Improvements in or relating to Internal Combustion Engines.
Year: 1898

page_text: Date of Application, 2nd Aug., 1898
Complete Specification Left, 2nd May, 1899-Accepted, 22nd July, 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to Internal Combustion Engines.
A communication from CARLOS MENDIZABAL, of Bilbao, in the Kingdom of
Spain, Engineer
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be
as follows:-
Internal combustion engines, such as gas motors have hitherto had many
drawbacks, the most important among which are:
1. To enable the cylinder to be lubricated in spite of the high temperature of
the products of combustion, its walls must be cooled by surrounding them with
water, whereby 40%-50% of the heat developed by combustion become a pure
loss.
2. The small expansion of the products of combustion results in their escaping
at high temperature, which is a second cause of loss of energy, to be added to
the first. The greatest part of the total loss of caloric energy which is not less
than 80% in the best motors, is chiefly due to these two causes.
3. Only one stroke of the piston, out of two, is operative in motors of the
Letombe description, or one in four in Otto cycle motors, or one in six in the
Griffin type of motor. The result is that the motion is irregular, in spite of
very heavy fly wheels being used, and a double, quadruple or sextuple piston
area is required as compared to that required to develop the same power with
a double acting motor. Gas motors are therefore heavier, more expensive and
take up more room than would be the case if they were double-acting.
4. The difficulty of reversing renders the application of these motors for
locomotion and navigation impossible or very difficult.
These drawbacks must be remedied before internal combustion engines can be
used instead of steam engines for all purposes.
The following means have been devised for this purpose according to this -
invention.
1. In order that the cooling of the products of combustion which is always
necessary, should not be a source of loss of energy, their excess of heat must be
taken from them by a body capable of transforming said heat into mechanical
energy.
For this purpose, as will be hereinafter explained the combustion should take
place not in the motor-cylinder, but in a separate chamber where these products
become mixed with a sufficient quantity of inert gases to absorb the excess of
heat. The weight, pressure and temperature of these gases relatively to the
explosive mixture being suitably calculated, an active mixture can be obtained,.
the temperature of which enables the cylinder to be properly lubricated, and the
pressure of which is very high.
2. The expansion of the driving mixture in the cylinder must be sufficient to
reduce its temperature and pressure approximately, to that of the atmosphere.

page_text: It will therefore be necessary to start from the maximum pressure correspond-
ing to the temperature enabling the cylinder to be lubricated, and to calculate
the expansion of the gases so as to reduce said pressure. and temperature to the
desired point..
3. It is easy to adopt the usual arrangement of double acting steam engines,
and to supply gases and air by means of pumps arranged as a continuation
of the motor cylinder, or in other position, or even provided with a separate
motor in case of large engines. This combination of well known means will
give two operative driving, strokes per revolution.
2
To enable the engine to be reversed, it must be done as easily as in steam
engines, where. it is only necessary to open a valve.
For this purpose it will be sufficient to suppress ignition during one revolution
and to close, after this revolution, all gas- and air-inlets.
After the stoppage, the combustion chambers (hereinafter described) will
remain full of compressed explosive mixture, and it will only be necessary, in
order to start the motor in the desired direction, to ignite the explosive mixture
contained in the combustion chamber arranged at that end from which the
driving effort is to proceed.
The first half revolution having been, effected, the mixture in the second
chamber will produce the driving effort, while the first chamber will become
filled again, and the operations will continue in the usual manner.
To reverse during working, that is to say in the same way as in steam engines,
it will be necessary to deliver the gas collected by the front pump. into the back
combustion chamber, and vice versa. The explosion will have to take place after
the exhaust valve has been closed, and the piston will exercise compression on
the active mixture. The latter will be released when the piston arrives at the
dead point, in order that no motive work be developed.
The principles underlying the working of this motor having been described,
it remains now to describe as an example, a construction of such an engine.
The engine comprises a motor-piston provided on both sides with solid pistons
in line with the main piston. These two pistons work in two pump bodies
formed on the cylinder covers, and act as plungers.
The front piston is provided with a rod or extension projecting outside
through a metallic stuffing box, and with the usual cross-head, guides etc.
Towards the bottom of each pump-body a valve opens to the outside admitting
mixture of gas and air. The opening of this valve is effected by a lever and cam
mounted on a longitudinal shaft driven from the driving shaft at the same speed
as the latter.
The mixture of gas and air is effected in a chamber arranged behind the
admission valve. When the latter is open, the driving piston moves back and
draws said mixture into the pump-body. Air enters through ports open to the
outside, and gas passes through a valve arranged on a spindle supporting the
inlet valve.
The volume of the mixture drawn in depends on the time during which the
valves remain open, and this time is regulated by a centrifugal governor arranged
on the distributing shaft. The governor moves the shaft forward and backwards,
and the cams accordingly release the valves earlier or later, the valves being
returned to their seats by springs.
The mixture drawn in during a portion of the stroke during which the valves
remained open, expands until the end of the stroke and is afterwards compressed
by the return of the piston which forces: it into the combustion chamber
separated by an automatic valve from the pump body.
Shortly after the crank has passed the dead point, the mixture is ignited,
say by an electric spark, and the products of combustion open an automatic
valve and become mixed with inert gases stored up, as will be hereinafter
described, in the mixing chamber: The mixture resulting therefrom has the
desired temperature and pressure to allow of lubricating, and expands, power

page_text: being developed, up to the end of the stroke, the pressure and the temperature
being lowered by this expansion approximately to that of the atmosphere.
When the piston has reached about the half the length of the motor cylinder
the exhaust valve opens in its lower part, under which is a chamber closed by a
valve on the exhaust pipe. This valve is raised by the shaft of the distributor
at the end of each course, the expanded gas being thus enabled to escape during
a little less than half the return stroke.
When the edge of the piston has passed the edge of the exhaust port it closes
it, and the valve closes at once, to prevent the mixture on the other side of
the piston from escaping after the latter has passed beyond the exhaust port.
The inert gases thus enclosed in front of the piston are forced by the latter
into the mixing chamber where they are heated, when having passed the dead
point, they will receive the products of combustion of the explosive mixture,
contained in the combustion chamber.
The cycle of the motor is therefore, beginning from the dead point as
follows:
1. The combustion chamber is filled with compressed explosive mixture. The
mixing chamber and the clearance are filled with compressed inert gases.
2. After the advance movement. of the piston has commenced, the mixture
is ignited in the combustion chamber and its products, mixed with inert gases,
produce the motive mixture.
3. The latter pushes the piston forward. The piston of the pump draws in,
as soon as the inlet valve has been opened, the explosive mixture for the next
stroke, until said valve closes, whereby the volume admitted is regulated accord-
ing to the speed of the motor.
4. The forward stroke of the piston having been finished, the exhaust valve
opens and allows the gases to escape, until the exhaust port. is closed by the
piston, whereupon the valve immediately closes.
5. The compressed inert gases are in the mixing chamber, while the explosive
mixture is forced into the combustion chamber.
This cycle is repeated, at intervals of half a revolution, at the other side of
the driving piston.
Dated this 2nd day of August 1898.
BOULT & WADE,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Internal Combustion Engines.
A communication from CARLOS MENDIZABAL, of Bilbao, in the Kingdom of
Spain, Engineer
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent,- 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:--
Internal combustion engines, such as gas motors have hitherto had many
drawbacks, the most important among which are:-
1. To enable the cylinder to be lubricated in spite of the high temperature of
the products of combustion, its walls must be cooled by surrounding them with
water whereby 40% to 50% of the heat developed by combustion become a pure
loss.

page_text: 2. The small expansion of the products of combustion results in their escaping
at a high temperature, which is a second cause of loss of energy, to be added to
the first. The greatest part of the total loss of caloric energy-which is not less
than 80% in the best motors, is chiefly due to these two causes.
3. Only one stroke of the piston, out of two, is operative in motors of the
Letombe description or one in four in Otto cycle motors, or one in six in the
Griffin type of motor. The result is that the motion is irregular, in spite of
very heavy fly wheels being used, and a double, quadruple or sextuple piston
area is required as compared to that required to develop the same power with
a double acting motor. Gas motors are therefore heavier, and more expensive, and
take up more room than would be the case if they were double-acting.
4. A reversal of movement is impossible without the use of special forms of
gearing. This renders the application of these motors for locomotion and navi-
gation impossible or very difficult.
These drawbacks must be remedied before internal combustion engines can be
used instead of steam engines for all purposes.
The following means have been devised for this purpose according to this
invention.
1. In order that the cooling of the products of combustion, which is always
necessary, should not be a source of loss of energy, their excess of heat must be
taken from them by a body capable of transforming said heat into mechanical
energy.
For this purpose, as will be hereinafter explained, the combustion should take
place not in the motor-cylinder, but in a separate chamber, where these products
become mixed with a sufficient quantity of inert gases to absorb the excess of
heat. The weight, pressure and temperature of these gases relatively to the
explosive mixture being suitably calculated, an active mixture can be obtained,
the temperature of which enables the cylinder to be properly lubricated, and the
pressure of which is very high.
2. The expansion of the driving mixture in the cylinder must be sufficient to
reduce its temperature and pressure approximately to that of the atmosphere.
It will therefore be necessary to start from the maximum pressure correspond-
ing to the temperature enabling the cylinder to be lubricated, and to calculate
the expansion of the gases so as to reduce said pressure and temperature to the
desired point.
33. It is easy to adopt the usual arrangement of double acting steam engines,
and to supply gases and air by means of pumps arranged as a continuation
of the motor cylinder, or in other position, or even to provide a separate motor
in case of large engines. This combination of well known means will give two
operative driving strokes per revolution.
To enable the movement to be reversed, the motor must first be provided with
means for starting as easily as is done in steam engines, where it is only
necessary to open a valve.
For this purpose it will be sufficient to suppress ignition during one revolution
and to close, after this revolution, all gas and air inlets.
After stoppage, the combustion chambers (hereinafter described) will remain
full of compressed explosive mixture, and it will only be necessary, in order to
start the motor in the desired direction, to ignite the explosive mixture contained
in the combustion chamber arranged at that end from which the driving effort
is to proceed.
The first half revolution having been effected, the mixture in the second
chamber will produce the driving effort, while the first chamber will become
filled again, and the operations will continue in the usual manner.
To reverse during working, that is to say in the same way as in steam engines,
it will be necessary to deliver the gas collected by the front pump into the back
combustion chamber, or vice versa. The explosion must take place after the
exhaust valve has been closed, and the piston will exercise compression on the

page_text: chamber closed by a valve u on the exhaust passage v. This valve u Figure 4
is raised by the shaft ; of the distributor at the end of each course, the expanded
gas being thus enabled to escape during a little less than half the return stroke.
When the edge of the piston has passed the edge of the exhaust ports it
closes it, and the valve closes at once, to prevent the mixture on the other
side of the piston from escaping after the latter has passed beyond the exhaust
port.
The inert gases thus enclosed in front of the piston, are forced. by the latter
into the mixing chamber wo where they are heated, when the dead point having
been passed they will receive the products of combustion of the explosive
mixture, contained in the combustion chamber q.
The cycle of the motor, is, therefore, beginning from the dead point as
follows:-
1. The combustion chamber is filled with compressed explosive mixture.
The mixing chamber w and the clearance are filled with compressed inert gases.
2. After the advance movement of the piston has commenced, the mixture
is ignited in the combustion chamber q and its products, mixed with inert
gases, produce the motive mixture.
3. The latter pushes the piston a forward. The piston 6 (or c) of the pump
draws in, as soon as the inlet valve has been opened, the explosive mixture
for the next stroke, until said valve closes, whereby the volume admitted is
regulated according to the speed of the motor.
4. The forward stroke of the piston a having been finished the exhaust valve u
opens and allows the gases to escape, until the exhaust port is closed by the
returning piston a whereupon the valve immediately closes.
5. The inert gases are compressed in the mixing chamber while the explosive
mixture is forced into the combustion chamber q.
This cycle is repeated, at intervals of half a revolution, at the other side of
the driving piston.
For reversing any suitable means may be employed for effecting the non-
working of the ignition device, during one revolution, and the subsequent closing
of the gas and air inlets.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondent, and in what
manner the same is to be performed, I declare that what claim is:-
1. The use of inert gases for absorbing the excess of heat of the products of
combustion and transforming it into useful work on the piston, substantially as
described.
2. An internal combustion motor with a double cylinder capable of being
started without additional devices or operations, and of working in either
direction substantially as described.
3. The method of obtaining two driving efforts per revolution substantially as
described.
4. In an internal combustion engine a mixing and explosion chamber sub-
stantially as described or illustrated, in Figures 7 and 8 of the accompanying
drawings.
5. An internal combustion engine comprising a cylinder with a piston such
as abc, a central exhaust ports, and valves at the ends of the cylinder ex-
tensions, substantially as described.
6. An internal combustion engine substantially as described or illustrated in
the accompanying drawings.
Date : 01
1 1000

page_text: active mixture. The latter will be released when the piston arrives at the dead
point, in order that no motive work be developed.
The principles underlying the working of this motor having been described,
it remains now to describe as an example, a construction of such an engine.
Figure 1 is an elevation;
Figure 2 an end view;
Figure 3
front view, and
Figura 4 a section through the exhaust valve, of a motor constructed accord-
ing to this invention.
Figure 5 is a longitudinal section;
Figure 6 a plan of the motor, and
Figures 7 and 8 show details of the mixing and combustion chambers, on a
larger scale.
The engine comprises a motor-piston a provided on both sides with solid
pistons be in line with the main piston. These two pistons bc work in two
pump bodies ed formed on the cylinder covers or extensions, and act as plungers.
The front piston c is provided with a rod for extension projecting outside
through a metallic stuffing box, and with the usual cross-head, guides etc.
Towards the bottom of each pump-body a valve m opens to the outside for
admitting a mixture of gas and air. The opening of this valve is effected by
a lever and cam mounted on a longitudinal shaft driven from the driving
shaft at the same speed as the latter.
The mixture of gas and air is effected in a chamber k arranged behind the
admission valve m. When the latter is open, the driving piston moves back and
draws said mixture into the pump-body. Air enters through ports 11 open to
the outside, and gas passes by a valve g arranged on a spindle supporting the
inlet valve m.
The volume of the mixture drawn in depends on the time during which the
valves remain open, and this time is regulated by a centrifugal governor o
arranged on the distributing shaft j. The governor o moves the shaft forward
and backwards, and the cams accordingly actuate the valves earlier or
later, the valves being returned to their seats by springs p.
The mixture drawn in during a portion of the stroke during which the
valves g g remained open, expands until the end of the stroke and is afterwards
compressed by the return of the piston which forces it into the combustion
chamber separated by an automatic valve from the pump body b or c.
Shortly after the crank has passed the dead point, the mixture is ignited say
by an electric spark, and the products of combustion open an automatic valve
and become mixed with the inert gases stored up, as will be hereinafter described,
in the mixing chamber c.
The mixture resulting therefrom has the desired temperature and pressure
to allow of lubricating, and expands, power being developed, up to the end of
the stroke, the pressure and the temperature being lowered by this expansion
approximately to that of the atmosphere.
The combustion chamber y should be of variable volume, so as to secure a.
constant pressure for the combustible mixture stored up, in spite of the different
volumes there might be from one moment to another.
For this purpose this chamber which is preferably cylindrical in form and
open at the top, is provided with a piston or disc (y) which fits it with slight.
friction.
The lower part of this piston is subject to the pressure of the stored up com-
bustible mixture, as described the upper part to the pressure of the stored up.
inert gases in the mixing chamber, and the piston will occupy a position in
harmony with the equilibrium of these two pressures and the pressure of the
combustible mixture will therefore always remain the same.
When the motor piston has travelled about half the length of the motor-
oylinder the exhaust valve s in its lower part opens, under which valve is a