IMPROVEMENTS IN GAS ENGINES
Year: 1884

page_text: I CHARLES MAX SOMBART of the firm of Buss Sombart and Company of Magde-
burg in the Empire of Germany do hereby declare the nature of said Invention for
"IMPROVEMENTS IN GAS ENGINES" to be as follows :-
The present Improvements relate partly to gas motor Engines which have two
cylinders one for the compression of gas and air and the other in which tho
explosion of this compressed inixture takes place at the moment when the motor
piston is in its lowest position and the Invention also relates as far as the regulation
and ignition are concerned, to gas Engines generally.
The improvements consist (1) In obtaining an advance or lead of the com-
pression piston in relation to the motor piston by means of the coupling of both
the connecting rods to one common crank pin and by the oblique arrangement of
the compression cylinder behind the motor cylinder.
2. In the construction of the back pressure valve.
3. In the construction of the gas and air valve.
4. In the application of a separato valve for and the manner of regulating the
working of the gas Engine and
5. In the Ignition device.
The vertical frame of the Engine is cast separately or in one piece with both the
motor and the compressing cylinders and carries at the top of its upright extensions
the crank shaft which is joined to the motor piston by the ordinary connecting rod.
The piston of the compressing cylinder is connected thereto by another rod which
is pivoted to the head of the rod of the piston of the motor cylinder In arranging
thus the connecting rods an advance of the crank of the compressing cylinder in
relation to that of the motor cylinder is obtained if the fly wheel be turned in the
direction in which the compression cylinder is situated.
The igniting slide valve moved by a rod connected to a crank disc which is
keyed upon the end of the crank shaft. The exhaust valve is dispensed with and
an outlet orifice tube only is used The orifice leading to this tube is so arranged
in the motor cylinder that it is nearly entirely uncovered by the motor piston when
the latter occupies its bighest position. At this position the products of combustion
having a higher tension than the atmospheric air, are expelled as long as there is
any difference of pressure between the inside and outside of the motor cylinder.
The gas and air valves as usually used in other gas engines are constructed either
with two seats or each separately.

page_text: Separate valves are complicated and double seated valves are subjected to great
irregularities on account of the-seats wearing out unequally so that ultimately the
valves do not close perfectly.
These inconveniences are obviated by the following construction of admission
valve which has one seat only for the passage of air and gas and is so constructed
that the gas is shut off from the air by a cylindrical part attached to the valve
which part is provided with slots for the passage of gas when the valvo is raised
and which serves at the same time as a guide for the valve.
It is a well known fact that the mixture of gas and air in passing from a com-
pression cylinder to the motor cylinder deposits grease on the back pressure valve
as now in use The said grease is then burnt by the hot gases of the explosion
and ultimately covers tho valve with a hard layer which prevents it from closing
tightly.
In order to avoid the formation of such a layer the valve is arranged within a
metallic wire cloth which prevents the flame of the explosion from reaching it.
A small valve is provided for regulating the speed or working of the gas Engine
by controlling the admission of gas to the motor cylinder. It is operated upon by
the action of a governor placed on the outside of the compressing cylinder, the said
Governor consists of a pendulum mechanism which is arranged in a cylindrical case
and the deviations of the pendulums are transmitted through a rod acting upon an
angle lever connected by a rod with the said small valve.
When the gas engine runs at its normal speed the valve is always kept open but
as soon as it exceeds this speed the said valve is entirely closed so that air only can
enter the compression cylinder and as the space below the valve communicates
with the inside of the compressing cylindor, the said valve is pressed tightly upon
its seat during the sucking action of the compressing piston so that no leakage of
gas can take place.
The ignition device is based upon the principle of the one described in the
Specification of British Patent No 1997/78 but with the difference that the pressure
reduction nozzle pipe through which passes a part of the compressed mixture from
the motor cylinder through the small channel into the aperture of the slide valve,
is not of conical, but of a small and long cylindrical shape leading nearly to the
bottom of the opposite conical bore. By this the pressure of the ignition mixture
is not only more properly reduced but it also fills entirely the aperture of the slide
valve and consequently the ignition through the constantly burning flame is better
secured.
The Engine works in the following manner
During the upstroke of the compression piston gas and air are drawn in through
the selfacting valve in such a proportion as to obtain a highly explosive mixture.
At the downstroke this mixture is compressed and forced through the back pressure
valve into the motor cylinder. The discharge of the burnt gases through the outlet
tube takes place during a short time only when the motor piston is nearly about
to change the direction of motion at the upper dead point These gases escape by
virtue of the surplus of pressure which they have in relation to the atmospheric
pressure at the end of the upstroke. As soon as the pressure inside and outside of
the cylinder is counterbalanced the motor piston will again cover the exhaust
opening during the downstroke.
By this arrangement nearly the whole volume of the motor cylinder is kept filled
with burnt gases which are compressed during the downstroke. As at the same time
the mixture of fresh air and gas from the compression cylinder is pressed into the
motor cylinder at the lower end, the said burnt gases are thus forced into the
hollow part of the motor piston while the good explosive mixture rests at
the bottom and in the oblique channel leading to the opening of the igniting slide
valve.
This arrangement is chosen on account of its great simplicity and because the
consumption of gas is reduced by it. But of course the exhaust could be also
arranged in the manner described in the provisional Specification of the Application

page_text: for Patent No 2057/ without affecting the other parts of the Engine or their
working.
The ignition of the mixture in the motor cylinder is effected when the motor
piston occupies its lower dead point. As the said piston reaches this point when
the compressing piston has already commenced its upstroke it is evident that the
back pressure valve must always be closed at the moment of the explosion taking
place so that ignition in the compressing cylinder can never take place.
Dated 26th day of 100
I, CHARLES MAX SOMBART of the Firm of Buss Sombart and Company of
Magdeburg in the Empire of Germany do hereby declare the nature of my
invention for "IMPROVEMENTS IN GAS ENGINES" and in what manner the same
is to be performed, to be particularly described and ascertained in and by the.
following statement :—
The present Improvements relate partly to Gas Motor Engines which have two
cylinders one for the compression of gas and air and the other in which the
explosion of this compressed mixture takes place at the moment when the motor
piston is in its lowest position and the said Invention also relates as far as the
regulation and ignition are concerned to Gas Engines genorally.
My improvements as hereinafter described consist in, Firstly, obtaining an
advance or lead of the compression piston in relation to the motor piston by means
of the coupling of both the connecting rods to one common crank pin and by the
oblique arrangement of the compression cylinder behind the motor cylinder-
Secondly, in the construction of the back pressure valve, Thirdly, in the con-
struction of the gas and air valve Fourthly in the application of a separate valve
for and the manner of regulating the working of the gas engine Fifthly in the
ignition device and lastly in an arrangement for facilitating the starting of the gas
engine.
Figures 1, 2 and 3 of the accompanying drawings represent a front and side.
elevation and a plan of a gas motor engine constructed according to this Invention,
Figure 4 represents drawn to a larger scale the gas and air valvo with the
regulating valve. Figure 5 shows the back pressure valve and Figure 6 shews a
device inside the igniting valve for establishing an intermitting flame-Figures 1ª
and 1b show an arrangement for facilitating the start. of the gas engine with two.
cylinders if an exhaust valve be operated upon.
The vertical frame A is cast separately or in one piece with both the motor
cylinder B and the compressing cylinder C and carries at the top of its upright.
extensions the crank shaft D which is joined to the motor piston F' by the ordinary
connecting rod a The piston G of the compressing cylinder is connected thereto
by the rod b which is pivoted to the head of the rod a (Figures 1 and 2) In thus
Arranging the connecting rods, an advance of the crank of the compressing cylinder.

page_text: in relation to that of the motor cylinder is obtained if the fly-wheel be turned in
the direction indicated by the arrow in Figure 2.
The igniting slide valve H is moved by a rod d jointed to the pin c of the disc e
which is keyed upon the end of the crank shaft D. The exhaust valve can bo
dispensed with and an outlet orifice and tube f'f only bo used. The orifice f¹
leading to this tube is so arranged in the motor cylindor that it is nearly entirely
uncovered by the motor piston F (Figure 2) when the latter occupies its highest
position. At this position the products of combustion having a higher tension than
the atmospheric air are expelled as long as there is any difference of pressure
between the inside and outside of the motor cylinder B.
The gas and air valves as usually used in other gas engines are constructed
eithor with two seats or each separately. Seporate valves are complicated and
double seated valves are subjected to great irregularities on account of the seats
woaring out unequally so that ultimately the valves do not closo perfectly. These
inconveniences are obviated by the following construction of the admission valve I 1
which has one orifice and valve seat only for the passage of both the air and gas
and is so constructed that the gas is shut off from the air by the cylindrical part g
attached to the valve, which cylindrical part is provided with slots g¹ for the
passage of gas when the valve is raised and serves also as a guide for the valvo.
It is a well known fact that the mixture of gas and air in passing from a coin-
pressing cylinder to the motor cylinder deposits grease on the back pressure valve
as now in use. The said grease is then burnt by the hot gases of the explosion
and ultimately covers the valve with a hard layer which prevents it from closing
tightly.
In order to avoid the formation of such a layer the valve K. (figure 5), is i
arranged within a metallic wire cloth which prevents the flame of the explosion
from reaching it.
A small valve (figures 2 and 4) serves for regulating the speed or working of
the gas engine by controlling the admission of gas to the motor cylinder. The said
valve is operated upon by the action of the governor L placed on the outside of
the compressing cylinder C. The said governor consists of a pendulum mechanism
which is arranged in a cylindrical case and the deviations of the pendula are
transmitted through a rod acting upon the angle lover and rod h², figures 1 and 2
connected to tho said small valve. When the gas engine runs at its normal speed
the valve is always kept open but as soon as it exceeds this speed the said valve h
is entirely closed so that air only can enter the compression cylinder and as the
space below the valve communicates with the inside of the compressing cylinder,
the said valve his pressed tightly upon its sent during the sucking action of the
compressing piston so that no leakage of gas can take place.
The ignition device is based upon the principle of the one described in the
Specification of British Patent No 1997 of 1878, but with the difference that
the pressure reduction nozzle pipe through which a part of the compression
mixture from the motor cylinder passes through the small channel o (figure 6) into
the aperture of the slide valve, is not of a conical shape but of a small and long
cylindrical shape leading nearly to the bottom of the opposite conical bore k¹ By
this means the pressure of the ignition mixture is not only moro properly reduced
but it also fills entirely the aperture and consequently the ignition through the
constantly burning flame is better secured.
The engine works in the following manner: During the upstroke of the com-
pression piston G gas and air are drawn in through the self-acting valve I in such
relative proportions as to obtain a highly explosive mixture. At the downstroke
this mixture is compressed and forced through the back pressure valve K into the
motor cylinder B. The discharge of the burnt gases through the tube f takes
place during a short time only when the motor piston F is nearly about to change
the direction of motion at the upper dead point figure 2ª. These gases escape by
virtue of the surplus of pressure which they have in relation to the atmospheric
pressure at the end of the upstroko, As soon as the pressure inside and outside of
1

page_text: the cylinder is counterbalanced the motor piston will again cover the exhaust
opening f¹ during the downstroke.
By this arrangement nearly the whole volume of the motor cylinder is kept filled
with burnt gases which are compressed during the downstroke. As at the same
time the mixture of fresh air and gas from the compression cylinder is pressed into
the motor cylinder at the lower end, the said burnt gases are thus forced into the
hollow part of the motor piston F (6gure 2) while the good explosive: mixture
rests at the bottom and in the oblique channel leading to the opening p of the
igniting slide valve plate q, figure 6.
This arrangement is chosen on account of its great simplicity and because the
consumption of gas is reduced by it. But of course the exhaust could be also
arranged in the manner as described in the provisional specification of the
application for Patent No 2057 of 1882 without affecting the other parts of the
engine or their working.
In this case it would be preferable in order to facilitate the start of the
gas engine to apply a second cam a¹ (figure 1b) to the cam b¹ for actuating the
exhaust valve M (figure 1). These two cams are arranged on the same sleeve E,
and can be displaced by being moved longitudinally upon the crank shaft end by
means of the lever i or by other convenient means. The second cam a! has a longer
rolling surface than the cam b¹ so that when the friction' roller g³ of the exhaust
valve rod g³ rolls upon it, the burnt gases can escape during a greater portion of
the stroke of the motor piston than would be the case if the cam b¹ (figure 1b)
acted thereon. Therefore in order to facilitate the start of the gas engine, that is to
say, to expend less power in moving the fly wheel of the motor by hand, it is
necessary that the cam a' acts upon the roller g³ for the purpose of avoiding a
great compression of the remains of the mixture of gas and air in the working
cylinder. After the engine is fairly in motion the sleeve E is shifted by means of
the lever i so as to cause the cam a¹ to leave its bearing on the roller g³ and the
cam b' to take its place.
The ignition of the mixture in the motor cylinder is effected when the motor
piston occupies its lower dead point. As the said piston reaches this point when
the compressing piston has already commenced its upstroke it is evident that the
back pressure valve K must always be closed at the moment of the explosion taking
.place so that an ignition of the contents of the compressing cylinder can never take
place.
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 gas motor engines with two cylinders, the one being the explosion, or
motor cylinder and the other being the compression cylinder, the inethod of
obtaining an advance or lead of the piston of the compressing cylinder in relation
to that of the motor cylinder, substantially as hereinbefore described.
Second-The oblique arrangement of the compression cylinder C behind the
motor cylinder B, in combination with the coupling of the connecting rod 6 to the
connecting rod a, which latter alone is attached to the crank of the shaft
D, substantially as hereiubefore described and illustrated by the accompanying
drawings.
Third: The construction of the back pressure valve K provided with a metallic
wire cloth, within which the valve is arranged, substantially as hereinbefore
described and illustrated in the accompanying drawings.
Fourth-The construction of a gas and air valve I having only one seat,
the valve proper closing and opening at the proper times the entry for both air
and gas, the said valve proper being provided with a cylindrical part or socket y
with slots g', which serve both for closing the gas way and as a guide for the
valve, substantially as hereinbefore described and illustrated in the accompanying
drawings.

page_text: Fifth-The means for regulating the speed or working of gas motor engines,
consisting in the combination of a governor with the lever h¹, rod h³, and gas valvo
h, which is alosed by the action of the governor when the gas engine, runs too
fast, and which if closed is kept tight upon its seat by the sucking action of the
ascending compression piston, substantially as herein before described and illustrated
by the accompanying drawings.
Sixth-In an ignition device based on the principle of that described in the
Specification of the Patent No 1997 of One thousand eight hundred and seventy
eight, the employment of a long cylindrical pressure reducing nozzle pipe / leading
into an opposite conical boro k¹, substantially as and for the purpose herein before
described and illustrated by the accompanying drawings.
Seventh-The general arrangement and combination of parts constituting the gas
engine, substantially as hereinbeforo described and illustrated in the accompanying
drawings.
Dated this 13th day of December One thousand eight hundred and eighty four.