Improvements in and in Connection with Motive rower Engines, Actuated by Pressure due to Heat of Combustion.
Year: 1886

page_text: Date of Application, 3rd Mar., 1886.
Complete Left, 3rd Dec., 1886.
Complete Accepted, 5th Jan., 1887.
Improvements in and in Connection with Motive rower Engines,
Actuated by Pressure due to Heat of Combustion.
I, GEORGE FREDERICK DEACON, of No. 4 Cavendish Road, Birkenhead, in the
County of Chester, Engineer, do hereby declare the nature of my said invention to
be as follows:-
In the present forms of heat engines in which gases or vapours are burned within a
cylinder and actuate a piston, a large proportion of the heat of combustion-in the
best types of such engines probably more than one half—is lost by the mode employed
for keeping the cylinder at a low enough temperature to permit of lubrication.
Water or air are caused to circulate around the cylinder and the temperature of the
cylinder is thus, at a great sacrifice of absolute efficiency prevented from rising too
high. I prevent this loss wholly or partially by introducing between the cylinder and
the heated gases a volume of comparatively cool air or air and gaseous or vapourous
fuel mixed. If the cool volume be air and fuel the mixture must be such that unless
greatly heated it will not explode or burn.
This air, or mixture of fuel and air constitutes a column (between the combustion
chamber at the end of the cylinder most distant from the piston, and the cylinder
itself or between that chamber and both the cylinder and piston) capable of trans-
mitting to the piston the pressure due to combustion of the gases in the combustion
chamber, but incapable in any important degree of transmitting the heat.
When the exhaust port is opened the compressed air, or air and gas, or vapour
expand and drive out a large portion, or the whole of the products of combustion.
If before or when the exhaust port is closed a new charge of cool air, or air and
gaseous or vapourous fuel be introduced from the neighbourhood of the piston the
former column of air, or air and gaseous or vapourous fuel is thereby pushed towards
or into the combustion chamber. Since its entrance the temperature of this column
has been rising and the portions thereof nearest to the combustion chamber, being by
this time very hot, the ignition at that end however caused will take place under the
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page_text: most favourable conditions as to temperature, notwithstanding that owing to the
introduction of a new cool column-the next outward stroke will be made without
any serious heating of the cylinder or piston.
In applying these principles to engines to which the air or air and gaseous or
vapourous fuel is to be compressed within the cylinder before ignition it is impossible
to maintain a column of cool air of the full diameter of the piston, in the manner
hitherto described, because the capacity of the combustion chamber and the space, if
any, intervening between the combustion chamber and the portion of the cylinder
swept through by the piston would be too great to permit the ordinary stroke of the
piston to produce the required compression. I obviate this objection by reducing the
portion of the cross section of the cylinder occupied by the cool column, throughout
a part or the whole of its length, by attaching to the piston a trunk, or displacer pro-
jecting towards the combustion chamber. In the annular space between this trunk or
displacer and the sides of the cylinder the now hollow but cool column of air still
intervenes. This arrangement has moreover two important and distinct advantages
the first being that as the air passes in a thin film between the trunk and the piston
the convection of the heat towards the combustion chamber is more complete. The
second being that radiation from the combustion chamber towards the cylinder and
piston is intercepted by the trunk.
The pressure under which the cool air or air and gaseous or vapourous fuel is intro-
duced may be such that when in the cylinder it falls to the pressure of the atmos-
phere; or it may be introduced at a higher pressure than would be necessary to drive
out the products of combustion, in which case the closing of the exhaust port is so
regulated that the pressure in the cylinder is maintained; or a second and larger
cylinder (on the compound principle) is added in which the residual pressure in the
high pressure cylinder is utilized.

page_text: Actuated by Pressure due to Heat of Combustion.
I, GEORGE FREDERICK DEACON, of No. 4 Cavendish Road, Birkenhead, in the
County of Chester, Engineer, 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 statement :-
In the present forms of heat engines in which gases, or vapours are burned within
a cylinder and actuate a piston, a large proportion of the heat of combustion-in the
best types of such engines probably more than one half-is lost by the mode employed
for keeping the cylinder at a low temperature to permit of lubrication. Water, or air
are caused to circulate around the cylinder and the temperature of the cylinder is
thus, at a great sacrifice of absolute efficiency prevented from rising too high. I
prevent this loss wholly or partially by introducing between the working cylinder and
the heated gases in the combustion chamber a volume of comparatively cool air or air
and gaseous, or vapourous fuel mixed. The vapourous fuel may be that of petroleum,
or other hydrocarbon oil, or spirit which may be introduced either hot, or cold in its
ordinary condition, or mechanically divided, or after volatilization. If the cool
volume be air and fuel the mixture must be such that unless greatly heated it will not
explode, or burn.
This air, or mixture of fuel and air constitutes a column (between the combustion
chamber containing the explosive charge at the end of the cylinder most distant from
the piston and the working cylinder itself, or between that chamber and both the
working cylinder and piston) capable of transmitting to the piston the pressure due to
combustion of the gases in the combustion chamber, but incapable in any important
degree of transmitting the heat.
When the exhaust port is opened the compressed air, or air and gas, or vapour
expand and drive out a large portion, or the whole of the products of combustion.
If before, or when the exhaust port is closed a new charge of cool air, or air and
gaseous, or vapourous fuel be introduced from the neighbourhood of the piston the
former column of air, or air and gaseous, or vapourous fuel is thereby pushed towards,
or into the combustion chamber. Since its entrance the temperature of this column
has been rising and the portions thereof nearest to the combustion chamber being by
this time very liot, the ignition at that end however caused, will take place under the
most favourable conditions as to temperature, notwithstanding that owing to the
introduction of a new cool column-the next outward stroke will be made without
any serious heating of the cylinder, or piston.
In applying these principles to engines to which the air, or air and gaseous, or
vapourous fuel is to be compressed within the cylinder before ignition, it is impossible
to maintain a column of cool air of the full diameter of the piston, in the manner
hitherto described, because the capacity of the combustion chamber and the space, if

page_text: Figure 7 is a section of the piston of the engine.
Figure 8 is a plan of the air and gas valve through which the incombustible mix-
ture is drawn into the cylinder. Figure 9 is a sectional elevation of the eduction
valve and gas admission valve.
The example of engine illustrated in the drawings and hereinafter described is of
the single acting compression type a dilute and incombustible mixture of gas and air
being compressed behind the piston. Towards the inner end of the compressing
stroke the mixture is rendered combustible by the introduction of a separate charge of
gas. The engine is of the return connecting rod design.
In the Drawings A is the cool portion of the cylinder in which works the piston B.
Cis the hot portion of the cylinder in which the combustible mixture is ignited and
burned. To the piston B the trunk B' of slightly less diameter than the cylinder is
attached. The hot and cool portions of the cylinder are made of equal diameters and
the annular space is thus provided, in which is contained the column of cool incom-
bustible gas and air intervening between the hot and cool ends of the cylinder. The
piston trunk B' is constructed as hereinafter described to lessen the conduction of heat
towards the cool piston. The space swept by the front end of the piston B in the
cylinder A serves in this case, as a pump which draws in and slightly compresses into
the reservoir D (formed in the bed of the engine) an incombustible mixture of gas
and air. The pressure of this mixture is such as when the eduction valve E is opened
will sweep out (with, or without the assistance of the first part of the inward stroke
of the piston) a portion, or all of the residual products of combustion. Pressures
from two to five pounds will, according to circumstances, be sufficient to effect this
object. The air and gas is compressed into the reservoir through openings a and an
annular passage a' in the cylinder A. The openings a are so placed in the cylinder
that the piston at the extremity of its outward stroke uncovers them. The eduction
valve having been previously opened the pressure has so far fallen that the confined
gas and air escapes from the reservoir D into the cylinder and sweeps out the required

page_text: quantity of the gaseous products of combustion still remaining in the cylinder. At,
or shortly after the end of the forward stroke the eduction valve is shut and the
incombustible charge of gas and air is compressed by the inward stroke of the piston.
The interior of the inner end of the cylinder will after working for a short time
become very hot. To provide against the heat being conducted to the outer surface
and radiated into the atmosphere, this portion of the cylinder is provided with a lining c
of non-conducting refractory material contained between a thin metal lining and a
thicker metal casing b. The lining is merely for the purpose of protecting the
refractory material from disintegration and the engine from loss by the entrance of
gas into the pores of that material: the resistance to internal pressure tending to
Burst the cylinder being provided by the exterior casing . F is the gas pump
which supplies the gas at or near the inner end of the compression stroke required to
render the charge combustible. is a lift valve admitting gas to the pump and is
the delivery valvo. serves as a second delivery valve and is provided to prevent the
gas (remaining in the pipe between the valve and the pump) from issuing into
the cylinder during the forward stroke. The valves and E are worked by cams g
and & mounted upon a shaft H driven from the main shaft I through the bevel gear J.
The pump F is worked by an eccentric F¹ also mounted on the shaft I. Between the
joints of the hot portion B and the cool portion A of the cylinder there is inserted a
washer of non conducting material such as asbestos board.
Air is admitted to the front end of the cylinder A by the valve d around the seat
of which the gas is also admitted through numerous small holes. The valve is of a
known type and need not therefore be further described. The gas is regulated by a
valve controlled by a governing device of any suitable kind.
The trunk B₁ of the piston Bis made of two portions the outer end e being tapered
and separated from the parallel portion e¹ by a lining of non conducting material
and the interior, or hollow portion is filled with non conducting refractory material.
The ignition may be effected by any suitable known means such as a heated tub,
communication between the interior of the combustion chamber and the heated tube
being made and broken by a valve worked from the shaft H.
The cycle of the engine is as follows:-
Assuming the piston to be at the inner end of its stroke and a charge of and
gas
air of required combustibility to be enclosed in a compressed state (say at 40 lbs.
above the atmosphere) in the combustion chamber, or hot end of the cylinder and
the front end A of the cylinder and reservoir 1 to be charged with an incumbustable
mixture of air and gas the compressed charge in the end is ignited. The expansion
due to combustion drives the piston towards the outer end of its stroke at the same
time compressing the incombustible charge in front of the piston and in the reservoir 1)
wholly into that reservoir. During the same period gas is drawn into the pump F.
The piston nearly arrived at the outer end of its stroke the eduction valve E is opened.
This allows a certain portion of the products of combustion to escape through the
eduction pipe and thus reduces the pressure in the cylinder nearly or quite to that of
the atmosphere. The piston during this escape of the gases uncovers the ports a and
thus forms a communication between the hot portion of the cylinder and the reser-
voir D. As soon as the pressure in the cylinder has fallen below that of the reservoir D,
the cool gas and air from the reservoir will flow towards the hot end C of the
cylinder through the annular space now existing between the wall of the working
cylinder A and the trunk B¹ of the piston B. This action of the air and gas has
the combined effect of sweeping out a greater, or less portion (depending upon the
time of closing the eduction valve) of the products of combustion within the cylinder
and of cooling the wall of the working cylinder A and the piston trunk B₁ besides
causing a removal of the partially heated columu of air and gas previously existing in
this annular space and replacing it with cooler air and gas, thus producing the con-
vection of heat from the working portion of the cylinder towards the hot end.
Moreover in the next outward stroke of the engine the new cool column serves to
prevent the transmission of heat to the cool cylinder and piston.

page_text: By the example above described it will be seen that by introducing a column of air,
air and gas or vapour round the trunk of a piston such as B' as described, the heat
due to combustion within the cylinder is rendered incapable of being transmitted to
the working piston and cylinder of the engine to any deleterious extent, and that a
certain quantity of the heat communicated to the piston and the working barrel of the
cylinder is taken up by the next incoming air, or gas and air and instead of being lost
is conveyed towards the hot end where it is utilized and to some extent augments
the absolute efficiency of the engine.
The method of working herein described namely the introduction into the cylinder
of the incombustible charge above referred to and the subsequent introduction of a
charge of gas to obtain combustibility may be employed in various types of gas, or
vapour and air engines. The final charge of gas may be introduced into the incom-
hustible mixture already within the cylinder at, or about the point and moment at
which it is desired to ignite the charge, or earlier. Or, it may be introduced to obtain
a prolonged burning action within the cylinder in which case it is introduced as
a prolonged injection by the pump.
I would have it understood that the method of working herein described, namely
with an incombustible charge of air and gas or vapour introduced into the cylinder, or
combustion chamber, in, or in connection with the cylinder of an engine worked the
pressure due to the heat of combustion and with a subsequent introduction of fuel to
render the total mixture combustible may be employed in, or in connection with
various types of engines. When this method is employed in an engine of the hot-
ended type (such as herein described) a sufficiently intimate mixture is secured without
the inconveniences attending the use of a combustible charge within, or in close
connection with a hot eylinder, or combustion chamber before ignition.
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 :
First. In motive power engines actuated by pressure upon a piston due to the heat
of combustion of gas, or vapour within a cylinder, or combustion chamber the intro-
duction between the charge and the piston of a column of incombustible air, or air
and gas, or vapour, for the purpose of insulating the piston and working barrel of the
cylinder from the heat of combustion, substantially as set forth.
Second. In motive power engines actuated by pressure due to the heat of combus-
tion of gas and vapour within a cylinder, or combustion chamber the introduction of
the air or part thereof or of a mixture of incombustible air and gas or vapour, to the
cylinder through an annular space between the side of the cylinder and a trunk
whereby so much of the heat of combustion which has reached the working cylinder
and piston is carried back to the combustion chamber as is necessary in order to
maintain the working barrel of the cylinder at a moderate temperature and whereby
the volume of the column of air or air and gas or vapour is diminished.
Third. In motive power engines actuated by pressure due to the heat of combustion
within a cylinder, or combustion chamber the cycle of operations, by which after
ignition of the charge at the inner end of the cylinder the piston is pressed forward
and compresses a charge of air or air and gas, or vapour, which at, or near the begin-
ning of the inward stroke, expands into the cylinder, driving the products of combus-
tion from the forward end through the eduction port, situated at, or near the inner end
of the cylinder, or combustion chamber, and is itself again compressed in the inner
end of the cylinder during the inward stroke and with or without a further charge of
gas, or vapour is ignited at, or near the beginning of the next forward stroke.
Fourth. In motive power engines actuated by pressure due to the heat of combus-
tion within a cylinder, or combustion chamber the use of an incombustible charge of
air and gas, or vapour, to which is added, before ignition a further charge of such fuel
to render the total mixture combustible.
Fifth. In motive power engines actuated by pressure due to the heat of combustion
within a cylinder or combustion chamber the construction of the combustion chamber

page_text: substantially as and for the purposes set forth consisting essentially of a thin lining
(such as b) and a strong casing (such as b') and a layer of refractory material (c)
between such lining and casing.
Sixth. The piston trunk constructed substantially as set forth with reference to
Figure 7 of the Drawings.
Seventh. The construction and arrangement of engine as set forth with reference
to the Drawings hereto annexed.