US2075433A - Fire box - Google Patents

Description

March 30, 1937. R. c. ElsENT RAGE 2,075,433

FIRE BOX Filed March 23, 1935 INVENTOR.

l aflkenfragei;

A TTORNEY.

Patented Mar. 30, 1937 FIRE BOX Russell cfEisentrag er, Philadelphia, Pa., assignor,

by mesne assignments, of one-half to The Lite- Cast Corporation, Philadelphia, Pa., 1!. corporation of Pennsylvania Application March 23, 1935, Serial No. 12,643

2 Claims.

My invention relates to furnaces and relatesparticularly to a furnace lining used with an' oil burner.

Oil burners have been placed in furnaces which have been constructed to burn coal for the generation of heat. It is known that an oil burner flame is big, intensely hot,'and fast burning, and it needs more space in which to burn than a coal flame does. An oil flame subjects a boiler or furnace to terrific strain, it comes forth with intense heat, and then does the same thing all over again dozens of times a day. The oil must be properly atomized, and air is added for complete combustion.

Heretofore, it has been observed that when an oil burner flame is off and the fire box is cool,

it requires five to ten minutes after the flame is formed before the fuel oil is properly consumed for the greatest efiic'iency; during this interval of time, the fuel oil is incompletely consumed. For proper consumption of the oil fuel, the furnace lining must be properly heated, and for proper heating, the furnace lining must be correctly shaped to provide for the proper reflection of the heat waves which emanate from the heated refractory lining.

Since the nozzles of diiferent oil burners eject the flame at an angle of 60 to 80, the fire box should be arranged to accommodate the angularity hereinbefore set forth. But the fire box.

or combustion chamber should be shaped so that the flame will not wipe along the refractory, and the flame should be close to the top of the fire box in order to prevent any dead air spaces which set up a cooling action.

The customary manner of constructing fire boxes has been to build the fire box of fire-brick which is generally 4% inches in width. The quantity of bricks taken along by the workmen in the ordinary installation of an oil burner is governed by the workmens estimate of the number of bricks that should be used when they arrive on the job. However, it may be necessary to alter the shape of the fire box. Withthe material at hand, they are unable to alter the fire box with the result that many fire boxes are improperly shaped. Since the shape of the fire box does not conform to the shape of the flame, the mostefllcacious consumption of fuel is not brought about.

It is, therefore, an object of my invention to construct a fire box which may be arranged to its theoretically correct shape in the furnace without the addition of any parts.

It is another object of my invention to construct a fire box which maybe used in furnaces of various sizes.

It is another object of my invention to construct a fire box which will offer a heat resistance to the flame so that the maximum heating efiiciency will be obtained.

It is another object of my invention to provide a fire box of refractory material which will be of theoretically correct shape for the most eflicient consumption of fuel.

It is another object of my invention to construct a fire box whichmay be rapidly placed in its correct position'in the'furnace, and quickly and readily removed for repairs or renewal when necessary.

It is another object of my invention to construct a flre box which will deflect the intensely hot flame so that the flame will not directly impinge on the side wall of the furnace and therefore will prevent deterioration of the furnace side wall.

It is another object of my invention to construct a fire box that may be packed in a single container together with all the complementary materials that are necessary to the assemblage of a flre box, the elements comprising the fire box being of standardized construction and di-. mensions, so that the same elements may be used for difierent sizes and shapes of furnaces.

Other objects of my invention are to provide an improved device of the character described of simple and economical construction, that possesses a maximum amount of serviceability and of strength.

With the above and related objects in view, my invention consists in the details of construction and combination of parts, that will be hereinafter fully described and the description will be morereadily understood when it is read in conjunction with the accompanying drawing in which: v

Fig. 1 is a view of my invention embodied in an oil burning furnace.

Fig. 2 is a perspective view of my fire box 0 combustion chamber.

Fig. 3 is a plan view of my invention.

Fig. 4 is a plan view of my invention wherein the parts .have been assembled for a. furnace which requires a different area and a different shape of fire-box than the area and shape shown in Fi 3. v

Fig. 5 is a plan view of the fire-box wherein ous fire box of a different area and shape than the fire boxes shown in Figs. 3 and 4.

Fig. 6 is a perspective view of a modified construction of one of the fire chamber forms or segments showing parallel grooves located in the same plane adjacent the top of the segment.

Fig. 7 is a fragmentary sectional view of the vertically extending wall, with the wall having notches therein so that the poured floor will fill 10 the notches whereby the floor and wall will be interlocked.

Referring now in greater detail to the drawing I disclose in Fig. 1 a furnace, generally designated as A, together with a pressure or gun type of oil burner, generally designated as B, and a fire box or combustion chamber, generally designated as C. The fire box embodying my invention is comprised of a plurality of separable elements which may be placed adjacent one another to form the wall of a combustion chamber for an oil burner. The fire box must be adjustable since different manufacturers of oil burners construct the nozzles to eject the oil at difiering spreadings of the spray, that is to say, some gun or pressure type of oil burners spray the oil over an angle of approximately 80, and other manufactured gun type of oil burners spray the oil over an angle of approximately 60, which accounts for the shape of the fire boxes, illustrated in Figs. 3 to 5, the shape illustrated in Fig. 5, of course, being for Wide angle of spray.

A fire box section, generally designated as D, comprised of refractory material serves as a portion of the wall of the fire box 0. The section D is a unit formed like a structural obtuse angle placed with vertex edge It vertical, the front wall I0 and side wall l8 subtending the obtuse angle. Another fire box section, generally designated as E, is similarly formed and is complemental to section D abutting it along edge M.

A tapered circular opening is centered in the abutting front faces of sections D and E. From an inspection of Fig. 2 it will be seen that dihedral section D is for the left-hand front corner of the fire box. and dihedral section E is for the other front corner of the fire box.

Two segmental arcuate sections or segments, generally designated as F and G, when placed to- FO gether form a semi-circle, but it will be seen in Fig. 4 that the two sections F and G may be shifted to form a continuous wall which is greater than a semi-circle. In Fig. 5 the two sections F and G have been arranged end-to-end to form an 55 arcuate section which is less than a semi-circle. Each section is comprised of refractory material and is similarly constructed; the section G has a curved bounding wall 20 and vertically extending straight edges 2|, 23. The section F has a curved bounding wall 20F and vertically extending straight edges 21F, 23F.

As has already been described in the introduction of this specification, the purpose of altering the area of the fire box is to provide a combustion 65 chamber wherein the fuel may be most economically burned necessitating the various shapes illustrated in Figs. 3, 4, and 5.

On the upper edge of the semi-circular elements F and G is placed a fiat segmental section 70 or horizontal baiile, generally designated as H,

which is adapted to have its arcuate edge 22 placed adjacent the inner wall 24 of the furnace so that the intense flame, which is shot forth by the pressure type of oil burner B, does not lick or 75 contact the furnace wall but is deflected back toward the central area over the straight edge 25. The fire box should not have the flame impinge directly on its walls, but they should be sufiiciently removed so that the reflected heat will completely consume the oil. The baflie H prevents the rapid deterioration of the furnace wall which would result if the flame were allowed to impinge upon the furnace wall. Thus, the baflle H permits the flame to approach close to the inner wall 24 of the furnace A, but deflects it sufiiciently to prevent direct contact with the furnace wall.

When the fire box is placed in the furnace, it

is formed in the furnace, and then a floor, generally designated as J, of heat insulating material is poured. The pouring of the floor makes it very easy to have a properly shaped fire box; and when cement is placed between the junction of the abutting sections, a very rigid and sturdy fire box is completed.

A semi-circular opening is formed in the front walls of the sections D and E when the vertically extending edges I2 are placed adjacent one another.

C so that the flame is projected interiorly of the fire box chamber.

The wall l2 defining the tapered opening may be filed or scraped with a suitable instrument adjacent its smallest diameter whenever the opening must be increased to accommodate a nozzle of a larger diameter than the opening. Since the wall itself tapers it is apparent that a less amount of material need be removed when the opening defined must be increased than would be the case if the wall were of a constant diameter.

Domestic heating furnaces are constructed for a predetermined heating capacity and, different furnace manufacturers construct their furnaces of different shapes for the same capacity. The parts comprising my fire-box need only be constructed of one size in order to fit most furnaces of the same capacity, thereby effecting a great saving in time, labor, and convenience of installation.

It is only necessary for the manufacturer to pack the knocked-down portions of the fire boxes in a casing together with a considerable quantity of cement so the mechanic in going to a new installation merely needs to take the knocked-down assemblage and vary it in the furnace to the requisite shape irrespective of whether the furnace is of a large size or of a small size.

The shape of the fire-box should only be varied from its correct theoretical shape when the theoretically correct shape cannot be employed.

It is within the scope of my invention to place horizontally extending grooves 30, 30, well il lustrated in Fig. 6, in the same plane on the inner and outer face of each segment so that the upper horizontal portion of each segment above the ridge may be easily and clearly cut-ofi in the event it is desired so to do. The grooves 30, 30 located adjacent the upper edge of the segment or section, prevents cracking of the entire section of the wall when the upper portion of the segment or section is to be chipped off, since the decreased thickness .of the segment between the grooves makes the segment weaker at that point.

In some furnace installations it may be advisable to reduce greatly the size of the fire chamber in order to provide the most efficient combustion space. In such cases it may be necessary The tapered opening permits a nozzle 26 of the oil burner B to enter the fire box chamber to place asbestos or other heat resisting material between the outside wall of the fire chamber and the inside wall of the fumace.

The thickness of the fire-box wall is approximately 1% inches, and I have found that this decreased thickness when compared with the thickness of ordinary fire brick, which is 4 inches, enables me to build within a comparatively small furnace, a larger combustion chamher than could be made with fire-brick.

In Fig. 7 I show a modified construction of a chamber wall K having two parallel V-shaped notches or grooves 40 therein. Each notch or groove receives a portion of the poured floor J so that a firmer interlock exists between the wall and the floor. The notch may be continuous or it may be broken in each segment comprising the fire-box.

It is to be observed that the combustion chamher presents a continuous inner wallirrespective of the shape of the chamber.

Although'I have disclosed the abutting edges of the various segments as having flat surfaces,

these surfaces may be of any desired shape,

which will permit alignment of the segments.

Although my invention has been described in considerable detail, such description is intended as illustrative rather than limiting, as the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

I claim as my invention:-

1. A combustion chamber comprising a pair of vertically extending insulating refractory sections; each section comprising a flat wall and a wall angularly disposed thereto, and a pair of vertically extending insulating refractory segments of arcuate formation, the pair of sections being placed adjacent the pair of segments to form a continuous wall defining the combustion chamber.

2. A combustion chamber comprising a pair of preformed vertically extending insulating refractory sections, each section comprising a substantially fiat front wall and a flat side wall, said side wall extending at an obtuse angle to said front wall, each of said sections having vertically extending free ends, the front flat walls of both sections having their free adjacent vertically extending ends close to one another whereby the front walls extend in substantially the same plane; and a pair of preformed arcuate insulating refractory segments, each segment having vertically extending free ends, each segment having one vertically extending end adjacent the free end of the flat side wall and the other end of the segment adjacent an end of the other segment whereby the combustion chamber will be defined by a vertically extending continuous wall.

RUSSELL C. EISEN'IRAGER.

Images