Improvements in and relating to Explosion-engines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Explosion-engines.
We, RAPHAËL FENELON ODILE CHAUVIN, and RENÉ ARNOUX, both of 186, Rue
Championnet, Paris, in the Republic of France, Engineers, do hereby declare the
nature of this invention to be as follows:-
In explosion engines as at present constructed, the chamber containing the
distributing valves, slide-valves or equivalent parts, is in direct and permanent
communication with the rear-end of the cylinder, that is to say, with that part at
which the temperature of the gases is highest and consequently most pernicious to
the preservation of the materials of which the said valves or the like are con-
structed and to their fluid-tightness. Indeed, these parts, necessarily of delicate
construction, are subjected to the action of the gas at a very high temperature,
which, by making the metal porous, gives rise to leakages, diminishes the power
of the motor, affects the regulation of the compression and the firing, and, moreover,
permits dangerous flashes of flame to pass through the admission-valve into the
carburettor.
According to the present invention the chamber containing the distributing
valves is made to open into the cylinder not at the rear end thereof but at a suit-
able part of the cylindrical wall thereof in such 3 manner that the
admission passage will be completely covered and closed by the piston
when the said piston arrives at the end of its stroke. Experience has shown that
the opening or openings provided in this part of the wall do not interfere with the
efficient working of the piston and its packing-rings. This new arrangement of
parts whereby the distributing-valve chamber communicates with the cylinder
through an opening in' the cylindrical wall thereof suitably situated so as to be
screened by the piston during part of its stroke, permits the compression of the
explosive mixture to take place in a practically air-tight closed chamber (or cul-
de-sac) formed by the rear end of the cylinder and the piston, since the cylinder
is no longer in communication with the chamber containing the distributing
valves.
The causes of leakages are therefore reduced to those which arise from the piston
alone, that is to say, to the minimum possible, and, furthermore, this condition is
attained at the exact moment of the explosion of the mixture when the pressuro
and the temperature are at their maximum value.
The herein described arrangements also permit the distributing valves to be
shielded from the high temperature caused by the explosion of the gases, since
these latter can only come in contact with the said valves when they are already
appreciably expanded, that is to say, at a temperature much lower than that pro-
duced at the moment of explosion.
Moreover our arrangements permit the explosive gases to be expanded as much
as is necessary to ensure economical working of the engine, to which our improve-
ments can be applied without any alteration except the placing of the chamber
containing the distributing valves at a suitable point along the wall of the cylinder.
It is true our construction permits a large part of the burnt gases from the previous

page_text: explosion to remain in the cylinder, but experience shows that even when the pro-
portion of fresh gas admitted is reduced to 10 per cent. of the total volume, the
mixture can be certainly fired by any of the known methods of firing, such as
electric ignition, tube ignition or the like.
Our invention will be readily understood from the following description, refer-
ence being had to the accompanying drawing, in which we have shown our
improvements as applied to motors provided with lift-valves as distributors.
The said drawing shows a plan, partly in horizontal section, of an ordinary
four-cycle engine having our invention applied thereto.
As shown in the drawing the inlet-valve a is arranged in the body of the
cylinder A opposite to the exhaust-valve b. :
These two valves open into a chamber c cast on the cylinder in a suitable position
to permit the piston B to entirely cover the entrance from this chamber to the
cylinder when the said piston arrives at the end of the stroke compressing the
explosive mixture.
The inlet valve opens automatically and the exhaust valve is actuated by a
connecting-rod driven by a toothed wheel acting as a crank and geared with a
pinion keyed on the main shaft; this pinion and toothed-wheel having a velocity
ratio of 1 to 2.
1
The lines L M indicate the extreme positions of the piston.
Improvements in and relating to Explosion-engines.
We, RAPHAEL FENELON ODILE CHAUVIN and RENÉ ARNOUX, both of 186, Rue
Championnet, Paris, in the Republic of France, Engineers, 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;
-
In explosion engines as at present constructed, the chamber containing the
distributing valves, slide-valves or equivalent parts, is in direct and permanent
communication with the rear-end of the cylinder, that is to say, with that part at
which the temperature of the gases is highest and consequently most pernicious to
the preservation of the materials of which the said valves or the like are con-
structed and to their fluid-tightness. Indeed, these parts, necessarily of delicate
construction, are subjected to the action of the gas at a very high temperature,
which, by making the metal porous, gives rise to leakages, diminishes the power
of the motor, affects the regulation of the compression and the firing, and, moreover,
permits dangerous flashes of flame to pass through the admission valve into the
carburettor.
According to the present invention the chamber containing the distributing
valves is made to open into the cylinder not at the rear end thereof but at a suit-
able part of the cylindrical wall thereof in such a manner that the passage or pas-
sages leading into this chamber will be completely covered and closed by the piston
when the said piston arrives at the end of its stroke. Experience has shown that
the opening or openings provided in this part of the wall do not in any way inter-
fere with the efficient working of the piston and its packing-rings. This new
arrangement of parts whereby the distributing-valve chamber communicates with
the cylinder through an opening in the cylindrical wall thereof suitably situated
so as to be screened by the piston during part of its stroke, permits the said piston

page_text: to compress the explosive mixture in a practically air-tight closed chamber (or cul-
de-sac) formed by the rear end of the cylinder and the piston, since the cylinder
is no longer in communication with the chamber containing the distributing
valves.
The causes of leakages are therefore reduced to those which arise from the piston
alone, that is to say, to the minimum possible, and, furthermore, this condition is
attained at the exact moment of the explosion of the mixture when the pressure
and the temperature are at their maximum value.
The herein described arrangements also permit the distributing valves to be
shielded from the high temperature caused by the explosion of the gases, since
these latter can only come in contact with the said valves when they are already
appreciably expanded, that is to say, at a temperature much lower than that pro-
duced at the moment of explosion.
Moreover our arrangements permit the explosive gases to be expanded as much
as is necessary to ensure economical working of the engine, to which our improve-
ments can be applied without any alteration except the placing of the chamber
containing the distributing valves at a suitable point along the wall of the cylinder.
It is true our construction permits a large part of the burnt gases from the previous
explosion to remain in the cylinder, but experience shows that even when the pro-
portion of fresh gas admitted is reduced to 10 per cent. of the total volume, the
mixture can be certainly fired by any of the known methods of firing, such as
electric ignition, tube-ignition or the like.
Our invention will be readily understood from the following description, refer-
ence being had to the drawing filed with our Provisional Specification, which is a
plan partly in horizontal section, of an ordinary four-cycle engine having our
invention applied thereto and provided with lift-valves as distributors.
As shown in the drawing the inlet-valve a is arranged in the body of the
cylinder A opposite to the exhaust-valve b.
These two valves open into a chamber c cast on the cylinder in a suitable position
to permit the piston B to entirely cover the entrance from this chamber to the
cylinder when the said piston arrives at the end of the stroke compressing the
explosive mixture.
The inlet-valve opens automatically and the exhaust valve is actuated by a
connecting-rod driven by a toothed wheel acting as a crank and geared with a
pinion keyed on the main-shaft; this pinion and toothed-wheel having a velocity
ratio of d to 2.
The lines L M indicate the extreme positions of the piston.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what we
claim is:
In a four-stroke-cycle gas or petroleum motor, arranging the opening or open-
ings through which the cylinder communicates with the chamber containing the
valves or the like, in such a position that the said opening or openings will be
entirely closed by the piston when the same arrives at the end of the stroke to
effect the compression of the explosive mixture, substantially as described with
reference to the accompanying drawing, and for the purposes specified.
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicants.