US581061A - Furnace-grate - Google Patents

Description

' (No Model.) 2 Sheets-Sheet 1.

W. W. CHURCHILL.

FURNACE GRATB.

Pat ented Apr. 20, 1897.

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W. W. CHURCHILL.

FURNACE GRATE.-

w m w L p UNITED STATES PATENT 1? tries.

WVILLIAM W. CHURCHILL, OF NEW YORK, N. Y., ASSIGNOR TO THE VVEST- INGHOUSE, CHURCH, KERR & COMPANY, OF ORANGE, NEW JERSEY.

FU RNACE-G RATE.

SPECIFICATION formingpart of Letters Patent No. 581,061, dated April 20, 1897.

Application filed June 29, 1896.

To a/ZZ whom it may concern.-

Be it known that I, WILLIAM W. CHURCH- ILL, of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Furnace-Grates and I do hereby declare thatthe following is afull, clear, and exact description thereof, reference being had to tlrf'accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to improvements in grates for furnaces of that class wherein a plurality of bars are arranged transversely of the furnace in an inclined or stepped position, the front edge of one overlapping the rear edge of the subjacent bar, as illustrated generally I in Letters Patent Nos. 409,304, 409,305, and 409,650, granted to William R. Roney on the 20th day of August, 1889.

Among the objects of the invention are to simplify, improve, and cheapen the construction of the grate-bars, to produce a grate-bar better adapted to stand the heat of the furnace and which is therefore more durable,

and to so construct and arrange the bars that their interaction will tend to break up and prevent the accumulation of clinkers, and will thereby promote the free burning of the fuel. Various other advantages are obtained by the construction set forth, as will hereinafter more fully appear.

The invention consists in the matters hereinafter described, and more particularly pointed out in the appended claims, and it will be readily understood by reference to the accompanying drawings, in which Figure 1 is a longitudinal vertical section through the front part of the furnace and of the grate therein, showing the arrangement of the fuel-feeding devices. Fig. 2 is a detail in elevation, as seen from the front of the furnace, of one of the grate-bars used at the upper part ofthe grate, the two parts of which the same is composed being slightly separated to disclose the construction more clearly. Fig. 3 is a top plan view of the top plate of the bar shown in Fig. 2. Fig. 4 is a transverse vertical section of the bar shown in Figs. 2 and 3. Fig. 5 is a detail fragmentary view of the grate-bar shown in Fig. 4, show- Serial No. 597,287. (No model.)

ing the rear or fire-box edge thereof. Fig. 6 is a view similar to Fig. t of one of the bars used at the upper part of the grate. Fig. 7 is a view similar to Fig. 5 of the grate-bar shown in Fig. 6. Fig. 8 is a detail plan view of the top plate shown in Figs. 6 and 7. Fig. 9 is a view similar to Fig. 4, but showing the parts of the bar detached to indicate more clearly the construction of the interfitting rib and groove of said parts.

First referring briefly to the general illustration given in Fig. 1, A indicates one of the side walls of the furnace, B the front wall thereof, and C a portion of the bridge-wall.

D indicates the lower part of the side bearer, which rests on the furnace-floor opposite the foot or dumping grate. Said dumping-grate is omitted, as not concerned in the present invention, but occupies, when in place, a horizontal position extending transversely across the furnace at the bottom of the main grate, as shown in said prior patents.

E indicates as a whole an inclined grate composed of rocking bars embodying one feature of the present'invention.

.F is an external coal hopper or magazine, and G a dead-plate forming an inward extension of the inclined bottom F of the coalhopper.

The grate E, as shown clearly in Fig. 1, is composed of a series of transversely-arranged horizontal grate bars E E, arranged in stepped order with the rear edge of each bar overhanging the front edge portion of the next bar below it. Each bar Eis provided at its ends with trunnions e e, which rest in notches d, formed in the inclined supportingplates D, secured at the opposite sides of the fire-box adjacent to the side walls of the furnace. Preferably, and as shown in the present instance, the supporting-plates D are formed in one piece with the side bearers D for the foot-grate.

Each of the several grate-bars consists of two main portions, comprising a relatively thin vertical web-shaped body portion E made'of skeleton form, as shown, so as to re duce the weight of the bar, facilitate the passage of air therethrough to the fire, and provide suitable access for a slicing-bar for stoking the fire, and atop plate E suitably secured upon the upper edge of said body portion and having an upper surface consisting in the instance shown of a substantially horizontal front portion 6 and a rearwardly-inclined rear portion 6 The trunnions c c of the grate-bars are of novel form, being made oval or elliptical in cross-section,with the longer axis of the ellipse disposed vertically, and are also made tapering outwardly, as indicated clearly in Figs. 2 and 4:, while the notches or recesses d in the side plates D, which receive said trunnions, are correspondinglytapered, but made circular and formed on a radius somewhat larger than half the minor axis of the ellipse of said trunnions, so as to afford spaces at either side of the trunnions to permit the latter to have a rocking movement therein. The result of this construction is that the oscillatory movement of the trunnions tends to keep the bearings practically free from coal, ashes, and dust, inasmuch as any particles which are small enough to drop into said trunnionnotches are rapidly crushed or ground int-o fine powder by the rocking movement of the trunnions in their bearings, and theinwardlyinclined bottoms of said recesses insures that the dust or powder thus formed will work downwardly and out of the hearing.

The lower member ll of the grate-bar is provided at its upper edge with a plurality of bearing-surfaces c c c, arranged in this instance one at each end and one atthe center thereof. Vithin said surfaces are form ed longitudinally-arranged notches c, adapted to receive a corresponding rib 6, formed centrally upon the under side of the upper memher or top plate E The bearing-surfaces c c e" are elevated above the edge of the bar, so as to form open spaces or slots between the bar and the top plate; The bearing-surfaces c c are formed in part by lugs 6 which extend horizontally forward or toward the front of the furnace, beneath the front part of the top plate, through which latter are inserted bolts a which also extend through suitable vertical apertures in said lugs, the top plate being countersunk around the bolt-apertures to receive the heads of the bolts a which are flush with the surface of said plate. Said top plate is provided on its under side with a series of closely-spaced transversely-arranged depending flanges or ribs 8' c, which extend in a direction from front to rear of the plate. Said ribs are so located and the bars are so arranged with relation to each other as to cause the rear or inner parts of the ribs of one bar to overhang and extend adjacent to the top surface of the front portion of the subjacent bar so that when said bars are oscillated in one direction said ribs will be brought down in to contact, or nearly so, with the surface of the subjacent bar, thereby serving to crush and break up any clinker or coal which may be resting upon that part of the bar. This action obviously keeps each bar free from adherent clinker and allows the fuel to pass freely downward over the grate during the reciprocatory motion of the bars. Those ribs 0 which are transversely opposite the lugs e c 0 will obviously only extend from the rear side of the grate-bar forwardly to the rear edges of the lugs, as indicated in Figs. 8 and 4:.

The ribs 6 are shown as made with obtuseangular edges at the lower margin of their forward end portions, as shown at 6 the said angular sides serving to improve the crushing or breaking action of the ribs. The front parts of the ribs c" serve more especially to increase the amount of cooling-surface of the grate-bar and stiffen the same in a way to prevent warping or twisting thereof.

In order to prevent the fine coal and slack from falling through between the grate-bars, the front edges of each of the first or upper six grate-bars are provided with an upturned flange c ,such ashas been commonly and heretofore used. This flange is omitted from the lower gratebars, inasmuch as it is found in practice that the fine coal which remains uncensumed is sufficiently coked before it reaches this part of the grate to prevent its falling through between the bars.

Upon the lower edge of the vertical web or main body portion of each grate-bar is formed a depending lug or arm c of cylindric form at its end and adapted to rest within a correspondingly-shaped recess 7!, formed in the upper edge of the reciprocating grate-actuating bar H. In order to support said bar II in position beneath the grate-bars with its several notches 7t engaged with the arms e of said bars, the bar H is provided at points intermediate of its length with laterally-offset portions h h, arranged opposite the depending lugs or arms 6 of two of the gratebars and provided with apertures 7L2 hiform ed in axial alinement with the centers of the cylindrie ends of said arms, and through which extend stubs c formed or mounted upon said arms. Suitable keys or pins 0 are inserted through the ends of said studs to retain the bar II in position thereon.

An actuating mechanism for giving motion to the bar H is shown in Fig. 1, the same consisting of a rotating shaft J, mounted in brackets J and provided with a crank J which is connected by a bar K and with a lever or arm L, mounted at its upper end on a rock-shaft M, the lower end of said arm L being connected with the bar II by means of a connecting-rod I, which is pivoted to the bar II and has sliding connection with the arm limited by means of nuts i 2', which serve as tappet-shoulders for contact with the said arms, and the adjustment of which on the red I enables greater or less motion to be given to the bar II, as desired.

The particular form of grate-bar shown, in which the top plate thereof is provided with a series of closely-spaced depending flanges or fins, is of importance, inasmuch as said ribs not only serve to prevent the grate-bar from warping under the excessive heat, but also afiord a very large cooling-surface, which is exposed to the cool air beneath the grate and prevents the top plate from becoming overheated. At the same time the construction is such as not to interfere materially with the stoki-ng' of the fire from the front of the furnace should this become necessary.

I claim as my invention- 1. A grate having a plurality of pivotallymounted overlapping grate-bars having on their under surfaces depending transverse ribs or flanges opposed to the rear parts of subjacent bars, and means for actuating said bars on their pivots.

2. A grate having a plurality of pivotallymounted overlapping grate-bars having on their under surfaces depending transverse ribs or flanges which extend from the front to rear edges of the bars and are opposed to the front parts of the subjacent bars at their rear portions, and means for oscillating said bars on their pivots.

3. A grate provided with a plurality of pivotally-mounted, overlapping skeleton gratebars, each having a fuel-supporting top plate provided on its under side with a series of transversely-arranged, closely-spaced, depending ribs or flanges, and means for oscillating said bars on their pivots.

4. A grate having a plurality of pivotallymounted overlapping. gratebars, consisting of top plates and stiffening-Webs made separate from each other, the webs being adapted to form openings or slots between their upper edges and the bottom surfaces of the top plates and said top plates being provided with trans-.

verse depending ribs or flanges, and means for oscillating said bars on their pivots.

5. A grate having a plurality of pivotallymounted, overlapping grate-bars, each comprising a main body portion having the form of a vertical Web provided at its upper edge with laterally-extended supportin g parts, and a fuel-supporting plate secured horizontally upon said main body, said fuel-supporting plate being provided on its under side with a series of transversely arranged, closelyspaced depending flanges, and means for oscillating said bars upon their pivots.

6. A grate having a plurality of pivotallymounted, overlapping grate-bars, each comprising a main body portion having the form of a vertically-arranged skeleton web provided at its upper edge with laterally-extended supporting parts, each provided with a longitudinally-arranged groove in its top surface, and a fuel-supporting plate located horizontally upon said main body portion and provided on its under surface with alongitudinally-extended rib adapted to fit within and engage the notches in said body portion, and also a series of transversely-arranged, closelyspaced integral depending flanges, and means for oscillating the bars on their pivots.

I 7. The combination, in a furnace-grate, of a series of pivotally-supported grate-bars arranged transversely of the furnace in stepped order and provided on their under surfaces with transversely-arranged closely-spaced depending flanges arranged to coact with the upper surface of the subjacent grate-bar to crush the fuel lying upon the latter when said grate-bars are oscillated,and actuating means connected with said bars for oscillating the same simultaneously, substantially as set forth.

8. In a furnace-grate, the combination of grate-bars provided with trunnions oval in cross -section and also made tapering outwardly and a side support provided with circular, correspondingly-tapered bearing-recesses adapted to receive and support said trunnions, substantially as described.

In testimony that I claim the foregoing as my invention I afliX my signature, in presence of tWo witnesses, this 26th day of May, A. D. 1896.

WILLIAM W. CHURCHILL. Witnesses:

FRANCIS E. FROTHINGHAM, ALVANO T. NIOKERSON, Jr.

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