US1912876A - Burner construction - Google Patents

Description

June 6, 1933. E. T`. WARNER BURNER CONSTRUCTION 2 Sheets-Sheet l` Filed Aug. 29 1927 gimme@ Edgar T 02m/2er June 6, 1933. E. T. WARNER- BURNER CONSTRUCTION Filed Aug. 29, 1927 2 Sheets-Sheet 2 3mm@ Edgar TZZ/mwer 3&1:

Patented June 6, 1933 UNITED STATES PATENT OFFICE EDG-AR T. WARNER, OF SEATTLE, WASHINGTON, ASSIGNOR, BY MESNE ASSIGNMENTS, TO HENRY M. BROOKS, OF NEW YORK, N. Y., WILLIAM TUDOR GARDINER, OF AUGUSTA, MAINE, AND RICHARD KINGSL-EY HAWES, 0F FALL RIVER, MASSACHU- SETTS, AS TRUSTEES L BURNER CONSTRUCTION Application led August 29, 1927. Serial No. 216,060.

- My invention relates to burners for automatic coal stokers, and is particularly designed for such stokers as arev shown in my copending application for patent on a coke breaker, Serial Number 203,972, filed July 7,

, 1927, Patent No. 1,825,432, and in applications for patent filed in the name of Adolph Ousdahl, Serial Number 8,294, Patent No. 1,785,456, and Serial Number 8,295, filed F ebruar 10, 1925, Patent No. 1,886,577.

One object of the present invention is to provide a burner wherein the various' air holes can be cast with certainty and cheaply. A further object. is the provision of such a burner wherein the air holes are so formed that the air is directed into the mass of burning fuel substantially horizontally, so that it will penetrate the mass and then rise through it, thus permeating the entire mass to a degree not possible unless the air holes are properly directed.

A further object is the provision of such a burner, so formed that it may be inserted through an ordinary fire door of a furnace, and assembled without difficulty within the furnace fire chamber. Y

A further object isV the formation in such a burner of a number of rings all adapted to be connected together and to outline a burner and an airchamber surrounding the same.

Other objects, and in particular Vthose which relate more especially to the mechanical structure of the device, will become apparent as this description progresses.

My invention comprises the novel parts and the novel combination and arrangement thereof, shown in the accompanying drawings, described in the specification, and particularly defined by the claims terminating the same.

In the accompanying drawings, I have shown my invention in a form now preferred by me. t

Figure 1 is, in general, an axial section through the burner pot and burner of an automatic coal stoker, a part of the burner being shown in elevation.

'Figure 2 is a plan view of the same, with parts broken away to show the interior construction.

Figure 3 is a detail side elevation at right y a coal conduit 90,.within which a feed screw v 9 advances coal into a burner pot 91, and that it is common also to provide an air conduit 92 delivering air into an 'air chamber 93, surrounding the pot 91, from whence it passes into the burner. Various arrangements of these elements may be employed, and, broadly, they form no part of the present invention, except in the relation they bear to the burner. However, for the sake of clearness, I will point out that the burner pot casing 94 includes the pot 91 as an integral cast portion thereof, and that it is provided with ledges 95 and 96 to receive portions of the burner. I have also shown the burner pot casing 94 as supported at 97 upon la base casting 98. This casting also supports an ash ring 99 and a rotative member or plate 80 carrying ash sweepers 81. These cooperate with an aperture 82 in an ash conduit 83 within which an ash feed screw 8 rotates to remove the ashes. This is all described in the copending applications on the coke breaker, Serial Number 203,972', and on the ash ring filed simultaneously herewith.

It has been found that if the burner is cast as an integral piece, it requires coring to form the air holes through it, and frequently these are imperfectly cast, with the result that a high percentage of castings have to be discarded, greatly increasing the cost of these burners. Furthermore, it is extremely difficult to core these holes so that they are properly directed and of good size. I have, therefore, formed the burner of a plurality of rings, generally designated by the numeral 1 and distinguished by letters, as the rings 1a, 1b, 1o and 1d. It will be understood that as many rings as are found necessary may bel employed. Each of these rings is provided with a substantially horizontal upper surface and is serrated or provided with projections at its bottom edge, so that when fitted on the ring below, with the projections, resting against the horizontal surface of the respectively adjacent ring, air holes 10 are formed. These serrations or projections, which extend approximately parallel with the axis of the burner or grate, can be cast with little difficulty and with the certainty that they will be properly formed, and the entire ring can be cast on a poundage basis of cost. Moreover, it is easy, when casting these serrations, as distinguished from a coring operation, to cast them with horizontal or perhaps slightly inclined surfaces, as indicated at 11 in Figure 1, whereby the air entering from the chamber 93 is directed horizontally, or even slightly downwardly, into the mass of fuel within the burner. This tendency is further assisted by reason of the fact that the rings are each formed with a slightly upstanding circumferential rib 12, i. e., an annular rib or flange lprojecting upwardly from the more or less horizontal portion of the ring, which aids in keeping ashes and dust from finding their way back through the air holes into the air chamber 93, and, which, extending approximately parallel with the axis of the rings and grate or burner, from adjacent one edge of the ring from which it projects and across a portion of the adjacent ring (cooperating with an annular depression 13), not only serves to hold the rings in proper relationship to one another, preventing sidewise displacement but also serves, as shown in Figure 1, to assist theupper surface 11 in directing the air slightly downwardly into the mass of fuel. It will be understood that the tendency of this air, or the gas formed by combustion, as it becomes heated, is to rise, and this initial downward impulse merely tends to counteract the upwardtendency until the air has penetrated the mass sufficiently.

The lowermost ring 1a is supported upon `a ring 2, which has a circumferential rib 20 adapted to seat upon the ledge 95 of the pot 91 to seal this opening and to assist in supporting the burner, and forming a smooth continuation of the burner pot. Furnace cement may be used at this joint, if desired, to complete vthe seal. This ring 2 is likewise provided with a circumferential rib 12. i

To complete the burner, there is secured to the outwardly-extending-flange-portionV of the uppermost ring 1d an outer casing or upwardly and outwardly Haring collar 4 which is spaced from the various rings and extends downward outside thereof, so that it forms in conjunction with these rings the upper portion of an air chamber 93. This collar 4 has dogs 47 (Fig. 3), hereafter 1nentioned again, juxtaposed to the upper edge 94 of the casing 94 and the lower edge 42 of the collar 4 rests upon the ledge 96 of the casing 94. Furnace cement may be used at this latter point, if desired, to complete the sealing. The parts 1d and 4 are suitably secured together at their outwardly flaring portions, as, for example, by the bolts 40.

For convenience in transporting and assembling the device, it is preferable that the complete burner, comprising the several parts 2, la, lo, 10, 1d, and 4, be assembled in two sectional units. Thus the rings 1a and l?) may be clamped between the ring 1c and the ring 2 by some such means as the clamping bolts 3, provided with heads 30 and nuts 31, which pass through apertured ears 14 in the ring lc and are received in slots 22 in ears 2l projecting from the ring 2. Thus an inner sectional unit is formed of the ring 2 and the rings 1a, 1b and 1c, all of which are clamped together. The outer sectional unit is formed of the uppermost ring 1d and the collar 4 secured thereto by the bolts 40. In this connection it should be noted that the collar 4 should be of sufiicient diameter to pass over the innermost section, when this is assembled and fitted on the ledge 95. It should be noted also, as seen in Figure 1, that the heads 30 of the clamping bolts 3 are so arranged that they are covered by the serrations of the ring 1d, so that when the outer section is fitted over the inner section, the heads of the bolts are protected from the direct heat. To permit this arrangement the ring 1c is provided with recesses 15 within which the heads 30 of the bolts 3 are received.

Some furnaces will have fire doors too small to permit the insertion of the complete ring 1d and collar 4. To permit their ready insertion, they may be divided into two or more equal parts, or segments, as indicated by the slit at 44, both the collar 4 and ring 1d being divided along the same line. A clamping bolt 45 passing through ears 46 in the two segments serves to clamp the halves of this assembly together. By removing the bolts 45, each half may be inserted independently of the other half, and then bolted up inside of the furnace.

As the coal is moving upwardly continuously over the surface of the burner, there may be some tendency to lift the burner from its seat, and to resist this I have provided means for securing it firmly to the casing 94. Thus one or several dogs 5 secured at the upper edge of the casing 94 are positioned to engage similar dogs 47 which may be cast in the ring 4. Their meeting surfaces may be inclined to mutually wedge each other in place, and in this way they serve to secure the entire burner securely upon the casing 94, for the inner sectional unit cannot be raised unless the ring 1d is first raised, and this is held in position by the engagement of the dogs 5 and 47. This construction also serves to hold the several parts in proper position when first assembled, while the furnace cement is setting.

It will be noted that in addition to the horizontally directed holes 10, the uppermost ring 1d is provided with vertically directed apertures 19 close to its periphery. These apertures 19 supply air for combustion, in addition to that supplied through the apertures 10, but primarily it is their purpose to keep the ashes cool and thus to prevent the formation of clinkers. Clinkers are formed by the fusion under heat of ashes. Hence, if these ashes are kept cool, clinkers will not form. Thus these apertures 19 supply air to keep the ashes cool and to aid .in the final combustion of the coal, so that the coal about the edges of the mass is consumed just prior to its being pushed over the edge of the burner.

It will be noted in Figures 1 and 2 that the burner pot 91 has its wall opposite the opening leading to the coal conduit bulged to provide a boss 91. This boss 91 is provided for the purpose of receiving the axial thrust of the coal as it is introduced into the pot through the medium of the feed screw 9, and to divide it so that it will be distributed more evenly throughout the entire burner pot than would be the case were the wall of the pot a smooth curve at this point corresponding to the curve of the other walls. This boss, then, is in the nature of a plow share and divides and turns the column of coal and distributes it throughout the pot and burner, and this has been found of .great value in obtaining proper distribution of coal and its proper and even combustion.

It should be noted in this connection that this boss will function in a burner pot wherein the burner is a single unit, or even formed integral with the burner pot.

What I claim as my invention 1s 1. In a stoker for solid fuel, the combina'- tion of an annular grate, and means provlding an annular air chamber underneath the grate from which air to support combustionon the grate is supplied, the annular grate including a plurality of cooperating superposed rings of which'an upper ring has a l plurality' of downwardly extending projections having ring-supporting engagement with the adjacent lower ring, and said lower ring has a substantially horizontal circular portion and a circular flange rising from said substantially horizontal portion in ringcentering cooperation with said projections.

2. In a Stoker for solid fuel, an outwardly and upwardly flaring annular grate, and means providing an annular chamber underneath the grate through which air for combustion of the fuel is provided, said grate including a plurality of superposed rings each of which includes a circular upwardly extending flange on one side and a plurality of downwardly extending projections on the other side for ring-supporting engagement with the adjacent lower ring, and each` said circular flange of a lower ring extending upwardly beyond the lowest ends of said projections of the ring immediately above it.

3. In a Stoker for solid fuel, an outwardly and upwardly flaring annular grate, and means for providing an air chamber surrounding and underneath the grate through which air for combustion of the fuel is fed, said grate including a plurality of superposed rings each of which is provided with a circular upwardly-projecting flange on its upper side adjacent its outer edge and a plurality of downwardly-projecting ringsupporting projections on its lower side, said projections of leach of said rings extending v downwardly below the top of the circular upwardly-projecting flange of the ring below it and inside said flange.

, 4. In a Stoker for burning solid fuel, an upwardly and outwardly flaring grate terminating at the top in an outwardly extending flange, means providing an upwardly extending wall to partly enclose an air chamber for combustion air surrounding the grate, and an upwardly and outwardly flaring collar terminating at its top in an outwardly extending flange located below and in contact with said flange of the grate, the lower partv of said collar cooperating with said upwardly extending wall to complete" the closure of said air chamber, and means engaging the grate and collar at their outwardly flaring portions to fasten the same together.

5. An annular grate for solid fuel stokers including an upper ring and a lower ring of which one ring includes a plurality of projections engaging the other ring to support the upper ring on the lower ring and to provide passageways between the rings for the air to support combustion of the fuel on the grate, and of which two rings one ring has an annular iange extending approximately co-axially of the other ring, across a portion of said other ring, preventing sidewise displacement of one of said rings from the other.

6. In a Stoker for solid fuel, an outwardly and upwardly flaring annular grate, means providing a chamber outside and underneath they grate through which air for combustion of the fuel is supplied, and means foi` feeding fuel upwardly through said annular grate, the annular grate including a plurality of cooperating superposed rings, with projections between each two adjacent rings of said plurality to provide passageways for the combustion air leading from said chamber to the fuel on the grate, and said rings having flanges projecting approximately coaxially of the grate, and respectively across a portion of an adjacent ring, preventing sidewise displacement of the rings one from another.

7. An outwardly and upwardly flaring annular grate, for a solid fuel Stoker, including4 a plurality of cooperating superposed rings each of which includes a plurality of projections extending approximately parallel With the aXis of the grate and each of which has a substantially horizontal surface, the projections of each of said rings engaging the substantially horizontal surface of the adjacent ring to support each upper ring on the ring below it and provide passageways between the rings for the air to support oombustion of the fuel on the grate, and-each of said rings having an annular flange extending approximately cio-axially of the grate, across a portion of the respectively adjacent ring7 preventing sideWise displacement of said rings one from another.

8. The subject matter of claim 7, characterized by the fact that said annular flanges are located adjacent edges of the rings.

Signed at Seattle, King County, Washington, this 24th day of August, 1927.

EDGAR T. WARNER.

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