Improvements in Gas Engines.
Year: 1886

page_text: Date of Application, 12th Mar., 1886.
Complete Left, 11th Dec., 1886.
Complete Accepted, 11th Jan., 1887.
Improvements in Gas Engines.
1, JAMES ATKINSON, of 3 Nassington Road, Hampstead, London, N.W Engineer do
hereby declare the nature of my invention for IMPROVEMENTS IN GAS ENGINES to
be as follows
Gas Engines constructed in accordance with the Letters Patent No. 2712, A.D. 1885.
there are
granted to me have in actual practice proved to be economical and simple;
however some conditions of working in which such a type of engine might not be the
most suitable form, and my present invention is for the purpose of getting similar
results, with a different construction of engine.
On referring to the above mentioned Letters Patent, it will be found that I attached
very great importance to the fact that the engine developed the power in a short space
of time, and carried the expansion of the compressed charge, after ignition, to more
than the original volume; owing to these advantages I have been enabled to develop a
horse-power for I believe less gas than has been done in any previous construction of
engine. It will be seen that in this invention I retain these proved advantages.
I construct my improved engine in the following manner :-
I employ (say) a vertical single-acting cylinder open at the top and fitted with a
trunk piston, at a point above this cylinder there is a fixed centre-pin, hereinafter called
the centre-pin, on this fixed centre-pin a short link (or links), hereinafter called the
vibrating link is connected so that its lower end can swing or vibrate radially about the
fixed centre-pin, this lower end is connected by means of a longer link (or links), here-
inafter called the piston link, to the piston. At the junction of the vibrating link with
the piston link, the small end of the connecting rod is attached, the other end being
connected to the crank-pin. A line drawn through the centre of the main shaft round
which the crank pin revolves and the bottom end of the vibrating link forms a right-
angle, or an angle almost a right-angle, with the centre line of the cylinder.
It will be seen from this description that if the centre-pin is in the axial line of the
cylinder, and the connecting rod causes the vibrating link to swing to the same
distance on each side of the axial line of the cylinder, the piston will perform two
up and two down strokes in the cylinder for each revolution of the main shaft,
corresponding with about each quarter revolution of the main shaft; one quarter

page_text: revolution being employed by drawing in the explosive mixture, the next one in
compressing it, the third one in transmitting the power from the ignited charge, and the
last quarter revolution expels the exhaust. Also it will be seen that these strokes
would all be of equal length, and the expansion of the ignited charge would only be
carried to original volume; to enable the expansion to be carried to more than
original volume the drawing in and compressing strokes require to be made shorter
than the expansion and exhaust strokes. To do this I shift the main shaft centre
nearer to or farther from the axial line, also I may shift the centre-pin out of the
axial line, thus making these strokes unequal and obtaining the desired result.
I prefer to allow the piston to draw the explosive mixture in through a self-acting
valve, the gas being controlled by a governor valve, the exhaust valve may be
worked by an eccentric or cam on the main shaft. The ignition being caused by
means of the red hot tube described in previous Letters Patent, and timed by means
of a small slide worked by an eccentric or cam on the main shaft. In some instances
the slide causing the ignition might also regulate the admission.
With some kinds of gas it may be desirable to .expel the residuum left from a
previous ignition; to do this it is necessary to cause the piston to descend lower
when completing the exhausting stroke than when completing the compressing stroke
and this can be done in the following manner :-
at
The small end of the connecting rod is replaced with a end, the upper end of
the being connected to the vibrating link, and the lower end of the to the
piston link, the main shaft centre being raised or lowered so that when the exhausting
stroke is completed the vibrating link, the end of the connecting rod, and the
piston link are more in a straight line with each other than they are when
completing the compressing stroke, thus causing the piston to work close to the end of
the cylinder when exhausting, and not so low when compressing, so as to leave
space for the compressed mixture.
It will be seen that the whole cycle of operations is performed in one revolution
of the main shaft, and a working stroke made every revolution.
The cylinder may be placed horizontally or inclined, also two or more cylinders
may be arranged so as to form a coupled engine. The cylinder might be made
double-acting:
The combination of the links, the connecting rod, and the position of the working.
centres may be modified to suit varying circumstances; the object being to get the
peculiar piston movement by means of the toggle formed by the links & rod.

page_text: I, JAMES ATKINSON, of 3 Nassington Road, Hampstead, London. N.W. Engineer,
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 ascer-
tained in and by the following statement:-
The Gas Engines constructed in accordance with the Letters Patent No. 2712
A.D. 1885, granted to me; have in actual practice proved to be economical and
reliable;
there are however some conditions of working under which they might not
be the most suitable form. This invention is for the purpose of getting similar
results by means of a different construction of engine.
On referring to the Letters Patent No. 2712 A.D: 1885, it will be seen that the
power was developed in a very short space of time, and the expansion of the ignited
compressed charge was continued to a greater volume than the original volume
before compression, this extra expansion taking place in the same cylinder. (In
actual practice twice the original volume has been found to give good results).
Owing to these proved advantages, which are retained in this invention, I have
been enabled to construct gas engines which have consumed less gas per effectual
horse-power, than, so far as I know, is possible with any gas engine which does not
embody them.
I construct my improved engine as described in this specificatiou, and substantially
as shown in the accompanying drawings, in which Figs. 1, 2, 3, and 4, sheet 1. are
diagrammatical views showing four positions of the moving parts of the engine,
corresponding to four positions of the crank pin. Fig. 5 Sheet 2, is a sectional
elevation. Fig. 6 Sheet 3, is an elevation. Fig. 7 Sheet 4, is a plan and figs. 8
and 9 Sheet 5, are separate views of details of the engine.
The engine has an inclined cylinder A, (or this cylinder may be placed horizontally
or vertically), formed by forcing a cylindrical liner into a portion of the main
framing of the engine, the space between this portion of the engine and the liner
forming a water jacket; the cylinder A is closed at its lower end by a cover, in
which passages for the inlet of gas and air, and outlet for the exhaust are formed;
the other end is left open, and a single acting piston B is fitted. The piston is
connected by a link (or links) C (hereinafter called the piston link) to a pin D,
which is fixed in the connecting rod E, being attached to the crank F; the upper
end of the rod E is fitted with another pin G, forming a T head to it; to the pin G,
one end of the links (or link) N, is attached the other ends (or end) being connected
to a fixed centre I (hereinafter called the centre pin; the links N which vibrate
round the centre pin I being called the vibrating links).
From an examination of Figs. 1, 2, 3, and 4 Sheet 1, it will be seen that the
piston B has a peculiar motion imparted to it by the revolution of the crank pin F,
and this peculiar motion enables the whole cycle of operations necessary to a com-
pression gas engine to be performed by one piston in a single acting cylinder for

page_text: each revolution of the crank that is to say, the gas and air are drawn in, com-
pressed, ignited, expanded doing the work, and expelled once per revolution.
Fig. 1. Sheet 1, shows the position of the crank F, the various rods, and the piston
at the end of the exhausting stroke, and whilst in this position the piston may be
worked as close to the cover as is consistant with safety, so that the residuum may
be thoroughly expelled if desired. As the crank F revolves in the direction shown
by the arrow, the piston B is moved into the position shown in Fig. 2, during this
movement the gas and air forming an intermittent, homogeneous, explosive mixture,
are drawn into the cylinder A. The crank F continuing to revolve moves the
piston B back so as to compress the charge until the position shown in Fig. 3 is
reached, when the charge is ready for ignition, after which the increased pressure
due to ignition drives the piston B into the position shown in Fig. 4, thus imparting
power to the crank shaft F; the stored up energy carrying the crank shaft round
during the rest of the revolution, the exhaust being driven out whilst the engine is
passing from the position shown in Fig. 4, to that shown in Fig. 1.
The relative proportions of the capacities in the cylinder A. when in the positions
shown in Fig. 1 and 3 may be varied by altering the distance apart of the pins D and G,
or their relative position to the crank pin, and also, partly, by the position of the main
shaft centre R: If these pins D and G coincide, these capacities will be the same and
it will be seen that in that case residium will be left in the end of the cylinder A at
the termination of the exhaust stroke, and this residuum will be left in the cylinder and
form part of its contents when the next working stroke is made. The further apart
the pins D and G are, and also more or less influenced by the relative positions of the
pins D and G in relation to the crank pin end of the connecting rod E, and also by the
position of the main shaft centre R, more or less of the residuum may be expelled, and
by causing the piston B to work close to the end of the cylinder A when completing
the exhausting stroke, (the engine then being in the position shown in Fig. 1. Sheet 1.)
practically the whole of the residuum is expelled and the engine will be caused to
work with a completely fresh charge for each ignition. To obtain the best position
for the pins D and G it is necessary that they should be more or less in a straight
line with the piston link and the vibrating links N when in the position shown in
Fig. 1. Sheet 1. and not in a straight line when in the position shown in Fig. 3.
Sheet 1.
It is not necessary that the centre pin I should be in the axial line of the cylinder
A, and I prefer to put it a little on one side.
The relative proportions of the capacities in the cylinder A, when in the positions
shown in Fig. 2, and 4, define the amount of the expansion, these proportions are
varied chiefly by moving the crank shaft centre R nearer to, or further away from
the axial line of the cylinder A, or by lengthening or shortening the connecting
rod E as hereinbefore stated a satisfactory amount of expansion is to double the
original volume of the charge previously to its being compressed, if however a greater
amount of power should be desired from the same capacity of the cylinder, a less ratio
of expansion may be given, though this might be at the sacrifice of some of the economy.
So far as I can judge from the experience I have had with the engines constructed
in accordance with Letters Patent No. 2712. A.D. 1885, the greatest amount of economy
will be obtained by so arranging the expansion as to have a terminal pressure of about
12 to 15 lbs. above the atmosphere; this will probably require an expansion of nearly
twice the original volume in a small engine, and over twice the original volume in a
larger engine.
."
This engine can be so arranged that it will run in either direction, as started; to do
this it would be advisable to make the pins D and G coincide, also if any valves are
moved by cams, or eccentrics, they might be loose on the shaft, and moved by snugs
or catches fixed in the proper position; as is commonly done with reversing steam
engines.
+
If the centre pin I is placed on the axial line, the centres D and G made to coincide,
and the crank shaft centre R. together with the length of the connecting rod E so
arranged that the centres D and. G vibrate to one equal distance on either side of the

page_text: axial line, an engine could be constructed to give two working strokes for each revo-
lution with one single-acting working cylinder, provided that a separate single-acting
pump having its piston driven in a similar manner, or an ordinary double-acting pump
arranged so as to deliver a compressed explosive charge into the working cylinder at
the proper time.
The necessary valves for the admission of gas and air, for governing the engine, for
causing the ignition, and for letting out the exhaust may be variously arranged to suit
the conditions of working. I show a suitable arrangement of these valves in connection
with an engine embodying these improvements on Sheets 2, 3, 4 and 5, of the accom-
panying drawings.
In this engine the exhaust valve K is of a form very commonly used for this purpose
and is shown worked by an eccentric through a wayshaft and levers; a simple non-
return valve L is placed in the exhaust pipe which prevents any of the exhaust being
drawn back into the cylinder when the governor valve operates to prevent the admission
of a full working charge into the cylinder, as will be hereinafter described.
The admission and governor valve is shown in Fig. 8, Sheet 5, and is similar to that
described by me and illustrated in previous Letters Patent. It operates so as to
regulate the amount of charge required to be drawn in to keep the engine up to the
speed desired, and to which the governor spring P is adjusted, the governor (and
suction) valve H closing onto the lower seating and preventing a full charge being
drawn in if the engine exceeds the speed to which the spring P. is adjusted and this
takes place earlier or later during the suction stroke as is determined by the resistance
of the entering gas and air on the valve H, and the strength of the spring P. The amount
of charge drawn in determines the power given out during the next working stroke.
If preferred an ordinary governor cutting off the supply of gas may be used.
The ignition arrangement shown in Fig. 9. Sheet 5, consists of a tube Y, kept red
hot by an external flame, and the timing of the ignition is decided by a small slide Q,
which places the tube in communication with the cylinder at the proper time, and also
contains a small groove for ventilating the tube Y. This arrangement of igniting has
been described by me in previous Letters Patent; also with care the slide can be
dispensed with and the igniting tube left always in free communication with the
cylinder, as described by me in Letters Patent No. 16404 A.D. 1884. If the tube is
used without a slide it would be desirable to govern the engine by some other means
than that shown in Fig. 8. Sheet 5, owing to the unequal pressures to which the charge
is compressed when this valve is used, which would cause too great an irregularity in
the times of the ignitions. The ignition may be caused by means of a slide with an
external flame, by electricity, or any other known means. Also one slide may be used
for the ignition and admission as is very commonly done.
The working gear may be arranged in any suitable manner, the essential requirement
being to obtain the peculiar piston movement which consists of four strokes for cach
revolution of the crank shaft F; one of these strokes being used for drawing in the
charge, one for compressing the charge, one for imparting power to the engine during
the expansion of the ignited charge, and the other for expelling the exhaust; the
lengths of these strokes and the points at which they commence and end, being under
control, as hereinbefore set forth. The cylinder being placed in any desired position
in relation to the necessary rods, levers, and working centres, as may be most con-
venient and suitable. Also more than one cylinder may be used to form a combined
engine, or the separate pump above mentioned may be combined with a cylinder whose
piston by means of the motion described gives two working strokes per revolution, the
other two strokes being exhausting strokes the charges being drawn in & compressed
in the pump.
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. Compression Gas-engines constructed generally and substantially as described
and illustrated in the accompanying specification and drawings.

page_text: .. 2. In a compression gas-engine a single-acting piston working in a single-acting
cylinder in such a manner that two outward and two inward strokes are made for one
revolution of the crank shaft to which the piston is connected, of such a character as to
enable this piston to perform all the operations necessary to the completion of the cycle
during each revolution.
3. In a compression gas-engine the peculiar arrangement of the rods C. N. and E.
with their connection to the crank shaft F, giving the special and regulated motions to
the piston A, substantially as described and illustrated in the accompanying
specification.

page_text: Date of Application, 12th Mar., 1886.
Complete Left, 11th Dec., 1886.
Complete Accepted, 11th Jan., 1887.
I, JAMES ATKINSON, of 3 Nassington Road, Hampstead, London, N.W. Engineer do
hereby declare the nature of my invention for IMPROVEMENTS IN GAS ENGINES to
be as follows:-
-
Gas Engines constructed in accordance with the Letters Patent No. 2712, A.D. 1885.
granted to me have in actual practice proved to be economical and simple; there are
however some conditions of working in which such a type of engine might not be the
inost suitable form, and my present invention is for the purpose of getting similar
results, with a different construction of engine.
On referring to the above mentioned Letters Patent, it will be found that I attached
very great importance to the fact that the engine developed the power in a short space
of time, and carried the expansion of the compressed charge, after ignition, to more
than the original volume; owing to these advantages I have been enabled to develop a
horse-power for I believe less gas than has been done in any previous construction of
engine. It will be seen that in this invention I retain these proved advantages.
I construct my improved engine in the following manner :-
I employ (say) a vertical single-acting cylinder open at the top and fitted with a
trunk piston, at a point above this cylinder there is a fixed centre-pin, hereinafter called
the centre-pin, on this fixed centre-pin a short link (or links), hereinafter called the
vibrating link is connected so that its lower end can swing or vibrate radially about the
fixed centre-pin, this lower end is connected by means of a longer link (or links), here-
inafter called the piston link, to the piston. At the junction of the vibrating link with
the piston link, the small end of the connecting rod is attached, the other end being
connected to the crank-pin. A line drawn through the centre of the main shaft round
which the crank pin revolves and the bottom end of the vibrating link forms a right-
angle, or an angle almost a right-angle, with the centre line of the cylinder.
It will be seen from this description that if the centre-pin is in the axial line of the
cylinder, and the connecting rod causes the vibrating link to swing to the same
distance on each side of the axial line of the cylinder, the piston will perform two
up and two down strokes in the cylinder for each revolution of the main shaft,
corresponding with about each quarter revolution of the main shaft; one quarter

page_text: revolution being employed by drawing in the explosive mixture, the next one in
compressing it, the third one in transmitting the power from the ignited charge, and the
last quarter revolution expels the exhaust. Also it will be seen that these strokes
would all be of equal length, and the expansion of the ignited charge would only be
carried to original volume; to enable the expansion to be carried to more than
original volume the drawing in and compressing strokes require to be made shorter
than the expansion and exhaust strokes. To do this I shift the main shaft centre
nearer to or farther from the axial line, also I may shift the centre-pin out of the
axial line, thus making these strokes unequal and obtaining the desired result.
I prefer to allow the piston to draw the explosive mixture in through a self-acting
valve, the gas being controlled by a governor valve, the exhaust valve may be
worked by an eccentric or cam on the main shaft. The ignition being caused by
means of the red hot tube described in previous Letters Patent, and timed by means
of a small slide worked by an eccentric or cam on the main shaft. In some instances
the slide causing the ignition might also regulate the admission.
With some kinds of gas it may be desirable to expel the residuum left from a
previous ignition; to do this it is necessary to cause the piston to descend lower
when completing the exhausting stroke than when completing the compressing stroke
and this can be done in the following manner :-
T
The small end of the connecting rod is replaced with a end, the upper end of
the being connected to the vibrating link, and the lower end of the to the
piston link, the main shaft centre being raised or lowered so that when the exhausting
stroke is completed the vibrating link, the end of the connecting rod, and the
piston link are more in a straight line with each other than they are when
completing the compressing stroke, thus causing the piston to work close to the end of
the cylinder when exhausting, and not so low when compressing, so as to leave
space for the compressed mixture.
It will be seen that the whole cycle of operations is performed in one revolution
of the main shaft, and a working stroke made every revolution.
The cylinder may be placed horizontally or inclined, also two or more cylinders
may be arranged so as to form a coupled engine. The cylinder might be made
double-acting.
The combination of the links, the connecting rod, and the position of the working
centres may be modified to suit varying circumstances; the object being to get the
peculiar piston movement by means of the toggle formed by the links & rod.

page_text: Improvements in Gas Engines.
I, JAMES ATKINSON, of 3 Nassington Road, Hampstead, London. N.W. Engineer,
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 ascer-
tained in and by the following statement:-
The Gas Engines constructed in accordance with the Letters Patent No. 2712
A.D. 1885, granted to me; have in actual practice proved to be economical and
reliable; there are however some conditions of working under which they might not
be the most suitable form. This invention is for the purpose of getting similar
results by means of a different construction of engine.
On referring to the Letters Patent No. 2712 A.D. 1885, it will be seen that the
power was developed in a very short space of time, and the expansion of the ignited
compressed charge was continued to a greater volume than the original volume
before compression, this extra expansion taking place in the same cylinder. (In
actual practice twice the original volume has been found to give good results).
Owing to these proved advantages, which are retained in this invention, I have
been enabled to construct gas engines which have consumed less gas per effectual
horse-power, than, so far as I know, is possible with any gas engine which does not
embody them.
I construct my improved engine as described in this specification, and substantially
as shown in the accompanying drawings, in which Figs. 1, 2, 3, and 4, sheet 1. are
diagrammatical views showing four positions of the moving parts of the engine,
corresponding to four positions of the crank pin. Fig. 5 Sheet 2, is a sectional
elevation. Fig. 6 Sheet 3, is an elevation. Fig. 7 Sheet 4, is a plan and figs. 8
and 9 Sheet 5, are separate views of details of the engine.
The engine has an inclined cylinder A, (or this cylinder may be placed horizontally
or vertically), formed by forcing a cylindrical liner into a portion of the main
framing of the engine, the space between this portion of the engine and the liner
formning a water jacket; the cylinder A is closed at its lower end by a cover, in
which passages for the inlet of gas and air, and outlet for the exhaust are formed;
the other end is left open, and a single acting piston B is fitted. The piston is
connected by a link (or links) C (hereinafter called the piston link) to a pin D,
which is fixed in the connecting rod E, being attached to the crank F; the upper
end of the rod E is fitted with another pin G, forming a T head to it; to the pin G,
one end of the links (or link) N, is attached the other ends (or end) being connected
to a fixed centre I (hereinafter called the centre pin; the links N which vibrate
round the centre pin I being called the vibrating links).
From an examination of Figs. 1, 2, 3, and 4 Sheet 1, it will be seen that the
piston B has a peculiar motion imparted to it by the revolution of the crank pin F,
and this peculiar motion enables the whole cycle of operations necessary to a com-
pression gas engine to be performed by one piston in a single acting cylinder for

page_text: each revolution of the crank :-that is to say, the gas and air are drawn in, com-
pressed, ignited, expanded doing the work, and expelled once per revolution.
Fig. 1. Sheet 1, shows the position of the crank F, the various rods, and the piston
at the end of the exhausting stroke, and whilst in this position the piston may be
worked as close to the cover as is consistant with safety, so that the residuum may
be thoroughly expelled if desired. As the crank F revolves in the direction shown
by the arrow, the piston B is moved into the position shown in Fig. 2, during this
movement the gas and air forming an intermittent, homogeneous, explosive mixture,
are drawn into the cylinder A. The crank F continuing to revolve moves the
piston B back so as to compress the charge until the position shown in Fig. 3 is
reached, when the charge is ready for ignition, after which the increased pressure
due to ignition drives the piston B into the position shown in Fig. 4, thus imparting
power to the crank shaft F; the stored up energy carrying the crank shaft round
during the rest of the revolution, the exhaust being driven out whilst the engine is
passing from the position shown in Fig. 4, to that shown in Fig. 1.
The relative proportions of the capacities in the cylinder A when in the positions
shown in Fig. 1 and 3 may be varied by altering the distance apart of the pins D and G,
or their relative position to the crank pin, and also, partly, by the position of the main
shaft centre R. If these pins D and Ġ coincide, these capacities will be the same and
it will be seen that in that case residium will be left in the end of the cylinder A at
the termination of the exhaust stroke, and this residuum will be left in the cylinder and
form part of its contents when the next working stroke is made. The further apart
the pins D and G are, and also more or less influenced by the relative positions of the
pins D and G in relation to the crank pin end of the connecting rod E, and also by the
position of the main shaft centre R, more or less of the residuum may be expelled, and
by causing the piston B to work close to the end of the cylinder A when completing
the exhausting stroke, (the engine then being in the position shown in Fig. 1. Sheet 1.)
practically the whole of the residuum is expelled and the engine will be caused to
work with a completely fresh charge for each ignition. To obtain the best position
for the pins D and G it is necessary that they should be more or less in a straight
line with the piston link C and the vibrating links N when in the position shown in
Fig. 1. Sheet 1. and not in a straight line when in the position shown in Fig. 3.
Sheet 1.
It is not necessary that the centre pin I should be in the axial line of the cylinder
A, and I prefer to put it a little on one side.
The relative proportions of the capacities in the cylinder A, when in the positions
shown in Fig. 2, and 4, define the amount of the expansion, these proportions are
varied chiefly by moving the crank shaft centre R nearer to, or further away from
the axial line of the cylinder A, or by lengthening or shortening the connecting
rod E; as hereinbefore stated a satisfactory amount of expansion is to double the
original volume of the charge previously to its being compressed, if however a greater
amount of power should be desired from the same capacity of the cylinder, a less ratio
of expansion may be given, though this might be at the sacrifice of some of the economy.
So far as I can judge from the experience I have had with the engines constructed
in accordance with Letters Patent No. 2712. A.D. 1885, the greatest amount of economy
will be obtained by so arranging the expansion as to have a terminal pressure of about
12 to 15 lbs. above the atmosphere; this will probably require an expansion of nearly
twice the original volume in a small engine, and over twice the original volume in a
larger engine.
This engine can be so arranged that it will run in either direction, as started; to do
this it would be advisable to make the pins D and G coincide, also if any valves are
moved by cams, or eccentrics, they might be loose on the shaft, and moved by snugs
or catches fixed in the proper position; as is commonly done with reversing steam
engines.
If the centre pin I is placed on the axial line, the centres D and G made to coincide,
and the crank shaft centre R together with the length of the connecting rod E so
arranged that the centres D and. G vibrate to one equal distance on either side of the

page_text: axial line, an engine could be constructed to give two working strokes for each revo-
lution with one single-acting working cylinder, provided that a separate single-acting
pump having its piston driven in a similar manner, or an ordinary double-acting pump
arranged so as to deliver a compressed explosive charge into the working cylinder at
the proper time.
The necessary valves for the admission of gas and air, for governing the engine, for
causing the ignition, and for letting out the exhaust may be variously arranged to suit
the conditions of working. I show a suitable arrangement of these valves in connection
with an engine embodying these improvements on Sheets 2, 3, 4 and 5, of the accom-
panying drawings.
In this engine the exhaust valve K is of a form very commonly used for this purpose
and is shown worked by an eccentric through a wayshaft and levers; a simple non-
return valve L is placed in the exhaust pipe which prevents any of the exhaust being
drawn back into the cylinder when the governor valve operates to prevent the admission
of a full working charge into the cylinder, as will be hereinafter described.
The admission and governor valve is shown in Fig. 8, Sheet 5, and is similar to that
described by me and illustrated in previous Letters Patent. It operates so as to
regulate the amount of charge required to be drawn in to keep the engine up to the
speed desired, and to which the governor spring P is adjusted, the governor (and
suction) valve H closing onto the lower seating and preventing a full charge being
drawn in if the engine exceeds the speed to which the spring P. is adjusted and this
takes place earlier or later during the suction stroke as is determined by the resistance
of the entering gas and air on the valve H, and the strength of the spring P. The amount
of charge drawn in determines the power given out during the next working stroke.
If preferred an ordinary governor cutting off the supply of gas may be used.
The ignition arrangement shown in Fig. 9. Sheet 5, consists of a tube Y, kept red
hot by an external flame, and the timing of the ignition is decided by a small slide Q,
which places the tube in communication with the cylinder at the proper time, and also
contains a small groove for ventilating the tube Y. This arrangement of igniting has
been described by me in previous Letters Patent; also with care the slide can be
dispensed with and the igniting tube left always in free communication with the
cylinder, as described by me in Letters Patent No. 16404 A.D. 1884. If the tube is
used without a slide it would be desirable to govern the engine by some other means
than that shown in Fig. 8. Sheet 5, owing to the unequal pressures to which the charge
is compressed when this valve is used, which would cause too great an irregularity in
the times of the ignitions. The ignition may be caused by means of a slide with an
external flame, by electricity, or any other known means. Also one slide may be used
for the ignition and admission as is very commonly done.
The working gear may be arranged in any suitable manner, the essential requirement
being to obtain the peculiar piston movement which consists of four strokes for each
revolution of the crank shaft F; one of these strokes being used for drawing in the
charge, one for compressing the charge, one for imparting power to the engine during
the expansion of the ignited charge, and the other for expelling the exhaust; the
lengths of these strokes and the points at which they commence and end, being under
control, as hereinbefore set forth. The cylinder being placed in any desired position
in relation to the necessary rods, levers, and working centres, as may be most con-
venient and suitable. Also more than one cylinder may be used to form a combined
engine, or the separate pump above mentioned may be combined with a cylinder whose
piston by means of the motion described gives two working strokes per revolution, the
other two strokes being exhausting strokes; the charges being drawn in & compressed
in the pump.
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. Compression Gas-engines constructed generally and substantially as described
and illustrated in the accompanying specification and drawings.

page_text: 2. In a compression gas-engine a single-acting piston working in a single-acting
cylinder in such a manner that two outward and two inward strokes are made for one
revolution of the crank shaft to which the piston is connected, of such a character as to
enable this piston to perform all the operations necessary to the completion of the cycle
during each revolution.
3. In a compression gas engine the peculiar arrangement of the rods C. N. and E.
with their connection to the crank shaft F, giving the special and regulated motions to
the piston A, substantially as described and illustrated in the accompanying
specification