An Improved Gas Engine and Gas Generator therefor.
Year: 1889

page_text: Date of Application, 14th Feb., 1889
Complete Specification Left, 14th Nov., 1889-Accepted, 14th Dec., 1889
PROVISIONAL SPECIFICATION.
An Improved Gas Engine and Gas Generator therefor.
I, CEPHAS FRANÇOIS LEONCE GARDIE, of 23, Boulevard de Strasbourg, Paris,
in the republic of France, Engineer do hereby declare the nature of this inven-
tion to be as follows:-
The improved motor belongs to that class of motors in which motive power is
produced by the expansion of a gaseous mixture arising from the combustion,
without explosion, of inflammable gas and combustive air. In the Specification
of a Patent No. 6161 dated 6th May 1886 a motor is described based on this
principle. Since the date of this Patent numerous modifications and improve-
ments in the construction and operation of this motor have been devised and
form the subject of the present application. In order that the improvements
may be fully understood I will first describe the principle on which the same
are based.
The system comprises in principle the following combination.
The gas issuing from a special producer or generator passes into a compressor
and at the same time the air also passes through a compressor of special con-
struction. In consequence of this compression the gas and air become leated
to about 200° C. The gas and air thus compressed are further heated to
about 400° C. by passing separately into heat recuperators; the gas and air
then passes through dividers, which divide them into thin alternate layers, into
the motor cylinders in which the gaseous mixture burns on coming in contact
with an igniter. Owing to the combustion the temperature reaches 1500° C.,
the gases expand and drive the pistons in the cylinders. In consequence of the
expansion the temperature falls and the still heated residues which escape from
the cylinders are utilized in the recuperators to heat the gas and air which feed
the motor cylinders.
To
The gas for producing motive power by its combustion is obtained by the pas-
sage of a mixture of superheated air and steam over incandescent "fuel.
effect this I employ a boiler, a superheater and a gas generator; the latter is
constructed with a chamber lined with refractory bricks the lower part of which
is provided with a grate beneath which is an ash pit. The gas generator is
supplied with fuel through a door and in order to cause the cinders to fall the
fuel is stirred about with a bar or rake introduced through an opening ordinarily
closed by a plug. Sight holes closed by sheets of mica allow of the interior
being inspected.
The gas produced in the generator passes through a grate, and, a valve being
raised, it arrives above the firing grate of the boiler constructed of tubes arranged
between two tube plates. The boiler is provided with a water gauge and a feed
pipe connected with a small feed pump. The steam generated in this boiler
issues through a tube and passes into an injector; this injection of steam induces
a current of air which together with the steam which carries it along, enters
the super-heater constructed of tubes placed between two tube plates; on the
periphery of the cylindrical part of the super heater is arranged a corrugated
sheet metal plate allowing of expansion. The air and steam circulate round the
tubes of the super heater and in the space between the tube plates while the
tubes give passage to the heated gas which has already passed through the tubes
of the boiler. The manner in which this gas, already partially cooled, is utilized
is hereinafter described.
The mixture of air and steam superheated io about 300° C. contained in the
super-heater leaves at its lower part through a pipe and is conducted to the
unnar nart of the gas generator. This mixture then passes through the mass of

page_text: ignited fuel the air maintains the combustion and the steam becomes decom-
posed into its elementary gases which combine with the carbonized gases
resulting from the combustion.
The current of superheated air and steam is formed while descending into the
gas generator; the charge can therefore be effected (the door being open) without
any gas escaping, besides which the gas is obtained free from tar and smoke.
Safety valves are arranged above the gas generator and the superheater to
prevent excess of pressure; they open into pipes leading to a chimney.
The gas passing from the tubes of the superheater conducted into an arrange-
ment of two washers. The first washer through which the gas passes in descending
comprises an arrangement of perforated plates mounted on a central rod ter-
minating above in a ring whereby all the plates can be removed together. Water
from a perforated tube falls in a shower from plate to plate until it reaches a
lower tank or cistern provided with a partition the lower part of which dips into
the liquid. The gas which is washed and cooled by contact with the shower of
water is compelled to pass through the water in the cistern in order to reach the
second cylinder of the washer up which it rises in a cooled state and is then
ready to serve for the production of motive power.
The
gas passes from the washer to one of the compressors through a pipe. This
compressor is formed by the part of the motor-cylinder which is below the piston
the space above serving for the combustion of the gases and their expansion.
The said pipe opens into an admission valve which closes the entrance to a
passage opening into the cylinder beneath the piston. The said valve is operated
by a cam acting on a lever. Another valve under the action of a spring allows
of the passage of the compressed gas through a pipe to the gas recuperator where
it is heated to about 400° C. The motor comprises two cylinders which are
motor cylinders at their upper part, but the lower part of one of them serves
as a gas compressor and of the other as an atmospheric air compressor. From
these compressors the compressed gas or compressed air is conducted to the
respective recuperators.
The gas recuperator is constructed of an internal cylinder of sheet metal
provided at top and bottom with cast iron hemi-spherical covers between which
are arranged vertical tubes. The compressed gas enters and rises inside the
tubes and passes off by an upper tube. Heated gases which have escaped from
the motor cylinder after combustion circulate around the vertical tubes from top
to bottom.
The heat recuperator for the compressed air is constructed in the same manner.
From the gas recuperator the compressed gas passes through pipes to the
admission valves of the two motor cylinders. From the air recuperator the
compressed air passes through pipes to the admission valves of the iwo motor
cylinders.
The gas admission valve is separated from the air admission valve by a
partition. The spring rods of the said valves are operated by levers actuated by
cams. The escape of the burnt gases takes place through a valve the spring
rod of which is actuated by a cam.
Between the chambers of the gas and air admission valves and the internal
wall of the cylinder is a space in which the gas and air are divided into thin
alternate layers. This result is attained by means of a divider constructed of
parallel strips of steel which occupy the whole horizontal surface of the said
space but the openings between the strips alternately open into the gas valve box
and the air valve box. The gas and air thus reach the cylinders in thin superposed
suitably proportioned layers which are ignited on entering the cylinder. These layers
of gas and air pass through a passage formed in the end plane of the cylinder as
far as the igniter which is formed by a bulbous disc of platinum maintained
at red heat by a blow-pipe-flame from a spirit lamp. The passage through the
pipe from this lamp can be regulated by a screw and the said pipe is curved
and opens into a small nozzle from which issues the flame directed by a cylinder

page_text: of refractory material on to the platinum dise; air-holes are provided for feeding
the flame and also a chimney for the escape of the products of combustion.
The recuperators being, as above described, distinct from the cylinders it will
be obvious that I can also employ an arrangement in which a cylinder is employed,
the cover of which contains the recuperators. The gas arrives through the gas
inlet valve and passes into a compartment; the air arrives through its inlet valve
and passes into another compartment; tubes are provided for the passage of the
gas, and the air passes from its compartment into the cylinder through passages.
each stream of air enclosing a stream of gas. which produces as many inverted
jets of flame from the upper part of the cylinder. The escape of the gases from
the combustion is effected through a pipe which opens into a space in the upper
part of the end plane of the cylinder. The gases heat this space by circulating
therein and pass off through an exit valve. The mass of the end plane, being
thoroughly heated from above and below the compressed gas and air become
heated therein before entering the cylinder. This recuperator acts as a divider
the alternate layers of fluid hereinbefore described being replaced by concentric
streams.
The upper chamber of the cylinders in which the combustion of the gaseous
mixture takes place is provided on its inner periphery with thick segments of cast
iron separated from each other by a space of a few millimeters to allow of expan-
sion, and from the walls by sheets of asbestos against which they are firmly pressed
by bolts. When the gases enter and are burnt, these masses become heated and
store up the heat which they restore to the gases during the period of expansion.
The piston of each cylinder is formed of a body sufficiently thick to allow the
packing rings to be placed at a considerable distance from the heated interior of
the cylinder and sufficiently heavy to store up power during the most active
period of admission and combustion of the gases, which power is utilized towards
the end of the stroke (when the expansion is at the maximum) to overcome the
resistance of the pumps which is then at its highest. The piston is covered
with a plate which is secured thereto by bolts; sheet asbestos is interposed
between the plate and the piston.
To start the motor, heated gas from the superheater is passed into the cylinders
by means of a pipe provided with a valve, air being introduced. The escape of
the burnt gas takes place through a tube provided with a valve. In this manner
the preliminary heating of the combustion chambers of the motor cylinders is
effected.
The lubrication of the cylinders is effected in the part which serves as a
compression pump by means of mineral oil introduced drop by drop with the
gas or the air.
To facilitate the lubrication and insure the resistance of the
walls and decrease the work of compression of the gas and air I cause to circulate
in the double jacket of the cylinder, cold water from a pump this water being
subsequently utilised in the gas washers.
The piston rods actuate connecting rods which are attached to the crank shaft:
this shaft carries excentrics the rods of which actuate vertical rods which in
turn act on the studs of small cranks keyed on the three shafts of the valve
cams. By this means I obtain a rigid union between the cam of the cylinder
admission valve and that of the exhaust valve of the compression of the same
fluid, to preserve a constant pressure in the recuperators under any conditions.
The cams are constructed so as to effect the forward movement at one end
and the backward movement at the other end the cam surfaces being connected
by a gentle slope. To effect the distribution the cams are moved on their shafts
by means of arms which engage in grooves of the cams and are guided by
horizontal rods. These arms are operated simultaneously by a horizontal screw
which in order to start the apparatus working is onerated by means of a hand
wheel through hevil wheels and sour wheels. one of which spur wheels is keyed
on the screw. The two parts, right and left of the screw have their threads
running in opposite directions.
The arrangement is also provided with a governor operated by means of bevil

page_text: gearing. The clutch of this governor in rising or falling, according to the
distance apart of the governor balls, engages one of the hereinbefore described
bevil wheels and causes it to turn. The screw is actuated through the medium
of a bevil wheel the direction of rotation of which is determined by the before
mentioned bevil wheels according to which of them is in engagement with the
clutch the bevil wheel which effects the movement of the screw is keyed on
the axis of a worm which actuates a helicoidal wheel fixed on the screw.
distribution is regulated during working by the governor.
The
If equal volumes of gas and air were admitted to the cylinders the highest
temperature of combustion would be obtained and the products would have, after
expansion, a temperature of from 700° C. to 800° C. and would as they leave
injuriously affect the escape valves and the recuperators. In order to obtain a
lowering of temperature I slightly prolong the admission of air after the gas
admission valve has been closed: this is effected by forming the air admission
cam with a longer slope than that on the gas cam so that the air valve may be
raised for a somewhat longer time.
Under these conditions the burnt gases finally have a temperature of about
500° C. they pass from the cylinders to the recuperators through pipes.
Dil
1111
1000
G. F. REDFERN & Co..
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Gas Engine and Gas Generator therefor.
1, CEPHAS FRANÇOIS LEONCE GARDIE, of 2. Boulevard de Strasbourg, Paris,
in the republic of France, Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement:-
-
The improved motor belongs to that class of motors in which motive power is
produced by the expansion of a gaseous mixture arising from the combustion,
without explosion, of inflammable gas and combustive air. In the Specification
of a Patent No. 6161 dated 6th May 1886 a motor is described based on this
principle. Since the date of this Patent numerous modifications and improve-
ments in the construction and operation of this motor have been devised and
form the subject of the present application. In order that the improvements
may be fully understood I will first describe the principle on which the same
are based.
The system comprises in principle the following combination.
The gas issuing from a special producer or generator passes into a compressor
and at the same time the air also passes through a compressor of special con-
struction. In consequence of this compression the gas and air become heated
to about 200° C. The gas and air, thus compressed, are further heated to
about 400° C. by passing separately into heat recuperators: the gas and air
then passes through dividers, which divide them into thin alternate layers, into
the motor cylinders in which the gaseous mixture burns on coming in contact
with an igniter. Owing to the combustion the temperature reaches 1500° C..
the gases expand and drive the pistons in the cylinders. In consequence of the
expansion the temperature falls and the still heated residues which escape from
the cylinders are utilized in the recuperators to heat the gas and air which feed
the motor cylinder.
Such being the principle of my improved motor I will now proceed to describe
the same by reference to the accompanying drawing, in which―
Figure is a longitudinal elevation, partly in section, of a gas engine and
generator constructed according to my present improvements.
Figure 2 is a plan of figure 1.
Figure 3 is a side view of the mechanism one of the recuperators being shown
in vertical section.

page_text: Figure 4 is a transverse section on line XX of figure 2.
Figure 5 is a transverse section of the gas washer on line Y, Y of figure 2.
Figures 6 to 13 are views of some of the parts.
The gas for producing motive power by its combustion is obtained by the
passage of a mixture of superheated air and steam over incandescent fuel. To
effect this employ a boiler A, a superheater B and a gas generator C; the
latter is constructed with a chamber lined with refractory bricks, the lower
part of which is provided with a grate beneath which is an ash pit b. The gas
generator is supplied with fuel through a door e and in order to cause the cinders.
to fall the fuel is stirred about with a bar or rake introduced through an opening
ordinarily closed by a plug d. Sight holes g closed by sheets of mica allow of the
interior being inspected.
The gas produced in the generator C passes through a grate a and, a valve c
being raised, it arrives above the firing grate f of the boiler A constructed of tubes
arranged between two tube plates. The boiler is provided with a water gauge
and a feed pin n connected with a small feed pump E. The steam generated in
this boiler issues through a tube and passes at i into an injector: this injection
of steam induces a current of air which, together with the steam which carries it
along, enters the superheater B constructed of tubes placed between two tube
plates on the periphery of the cylindrical part of the super-heater is arranged a
corrugated sheet metal plate m allowing of expansion. The air and steam
circulate round the tubes of the superheater and in the space between the tube
plates, while the tubes give passage to the heated gas which has already passed
through the tubes of the boiler A. The manner in which this gas, already
partially cooled, is utilized is hereinafter described.
The mixture of air and steam superheated to about 300° C. contained in the
super-heater B leaves at its lower part through a pipe and is conducted to the
upper part of the gas generator Cat k. This mixture then passes through the
mass of ignited fuel: the air maintains the combustion and the steam becomes
decomposed into its elementary gases which combine with the carbonized gases
resulting from the combustion.
The current of super-heated air and steam is formed while descending into the
gas generator the charge can therefore be effected, (the door being open) without
any gas escaping, besides which the gas is obtained free from tar and smoke.
Safety valves 1, are arranged above the gas generator and the super-heater to
prevent excess of pressure: they open into pipes leading to a chimney D.
The gas passing from the tubes of the superheater is conducted into an arrange-
ment of two washers F. F. The first washer F through which the gas passes in
descending comprises an arrangement of perforated plates p figure 5, mounted on
a central rod q terminating above in a ring whereby all the plates can be removed
together. Water from a perforated tube falls in a shower from plate to plate
until it reaches a lower tank or cistern G provided with a partitions, the lower
part of which dips into the liquid. The gas which is washed and cooled by contact
with the shower of water is compelled to pass through the water in the cistern in
order to reach the second cylinder F of the washer up which it rises in a cooled
state and is then ready to serve for the production of motive power.
The gas passes from the washer to one of the compressors H through a pipe K.
This compressor is formed by the part of the motor cylinder which is below the
piston, the space above serving for the combustion of the gases and their ex-
pansion. This cylinder is shown in vertical section on an enlarged scale in
figure 6 the said pipe K opens into an admission valve u, which closes the en-
trance to a passage , opening into the cylinder beneath the piston S. The said
valve is operated by a cam I acting on a lever .. Another valve under the
action of a spring allows of the passage of the compressed gas through a pipet to
the gas recuperator J. where it is heated to about 400° C. The motor comprises
two cylinders, which are motor cylinders at their upper part but the lower part
of one of them serves as a gas compressor and of the other as an atmospheric air
compressor. From these compressors the compressed gas or compressed air is

page_text: conducted to the respective recuperators J or J₁, the gas passing through the
pipe to and the compressed air through the pipe to J.
The construction of the gas recuperator is clearly shown in section at figure 3:
it is constructed of an internal cylinder of sheet metal L, provided at top and
bottom with cast iron hemispherical covers between which are arranged vertical
tubes N. Tlie compressed gas enters at f and rises inside the tubes N and passes
off by an upper tubez. Heated gases which have escaped from the motor cylinder
after combustion circulate around the vertical tubes N from top to bottom, from
the tube a to the tube b¹,
The heat recuperator for the compressed air is constructed in the same manner;
it is shown at in figures 1 and 2.
io
From the gas recuperator the compressed gas passes through the pipes,
the admission valves of the two motor cylinders H H¹. In figure 6 the gas
admission valve for one cylinder is shown at c. From the air recuperator the
compressed air passes through the pipes, to the admission valves of the two
motor cylinders 'H, H. In figure 6 this air admission valve for one cylinder is in
front of the valve cl for the gas. By reference to figure 7 which is a section on the
line Z Z of Figure 6, it will be seen that the gas admission valve c is separated
from the air admission valve by a partition d. The spring rods of the said
valves and 2 are operated by levers e, 2 actuated by cams I I. The escape of
the burnt gases takes place through a valve f¹, the spring rod of which is actuated
by a cam I³.
:
Between the chambers of the gas and air admission valves c1, c2 and the internal
wall of the cylinder is a space in which the gas and air are divided into thin
alternate layers. This result is attained (figures 6 and 7) by means of a divider (
constructed of parallel strips of steel which occupy the whole horizontal surface
of the said space but the openings between the strips alternately open into the
gas valve box and the air valve box. This arrangement is shown in figure 8
which is a view taken on line 1-2 of figure 7. The gas and air thus reach the
cylinders in thin superposed suitably proportioned layers which are ignited on
entering the cylinder. These layers of gas and air pass through a passage g
(figure 6) formed in the end plane of the cylinder as far as the igniter which is
formed by a bulbous disc of platinum maintained at red heat by a blow-pipe-
flame from a spirit lamp P. The passage through the pipe from this lamp can
he regulated by a screw and the said pipe is curved and opens at j into a small
nozzle from which issues the flame directed by a cylinder of refractory material
onto the platinum disc '; P, 12 are air holes for feeding the flame and m¹ is a
chimney for the escape of the products of combustion.
The recuperators being as above described distinct from the cylinders it will be
obvious that I can also employ the arrangement of which figure 9 is a vertical
section and figure 10 a horizontal section on lines 3, 4 of figure 9; these figures
represent the upper part of a cylinder, the cover of which contains the recupera-
tors. The gas arrives through the gas inlet valve e and passes into a compart-
ment the air arrives through its inlet valve and passes into another com-
partment the tubes o are provided for the passage of the gas, and the air
passes from its compartment n² into the cylinder H through passages o², each
stream of air enclosing a stream of gas which produces as many inverted jets of
flame from the upper part of the cylinder. The escape of the gases from the com-
bustion is effected through a pipe pl which opens into a space Q in the upper part
of the end plane of the cylinder. The gases heat this space by circulating therein
and pass off at 72 through an exit valve. The mass of the end plane, being
thoroughly heated from above and below, the compressed gas and air become
heated therein before entering the cylinder. This recuperator acts as a divider
the alternate layers of fluid herein before described being replaced by concentric
streams.
The upper chamber of the cylinders in which the combustion of the gaseous
mixture takes place is provided on its inner periphery (see figure 6 and figure 11
which is a section on line 5, 5 of figure 6) with thick segments R of cast iron

page_text: separated from each other by a space of a few millimeters to allow of expansion,
and from the walls by sheets of asbestos against which they are firmly pressed by
bolis q'.
When the gases enter and are burnt, these masses become neated and
store up the heat which they restore to the gases during the period of expansion.
The piston of each cylinder is formed of a body S sufficiently thick to allow the
packing rings to be placed at a considerable distance from the heated interior
of the cylinder and sufficiently heavy to store up power during the most active
period of admission and combustion of the gases, which power is utilized towards
the end of the stroke (when the expansion is at the maximum) to overcome the
resistance of the pumps which is then at its highest. The piston is covered with
a plates, which is secured thereto by bolts &; sheet-asbestos is interposed
between the plate and the piston.
To start the motor heated gas from the superheater 1 is passed into the cylinders
by means of a pipe, (figures 1, 2, 3, 4) provided with a valve air being intro-
duced through (figure 2). The escape of the burnt gas takes place through a
tube (figures 3 to 6) provided with a valve u². In this manner the preliminary
heating of the combustion chambers of the motor cylinders is effected.
The lubrication of the cylinders is effected in the part which serves as a com-
pression pump by means of mineral oil introduced drop by drop with the gas r
the air. To facilitate the lubrication and to insure the resistance of the walls
and decrease the work of compression of the gas and air I cause to circulate in
the double jacket T (figures 1 and 6) of the cylinder, cold water from a pump U,
this water being subsequently utilized in the gas washers F, F.
The piston rods actuate connecting rods V, which are attached to the crank
shaft this shaft carries eccentrics, the rods Y of which actuate vertical
rods, which in turn act on the studs of small cranks e, e, keyed on the three
shafts of the valve cams 1, 11, 12, F. By this means I obtain a rigid union between
the cam of the cylinder admission valve and that of the exhaust valve of the
compressor of the same fluid, to preserve a constant pressure in the recuperators
under any conditions.
The cams, an end view of one of which is shown drawn to a large scale at
figure 12 and a. longitudinal section at figure 13, are constructed so as to effect
the forward movement at one end and the backward movement at the other end,
the cam surfaces being connected by a gentle slope. To effect the distribution
the cams are moved on their shafts, by means of arms, which engage in
grooves (figure 13) of the cams and are guided by the horizontal rods af,
(figures 1, 2 and 3). These arms are operated simultaneously by a horizontal
screw which in order to start the apparatus working is operated by means of a
hand wheel through bevil wheels c and d (figure 4) and spur wheels e, et, the
latter one of which spur wheels is keyed on the screw. The two parts, right
and left, of the screw 2 have their threads running in opposite directions.
The arrangement is also provided with a governor R operated by means of bevil
gearing The clutchy of this governor in rising or falling, according to
the distance apart of the governor balls, engages one of the herein before described
bevil wheels, g³ and causes it to turn. The screw is actuated through the
medium of a bevil wheel the direction of rotation of which is determined by the
before mentioned bevil wheels g, g³ according to which of them is in engage-
ment with the clutch y the bevil wheel which effects the movement of the
screw is keyed on the axis of a worm which actuates a helicoidal wheel
fixed on the screw a². The distribution is regulated during working by the
governor.
If equal volumes of gas and air were admitted to the cylinders the highest
temperature of combustion would be obtained and the products would have, after
expansion, a temperature of from 700° C. to 800° C. and would, as they leave,
injuriously affect the escape valves and the recuperators. Is order to obtain a
lowering of temperature I slightly prolong the admission of air after the gas
admission valve has been closed; this is effected by forming the air admission cam

page_text: with a longer slope than that on the gas cam, so that the air valve may be raised
for a somewhat longer time.
Under these conditions the burnt gases finally have a temperature of about
500° C. they pass from the cylinders to the recuperators through pipes q².
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is:
1. A thermal motor in which the motive force is produced by the combustion
followed by the expansion of a mixture of gas and air, the gas and air being
previously compressed, then heated by the exhaust products.
2. The production of gas by the passage over incandescent coal of a mixture
of air and superheated steam, the steam produced in a generator heated by the hot
gas coming from the gas generator drawing in air through a Giffard injector, the
air and steam being then superheated in an apparatus heated by the same gas,
the mixture of air and superheated steam circulating in reverse currents which
allows of charging through the top and insures the formation of gas free from
tar and smoke.
3. The washing and cooling of the combustible gas coming from the superheater
in a washer having a double column and a bottom cistern, one of the columns
being provided with perforated plates through which the water falls in a shower.
4. The arrangement of compressors, one for the gas coming from the washer,
the other for the air, these compressors being formed by the lower portion of the
motor cylinders beneath the pistons, excessive heating being prevented and lubri-
cation being facilitated by a circulation of cold water in the double jacket at the
bottom of the cylinders.
5. The construction of the recuperators formed of clusters of tubes in which
The compressed gas on the one hand and the compressed air on the other hand
become separately heated up to about 400° C. to the detriment of the products of
combustion.
6. The construction of the divider at the admission ports of the cylinders formed
by horizontal strips allowing gas and air to be spread in alternate thin layers in
order to be burnt in the interior of the cylinder, the spaces existing between the
said strips leading alternately into the gas valve chest and into the air valve chest.
7. The arrangement of igniter, by contact with which the mixture is fired,
formed by a bulbous disc of platinum heated red hot through the medium of the
flame of a spirit lamp.
S. The optional arrangement of the recuperator in the upper plate of the cylinder
with distinct chambers for the gas and air, the gas entering the cylinder in
vertical streams through pipes surrounded with air, the gas and air becoming
heated by contact with the hot plate, heated from within by the combustion and
from without by a circulation of the exhaust products.
9. Furnishing the wall of the upper chamber of the motor cylinders with thick
cast iron segments which are independent and isolated from one another so as to
have free expansion, and separated from the wall of the cylinder by a layer of
asbestos.
10. The construction of the piston of considerable height, the top of the piston
being formed of a plate separated from the body by a layer of asbestos.
11. The arrangement of the cylinders with direct admission of gas and air and
direct discharge of the products of combustion for the previous reheating of the
combustion chambers of the cylinders at the time the motor is started.
12. Operating the inlet and discharge valves of the compressors and of the
motors by means of cams, the shafts of which receive the movement of the motor
shaft.
13. The rigid union between the cam of the cylinder admission valve and that
of the exhaust valve of the compressor of the same fluid for preserving a constant
pressure in the recuperators under any conditions.
14. The relative shape of the admission cams of the gas and air so as to prolong

page_text: the duration of the admission of the air. after the gas has been shut off in order
to lower the final temperature of the burnt and expanded gaseous mixture.
15. The optional displacement of the cams on their shafts by means of guided
arms, which can be laterally displaced by means of a screw turning in the screw-
threaded arms, which allows of presenting to the valve levers projections of
varying sizes, and consequently of varying the duration of admission.
16. Operating the screw which actuates the guiding arms of the cams, either by
means of a hand wheel or by the regulator, substantially as herein before described.
Dated the 14th day of November 1889.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.