Improvements in or relating to Obtaining More Perfect Combustion in Steam Boiler Furnaces and Flues, and in Apparatus employed in connection therewith.
Year: 1889

page_text: Date of Application, 30th Oct., 1889
Complete Specification Left, 27th Aug., 1890-Accepted, 27th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in or relating to Obtaining More Perfect Combustion
in Steam Boiler Furnaces and Flues, and in Apparatus employed
in connection therewith.
I, JOHN COUSINS of 62 Fentonvilla Street, Sharrow, Sheffield in the County of
York, Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to obtaining more perfect combustion in steam boiler furnaces
and flues; thereby effecting a considerable saving in the cost of fuel and reducing the
smoke to a minimum.
This I accomplish by exposing the incandescent fuel, and the combustible matters
passing away to the chimney, to a second body of heated air admitted at or near the
bridge.
It is found that if the volume of air be greatly deficient of that necessary for
perfect combustion, smoke or soot will be formed in the remoter ends of the flucs,
the adherence of which to the boiler surfaces becomes a cause of loss of effect, and if
the volume be greatly in excess, the heat of furnace is reduced, and may be so to such
an extent as to cause even imperfect combustion, and a great volume of air is uselessly
heated and discharged by the chimney. I therefore prefer to admit the air in
adjustable volumes at the bridge (through a channel or passage formed therein) where
it can mingle as completely as possible with the gases passing towards the chimney,
and this being the hottest part of the furnace, the combustible matters are, as far as
possible, consumed, together with the particles of carbon suspended therein, thus
reducing the emission of smoke from the chimney.
The air so admitted is preferably heated by first passing beneath the fire bars
of the furnace, and is then admitted through an orifice into the channel in the
bridge.
The said admission orifice is controlled by a regulator or valve adapted to adjust
the size of the opening or entirely close it to the passage of air, and it is operated
either by a hand lever, or by an apparatus comprising a cylindrical or other
shaped vessel or container having a bucket or cup shaped piston of rather smaller
diameter or size than the internal dimensions of the vessel aforesaid, and so adapted
that there is a space between the sides of each. The bucket is suspended by a
vertical rod coupled to the connecting rod which operates the controlling valve. The
When the
said container and bucket are filled with a suitable quantity of water.
draught is abnormally great, the door or valve will have a tendency to close the
opening, and reduce the volume of air, thereby lifting the bucket, and causing the water
to flow out, through a small hole, into the container, thereby reducing the weight of
the bucket, which thus acts as a 'balance or counterweight. When the draught is
abnormally low, the door has no longer a tendency to close the opening, so that the
bucket gradually sinks, opening the door wide for the admission of a larger volume
of vital air, and it is assisted in so doing by the weight of the water which flows into
it by the hole aforesaid or over its sides.
The appliance may be adapted to be operated by a hand lever as well as
automatically.
If desired, the said device may comprise a cylinder supplied with steam from the
boiler and a piston, the latter so constructed as to close or open the air valve when
the steam in the boiler respectively exceeds or is less than a given pressure per square
inch.
.
I sometimes provide a second bridge in the furnace at the back of the hollow

page_text: bridge, adapted to direct the gases, etcetera, downwards so as to more thoroughly
mix them with the air.
Dated this 29th day of October 1889.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Obtaining More Perfect Combustion
in Steam Boiler Furnaces and Flues and in Apparatus employed
in connection therewith.
I, JOHN COUSINS, of 62 Fentonvilla Street, Sharrow, Sheffield, in the County of
York, Engineer, 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 obtaining more perfect combustion in steam boiler
furnaces and flues, thereby effecting a considerable saving in the cost of fuel and
reducing the smoke to a minimum."
This I accomplish by exposing the combustible matters, passing away to the
chimney, to a second body of heated air admitted at or near the bridge.
It is found that if the volume of air be greatly below that necessary for perfect
combustion, smoke or soot will be formed in the remoter ends of the flues, the
adherence of which to the boiler surfaces becomes a cause of loss of heating effect,
and if the volume of air be greatly in excess, the heat of the furnace is reduced, and
may be so to such an extent as to cause even imperfect combustion, a great volume of
air being thus uselessly heated and discharged by the chimney. I therefore prefer
to admit the air in adjustable volumes at the bridge (through a channel or passage
formed therein) where it can mingle as completely as possible with the gases passing
towards the chimney, and this being the hottest part of the furnace, the combustible
gases are, as far as possible consumed, together with the particles of carbon suspended
therein, thus reducing the emission of smoke from the chimney.
The invention may be described in detail as follows, reference being had to the
accompanying drawings, in which
Figure 1 is a front elevation of a "Lancashire" boiler having one of its furnaces
fitted with my improvements.
Figure 2 is a longitudinal vertical section through said furnace, the air regulating
apparatus being also partly in section.
Figure 3 is a similar section showing a slightly modified form of apparatus.
A is the boiler furnace, B the firebars, C the bridge, D the flue. The air admitted
to the fluc as above described is, by preference, first heated by passing below the
firebars, either by a pipe E as in Figure 3, or otherwise. The said pipe may enter
the front of the bridge, or it may be extended through the same into the furnace and,
returning upon itself, enter the back of the bridge, as shown in Figure 3. The air
is admitted either directly from the ashpit F, as in Figure 2, or by the pipe E
aforesaid through an orifice G into the channel or recess H of the bridge, whence
it escapes into the flue by suitable apertures J, and there meets with the heated gases
and suspended matter coming from the furnace.
The admission orifice G is controlled by any suitable regulator or valve, adapted to
adjust the size of the opening or entirely close it to the passage of air. In the arrange-
ment shown in Figures 1 and 2, the valve is simply a hinged plate K which may be
operated either by a hand lever, or by an apparatus such as the following:
A cylindrical or other shaped vessel or container L is provided with a bucket or
cup shaped piston M of rather smaller diameter or size than the internal dimensions
of the vessel aforesaid, so that there is a space between the sides of each. The bucket
is attached to a vertical rod M¹ which is suspended from an angle or other suitable

page_text: lever N coupled to the connecting rod P which operates the controlling valve K.
The said container and bucket are filled with a suitable quantity of water. It is
preferable that the water in the vessel should not stand at a higher level than the lip
of the bucket when the latter is in its lowest position. When the draught is
abnormally great it will have a tendency to move the door or valve inwards and so
to close the opening G, and reduce the volume of air. The inward movement of the
valve lifts the bucket M and causes part of the water to flow out, through a small
hole m, into the container, thereby reducing the weight of the bucket, which thus
acts as a balance or counterweight, and prevents unduo vibration in the plate K.
When the draught is abnormally low, the door K has no longer a tendency to move
inwards and close the opening, so that the bucket gradually sinks and opens the
door wider for the admission of a larger volume of air. The opening of the door
is assisted by the weight of the water which flows into it by the hole m aforesaid, or
over its lip.
The appliance may be adapted to be operated by a hand lever as well as automatically,
the hand lever being formed, in the example shown, by an extension n of the lateral
arm of the angle lever N.
If desired, the said air regulating device may comprise a cylinder, supplied with
steam from the boiler, and a piston, the latter being so connected with the air valvo
as to close or open the same when the steam in the boiler exceeds or is less respectively
than a given pressure per square inch.
I sometimes provide a second bridge Qin the furnace at the back of the hollow
bridge Cand adapted to direct the gases, etcetera, downwards so as to more thoroughly
mix them with the air.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is :-
1. The combination with the perforated bridge of a boiler furnace adapted to
deliver air into the flue as described, of an automatic air regulating device, adapted
to regulate the air supply in accordance with the speed of the draught or the
pressure of steam in the boiler, substantially as and for the purpose set forth.
2. An air regulating device applicable for use in connection with steam boiler
furnaces and flues, said device consisting of a valve or door controlling the air
admission orifice and adapted to be closed more or less by the impact of draught of
abnormal strength and to open should the draught fall below the normal point, in
combination with a buffering device so formed as to act strongly against violent
movements of the valve, but gradually and evenly give way against a continuous
force and allow a gradual movement in the reverse direction on the removal of that
force, substantially as described.
Dated this 6th dow of Acest 1800
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.