Year: 1898

page_text: We, HENRY JOSEPH MARIE PIE CAMUSAT DE RIANCEY, Manufacturer of Auto-
motor Vehicles, and PAUL LOUIS GEVIN, Mechanician, both of 3, Place Daumesnil,
Paris, France, do hereby declare the nature of this invention to be as follows:-
Our invention relates to gas engines on the four-phase cycle and consists of
improvements whereby to utilize the full expansion of the gases, the expansion
being carried to such extent that it may also assist the cooling of the cylinders.
The engine is illustrated in the accompanying drawings in which Figure 1
represents a section of the engine taken through the axis of the cylinders. Figure 2
is a plan of the cylinders. Figure 3 is an elevation also shewing a portion of the
distribution gear. Figure 4 shews the gearing for operating the shaft of the
distributing gear and the cam for operating the exhaust valve. Figure 5 shews
the electric igniting mechanism. Figure. 6 is a detail of the cam which forms
part of said mechanism.
The engine comprises a small cylinder A (Figures 1 and 3) in which works the
part a of the piston of smaller diameter and a larger cylinder B (Figures 1 and 3)
in which works the part of the piston of larger diameter. The two cylinders are
placed in line and may either form one casting or be fitted together by a tight
joint. They may also be placed side by side without interfering with the inven-
tion. For engines of small power the cylinders would be provided with gills while
in the case of large engines the cylinders would be water-jacketted.
At one side of the cylinders is placed an explosion chamber C (Figures 1, 2,
and 3) communicating at its lower end with the large cylinder B and at its upper
end with the small cylinder A the latter passage being under the control of a
valve D (Figure 1). At E is provided an exhaust valve (Figures 1 and 2) for
the discharge of the burnt gases and at the side of the said chamber and opening
thereinto is an igniting device d (Figures 1 and 3). The end of the smaller
cylinder is closed by a cover F (Figures 1 and 3) fitted with an automatic admission
valve G (Figure 1) for the explosive mixture and also carrying the seat for the
communication valve D.
The distribution shaft H (Figures 1, 3, 4, and 5) is revolved at half the speed
of the driving shaft through the intermediate gear wheels IJ (Figures 1 and 4).
The shaft H drives:-
(1) A cam L (Figures 1 and 3) actuating the communication valve D through

page_text: the rod 9 (Figure 1) which works at k (Figure 1) as a piston to ensure a tight joint
at the point of entry into the explosion chamber; (2) a cam M (Figures 1 and 4)
for operating the exhaust valve E; (3) a helical cam N (Figures 1, 5, and 6) for
producing the spark the cam being capable of longitudinal adjustment on shaft H.
The motion of the pistons is transmitted to the driving shaft 0 (Figures 1 and 3)
by means of a connecting rod and a pair of crank discs PP1 (Figure 1) and upon
the end of shaft O is keyed a ring Q (Figures 1 and 5) which is toothed upon
about one-fourth of its circumference and for half its breadth. This ring is
electrically insulated from shaft O and its smooth part is in permanent contact
with a brush R (Figures 1 and 5) which is itself electrically insulated from the
engine and connected by means of a wire with a source of electricity. SS¹
(Figures 1 and 5) is a pair of levers keyed on a shaft T the lever S being provided
with a friction roller held in contact with cam N by a spring U (Figure 5) and
the lever Scarrying a flexible strip V (Figure 5) which is insulated from the
engine and in the primary circuit. A governor mounted in the crank disc P
(Figure 1) consists of a centrifugal weight X capable of moving outward from
the centre under the action of centrifugal force and retracted by the spring Y.
The weight in moving carries with it the cone Z (Figure 1) against which is
pressed by means of a spring e, one end of a rod d which passes centrally through
the shaft Q, the other end of said rod bearing against the forked lever e (Figures 1
and 5) which by oscillating on its centre f shifts the cam N laterally.
Supposing the pistons to be at the end of their backward stroke, that is to say
at the top end in the drawing, communication valve D being closed and valve E
open. By then moving the fly wheel in the direction of the arrow (Figure 3) the
smaller piston in descending inhales the explosive mixture through the automatic
valve G while the larger piston draws in air through the exhaust valve E. During
the return stroke the small piston compresses the mixture inhaled while the large
piston expels the air through the valve E which remains open. Just before the
end of this stroke the valve D opens under the action of cam L while cam M
closes valve E. The mixture compressed in the small cylinder passes into
chamber C where on contact with the igniting device the explosion takes place,
the impulse taking effect upon both pistons and expansion taking place simul-
taneously in both cylinders. It will be seen that the degree of expansion (which
may be very high) depends solely upon the ratio of the capacities of the two
cylinders, inasmuch as the mixture inhaled in the one cylinder expands in both.
The expansion being complete, the burnt gases are expelled without noise. During
the next return stroke the gases contained in the small cylinder are driven into
chamber C through the valve D which has remained open and are thence exhausted
along with those contained in the large cylinder through the exhaust valve E.
The valve D closes immediately after the escape of the burnt gases and valve E
remaining open the cycle is repeated in the order above indicated.
"
On the lever S being oscillated by the cam N so as to bring the flexible strip
in contact with sleeve Q the primary circuit is closed every time that the point
of a tooth on said sleeve makes contact with the strip V and is broken whenever
said strip comes opposite the spaces between the teeth, the succession of breaks
thereby produced generating in the induction coil the induction current which
produces the ignition spark between the terminals of the sparking device d.
When the engine speed varies, the weight X moves away from or towards the
centre and causes the cone Z to impart a sliding movement to rod d which in tum
shifts the cam N through lever e, this movement, owing to the helical form of the
acting part of the cam, causing the lever for establishing electric contact to be
brought into action earlier or later as the case may be, the later action having for
effect to reduce the speed of the engine as in this case the ignition takes place
when a portion of the working stroke has been performed whilst the earlier action
produces an explosion before the pistons reach the dead point so that during the
working stroke the combustion being complete the greatest effect is produced.
It will be understood from the foregoing that:
5

page_text: (I) By the communication of the cylinders through valve D the complete
expansion of the gases is obtained;
(II) This expansion being caused below atmospheric pressure assists in cooling
the cylinders;
(III) The sleeve and flexible strip V produce the interruptions necessary for
the generation of induction currents in an induction coil and enables the use of a
vibrating circuit-breaker, which has the objection of continually getting out of
order when in use, to be dispensed with;
(IV) The automatic acceleration or retardation of the ignition by means of the
governor furnishes an efficient means of maintaining constant the speed of the
engine.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
Improvements in Internal Combustion Engines.
We, HENRY JOSEPH MARIE PIE CAMUSAT DE RIANCEY, Manufacturer of Auto-
motor Vehicles, and PAUL LOUIS GEVIN, Mechanician, both of 3, Place Daumesnil,
Paris, France, 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:-
Our invention relates to gas engines on the four-phase cycle and consists of
improvements whereby to utilize the full expansion of the gases, this expansion
being carried to such extent that it may also assist the cooling of the cylinders.
Ignition may be effected by an electric spark or by an ignition_tube.
The engine is illustrated in the drawings accompanying our Provisional Speci-
fication in which Figure 1 represents a section of the engine taken through the
axis of the cylinders. Figure 2 is a plan of the cylinders. Figure 3 is an elevation
also shewing a portion of the distribution gear. Figure 4 shews the gearing for
operating the shaft of the distributing gear and the cam for operating the exhaust
valve. Figure 5 shews the electric igniting mechanism. Figure 6 is a detail of
the cam which forms part of said mechanism.
The engine comprises a small cylinder A (Figures 1 and 3) in which works the
part a of the piston of smaller diameter and a larger cylinder B (Figures 1 and 3)
in which works the part of the piston of larger diameter. The two cylinders are
placed in line and may either form one casting or be fitted together by a tight
joint. They may also be placed side by side without interfering with the inven-
tion. For engines of small power the cylinders would be provided with gills while
for large engines the cylinders would be water-jacketted.
At one side of the cylinders is placed an explosion chamber C (Figures 1, 2,
and 3) communicating at its lower end with the large cylinder B and at its upper
end with the small cylinder A the latter passage being under the control of a
valve D (Figure 1). At E is provided an exhaust valve (Figures 1 and 2) for
the discharge of the burnt gases and at the side of the said chamber and communi-
cating therewith is an igniting device d' (Figures 1 and 3). The end of the smaller
cylinder is closed by a cover F (Figures 1 and 3) in which is fitted a self-acting
admission valve G (Figure 1) for the explosive mixture and also the communication
valve D.
The distribution shaft H (Figures 1, 3, 4, and 5) is revolved at half the speed

page_text: of the driving shaft through the intermediate gear wheels IJ (Figures 1 and 4).
The shaft H carries:
-
(1) A cam L (Figures 1 and 3) actuating the communication valve D through
the rod g (Figure 1) which works at k (Figure 1) as a piston to ensure a tight joint
where it enters the explosion chamber;
(2) A cam M (Figures 1 and 4) for operating the exhaust valve E;
(3) A helical cam N (Figures 1, 5, and 6) for producing the spark, this cam being
capable of longitudinal adjustment on shaft H.
The motion of the pistons is transmitted to the driving shaft 0 (Figures 1 and 3)
through a connecting rod and a pair of crank discs PPI (Figure 1) and upon
the end of shaft is keyed a ring Q (Figures 1 and 5) which is toothed upon
about one-fourth of its circumference and for half its breadth. This ring is
electrically insulated from shaft O and in permanent contact with its smooth
part is a brush R (Figures 1 and 5) which is electrically insulated from the
engine and connected by a wire with a source of electricity. $ $¹
(Figures 1 and 5) are a pair of levers keyed on a shaft T the lever S being provided
with a friction roller held in contact with cam N by a spring U (Figure 5) and
the lever Scarrying a flexible strip V (Figure 5) which is insulated from the
engine and is in the primary circuit. A governor mounted in the crank disc P
(Figure 1) consists of a centrifugal weight X capable of moving radially outward
when the centrifugal force overcomes a spring Y. The weight carries with it a
cone Z (Figure 1) against which is pressed by a spring c, one end of a rod d which
passes axially through the shaft O and bears against a lever e pivoted at f
(Figures 1 and 5) which engages by its forked end with cam N so as when oscil-
lated to shift the cam N laterally.
Supposing the pistons to be at the end of their backward stroke, that is to say
at the top end in the drawing, communication valve D) being closed and valve E
open. By then moving the fly wheel in the direction of the arrow (Figure 3) the
smaller piston in descending inhales the explosive mixture through the automatic
valve G while the larger piston draws in air through the exhaust valve E. During
the return stroke the small piston compresses the mixture inhaled while the large
piston expels the air through the valve E which remains open. Just before the
end of this stroke the valve D opens under the action of cam L while cam M
closes valve E. The mixture compressed in the small cylinder passes into
chamber C where on contact with the igniting device the explosion takes place,
the impulse taking effect upon both pistons and expansion taking place simul-
taneously in both cylinders. It will be seen that the degree of expansion (which
may be very high) depends solely upon the ratio of the capacities of the two
cylinders, inasmuch as the mixture inhaled in the one cylinder is expanded in both.
The expansion being complete, the burnt gases are expelled without noise. During
the next return stroke the gases contained in the small cylinder are driven into
chamber C through the valve D) which has remained open and are thence exhausted
along with those contained in the large cylinder through the exhaust valve E.
The valve D closes immediately after the escape of the burnt gases and valve E
remaining open the cycle is repeated in the order above indicated.
On the lever S being oscillated by the cam N so as to bring the flexible strip V
in contact with sleeve Q the primary circuit is closed every time that the point
of a tooth on said sleeve makes contact with the strip V and is broken whenever
said strip comes opposite the spaces between the teeth, the succession of breaks
thereby produced generating in the secondary circuit of the induction coil the
current which produces the ignition spark between the terminals of the sparking
device d. When the engine speed varies, the weight X moves away from or
towards the centre and causes the cone Z to impart a sliding movement to rod d
which in turn shifts the cam N through lever e, this movement owing to the
helical form of the acting part of the cam causing the lever for establishing electric
contact to be brought into action earlier or later, as the case may be, the speed
of the engine being reduced when the ignition is retarded since the explosion is

page_text: delayed until a portion of the working stroke has been performed whereas early
ignition produces the explosion just before the pistons reach the dead point so
that during the working stroke the combustion, being complete, produces its
maximum effect.
It will be understood from the foregoing that
(I) By the communication of the cylinders through valve D the complete expan-
sion of the gases is obtained;
(II) This expansion being carried below atmospheric pressure assists in cooling
the cylinders;
(III) The sleeve Q and flexible strip V produce the interruptions necessary for
the generation of induction currents without the use of a vibrating circuit-breaker,
which has the objection of continually getting out of order;
(IV) By the automatic timing of the ignition by means of the governor the
speed of the engine is maintained constant.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. The herein described gas or carburetted air engine consisting of the parts
combined arranged and operating substantially as specified.
2. The herein described gas or carburetted air engine consisting essentially in
the combination with the cylinders A and B and their pistons a b, of an explosion
chamber C common to both, a valve D whereby both cylinders may be put in
connection with the said chamber C for the purpose of effecting the complete
expansion, and admission and exhaust valves GE, and ignition timing mechanism
consisting in the combination of the centrifugal governor X and the helical cam N
adjustable for determining the moment of ignition and so regulating the speed
of the engine substantially as specified.
Dated this 4th day of January 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.