US549948A - Grate for steam-boiler furnaces - Google Patents

Description

(No Model.) 3 Sheets-Sheet 2.

J. VAN DEVELDE. GRATE FOR STEAM BOILER FURNACES, &c.

Patented Nov. 19, 1895.

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JOHN VAN DEVELDE, OF CLEVELAND, OHIO.

GRATE FOR STEAM-BOILER FURNACES, C.

SPECIFICATION forming part of Letters Patent No. 549,948, dated November 19, 1895.

Applioation filed OctoberlZ, 1594.

To all whom it may concern:

Be it known that I, J OHN VANDEVELDE, a citizen of the United States, residing at Cleveland, in the county of Ouyahoga, State of Ohio, have invented certain new and useful Improvements in Steam-Boiler Furnaces, of which the following, with the acco1npanying drawings, is a specification.

My invention relates more especially to steam -boiler downward-draft furnaces in which hollow grate-bars or tubes, through which water from the boiler circulates, are used.

The object of my invention is an improved construction of steam-boiler furnaces employing tubular grate-bars connected with a water-chamber that in turn is connected with the boiler, whereby a more perfect combustion of fuel is obtained and the steam-generating capacity of the furnace is increased.

lVith these objects in view my invention consists in the novel features of construction and combination of parts described herein and defined in the claim.

In the drawings, Figure 1 is a longitudinal section of my invention. Fig. 2 is a front view. Fig. 3 is a central longitudinal section of the water-chamber. Fig. 418 an enlarged longitudinal section of the front end of the hollow grate-bars and inolosed circulation tube. Fig. 5 is an enlarged perspective of a broken section of the front end of the circulation-tube, and Fig. 6 is a cross-section of one of the hollow grate-bars and the inclosed circulation-pipe on the line 6 6 of Fig. 4. Fig. 7 is a longitudinal section of a modified arrangement of my invention.

In the accompanying drawings, A is the boiler, which is of the usual construction, having flues therethrough longitudinally, which communicate with the space below the smokestack A.

B is the furnace outer wall, which is of any desired construction, and O is a baffle-wall extending across the furnace from the boiler to the floor of the furnace. There is an opening 0 through the baffle-wall,which forms an escape for the products of combustion from the fire.

D is a division-wall.

E is awater-chamber which preferably corresponds to the widthof the grate, and it Serial No. 525,665. (No model.)

opens into the boiler A through the connection F.

The lower upward-burning grate G, of any construction, is supported by the bafile-wall O and the flange or fillet h of the furnacefront H.

The space I below the grate G is the ash-pit.

I I are the doors to the ash-pit.

The upper downward-burning grate consists of a series of tubular or hollow bars K K arranged horizontally with a slight slant, as illustrated. These tubular bars are closed at their front ends by screw-caps k 70, and their back ends are screwed into the front side of the water-chamber E. The front ends of the tubular bars K are supported by flanges h and h. The space L between the upper and the lower grates forms a combustion-chamber.

M lWI are fire-doors that open to the firespace above the lower grate and to the con1- bustion-chamber.

N N are fire-doors that open to the firespace above the upper grate.

Below the upper fire-holes there is preferably placed a fillet h, over which the stoking is done for the upper fire, and limits the stoking back of said fillet to protect the front ends of the tubular grate-bars K.

M are doors which open access to the cap ends 70 for repairs or other purposes.

WVithin the tubular bars K K are circulation-tubes P P, the front ends of which are held free of the inside of the caps k by means of the braces or supports 19, and they are held free of the sides of the tubular bars K by means of the braces 10. The circulating-tubes extend into the water-chamber E, preferably to a point back of the center thereof, as illustrated.

I have illustrated two horizontal series of suppplemental tubular bars K, having therein circulating-tubes P, the supplemental tubular bars opening into the water-chamber E and having their front ends closed by caps 70, the circulating-tubes P being held free of the inside of the tubular bars K and extending into the water-chamber E, in all respects like the tubular bars K and the circulatingpipes P; but they extend forward only so far, or not so far, as the baffle-wall G. These'may be employed to increase the tubular heatingsurface or they may be omitted.

In the use of my invention stoking is done through the doors N N for the upper grate and through the doors M M for the lower grate. The space L between the upper and lower grates forms a combustion-chamber. Air passes downward through the upper grate, as indicated by the arrow 7', and upward through the lower grate, as indicated by the arrow 8. The draft passes through the escape C of the baffle-wall C, up among the tubular bars K and K, around the connection F, and through the boiler-fines, as indicated by the arrows t t. The colder water from the boiler finds its way down the back side of the connection F to the outer back part of the water-chamber E. The cooler water then passes into and through the circulating-tubes P P and comes back heated to a higher degree around the circulatingtubes and back to the boiler through the front part of the water-chamber E and the connection F. This circulation is induced by the Varying temperature of the water and the heat applied to the tubular bars K and K.

The arrangement of my invention, as illustrated by Fig. 7, may be employed when a less tubular heating-surface is required than by either of the constructions hereinbefore referred to. The water-chamber E is placed immediately back of the fire-box at the wall 0, and the connection F is connected to the boiler immediately above. The tubular gratebars K and circulating-tubes P are in all respects like those hereinbefore described. As the boiler-front and fire and ash doors of the modification are the same as in the other form illustrated, the same parts are given the same reference characters in Fig. 7 as in the other figures.

In the form illustrated by Fig. 7 the draft passes through the escape 0 along the under side of the boiler, and through the boilerflues, as indicated by the arrows u in said figure.

\Vhat I claim as my invention, and desire to secure by Letters Patent, is-

The combination, in a steam-boiler furnace, of a water-chamber having an opening for connection with a boiler, a bathe-wall extending laterally through the furnace from the boiler to the floor of the furnace, an escape opening through the bafiie-wall, an upward burning grate extending from the bafile-wall below the escape opening thercthrough forwardly to the furnace front, a downwardly burning grate consisting of tubular grate bars, said tubular grate-bars being closed at their front end and opening into said waterchamber at their back end, and circulation tubes having both ends open, said circulation tubes being within the tubular gratebars and projecting into the water chamber, substantially as specified.

In testimony whereof I ailix my signature in the presence of two witnesses.

JOHN VAN DEVELDE. \Vitnesses:

J. A. OSBORNE, JNO. G. COMPTON.

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