USRE12254E - Reissued aug - Google Patents

Description

L. T. WRIGHT.

ROASTING FURNACE.

APPLIOATION FILED MAR. 9, 1903.

3 SHEETS-SHEET 1.

REISSUED AUG. 2, 1904.

INVENTORY SHEET 3.

3 SHEETS AIPLIOATION FILED MA]!- 9, 1903.

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' UNITED STATES Beissued August a, 1904.

LEWIS T. WRIGHT, OF KESWVICK, CALIFORNIA.

ROASTING-FURNACE.

SPEGIFIGATION forming part of Reissued Letters Patent No. 12,254, dated. August 2, 1904.

Original No! 629,023, dated July 18, 1899. Reissue No. 11,982, dated September 17, 1901. Application for present reissue filed March 9,1903. Serial No. 148,8005.

. to w at is knownas the McDouga'lWrooistseries of floors of brick having discharge-opening-iurnace, and I shall describe it asappliedthereto, it beingunderstood thatI do not limit the application of my invention to any one form of furnace.

The McDougall furnace contains a vertical ings in each floor to the floor next below alternately at the circumference and at the center. A. central shaft is provided having arms extending over these floors, said arms carrying rabbles, and the rabbles on the series of. arms are alternately inclined,.. soas to'gradually work the ore that is being roasted first outward to the circumference, where it is discharged through an opening onto the floor below, then from the circumference to. the center, where it is discharged through a central openlng onto the next floor, and so on, being finally discharged from the lowest floor at the circumference. At the same time the air necessary for combustion of the ore passes upward in the reverse direction to the downward movement of the ore. 3 Now the heat required in roasting certain ores is such that the central shaft, the arms, and the rabbles thereon have buta short lifetime and are always in danger of being disabled. by momentary excess of heat; and the object of my invention has been to provide means for cooling these parts, so as to give them greater durability and to enable the temperature of the furnace to be increased, if desired, considerably above such a temperature as would, if employed with uncooled arms, rapidly result in their destruction.

My invention also resides in the novel conwithout the rabbles.

struction, combination, and arrangementlof parts hereinafter fully specified, and particularly pointed out in the claims.

In the accompanying drawings, Figure l is. a central vertical section of the apparatus. Fig-2 isa'vertical section, on a larger scale, of the upper portion of the hollow driving shaft or column and the water-pipe connections. Fig. 3 is a similar view of the lower portion thereof. ,Fig. i is a plan-view of a detail. Fig. 5 is a vertical section of the lower end of the hollow shaft and an arm extend-- ing therefrom broken, partly in section and partly in side elevation. Fig. 6 is a plan view from below onepf the arms withthe rabhie-holding sections in position therein, but Fig. 7 is asimilar view, enlarged, but showing one rabble in position in the holder; and Fig. 81s an enlarged transverse section of an arm with a rabble-holder and rabble therein.

" Referring to the drawings, 1 represents the circular wall of a McDougall roasting-furnace having the brick arches or floors 2, the

ore-feeders 3, and stack i of theusual construction. Upon a pier. 5 of masonry is stepped, as shown at 6, a central vertical shaft 7, carrying a bevel-gear 8, driven through a pinion 9 from any suitable source of power. Said shaft Textends through central apertures in the floors 2 of the furnace, of which apertures alternate ones, aslO, are closed around the shaft, whereas the other apertures, 12, are of greater diameter and formpassages through the floors for the descending ore and ascending currents of air. Passages through the other floors are formed at the circumference, as shown at 13. The shaft 7 is revolubly supported at its up er end in a. bearing 14, suitably mounted on beams 15 at the top of the furnace. From said shaft 7 extend arms 16,- there being two such arms immediately over each floor in opposite directions from. the shaft, arms over alternate floors being arranged at right angles with each other.

To the under side of each arm are secured a number of rabbles 17, set obliquely to the arm, the function of such rabbles being to stir the ore and gradually work 'ing in said arms on the outside of the branch and inward along successive floors and underascending in the reverse direction, being finally discharged through the pockets .19.

All of the above construction is well known and forms no part of my invention, which I will now proceed to describe.

in my invention the shaft 7 is made hollow and is connected above the bearing 14 by means of a stuffing-box 20 to a head-piece 21, suitably packed in said stuffing-box, as ShOnD. at 71, which head-piece does not rotate, but is held by stays 22, mounted on the I-beams 15. From the top of the head-piece 21 ex-v tends centrally downward a feed-water pipe 23, into which wateris supplied from any suitable source, saidpipe being of such length as to approach within a short distance of the bottom of the hollow shaft 7. The water discharging from the open bottom of the pipe 23 escapes into the bottom of a pipe 24 of goes continued exposure to currents of airl I larger diameter than and surrounding said pipe 23 and closed at the bottom, so that the water now flows upwardly in said pipe 24. Into said pipe 24 are screwed, as shown at 25, small branch pipes 26, extending horizontally from the pipe 24 into the/arms 16, which in my invention are made of piping closed at the end by removable caps 28 to permit of inspection of the interior v of the arms 16 and of the branch pipes 26 therein, the outer ends of said branch pipesbeingjsupported in said arms 16 by spiders 66. The water flowing upwardly in the pipes 24 passes radially out-. ward in the pipes 26, escapes from the open ends of said pipes into the arms 16, returnpipes into the hollow shaft? outside the pipe 24 and continues to ascend in the shaft 7. A spider 29 is mounted between the pipe 23 and the stuffing-box 20, and said spider serves to hold the top of the pipe 24 and close the annular space formed by the pipe 24 around the pipe 23. Through this spider the water passes from the hollow shaft 7 aroundfhe pipe 24-into the interior ofthe stuffing-box 20, thence through the head-piece 21, and out by an exhaust-pipe 30. By'this means the arms of the stirrer are sufficiently cooled to withstand the action of the intense heat of the furnace.

.low column or shaft '7.

The rabbles for stirring the ore are in my invention attached to the arms 16 in the following manner: Upon each arm 16 a number of clamps are secured by means of setscrews 36, so as to extend downward from the arms, the lower portion'of said clamps being bent around to formclaws 37, adaptedto engage the sides of a rabble-holder 38. Said holder corms-la a bar to slide w 1m ihe claws if of clamps 35, having ril t? long metal plates. if desired, be for; r.

5 other between the claws of the sen V rlan ips on any arm. it will readily be seen that with this eonstruction the rabbles and their lmldercan be readily removed from the arms l6 and. replaced thereon for the purpose of inspection,repairs. or renewal. in the same manner the attachment of the hollow arms 16 to the central shaft 7 is such as to facilitate removal and replacement, said arms being threadednear their inner end, as shown at 60, and screwed into flanged collars 61, secured on flanged sleeves 62, said sleeves being mounted, as shown, on apertured bosses 63, cast on the side of the central'hol- The cxtren'ie inner end of the arm 16 is'turned to fit snugly within said sleeve 62 to better support the arm.

Doors 70 are provided in the wall of the furnace, through which the arms and the branch pipes therein and the rabble-holders support; ed thereupon can be withdrawn.

. In my invention also the central openings for the shaft of those floors which discharge peripherally are made sufficiently large to permit said shaft to be hoisted out with out the necessity of pulling out any of the brickwork and are closed by removable plates 11.

I claim- 1. In a roasting furnace, the combination, with aseries offioors, of a central hollow shaft, hollow arms carried thereon over the respective floors, an open-bottomed pipe inserted in said shaft, an intermediate pipe in said shaft into which the first pipe discharges, openended pipes leading from the intermediate pipe into the hollow arms, and. feed and exhaust pipes connected to the first pipe and hollow shaft, substantially as described.

2. In a roasting-furnace, the combination, with aseries of floors, of a central hollow shaft, hollow arms carried thereon over the respective floors, an open-bottomed pipe inserted in said shaft, an intermediate pipe in said shaft into which the first pipe discharges, a spider between the first pipe and the shaft. supporting, and closing the top of, the intermediate pipe, open-ended pipes leading from the intermediate pipe into the hollow arms, and feed and exhaust pipes connected to the first pipe and the hollow shaft, substantially as described.

3. In a roasting-furnace, the combination, with aseries of floors, of a central hollow shaft, hollow arms carried thereon over the respective floors, an open-bottomed pipe inserted IIS shaft into which the first pipe discharges at hollow arms carried thereon over the respec- -tive floors, an open-bottomed pipe inserted the'intermedia'te pipe, open ended pipesle'ading'fromithe intermediate-pipe intoj thefhole ed to the first pipe, and the 6. In a roasting-furnace, the combination, I withaseriesof floors, ofacentral-fhollow shaft,

tire-floors, an open-bottomed pipe inserted -in 'said shafhan intermediate pipe? iii said shaft intowhich the first. pipe discharges at v the bottom, open-ended pipes 1 leading from theintermediate pipe into the: hollow arms", spiders withinv the armsa'r'ound the open ends 'of'saidpi'pes," and feed and'exhaustpipes con- "nected to the first pipe and hollow shaft; Sub-1.

45' with a series offlo'o'rs, of a central'hellowshaft,"

v hollow arms carried thereon over therespec-u; 1ti-ye floors',- an open-bottomed 'pipe inserted i.

'in said shaft, an'intermediate closed-bottomed -chargesat thebottom, open-ended;pipeslead-, ing from the intermediate pipe into thehollow'ar'ms, and'lfeed -and exhaust;=pipes .con;

-; nected' tozthe first pipe and hollow shaft, sub

' Wiith'a series offloors, of acenti'al hollow shaftj Q 3 "hollow arms' vcarriedithereonover th'e respee v pipein said shattihto whiehthe'firstpipe nhar e at the: bQttbmJ-aspiden between the 1 '-first' pipe and, the shaft, supportinggandi'elos' in said shaft,an intermediate pipe in said shaft into which the first pipe discharges, open-ended pipes leading from the intermediate pipe into the hollow'arms,spiders within the arms around theopen ends of. said pipes, and feed and exhaust pipes connected to the first pipe and hollow shaft, substantially as described. j

4. In a roasting-furnace, the combination, with a series ofx'floors, of a centralhollow shaft, hollow arms carried thereon over the respective floors, an open-bottomedpipe inserted in said shaft, an intermediate pipe in said the bottom, open-ended pipes. leading from the intermediate pipe into the hollow arms, and feed and vexhaust pipes connected-to the firstpipe and hollowshaft, substantiallyas. described V r f I v f 5. In a roasting-furnace, the combination; with a series of floors, of a central hollow shaft,-

in' said shaft, "an intermediate pipe in said shaft into which the first pipe discharges at the bottom, a spider between the first pipe and the shaft, supporfiing, and closing 'the top of,

low' arms,- and feed and-{exhaustpipes connect I v hollow-shafai'sub stantiallyas described;

hollow arms carried 1 thereon over the respec-'- stantially as d ascribed,

. 7,: In-aroasting-furnace, the esmbihatiom pipe in said'shaft into whi ih the first? pipe disstantially as"described:-

I. a 8-5 In a roasting fnrnace, the combination,

fiveew fe frleer b fieme r w s e in said shaft, angiiitermediate closedbottomed J IH WItDGSS WhBI'GOf-I have hereunto set "hand this'4th dayliofz Eebruary; 1-903.- LEWISTJWRIGHI, v Witnesses':.,.g Jing the" top fof,'. the' interniediate pipav opem ended pip s]- leading from; the intermediate hollow shaft,.substantially' as described.

pipeinto the hollow arms,"a nd feed'and exhau'st pipes connected to the first pipe and the hollow arms carried thereon over the respec tive-floors', an open-bottomed pipe inserted in said shaft, an intermediate closed bottomed pipe in said shaft into which the first pipe discharges at thefbottom, openended pipes leading from the intermediate pipe mm the hollow arms, spiders within the arms around 'theopen ends-of said pipes, and feed and exhaust pipes connected to the first pipe and hollow shaft-substantially as described. 10. Inaroasting-furnace, thecombination,

with a series offloors, 'ofa central hollowshaft, sleeves secured to-th'e shaft," hollow arms haviing their ends'ins'erted insaid sleeves, and threaded outside said sleeves; threaded-"collars on said threaded portionsan'd' secured "to said sleeves, vand a feed -j ipe. for supplying water to said hollow shaft and arms, Substanf V tiallyas described]; I

11. Ina roasting-furnace, the combination of arabble-arm, clamps remotiab'lyjseeured at intervals therealong, saidclamps-"carrying' guides in line withreach other'parallel to-saidarm} a rabbleholder slidablyheldEinsaid gnid'eafand rabbles secured to1saidholder,"

substantially as'des'cribed;

. 2; In aroasting-furnace, the combination fof' a rahbl'e sarm, clamps. removably secured .thereonl'jrabhle-holder sections heldin said f'clamps and-longitudinally removable there from: S id .Sctions.having.downward-1 7px; tending ribs, and; rabbles ,removably secured- 'toisaid ribs, substantially as described.*'; r

" alroewble h low shaft passin 13-.w Iri 1 a furnace having a plurality (of the jsereralh'earths, an inner -water-feed .pip'e I located within and" rotatablegwith the shaft," and a s'eries ofjhranches or distributingmipes .IeadiIIgQfifQmsjaid feed pipe and communicat-l. in}; with the interior of the hollow arms,-suh

stantial'ly described; 1

14.111 agf fernace 'haVing-Q-a plurality of hearth's-,-' Y a rotatable hollowshaft passing throughrthe-hearthe agseries ofhollowfarnis' radiating-fromsaid: shaftiand'extendingdnto I a the SerreraL-hearths; anjinner1waterf eed pipe: I 1 -r fclosed at the bottom, located, within the shaft; I

a "and 3rotatableftherwi h;- and a s'ries of ljb'ranchesor distribntingpipes leading from-f said" feed-pipe and communicating," at -their 'o'uter ends with. the "interior; of the hollow arms, substantially asjdescrihed'.

"FRANG Mlwlimen'r,

IEUQENE A. BYRNEs;

roo- 7

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