Improvements in Automatic Draught Regulating Apparatus for Furnaces.
Year: 1896

page_text: Date of Application, 31st Oct., 1896-Accepted, 12th Dec., 1896
COMPLETE SPECIFICATION.
Improvements in Automatic Draught Regulating Apparatus for
Furnaces.
I, ADOLF ANTON of Borgosesus in the Kingdom of Italy, Engineer, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described aud ascertained in and by the following
statement :-
This invention relates to an apparatus for automatically regulating the draught
in furnaces so as to control the amount of air passing through the grate bars.
It is known that good combustion in furnaces requires the admission into the
furnace of a certain quantity of air which varies with the different phases of
combustion being at the maximum when the fuel is just lighting, less when fuel is
in combustion and at the minimum when the fuel is nearly consumed. The want
of air and the superabundance of it upon the grate bars are both contrary to a
good and economical working of the furnace.
The present apparatus regulates the draught of air at the grate bars in a quantity
decreasing from the moment the fuel is charged to that at which it is burnt out.
The apparatus has an alarm bell arranged to indicate the times when it is desirable
to charge fuel.
The apparatus is illustrated in the accompanying drawing in connection with a
steam boiler, in which :-
Fig. 1 is a front elevation of the apparatus.
Fig. 2 is a side elevation.
Fig. 3 is a vertical section on a larger scale of a part of the cylinder with the
piston and valves.
Fig. 4 is a sectional plan of Fig. 3.
Fig. 5 is a view of a boiler showing how the apparatus is applied.
A is a cylinder holding some liquid matter such as oil, glycerine, or the
like, B is a piston attached by ribs C to a block or nut D through which
passes the screwed portion E¹ of a shaft E having at its lower end a valve F,
and at its upper end a lever G whose purpose is to cause the screw E to turn in
the nut D so as to raise or lower valve F. H is a tube screwed to nut D and
surrounding shaft E. I is a frame attached to H having a handle L whose
purpose is to force up and down by hand the piston, M is a half quadrant with
divisions marked on it with which lever G co-operates, M' are two columns attached
to the cylinder cover, and carrying a half quadrant M and a top crosshead M".
N is a loose valve resting upon piston B and closing the ports of same and con-
nected to nut I) by a ring N¹ and ribs N, the ring N₁ surrounding a reduced
portion of the nut. O is a projecting piece attached to frame I. P is a flat bar
attached to the cylinder cover and to the top crosshead M", said bar supporting
a spring alarm bell Q. The tube H at its upper end carries a fork with a pin to
which is attached the rope or chain, which after passing over pulleys is secured to
the damper in the furnace flue. R is a collar attached to tube H for holding
weights, the purpose of which is to counterbalance the weight of damper. The
apparatus being applied to a steam boiler furnace as shown in Fig. 5 when fuel is
charged upon the grate the piston is forced by hand down by means of handle L,
so that the liquid contained in the cylinder under the piston passes through
the ports of same on to its upper side. This movement of the piston through

page_text: tube H and cords or chains will raise the damper so that air to the full amount
passes under the grate and through the fire. When the charging of fuel is
accomplished the valve F is lowered a little by giving a half turn or more to the
lever G. By reason of the weight of the damper the piston will now rise little
by little as the liquid inside the cylinder passes from the upper to the under side
of the piston through the annular space around the valve F, the rapidity of the
movement of piston depending upon the space existing between valve F and its
seat, which space may be varied by means of lever G as a more or less rapid
combustion is required. When the piston has reached the top of cylinder and
the damper is nearly shut the piece O touches the operating parts of the alarm
bell, and the bell gives the signal for a new charge of fuel.
The position of the alarm bell upon the bar P may be varied, the bell being
fixed to it by a screw and winged nut Q' which is movable in a slot Qof the
bar. On P may be marked divisions corresponding to different positions of the
bell in correspondence with different requirements of combustion.
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. An automatic draught regulating device for furnaces comprising a cylinder
containing a liquid and a piston operating substantially as described.
2. In an automatic draught regulating device for furnaces having a piston and
cylinder as described in Claim 1, a valve applied to said piston operated by a
screw shaft, a lever for operating said shaft and a quadrant with divisions marked
thereon so as to regulate the passage of the liquid from one side of the piston to
the other substantially as and for the purpose described.
3. In an automatic draught regulating device for furnaces having a piston and
cylinder as described in Claim 1 the arrangement of the loose valve N, tube H
and handle L for moving the piston by hand, substantially as and for the purpose
described.
4. In an automatic draught regulating device for furnaces having a piston
and cylinder as described in Claim 1, the arrangement of alarm bell attached to
bar P and operated by the movement of tube H and the descent of the damper
substantially as described.
5. In an automatic draught regulating device for furnaces having a piston and
cylinder as described in Claim 1, the arrangement of the counterweighted tube H,
damper and connections operating substantially as described.
6. The construction and arrangement of automatic draught regulating device
for furnaces substantially as described and illustrated.
Dated the 31st day of October 1896.
PHILIP M. JUSTICE,
London, Chartered Patent Agent.