US2011344A - Furnace - Google Patents

Description

Aug. 13, 1935. O KELLY 2,011,344

FURNACE Filed Nov. 17, 1950 6 Sheets-Sheet l g aelf Aug. 13, 1935. O; KELLY 2,011,344

FURNACE Filed Nov. 1'7, 1930 6 Sheets-Sheet 2 7 17. 2 1

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Aug. 13, 1935. o. KELLY 2,011,344 I FURNACE Filed Nov. 17, 1930 6 Sheets-Sheet 3 (253/ 7 lil 22 6 k7 o 4m o% m ww 5 0. KELLY Aug. 13, 1935.

FURNACE Filed Nov. 17; 1950 s Sheets-Sheet 4 Aug. 13, 1935. Q KELLY 2,011,344

' FURNACE Filed Nov. 17, 1930 6 Sheets-Sheet 5 Aug. 13, 1935. o. KELLY 2,011,344

FURNACE Filed Nov. 17, 1950 6 SheetsfSheet 6 7 I72 7160 I 5 07": 72 {e 665 alf Patented Aug. 13, 1935 ATENT OFFICE FURNACE Orin Kelly, Columbus, Ohio Application November 17, 1930, Serial No. 496,266

6 Claims. (01. 110-109 My invention relates more particularly to furnaces of the self-stoking type. 7

One of my objects is to provide a construction of self-stoking furnace which will be highly suit able for the use of slack coal as the fuel to be burned therein, the tars in such "coal having a tendency to bake.

Another object is to provide a construction of furnace of the type above referred to, which will be highly suitable for domestic uses which re quires the feeding of the fuel in relatively small amounts and the provision of low power feeding mechanism.

Another object is to provide a construction of furnace of the type above referred to and involving as an element-thereof a plunger for feeding the coal, in which the bunching of the coal ahead of the plunger, with the consequent exertion of objectionable forces against the side walls of the trough in which the plunger operates is minimized and in which the power required for operating the plunger is reduced to the minimum.

Another objectis to provide a construction of furnace of the type above referred to by which a small and regular feed of the coal may be effected. I

Another object is to avoid the tendency of the coal when wet or dirty to pack or hang in the hopper from which the coal feeds to the feeder mechanism.

Another object is to provide a construction of furnace of the type above referred to in which not only is it possible to feed small quantities of coal and effect such feed regularly and uniformly, but it is also possible to vary the feed to feed larger or smaller quantities as desired.

Another object is to provide an effective seal against the escapeof gases and smoke from the furnace in the event of the continuation of the operation of the feeding mechanism after the hopper from which the coal is fed to the feeding mechanism becomes exhausted.

Another object is to provide for the regular and uniform feeding of small quantities of coal without danger of imposing heavy loads or stresses on the mechanism should a relatively large lump of coal be encounteredby the feeddevice.

Another object is to provide a construction of furnace whereby the fire bed is rendered selfcleaning, even with the Worst of clinker-forming coals, or as frequently happens, when tin cans, broken glass, crockery, and other non-cornbusa tible masses are thrown into the furnace,

Another object is to avoid the forcing of live coals into the ash pit by the stoking mechanism; thereby economizing in the useof fuel; and other objects are as will be manifest from the following description.

Referring to the accompanying drawings:

Figure 1 is a view in longitudinal sectional ele I vation of a furnace constructed in accordance with my invention, the section being taken on line ll of Fig. 2 and viewed in the direction of the arrow.

Figure 2 is a rear view of the furnace thefurnace being viewed from the right-hand side of Fig. 1. V f

Figure 3 is a broken sectional view of the fur nace of the preceding figures, the section being taken at the line 3-3 on Fig. 1 and viewed "in the direction of the arrows.

Figure 4 is a broken plan sectional view taken at the line 4-'-4 on Fig. 1 and viewed in the direction of the arrows. y

Figure 4 is a broken plan View of one of the reciprocatory devices for feeding thefuel through I the coking chamber.

Figure 4 is a section taken at the line l? on Fig. 4 and viewed in the direction of the arrows. Figure 5 is a broken plansectional view taken at the line 5-5 on Fig. 3 and viewed in the direction of the arrows. j 1 Figure 6 is a broken section taken at the line 6-6 on Fig. 1 and viewed in the direction of the arrows with certain parts omitted.

Figure '7 is a broken section taken at the line l--'! on Fig. land viewed in the direction of the arrows also with certain parts omitted. Figure 8 ma view in sectional elevation of a portion of the mechanism for operating the feed device; and I Figure 9, a plan section taken at the line 9- 9 on Fig. 8 and viewed in the direction of the arrow.

In the following description of the construction shown that end of the furnace into which the fuel is introduced is termed the rear end of the furnace and its opposite end the frontfend containing an inlet I! for the air to be heated and outlets I8 for the heated air.

The rear head I0, which rests at its sides on the frame I5, is provided with a horizontal partition I9 dividing the space within the head into upper and lower compartments 2D and 2!, respectively, opposite side portions of this head being alined with the side walls 22 of the member I 4, the forward wall of the head I0 at its lower portion being open as represented at 23 and the side wall of the compartment 20 containing outlets 24 for communication with a stack (not shown);

The front head I I, which also rests at its sides on the frame I5 contains a partition 25 which alines with the upper portion of the member l4 and dividesthe space within the head I I into upper and'lower compartments 25 and 21, respectively. I

The flue pipes I2 connect at their opposite ends with the interior of the upper. compartment 20. of the head I!) and the upper compartment 26. of the head 'I I, and the flue pipes I3, ar ranged at opposite sides of the furnace, connect at their opposite ends with the interiors of the lower compartment. 2I of the head I5! and the upper compartment 26 of the head II, the lower compartment 2I. of the head If! communicating at the opening23 with. the lower portion of the space within the member I4.

By the arrangement described a combustion chamber; indicated at 28 and comprising the heads II and II and the member I4,.is provided, the products of combustion generated therein passing from this chamber ,rearwardly into the lower compartment 2I of thehead I0 and thence.

upwardly, in divided streams, into the rear ends of the flue pipes I3 and forwardly in the latter into the compartment 26 of the head II from which theypass rearwardly through the flue pipes I2 into the compartment 20 of the head I3 and then discharge to the stack.

The furnace shown comprises mechanical stoking means for feeding fuel, such as for example slack coal, and fed thereto as hereinafter described to the fire-bed, these stoking means also comprising the grate portion on which the firebed is supported. I I

The combined grate-forming and stoking .mechanism shown comprises a series of stationary grate sections 29- extending entirely across, and forming the bottom of, the combustion chamber 28, these grate sections being spaced apart vertically and arranged in the formv of steps as shown.

frontend of the furnace as hereinafter described.

Interposed between adjacent ones of the stationary grate sections,29 are grate sections 30 mounted to be reciprocated lengthwise of the furnace and operating to advance the fire-bed toward the rear end of the furnace and replenishing the fire-bed with fuel. delivered thereto at the The movablegrate sections 30, together with a plunger 3|. located directly above the uppermost stationary grate section 29., are rigidly connected together by brackets 32 and 33 and rods 34., The

brackets 32 and'33 are. duplicated at opposite sides of the furnace and each of the brackets 32 provided on its underside with'a rack'3-5, these racks. meshing with. gear-segments 36. rigid on the ends of a rock-shaft 3:? having an. arm 38 pivoted at 33. toone' end of a link 40- the opposite end. of. which is pivotallyconnected to a crank pin ll.- on a disk. 42 rigid on a shaft 43 and actuated by the. mechanism hereinafter described, the disk 42 containing a series of openings 42 disposed at 2,011.344 a. I v different distances from the shaft 43 to selectively receive the pin 4| for varying the throw of the link 40. V 7

The furnace structure also comprises a plate i2I which extends across the rear end of the combustion chamber and is pivotally supported at its ends in yoke bearings I22 (one only of which is shown) extending inwardly from the side walls of the chamber 28, the plate I2I having a weight I23 extending to one side of the axis about which theplate I 2| is s'wingable. 'Located to the rear of the one of the grate sections 29 nearest the rear end of the furnace is a plate I24 which extends rearwardly beyond the rearward travel of the lowermost one of the reciprocable plate sections iifl but spaced from the rear wall of the combustion chamber 28, whereby an opening therebetween to theash pit of the furnace represented at I25 is provided; the plate I2 I and plate !24 being so relatively positioned, as shown, that the plate l2l normally inclines downward-1y in a forward direction under the action of the eccentrically disposed weight I23.

The ash pit represented at HS -preferably com I tains ash pans I26shown asarranged i-na series extending from the frontto the rear of the fur- I nace, the rear and side-walls of the-.ash-pit preferablyv being providedwith flanges I21" which overlap the rear edge of the rear. par-1f and the side edges of each pan, adjacent ones of these pans having hook shaped lips I28 whichaoverlie the adjacent edges of the adjacent pans, thereby providing means for insuring the dropping of all of the ashes intothe pans;

. The topportion of the archinember it forms the top and sides of a, coking chamber 54, the bottom of which is-fo-rmed of a. series of, alternating stationary: and-sliding sections 45 and M, respectively, which are arranged in the form of steps but reach short of the forward end of. the furnace thereby to-provide an opening i'iiat' the forward end of. thiscoking chamber through whichthe coal to be consumed in the furnace and preliminarily heated by the heat generated in the fire-bed belowit, discharges to-the grateforming and staking mechanism above" described.

The bottom of the coking chamber contains openings therethroughthrough which. the fine particles of coal may'dropupon: the hot fire-bed below. In ,the construction shown both of the fixed plate-sections 55 are slotted as represented at 48 to form the above referred to openings in the bottom of the coking chamber;

The sections 45, each of a length substantially equal tothe width of the. coking chamber as shown in Fig. 3,, are groovedtalong their opposite edges as represented at 45 at which they are supported on ribs 5*? extending inwardly from the sides of the coking chamber, these plates being provided along their longitudinal edges with upthe sliding sections 46.

The upper one 'of the sliding sections 46 is formed of a pair of parallel bars 52 having shrouded rack portions. 53 along thei'r'undersides at their .outer ends at which they project rearwardly through. the rear wall of the casing t6, the bars 52 being connected together at'their outer ends by a yoke 5d. The inner ends of the bars 52 which extend. between. the flanges 51 are" recessed along their opposing surfaces as represented at 55 and along their upper surfaces as represented at 56, whereby they present upwardly facing seats 51 from both ends of each of which shoulders 58 on the bars 52 project inwardly. The section 46 now being described also comprises a plate member 59 which spans the space between the bars 52; The plate 59 is recessed at its opposite ends as represented at 60 at which it receives the shoulder portions 58 of the bars 52, the underside of the plate 59 at its opposite edgesbeing recessed lengthwise of the plate as represented at El at which theplate extends into the recesses 56 in the bars 52 and rests on the bottoms of these recesses.

The lower one of the sections 46 comprises parallel spaced apart bars 62 pivoted at their rear ends, as represented at 63, to depending lugs Gd on the bars 52. The forward ends of the bars 62 are recessed as explained of the bars 52 for interlockingly' supporting a plate member 65 like the plate 59, and in the manner as above described of the latter. I

It will be understood from the above description that the plates 59 and 65 are designed to be supported by, and interlocked with, the bars with which they are associated, and by merely dropping them into place; these plates being of such weight as to ensure against their displacement from interlocked relation with the bars in the operation of the feeding mechanism.

The sections 46 are thus connected together for simultaneous reciprocation to effectthe feed-= ing of the coal supplied thereto as hereinafter described, through the coking chamber 44, by

power applied to the rack-portions of the bars 521 The feed mechanism also comprises a fuelhopper B5 and a trough member 6'! located above the bars 52 and extending lengthwise of the latter and provided with a rear wall 68 containing an opening 69 and forming a continuation of the rear wall of the hoppen The opposite side walls of the trough member 61 which extends partly into the coking chamber are formed of lower wall portions all and upper outwardly-offset wall-portions H providing therebetween, substantially horizontal portions 12 forming ledges.

The bottom 13 of the hopper 66 which extends crosswise of the trough 6! and at opposite sides thereof as shown is of rounded trough-like form and extends substantially to the bottom of the trough 6?, the side walls of the latter being cut away as represented at M and the hopper-bottom cut away at the portion thereof directly above the trough 6'41 whereby the trough portions of the hopper-bottom open into the trough 61.

The feeding mechanism now being described also comprises a plunger '15 located, and reciprocable, in the trough 6'! between the side-wall portions 10 of the latter, this plunger being of substantially the same height as the wall portions 10 and shown as formed of a portion 16 of inverted U-shape in section secured at its rear end to the yoke 54. The front edge of the portion 16 terminates in a depending flange l1, and projecting forwardly therefrom is a pair of horizontally spaced prongs 15 The plunger 15 is provided for the purpose of intermittently feeding the fuel from the hopper 55 to the feed devices in the coking chamber and as a means for regulating the amount of fuel fed upon eachreciprocation of the plunger, the yoke bars 52 are provided with longitudinal series of holes 18 at which the yoke 54 may be secured to the bars 52 by the bolts 79.

The mechanism also comprises a check-gate shown as in the form of a plate pivoted at its upper end, as represented at 8|, to a stationary part of the structure, the gate 80 which inclines downwardly and forwardly being of a width substantially equal to,the width of the trough 61 between its upper wall portions H and bearing at its lower, forward, edge on the ledges 72.

In the operation of the apparatus, as hereinafter described, the coal fed by the plunger passes beneath the gate 86 which latter is made of such The shaft is provided with an arm 81 rigid therewith and pivotally connected at its outer end as represented'at with the upper end of a link 39, the lower end of which is pivotally connected with a crank pin 98 on a disk 9! rigid on the shaft 43, the disk 9! containing a series of openings 92 disposed at different distances from the shaft 43 to selectively receive thepin for varying the throw of thelink 89 The trough-forming bottom of the hopper 66 is equipped with agitating means shown as in the form of a shaft 82 journalled in the ends of the trough l3 and equipped with sections 83 of relatively large, coil-springs positioned on the shaft '82 as shown so that when the latter is rotated in.

one direction the spiral sections 83 will operate to exert force on the fuel in the hopper tending to move the fuel from the ends toward trough 61.

In the arrangement shown means operatively connected with the link 89 are provided for rotating the spiral agitator in the hopper, the means shown comprising an arm 92 rigid on the shaft 85, a link 93 pivotally connected at its lower end, as represented at 9 3, to the arm 92 and at its upper end, as represented at '95, to a lever 96 journalled on the shaft 82 and provided with a pivoted pawl Ell cooperating with a ratchet-wheel 98 rigid on the shaft 82, whereby rocking movement of the lever 96 is converted into unidirectional rotary movement of the shaft 82.

It will be understood from the foregoing that rotation of the shaft d3 operates to simultaneously oscillate the gear segments 36 and 84 for reciprocating the grate-members 3B, the feedmechanism sections at, and the plunger 15 and. rotating the agitator device in the bottomof the hopper.

The mechanism for rotating the shaft 43 may be of any desirable construction. That shown is in the form of a fiuid-pressure-operated piston and cylinder mechanism represented at 99, the cylinder of which is represented at Hill, and may be of any suitable construction, it having a valve mechanism the casing of which is represented at ill! and the stem of the valve at [E32 which serves in oscillating to control the inlet of fluid pressure to the opposite ends of the cylinder Hi9 and the exhaust therefrom, for effecting reciprocation of the piston (not shown) therein which is provided with a-piston rod M53.

The piston rod 9GB is shown as carrying a member I84 of angle shape, the lower horizontal arm H35 of which is provided with a pair of H2 pivoted thereto at H3 and H4, respectively. The pawls Hi and H2 are provided for cooperation with a ratchet-wheel I I5 located within the casing m9 and fixed on the shaft 43 journalled in the sides of the casing Hi9, the ends of the shaft 43 beingprovided with the disks 42 and 9| as above set forth.

It will be understood from the foregoing that ends of the cylinder l 0!! and exhausting the spent fluid therefrom, is automatically operated at substantially the ends of the piston strokes,

through the medium of a slide-bar H6 provided with stops I I1 spaced apart and located at opposite sides o'f'an arm H8 secured to the upper end of the valve-stem IE2, coil springs H9 being interposed between the stops ll! andthe arm H8. The slide-rod H6 is also provided with spaced-apart tappets I20, the upwardly extending arm I Ma. of the member I 04 being positioned between these tappets and cooperating therewith to effect the'shifting of the rod l 65 for controlling the position of the valve mechanism, as will be readily understood. As the piston nears the limit of its movement to. the left in Fig. l the arm lll ia strikes the left-hand tappet I turning the valve stem I02 to permit actuating fluid to enter the cylinder I09 at the left-hand end thereof in Fig. 1 and, the exhaust pressure to exhaust from the opposite end of the cylinder;

" and as the piston nears the limit of its movement to the right in Fig. 1 the arm Ill la strikes the right-hand tappet I20 to open the righthand. end of the cylinder I00 to the force of fluid pressure and open the opposite end of the cylinder to exhaust.

' In the operation of the mechanism, the movement of the plunger'15 to the right in Fig. 1 permits coal to drop onto the bottom of the trough 61 in front of the flange TI of-the plunger and J- between'the prongs 15 and in its movement to the left in Fig. 1 advances in the trough fordischarge upon the feed mechanism in the coking chamber, the coal deposited in the trough from the hopper, it being understood that in the mechanism as shown, and preferably, the pusher portion H of the plunger does not move to the left in Fig. 1 beyond the lower edge of the plate 86. The coal thus pushed beyondthe inner end of the trough 6'! falls upon the upper feeder section 46 which latter in its reciprocations feeds the coal upon and along the upper section from which it discharges to the lower section 46 and is thence fed along and from the lower section 45 from which the fuel drops upon the combined grate and feed mechanism at the bottom of the combustion chamber.

It will be understood from the foregoing that in the movement of the fuel along the bottom of the coking chamber 44 the coal is subjected to the heat from the the bed on the grate at the bottom of the combustion chamber, causing the coal to become heated with the result of drying the coal and at least partially coking it, the finer particles of coal dropping through the apertures 48 and upon the hot fire bed below, and. being indried and heated condition, these finer particles readilyignite, very much the same as in the case of gas, with almost complete combustion.

The coal in passing through the coking chamber gives off more or less of the volatile matter therein which, together with air entering this chamber at the rear end thereof which becomes heated in this chambentravels, under the action of the draft in the stack, along the coking chamber tothe front end thereof and thence into the combustion chamber above the fire bed where it will be burned without waste or smoke.

The coal which isthus deliveredto the grate sections in the combustion chamber is in driedand at least partially coked condition thereby eliminating the production of smoke and ensuring practically complete combustion of the coal thereby made for permitting occasional large lumps of coal contained in the body thereof to be fed to the coking chamber without choking the opening or subjecting the mechanism to undue stresses.

The check gate also serves to ensure the forming of a coal-seal preventing the escape ofsmoke and gases into the room in which the furnace is located should the mechanism continue to operate after the hopper 66 has been emptied, in-

asmuch as there will always be a residue of coal in front of the feedportion ll of the plunger and on the top of the, latter which will not feed out and which residual body of coal, in conjunction'with the check gate 8!), closes the furnace against the escape of smoke andgas;

The provision'of the prongs i5 on the plunger 15 is of advantage as they prevent the baking and building up on the plunger of the tars in the fuel when of the low volatile kind, which baking 'or'building up seriously interferes with the regularity of feed and requires greater power for operating the feed mechanism. Furthermore, the prongs referred to operateto avoid the exerting of pressure against the side walls of the trough 51 in the feeding operation with the result of reducing the'power required for operating the feed mechanism and minimizing the bunching of the coal ahead of the plunger with the result of insuring more nearly perfect regulable feed. I

Apparatus constructed in accordance with my invention is of special value for so-called domestic use where the amount of coal required'to be fed at intervals is relatively small, the cost of such structures must be kept low, and the same be operated with the minimum of power consumption.

The agitator, the spiral sections 83 of which are preferably of spring steel, is not only of ad.- 7

vantage because of its capability of turning freely through the coal when the hopper is full, as compared with the resistance which would be afforded by a solid screw, and its capability of overcoming the tendency of the coal when wet or dirty to pack and hang, by breaking up the body of material, but also as it serves as a screw conveyor to feed the coal to the plunger when the fuel supply in the hopper is low.

By providing-the pivot plate I2| and the stationary plate portion I24 associated therewith as stated, the fire bed of the grate is caused, by the resistance offered by the plate I24, to bunch up at the rear portion of the fire bed against the plate IZl, forming a thicker bed at this point than otherwise would be produced; the pushing action of the movable grate sections 38 being horizontal and the plate i124 presenting frictional resistance to the sliding of the fire bed across it, the partially burned out coals are crowded on top of the fire bed at this point by the movement of the rearwardmost one of the grate sections 30 while the forward grate sections push the ashes, clinkers, and such other non-combustible masses, such as tin cans, broken glass, and crockery, which may have been thrown intothe furnace, againstthe plate I2l which swings rearwardly and permits the ashes, clinkers, and such masses to drop into the ash pan below; thus the fuel is entirely consumed before being dumped into the pit and fire bed is rendered self-cleaning.

The bunching of the fire bed against the plate BZI also serves to effectually seal the cleansing spaces at the ends of the plate I21 thereby aiding the draft through the grate.v

While I have illustrated and described a particular construction embodying my invention, I do not wish to be understood as intending to limit it thereto, as the same may be variously modified and altered without departing from the spirit of my invention. 7

What I claim as new, and desire to secure by Letters Patent, is:

1. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough, the upper portions of the side walls of said trough being laterally offset, a feed member reciprocable in the lower portion of said trough and operative to feed the coal in said trough, and an upwardly yieldable member extending into the upper portion of said trough normally resting I upon the shoulders of said offset and against which the coal fed by said first-named member moves, for the purpose set forth.

2. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough, the upper portions of the side walls of said trough being laterally offset, a feed member reciprocable in the lower portion of said trough and operative to feed the coal in said trough, and a check-gate for the coal fed by said member comprising a hinged plate extending in the upper portion of said trough, inclining downwardly in the direction in which the coal is fed and resting upon the shoulders of said offset.

3. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough, the upper portions of the side walls of said trough being laterally outwardly offset and presenting ledges at the opposite sides of the trough between the upper and lower edges thereof a feed member reciprocable in the lower portion of said trough and operative to feed the coal in said trough, and an upwardly yieldable member extending into the upper portion of said trough and normally bearing on said ledges and against which the coal fed by said first-named member moves, for the purpose set forth.

4. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough the upper side walls of which are laterally offset, a feed member reciprocable in the lower portion of said trough and operative to feed coal in said trough, and an upwardly yieldable member extending into the portion of said trough above said offset portions and against which the coal fed by said first named member moves and of substantially the same length as the width of the upper portion of said trough, said first-named member having spaced apart prongs extending forwardly therefrom and in the lower portion of said trough and between which the coal becomes positioned.

5. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough the upper side walls of which are laterally offset, a feed member reciprocable in the lower portion of said trough and operative tofeed coal in said trough, and an upwardly yieldable member extending into the portion of said trough above said offset portions and against which the coal fed by said first-named member moves and Y of substantially the same length as the width of the upper portion of said trough and normally resting upon the shoulders of said offsets.

6. In stoker mechanism, the combination of a container for the coal having an outlet portion, a trough the upper side walls of which are laterally offset, a feed member reciprocable in the lower portion of said trough and operative to feed coal in said trough, and an upwardly yieldable member extending into the portion of said trough 1 above said oifset portions and against which the coal fed by said first-named member moves and of substantially the same length as the width of the upper portion of said trough and normally resting upon the shoulders of said offsets, said first-named member having spaced apart prongs extending forwardly therefrom and in the lower.

portion of said trough and between which the coal becomes positioned.

ORIN KELLY.

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