A NEW AND USEFUL APPARATUS FOR GENERATING MOTIVE POWER FROM HEATED AIR, STEAM, AND THE PRODUCTS OF THE COMBUSTION OF COAL OR OTHER FUEL
Year: 1855

page_text: LETTERS PATENT to Francis Brown Blanchard, of the State of Maine, of
the United States of America, for the Invention of "A NEW AND USEFUL
APPARATUS FOR GENERATING MOTIVE POWER FROM HEATED AIR, STEAM, AND
THE PRODUCTS OF THE COMBUSTION OF COAL OR OTHER FUEL."
Sealed the 24th April 1855, and dated the 14th February 1855.
PROVISIONAL SPECIFICATION left by the said Francis Brown Blanchard
at the Office of the Commissioners of Patents, with his Petition, on
the 14th February 1855.
I, FRANCIS BROWN BLANCHARD, of the State of Maine, of the United States
of America, do hereby declare the nature of the Invention for "A NEW
AND USEFUL APPARATUS FOR GENERATING MOTIVE POWER FROM HEATED AIR
STEAM, AND THE PRODUCTS OF THE COMBUSTION OF COAL OR OTHER FUEL," to be
as follows:-
My Invention consists in combining a furnace, a boiler, and pipes or means
of connection, and an eduction pipe for the supply of the gases and vapour or
steam to an engine cylinder, in such manner that the mixture of the steam and
gases may be caused to take place in the furnace or chamber, or steam space,
or stack of pipes leading therefrom, instead of passing the gases into the water,.
and through it into the steam space of the boiler, by which I am enabled to

page_text: employ the gases with such an admixture of steam or vapouras circumstances
inay require.
It further consists in combining with a boiler and stack of tubes, two
chambers and their connection pipes, such chambers, pipes, and stack of tubes
being used for the purpose of regulating the temperature of the mixture of
steam and gases.
It further consists in a tubular feed-water apparatus or vessel, and a
tubular air essel, so combined together and with the boiler and its furnace,
that the exhaust of the engine may be made to pass through them, and impart
heat to the water and air in the process of being supplied to the boiler
or furnace.
It further consists in combining with the air pump and the furnace, the
tubular air condenser, constructed for the purpose of reducing the heat of
the condensed air, and relieving the air pump from back pressure.
It further consists in combining with a closed furnace flues or heating
surfaces, to reduce the temperature of the product of combustion to a degree
that it may be used through an engine, either with or without a union of the
steam and gases, before they enter the engine or engines.
It further consists in arranging the furnace so made that it shall withstand
the pressure, and enable a person to see through, for the purpose of regulating
the pressure.
It further consists in combining with the coal feeder a distributing valve,
and in arranging hollow grates on an angle, so as to distribute the coal.
It also consists in combining the hollow grates with the closed furnace and
heating surfaces, to prevent them from fusing when the heat is retained
under pressure.
It further cousists in so applying the rakes, by means of moveable stuffing
boxes, as to retain the pressure in the furnace while they are performing their
office, and to enable them to be moved as occasion may require.
It further consists in the employment of a wire gauze partition, in order to
prevent any ashes from passing into the pipe to the engine.
It further consists in introducing steam into the closed furnace, in order that
after it has aided in carrying on combustion, the product may be used with the
other products through the engine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Francis Brown Blanchard in the Great Seal Patent Office on
the 3rd May 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANCIS
BROWN BLANCHARD, of Waterville, of the State of Maine, of the United States
of America, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of February, A.D. 1855, in the
eighteenth year of Her reign, did for Herself, Her heirs and successors, give
and grant unto me, the said Francis Brown Blanchard, Her special license
that I, the said Francis Brown Blanchard, my executors, administrators, and
assigns, or such others as I, the said Francis Brown Blanchard, my executors,
administrators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Mau, an Invention of "A NEW AND USEFUL APPARATUS FOR GENERATING MOTIVE
POWER FROM HEATED AIR. STEAM, AND THE PRODUCTS OF THE COMBUSTION OF COAL
OR OTHER FUEL," upon the condition [amongst others] that I, the said Francis
Brown Blanchard, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office, or Office of Her Majesty's Commis.
sioners of Patents, within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Francis Brown Blanchard, do hereby
declare the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following Specification, and the accompanying Drawings, letters, figures, and
references thereof.
Of the said Drawings, Figure 1 (Sheet 1) is an isometrical view of my
Invention; Figure 2 (Sheet 1) is a longitudinal and central section of an
air condenser, to be herein-after described.
Figure 1 (Sheet 2) is a top view of the boiler of my Invention; Figure 2
(Sheet 2) is a vertical, central, and longitudinal section of the said Iuvention,
said section being taken through the line 1, 2, of Sheet 2; Figure 3 (Sheet 2) is
a vertical and transverse section of the Invention, it being taken on the liue 3,4,

page_text: of Figure 1; Figure 4 is a transverse and vertical section of the Invention,
taken through the line 5, 6, of Figure 1; Figure 5 is a similar section, taken
on the line 7, 8, of Figure 1. By this apparatus it is intended that the
smoke arising from combustion shall be consuined within a closed furnace,
and, in connection with compressed air, introduced into the furnace.
The same may be said with regard to the volatile products of combustion
that are susceptible of being consumed by heat; the volatile products that
are not combustible being made to pass through the flues, and to yield a
portion of their heat to the water of the boiler, so as to aid in the formation of
steam, while they subsequently united with steam, and used in connection
therewith, as an effective force or motor for operating the piston of a steam
engine cylinder.
The exhaust from the engine is to be caused to pass through a tubular feed-
water vessel (in communication with the boiler), and from thence through an
air vessel of similar construction, made to communicate with the furnace. The
exhaust enters the top of each vessel, and passes off at the bottom of each; the
coldestportion being the heavierpassesoff, while the lighter and hotterremains
in the vessel until it has expended its heat, when it will pass downward, and
give place to other portions that may be flowing into the vessel. Steam, if
formed in the water vessel, will pass into the boiler. In this manner a portion
of the heat, which would otherwise be lost in the exhaust, is carried back into
the furnace, and again made to do duty.
Having thus premised, I will now proceed to explain the particular features
of my Invention, wishing it to be understood that the same letters of reference
are intended to exhibit like parts in the several Figures.
A is a boiler, made in form somewhat like that used in ordinary locomotive
steam engines, and provided with a fire box B. C, C¹, are cylindrical or
other proper shaped chambers for collection of the volatile products of com-
bustion. The first of these chambers is separated from the fire box or
furnace by a brick partition D, having openings a, a, for the volatile pro-
ducts of combustion to pass from the fire box into the chamber C; said
two chambers C, C³, are connected by a stack of hollow tubes or pipes b, b.
E is a pipe through which fuel is supplied to the fire box, such pipe being
supplied with two valves, viz., a slide valve a, and a hinged valve d. e is a
pipe for relieving the valve of the pressure during the operation of charging
or supplying the fire box with fuel. This pipe has two cocks 1 and 2, and is
made to connect or open into the spaces directly above and below the valve
d, as seen in Figure 3 (Sheet 2). The valve c is opened or closed by means
of a screw x. The fuel is put into the pipe P through a funnel z at its

page_text: top, and rests on the valve d, the valve c being supposed to be open; this
being effected, the valve is to be closed, and the cock 2 in pipe e to be
open. This operation will equalize the pressure on the opposite side of the
valve d, and permit said valve to be let downward by means of its handle y,
so as to discharge into the furnace the fuel that may be resting upon it.
Next, the valve d and cock are to be closed, and the cock 1 is to be
opened, thereby not only causing pressure to be exerted on the valve d,
but relieving the valve c, so that it may be open preparatory to another
charge of fuel being thrown into the mouth e. F is a rectangular or
other proper shaped chest or chamber, situated at the lower end of and
making part of the pipe E, and made to open into the fire box B. T'his
chest is provided with a fuel distributor f, which is a turning plate or valve,
operated or turned by means of a screw g. By setting this distributor at any
desirable angle, the fuel that drops through the pipe may be reflected or dis-
tributed in a longitudinal direction to any desirable part of the furnace. The
transverse distribution of the fuel may be effected by means of a hollow ridge
or vessel G [formed triangular in cross section], assisted by the inclination of
the grate bars h, h, which are arranged in the furnace, as seen in the Drawings.
The grate bars are to be formed of wrought metal pipes, and made to com-
municate with the water space H, H, surrounding the fire box, the water of
the boiler being suffered to flow freely through the pipes. The water is also
made to freely circulate through the ridge or hollow vessel G by means of
pipes i, i, one passing out of its top and the other out of its bottom, and being
made to open into the water space of the boiler. Air is to be supplied to the
furnace by means of one or more air pumps, by which it is to be made to flow
into the reservoir 1 (Figure 1, Sheet 1), and from thence, by means of pipes
J, J, and j,j, into the furnace, it being carried above and below the fire grate,
as seen in Figure 3, Sheet 2. k, Figure 1 (Sheet 1), is a pipe, made to com-
municate with the steam space in the boiler and that part of the fire box
which is under thegrates, such pipe being for the purpose of conveying steam to
the furnace. The line K denotes the water line of the boiler; l, l, are pokers
or rakes, operating through air-tight universal joints m, m³. These pokers are
used for the purpose of clearing the grates from ashes, and raking the same
into the valve chamber L, said pokers or rakes being constructed in any
suitable manner to enable such to be easily accomplished. The said chamber L
is provided with a slide valve n, through the openings of which the refuso
of the grates may be removed from the fire box, as occasion may require.
The furnace is provided with sight tubes o, o, which are formed tapering, and
respectively provided with discs of plate glass, or other suitable transparent

page_text: material, held in place by nuts p, p, and proper packing. 2, 2, are cocks for
the discharge of ashes from the chambers C, C', such cocks being applied to
said chambers or tubes leading out of the same, as seen in Figure 2(Sheet 2).
Thechamber C' is provided with a net work partition or perforated diaphragm,
the object of which is to prevent the passage of ashes or cinders into the pipe
N, leading out of said chamber. M, M, are pipes passing from the steam space
of the boiler into the chambers C, C, such pipes being provided with valves
on their upper ends, as seen in Figure (Sheet 2); these valves are operated
or raised and depressed by screws 1, . By means of these pipes, steam from
the boiler can be admitted to the chambers C, C', in order that it may be
mixed with the gases, air, or volatile products of combustion. that may be
therein. S is a tube that extends downwards through the boiler into the
chamber C. This tube is closed at its lower end and open at its upper end,
in order that a thermometer may be suspended in it, for the purpose of ascer
taining the temperature. of the steam, air, and guses previous to the passage of
the same into the engine. N, Figure 2 (Sheet 2), is the eduction pipe, that leads
from the chamber C¹ to the engine or the valve chest of the cylinder thereof.
This pipe has a branch pipe O, which contains a slide valve t, that inay be
opened when the valve of the engine pipe is closed, such engine pipe being
supposed to be provided with a closing valve. The valve n beneath the
furnace is likewise opened at the same time, this latter valve allowing a free
admission of air into the furnace, while the former permits the escape of
the gases during the process of setting the fuel on fire, or during any
temporary suspension of the action of the air pump.
feed water is seen at P; it is constructed like the air heater I, that is to say,
it is the cylindrical vessel divided into three chainbers by two horizontal
partitions, between which a stack of pipes extends, and opens free communi-
cation between the two external chambers. The said heater P is placed
between the boiler and feed pump. The exhaust of the hot air, gases, and
steam from the engine should be made to pass into the heater by means of a
pipe u, which opens into the middle chamber thereof; the exhaust thus
surrounds the tubes of the heater, or is in contact with their external surfaces,
while the feed water occupies the two external chambers and -the internal
parts of the tube. From the internal chamber the exhaust, or air, gases, and
steam pass off by the pipe into the air receiver I, and surrounds the tubes
externally, as in the water heater. The cold air is made to pass from the ai
pump through the pipe wand into the air receiver I, and through its tubes,
and from thence into the furnace by the pipes J, J, becoming heated during
its progress through the tubes by the caloric imparted to them by the exhaust
The heater for the

page_text: which is allowed to flow from the air heater into the atmosphere or into pipes
to heat buildings. Upon the boiler I have placed a safety valve R. Between
the air pumps and the air receiver I, I sometimes make use of what I term
an air condenser, which is represented in vertical and longitudinal section in
Figure 2 (Sheet 1); it is a cylindrical vessel, divided by cross partitions into
several compartments b, b,b, which are connected by openings in the partitions,
respectively provided with valves a, . Each of the compartments b, b, b, has
a stack of tubes extending through it, which are supported in partitions
extending transversely across the interior of the air condenser, the same being
as seen in the Drawings. Each end of the condenser is provided with a pipe,
as seen at A and B, the air from the air pumps being made to pass into the
vessel by the pipe A, and by the pipe B to proceed from it into the air
receiver I. The external surfaces of the tubes of each of the stacks of the
condenser are to be kept in contact with cold water, in order that when air is
passed through the condenser, the temperature of it may be reduced, and the
resistance on the air pumps proportionably decreased. The two pipes M, M,
leading from the steam space into the chambers C, C', are not only to admit
steam into the chambers C, C1, so as to commingle with the gases of the
furnace, but they are for the purpose of regulating the temperature of the
mixture before it is made to enter the engine.
Provided the steam be admitted into the chamber nearest the furnace, it
will take up a portion of the heat therein, thus reducing the heat of the gases
thereof, and increasing the rapidity of the current passing through the stack
of pipes into the chamber C¹. Such an increase in the velocity of the current
will of course cause it to yield up less of its heat to the tubes than would
result were it to remain longer in contact with them. In case we admit
steam into the chamber C¹, the volume to pass through the tubular stack will
be diminished, consequently its motion will be slower; and after it has
expended most of its heat in the tubular section or stack, it will come in
contact with the steam, to which it will yield a portion of its heat until the
temperature of the mixture is equalized. The tubes can be constructed with
such length and surface as may be found to enable them to operate to the
best advantage. The tubular air receiver, shown in Figure 2 (Sheet 1), was
described as divided into compartments, with a valve to each of them. The
design of this is, that the air which may be lodged in each section, at each
stroke of the air pump, shall be held from going back out of the same. As
the pipes of such sections or compartments are brought in contact with water
colder than that of the atmosphere in the condenser, the air from the air
pumps will not have the same resistance in the whole stroke, as the valves will

page_text: successively open, according as heat has been thrown off in the sections during
the time the air pump is making its return stroke.
In operating with my apparatus, the furnace is to be charged with coal or
fuel, which being ignited, bellows may be used to promote combustion; or the
valve under the ash-pit may be opened, so as to admit air to the fire until
the fuel is thoroughly kindled. Under these circumstances, the valve or cock
of the pipe communicating with the engine should be closed, and the valve t of
the branch communicating with the chimney opened, and kept so until the
combustion is active enough to consume the combustible gases. This done,
the chimney valve should be closed, the engine valve opened, and the engine
put in motion.
The valve n should be closed, and the air to the furnace be
supplied by the air pumps.
When the steam is up, it should be allowed to flow from the steam space
into either of the chambers C, C¹. If more expansive force and less evapora-
tion is wanted, the steam and a portion of air should be admitted to that
chamber which is nearest to the furnace. If more evaporation and less
expansion be desired, the steam should be admitted into the other chamber,
allowing the heat of the gases in the chamber C to expend itself in the water.
The said two chambers and theirpipes M, M, thus operate as a regulator of the
temperature of the mixture of steam, air, and gases to be introduced into the
engine, steam being admitted to the gases through either or both of the pipes,
and in such quantities as occasion may require. The pipes of the stacks should
be long enough, or there should be a sufficient quantity of them, to reduce the
temperature of the gases low enough to enable them to be passed through
the engine with the steam without injuriously effecting the lubricating matter
applied to the piston. A regard for the preservation of the oil or lubricating
matter of the piston should be especially had in this apparatus, and hence the
employment of the tube S for ascertaining the temperature of the mixture
of gases, air, and steam. The air from the air vessel, or a due proportion of
such air, may be employed to reduce the temperature of the gases, using the
expansive force of the air and tempering down the heat to a using point,
making the apparatus almost entirely an air engine, the water surfaces of
the boiler serving to prevent the heat from injuring it, while what steam may
be formed is used expansively.
In Figure 3 (Sheet 1), I have exhibited a top view of the boiler and its
furnace, the air and water vessels I and P, the air condenser and the air
pump, they being therein represented in their positions with respect to each
other. I would remark, however, that when the air condenser is dispensed
with, the air from the air pump is to be led directly into the vessel I, through

page_text: the pipe w (see Figure 1, Sheet1), such pipe w and such Figure corresponding
with the pipes B of Figures 2 and 3.
I am aware that an air-condensing apparatus, a closed furnace, a boiler, and
a cap valve connection of the boiler and furnace, have been so combined that
the gaseous and volatile products of combustion of the furnace have been
made to pass directly from the valve opening into the water and steam of
the boiler, and afterward led from the boiler to a steam engine cylinder, so
that the combination of the gases and vapors could be used as a motive power.
I therefore do not claim such; but what I do claim is, so combining the
furnace boiler, the pipes or means of connection of the two, and the eduction
pipe for the supply of the gases, air, and vapor or steam to the engine cylinder,
that the mixture of the steam, air, and gases may be caused to take place
within the furnace, or smoke chainber or chambers, or stack of pipes leading
therefrom, instead of within the boiler, my improvement enabling me to
employ the gases with such an admixture of steam and air, as circumstances
may require.
I also claim, in combination with the boiler and stack of tubes b, b, b, or
their equivalent, the two chambers C, C', and their respective connection
pipes M, M, such chambers, pipes, and stack of tubes being used for the
purpose of regulating the temperature of the mixture of steam and gases, or
producing results, substantially as specified.
I also claim a tubular feed-water apparatus or vessel and a tubular air
vessel, so combined together and with the boiler and its furnace, that the
exhaust of the engine may be made to pass through them, and impart heat
to the water and air in the process of being supplied to the boiler or furnace,
as described.
I also claim, in combination with the air pump and the furnace, the tubular
air condenser, constructed substantially as described, and for the purpose of
reducing the heat of the condensed air, and relieving the air pump from back
pressure, substantially as set forth.
In combination with a closed furnace, 1 claim the use of the flues or heating
surfaces, to reduce and regulate the temperature of the product of combustion
to a degree that it may be used through an engine, either with or without a
union of the steam, air, and gases before they enter the engine or engines, as
may in practice be preferred.
I claim combining with the furnace a device, so made that it shall withstand
the pressure, and enable a person to see through it (the said device), for the
purpose of regulating the furnace, as specified.
I claim combining with the coal feeder the distribution valve f. I do not

page_text: claim hollow grates, but I claim arranging them on an angle as described, so
as to distribute the coal; and I also claim the hollow grates in combination
with the closed furnace and heating surfaces, to prevent them from fusing when
the heat is retained under pressure sufficiently long enough to reduce the
products of combustion to a fit state for use, as specified.
I claim to so apply the rakes, by means of moveable stuffing boxes, as
described, as to retain the pressure in the furnace while they are performing
their office and to enabled them to be moved as occasion may require.
I also claim the employment of the wire gauze partition as stated, in order
to prevent any ashes from passing into the pipe to the engine.
And I claim the introduction of steam into the closed furnace, in order that
after it has aided in carrying on combustion, the product may be used with the
other products through the engine, not meaning to claim the introduction of
steam for the purpose of only facilitating combustion, as such is not new.
In testimony whereof, I have hereunto set my signature and seal, this
Sixth day of April, in the year of our Lord One thousand eight hundred
and fifty-five
FRANCIS BROWN BLANCHARD. (L.S.)
FRANCIS BROWN BLANCHARD. (L.S.)