Improvements in Smoke-consuming Furnaces.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Smoke-consuming Furnaces.
I, WILHELM OTTO THOST of Zwickau, in the Kingdom of Saxony, German
Empire, Manufacturer do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :—
My invention relates to a furnace arrangement which ensures complete and
smokeless combustion of the fuel, and the working of which is very simple and
efficient.
My invention consists in a grate composed of two sets of grate bars which are
supported by air-tubes, said grate being placed on the incline, whereby the grate
surface is considerably increased. The angle of inclination is dependent on the
kind of fuel used and is in every case such as to cause the latter to be equally
distributed when placed upon the ridge of the grate.
For stoking I employ a special trough-shaped shovel having the same length as
the grate itself.
The better to make my meaning clear I will proceed to describe a furnace
constructed and operated according to my improvements, referring to the accom-
panying drawing, on which:
Fig. 1 is an end elevation of the furnace, partly in section.
Fig. 2 is a longitudinal sectional elevation of the same.
Fig. 3 is a cross-sectional elevation of a modification.
Fig. 4 is an end elevation of the same.
Fig. 5 is an end elevation of another modification.
Fig. 6 is a cross-sectional elevation of the same.
Similar letters denote similar parts throughout the several views.
The front plate of the furnace is provided with swing doors B, with doors D
and with openings C covered by panes of mica. Air-tubes E E pass under the
whole length of the grate F. The latter is in Fig. 1 formed with two inclines,
and with four of them in the modification illustrated by Fig. 3. The grate F is
supported by the air-tubes E. In the modification shown by Figs. 5 & 6 the
grate F is formed with two inclines, the lowest point being however in the middle
of the furnace. Instead of the front doors B 1 provide lateral doors G G in
this modification. The other parts, the boiler A and its fittings, are constructed
in the usual manner and do not form part of this invention.
The shovel H which I employ for my improved furnace is shown at Fig. 2.
The same is of the trough-shape illustrated by the drawing, so as to permit of
its introduction through the swing-doors B, and of such length, as to reach to the
back end of the grate F when fully pushed in through said doors. In the modifi-
cation Figs. 5 & 6 I need not employ a shovel of the special construction shown,
but may use a shovel of the ordinary kind.
The manner of tending the fire and of using the furnace is the following:
The shovel H being charged with fuel is passed through the swing doors B into
the furnace and emptied by turning it around on its axis. The sharpened forward
end of the shovel H, when the same is pushed into the furnace, removes the fuel
lying on the ridge of the grate. The swing-doors B are constructed in such
manner that they open automatically upon introducing the shovel H and close
automatically when the shovel is withdrawu. It will be seen by a glance at Figs. 1
to 4 that the shovel is inserted over the highest point of the grate F, in order that
the fuel may be distributed equally on all inclines. Through the openings C,
having panes of mica, the fire may be watched continually. The slag is removed
through the doors D. As the continual opening and closing of the doors is

page_text: rendered unnecessary by the described arrangement, cold air does not enter the
furnace and a uniform and economical combustion of the fuel is thereby ensured.
It will be seen that the distribution of the fuel over the surface of the grate is very
casy and requires no special work and trouble on the part of the stoker.
Another advantage of the described manner of charging the furnace is that the
fresh cold fuel is not placed so as to cover the glowing fire, but as to lie beside
the same, whereby a more regular and less impetuous combustion is obtained.
The glowing fire is not removed and is therefore able thoroughly to consume
smoke and soot.
The heating effect of the furnace is a very powerful one, and has been ascertained
to yield, when employed for a boiler, a production of steam about 10% larger than
that obtained with other systems of furnace.
The consumed fuel by degrees slides down the inclined surfaces of the grate, and
the clinker or scoria accumulates at the lowest parts of the same, whence it may be
easily removed through the doors D, as already mentioned.
By means of the air-tubes E heated air is led behind the fire-bridge, where it
mixes with the gases of combustion and prevents the formation of smoke and soot.
The quantity of air supplied through these tubes E may easily be regulated by
closing the front ends of a number of the same.
The improved furnace which I have described hereinbefore is also particularly
advantageous because the work of the stoker is easier, less tiring and more
expeditious, and the fire is rendered less dependent upon the skill and good will of
the stoker.
Though I have described the furnace as applied for heating a boiler, I may of
course also employ the same for stoves or for any other purpose where it may be
used with advantage.
I do not confine myself to the several forms of construction shewn and described,
and the same may be altered to suit special circumstances, without departing from
the nature of my invention.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. A smoke consuming furnace having a suddle-shaped grate the bars of which
are placed transversely to the axle of the furnace and supported by air tubes
extending longitudinally, for the purpose as described.
2. The trough-shaped shovel H, having the same length as the grate, substantially
as shown and described with reference to Fig. 2 of the drawing.
Dalin 17th 1000
WILHELM OTTO THOST,
By Fredk. Walker,
11, Furnival Street, Holborn, London, E.C., Agent for the Applicant.