Improvements in Gas and Oil Motor Engines.
Year: 1892

page_text: Date of Application, 19th July, 1892
Complete Specification Left, 15th Mar., 1893-Accepted, 13th May, 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE GAS MOTOREN FABRIK DEUTZ, of Kocln-
Deutz, Germany, Manufacturers.]
Improvements in Gas and Oil Motor Engines.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Chartered Patent Agent, do hereby declare the nature
of this invention to be as follows:-
This invention relates to an improved construction of gas and oil motor engines
working with a two-stroke cycle, whereby only a certain portion of the ontstroke of
the piston is made to constitute the working stroke during which the combustion
gases resulting from the previously fired combustible charge are expanded, after
which, during a further portion of the outstroke, the combustion gases under
pressure are caused to escape so as to leave only gases at or about atmospheric
pressure in the cylinder, while during the last portion of the outstroke, according
to one arrangement, the combustible charge is drawn in, which charge, together
with the residue of combustion gases is then compressed by the following instroke
in order to be fired when the piston arrives at the dead centre. Or, according to
another modification, only atmospheric air is drawn in during the last part of the
outstroke, and the combustible gas, vapour, or spray is introduced under pressure
during the compressing instroke.
For carrying out the first above described method of working, the arrangement
of the engine may be as follows. The cylinder has at its inner end a discharge
valve for the combustion gases and a valve for admitting the explosive mixture of
gas or combustible vapour or spray and air, and it is also provided with any
suitable known igniting arrangement. The discharge and gas valves are operated
by cams on a way shaft that is driven from the crank shaft at the same speed, the
said valves being operated by their cams in such a manner that when the piston
has been propelled through a portion of its outstroke, the discharge valve is opened
for a short period so as to allow of the escape of the combustion gases under
pressure, after which it is made to close, and the gas valve is opened so as to cause
a combustible mixture of gas or vapour or spray and air to be drawn in during the
remainder of the outstroke. The piston then performs its instroke, thereby com-
pressing the charge, and when it has arrived at the dead centre, the charge is fired
by the igniting device. The regulation of the engine can be effected in any known
manner, such as by entirely cutting off or by reducing the supply of combustible
gas when the engine is running too fast. For reducing the gas supply for this
purpose, the cam actuating the gas valve can be formed with a sloping face and be
mounted upon a sleeve sliding on the way shaft and actuated by a governor so as to
cause the cam to operate with a longer or shorter dwell upon the gas valve,
according as the speed of the engine is below or above the normal.
The regulation of the power can also be effected by arranging the cam that
actuates the discharge valve in connection with the governor, so as to cause it to be
held open for a longer or a shorter time and thus correspondingly increase or
reduce the time during which the combustible mixture for the explosive charge is
drawn in.
The passage through which the combustion gases escape from the discharge valve
is by preference provided with a check valve in order to prevent the combustion
gases from being drawn back into the cylinder in the event of a partial vacuum
being formed in the cylinder before the discharge valve is closed.
According to another arrangement, operating according to the second above
described method, the cylinder is provided, in addition to the above mentioned

page_text: discharge valve, with an inlet valve for atmospheric air, and the inlet valve and
port for combustible gas, vapour, or spray is connected to any suitable apparatus
for supplying gas, vapour or spray under pressure, the said valve being so con-
trolled by a cam as only to admit the gas &c. under pressure during the compressing
instroke of the piston. Thus during the first part of the outstroke, the piston will
as before be propelled by the expanding gases, until the discharge valve is opened
so as to allow these gases to escape; on the closing of this valve the further motion
of the piston will cause air to be drawn into the cylinder through the before
mentioned inlet valve until the end of the stroke. During the first part of the
return stroke the discharge valve is again opened so as to allow a portion of the
charge of combustion gases and air to be discharged, after which the remainder of
the charge is compressed while at the same time the gas or oil supply valve is
opened so as to cause gas or oil vapour or spray to be forced under pressure into
the cylinder to form the explosive charge which is ignited when the piston arrives
at the dead centre.
The before mentioned discharge of a portion of the combustion gases and air
during the compression stroke may be dispensed with and the whole charge be
compressed.
It will also be evident that if, during the first part of the outstroke the expansion
and cooling of the combustion gases takes place to such an extent as to reduce their
pressure to that of the atmosphere, it will not be necessary to open the discharge
valve during such stroke at all, in which case the drawing in of the charge of air
would follow on immediately after such expansion, a portion of the combustion
gases and air being in that case expelled during the first part of the return stroke
as described.
Dated th 101 1...
T..L.. 1000
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Gas and Oil Motor Engines.
1, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, 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:-
This invention relates to an improved construction of gas and oil motor engines
working with a two-stroke cycle, whereby only a certain portion of the outstroke
of the piston is made to constitute the working stroke, during which the combustion
gases resulting from the previously fired combustible charge are expanded, after
which during a further portion of the outstroke the combustion gases under
pressure. are caused to escape, so as to leave only gases at or about, atmospheric
pressure in the cylinder, while during the last portion of the outstroke according
to one arrangement the combustible charge is drawn in, which charge together with
the residue of combustion gases remaining in the cylinder, is then compressed by
the following instroke, in order to be fired when the piston arrives at the dead
centre.
According to another arrangement only air is drawn in at the last part of the
stroke and the combustible charge is forced in during the compressing stroke.
Sheet of the accompanying drawings shews the improved construction of a gas
or oil motor engine for carrying out the above described mode of working.
Fig. 1. shews a longitudinal section of the engine. Fig. 2 shews a side view.
Fig. 3 shews an end view.
Figs. 4 and 5 shew detached view of the cams, and Fig. 6 a diagram of the
action.
A is the engine cylinder, B the piston, C the crank-shaft, a the discharge valve,

page_text: d a check valve in the discharge passage, is the gas supply valve and e the mixing
inlet valve for the admission of air and of combustible mixture.
Referring to Fig. 6, assuming the firing of the charge to take place when the
crank is at the dead centre at point I, (the charge having been previously com-
pressed), thep during the motion from I to II, the highly heated combustion gases
expand and propel the piston which imparts a corresponding momentum to the fly
wheel, that enables the further movements of the piston to be effected. At point II
the discharge valve a is opened for a short time, say during the travel from II to III,
thereby enabling the combustion gases to escape until those remaining in the
cylinder are about at atmospheric pressure. As it is difficult to determine the exact
duration of this period, and as by the expansion and cooling of the gases the
pressure might sink below that of the atmosphere before the discharge valve is
closed again, thereby causing a portion of the combustion gases to be drawn back
into the cylinder, this is prevented by providing in the discharge conduit behind
the valve a Fig. 1 a check valve d that would prevent any such backward flow of
the gases.
When the crank has arrived at point III, and the pressure in the cylinder is at
or about that of the atmosphere, the discharge valve is closed, and the mixing inlet
valve e for explosive gaseous mixture opens against the action of a spring in con-
sequence of the partial vacuum produced by the onward motion of the piston, so
that a charge of such mixture now enters the cylinder behind the body of combustion
gases still contained therein, such entrance continuing till the end of the outstroke,
at point IV, is reached. The crank now performs its second half-revolution IV to I
compressing the cylinder charge produced as above described, until when arrived at
the dead centre I, the charge is ignited, and so on continuously, so that the engine
works with a cycle of two strokes.
For working in the above described manner, the valve a and the gas supply
valve g are worked by cams n n', on a counter shafts which is driven at the same
speed as the engine shaft C by mitre wheels D, the discharge valve being actuated
by cam n and lever Z with roller o while the gas supply valve is actuated by the
cam n and lever Z' with roller o¹.
The regulation of the speed of the engine can be effected in any of the known
ways such as either by entirely cutting off the gas supply during one or more out-
strokes, when the engine is running too fast, so that there is no power developed
during such strokes, or by decreasing the quantity of combustible gas for the
charge, or by decreasing the total amount of the charge, these methods being
effected by opening the gas valve g for a shorter time, or by shortening the charging
period by keeping the discharge valve open for a longer time, or by combining both
these arrangements.
The arrangement for decreasing the proportion of combustible gas in the charge
is shewn at Figs. 2 and 3. The sleeve h carrying the cam n for the discharge
valve a (shewn in front view at Fig. 4) is fixed on the counter-shafts, but the
sleeve carrying the cam n' (shewn in front view at Fig. 5) that actuates the gas
valve 9 can slide longitudinally on the shaft, and is connected to a centrifugal
governor r.
it
The cam n¹ is formed with an incline on its rear side, so that according as it is
moved into different positions, relatively to the valve lever 21 by the governor,
effects the opening of the valve g for a longer or shorter time during the charging
period, and thus varies the proportion of combustible gas passing to the mixing
inlet valve e, which is of known construction. The charge is ignited either by an
electrical igniting device as shewn or by any other known igniting device.
It will be evident that in place of combustible gas, oil vapour or spray may be
used for working the engine, in which case any of the known arrangements for
introducing charges of such oil vapour or spray together with air into the cylinder
may be employed.
According to another modification, the above mode of operating is modified by only
admitting atmospheric air during the last part of the outstroke of the piston instead

page_text: of a combustible mixture of air and gas, while during the first part of the return
stroke a portion of the cylinder charge, which consists of a mixture of air and
combustion gases, is expelled through the discharge valve, after which the discharge
valve being closed the remainder of such charge is compressed while at the same time
combustible gas or petroleum vapour or spray is forced into the cylinder under
pressure so as to constitute together with the air in the cylinder the combustible
charge, which ignited when the piston arrives at the dead centre.
By this mode of working, any premature ignition of the charge such as may
occur in the mode of working herein before described by contact of the combustible
gases with the hot walls of the cylinder, or with the hot combustion gases, is
prevented, and in addition, the above described mode of forming the combustible.
charge allows of a more ready regulation of the engine, as the duration of the
compression period which in the said other arrangement is of fixed duration can in
this case be varied. By this means also, the degree of expansion and the quantity
of the combustible charge introduced can be varied to a greater extent.
Sheet 11. Fig. 1 shews a longitudinal section of a modified construction, Fig. 2 a
side view, Fig. 3 an end view, Figs. 4 and 5 are front views of the cams and
Figs. 6 to 8 are diagrams of different modes of operating. A is the cylinder, B the
piston C the crank shaft, a the discharge valve, a check valve in the discharge
passage, is an air admission valve, 9 is the valve device for controlling the
admission of gas or oil vapour or spray under pressure from a reservoir R into which
it may be forced by a pump worked by the engine, or otherwise; s is the counter-
shaft driven by mitre wheels D from the crank shaft, so as to revolve at the same
speed therewith.
In the diagram of the action shewn at Fig. 6 I represents the dead centre at end of
instroke, at which the compressed combustible charge is ignited. During the motion
from I to II the highly heated combustion gases expand and propel the piston, which
imparts a corresponding momentum to the fly wheel that enables the further move-
ments of the piston to be effected. At point II the discharge valve a is opened for
a short time, say during the travel from II to III, thereby enabling a portion of
the combustion gases to escape until that portion remaining in the cylinder is at or
about atmospheric pressure, whereupon the discharge valve is closed again, and on
the continued motion of the piston air is drawn into the cylinder for the remainder
of the stroke, from III to IV, which air mixes with the combustion gases still
remaining in the cylinder. On passing the dead centre at IV the piston, during the
first part of the return stroke, from IV to V is made to drive out a portion of the
mixture of air and combustion gases, the discharge valve being again opened for a
certain time for this purpose.
The remaining portion of the cylinder charge is then compressed during the
travel from V to 1, and during such compression the gas inlet valve is opened so as
to admit gas-under pressure into the cylinder for forming the combustible charge.
The explosive mixture formed by the mixture of the conibustible gas with the air
in the cylinder is then ignited at the dead centre at I, and the above cycle of
operations is repeated.
The points II, III and V may be determined at will, and it is to be understood
that the engine may also be arranged to work without the discharge of a portion of
the cylinder charge, consequently without again opening the discharge valve during
the period IV to V, as shewn by the diagram Fig. 7. In this case the arrangement
differs from that first described in that only air is drawn in during the suction part
of the outstroke, instead of combustible mixture, and that the charge of combustible
gas is introduced under pressure into the cylinder during the compression stroke.
A further modification of the mode of working can be effected by suppressing
entirely the opening of the discharge valve at the point II of the outstroke, the
combustible charge being in that case so proportioned that by the time the piston
shall have reached the point II, the combustion gases will have been expanded and
cooled down to such an extent as to have their pressure reduced to that of the
atmosphere, so that on the further motion of the piston an exhaust will at once be

page_text: produced, causing the air to be drawn in through valve l. In this case of course,
the discharge valve a must be opened during the first part of the instroke, as first
described, in order to discharge a greater or less proportion of the combustion
gases. With this arrangement therefore the diagram of action would be as shewn at
Fig. 8 the expansion of the combustion gases taking place during to II, the
introduction of air during II to IV, the expulsion of air and combustion gas mixture
during IV to V, and the compression of the charge and introduction of combustible
gas under pressure during V to I.
The actuation of the valves and regulation of the speed of the engine may, as
before stated, be effected in various known ways; Figs. 2 and 3 shew by way of
driven
example a side and end view of an arrangement in which a countershaft 8,
by mitre gear D at the same speed as the engine shaft, carries a fixed sleeve h on
which are two cams n and n² formed as shewn more clearly in the separate view at
Fig. 5, which cams act upon the roller of the lever Z which actuates the discharge
valve a, the cam n being made to open the discharge valve during the period II-III
Fig. 6, while the cam n² opens it during the period IV-V. The shaft s also
carries a sliding sleeve with cam n' which acts upon the roller o¹ on an arm of
the gas admission slide g.
The cam is shewn separately at Fig. 4.
The sleeve is connected to the
sleeve of the centrifugal governor » which is driven by bevil gearing from the
shafts, and which, when the engine is running too fast, is made to move the sleeve h¹
and cam n to the right to such an extent that the cam fails to act upon the roller o¹,
so that no charge of combustible gas is admitted to the cylinder, until the speed of
the engine is reduced to the normal again.
When the engine is intended to work according to the diagram Fig. 7 the cam n²
is dispensed with, and when it is to work according to diagram Fig. 8, the cam n is
dispensed with, and only n² is used.
As before stated, the combustible fluid employed may either be gas or oil vapour
or spray under pressure produced and stored in any known manner and the ignition
may either be effected by an electrical device or by any other known means.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:―
1. A two-stroke-cycle gas or oil motor engine wherein the discharge valve and
the gas or oil supply valves are operated by cams in such manner as to cause the
discharge valve to be opened for a short time when the piston has arrived at
fractional part of its outstroke, in order to allow the combustion gases to escape,
after which the discharge valve is closed and the gas or oil valve is opened during
the remainder of the outstroke, so as to introduce a combustible charge of gas or
oil vapour or spray and air into the cylinder during such time, which charge is
then compressed by the instroke of the piston, and is then ignited substantially as
described with reference to Figs. 1 to 6 on Sheet I of the drawings.
2. In a two cycle gas or oil motor engine, the combination with the cylinder A,
piston B and crankshaft C, of a countershafts driven at the same speed as the
crank shaft, a cam n fixed on the said shaft and made to open the discharge valve a
of the cylinder by means of a lever Z during a short period of the outstroke, and a
cam n' on the shaft s serving to open the gas or oil supply valve 9 after the closing
of the discharge valve, in order to admit a combustible charge into the cylinder
through a mixing valve e during the remainder of the outstroke of the piston, such
charge being compressed by the instroke of the piston and then fired by an igniting
device, substantially as described with reference to Figs. 1 to 6 on Sheet 1 of the
drawings.
3. A two stroke cycle gas or oil motor engine having a discharge valve for the
escape of the combustion gases, a valve for the admission of air into the cylinder
and a valve or slide for admitting gas or oil vapour or spray under pressure into the
cylinder, the said discharge and gas or oil admission valves being actuated by cams

page_text: so as to to cause the discharge valve to be opened for a short time when the piston
has arrived at a fractional part of its outstroke in order to allow the combustion
gases to escape, after which the discharge valve is closed and the air valve opens to
admit air during the remainder of the outstroke, while during the return stroke the
cylinder charge is compressed and the gas or oil admission device is at the same
time opened to admit gas or oil vapour or spray under pressure for forming the
combustible charge, substantially as described, with reference to Figs. 1 to 6 on
Sheet II of the drawings.
4. In a two stroke cycle gas or oil motor engine, the combination with the
cylinder A, piston B and crankshaft C of a countershaft s driven at the same speed
as the crankshaft, cams n² fixed on the said shaft and formed so as to open the
discharge valve a of the cylinder by means of a lever Z firstly during a short period
of the outstroke, and secondly during a portion of the instroke a cam n' on shaft s
serving to open the valve or slide 9 for admission of gas or oil vapour or spray
under pressure during the instroke of the piston, and an air inlet valve for
admitting air into the cylinder during the end portion of the outstroke, substan-
tially as described with reference to Figs. 1 to 6 on Sheet II of the drawings.
5. The herein described modified arrangement of the construction referred to in
the preceding claim whereby the engine is made to operate according to the
diagram at Fig. 7 Sheet II.
6. The herein described modified arrangement of the construction referred to in
Claim 4 whereby the engine is made to operate according to the diagram at Fig. 8
Sheet II.
Dated this 15th day of March 1893
ABEL & IMRAY,
Agents for the Applicant.