IMPROVEMENTS IN SMOKE-CONSUMING OR SMOKE-PREVENTING FURNACES
Year: 1876

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN SMOKE-CONSUMING OR SMOKE-PREVENTING FURNACES."
A communication from abroad by Charles Bayley Bryant, of Stoneham,
Henry Young (junior), of Woburn, and Theophilus King (junior), of Quincy,
all in Massachusetts, United States of America.
Sealed the 21st December 1876, and dated the 2nd November 1876.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 2nd November 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN SMOKE-CONSUMING OR SMOKE-
PREVENTING FURNACES." A communication from abroad by Charles Bayley Bryant,
of Stoneham, Henry Young (junior), of Woburn, and Theophilus King (junior),
of Quincy, all in Massachusetts, United States of America.
This Invention has for its object to promote the combustion of smoke and gases
in a furnace, thereby intensifying the heat and economizing fuel; and comprises the
construction of the bridge wall of a furnace with one or more flues or interior
passages communicating with the external air, and with a series of discharge orifices
at or near the top of the wall, through which the air is emitted to impinge upon
and become thoroughly commingled with the smoke and gaseous products of com-
bustion as they pass over into the combustion chamber, whereby their perfect
ignition and consumption isensured.
The said Invention also comprises making the upper surface of the bridge wall
convex in the direction of its width, to correspond with the natural curvature of
the currents of smoke and gases, whereby their passage over the top of the wall is
facilitated.
It also comprises the construction of the combustion chamber with its bottom
elevated to a point a little below the top of the bridge wall and above the level of
the grate bars, whereby the smoke and gases are kept from descending and are
maintained for a longer time in contact with the currents of air emitted from the
discharge apertures in the bridge wall, thus ensuring a more thorough and perfect
commingling of the air and gases than would occur with the ordinary construction.
(Davies 31

page_text: It furthermore comprises the making of the bottom of the combustion chamber of
a boiler furnace concave, whereby the flame is caused to be projected upward at its
sides and rear end to strike the boiler more forcibly and effectively than would be
the case if the bottom of the combustion chamber was perfectly fiat.
the case in the bottom of the combustion Civer was perfectly mat,
DESCRIPTION OF THE DRAWING.
Figure 1 is a longitudinal vertical section through a steam boiler furnace, con-
structed in accordance with this Invention.
Figure 2 is a perspective view of the interior of the same, the boiler and upper
portion of the brickwork being removed.
Figure 3 is a transverse vertical section through the bridge wall on the line x, x,
Figure 1.
Figure 4 is a transverse vertical section through the combustion chamber on the
line y, y, Figure 1.
Figure 5 is a section on the line 2, 2, of Figure 3.
A represents the furnace; B, the boiler; a, the grate bars; b, the ash-pit; C, the
bridge wall; and D, the combustion chamber. Extending longitudinally under the
centre of the floor of the ash-pit is an air passage c which communicates with two
flues or passages d, d, formed within the bridge wall C, as seen in Figure 3, and
from the top of each of these flues & extends a small passage e (Figure 5 and dotted
in Figure 3), which terminates in a discharge orifice fin the top of the bridge wall,
the passages e being inclined upward at an angle of about 45° and also slightly
inward toward the centre of the combustion chamber. The external air first enters
the passage c and thence passes into and up through the flues d, d, issuing from the
discharge orifices f, f, in streams which impinge upon and become thoroughly
commingled with the smoke and gaseous products of combustion as they flow over
the top of the bridge wall into the chamber D, and by thus locating the discharge
orifices fat or near the top of the bridge wall, instead of at the rear thereof, the
jets or streams of air are caused to so impinge upon the smoke and gases as to effect
their ignition at the point best calculated to produce the most advantageous
results, and the smoke and gases are thereby caused to be almost entirely consumed
within the combustion chamber, thus intensifying the heat and effecting a great
saving in fuel. The air passage c is provided at its outer end with a door g, by
means of which the quantity of air admitted to the flues & and issuing from the
discharge orifices f can be regulated as desired. The air in its passage through the
flues & becomes partially heated, as is desirable, before being mixed with the smoke
and gases, and it also tends to cool the bridge wall and prevent its rapid destruction
by the intense heat to which it is exposed. The number of flues or air passages
within the bridge wall may be varied, a single one only or more than two being
employed, as preferred, and any desired number of discharge orifices ƒ may be
provided in or near the top of the bridge wall. The upper surface of this wall C
is made convex in the direction of its width, this form corresponding to the natural
curvature of the currents of smoke and gases and facilitating their passage over the
top of the wall, as no obstructing corners or angles are presented. The bottom h
of the combustion chamber D instead of being on or nearly on a level with the
floor of the ash-pit is elevated, to bring it almost up to the level of the upper edge
of the bridge wall and above the level of the grate bars, by which construction the
volume of smoke and gases is prevented after passing over the top of the bridge
wall from descending out of the reach of the streams of air emitted from the
discharge orifices f, and the gases and the like are thus kept in contact with the
air for a much longer time than would be the case if the bottom of the combustion
chamber was not elevated, and consequently the air is caused to be more thoroughly
and perfectly mingled with the smoke and gases, the combustion of which is by
this means promoted to a great extent.
The bottom h of the combustion chamber is made concave, as seen in Figures 1, 2,
and 4, this form giving an upward direction to the flame at the sides and rear end

page_text: of the combustion chamber, and causing it to be projected against the boiler more
forcibly and effectively than would be the case were the bottom h perfectly level, as
heretofore. is an aperture closed by a door k, through which access can be had to
the interior of the combustion chamber for the purpose of freeing it from dust and
cinders.
Boiler furnaces already constructed may be provided with these improvements at
a moderate cost, there being no necessity for resetting the boiler; and the said
Invention may be used in connection with any furnace to which it can be advan-
tageously applied.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it understood
that I claim,
The bridge wall C provided with a flue or flues or interior passage or passages
communicating with the external air and with a series of discharge orifices ƒ at or
near the top of the wall, through which the air is emitted to commingle with the
smoke and gaseous products of combustion, in the manner and for the purpose set
forth.
Also the bridge wall C having its upper surface convex in the direction of its
width, as and for the purpose specified.
Also the combustion chamber D having its bottom elevated to bring it nearly up
-to the level of the upper edge of the bridge wall and above the level of the grate
bars, as and for the purpose set forth.
Also the combustion chamber D provided with a concave bottom, as and for the
purpose specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Second day of November, in the year of our Lord One
thousand eight hundred and seventy-six.
W. RUB, LAKE.
(L.S.)