primary air passes from the volute entrance section into and through burner nozzle 25. The fuel is then discharged from the burner nozzle outlet 28 into the combustion chamber (not shown) through burner port 12 in combustion chamber wall 11. Simultaneously, with the flow of pulverized fuel and air through the burner nozzle 25, secondary air under pressure is supplied to plenum chamber 261 through air duct 21. Within plenum chamber 20, the secondary air flows into annular air passageway 33 which is defined between

baflles

29 and 31. The secondary air flows through passageway 33 wherein rotary motion is imparted to the air stream by action of the angularly disposed vanes 34. The air is then discharged peripherally of the burner nozzle outlet 28 into burner port 12. The pressure drop of the secondary air flow through passageway 33 is relatively small by reason of the long radius curvature of the passageway which causes initial acceleration of air around the large circumference of the passageway, the velocity of the air stream being maintained with little pressure drop through the passageway. However, there is sufficient pressure drop to insure uniform distribution of secondary air in plenum chamber 26 to achieve uniform peripheral distribution of ,air into annular passageway 33. By reason of the long radius nozzle configuration of passageway 33, a more uniform distribution of air at the burner nozzle outlet 28 is achieved and, hence, improved flame character. The annular long radius nozzle configuration of passageway 33 also minimizes unnecessary and unsymmetrical air turbulence and therefore only a small degree of movement of balfle 31 relative to nozzle 25 is necessary to effect a. change in the direction of the flame. Further improved flame character and stability of the flame is achieved by vanes 34 which impart rotation to the air stream through passageway 33 in the same direction as the rotation of the primary air and fuel mixture passing through nozzle 25.

Change in the direction of flow of fuel from burner nozzle outlet 23, and thereby the direction of the flame in the combustion chamber, may be efiected by moving baflle 31 relative to baflle 29 and burner nozzle 25 through adjustment of one or more of the actuating rods 52 of support and

adjustment assemblies

40, 41, 42 and 43 to cause the off-axial positioning of baflle 31 relative to the axes of bafile 29 and nozzle 25. As illustrated in FIG. 1, if it is desired to direct the flame downwardly into the combustion chamber, handwheel 65 is rotated on threaded end portion 53 of actuating rod 52 of assembly 40 to cause the actuating rod to move axially toward the combustion chamber wall 11 to a position shown by the broken line, while handwheel 71 of assembly 41 is rotated to cause actuating rod 52 to move axially in a direction away from wall 11. Movement of actuating rods 52 of

assemblies

40 and 41

carries arms

35 and 36 of baflie 31 respectively toward and away from the combus tion chamber wall 11 to the positions shown by the broken lines thereby tilting baflie 31 so that baffle 31 within plenum chamber 20 abuts baffle 29, as is also shown by the broken lines in FIG. 1. With baffle 31 positioned as shown in broken lines of FIG. 1, the axis of baffle 31 is changed so that the mass of secondary air flowing through passageway 33 enters the furnace along an axis which is at an angle with repsect to the axis of the primary air and pulverized fuel flow mixture discharging from nozzle 25 thereby causing the flame burst to assume an axis or direction which is at a downward angle with respect to the axis of nozzle 25.

To direct the fuel stream and, therefore, the flame burst upwardly, handwheel 65 is turned so as to retract actuating rod 52 past the original position shown in full lines, while handwheel 71 of support and adjustment assembly 41 is turned so as to move its actuating rod 52 toward combustion chamber wall 11. Axial movement of the actuating rods carries arm 36 toward wall 11 and arms 35 away from wall 11 thereby tilting baflle 31 so that its axis extends upwardly relative to the axes of baflle 29 and burner nozzle 25. In this position, the axis of bafiie 31 is changed so that the mass of secondary flowing through passageway 33 enters the furnace along an axis which is at an upward angle with respect to the axis of the primary air and fuel mixture discharging from nozzle 25 thereby causing the flame burst to assume an axis or direction which is at an upward angle with respect to the axis of nozzle 25.

In the same manner as aforedescribed, the fuel and primary air stream discharged from burner nozzle 25 may be directed in a horizontal plane to the right or left of the burner nozzle axis by effecting a tilting of baifle 31 relative to baflle 29 and burner nozzle 25 through turning handwheels and 81 of support and adjustment assemblies 42 and 43.

If it is desired to direct the fuel and primary air stream in a direction lying in both a vertical and horizontal plane with respect to the axis of burner nozzle 25, adjustment is effected of either actuating rod 52 of

assemblies

40 and 41, depending on whether it is desired to direct the flame above or below the axis of burner nozzle 25, and assemblies 42 or 43, depending on whether it is desired to direct the flame to the right or left of the axis of burner nozzle 25.

By relative adjustment of

assemblies

40, 41, 42 and 43 baffle 31 may be tilted in any direction with respect to baflle 29 andburner nozzle 25 and to any degree between extreme positions thereof whereby precise directional control of the flame burst can be achieved.

It should be apparent that the above support and adjustment assemblies effect a movement of the outer baflle 31 about an imaginary pivot point approximately located in the plane of the burner nozzle outlet and along the longitudinal axis of the nozzle to position the axis of the baflle at an angle relative to the burner nozzle axis. In this way control of the direction of the burner flame is achieved with optimum distribution of secondary air peripherally around the burner nozzle outlet. In particular, the dimensions of the passageway annularly about the nozzle are uniformly maintained, avoiding constricting the passageway in a manner adjacent the outlet to adversely affect flame characteristics. This is particularly important when it is realized that the flow rate of the secondary air is approximately 40 times by weight that of the primary air flow.

It has been found that the angle of change of baflie 31 relative to nozzle 25 achieves an angle of change in the direction of the burner flame which is substantially the same as that of the angle of changeof baffle 31 and therefore only a small angular movement of ballle 31 is needed to effect the same degree of flame direction that is obtained by a conventional pivotal burner tip.

It can be seen readily from the foregoing description that a novel burner assembly has been provided wherein directional control of the flame burst can be achieved through 360 around the axis of the burner nozzle without expensive or complicated structures. It is a burner assembly wherein the pressure drop through the burner is greatly reduced so that windbox pressure need not be as high as in convenitonal intervene type burner assemblies.

It is to be understood that while the burner assembly of the present invention has been illustrated and described as adapted for burning pulverized fuel, the invention is not limited thereto. The invention is applicable to burners constructed for burning gaseous fuel, liquid fuels and the like, without departure from the spirit and scope of the invention.

Although but one embodiment of the invention has been illustrated and described in detail, it is to be exprcssly understood that the invention is not limited thereto.

For example, the involute section need not be disposed within the windbox but may be positioned outside of the rear Wall of the windbox with the burner nozzle extending through the rear wall. In addition, the windbox may be secured directly to the outer surface of the combustion chamber wall.

Further, referring to FIG. 1, it is evident that the bafile or bell-shaped skirt 29 may be omitted so that the passageway is defined by the burner nozzle and the outer bell-shaped baffle 31. Preferably, the burner nozzle will have a frusto-conical configuration such that the secondary air passageway extends, with, substantially, a large radius curvature, from a large circumference end in communication with a source of combustion air to a small circumference end in communication With the discharge end of the burner nozzle. The outer baiile, pivoting about a point located approximately in the plane of the burner nozzle outlet and along the axis of the nozzle, effectively directs the combustion air and controls the direction of the burner flame. without constricting the passageway around the burner nozzle outlet and with a uniform distribution of secondary air and a uniform velocity pattern around the nozzle.

In certain installations, it may be desirable to position the burner nozzle as far away from radiation as is practical without impairing the operation of the burner. In these cases, the pivot point for the baflle may be slightly in front of the burner nozzle but along the axis of the nozzle, the important factor being that the baflle should be pivoted in a manner so that the velocity pattern around the burner remains substantially uniform. A uniform velocity in the annulus around the nozzle is essential to achieve a uniform dispersion rate of fuel in the secondary air stream and a well-shaped flame.

Other variations can be made in the arrangement of parts, as will be understood by those skilled in the art, without departing from the spirit and scope of the invention as described in the following claims.

What is claimed is:

1. A fuel burner assembly comprising, a burner nozzle having a longitudinal axis connected to receive fuel from a source thereof and having an outlet to discharge the same for combustion, a source of combustion air under pressure, a bafile arrangement including at least one tubular member encompassing the burner nozzle and coaxial therewith arranged to define with the nozzle an elongated annular passageway of diminishing circumference, said passageway extending from a large circumference end in communication with said source of combustion air to receive combustion air and terminating at a small circumference end in communication with the discharge end of said burner nozzle to discharge combustion air adjacent said burner nozzle outlet, said member being pivotally adjustable about a point approximately located in the plane of the burner nozzle outlet and along the axis of This is accomplished V the nozzle to position the axis of said member at an angle relative to the longitudinal axis of the burner nozzle to vary the direction of the combustion air discharged and to control the direction of the burner flame, and means to pivotally adjust said member.

2. A fuel burner assembly according to claim 1 wherein said burner nozzle is provided with a frusto-conical configuration the small diameter end of which defines the burner nozzle outlet, said tubular member being bellshaped such that the passageway defined by the burner nozzle and said member has substantially a long radius curvature.

3. A fuel burner assembly comprising, a burner nozzle having a longitudinal axis connected to receive fuel from a source thereof and having an outlet to discharge the same for combustion, a source of combustion air under pressure, a baffle arrangement including a pair of substantially coaxial tube-like baflles encompassing the burner nozzle and arranged to define an elongated surrounding passageway of diminishing circumference, said passageway extending from a large circumference end in communication with said source of combustion air to receive combustion air and terminating at a small circumference end in communication with the discharge end of said burner nozzle to discharge combustion air adjacent said burner nozzle outlet, the outer of said coaxial baflles being pivotally adjustable about a point approximately located in the plane of the burner nozzle outlet and along the axis of the nozzle to position the axis of the outer coaxial baffle at an angle relative to the longitudinal axis of the burner nozzle thereby varying the direction of the combustion air discharge and controlling the direction of the burner flame, and means to pivotally adjust said outer baffle.

4. A burner assembly, comprising a windbox having an inlet to receive combustion air and having an outlet opening therein, a fuel injector nozzle having a longitudinal axis, an inlet to receive fuel and an outlet todischarge said fuel for combustion, said nozzle being disposed with a portion thereof extending through the outlet of said windbox and with the outlet of said nozzle being outside of said windbox, a ring member disposed over said nozzle and secured to said nozzle adjacent the outlet of the latter, said ring member flaring outwardly from the point of connection with the nozzle to a point within the outlet opening of said windobx, a ring-shaped baflle disposed in superimposed spaced relationship with said ring member and flaring outwardly from a point adjacent the outlet of said nozzle to a point within the outlet opening of said windbox, said ring member and said battle defining therebetween an elongated annular combustion air passageway having a long radius curvature extending from and communicating with the interior of said windbox to receive combustion air from the latter and terminating adjacent the outlet of said nozzle to discharge combustion air around the nozzle outlet, and means for pivotally moving the baflle about a point approximately located in the plane of the injector nozzle outlet and along the axis of the nozzle relative to said ring member and nozzle to obliquely position the axis of said baffle relative to the axes of the latter thereby varying the direction of the combustion air discharged and controlling the direction of the burner flame.

5. A burner assembly, comprising a windbox having a combustion air inlet and outlet opening, a fuel injector nozzle having a longitudinal axis, an inlet to receive fuel and an outlet to discharge said fuel for combustion, said nozzle being disposed with a portion thereof extending through the outlet of said windbox with the outlet of said nozzle being outside of said windbox, a bell-shaped ring member disposed over and in coaxial relationship with the injector nozzle, said bell-shaped ring member being connected at the smaller diameter end to said nozzle at a point adjacent the outlet of the latter and extending in a diretcion away from the outlet of the nozzle throught the outlet opening of the windbox to a point within the windbox, a second bell-shaped ring member of larger dimensions than said first-mentioned ring member disposed in a substantially coextensive superimposed coaxial relationship with said first-mentioned ring member, said second bell-shaped ring member extending from the smaller diameter end thereof from a point adjacent the outlet of said nozzle through the inlet of said windbox to a point within said windbox, means for supporting the second bell-shaped ring member in spaced relationship to said first-mentioned bell-shaped ring member and said nozzle whereby an elongated annular combustion air passageway having a long radius curvature is defined between the bell-shaped ring members, said combustion air passageway communicating with the interior of the windbox to receive combustion air and terminating adjacent the outlet of the nozzle, and adjusting means for pivotally moving said second bell-shaped ring member about a point approximately located in the plme of the injector nozzle outlet and along the axis of the nozzle relative to said first mentioned bell-shaped ring member and the nozzle to obliquely position the axis of the second bellshaped ring member relative to the axes of the latter thereby varying the direction of the combustion air dis charged and controlling the direction of the burner flame.

6. The apparatus of claim wherein the support means comprises a plurality of four equally spaced arms which are secured to the second bell-shaped ring member and extend radially therefrom and wherein adjusting means comprises a rod for each of said arms, each rod being connected to the distal end portion of an arm, and each of said rods being mounted for axial movement to effect tilting movement in any plane of the second bell-shaped ring member relative to said first mentioned bell-shaped ring member.

7. A pulverized fuel burner comprising a windbox having an inlet for receiving secondary air and an outlet, a pulverized fuel injector assembly having a longitudinal axis, an involute portion and a discharge nozzle portion, said involute portion being connected to receive a mixture of primary air and pulverized fuel and connected to said discharge nozzle portion to pass said mixture of primary air and pulverized fuel to said nozzle for discharge, said fuel injector assembly being disposed with the involute portion within the windbox and the discharge nozzle projecting through the outlet of said windbox, a ring member having an open end portion adapted to receive therethrough said discharge nozzle and an opposite open end portion of substantially larger dimension than said first mentioned open end portion, said ring member being dis posed over said discharge nozzle of said pulverized fuel injector assembly and secured at the smaller open end portion to said discharge nozzle adjacent the outlet thereof and with the larger open end portion projecting into the interior of the windbox, a baflie means of substantially the same configuration as said ring member and of larger dimensions than the latter being disposed in a substantially coextensive superimposed spaced relationship with said ring member to define with the latter an elongated annular secondary air passageway, said baflie means and said ring member being formed so that the annular secondary air passageway has a long radius curvature, said passageway communicating at one end with the interior of said windbox to receive secondary air therefrom and terminating at the opposite end adjacent the discharge end of said nozzle, means for tilting said baflie about a point approximately located in the plane of the discharge nozzle outlet and along the axis of the nozzle relative to said ring member to vary the direction of the combustion air flow discharged from said air passageway with respect to the longitudinal axis of said burner nozzle to thereby controllably vary the direction of the flame produced by the combustion of the fuel discharged from said burner nozzle.

8. In combination with a furnace wall having a burner port therein, a burner disposed adjacent the outer surface of said furnace wall comprising a windbox having an inlet to receive combustion air and an outlet, a fuel injector nozzle having a longitudinal axis, an inlet to receive fuel and an outlet to discharge fuel for combustion, said nozzle being disposed with a portion thereof extending through the outlet of said windbox and terminating adjacent the burner port to discharge fuel into the latter, an open-ended bell-shaped member disposed over and in coaxial realtionship with the injector nozzle, said bell-shaped member being connected at the smaller diameter end to said nozzle at a point adjacent the outlet of said nozzle, and extending in a direction away from the nozzle outlet through the outlet opening of the windbox to a point within the windbox, a second open-ended bell-shaped member of larger dimensions than said first-mentioned bell-shaped member disposed in superimposed, coaxial relationship with said first-mentioned bell-shaped member and with the smaller diameter end portion disposed in the burner port in sealing contact therewith but arranged for pivotal movement relative to the axis of the burner port, said second bell-shaped member extending from the burner port through the outlet of said windbox to a point within said windbox, means for supporting said second bell-shaped member in spaced relationship to said firstmentioned bell-shaped member so that an elongated annular combustion air passageway is defined between the two bell-shaped members, the wall of each of said bellshaped members having a long radius curvature so that said annular passageway has a long radius curvature, said passageway communicating at the large circumference end with the interior of the windbox to receive combustion air from the flatter and at the opposite small circumference end communicating with the burner port to discharge combustion air therein adjacent the outlet of the injector burner nozzle, and other means for pivotally moving said second bell-shaped member about a point approximately located in the plane of the injector nozzle outlet and along the axis of the nozzle relative to said first-mentioned bell-shaped member and the injection nozzle to obliquely position the axis of said second member relative to the axes of the latter thereby varying the direction of the combustion air discharged and controlling the direction of the burner flame.

9. The apparatus of claim 8 wherein a plurality of spaced vanes are disposed in said annular combustion air passageway to impart rotary motion to the combustion air flowing through said air passageway.

10. The apparatus of claim 8 wherein said first-mentioned means comprises a plurality of spaced arms radially extending from said second bellshaped member and said other means comprises a plurality of rods mounted on said windbox for axial movement, tone rod connected at one end to an arm whereby relative axial movement of said rods effects through said arms movement of said second bell-shaped member relative to said first mentioned bell-shaped member.

11. In combination with a furnace wall having a burner port therein, a pulverized fuel burner comprising a windbox having an inlet to receive secondary air and an outlet adjacent said burner port, a burner nozzle having a longi- 1 l tudinal axis, an inlet to receive a mixture of pulverized fuel and primary air and an outlet to discharge said fuel and air mixture, said burner nozzle being disposed to project through the windbox outlet toward said burner port, a ring member disposed around said nozzle and connected to said nozzle adjacent the outlet of the latter, said ring member extending from the point of connection with the nozzle outwardly from the nozzle and into the windbox through said outlet of the windbox, a ring-shaped bathe of substantially the same configuration as said ring member and of larger dimensions than the latter being disposed in superimposed spaced relationship with the ring member and extending from a point adjacent said nozzle outlet into said windbox, the wall of each of said ring-shaped baffie and ring member having a long radius curvature so that an elongated annular combustion air passageway hving a long radius curvature is defined between the Walls of said ring-shaped bathe and ring memher, said passageway being in communication at the large circumference end with the interior of said windbox to receive secondary air therefrom and at the opposite small circumference end communicating with the area adjacent the outlet of said nozzle to discharge secondary air peripherally of said nozzle outlet, and means for tilting the ring-shaped baffle about a point approximately located in the plane of the burner nozzle outlet and along the axis of the nozzle relative to said ring member to vary the direction of the secondary air flow discharged from said annular secondary air passageway with respect to the longitudinal axis of the burner nozzle to thereby controllably vary the direction of the flame produced by the combustion of fuel discharged from the burner nozzle.

References Cited in the file of this patent UNITED STATES PATENTS 1,052,430 Lidstone Feb. 4, 1913 1,436,823 Purnell Nov. 28, 1922 1,976,208 Agthe et al. Oct. 9, 1934 2,229,068 Frisch Jan. 21, 1941 2,395,276 Jordan Feb. 19, 1946 FOREIGN PATENTS 190,146 Great Britain July 19, 1923 207,242 Great Britain NOV. 19, 1923 311,905 Great Britain May 23, 1929 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3, 143,089 August 4, 1964 Gilbert C. Whitney, J12, et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent shodd read as corrected below.

In the heading to the drawings, Sheets 1 to 4, line 2 thereof, and in the heading to the printed specification, line 2, title of invention, :for "FULL BURNER ASSEMBLY", each occurrence, read FUEL BURNER ASSEMBLY Signed and sealed thisf20th day of April 1965.

(SEAL) Attest:

ERNEST w. SWIDER' EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims

1. A FUEL BURNER ASSEMBLY COMPRISING, A BURNER NOZZLE HAVING A LONGITUDINAL AXIS CONNECTED TO RECEIVE FUEL FROM A SOURCE THEREOF AND HAVING AN OUTLET TO DISCHARGE THE SAME FOR COMBUSTION, A SOURCE OF COMBUSTION AIR UNDER PRESSURE, A BAFFLE ARRANGEMENT INCLUDING AT LEAST ONE TUBULAR MEMBER ENCOMPASSING THE BURNER NOZZLE AND COAXIAL THEREWITH ARRANGED TO DEFINE WITH THE NOZZLE AN ELONGATED ANNULAR PASSAGEWAY OF DIMINISHING CIRCUMFERENCE, SAID PASSAGEWAY EXTENDING FROM A LARGE CIRCUMFERENCE END IN COMMUNICATION WITH SAID SOURCE OF COMBUSTION AIR TO RECEIVE COMBUSTION AIR AND TERMINATING AT A SMALL CIRCUMFERENCE END IN COMMUNICATION WITH THE DISCHARGE END OF SAID BURNER NOZZLE TO DISCHARGE COMBUSTION AIR ADJACENT SAID BURNER NOZZLE OUTLET, SAID MEMBER BEING PIVOTALLY ADJUSTABLE ABOUT A POINT APPROXIMATELY LOCATED IN THE PLANE OF THE BURNER NOZZLE OUTLET AND ALONG THE AXIS OF THE NOZZLE TO POSITION THE AXIS OF SAID MEMBER AT AN ANGLE RELATIVE TO THE LONGITUDINAL AXIS OF THE BURNER NOZZLE TO VARY THE DIRECTION OF THE COMBUSTION AIR DISCHARGED AND