IMPROVEMENTS IN THE CONSTRUCTION AND ARRANGEMENT OF GAS ENGINES
Year: 1883

page_text: LETTERS PATENT to Paul Niel of Saint Lukes Squaro Millwall London for an
Invention of "IMPROVEMENTS IN THE CONSTRUCTION AND ARRANGEMENT OF
GAS ENGINES"
PROVISIONAL SPECIFICATION left by the said Paul Niel at the Office of the
Commissioners of Patents on the 25th June 1883.
PAUL NIEL [of Saint Lukes Square Millwall London]
CONSTRUCTION AND ARRANGEMENT OF GAS ENGINES
"IMPROVEMENTS IN THE
My Invention relates to improvements in the construction and arrangement of
Gas Engines and has for its object to vary automatically the volume of mixture of
gas and air, and its compression before ignition, the mixture being in each case in
the same proportion. The result being that different pressures are obtained upon
the piston after ignition, and that the hot gases which escape are at a lower
temperature, being nearly at the atmospheric pressure and so giving a maximum
duty at each stroke according to the work done, and a more regular spoed
My invention consists in the application of one cylinder or more having a single
action This cylinder has two different diameters lengthways and a common
piston working in it and fitting at either end the two different diameters of the
cylinder. The cylinder is closed at the smaller end which is the ignition side, and
open at the larger end where the connecting rod is attached, to move the crank;
the internal annular space formed by the two different diameters of the piston is
used as a pump
When the piston moves forward after the ignition of the gases the pump in the
first part of its stroke sucks the contents from a reservoir with which it is in
communication by means of a port and recess in the trunk of the smaller piston,
and in the last part of its stroke this communication being interrupted it sucks
atmospheric air through a valve which is provided and also gas from the main
supply pipe through another valve which is provided. The area of the gas supply
pipe being so regulated as to let the same relative volume of gas and air pass at
each stroko
When the piston moves backward the exhaust is opened to the atmosphere and
the back face of the smaller piston is put in communication with the pump by

page_text: means of a suitable valve and ports, and in the first part of its stroke forces a part
of the contents of the pump into the space behind and thus blows out the products
of combustion and takes their place, then the exhaust closes as does also the
communication with the pump. In the last part of the stroke the pump is open to
the reservoir above named, and the smaller piston compresses the mixture; during 5
this part of the stroke the exhaust port may be more or less open to the reservoir,
and this may be regulated by a small slide valve on the exhaust port: when this
valve is closed a maximum pressure is obtained, and when it is more or less open-
a portion of the mixture of gases escapes to the reservoir and so a greater or less
pressure is obtained. The smaller slide valve is actuated by friction on the larger 1
valve or by other means and is stopped by a cam regulated by the governor-The
larger slide valve is used to open the exhaust and so put the pump and smaller
cylinder in communication and also to effect the ignition, it is worked by a cam or
eccentric on the crank shaft.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Paul Niel in the Great Seal Patent Office on the 22nd December
1883.
'
PAUL NIEL of Saint Luke's Square, Millwall London
CONSTRUCTION AND ARRANGEMENT OF GAS ENGINES
"
"IMPROVEMENTS IN THE
My Invention relates to improvements in the construction and arrangements of
Gas engines and has for its object to vary automatically the volume of mixture
of Gas and air and its compression beforo ignition the mixture being in each case
in the same proportion the result being that different pressures are obtained upon
the piston after ignition and that the hot gases which escape are at a lower
temperature, being nearly at the atmospheric pressure and so giving a maximum
duty at each stroke according to the work done and a more regular speed.
In carrying out my Invention any desired number of cylinders may be employed
arranged in any suitable manner but for the sake of simplicity I have confined my
description to one single action cylinder only. This cylinder is of two different
diameters lengthways and has a piston working in it, of two different diameters
corresponding to and fitting the two different diameters of the cylinder. The
cylinder is closed at the smaller end which is the ignition side and open at tho
larger end, where the connecting rod is attached to move the crank; the internal
annular space formed by the two different diameters of the piston is used ns a
pump.
When the piston moves forward after the ignition of the gases, the pump in
the first part of the stroke sucks the explosive mixture from a reservoir with
which it is in communication by means of a port and recess in the trunk of the
smaller piston; and in the last part of its stroko this communication being
interrupted it sucks atmospheric air through a valve and also gas from the main
supply pipe through another valve, the area of the gas supply pipe being so
regulated as to let the saine relative volume of gas and air pass at each stroke.
When the piston moves backward the exhaust passage is opened to the atmo-
sphere and the back face of the smaller piston is put in communication with the
pump by means of a suitable valve and ports and in the first part of its stroke the
pump piston forces a part of the contents of the pump into the space behind an-I
thus blows out the products of combustion and takes their place. The exhaust
port then closes and the communication with the pump is cut off. In the last
part of the stroke the pump is open to the reservoir herein before named and the
smaller piston compresses the mixture; during this part of the stroke the exhaust
port may be more or less open to the reservoir, which opening may be regulated
by a slide or other suitable valve in the exhaust port. When this valve is closed a
maximum pressure is obtained and when it is more or less open a portion of the
mixture of Gases escapes to the reservoir and so a greater or less pressure is
obtained. This slide valve may be actuated by friction on the main valve or by
other means and is stopped by a cam surface regulated by the governor. The
main slide valve which is used to open the exhaust and so put the pump and
smaller cylinder in communication and also to effect the ignition is worked by a
cam or eccentric on the crank shaft.
And in order that my said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 is a side clevation of a gas engine constructed according to my.
Invention a portion of the cylinder being broken away to shew the interior.

page_text: thereof. Figure 2 is a transverse section taken along the line 1-2 in Figure 1
shewing the air and gas valves. Figure 3 is a plan and partial horizontal section,
through the cylinders, pistons and slide valves, and Figure 4 is a transverse section
taken along the line 3-4 in Figure 1 through the regulating valve and governor
arrangement.
A is the small part of the cylinder wherein the explosion is produced for
propelling the trunk piston C in the direction of the arrows. This part of the
cylinder is kept cool by a current of water which is caused to circulate between it
and an outer cylinder or jacket A¹. B is a pump cylinder of larger diameter than,
but forming a continuation of the cylinder A. In the cylinder B is fitted to work
a piston D connected to or formed in one with the piston C. The pump piston D
in its forward motion sucks explosive mixture into the cylinder B first from the
contents of the reservoir M and continues to do so so long as a recess N in tho
piston C is open to the port O communicating with the said reservoir; then when
that communication is closed it sucks air through the valve Q and the port R and
gas through the valve S and the ports 1 in the cylinder and 2 in the main slide
valve I.J. The piston D is connected to the crank shaft G by a rod E and on this
shaft is an eccentric H which imparts motion to the main slide valve I. J. If
desired the main valve I, J, may be made in two parts connected together by links
or otherwise so as to work together; one part to contain the ports for the exhaust
and for conducting surplus mixture to the reservoir and the other part containing
the parts communicating with the pump-and ignition cylinder and also the ignition
port.
In the forward motion of the pistons (in the direction of the arrows) after the
communication between the recess N with the port O is closed the mixture of air
and gas is sucked in by the pump through the valves Q and S so long as the port 1
is open to the port 2 but by the motion of the slide I, J, the communication
between these ports is closed before the stroke of the pistons is completed, so that
during the remaining portion of the stroke air alone is sucked through the valve Q
sufficient to fill up the port R. The pistons having completed their forward stroke
commence to move backward at which time the valve I, J, will have moved and
opened a communication between the interior of the small cylinder A and tho
exhaust pipe 3 by the ports 4 and 5, so that by the back motion of the piston C a
portion of the products of combustion in the cylinder is forced out through the
exhaust pipe 3. The conical part L of the piston C having at its smaller end a
lateral port K is then in communication by the ports 12, 11, 10 and R with the
larger or pump cylinder B. By the continued backward motion of the piston the
air from the port R and the mixture from the pump cylinder B are forced through
the ports 10, 11, and 12 into the lateral port K of the cone L thence forcing the
products of combustion remaining in the cylinder A through the exhaust pipe 3.
The volume of the mixture thus supplied by the pump is sufficient to fill up that
part of the small cylinder A in front of the piston previously occupied by the
products of combustion, the main valve having moved into the position shewn in
Figure 3 so as to close the exhaust port 3. The piston C continuing its back ward
course, compresses the mixture in the hollow part L(which is the combustion chamber)
whilst the large piston D forces the remaining contents of the pump B into the
reservoir M through the recess N and port O which are at that time in communi-
cation. The quantity of mixture forced into the small cylinder by the pump is
the maximum volume that can be exploded if the engine requires its whole amount
of power.
When the maximum volume of the mixture is introduced into the
cylinder A and the piston C has completed its back stroko it follows that after the
explosion and when the piston is at the end of its forward stroke the products of
combustion will be greater in volume than that of the mixture introduced. The
expansion of the gases produced by the explosion is brought at the end of the
stroke to a lower pressure than in Engines which expand the gases to the voluine
of the gases when introduced, whilst the temperature of the products of combustion
is reduced and more useful work produced than in that kind of Engines referred

page_text: to. If by diminution of work the speed is increased a varied and smaller quantity
of the mixture will only be exploded; the other part of the mixture being forced
when the compression takes place through the ports 5, 4, 6, 7, 8 and pipe 9'into
the reservoir M.
To produce this result a small valve T, moving by friction or otherwise with the
main slide valve I, J, has fixed on it a piece U which by coming into contact with
one of a series of steps or cam surface V on the governor rod, is shifted so as to
open more or less the port 7, in the small valve T, with the ports 6 and 8 in the
main valve I J and according to the extent of the opening of these ports so will
the quantity of the compressed mixture forced or sucked in to the reservoir M
from the cylinder A be regulated so long as the ports 4 and 6 are in communication
with the cylinder by the port 5. .The mixture thus sent in to the reservoir M will
then be sucked or drawn into the pump cylinder B by the next succeeding forward
stroke of the piston D before any more air and gas is sucked in. The steps or cam
surface V present different heights to the knocking piece U for the purpose of
varying the opening of the ports 6, 7 and 8 in the following manner. When the
pistons C and D commence to move backward and before the port K in the small
piston C comes opposite the port 12 a small amount of compression is produced in
the pump
B and a part of the compressed air thon passes through the ports X,
13, 14, 15 and 16 to the underside of the governor piston Y in the small
cylinder Z raising that piston at each forward stroke of the engine. The air escapes
from the cylinder Z by a small aperture 17 which can be regulated by the screw 18.
As the oscape of the air through 17 and the weight of the piston Y are constant
it follows that the descent of the piston Y will be regular but as by the different
speeds of the engine the supply of the compressed air is varied for equal periods
of time, the height to which the piston Y is raised in the cylinder Z will accordingly
be varied and consequently also different heights of the cam surface or steps V will
relatively be brought into position to act upon the piece U.
If when the smallest volume of mixture is exploded the speed of the engine is
still in excess of its normal speed, the governor piston Y being then at the highest
position a piece 20 fixed on the governor rod is brought opposite a rod 21, which
is connected by means of the levers 22 and 23 with the gas valvo S, and prevents
the gas valve being opened at the next stroke of the Engine and thus prevents an
explosion taking place. The variations in the position of the steps or cam surface V
and the blocking piece 20 can bo produced by the motion of any kind of governor.
On the rod 21 are the nuts 24 by means of which the lifting of the valve S may
be adjusted to regulate the quantity of gas admitted proportionally to the air so
that different inflammable gases can be used in the same engine without any other
alteration than the regulating of the valve S by the nuts 24. The small valvo T
being moved by friction with the slide I J in the direction of the arrows conies in
contact with the face 19 of the main slide valve cover before the main valve has
completed its forward stroke so that in the backward motion of these slides the
communication between the ports 6, 7 and 8 and the port 5 with the reservoir M
through the pipe 9 are cut off when the gases are burning in the small cylinder A.
The explosion can be produced by any kuown means, as shewn in my drawings it
is produced by means of a burner 25 in the chamber P of the slide I J supplied
with Gas from the pipe 26. This burner is lighted at each stroke of the main
slide valve by a burner 27 kept constantly lighted and effects the explosion of
the gas in the cylinder through a small port 28 when it arrives opposite the
port 5.
Having now described and particularly ascertained the nature of my said
Invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that I do not confine myself to the particular
details of construction shewn and described but what I consider to be novel and
original and therefore claim as the Invention secured to me by the hereinbefore in
part recited Letters Patent is :-
First-In gas Engines automatically regulating or varying the volume and

page_text: compression of the explosive mixture in the ignition cylinder according to the
speed of the Engine in the manner and by the means substantially as hereinbefore
,described.
Second-In gas Engines the employment of a piston having a port or passage
or ports or passages capable of being brought into communication through the
valve with the pump cylinder in such a manner that as the products of
combustion from a previous explosion are being expelled from the ignition cylinder
by the motion of the piston a fresh charge of explosive mixture is being forced
through the port or ports or passage or passages in the piston and valve into the
ignition cylinder substantially in the manner hereinbefore described and illustrated
by my drawings.
Third-In gas Engines the employment in combination with the arrangement
claimed by the preceding second claiming clause of a reservoir for receiving the
surplus explosive mixture to be forced into the ignition cylinder for the next charge
or a portion of the next charge substantially in the manner herein before described
and illustrated by my drawings.
Fourth-In gas Engines the employment in combination with the main.slide
valve of an automatically actuated supplementary valve for regulating the
passage for the surplus explosive mixture from the ignition cylinder to the
reservoir substantially as herein before described and illustrated by my drawings."
Fifth-In gas engines regulating the traverse of the supplementary valve
referred to in the preceding fourth claiming clause by means of an automatically
adjustable stepped or cam piece controlled by a governor substantially in tho
manner and for the purpose hereinbefore described and illustrated by my
drawings.
•
Sixth-The general construction and arrangement of Gas Engines as herein-
before described and illustrated by my drawings.
In witness whereof. I the said Paul Niel lave to this-my-Specification set my
hand and seal this twentieth day of December One thousand eight hundred and
eighty three.
DATI NIM