US510575A - Traveling-grate furnace - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1, E. B. OOXE. TRAVELING GRATB FURNACE.

N0. 510,575. Patented Dec. 12, 1893.

I aI

n1: NATIONAL LITNOGHAPNING COMPANY.

WASHINGTON. n. c

UNITED STATES PATENT FFICE.

ECKLEY B. COKE, or DRIFTON, PENNSYLVANIA.

TRAVELlNG-GRATE FURNACE.

SPECIFICATION forming part of Letters Patent No. 510,575, dated December 12, 1893.

Application filed July 14:. 1893.

To all whom it may concern:

Be it known thatl, EOKLEY B. COXE, a citizen of the United States, residing at Drifton, in the county of Luzerne and State of Pennsylvania, have invented certain new and useful Improvements in Traveling-Grate Furnaces, of which the following is a specification.

This invention relates to traveling-grate furnaces of the class described in the prior Letters Patent No. 499,716, granted to me J one 20, 1893; the object being to provide means for properly regulating the supply of fuel to the middle portion and edges of the traveling furnace-floor, for preventing the premature burning-out of the fuel along the edges of the furnace-floor.

In the drawings accompanying and forming a part of this specification, Figure 1 is a plan view of a portion of a furnace embodying my present improvements. Fig. 2 is a sectional side elevation of the furnace. Fig. 3 is a sectional view, in line a" a Fig. 2, showing the parts at the right-hand of said line as seen from a point at the left-hand thereof. Fig. 4 illustrates a modification of the furnace. Fig. 5 is a plan View of the adjustable fuel-gate, and Fig. 6 is a side view of said gate.

Similar characters designate like parts in all the figures.

The furnace shown in the drawings for illustrating the nature and mode of operation of my present improvements, is similar to that shown in my aforesaid Letters Patent, with the exception of certain features shown in Figs. 1, 2, 3 and 4, and referred to in my concurrent application, Serial No. 472,891, filed May 3, 1893.

The furnace illustrated in the drawings is shown underneath a steam-boiler, B, which maybe of any well-known type; or, said boiler may be replaced by any other thing to be heated. The furnace has the usual inclosing-walls at the sides and ends thereof, and (in the absence of a steam-boiler or other device to be heated over the furnace) the ordinary top-oovering. In the drawings, the sidewalls are designated in a general way by 2 and 3, respectively, and the furnace-chamber, O, is shown covered by a steam-boiler, B. At the forward end of the furnace-chamber, this is provided with the end-wall, 4, through Serial No. 480,491. (No model.)

ing a chute comprising the inclined and lower wall 5", for delivering the fuel from the hopper tothe grate G.

The under side, or floor, of the furnacechamber 0 is formed of the fuel-carrying run,

10, of an endless traveling grate, designated in a general way by G, and preferably composed of a series of similar grate-bars, or sections, 9, pivotally connected and carried by the wheels 12 and 14, that are fixed on the two shafts 13 and 15, respectively. The ends of the several grate-bars are shown supported by guides of which those for the upper or fuel-carrying run of the grate are designated by 16 and 18, while those for the lower or re turn-run 11 are designated by 17 and 19, respectively. A suitable construction of the grate-bars is shown in detail in my aforesaid Letters Patent, to which reference may be had. In the under side of the grate-bar, or grate-section, there is formed in the end-bars thereof the notches 30 for engaging the corresponding cogs 33 of the chain- wheels 12 and 14, when the grate is driven forward.

For protection, in practice, of the ends of the grate-bars,'andalso for preventing the fine fuel passing over the ends thereof, the side-walls of the furnace are brought over the grate-bars substantially as shown in the sectional view, Fig. 3, the brick-supporting plates, 20 and 22, of the side-wall extending over the grate-bar by a distance equal to, or greater than, the width of the'end-bar 29 of the grate-section.

Under the upper or fuel-carrying run, 10, of the traveling-grate is a series of air-supply chambers, a, b, c and d, located at successive points of the length of the furnace-chamber. The air-supply chambers may be two or more in number, four of them being shown in the present instance; in general, I prefer to use not less than three such'chambers. Each of said successive chambers is to be suitably supplied with air, which may be done by blowing the air thereinto through corresponding pipes, a, b, c and (1', shown in end view in Fig.2, after the manner described in my aforesaid Letters Patent No. 499,716.

The fuel is fed to the grate ata point adjacent to the first air-supply chamber, each section of the grate receiving its fuel at or before the time it reaches the first air-supply chamber a, being then carried along over that chamber and the succeeding chambers I), c and (Z; during this period the combustible material of the fuel is consumed, and the resulting cinder or ash is afterward carried under the bridge-wall 7 and finally delivered over the rearward end of the grate into the ash-pit 21. In practice, the combustion goes on, at one stage or another, throughout nearly the entire length of the furnace, the ignition taking place within a short distance of the point Where the fuel falls upon the grate, this being completely reduced to cinder over the last chamber, d, of the series. The reduction of the fuel by combustion gradually lowers the same on the grate, (by an amount depending on the nature of the fuel,) so that at the point, 23, where the cinder passes under the bridge-wall, the thickness of the cinder is generally much less than the original height of the fuel, as illustrated in Fig. 2.

In Figs. 2 and 3, the fuel is delivered to the grate over an inclined ignition-block 6, after the manner described and claimed in my said application, Serial No. 472,891. In Fig. 4,, an arrangement is shown for delivering the fuel directly onto the grate from the hopper; but in each case the construction and mode of op eration of the grate G are, (or may be) the same.

It will he remembered that the class of furnace herein referred to is especially designed for use in burning the finer sizes of anthracite coal. This kind of fuel, when supplied to the grate in a layer and carried forward on. the grate adjacent to the fixed side-walls 2 and 3, partakes, in the portion thereof im' mediately adjacent to said walls, of the character ofa flowing stream, the particles con tiguous to the walls being held back by the friction of the mass against the surface of the wall, while the fuel on the middle portions of the grate is carried forward at the full speed of the traveling-grate. The natural result of the described action is to burn out the fuel along the edges of the grate more rapidly than over the middle portions of the same, and thus, by lightening the weight of ash and cinder on the border-portions of the grate, permit the airblast to form openings through which it may escape into the furnacechamber without passing through the heavier unconsumed fuel on the middle portions of the furnace-floor.

For overcoming the defective operation above mentioned, I provide means for distributing along the edges of the furnace-floor an extra supply of fuel, so that, notwithstanding its lesser rate of movement, it will be burned up in substantially the same time as required for the burning of the relatively thinner mass upon the middle portions of the grate. As a means for effecting this object, I provide an adjustable fuel-gate E having means for raising and lowering the same and constructed at its lower edge for delivering fuel to the extreme edge portions of the traveling-grate at a greater depth than to the middle portions thereof. The preferred construction here referred to of the fuel-gate E, is illustrated in Figs. 3 and 6; the latter figure by means of the dotted lines at the lower corners thereof, shows the spaces 25 and 26 formed by cutting away the gate, for permitting the passage thereunder of the required extra supply of fuel. Said extra supply, being delivered to the grate as specified, is carried along adjacent to the side-walls 2 and 3 of the furnace in the form of a ridge or elevation. Indicated a 27 in Figs. 2, 3 and at.

In Fig. 2, the elevation, asindicated by said line 27 of said extra edge-supply of fuel, is gradually reduced as the grate passes from the right-hand toward the left-hand of the f urnacecham her, until the depth of said edgesupply of fuel coincides with the depth of the fuel upon the middle portions of the grate; this reduction of depth resulting, as hereinbefore set forth, from the retardation of the particles by the friction of the same against the side-walls of the furnace.

The means herein shown for adjusting the fuel-gate E consist of the elevating- screws 28 and 29 which are journaled in the bearings 33 and 34, respectively, of said gate, and work in the threaded bearings fixed on the hopper II at 31 and 32, as indicated in the drawings. Said screws 28 and 29 are each shown provided with a suitable hand-wheel 30 whereby to turn the same for raising or lowering the gate as may be required. In practice, the two gate-actuating devices here described may be connected for simultaneous operation, in a well-known manner.

Having thus described my invention, I claim- 1. In a travelingrate furnace, the combination with a traveling-grate orfurnace-l'loor, and with the sidewalls of the furnace, of a fuel-supply, and a fuel-gate having an increased opening thereunder at the side of the furnace-chamber, whereby an extra supply of fuel is delivered to the edge-portions of the grate contiguous to the side-walls of the furnace, substantially as described and for the purpose set forth.

2. In a traveling-grate furnace, the combination with a traveling-grate or furnace-floor, and with the side-walls and fuel-supply, of the fuel-gate adjustably supported and having its edge reduced at the ends thereof to provide a widened fuel-passage, as set forth.

ECKLEY B. OOXE.

\Vitnesses:

STEWART F. MAOFARLANE, ELLIOTT A. OBERRENDER.

Images