,UNrrsD STA-Tes PATENT @errent yECKLEY B. GOXE, OF DRIFTON, PENNSYLVANIA.
'SPECIFICATION forming part of Letters atent N o. 518,578, dated April 1'?, 1894. .Application iiledNovemher 27, 1893. Serial No. 492,083.. (No modell) To all whomz't may concern: a', b', c', d', respectively, from the air-supply VRe it known that-I, ECKLEY B. COXE, aciticonduit or air-pipe, 2; which conduit, when een of the United States, residing at Dritten, used,is in'communication with some suitable 55 fln the ,county of Luzerne and' State of Penn-l pressure-blast mechanism or apparatus, as, 5 sylvania, have invented certain' new and use' for instance, the fan-blower, N; this blowerful Improvements in Furnaces, of'which 4the may be `actuated by connection with some lfollovving is a specification. y Y suitable source of power, as, for instance, This invention relates to furnaces, and is by the connectingdriving-belt,`3, running 6o n the nature of an improvement on the in- -over the driving-pulley, 4,` en a revolving lo Vention described and claimed in Letters line-shaft-, 6. Said air-supply mechanism, Patent of the United States No. 499,716," or blower, being in operation at the proper granted to'rneJune 20,18935and mypresent speed for supplying the highestpressure improvements are herein shown in connecair-blast required, the other air-blasts are tion with the multi-blast traveling-grate furreduced to the required pressures, respectl g 5 nace described in'said patent. i ively, by means of the several'air-valves de- The object of my present invention is .te scribed. .In practice, o'nly amoderate airprov'ide on organization of mechanism or ap-` Y pressure is used in the first air-blast appa.- paratus whereby, in a furnace-plant of the ratus'ct, the pressure here being made suit- A7e class described, the plenum of air in the furable for ignition of the fuel'when this rst zo nace-chamber normally due to the high-press enters the furnace-chamberat the forward urel air-blast may be controlled to prevent the end thereof, which is at the right-hand in the re-action thereof upon the successive low-v drawing. The second. air-blast apparatusb.
pressure air-blast or blasts, for the purpose is .usually the one which is supplied with air ofmak-ing moreuniform the operation of the at the maximum pressure, in practice and z5 steam-plautand permitting the-useof alower especially` when burning small-size anthrapressure air-blast. with more `uniform results cite, this pressure is usually equal to one-inch during* the later stages of the combustion orone and'one-half inches of water. AIn the period; VAalso to provide Vmeansfor obtaining next air-chamber c, the 4pressure is reduced 8o the required variable air-supplies without the to about two-thirds,or even to one-half, of the 3c use of a pressure-blast apparatus.A pressure inthe chamber b; `while in the last In the drawing'is shown, in sectional side chamber of the series-itis reduced to a much elevation, 4a furnace-plant embodying my lower point, frequently notl exceeding the presentimprovemnts. f pressure of one-fourth o f aninch of water. 85 The furnace shownin-thedrawingis ormay `It will be,` understood that, 'in any case, by 35 be the same as the furnace described in my pressure as applieito an air-supply, is l afOI'eSaid prior Letters Patong/and which .meant thepressure o f the same incompari-- consists of the usual walls inclosing the furson with pressure Withinthe furnace-chamnace-chamber C; a fuel-conveying' grate, G, ber; and that whether this pressure be above `9e provided with' means" (substantially asgdelor below that of the atmosphere is not mao scribed in said patent) `for actuating the terial. L grate; y means, as, for instance, the hopper H, The tendency of thehigh-pressure air in the for supplying fuel to the upperrnn of said air-blastfromthe-chambel-b naturallytendsto conveyor-grate; a series of variable-pressure createasurplus or over-,pressurein thenearlyslr-supply apparatuses, designated by a, Inc, closed' furnace-chamber, thus causing a red, respectively, and located underneath the lacting back-pressure of sutiicient magnitude fuel-conveying furnace-Hoor, as indicated in to overcome the inlinx ot' the lower pressure `the drawing; and, means for supplying said airblasts,and thereby detroy their efficiency;
` air-supply apparatuses or chambers a, b, ad, that action also makes lthe lowest-pressure zoo respectively, with air at the required pressair-blasts variable in effect. To overcome i 5o ures. The measforcontrolling the successthis objection I have provided, in connection ive airsupplies consists or may consist of the with the discharge-end of the furnace-charnregulating valves a, b, c7211, in the pipes ber,an exhaust apparatus adapted for reduc ing the air within the furnace-chamberto a Vafter these have been used. The exhaust apparatus, in the form thereof herein shown consists of a, blast-nozzle, 7, V(which will usually be a ksteam blast nozzle) located in the stack or liuc at some suitable point in or beyond the outlet` of the furnace-chamber. This b1ast-nozzle 7 is suppliedV with steam from asuitable steam supply, as, for instance, the steam-boiler which is shown in connection with the furnace. In the drawing, the steam nozzle 7 is shown centrally disposed within yand somewhat below the contracting-A rng 8 of the stack. The nozzle is supplied through the pipe 9 in which isa valve, 10, for regulating the supply of steam tosaid nozzle. In practice, this valve will require regulation in connectionwith the regulating air-valves a, b, c,d", so as to properly adjust the exhaust-blast toene or more of the 'several air-blasts.
In operation, the ejectionof steam from the blast-nozzle 7 creates a suction in the furnace-chamber sufficient to' carry off the surplus airand secure the requisite result in the reduction ofair-pressure therein', thus ohviating reacting back-pressure.
By the construction and organization of apparatus as herein described, the fuel, in a layer upon the furnace-floor, is subjected from below to the action of successive airblasts ofvarying pressures, and the resultant air-pressure created in the furnace-chamber by the higher pressure blast ofA the successive air-blasts is reduced by suction so as to have no counter-acting eect upon the lower-pressure air-blast which would otherwisedestroy the efficiency.
Having thus described my invention, I
claim-7n In a furnace of the class specified, the combination with the furnacechamber and its nclosing walls, and with the furnace-floor located under said chamber,of high-pressure and low-pressure airblast apparatus located below and in communication `with the furnace-floor, and a blast-apparatus located near the discharge-end of the furnace-chamber and adapted for reducing the absolute airpressure in said chamber to a pressure below xthat of the lowest-pressure air-blast apparatus, to prevent re-acting backfpressure, substantially as described and for the purpose set forth.
'IECKLEY B. ooXEk.
Louis OBTNER, STEWART F. MACFARLANE.