IMPROVEMENTS IN GAS MOTOR ENGINES
Year: 1883

page_text: LETTERS PATENT to Harry Townsend, Gas Manager, Edward Davies, and
Edward Charles Davies, Engineers, all of Bradford, in the County of York.
for an Invention of "IMPROVEMENTS IN GAS MOTOR ENGINES,"
PROVISIONAL SPECIFICATION left by the said Harry Townsend, Edward
Davies, and Edward Charles Davies at the Office of the Commissioners of
Patents on the 13th February 1883.
HARRY TOWNSEND, Gas Manager, EDWARD DAVIES and EDWARD CHARLES
DAVIES, Engineers, all of Bradford in the County of York "IMPROVEMENTS IN
GAS-MOTOR ENGINES,"
This invention has for its object so to improve the construction and action of gas
engines, as to enable them to yield increased power and to be made of greater
capacity, so as to perform work heavier and of greater variety than heretofore, and
is accomplished in the following manner.
In a horizontal engine there are two cylinders so arranged that one end of each
forms a working cylinder, in which the charge of air and gas mixed, is ignited, and
expanding gives the motive power to the engine, while the other end of each
cylinder acts as a compressing chamber in which the charges either of air, or of air
and gas mixed in suitable proportions are compressed before being admitted to the
working cylinders.
In one form of this engine the two working cylinders are both at the same
relative end of each cylinder, that farthest from the crank shaft, while the two
compressing chambers are both at that end of each cylinder that is nearest to the
crank-shaft, and are so arranged that the compressing chamber of one cylinder
supplies the charge to the working end of the other cylinder,-the communication
being by means of a passage between the two cylinders, which also acts as a
reservoir. The pistons of the two cylinders are both connected by rods and cranks
to the fly-wheel shaft and are so arranged that when one piston is at one end of
one cylinder, the other piston is at the opposite end of the other cylinder, so that
a charge is ignited when necessary with every stroke of the engine, both outward
and on its return.

page_text: Air is admitted in regulated quantities by means of simple disc valves, to the
compressing chambers, with every stroke of the engine and gas is admitted by
means of a valve controlled by the governor whenever necessary, so that should
there be no gas required for a charge, the air drawn into the compressing chamber,
would be duly compressed and conducted by means of the passage between the
two cylinders, to the opposite working cylinder, where it would give up in useful
effect the power absorbed in its compression and thus equalise the shock of the
previous explosion.
In addition to the valve controlled by the governor, there are two small disc
valves, one in the cover of each compressing chamber, working inside the pipe
leading the gas from the governor valve, and so arranged, that the suction of the
piston would open them, while when the piston is on its return stroke the pressure
in the compressing chamber would keep them tightly closed against their respec-
tive seats, they being also each provided with a spring to shut them immediately
the piston gets to the end of its stroke. The object of this arrangement is to
enable one governor valve to suffice for both compressing chambers. The air
valves are of similar construction and so arranged that the suction of the piston
opens them and the return stroke closes them, a spring being also used to expedito
the-change-in-the-motion..
The compressed charges are admitted to the passage or reservoir between the
two cylinders, by means of a plug valve in the cover of the cylinders nearest the
crank shaft, worked by a rod and eccentric, on a shaft, rotating at right angles to
and receiving its motion from the crank shaft.
This plug valve is so arranged that having allowed the charge to pass from=one=
compressing chamber, it cuts off communication from that chamber, and moving
on, brings the other chamber into communication, and having allowed that charge
_also to pass; cuts it off on its-return.
The charges are admitted to the working cylinders by a similar plug valve
arrangement in the other cover of the cylinders, the only difference being that the
plug valve is worked by a sliding bar actuated by a rod and crank on the same
secondary shaft as the eccentric at the other end. This slide also works the
lighting arrangements which consist of two plug valves, with hollow plugs, con-
taining a small lighted jet of gas. The slide carries a tappet, which coming in
contact with a radius arm on the plug of the valve, carries it along until a port
in the side of the plug comes into line with a corresponding port in the cover
of the cylinder, and ignites the charge. The slide then moves on and releases
the radius arm, when a spring causes the plug to fly back into its place, and cuts
off communication.
Each working cylinder is provided with an exhaust valve quite independent of
the other valves and consists of a simple disc valve working in a chamber in the
cover of the cylinder, and connected to a rod, which is attached to a lever. This
lever is actuated by a tappet on the secondary shaft before mentioned, which
depresses it momentarily at certain intervals, and allows the spent gases to escape,
and being released a spring at the other end of the lever immediately pulls the disc
down upon its seat, the valve being so arranged that the pressure in the cylinder
helps to keep it closed.
A governor is fitted to the engine to control the speed by acting on a regulator
valve on the gas supply pipe, and receives its motion from gearing on the secondary
shaft.
In order to enable the engine to be worked at varying speeds at the will of the
attendant, should such a thing be desired, the governor would be driven by a
belt instead of gearing. The belt would work on two cones, one on the secondary
shaft and the other on the governor shaft. These cones would be inverted, so that
the base of the one on the secondary shaft would be in line with the apex of
that on the governor shaft, and vice versa. The belt would be guided by a fork
to which would be attached a lever provided with a handle for the attendant.
Should the attendant wish the engine to run slower he would shift the position of

page_text: the belt on the cones so as to accelerate the speed of the governors, when the
engine would gradually reduce in speed until the governors ran again at their
normal speed, and then the arrangement of the governor and gas supply valve
would come into play, and maintain the engine at its newly acquired speed; but
should the attendant on the other hand wish the engine to run quicker he would
shift the belt on the cones, so as to make the governors run slower when the
governor would allow gas to pass until the engine increased its speed to such an
extent that the governors ran again at their normal speed, which would be the
new speed at which the engine would now be maintained. The fork guiding tho
belt could also be attached, where necessary, to automatic apparatus for varying
the speed of the engine.
The cylinders would be kept sufficiently cool by allowing water to circulate
between them and water jackets, in the ordinary manner.
For very small engines a modification of this invention would be employed,
consisting of only one cylinder, in one end of which the charge would be com-
pressed and in the other end ignited, communication between the two ends of the
cylinder being by means of a passage either underneath or at one side of the cylinder,
all the other parts being the same in both types of engine and substantially as
hereinbefore set forth.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Harry Townsend, Edward Davies, and Edward Charles Davies in the
Great Seal Patent Office on the 10th August 1883.
HARRY TOWNSEND, Gas Manager, EDWARD DAVIES and EDWARD CHARLES
DAVIES, Engineers, all of Bradford, in the County of York "IMPROVEMENTS IN
GAS MOTOR ENGINES
"
This invention has for its object so to improve the construction and action of gas
engines as to enable them to yield increased power and to be made of greater
capacity, so as to perform work, heavier and of greater variety than heretofore, and
is accomplished in the following manner.
In a horizontal engine there are two cylinders so arranged that in the ends
1 and 2, Figs 1 and 2 the charge of mixed gas and air is ignited and expanding
gives the motive power to the engine, while the other ends 3 and 4 of the same
cylinders serve as compressing chambers in which the charges either of air, or of
air and gas mixed in suitable proportions are compressed before being admitted to
the working or motive power-end-of-the-cylinders.
In-one form of this engine the explosions take place in the same relative end of
each cylinder, namely that farthest from the crank shaft, while the two compressing
parts of the cylinders are both at that end nearest to the crank shaft. It is to be
understood in this specification that the parts marked-1 and 2 of the cylinders-are-
called the explosion chambers and the parts 3 and 4 of the same cylinders are
called the compressing chambers. The cylinders are so arranged that the
compressing chamber of one cylinder supplies the charge to the explosion chamber
of the other cylinder, the communication being by means of a passage 5 between
the two cylinders, which passage also acts as a reservoir. The pistons of the two
cylinders are both connected by rods and cranks to the fly wheel shaft 20, and the
arrangement is such that when one piston is at one end of one cylinder, the other
piston is at the opposite end of the other cylinder, so that a charge is ignited when
necessary with every outward stroke of each piston.
Air is admitted in regulated quantities by means of single disc valves to the
compressing chambers with every stroke of the engine, and gas is admitted by
means of a valve controlled by the governor whenever necessary, so that should
there be no gas required for a charge, the air drawn into the compressing chamber
would be duly compressed and conducted by means of the passage 5 between the
two cylinders to the opposite explosion chamber; where it would give up in useful
effect the power absorbed in its compression and thus equalise the shock of the
previous explosion.
In addition to the valve controlled by the governor there are two small disc
valves 7, one in the cover of each compressing chamber working inside the pipe
leading the gas from the governor valve, and so arranged that the suction of the
piston would open them, while when the piston is on its return stroke, the pressure
in the compressing chamber would keep them tightly closed against their respective
seats, they being also each provided with a spring to shut them immediately the
piston gets to the end of its stroke. The object of this arrangement is to enable
one governor valve to suffice for both compressing chambers. The air valves are of
similar construction and are so placed that the suction of the piston opens them,
and the return stroke closes them, a spring being also used to expedite the change
in the motion.
The compressed charges are admitted to the passage or reservoir 5 by means of
the plug valve 8 in the cover of the cylinders nearest the crank shaft, and is

page_text: worked by a rod and eccentric 9 and 10 attached to the shaft 11, rotating at right
angles to and receiving its motion from the crank shaft 20. Ordinary disc valves
can be used instead of the plug valve 8 when the motion produced by 9 and 10
will be unnecessary. The plug valve 8 is so arranged that having allowed the
charges to pass from one compressing chamber it cuts off communication from that
chamber and moving on, brings the other chamber into communication, and having
allowed that charge also to pass, cuts it off on its return.
The charges are admitted to the explosion chambers by a plug valve 12, placed
in the other cover of the cylinders. This valve is worked by a sliding bar 13
actuated by a rod 15 and crank 14, fixed on the same secondary shaft 11 as the
eccentric at the other end. Insted of the plug valve 12 double clack valves
similar to those described for the single cylinder engine may be used if desired.
The slide 13 also works the lighting arrangements which consist of two plug, or
slide valves each containing a small lighted jet of gas.
Each explosion chamber is provided with an exhaust valve 17, quite independent
of the other valves, and consist of a simple disc valve working in a chamber in
the cover of the cylinder and connected to levers 18, 18.-These levers are actuated
by tappets 19, 19, on the secondary shaft 11 and being depressed momentarily at
certain intervals, allow the spent gases to escape, and being released, a spring at
the other end of each lever immediately pulls the disc down upon its seat, the
valves being so arranged that the pressure in the cylinder helps to keep them
closed.
In order that the engine may be worked at varying speeds at the will of the
attendant, the governor 21 Fig 3 is driven by a belt 22 instead of gearing. This
belt works on two cones 23 and 24, one on the secondary shaft 11 Fig 2 and the
other on the governor shaft 25. The position of these cones are reversed to each
other, so that the base of the one on the secondary shaft 11 is in line with the
apex of that on the governor shaft 25. The belt 22 is guided by a fork 26
attached to a lever or screw 27 provided with a handle or wheel 28. Should the
attendant wish the engine to run slower, he would shift the position of the belt on
the cones so as to accelerate the speed of the governors, when the engine would
gradually reduce in speed until the governors ran again at their normal speed, and
then the arrangement of the governor and gas supply valve, would come into play
and maintain the engine at its newly acquired speed; but should the attendant
on the other hand wish the engine to run quicker, he would shift the belt on the
cones so as to make the governors run slower, when the governor would allow gas
to pass until the engine increased its speed to such an extent that the governors
ran again at their normal speed, which would be the new speed at which the
engine would now be maintained. The fork guiding the belt could also be attached
where necessary to automatic apparatus for varying the speed of the engine.
Fig 4 shows an arrangement adapted to centrifugal governors worked
automatically as by an exhauster governor at a gas works, and in which the
lever 31 attached to the slide 29 carrying the fork 30 would be connected to the
spindle of the exhauster governor.
Figs 5 and 6 represent a single cylinder engine in one end 32, of which the
charge is compressed and in the other end 34 is ignited, communication between
the two ends being provided by means of a passage 34, [equivalent to 5 in Fig 2]
either underneath or at one side of the cylinder. The compressed charge in
32 automatically opens the disc valve 35 and allows the charge to pass through the
port 36 into the passage 34 where it is confined by the clack valves 35 and 37 until
the time for admitting it to the explosion chamber 33, when a tappet on the
secondary shaft depresses the lever and raises the clack valve 37 and the charge by
its own pressure lifts the clack valve 38 and allows the combustible mixture to
enter the explosion chamber 33 when it is ignited at the slide 39 by a jet of gas,
while the clack_valve 38 prevents the exploded gases blowing back into the
passage 34.-In Fig 6, 40 represents the exhaust.
In each of the arrangements the cylinders are kept sufficiently cool by allowing

page_text: water to circulate between them and water jackets in the ordinary manner, and
wherever valves are spoken of, it is to be understood that plug, clack, slide, or disc
valves may be used respectively as found most convenient.
The arrangement for altering the speed of the engine is adapted for application
to existing engines and can be worked automatically for driving gas exhausters by
means of the ordinary gas governor.
Having now described and particularly set forth the nature of this invention
and the manner in which the same is or may be used or carried into effect, we
would observe in conclusion that we do not confine or restrict ourselves to the
precise details or arrangements which we have described or referred to as variations
may be made therefrom without deviating from the principles or main features of
this invention, but what we consider to be novel and original and therefore
_claim as the invention secured to us by the hereinbefore in part recited Letters
Patent is,
Firstly. The construction of gas engines, with the cylinders, valves, and
appliances for giving motion to the latter arranged substantially as herein described
and shown on the drawings in Figs 1 and 2.
Secondly. The arrangement for controlling the speed of the engine either
automatically or otherwise as herein described and shown on the drawings-in
Figs 3 and 4, and
Thirdly. The construction of single cylinder engines with valves, and appliances
for giving motion to the latter, arranged as herein described and shown on the