IMPROVEMENTS FOR THE MORE EFFECTUAL COMBUSTION OF FUEL AND GENERATION OF STEAM IN FURNACES, PARTLY APPLICABLE TO OTHER FIRE- PLACES
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery.
Lane, in the County of Middlesex, Patent Agent, for the Invention
of "IMPROVEMENTS FOR THE MORE EFFECTUAL COMBUSTION OF FUEL AND
GENERATION OF STEAM IN FURNACES, PARTLY APPLICABLE TO OTHER FIRE-
PLACES."A communication from abroad by Daniel Thomas Case-
ment, of Painesville, in the County of Lake, and State of Ohio,
United States of America.
.
COMPLETE SPECIFICATION filed by the said Alexander Melville Clark,
at the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 6th January 1874, pursuant to the 9th Section
of the Patent Law. Amendment Act, 1852.
Declaration, on the oth January 1874, pursuant to the Stm Dection
of the Patent Law. Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
5
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.

page_text: FURNACES, PARTLY APPLICABLE TO OTHER FIRE-PLACES," and have petitioned
Her Majesty to grant unto me, my executors, administrators, and
assigns, Her Royal Letters Patent for the same, and have made solemn
Declaration that it has been communicated to me from abroad by
Daniel Thomas Casement, of Painesville, in the County of Lake, and
State of Ohio, United States of America.
NOW KNOW YE, that I, the said Alexander Melville Clark, do hereby
declare that the following Complete Specification, under my hand and seal,
fully describes and ascertains the nature of the said Invention, and in
what manner the same is to be performed, in and by the following
statement, reference being had to the accompanying Sheet of Drawings,
and to the letters and figures marked thereon (that is to say) :-
:-
This improved method of burning fuel consists in causing the gases
and other products rising from the fire to pass between and around balls,
blocks, or broken pieces of metal or any other substance in any approved
form, adapted to be intensely heated from the fire below, and also
adapted to cause the said products to come in direct contact with the
hot surface of the balls or blocks as they pass up through them, by
which in practice such perfect combustion is effected, that all the
particles passing off as smoke in other furnaces, except during a short
time before the balls get properly heated when starting the fires, will be
so perfectly consumed that no smoke will be perceptible at the flues, and
the heat thus stored in the balls will be radiated to a greater extent than
from the ordinary fires.
The balls or other blocks used for this purpose will be arranged in a
stratum or layer of suitable thickness, according to the size of the
furnace, a short distance above the grate or other fire-bed, and will be
supported on a secondary grate, or by any other practical means, the
grate being made if necessary of hollow grate bars of metal or any other
suitable substance, and having a water circulation through them to
protect them from the heat to which they will be subject.
By preference round balls will be used, because they will afford
interstices of the best form and of the most regular character for the.
passage of the hot air and the products of the fuel below, and it will
probably be best to have the lower balls or blocks largest, and those
above gradually lessening in size to the top, by which it is believed the

page_text: entire substance carried up by the draft will be more effectually divided
and brought into contact with the hot surfaces.
I do not however limit myself to any particular form or substance for
the balls, nor size nor arrangement of them, and I propose to apply them
to all furnaces, stoves, and ranges of whatever kind or form or use they
may be. Care will be taken to have the area of the mass of balls or
blocks and the capacity of the interstices sufficient to not obstruct the
draft, and if necessary means will be employed to stir about or rearrange
the balls or blocks quickly in case of need for cleaning out the deposit
that may collect in the interstices.
In the same proportion that the balls improve the combustion they
take up the greater heat produced thereby, and prevent most of it from
escaping by the flues in the common furnace, and hold it so that
it is utilized by radiation, and thus not only prevent smoke but at
5 the same time increase the efficiency of the furnace for heating
purposes.
In the application of this method to furnaces already in use, not
having so much room above the fire-grate as would be needed to afford
space below for putting in the fuel, the grate holding the balls will be
0 arranged to rise and fall in order to lift it up temporarily to allow of
feeding the fire; and in the case of a grate having a water circulation
for its protection its connections with the water jacket will be by packed
telescopic pipe joints or any equivalent thereof that will enable it to rise
and fall, and at the same time maintain the proper connection for the
5 circulation of the water.
In cases in which it may be preferred to have the lower or fire-grate
to lower away from the ball-grate for the same object for which the
upper one is here. made to rise I propose to avail myself, of that
alternative, making the upper one stationary, and the lower one
0 movable.
To illustrate the application of the first part of the Invention I have
by way of example represented by the accompanying Drawing, to which
reference is made, a sectional elevation, Figure 1, and a horizontal section,
Figure 2, of the furnace of a boiler of the locomotive type, in which one
5 mode of the application of the adjustable water grate is illustrated, and
in Figure 3, a sectional elevation of a portion of a steam boiler with the
improvements, and Figure 4, a horizontal section, but as before stated

page_text: °
F
the Invention is applicable to any furnace and for any kind of fuel.
Similar letters of reference indicate corresponding parts.
In Figures 1 and 2, A represents the ordinary fire-grate, whereon
the fuel to be burned is placed; B, the grate above for supporting the
balls; and C, the balls, of which in this case I have represented three
tiers superposed, but more or less may be used. Generally they will be
made of metal, having great power to retain heat, and not fusible at
such heat as will be produced by this mode of combustion.
Cast or
wrought iron, Bessemer steel or scrap iron will probably be used. If
the fire-space is low the grate B will be made vertically adjustable as
above stated to enable it to be lifted temporarily for supplying fuel to
the grate below, and when made of ordinary grate-bars it will be raised
and lowered by any simple means, but when made of tubes for a water
circulation the means suitable for raising the ordinary grate will not do,
and the necessary connecting joints for the water circulation will have
to be provided. For these purposes I have in this case represented the
grate as suspended by four tubes F extending up through stuffing
boxes G in the crown sheet H, and connected above it by cross bars I or
any kind of frame, which is suspended from a shaft J by chains K, the
shaft extending out through the front of the furnace, and having a
crank or hand wheel K³ for turning it to raise and lower the grate by
winding the chains on and off. The suspending tubes F are open to the
water space at the upper ends; also to the water space in the tubes of
the grate, and afford means for the circulation of the water as well as
for the support; and also the adjustment of the grates by extending
downward and into the water jacket at the stuffing boxes X or in any
: equivalent way.
In case it may be needful to have greater leverage for raising the
grate and balls, which in some cases will be very heavy, the chains may
wind on a countershaft in the water space, with which the crank shaft
may gear by suitable reducing gears.
In order to prevent the balls from bearing against the walls of the
fire-jacket confining hoops or bands L of Bessemer steel or other metal
or substance protected if necessary with asbestos may be used, as shown
in the Drawing, or any other equivalent means may be employed to hold
the balls away from the walls.
If the draft is obstructed by the balls the flue may be lengthened, or
jets of steam or air may be blown into the fire or the flue anywhere.

page_text: This plan of consuming smoke will be particularly applicable to under-
ground railroads and other works.
The following is a description of another mode of arranging the
adjustable water grate :-
In Figures 3 and 4, A' is the fire-space; B¹, the grate for the fuel;
C', the vertical tube for supporting the balls or scraps; D¹, the grate for
the balls; E¹, the balls; F, the coil connecting with the outer portion
of the grate and confining the balls from the walls of the furnace,
also preventing them from fusing, and also discharging into the main
pipe for promoting the circulation of water in the grate and the
generating of steam; G¹ is the lower stuffing box; H', the upper one;
I, the supporting and adjusting lever; J', a rod connecting them for
raising the grate and lowering it.
Any approved power apparatus may be connected to the lever for
operating and supporting the grate, which in some cases will be very
heavy.
In order that the opening of the pipe C¹ at the upper end will not in
any case rise above the water level, said pipe is slotted at K¹ to make an
opening through the side, and the tube of the stuffing box may be
extended downward as much as necessary to keep it covered. The same.
arrangement may be provided at the bottom if necessary, but with a
well X in the bottom, as here shown for the tube C¹ it will probably be
not required.
If it is desirable not to have a water space below the ash-pit in order
to make more room for the latter, the well may be connected to the
water spaces at the sides by tubes.
To protect the tube C¹ from being burned and roughened-so as not to
work well in the upper stuffing box the packing joint may be arranged
in the water space, and a protecting tube may extend downward from
the crown sheet around the pipe for some distance, and in addition
thereto that portion of the tube working in the packing joint may be
made wholly or in its exterior portion of metal, having greater heat
resisting power than iron. By the circulation of the coil F¹ between
and around the balls they will be largely benefitted by protection from
5 heat, and the generating of the steam will be largely increased. The
vertical tube will also largely aid in the generating of steam. The

page_text: coil F is in this example made to fill a considerable portion of the fire-
space above the balls, which do not need to be very high for the purpose
for which they are used to increase the steam generating capacity, and
it may enter the pipe C¹ for returning the steam to the boiler, but in
this case being made of several seperate coils they are made to connect
directly with the crown sheet by a stuffing joint a, so that they can rise
and fall with the grate. Several short coils are considered better for
keeping full of water than one long coil. The coil F¹ may also be
arranged with a stationary grate and balls for the benefit of rapidly
producing steam, as well as for protecting the balls, and I propose to
employ it in such connection.
Besides the coil I also propose to arrange the short return pipes Y in
the crown sheet; also in the sides of the furnace to extend from the
furnace into the water space, and back again for the more intimate
application of the heat to the water. And in the flues I propose to have
a series of hollow dampers or valves W¹ with water connections through
their axes for a circulation through them to take up as much of the
remaining heat as possible before passing off into the flues, and these
valves or gates will be connected by gear wheels V₁ (shown dotted) so
arranged that by turning one for opening or shutting it the others will
be turned by it in like manner but in reverse direction, so that when
they are partly open they afford a zig-zag course for the heat, which is
thus caused to impinge directly against the side of one gate as it escapes
from the one below, thus obtaining the best possible effect on the water
contained in the valves. This plan is alike applicable to horizontal
flues, and may be extended any required length in either kind.
Besides the direct escape flues in the top of the boiler I also propose
to have one or more return flues A³ extending from the crown sheet
down through the water space, out, at or near the bottom, and up to the
escape pipe with these water dampers W₁ in them for sending the draft
through them to utilize all of the heat thereof in excess of that of the
water in the boiler at the lowest part where it is the coolest.
I also propose to have jet pipes, one or more arranged for discharging
jets of steam against the balls, and the coil of water pipe in connection
therewith for cleaning out the ashes from time to time, and if necessary
to prevent the draft set up by the jets when discharged against the
under side from drawing up the fire or any portion of it I will have

page_text: )
dampers between the fire, and the balls to be closed to relieve the fire of
the suction.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as new and desire to
secure by Letters Patent is,-
1st. The combination of a stratum of balls, blocks, or broken pieces
of metal or other substance with a furnace, stove, range, grate, or other
burner in such manner that the products of combustion rising from
the fire on the grate or other fire-bed will be caused to pass through the
spaces between and around said balls, and be brought into direct contact
with the surface thereof for increasing the combustion and radiation by
the method herein described.
2nd. A vertically adjustable grate having a water circulation in
its bars connected to the water space by an adjustable connection to
enable it to be adjusted and at the same time maintain the circulation
as specified.
3rd. The said grate suspended by the pipes of the said adjustable
connection, substantially as specified.
4th. A windlass J, K, K', or other equivalent raising and lowering
apparatus connected to said grate suspending and adjusting pipes, sub-
stantially as specified.
5th. The suspending pipes F, stuffing boxes G, bars or frame I,
chains K, and shaft J combined and arranged with the grate B, crown
sheet, and water space of the boiler, substantially as specified.
6th. The tubular grate for holding the balls attached to a central
vertically adjustable tube C¹, and connected at the outer part to a
coil F circulating around and between the balls, and returning to
the central tube or directly to the water space, substantially as
specified.
°
•
7th. The combination of a coil F¹ with the balls E' and their sup-
porting grate D', whether the grate be adjustable or not for the
protection of the balls and for generating steam, substantially as
⚫specified.
8th. The coil F¹ extended into the fire-space above the balls for
5 amplifying the generating power of the boiler, substantially as
annoified
ל

page_text: 9th. The return pipes y in the crown sheet and the sides of the
furnace, substantially as specified.
10th. A series of hollow dampers or gates arranged in the flues and
having connections for a water circulation through them to utilize the
escaping heat, substantially as specified.
11th. The said dampers W' geared so as to be turned simultaneously
in opposite directions, substantially as specified.
12th. The return flues A³ from the crown sheet through the water
space to the bottom, with the water dampers W₁ in them, as described,
for economising the escape heat, substantially as specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Sixth day of January,
in the year of our Lord One thousand eight hundred and seventy-
four.
Witness,. .
HENRY W. DEwey,
53, Chancery Lane,
London.
A. M. CLARK. (L.S.) ·