Apparatus for Regulating the Admission of Air to Furnaces.
Year: 1898

page_text: Date of Application, 14th Dec., 1893-Accepted, 21st Jan., 1899
COMPLETE SPECIFICATION.
Apparatus for Regulating the Admission of Air to Furnaces.
I, FRANZ MARCOTTY, of 23, Kleist Strasse, Berlin, in the Empire of Germany,
Merchant, 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:
The various kinds of apparatus hitherto employed for the purpose of admitting
air from above in due quantity to the furnace, after each charging of the latter,
have the disadvantage that the admission of such air occurs after every opening
or closing of the furnace door, whether or not any fresh charging of the furnace
is necessary or intended.
to
of
The object of the present invention is an apparatus which obviates
this disadvantage by enabling the furnace door be opened to the
extent of an angle of about 60° without its being possible for air.
from above to enter the fire place after the subsequent closing
the furnace door. This only happens in fact, when the furnace door is
opened to the extent of a correspondingly larger angle of more than 60°, as is
absolutely necessary for the introduction of the charge. In this way, the admis-
sion of air from above occurs only, after such introduction, and is not effected at
all if the furnace door be opened to the extent of 60° for the purpose of examining
the fire.
In Figures 1 to 4 of the accompanying drawing, one form of this new apparatus
is illustrated.
Fig. 1 represents a front view of a furnace door with regulating arrangement.
Fig. 2 is a vertical section through the middle of the furnace door with the
regulating arrangement partially closed.
Fig. 3 is a similar section with the regulating arrangement open.
Fig. 4 represents a horizontal section through the furnace door.
In the form of the invention illustrated by way of example, it is supposed that
the regulating apparatus consists of a rotary shutter b, fixed to pins or trunnions i
which are seated in the furnace door in ball bearings (see Fig. 4). The air inlet
openings c made in the furnace door, are either opened, or entirely or partially
closed according to the position of the rotary shutter. To the one pin i the tooth
or bevel wheel d is fixed. This wheel engages with another rotary bevel wheel c
on the axis f of the furnace door. The rod g linked to the hub of the wheel e
serves to hold under tension the cataract not shown in the drawing, and which may
be of any desired construction, and on the other hand, when the cataract runs down,
to transmit the motion of the cataract piston to the regulating contrivance. When
the cataract has run down, and before the furnace door is opened, the regula-
ting contrivance takes the position shown in Fig. 2. Instead of the partial closing
of the openings c, as assumed in the present case, the dimensions may, according
to circumstances, be such that the rotary shutter will entirely close the openings.
If the furnace door be now opened, the resistance which the cataract will present
through the arm g to the rotary motion of the wheel e will cause the pin which
has an almost frictionless seating in the ball bearings, to rotate and thereby the
wheel d to run round the wheel e. The wheel dis consequently rotated, and

page_text: thereby the rotary shutter carried up to the position shown in dotted lines (see
Fig. 2). As the rotary shutter here comes against the stop h, the wheel d is firmly
held. If the furnace door be opened still wider, the tooth wheel e will be rotated
and the cataract placed under tension,, the counter pressure of the cataract spring
being overcome. If the furnace door be closed again the arm g will be firmly
held by the resistance of the cataract, so that the wheel d must rotate around e,
thereby carrying the rotary shutter up to the position shown in Fig. 3. In this
way, when the furnace door is shut, the openings c are set free and air can enter
above the fire place. As the cataract runs down, the shutter falls back again into
the position shown in Fig. 2, and thereby confines the upper air to an extent
determined by the position of the cataract..
If the furnace door be not opened for the purpose of introducing a charge, but,
in order to examine the fire, only to the extent of an angle of about 60°, this
turning of the furnace door will not result in influencing the rotary shutter 6 by
the stop nor, consequently will any transmission to e be effected by the wheel d
for the purpose of putting the cataract under tension. Thus, the rotary shutter
will be brought back into its former closing position and the admission of air be
prevented, upon the furnace door being closed, by the wheel d running round
the wheel e.
1 ..
Having now particularly described and ascertained the "nature of my said in-
vention and in what manner the same is to be performed. I declare that what I
claim is:-
1. An apparatus for regulating the admission of air from above to furnaces, the
distinguishing feature of which is that the openings provided for the admission
of the upper air are only opened when the furnace door is opened sufficiently wide
for charging and closed again after the charging has been effected, whilst when
the furnace door is opened, to the extent of an angle of only about 60° for the
purpose of examining the fire, and is then closed, the rotary shutter resumes its
former closing position, such apparatus consisting of a tooth or bevel wheel gear,
one wheel d of which is firmly fixed on the pin or axle of the regulating con-
trivance which is restricted in its movement by a stop h whilst the other wheel e
arranged on the axis of the furnace door, is connected with the piston of a cataract,
in such a manner that, when the furnace door is opened, the wheel d is only
restricted in its movement and the wheel e rotated for the purpose of putting the
cataract under tension, after such door is open to the extent of an angle of
about 60°, but when the furnace door is closed, the wheel e is firmly held by the
cataract under tension and the wheel d rotated for the purpose of opening the
regulating contrivance, substantially as herein set forth.
2. In the apparatus claimed in Claim 1, a rotary shutter b, the pins or trun-
nions of which are seated in ball bearings, for the purpose of diminishing friction,
so that the resistance presented by the cataract, through the arm g, to the rotation
of the wheel e is correspondingly greater owing to the diminished friction resulting
from the movement of the pins or trunnions in the ball bearings.
Dated this 14th day of December 1898
HARRIS & MILLS,
23. Southampton Buildings, London, W.C., Agents.