D. M. DUNCAN COMBUSTION CHAMBER OF BOILER FURNACES March l4., 1924.
l Filed May 8, 1922 t I' As Patented Mar. 4, 1924.
A oNiTEofsrrEs DAVIDv MILNEDUNCAN, OF TORONTO, ONTARIO, CANADA.
COMBUSTION CHAMBER OF BOILER FUBNACES.
Application led May 8,
To all whom t may concern.'
Be it known that I, DAVID MILNE DUNCAN, a subject of the King of Great Britain,vand
` resident of 152 Bartlett Avenue, in the city of Toronto, in the Province of Ontario, in the Dominion ofl Canada, have invented certain newand useful Improvements in Combustion Chambers of Boiler Furnaces, of which the following is a specification.
rlhe invention relates to limprovements in the combustion chamber of boiler furnaces as described in the present specification and shown in the accompanying drawing that forms a part of the same.
The invention appertains moreparticularly to combustion chambers for horizontal boilers having an external heating surface, such invention being characterized by a series of transverse grilles disposed to the rear of the grate in the path of the gases and a screen of spaced brick-work; this construction radiating and absorbing the heat thereby preserving an igniting temperature sufficient to effect combustion of unburnt and partially consumed gases; and, furthermore, to precipitate such gases, thus Vretarding their progress until complete combustion is eected. v
The object of the invention is to provide greater efficiency and economy in combustion of fuel in a boiler furnace by auxiliarating incomplete and imperfect combustion of the gases, the enhanced combustion obviating loss of heat and deficiency prevailing in a furnace due to the escape of unconsumed gaseous combustibles.
Referring to the drawing, Figure 1 is a longitudinal sectional view of the boiler.
Figure 2 is a transverse sectional view of the grilles taken on the line 5 5 of Figure 1. 1
Figure 3 is a further transverse sectional view taken on the line 6--6 of Figure 1 illustrating the screen or baie wall.
Figure 4 is a cross-sectional view taken on the line 7 7 of Figure 2, illustrating the arrangement of the grille.
Figure 5 is a fragmentary view of the screen showing the bricks disposed with an intervening space.
Like numerals of reference indicate corresponding parts in each figure.
In the drawing, 1 designates the boiler proper of conventional construction having the usual furnace grate 2 disposed subjacent the front end thereof and provided with the `face of the boiler.
1922. serial No. 559,456,
necessary fittings, said grate being partially f' borne 4by the bridge 3 which keeps the hot gases in close contact with the heating sury The gasesv as they are generated pass to the rear of the combustion chamber and are deflected by the wall 4 and returned through the tubes of the boiler. to the flue orv chimney for subsequent discharge. The a'foregoing being ofvcustoma'ry construction and well known to the art.`
z 5 arethe grilles of which there are av plurality, such being -arranged transversely and successively from a point slightly to the rear of the bridge 3 and supported a suitable distance from the furnace bottom by angle irons 6 which may either have their ends embedded in the opposing walls or be sustained by stools as at 7, thus providing a substantial area for the passage of the gases below said grilles. The top of the grilles terminate a short distance from theheating surface of the boiler as at 8.
Each grille comprises alternate courses of spaced bricks longitudinally disposed as at 9 and a double spaced row of abutting bricks as at 10 transversely arranged, thus forming a vertical space having communication with the top and bottom of the combustion chamber and also with the intermediate portion 1 thereof through the side openings.
The grilles are constructed of a heat absorbing material, preferably .of vitried brick, and are not ybonded or otherwise Vcemented by mortar.
11 is the screen or baffle wall disposed about Vthe rear extremity of the boiler proper interposing the grilles and the rear wall 4, said screen or baffle wall being supported by cross members 12 similar to the grilles but'on a slightly lower plane thereto.
The screen or baiie wall is also construct- Y the heating surface of the boiler proper. A
The less buoyant gaseous particles which comprise theunignited elements andv constituents deficient in oxygen are retarded by their impingement upon the grilles deflecting and precipitating same downwardly,
through the spaces or voids therein, thus` causing some of the slow burning particles toV be completely consumed by their retention between the heated bricks andV others by their deflection.
What I claim is `l. The combination in a combustion chamber of a boiier furnace, of a transverse screen removed from the furnace .bottom constructed of isolated brick-work forming small spaces for vthe passage of hot gases, and spaced grilles interposing the said screen and a gate bridge, said grilles being removed from the furnace bottom, each grille comprising alternate courses of spaced longitudinal bricks and a double row of spaced transverse bricks.
2.. In'a combustion chamber of al boilerV furnace, a series of transverse grilles removed from the :furnace bottom, each individual grille comprising alternate courses of spaced bricks longitudinally disposed and a double row of transverse rbricks having abutting ends,l and a space interposing said double row ofxbricks; said individual grilles each being independently supported by angle irons disposed subjacent each'of the transverse row of bricks,V said angle irons not being of a greater Width than the same in ordernot to prevent precipitation of carbon.
DAVID VVMinus DUNCAN. Y