Improvements in Stoves.
Year: 1895

page_text: Date of Application, 12th Aug. 1895-Accepted, 14th Sept., 1895
Improvements in Stoves.
I, HERMANN CARL' OSTERMANN, of 42 Schlägerstrasse, Hanover, in the 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:-
This invention relates to slow combustion stoves in which the fuel is fed into a
shaft or combustion chamber above the grate from the top and becomes ignited by
degrees, the rate of combustion being increased or decreased as desired by regulating
the admission of air, so that the feeding of the fuel need only take place at long
intervals. By the complete or nearly complete closing of the doors of such
combustion stoves as constructed hitherto, the admission of air is limited sometimes
to such an extent that the fire is only just being maintained. In consequence the
gaseous products of incomplete combustion accumulate in the upper part of the
stove, because the suction of the chimney nearly ceases. This accumulation causes
slight explosions, which will be observed by rattling noises which accompany
them. Besides, gases thus accumulated will escape from the stove into the room,
vitiating the air therein.
The object of this invention is to construct slow combustion stoves so as to avoid
these disadvantages and at the same time to ventilate the room by sucking in air at
a time when the combustion is almost interrupted.
In order that my invention may be the better understood, I now proceed to
describe the same, reference being had to the accompanying drawings and to the
letters and figures marked thereon.
A stove of ordinary size is shown in Figures 1, 2, and 3, while a stove for large
rooms is shown in Figures 4, 5 and 6, drawn to a smaller scale.
Figure 1 is a vertical section of the stove of ordinary size.
Figure 2 is a horizontal section thereof upon the line I-I, Figure 1.
Figure 3 is a horizontal section thereof upon the line Il-II, Figure 1.
Figure 4 is a vertical section of the stove for large rooms.
Figure 5 is a horizontal section thereof upon the line III-III, Figure 4, and
Figure 6 is a horizontal section thereof upon the line IV-IV, Figure 4.
A is the shaft or combustion chamber which is filled to the top with fuel. B is
the ash chamber. c is the fire grate and c¹ is the side grating.
The fuel is fed into the small stove by means of an orifice in the upper part U
which is provided with a short cylinder land can be closed by a flap or slide. From
the side of the upper part of the stove branches off the pipe r, which leads directly
into the chimney or to a flue leading thereto.
The combustion chamber is lined with fire bricks into which are recessed vertical
channels v, Figures 1 and 2. This may be done by constructing the lining of
recessed fire bricks or slabs. The vertical channels v communicate with the
combustion chamber by transverse channels g, slanting downwards.
An annular channel K is separated from the ash chamber B by a circular
partition w. The annular channel K has orifices o through which it communi-
cates with the outside air and which are closed either wholly or partially by slides
or valves o¹.
When the fire in the stove is burning freely, the slides or valves o' are closed and
the doors of the ash chamber B opened.

page_text: If on the other hand the stove is to radiate as little heat as possible and the
fire is only to be maintained so as not to be extinguished, the doors to the ash
chamber and fire grate are completely closed and the orifices o of the annular
channel K are opened more or less. In this case the suction of the chimney causes
the air in the room to ascend in the vertical channels and part of it enters
through the slanting channels into the shaft or combustion chamber A and
supplies the fuel with the oxygen necessary for the maintenance of combustion,
while the other part of the air enters direct into the upper part of the stove and
escapes thence to the chimney. Gases of combustion can therefore not accumulate
in the stove. Further, though the combustion may be maintained only slightly,
a comparatively large removal of air takes place from the room.
The stove, Figures 4, 5 and 6, designed for large rooms differs from that of
ordinary size, described before, in the following respects. On the sock-shaped
ash chamber B is situated a mantle T which extends beyond the stove proper and
is closed by the flap or cover T'. The mantle T is provided with holes e at the top
and bottom of its side and through its cover and is designed to accelerate the
heating of the air in the room. This is effected by the cold air entering through
the lower holes e into the space between the mantle and the stove, ascending therein
and escaping through the upper holes. On account of the mantle T the feeding
orifice in this case is not situated in the cover of the stove, but at the side and is
accessible through a door in the mantle the shaft or combustion chamber A of this
stove is closed by a box like cover P provided with ribs on the top and assisting in
the heating of the air. In this case the vertical channels » communicate also with
9 and
the flue or combustion chamber A through the slanting transveise channels
also direct with the pipe leading to the chimney. This communication with the
piper takes place by the highest transverse channel 9 being above the fuel in the
flue or combustion chamber A and the vertical channel v arranged on the same side
as the pipe r, entering into the recess in the lining which leads to the pipe r.
The transverse channels instead of slanting downwards may be arranged
horizontally. However, the first named arrangement has the advantage that it
prevents more effectively the fuel from falling into the vertical channels v.
If the fuel used is of such a kind that the fire in the stove becomes easily
extinguished, when no air at all is fed to the fire grate, it is advisable to omit the
partition w between the annular channel K and the ash chamber B, thus doing
away with annular channel altogether, so that the vertical channels ascend from
the ash chamber. In this case when the combustion is to be reduced, the door of
the ash chamber is not quite closed, so that air may pass from the receptacle partly
below the fire grate and partly into the vertical channels.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
で
1. A slow combustion stove with vertical channels recessed into the refractory
lining of the shaft or combustion chamber A communicating at their lower ends
with an annular channel K provided with closable orifices O, in their middle part
with the shaft or combustion chamber A through transverse channels q and at their
upper ends with the upper part of the stove; so that when the doors of the stove
are closed to limit the combustion air may be drawn by means of these channels
towards the chimney, partly through the shaft or combustion chamber and partly
direct to the chimney, in order to prevent accumulation of gases of combustion in
the stove and to ventilate the room substantially as described.
2nd. The modification of the stove as claimed in Claim 1, in which the annular
channel K is omitted and the vertical channels v communicate direct with the ash
chamber, so that when the combustion is reduced air is sucked in, partly below the
fire grate, partly through the vertical channels, substantially as described.
3rd. A stove as claimed in Claims 1 and 2 in combination with a mantle T

page_text: surrounding it, through the lower orifices e of which air enters from the room,
and returns into the room through the orifices e at the top in order to accelerate
the heating of the room by means of this circulation, substantially as described.
Dated this 12th day of August 1895.
FELL & WILDING,
Agents for the Applicant.