Improvements in Fluid Pressure Heat Engines.
Year: 1895

page_text: Date of Application, 8th Mar., 1895
Complete Specification Left, 9th Dec., 1895-Accepted, 1st Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in Fluid Pressure Heat Engines.
I, ADOLF KOLBE of 67 Zeil, Frankfort-on-the-Main in the Empire of Germany,
Merchant, do hereby declare the nature of this invention to be as follows:-
In machines driven by heat, such as for instance gas engines, which convert the
energy of the gases of combustion direct into energy of, movement, a crank
mechanism with a fly-wheel has hitherto been employed for conveying the momentum
of the revolving parts to the piston and vice versa. The steam engine has in fact
remained the type for such heat operated machines notwithstanding the fact that
the action is an essentially different one. Whilst in steam engines the energy
of
the steam alone loads the crank gearing, in these explosion or combustion engines
three degrees of action are present:-The compression of the charge, the expansion
without supply of heat, and the difference between this expansion and the
expansion when heat is applied, that is the useful power.
The first two actions
are, in an ideal machine, equal to one another but with different indications in
variable periods of time, and they may be described as "inner work."
"
"
In heat driven engines which, theoretically work with a strong compression for
increasing the thermic useful effect, the "inner work may be very much greater
than the useful work, and a considerable loading of the crank gearing through the
"inner work will thus take place. This separation of the different degrees of
energy and comparison of the "inner work" with the useful work, which is
in the present Specification explained clearly for the first time, leads to the
consideration whether it would not be possible to prevent this "inner work
from being transferred to the crank gearing. A solution of this is afforded by the
present invention.
"
To facilitate explanation take the case of an ordinary closed cylinder with the
usual compressing chambers, piston, flywheel, and crank gearing, and assume the
distributing valves and other mechanical parts also the igniting mechanism and
the mechanism for supplying heat to be omitted, and only the process of the
"inner work" to be considered. The mass of the piston and of the coupling-rod
is to be assumed to be nil., and an equal volume of gas to be in both halves of the
cylinder with the piston in a middle position, so that the latter will be in stable
equilibrium; also that the mass of the flywheel is large enough, as has hitherto
been customary, to absorb the energy developed by the expansion and compression,
and of sufficient dimensions to equalise the movement; also that losses by friction,
radiation and adiabatic compression do not take place; in other words assume it to
be an ideal machine of the usual form of construction.
If by the rotation of the flywheel by the application of outside energy the
piston is so moved that it compresses the motive fluid in one end of the cylinder
then, as is well known, a portion of the energy applied will be stored up as
potential energy in the compression and heating of the gases in the said part of
the cylinder similarly to the compression of a spring.
If the crank pass the dead point, the gas again expands, and the potential
energy is reconverted into kinetic energy in the mass of the flywheel, by means of
the crank gearing; in the middle position of the piston the potential energy
becomes a minimum and the kinetic energy a maximum. If the piston be then
further moved towards the other end of the cylinder, compression takes place
there and kinetic energy is converted into potential energy and so forth.

page_text: If now the requirement of a constant speed for the flywheel be abandoned and
the fly-rim be constructed in such a way that, in the middle position of the piston
at the maximum of the kinetic energy, it contains exactly enough mass to fully
absorb at a given speed the said energy from the expansion action, the kinetic
energy of the flywheel, or fly-rim will at the end of the stroke be nil.; the
potential energy of the expanded gases will on the other hand be a maximum.
Reversal of movement of the fly-rim may also take place and the flywheel run
back until the next change of stroke and the action be repeated as before at each
to and fro movement of the piston. In both arrangements that is the first the
ordinary one with a revolving flywheel and the second with oscillating fly-rim, a
change of energy takes place and a transference of energy of the "inner work,"
the part producing this being here always the crank mechanism.
If the crank be made to coincide with the centre of the fly-rim, the mass of
the fly-rim will move with the mass of the connecting rod in a straight line instead
of in an arc of a circle; this connecting rod mass may therefore be inserted
either in the piston as a piston mass, or separately in a specially attached body.
The solution is thereby also afforded of relieving the crank gearing from the
"inner work" the conversion of energy for the compressions and equivalent
expansions taking place during one movement of the piston without the supply of
heat, merely in the direction of the axis of pressure of the piston, without a lever
and without a crank gearing.
The actual effective work may be delivered to the outside as hitherto by means
of crank gearing or other suitable means.
This is the essential part of the new arrangement for the above mentioned heat
driven engines.
The hereinbefore described to a certain extent ideal form of new engines with
separate conversion of energy for the "inner work" may be arranged in various
ways to meet the requirements of practical construction.
For instance where the so-called four stroke cycle is used, two cylinders closed
at both ends or four cylinders closed each at one end only with suitable pistons are
necessary. The pistons which are suitably inter-connected are either formed of
such a mass for a given speed and a given compressing action as to absorb the
energy of the "inner work as hereinbefore mentioned, or a suitable mass may
be connected to the piston rod.
"
If then the motive fluid, for instance the mixture of gas and air be drawn into
the cylinder (in the first arrangement of two cylinders) to the left of one piston,
be there compressed, be expelled from the left of the other piston, be expanded to
the right of the first piston and drawn into the right of the second piston or with
the other arrangement of distributing gear (in the second arrangement of four
cylinders closed each at one end) if the mixture be compressed to the left of the
first piston drawn in to the right of the second piston, expelled from the left of
the third piston and expanded to the right of the fourth piston, it is evident that
according to the action hereinbefore described, at least two cylinders closed at
both ends or four cylinders closed each at one end must be employed for the four
stroke cycle. Alterations in the load, irregularities in the distribution, in the
ignition or in the valve washers, which all produce a certain inequality of stroke
in this arrangement with oscillating masses and a destruction of the machinery in
the case of the inelastic connection of the piston and the oscillating masses with
the crank gearing, must be provided for by an elastic connection of the piston and
oscillating masses with the driving mechanism, for instance by the insertion of a
spring.
This necessity for elastic connection with the driving mechanism which conveys
the useful work, may also be effected by causing the compressed gases themselves,
and not the piston rod, to act as motive power in a special machine. In this
case, apart from the ordinary distributing devices hitherto employed, the cylinders
are suitably connected with a distributing slide, so that, for instance (in the first
arrangement with two cylinders closed at both ends)'gas and air are compressed to

page_text: the left of one piston, drawn in to the right thereof, consumed and expanded to
the right of the other piston and from the left of this latter the gases of combustion
are forced to a compressed air receiver and to a machine which works like an
ordinary compressed-air driven engine. The cooling may take place in front of
the receiver and a preliminary heating behind the receiver and before, or in the
compressed air engine with the object of diminishing the work of compression and
increasing the expansion action. The distribution may also be so arranged that
always those cylinders in which combustion takes place are connected with the
compressed air engine or a part of the mixture compressed in excess may be
allowed to expand towards the said engine without ignition, from those cylinders
in which compression takes place. On the next stroke this portion of the
mixture may be drawn back towards the cylinders and then after a second
compression be exploded therein. If the mixture be formed only after the
compression, the air or the gas may he allowed to operate separately in the
compressed air engine.
By alterations in the distribution, the number of the cylinders, and the form
and arrangement of the compressed air engine, a number of various forms of
construction may be for that matter evolved. It is evident that the conversion
with compressed air may also be carried ont with special compressors. Instead of
air, any other suitable gas or liquid may be employed as pressure medium. If the
oscillating pistons be connected with an oscillating electric current producer, for
instance an armature with inducing coils in the field of a magnet and the armature
coils be connected with an alternating current motor (if a constant current be used
with a constant current motor) then by means of this "elastic" electric conversion,
energy of movement may be given off as useful work. By the displacement of
the mass which receives the energy of the inner work" from the flywheel into
the connecting mass, a further step towards simplification may be made. It has
been hereinbefore shown that by compression kinetic energy was converted into
potential energy, which on expansion was reconverted into kinetic, and then finally
again into potential energy of the gas compressed. If the cylinder be now placed
upright, in place of the potential energy of the expanded gas there may be
employed the potential energy of the position of the oscillating body or mass
because gravity now comes into action.
This arrangement may be employed for instance in connection with the four
stroke cycle.
A condensed mixture is contained below one piston, is consumed and expands
below another and upper piston and during this process is drawn in first stroke
the pistons thus more upwards with at first an accelerated and then a decreasing
speed. On the change of direction, the energy for the next compression is stored
up in the coupling mass or body as potential energy. On the descent, compression
always takes place below the upper piston, and expulsion below the lower piston
(preferably forced towards a compressed-air engine) second stroke. On the third
stroke combustion and expansion takes place below the upper piston, drawing in of
the mixture below the lower piston, and so forth. Even here the delivery of
useful work may be made electrically or by compressed air by means of special
compressors, or by compressing in the compressed air engine either combustion
gases, or a portion of the compressed air. In case a compression does not take
place or interruptions in the distribution, ignition, and so forth should take place,
there must be provided in the machine, safety devices which render harmless or
brake to a certain extent the new energy of movement of the pistons unconsumed
by compression. These devices may consist of purely mechanical brakes, liquid
brakes, air buffers, magnetic brakes, or if an electric conversion of energy be
employed, of short circuiting devices for the induced part, so that here, for instance,
the kinetic energy is converted into electricity and heat and utilised before the
piston reaches the bottom of the cylinder.
Such braking devices (for instance the lever of the short circuiting device) are
operated or released on the stroke being exceeded, by means of the usual mechanical

page_text: arrangements, oscillating parts, projections, pins, or by a gas-pressure gauge, which,
on the normal compressing pressure not taking place, acts at the right time on such
braking devices.
The following may in conclusion be mentioned of other possible modifications of
the arrangements hereinbefore described.-
First, the piston may be stationary and the cylinder oscillating, in which case
the mass or body must be connected or united with the cylinder. Further, the
mass may be connected rigidly or by means of springs with the piston, the piston
rod or the like. Instead of one, several cylinders may be arranged parallel or
concentric to one another, or in series, but always with parallel axes of pressure.
For two cylinders each closed at one end and which open towards one another, a
common plunger may be employed. Instead of the crank gearing, racks and
ratchet wheels and other like mechanism may be employed for conveying the
effective work.
It is finally immaterial for the essential part of this invention with what kind
of heating material, such as gas, petroleum, or coal dust the heat machine is
driven and how the regulating and distributing devices are arranged.
Dated this 7th day of March 1895.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Fluid Pressure Heat Engines.
I, ADOLF KOLBE of 67 Zeil, Frankfort-on-the-Main in the Empire of Germany,
Merchant, 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 :-
In machines driven by heat, such as for instance gas engines, which convert
the energy of the gases of combustion direct into energy of movement, a crank
mechanism with a fly-wheel has hitherto been employed for conveying the
momentum of the revolving parts to the piston and vice versa. The steam engine
has in fact remained the type for such heat operated machines notwithstanding the
fact that the action is an essentially different one. Whilst in steam engines the
energy of the steam alone loads the crank gearing, in these explosion or combustion
engines three degrees of action are present:-The compression of the charge, the
expansion without supply of heat, and the difference between this expansion and
the expansion when heat is applied, that is the useful power. The first two actions
are, in an ideal machine, equal to one another but with different indications in
variable periods of time, and they may be described as inner work."
In heat driven engines which, theoretically work with a strong compression for
increasing the thermic useful effect, the "inner work"
may be very much greater
than the useful work, and a considerable loading of the crank gearing through the
"inner work" will thus take place. This separation of the different degrees of
energy and comparison of the "inner work" with the useful work, which is in the
present Specification explained clearly for the first time, leads to the consideration
whether it would not be possible to prevent this "inner work from being
transferred to the crank gearing. A solution of this is afforded by the present
invention.
In the accompanying drawings-
65
Figure 1 is a diagram of the arrangement at present employed;
"
Figure 2 is a diagram showing the use of a separate mass moving in a straight.
line;
Figure 3 shows a diagram of the arrangement employed in a four stroke cycle
with two cylinders closed at both ends;

page_text: Figure 4 the same with four cylinders closed at one end.
Figure 5 is a diagram of another form of arrangement.
Figure 6 is a diagram of a further modification for electric operation.
Figure 7 shows a modification with the cylinders placed upright.
To facilitate explanation take the case of an ordinary closed cylinder Z
(Figure 1) with the usual compressing chambers V₁ V2, piston K, flywheel R, and
crank gearing, and assume the distributing valves and other mechanical parts also
the igniting mechanism and the mechanism for supplying heat to be omitted, and
only the process of the "inner work" to be considered. The mass of the piston
and of the coupling-rod is to be assumed to be nil., and an equal volume of gas to
be in both halves of the cylinder with the piston K, in a middle position, so that
the latter will be in stable equilibrium; also that the mass of the flywheel is
large enough, as has hitherto been customary, to absorb the energy developed by
the expansion and compression, and of sufficient dimensions to equalise the
movement; also that losses by friction, radiation and adiabatic compression do
not take place; in other words assume it to be an ideal machine of the usual form
of construction.
If by the rotation of the flywheel R by the application of outside energy the
piston is so moved that it compresses the motive fluid in one end V2 of the cylinder
then, as is well known, a portion of the energy applied will be stored up as
potential energy in the compression and heating of the gases in the said part V2 of
the cylinder similarly to the compression of a spring.
If the crank pass the dead point, the gas again expands, and the potential
energy is re-converted into kinetic energy in the mass of the flywheel, by means of
the crank gearing; in the middle position of the piston the potential energy
becomes a minimum and the kinetic energy a maximum. If the piston be then
further moved towards the other end V₁ of the cylinder, compression takes place
there and kinetic energy is converted into potential energy and so forth.
If now the requirement of a constant speed for the flywheel R be abandoned and
the fly-rim be constructed in such a way that, in the middle position of the piston.
at the maximum of the kinetic energy, it contains exactly enough mass to fully
absorb at a given speed the said energy from the expansion action, the kinetic-
energy of the flywheel, or fly-rim will at the end of the stroke be nil.; the potential
energy of the expanded gases will on the other hand be a maximum.
Reversal of movement of the fly-rim R may also take place and the flywheel run.
back until the next change of stroke, and the action be repeated as before at each
to and fro movement of the piston. In both arrangements that is the first the
ordinary one with a revolving flywheel and the second with oscillating fly-rim, a
change of energy takes place and a transference of energy of the "inner work,"
the part producing this being here always the crank mechanism.
If the crank be made to coincide with the centre of the fly-rim, the mass of the
fly-rim will move with the mass of the connecting rod in a straight line instead of
in an arc of a circle; this connecting rod mass may therefore be inserted either in
the piston as a piston mass, or separately in a specially attached body M, Figure 2.
The solution is thereby also afforded of relieving the crank gearing from the
"inner work the conversion of energy for the compressions and equivalent
expansions taking place during one movement of the piston without the supply of
heat, merely in the direction of the axis of pressure of the piston, without a lever
and without a crank gearing.
"
The actual effective work may be delivered to the outside as hitherto by means
of crank gearing or other suitable means.
This is the essential part of the new arrangement for the above mentioned heat
driven engines.
The hereinbefore described to a certain extent ideal form of new engines with
separate conversion of energy for the "inner work" may be arranged in various
ways to meet the requirements of practical construction.
For instance where the so-called four stroke cycle is used, two cylinders Z closed

page_text: at both ends (see Figure 3) or four cylinders closed each at one end only,
(Figure 4) with suitable pistons K are necessary. The pistons which are suitably
inter-connected are either formed of such a mass for a given speed and a given
compressing action as to absorb the energy of the "inner work as hereinbefore
mentioned, or a suitable mass M may be connected to the piston rod.
"
If then the motive fluid, for instance the mixture of gas and air be drawn into
the cylinder V1 (in the first arrangement of two cylinders, Figure 3) to the left of
one piston, be there compressed, be expelled from the left at V³ of the other
piston, be expanded to the right V of the first piston and drawn into the right V
of the second piston or with the other arrangeinent of distributing gear (in the.
second arrangement of four cylinders closed each at one end, Figure 4) if the
mixture be compressed to the left V₁ of the first piston drawn in to the right V2 of
the second piston, expelled from the left V3 of the third piston and expanded to
the right V of the fourth piston, it is evident that according to the action
herein before described, at least two cylinders closed at both ends or four cylinders
closed each at one end must be employed for the four stroke cycle. Alterations in
the load, irregularities in the distribution, in the ignition or in the valve washers,
which all produce a certain inequality of stroke in this arrangement with oscillating
masses and a destruction of the machinery in the case of the inelastic connection of
the piston and the oscillating masses M with the crank gearing, must be provided
for by an elastic connection of the piston and oscillating masses M with the driving
mechanism, for instance by the insertion of a spring F.
This necessity for elastic connection with the driving mechanism which conveys
the useful work, may also be effected by causing the compressed gases themselves,
and not the piston rod, to act as motive power in a special machine D, Figure 5.
In this case, apart from the ordinary distributing devices hitherto employed, the
cylinders Z are suitably connected with a distributing slide, S, so that for instance
(in the first arrangement with two cylinders closed at both ends) gas and air are
compressed to the left V₁ of one piston drawn in to the right V thereof, consumed
and expanded to the right V4 of the other piston and from the left V³ of this latter
the gases of combustion are forced to a compressed air receiver W and to a
machine D which works like an ordinary compressed-air driven engine. The
cooling may take place in front of the receiver W and a preliminary heating
behind the receiver W and before, or in the compressed air engine D with the
object of diminishing the work of compression and increasing the expansion action.
The distribution may also be so arranged that always those cylinders in which
combustion takes place are connected with the compressed air engine D or a part
of the mixture compressed in excess may be allowed to expand towards the said
engine D without ignition, from those cylinders in which compression takes place.
On the next stroke this portion of the mixture may be drawn back towards the
cylinders Z and then after a second compression be exploded therein. If the
mixture be formed only after the compression, the air or the gas may be allowed
to operate separately in the compressed air engine, D.
By alterations in the distribution, the number of the cylinders, and the form and
arrangement of the compressed air engine D, a number of various forms of
construction may be for that matter evolved. It is evident that the conversion
with compressed air may also be carried out with special compressors. Instead of
air, any other suitable gas or liquid may be employed as pressure medium.
If the
reciprocating pistons K (Figure 6) be connected with a reciprocating electric
current producer, for instance an armature A with inducing coils in the field of a
magnet E and the armature coils be connected with an alternating current motor
(if a constant current be used, with a constant current motor) then by means of
this "elastic" electric conversion, energy of movement may be given off as useful
work. By the displacement of the mass which receives the energy of the “inner
work" from the flywheel into the connecting mass, a further step towards
simplification may be made. It has been hereinbefore shown (in Figures 1 and 2)
that by compression in the part V2 kinetic energy was converted into potential

page_text: energy, which on expansion was re-converted into kinetic, and then finally again
into potential energy of the gas compressed in V₁. If the cylinder be now place.l
upright, in place of the potential energy of the expanded gas in the part V there
may be employed the potential energy of the position of the oscillating body or
mass M, because gravity now comes into action.
This arrangement which is shown in Figure 7, may be employed for instance in
connection with the four stroke cycle. A condensed mixture is contained below
one piston at V₁, is consumed and expands below another and upper piston, and
during this process is drawn in first stroke at V2, the pistons K K thus move
upwards with at first an accelerated and then a decreasing speed. On the change
of direction, the energy for the next compression is stored up in the coupling mass
or body M as potential energy. On the descent, compression always takes place
at V below the upper piston, and expulsion at Vi below the lower piston
(preferably forced towards a compressed-air engine D (see Figure 5) second
stroke. On the third stroke combustion and expansion take place at V2 belov
the upper piston, drawing in of the mixture at V₁ below the lower piston, and
so forth. Even here the delivery of useful work may be made electrically
or by compressed air by means of special compressors, or by compressing
in a compressed air engine either combustion gases, or a portion of the compressed
air. In case a compression does not take place, or interruptions in the distribution,
ignition, and so forth, should take place, there must be provided in the machine,
safety devices which render barmless or brake to a certain extent the new energy of
movement of the pistons unconsumed by compression. These devices may consist
of purely mechanical brakes, liquid brakes, air buffers, magnetic brakes, or if an
electric conversion of energy be employed, as shown in Figure 6, of short circuiting
devices for the induced part, so that here, for instance, the kinetic energy is
converted into electricity and heat, and utilised before the piston reaches the
bottom of the cylinder.
Such braking devices (for instance the lever of the short circuiting device) are
operated or released on the stroke being exceeded, by means of the usual mechanical
arrangements, oscillating parts, projections, pins, or by a gas-pressure gauge, which,
on the normal compressing pressure not taking place, acts at the right time on such
braking devices.
In conclusion, the following of other possible modifications of the arrangements
herein before described may be mentioned.-
First, the piston may be stationary and the cylinder reciprocating, in which case
the mass or body M must be connected or united with the cylinder. Further, the
mass M may be connected rigidly or by means of springs with the piston, the piston
rod or the like. Instead of one, several cylinders may be arranged parallel or
concentric to one another, or in series, but always with parallel axes of pressure.
For two cylinders each closed at one end and which open towards one another, a
common plunger may be employed. Instead of the crauk gearing, racks and
ratchet wheels and other like mechanism may be employed for conveying the
effective work.
It is finally immaterial for the essential part of this invention with what kind of
heating material, such as gas, petroleum, or coal dust the heat machine is driven
and how the regulating and distributing devices are arranged.
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. In fluid pressure heat engines having compression of the working fluid, the
arrangement of reciprocating or oscillating masses adapted and intended to absorb
and give up the energy of the "inner work and to replace the rotating masses of
flywheels for said purpose, in order to avoid the loading by said "inner work" of
the crank gearing or like mechanism, substantially as herein before set forth.
2. The combination with an arrangement of reciprocating or oscillating masses

page_text: such as described, of a spring connection to the crank gearing, substantially as set
: set forth.
3. The combination with an arrangement of reciprocating or oscillating masses
such as described of a machine adapted to be driven by compressed air substantially
as and for the purpose set forth.
4. The combination with an arrangement of reciprocating or oscillating masses
· such as described of a reciprocating electric current producer substantially as and
for the purpose set forth.
5. The combination with an arrangement of reciprocating or oscillating masses
such as described of mechanical, maguetic or electric braking devices substantially
- as and for the purposes set forth.
Dated this fith day of December 1805
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Agents for the Applicant.
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Agents for the Applicant.