US1485317A - Mechanical-stoker furnace grate - Google Patents

Description

Feb. a

S. WADAS MECHANICAL STOKER FURNACE GRA'IIE Filed Sept. 15, 1921 3 Sheets-Sheet l Feb. 2s 1924. Y 1,485,317

s. WADAS MECHANICAL STOKER FURNACE GRA'UE4 Filed Sept. l5, 1921 3 Sheets-,Sheet 2 l" l'. llllllllllllllllllllll-l lllllllnun attozmua R v .NW "Lw Nw W/ mw Feb y. 19240 S. WADAS MECHANICAL STOKER F-URNACE GRATE' Filed Sept. l5. 1921 3 Sheets-Sheet 5 useful improvements in mechanical st Patented Feb. Z6, i924.

STANISLAVV VADAS, OF PEILADELPHA,

PENNSYLVANIA. i

MncnaNrcaL-,sronne lrunNiicn onere. I

Application ledSeptember 15, 19721: Serial No. 500,751..

To all whom t may concern.'

Be it known that I, STANrsLAw VVADAS, a citizen of the United States ofAmerica, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain `new and useful Improif'ements in Mechanical-Stoker Furnace Grates, of which thefollowing is a specifi cation. Y

rlhis invention relates to certain new and cker furnace grates and its object is to provide a simple and durable apparatus which will secure a more perfect and uniform coinbustion of fuel than has heretofore been attained, and consequently a more economical andefiicient operation for obtaining greater and more uniform 'steam pressure.

With the above. general object in view and others that will appear as the nature of the invention is better, understood, the, saine consists in the novel form combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawings andl claimed. i

In theY drawings forming a part of this specification and in which like characters of reference indicate corresponding., parts throughout vtherseveral views, ,e

vFigure 1 is a side elevational view of a mechanical stoker grate constructed in accordance with the present invention shown operatively associated with certain accessories which are illustrated in vertical section, 1 y' Figure 2 is a front elevational view of the stoker grate shownrin Figure 1,

Figure 3 isa top plan view of the'device shown in Figure 2,r K i Figurei is a fragmentary view showing the'lo'wer portion of the device shown in Figure2 in substantially central'longitudinal section, A Y Y Figure 5 is a view similar to Figure ,4e of the upper, portion of the device shown in Figure 2, y' Y Figure 6 is a sideelevational view of one of the grate bars of one set forming part of the main grate, and

Figure 7 is a view similar to Figure 6 of onel ofthe gratebars of theother'set of the main grate. A Y e The furnace is constructed with a fire bridge 5 and anl arch 6,. alcove which is placedY the boiler 7. Between the frontrof the furnace and thefflre bridgeV are placed three grates, the forward andupper oneof' which 8 is vthe coking grate, the intermediate or second one of which 9 isthe main inclined grate, and the third or lower and inner one of which 10 is the dumping grate. The main gratey 9 is composed of two'series of grate bars one of which is vibratory about a tranverse pivot near the lower end of said'main grate while the other of whichis vibratoryV about a transverse,l horizontal pivotnear the upper end of saidinain grate, a grate bari'A of `the first series beingshownin Figure 6 and that of the secondseriesA being shown in Figurer 7 A`and respectively designated by thenuinerals v11 and 12. l

The present stoker includes, a pair" of side frames' lfrwhieh are connected intermediate ltheir ends by a transverse horizontalbar la'upon which the grate bars fllrandf12 restY at their central portions, said' grate bars being cut out to form hook- shaped members 15 and 16 vdisposed to loosely'partially Vembrace the bar le so a's-to permit transverse vibration of'said bars while retainingxthe same against downward'longitudinal movement as they wouldotherwisetend to move by gravityv by reason of the facttl'ifat they are narranged at anY inclination.'V Further transverse lbars 17 and 181connectthe frames so i' 1 3 ata point-beneaththe upperandlower ends of the grate' bars 11A and 12 andQfurnish Vfurther rests for supports for-saidgrat'ebars at times duringtheir'l operation'.` "Thefgrate bars 11 are provided with eyes 19 near their lower ends through whicha transverse pivot rod y2O extends, whilethejgrat'e bars 12,r are provided` with transverse openings 21 near y their upper ends through'which a substan` tiallyA horizontal'j transverse pivot rod.` 2,2 eir-Y tends, the grate bars llvbeing'out yout as at I23 so that the pivot rodf22 does not extend therethrough.` butY is dispposed heneathl the 'same in'said out out. A pair'offirock shafts 24 and 25 are journaled in the top inclined members of thev frames 13' respectively near the upper and loweren'ds'offthe latter, and these rock; shafts are, provided with 'rela'- tively long crank portions 26 and 27. ,The

crank portions 26 engage in vforwardly directed hook members 28 formed on the upper ends of the gratebars 117 and the crank portion 27 engages somewhat similarv hook'membersY 29 provided-"onthe lower `ortion ofthe grate bars 12, saidcrankportion26 passing Y Vunder ,the upper ends of the bars 12 and the crank'portion 27 passing under the lower ends of the barsl 11.

An arm 30 is rigid with and depends from member of the rock shaft 24 and is connected by a link bar 31 to the free end of an angular' member 32 which has its other end pivoted asi/at 33fon a plate 34 which is firmly fired upon the front plate of the furnace; The angular member 32 is loosely and pivotally connected as at 35 between the pivot 33 and the connection of the link 31 with said member 32 with a sleeve 36 which is adjustably fixed upon a depending bar 37 strapped to an eccentric 38 which is fastened upon a transverse horizontal shaft 39. The shaft 39 is suitably journaled in the frames 13 beneath and forwardly of a hopper 40 provided at the upper portion of the apparatusoutwardly of the arch 6, and on said shaft 39 is also hxed another eccentric to which is strapped a further but longer depending bar 41 which in turn carries an adjustable sleeve 42 which is loosely and pivotally connected as at 43 to the central portion of an angular member 44, the member 44 having one end pivotally attached to the plate 34 as at 45 and having its other end pivoted to one end of a link bar 46. The link bar 46 has its rear endY pivoted to a depending arm 47 fixed to a member of the rock shaft 25.

A still further eccentric is provided upon the shaft 39 near one end thereof outwardly of the eccentric 38, and an upwardly eX- tending slotted bar 48 is strapped to this further eccentric, the bar 48 having a longitudinal screw 49 and a nut50' adjustable thereon within the slot of the bar longitudinally of the latter,` which nut is pivotally connected as at 51 to the'ends of upwardly extending arms 52 which are rigidrwith a horizontal rocking feed bar 53. Thejfeed bar 53 substantially forms the bottom of the hopper 40 and includes a substantially flat plate portion beneath which is disposed a rigid horizontal bar 54 over which the forward upper ends of the bars 55 of the coking grate Y8 are hooked, said coking grate bars 55 being extended rearwardly through a slot inthe plate 34 and having their lower rear ends resting upon the upper ends of the grate bars 11. In order to provide for the engagement of the grate bars only with the grate bars 11 and to provide spaces between the contacting ends of the grate bars 11 and 55 for the admission of air, the grate bars 55 are provided with longitudinal narrow ribs 56 upon their under sides which rest upon the upper ends of the grate bars 11.

A substantially horizontal ash pit 57 with downwardly converging sides is provided beneath the grates 8, 9, and 10, and above the rear portion of this ash pit are disposed a plurality of transverse rotatable grate bars 58 forming the dumping grate 10, said grate bars being preferably journaled in the frames 13 slightly below and rearwardly of the lower ends of the main grate bars and being intergeared by means of spur gears 59 or the like whereby rotation of one bar will cause the opposite rotation of the adjacent bar for damping the ashes into the ash pit as the saine is formed by consumption of the coal upon said grate bars 58. A spiral conveyor 69 is join il longitudinally and centrally of the ash pit 57 and so disposed as to convey the ashes forwardly from a point beneath the grate hars so as to keep the ash pit clean or substantially so and this conveyor is also longitudinally slidable or displaceable for a purpose which will presently become apparent. A transverse horizontal shaft 61 is onrnaled in the frames 13 beneath the shaft and has a relatively large bevel gear 62 fixed thereon in position to mesh with bevel pinion 63 fixed upon the forward end of the sl aft of the conveyor which projects through the plate 34, the gear pinion 63 being` normally held in engagement with the bevel gear 62 by means of a relatively strong helical spring 64 which surrounds the shaft of the conveyor 60 between the plate and the pinion 63, said spring 64 acting to displace the conveyor to the full line position of Figure 4 from the dotted line position thereof. The means for rotating the shaft 39 is not illust-rated but said shaft may be rotated by a gearing or by pulley or by small engine with the rotation thereof timed, and in order to transmit such rotation of the shaft 39 tothe shaft 61,V alined sprocket wheels 65 and 66 are respectively secured upon adiacent proiecting ends of the shafts 39 and 61 with an endless sprocket chain 6'? passing therearound. ln order to throw the conveyor 60 out of operation and to maintain the same out 'of operation, the shaft of said conveyor'fiO is associated with a hand lever 68 having a spring pressed catch and rack bar whereby rearwardly tilting of the lever 68 will bring the latch into engagement with a tooth of said rack bar as'shown by dotted lines yin Figure 4 for holding the conveyor 69 in e rearward position with the pinion out of engagement with the gear 62 Y Another sprocket'-wheel 69 is fastened upon the projecting end of the shaft 61 in line with a sprocket wheel 70 fastened upon the projecting end ofthe shaft of one of `the grate bars 58, and an endless sprocket chain 71 passes around the sprocket wheels 69 and 70 so as totransmit motion from the shaft Y 61 to the grate bars 58 in the presence of the gears 59. The shaft of the grate bar which carries the sprocket wheel '70 is denoted by the numeral, 72 and as shown inY A Figures 1 and 3, said shaft is providedl wit Y' clutch teeth arranged to cooperate with clutch teeth upon the adjacent side of the hub 73 of the sprocket wheel 70, which hub is slidably mounted upon the reduced free end portion of the shaft 72 so as to provide Y engagement thereofy while at the same time permitting manual disengagement of said clutch teeth.

In operation, coalb is delivered in anyl desired manne-r into the hopper 4:0 and the teeth ofthe hub 7 3 are normally` disengaged as is also the bevel pinion 63 and the shaft 39 is then. slowly rotated, the feeding device 53 being rocked so as to project andv retract and gradually feed the coal onto the coking grate 8 which is slowly agitated by this conu nection with the feedingdevice and its association with the upper ends of the grate bars 11. At the same time, the shafts 24 and25 are slowly rockedsoas tovcausevertical swinging to the grate loars11 and 12 about their respective pivot rods 20- andZQ so that each grate bar 1'1 vibrates one of the grate bars 55. The fuel is thus gradually removed from the hopper 40 down over the surface of the coking grate and the main grate until it reaches and covers the dumping grate, reaching to the front of the fire bridge 5. As the fuel passes upon the coking grate and becomes ignited, it receives a sufficient quantity of air through the spaces between the adjacent ends of thegrate bars 55, 11 and 12. The smoke generated in the coking process is thus quickly and practically entirely consumed, adding to the lheat of the furnace and substantially obviating its escape through the stack. Through the agitation of the coking and main grates, the fue] is gradually passed down upon the main grate. where it continues to receive a quantity of air duly proportioned to the state of its combustion. By the time the fuel reaches the lower portion of the main grate 9, it is eectively coked and live fuel is in little or no danger of falling through the spaces between the grate bars into the ash pit below.

As the ashes accumulate upon the grate bars 58 of the dumping grate 10, they may be dumped into the ash pit 57 from time to time by throwing the hub 73 into operation by means of the lever 74 so that the grate bars 58 are rotated. Also, said ashes may be conveyed out of the ash pit from time to time so as to insure proper updraft between the grate bars 58 by permitting the forward movement of the conveyoruntil the` pinion 62x engagesthe gear 62.

From the foregoing description, it is believed that the construction and operation aswell as the advantages of: the present in vention will be readily understood and.` 'ap'- preciated by those skilled in the art.

Minor changes may be made without de parting'from the spirit and scope of the invention asherein claimed'. i

That is claimed Yas new is: 1. In a mechanical Stoker furnace grate, a hopper, a rocking feeder bar journaled upon a horizontal axis, a coking gratev includingA separate gratevbars having their upperends pivoted to said' feeder bar and co'- operating therewith to form a bottom, for said'v hopper, a main grate including grate bars alternate ones of" which arermounted near their lower ends for swinging move? ment or vibration and the remaining ones of which are mounted near their upper ends for swinging vibration, said grate bars of the coking grate having their lower ends restingiipon the upper ends ofvsaid alternate grate bars of the main grate, Vthe bars of the coking and main grate extending longitudinally of!v the furnace with the bars of the main 'grate inclined, and means to vibrate i all of thevgrate bars of said main grate.

2. In a mechanical stoker furnace grate,

a hopper, a rocking feeder bar Vjournaled upon a horizontal* axis, a coking grate including separate grate bars having their upper ends mounted onfsaid feederbar, and

cooperating therewith to form a bottom for said hopper, a main grate including grate bars alternate ones of which are mounted near their lower ends for swinging movement or vibration and the remaining ones of which are mounted near their upper ends for swinging vibration, said grate bars of 1 the coking grate having their lower ends resting upon the upper ends of said alter nate grate bars of the main grate,.thevbars of the coking and main grate extending longitudinally of the furnace with the bars of the main grate inclined,meansto vibrate all of the grate bars of said main grate, and a transverse driving' shaft, the means for vibrating the grate bars of the main grate and the meansfor rocking said feeder barbeing operatively connected to said shaft.

3. In a mechanical Stoker furnace grate, a hopper, a rocking feeder bar journaled upon a horizontal axis, a coking grate including separate grate bars having their upper ends mounted on said feeder bar and cooperating therewith to form a bottom for said hopper, a main grate including grate bars alternate ones of which are mounted near their lower ends for swinging movement or vibration and the remaining ones of which are mounted near their upper ends for vibration, said grate bars of the @cking girate having their lower ends resting upon the upper ends of said alternate grate bars of the main grate, means to vibrate all of the grate bars of said main grate, the bars of the coking and main grate extending longitudinally of the furnace with the bars of the main grate inclined, the means rocking the bars of the main grate including transverse rock shafts having upwardly directed crank portions, and said grate bars including hook members engaging said crank portions.

4. In a mechanical Stoker furnace grate, a hopper, a rocking feeder bar ournaled upon a horizontal aXis, a coking grate including separate grate bars having their upper ends mounted on said feeder bar, and cooperating therewith to forni a bottom for said hopper, a main grate including grate bars alternate ones of which are mounted near their lower ends for swinging movement or vibration and the remaining ones of whichV are mounted near their upper ends for vibration, said grate bars of the coking grate having their lower ends resting upon the upper ends of said alternate grate bars of the main grate, means to vibrate all of the grate bars of said main grate, the means rocking the bars of the main grate including transverse rock shafts having upwardly directed crank portions, and said grate bars including hook members engaging said crank portions, a pair of frames in which said rock shafts are journaled, a transverse bar connecting said frames at a point substantially midway betweenthe ends of the grate bars of the main grate, and hook members upon the grate bars of the main grate engaging said transverse bar to hold said grate bars of the main grate against downward displacement,

lthe last named grate bars being rearwardly inclined, and the bars of the coking and main grate extending longitudinally of the furnace.

5. In a mechanical Stoker furnace grate, a hopper, a rocking feed bar having a transverse rigid bar member, a coking grate including a plurality of grate bars with hooks upon the forward ends of the same engaging over said rigid bar member and cooperating with said rocking feed bar to form a bottom for said hopper, a main grate including bars upon the upper ends of which the lower ends of the coking grate bars rest, said ooking grate bars being provided with longitudinal narrow ribs spacing the lower ends of said coking grate bars from the upper ends of the main grate bars for the admission of air, said main grate including grate bars alternate ones of which are mounted near their lower ends for swinging vibration, said gratebars of the coking grate being of such width and with their longitudinal ribs so disposed as to only engage said alternate ones of the main grate bars, the bars of the coking and main grate extending longitudinally of the furnace with the bars ofthe main grate inclined.

In testimony whereof I aiX my signature.

STANISLAW WADAS.

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