US1713566A - Furnace - Google Patents

Description

y 21, 1929- J. F. o. STRATTON 1,713,566 I FURNACE Filed Aug. 28, 1925 4 Sheets-Sheet l i May 21, 1929- J. F. o. STRATTON FURNACE 4 Sheets-Sheet 2 Filed Aug. 28, 1925 m o v MM L o fl MM NM wm @N WW MM. w 9% m M 4/ l hr 0? Q, J WW MM w v w fi/zn 5714 .41; PA, 14/

May 21, 1929. J. F. o. STRATTON FURNACE Filed Aug. 28, 1925 4 Sheets-Sheet 5 Patented May 21, 1929.

UNITED STATES" JOHN F. OJSTRATTON, or emcnoo;v rumors.

FURNACE Application filed August 28, 1925. Serial m. 52,999.

' The present invention relates to improve ments in furnaces, and has particular reference to furnaces of the type disclosed in my Patent No. 1,505,505, issued August 19, 1924.

That patent discloses a vertical jet furnace in which a blastor jet of air is directed upwardly through the throat into the combustion chamber. The blast of air agitates the fuel which is fed in at the top of the furnace, raises or holds it in suspension to secure complete combustion, and separates the combustible from the non-combustible portions, To create this blast, air under pressure is admitted to the ashpit which serves as a pressure chamber, and from there passes through a long narrow space defined by a pair of parallel intercepting members directly underlying the throat. V The intercepting membels are continuously reciprocatedin unison to shift theregion of the blast back and forth across the throat, thereby reaching all portions of the fuel and keeping them in amobile condition. The non-combustible portion of the fuel falls through the space between the intercepting members into the ash pit.

\Vhen the furnace is in operation, the walls of the throat or base are subjected to an extremely high temperature. A general object of the present invention resides in the provision of novel means adapted to cool the walls of the throat. by means of flowing air, thereby protecting the walls against injury from the heat.

Another object is to provide in a furnace of the above character a throat or fire pot, the

' walls of which have a large surface,and

which has means for directing the air to be used in the combustion of the fuel over the outer surfaces of the-walls to cool the throat.

A further object is to provide a novel air cooled throat which is constructed with a plurality of independent air passages for directing the air in separate streams uniformly over the outer surfaces of the heated walls.

i I accomplish the above objects by constructiug the throat of a plurality of sections having corrugated walls constituting the walls of the throat and having air passages for directing air in separate streams over said walls and from said throat, and an air supply chamber surrounding said throat and communicating with the inlets to said passages.

Still another object is to construct the throat of a plurality of sections which have independent s aced air discharge nozzles, which preferably consist of hollow metal castings, and which will not buckle up, crack or warp when. heated.

Ancillary objects and advantages will become apparent as the description proceeds.

In the accompanying drawings, Figure 1 is a vertical sectional view of a furnace embodying the features of my invention.

Fig. 2 is a fragmentary enlarged sectional view taken along line 2- -2 ofFig. 6.

Fig. 3 is a horizontal sectional view of the throat taken along line 33 of Fig. 1.

Fig. 4 is a plan view of the throat.

Fig. 5 is a horizontal sectional view taken along line 5--5 of Fig.1 and showing the operating mechanism.

' Fig. 6 is'a sectional view'taken along line 66 of Fig. 4.

Fig. 7 is a fr entary front view of a part of the operating mechanism.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preferred embodiment, but it is to be understood that Ido not therebyintend to limit the invention to the specific form disclosed but aim to coverall modifications and alternative conmructions falling within the irit and. scope of: the invention as expresse in the appended claims.

Referring more particularly to the drawings, while the main body of the furnace ma conform to any suitable construction, it pref erably comprises a front wall 10, a rearor bridge wall 11, and inclined front and rear bottom walls 12am} 13, respectively. The space bounded by these walls constitutes a combustion chamber 14. Fuel, such as'coal 15, may be continuously fed from a hopper 16 having a feed screw 17' through a spout 18 in a set off of the front wall into the upper part of the combustion chamber 1411' The front wall 10 is provided with=an opening 19 having a closure 20, through-which fuel may be thrown into the furnace by hand at any time. The inclined walls12 and 1.3 are lined with suitable refractory material, such as bricks or blocks and converge to the upper edges of a long narrow throat 21. The inclined walls serve to direct the coal and slag falling thereon into the throat.

Located at the lowerportion of the fur nace and bounded by four walls 22, 23, 24 and 25is an ash pit- 26 which alse serves as an air pressure chamber. Ashes maybe removed from the pit- 26 through an opening 27 in the wall 22 normally closed by the door 28.

The-throat 21. is constructed of a plurality of sections which fit closely together, and which preferably consist of blocks 29 shaped to form straight parallel side walls, and blocks 30 shaped to form curved end walls. The end blocks are preferably bolted togetherf The upper edges of the blocks 29 and 30 are curved or inclined, as indicated is preferred to a shorter depth since it subthroat, the inclined walls 12 and 13 are also brought nearer J to the expanding blast of air and to the area of combustion, thereby maintaining the fuel and slag on the walls at a higher temperature, and preventing fuel from passing along the walls beyond the range of the blast into the throat. I

The blocks 29and 30- preferably are hollow metal castings capable of withstazuling extremely high temperatures. Each side block 9 is formed with an air passage 32 having a downwardly extendingnozzle 33 opening into the ash pit26 at the lower end of the throat; The outer wall of the nozcle 33 terminates a short distance above the inner wall topermit lateral deflection of the discharged airs Surrounding theblocks'29 and 30 constituting the throat 21 is an air chamber 34 which communicates with the air passages The air chamber 34 includes, passages 35 around the end blocks 30'to connect the side spaces. In the present instance, each passage 35 is constructed of an upper wall 36, lower wall 37 and anend wall. 38. the

upper and lower walls extending up to the end blocks 30. Preferably the inner edge of the lower Wall 37 is spaced a small distance fromthe end blocks 30 to provide a narrow opening 39 adapted to permit the escape of a small amount of air. for cooling purposes. One side of the air chamber 34 is connected to an intake conduit 40 of any suitable shapepredetermined pressure therein. By constrncting the throat 21 of a plurality of holbe supported in any suitable manner, and in the present instance are mounted at opposite ends on four channel shaped columns 41, the

walls 36, 37 and 38 being rigidly secured thereto. These columns extend up from masonry columns 42 built in from the side walls 24 and 25 of the ash pit 26.

Mounted on each side of the columns 41 is one of a plurality of inwardly extending brackets 43 supporting a pair of parallel spacedtracks 44 and 45. Each track preferably comprises two closely spaced parallel inverted T-shaped beams or bars. Movably mounted on the trac'ksare a plurality of anti- ;friction n'leinbers, each of which consists of a pair of peripherally grooved sheaves 46 riding on the edges of the T-shaped beams and rigidly connected by a shaft 47. In the present instance, four anti-friction members, one on each end of each track are provided. Mounted for bodily reciprocation on the antifriction. members is a-pair of tracks'48 and 49 each of which comprises two parallel bars connected together by means of spacers 50, and engaging the peripheral grooves in the sheaves 46. The front ends of thebars of each of the tracks 48 and 49 are bent toward each other, and are connected by a pin 51 to which the rear end of'an operating link 52 is pivotally secured.

Mounted on the tracks 48 and 49 for reciprocation therewith across the front portion of the throat is an intercepting member which comprises a rectangular frame 54 having end brackets 55 rigidly secured to the tracks. A second intercepting member 58 having a similar frame 59 is mounted for re ciprocation across the rear portion of the throat 21. The frame 59 however is not rigidly secured to the tracks '48 and .49, but is provided-with end brackets 60 in which rollers or sheaves 61 are mounted. -The sheaves 61 engage the inner bars of the tracks 48. and 49 for adjustment toward and from the first mentioned frame. A plurality of grate bars 62 are mounted in the frames 54 and 59,'and are formed with side lugs 63 to provide the usual spacing.-- The intercepting members 53 and 58 are spaced apart to define a long narrow space or passage 64 serving a nozzle for directing a blast of air from the ash pit 26 into the combustion chamber 14. To provide means for adjusting the width of the formed with upstanding lugs to which the rear ends of two spaced adjusting links 66 are pivotally secured.

Two cleaning or slicing members 67 and 68 are provided for dislodging slag and other material adhering to or collecting on the intercepting members '53 and 58 respectively. The members 67 and 68 comprise a plurality of slicing grates 69, the free inner ends of which are respectively reciproeable in the front and rear sides of the throat and on the underlying grates 62 to and from the front and rear edges of the space 64, and the outer ends of which are formed with hooks 70 fitting respectively over two'horizontal shafts 71 and 72 extending along opposite sides of the throat. The front shaft 71 is mounted in the free upper ends of two spaced arms 73' pivotally mounted at their lower ends on the front brackets 43 at opposite sides of the ash pit 26. The arms 73 are 'pivotally connected near their upper ends by means of studs 74 to the rear ends of two operating links 75. The rear shaft 72 is similarly mounted on arms 76 supported by rear brackets 43 and pivotally connected by means of studs 77 to two operating links 78. The slicing grates 69 are formed with side lugs 79 to provide the usual spacing and are dimensioned to extend beyond the sides of the throat 21 in all positions of reciprocation. The ends of the intercepting members and slicingmembers also extend beyond the ends of the throat 21. The grates 62 and 69 permit small amounts of cold air to percolate through the intercepting members and slicing members to cool the latter and to cause the slag falling thereonto harden. \Vhile grates preferably are employed, it is to be understood that any other suitable means having small openings for the passage of air may be employed.

To prevent fuel or slag from being carried on the grates 69 out of the throat 21, a plurality of scraper members 80are provided. In the present instance, four scraper mam bers are provided, and each member comprises a-bar 81 extending along one half of one side and curved partially around one end of the throat 21, and a pair of spaced arms 82 pivotally secured in brackets 83 on the under side of the air chamber 34. The bars 81 rest on the grates 69 directly beneath the nozzles 33, and each bar is formed with an upstand ing' flange 84 for deflecting part of the air from the nozzle overhead outwardly over the surfaces of the grates 69. Air thus passes over and through the grates 69 to cool the latter. 7

The front ends of the links 52, 66, 75 and 78 are pivotally connected to four pairs of levers85, 86, 87 and 88 mounted on four shafts 89, 90, 91 and 92 respectively. These shaftsextendtransversely in the front of the ash pit 26, and through air tight bearings 93 in-the side wall 25 into-a chamber Mopen at the top to the atmosphere, and are jom'naled in spaced-bearing brackets 95 and 96 in opposite sides of the ash pit and in a bear ng bracket 97 in the chamber 94; The levers extend upwardly from the shafts so as to have a horizontal throw, and'are subject to adjustment as will be hereinafter described; Secured to the ends of the shafts 89, 90, 912ml 92 in the chamber 94 are four substantially horizontally disposed levers'98, 99, 100and 101 respectlvely which are pivotally connected to the lower ends of four links 102, 103, 104 and 105 respectively, extending vertically through a hole 106 in the floor 107 at the front of the furnace. The-levers 98 and 101 extend forwardly, and the leve1s99 and 100 exi porting standard 110. Each sector plate 108 is formed with an amuate slot 111 in which a bolt 112 is adjustably mounted. One end of the bolt 112 is pivotallysecured to one of the links 102, 103,104 and 105,- and the'other end is provided with a hand wheel nut 113 for clamping the bolt in adjustedposition in the slot 111. The bolt is alsoprovided with a hand lever 114 whereby it may be moved in the slot lll'when the nut 113 is loosened either to effect an adjustment or to manually operate the associated link. The plate109'is formed witha downwardly extending arm 115 which is connected through a link 116 to a crank arm 117 of a: reduction gearing 118-driven by any .mitable means (not shown). The operating mechanism herein described for the tracks'and-the grates is fully disclosed and'claimed'inmy U. S; Letters Patent No. 1,640,056, granted-"August 23, 1927. a

In operation of the furnace, crushed fuel 15 is charged into the furnace from the spout 18 in the form of a falling stream. The fuel nozzles 33 on the remote side of the threat 21'.

A small amount of air also passes through the end. openings 39-into the ash pit. In passing around the outer surfaces ofthe corrugated walls of the end blocks 29 and 30 and through the nozzles 33 and openings 39, the

air coolsgthe walls ofthe throat, therebypre- Venting overheating. Part ;of the air discharged from the nozzles 33 passes through. the spaces between the grates 62 and 69, and part is laterally deflected by the scraping members 80 to pass over the surfaces ofthe grates .69, into the ash pit 26, thereby cleaning and cooling the grates. From the ash pit, the air is forcibly discharged-in the form of a blast through the space 64: between the intercepting members 53am 58 into the combustion chamber 14. The blast of air expands and tends to hold the fuel in suspension. The course of the air is il'iQlCiltGCl in the drawings byarrows.

j The fuelis consumed while in suspension. Parts of the fuelfall on the inclined walls 12 and 13, and arc directedthereb-y into the throat 2-1. Molten slag runs down the inclined walls into the throat and onto the grates 62 and 69. .1 The slag there is caused to solidify by the relatively coldair percolating up through the spaces between and cooling the grates. The non-combustible material has a greater specific gravity than the incandescent and partially volatilized combustible material. A 'pressure is maintained in the ash pit sucht-hatthe force of theblast of air will allow the nn-c01nbustible material to fall through the space 64 into the ash pit, andv will retain the-combustible material in suspension. The width of the space 64 between .tlieiiitei'cepting members can be adjusted by adjusting the connection between the link 103 and the associated sector plate 108, and the range of-reciprocation can likewise be adjusted by adjusting the links 102 and 103 relative to the sector plates. The intercepting mcmbersligand 58, are re ciprocated to shift the region of the blast of air slowly backand forth across the throat,

' but not to the verysides of the throat. By

shifting the region of the blast of. air all parts of the fuel in the furnace are reached. The slag and fuel on the grates 62. are dislodged and moved into the blast of air by the slicing grates 69 which are reciprocated oppositely to the members Y53 and 58, therebycleaning the grates and alsoagitating the material to pernit efilClGIll] separation. The reciprocation of I K the slicing members is continued and at sufficient speed to prevent-a large mass of material from collecting on the grates. Each slicing member is moved substantially out of the throat on its outwardstroke to clean the same,

and thiscleaning is facilitated by means of the scraping members 80. The scraping members 80serve to clean the slicing grates 69. By cleaning the grates 62 and 69 efficient cooling .is-permitted. The range and extent of reciptively operated manually by meansof hand 7 levers 1 1a. V

It will be evident that I have provided a novel andvhighly efficient means for cooling the throat or fire box of a furnace by the use of air. The cooling effect obtained is uniformly distributed, and adequate under very exacting conditions.

I claim as my invention:

1. A furnace having,in combination, a combustion chamber having a throat .in the bottom thereof, a. pressure chamber below said throat, means for directing air from said pressure chamber through said throat into said combustionchamber, and means for directing incoming air in a plurality of. streams uniformlyover the outer surfaces of the walls of said throat to cool the latter.

2.1 A furnace having, in combination, a combustion chamber,a throat in the bottom of saidcoinbustion chamber, said throat being constructedof a plurality of hollow section blcclzs,,an air chambersurrounding said sectionblocks and serving to direct airthereto, and said blocks serving to direct air over the outer surfaces of the walls of said throat.

3. A furnace having, in combination, a com bustion chamber, a fire box in said combustion V chamber, the Wallsof said firebox consisting of a plurality of hollow-side sections and end sections, the side sections being. formed with air passages .'terminating in nozzles at the lower edges of said box and serving to direct air over the outer surfaces of the walls of said box, and'an air chamber surrounding said box and communicating with the inlets of said passages. r 4. A furnace having, in combination, a combustion chamber, and a fire box in the bottom of said combustion. chamber, the walls of said fire box being constructed of a plurality of hollow sections, said sections being formed with .air passages for directing air over the outer surfaces of the wall exposed to the heat in saidfirebox. e a 1.. r .5. A. furnace having, in combination, a heated chamber, the walls, of V which are formed of end sections and side sections, the endsections being formed with air passages terminating iii-nozzles at the lower end of said chamber and outside thereof and serving to direct air over the outer surfaces of the wallslof. said chambe y-and an air chamber surrounding said heated chamber and communicating with" theinlet-s. to said passages and forming passages around the ends'of said heated chamber.

6. A furnace having, in combination, a

combustion chamber having a throat in the bottom thereof, the walls of said throat comprising a plurality of hollow side sections and end sections, the side sections being formed with air passages terminating in nozzles at the :lower edges of said throat and serving todirect air over the outer surfaces of the walls of said throat, an air chamber. surrounding said throat and communicating with the inlets to said passages, a pressure chamber below said throat, said pressure chamber enveloping said throat and said air chamber, intercepting means disposed at the bottom of said throat for direct-ing a blast of air from said pressure chamber into said combustion chamber, grate means relatively movable over said intercepting means and projecting outwardly therefrom, said nozzles serving to direct incoming air downwardly through said intercepting means into said pressure chamber, and means for directing a portion of the air from said nozzles outwardly over said grate means.

7. A furnace having, in combination, a combustion chamber having a throat in the bottom thereof, the walls of said throat comprising a plurality of hollow side sections and end sections, the side sections being formed with air passages terminating in nozzles at the lower edges of said throat and serving to direct air over the outer surfaces of the Walls of said throat, an air chamber surrounding said throat and communicating with said passages, a pressure chamber below said throat, and means disposed at the bottom of said throat for directing a blast of air from said pressure chamber into said combustion chamber, said nozzles opening downwardly and outwardly to direct incoming air through and over said means into said pressure chamside blocks and end blocks, the side blocks being formed with air passages terminating at the lower edges of said throat and serving to direct air over the outer surfaces of the corrugated walls of said throat, an air chamber surrounding said throat and communicating with said passages, the lower wall of said chamber being spaced slightly from said end blocks, and means for directing a blast of air through said throat into said combustion chamber, said passages serving to discharge incoming air over said means. 7

In testimony whereof, I have hereunto affixed my signature.

JOHN F. O. STRATTON.

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