IMPROVEMENTS IN GAS MOTOR ENGINES
Year: 1879

page_text: "
LETTERS PATENT to Joseph John Butcher, of Gateshead, in the County of
Durham, Engineer, for the Invention of IMPROVEMENTS IN GAS MOTOR
ENGINES."
Sealed the 23rd April 1880, and dated the 27th October 1879.
PROVISIONAL SPECIFICATION left by the said Joseph John Butcher at
the Office of the Commissioners of Patents on the 27th October 1879.
JOSEPH JOHN BUTCHER, of Gateshead, in the County of Durham, Engineer.
"IMPROVEMENTS IN GAS MOTOR ENGINES."
My Invention consists of improvements in gas motor engines, that is to say,
engines in which the impulse given to the piston or pistons is chiefly due to the
expansive force developed in the gases that result from a process of combustion
(the constituents of which will usually be coal gas and atmospheric air), and their
object is chiefly to render possible the construction of reversing engines suitable
for tramway; locomotive, hoisting, hauling, and other similar purposes, as well as
the simpler types of stationary engines.
t
In carrying out my Invention I prefer to use a slide valve for the distribution of
the gases within the cylinders of such a character that it both effects the admission
and emission (or exhaustion) of the gases to and from the cylinders, separate
passages however being used in the cylinder for these operations, and a check or
cut off valve, either self acting (as a clack valve) or actuated by mechanism, but in
either case so arranged as to prevent the back flow of the gases and flaine into the
supply passages when an increased pressure is set up within the cylinder by com-
bustion during the remainder of the time in which the main slide valve keeps the
induction (or supply) port open for the admission of the gas, this slide valve being
so arranged, where the engines are intended for reversing engines, as to enable the gas
to be admitted to the cylinder during at least 90° of the crank traverse, so that
when two double acting or four single acting cylinders are employed, at whatever
point in its revolution the crank inay be standing, a charge of explosive or com-
bustible gas may be admitted; by moving the slide valves from the reversing levers
behind one of the pistons in such manner that when its pressure is increased by
combustion it may, acting upon the piston, drive the crank forward in the direction
Price 8dr

page_text: desired. Thus coupled with the power given by an ordinary slide valve and
reversing gear as used in steam engines, of admitting a charge of combustible gas
to the cylinders at any point in the revolution of the crank shaft, so that it may,
when ignited, thrust the piston either forward or backward as desired, I obtain a
point of ignition and "cut off" entirely under control, and which may be made
either early as required for regular work or late as may sometimes be desirable in
starting the engine. when the piston requiring to be acted upon may be half way or
even more down its cylinder. The traverse of the main slide valve corresponding
with the forward and backward movement of the engine may be effected by two
separate eccentrics and rods, the one being set for forward motion and the other for
backward motion, and the. rod ends may be connected by a link so as to enable the
slide valve spindle to be worked off either one or the other eccentric at will, thus
effecting the reversing of the engine as in ordinary link motion used for steam
engines, or only one eccentric may be used, this eccentric being itself revolved
partially round the shaft to its forward or backward centre by means of a spiral
sleeve or similar device, or the different movements of the slide corresponding with
the reverse movements of the engine may be effected by some other convenient
means. Link motion is however to be preferred for ordinary purposes. Thus in
any case I obtain a valve so arranged that when the piston of one of the cylinders
of a common two cylinder reversing engine is at mid stroke (the other being on its
dead centre), a charge of combustible gas may be admitted to either, side of it while
the other side is opened to the exhaust passages, the tendency of the gas to return
through the inlet port when the pressure is increased within the cylinder by com-
bustion being checked by a check or cut off valve as described.
To effect the ignition of the gaseous charges within the cylinders I prefer to use a'
separate slide valve, and in most cases to effect this ignition from a permanent gas
jet outside the cylinder. When the cut off of the combustible gas is effected by
means of a valve worked mechanically; the ignition of the gases within the cylinder
may be effected by the same means. The operation of communicating ignition
from outside the cylinder into the charge of combustible gas (generally at a pressure
above that of the atmosphere) within it may be effected by any of the means
commonly in use in gas engines. It has however be found by experiment that a
simple means of carrying a flame from the open atmosphere into an enclosed
chamber in the manner required is to rapidly shear off the conical body of an
ordinary flame leaving only the base to keep the jet alight due to the combustion
of a jet of carburetted hydrogen or other gas burning at its surfaces of contact
with the oxygen of the surrounding air. The fact that under these circumstances
the constituents of combustion are, to a considerable extent, separated from one
another, the luminous cone of flame enclosing within it a core of gas, and being
surrounded by an envelope of atmospheric air renders this flame for an instant self
supporting after it has been withdrawn into an enclosed space within which it is
cut off both from the source of its gas supply and from all the atmospheric air
except that portion which immediately surrounds it, combustion being sustained
until the unburned gas within the luminous cone is consumed. Thus this flame
may be momentarily enclosed in a pocket from which all communication with the
atmosphere is shut off and with which a communication may be safely made with
the combustible charge within the cylinder so as to ignite it. This operation may
be effected mechanically in several ways. According to one of these the gas jet
outside the cylinder is allowed to burn freely through a hole in a sliding bar, such
hole being somewhat larger than the body of the flame, so as to enable it to
contain a small reserve of air for the combustion of the core of gas after it has
been shut off from all communication with the atmosphere. The lower surface of
this sliding bar is somewhat above the level of the nozzle from which the gas jet
springs, so that when the bar is actuated it shears off the body of the flame only
leaving its root or lower part alight, and thus does not put it out altogether.
Immediately on shearing off the flaine the bar is made to slide between a pair of
properly scraped surfaces making a completely air tight joint so as to effectually

page_text: shut in the hole within which the flame is being carried. As soon as the hole is
completely shut in between these surfaces, and thus any escape of the gas rendered
unlikely, the onward movement of the flame carrying bar brings this flame pocket
into open cominunication with a hole or port in the cylinder through which contact
is effected between the combustible inixture of gas and air contained therein and
the flame in the pocket described, and thus ignition is effected. When the port in
the cylinder through which ignition is effected is liable to contain foul air from the
last charge, such air or rather incombustible gas being partially compressed by the
ingress of the new charge of combustible mixture, means may be employed to clear
it and allow it to fill with a strong charge of the mixture of inflammable gas
described. This may be done by allowing a slight momentary escape of gas from
the port. The need of such escape inay however be avoided either by allowing the
stream of combustible gas as it enters the cylinder to flow partially through this
ignition port, or by providing in the face of the ignition slide described above a
recess which shall face the ignition port in the cylinder at the time when the
inrush of explosive gas takes place, so that by compression any remaining burnt
gases from the last charge may be forced home into this recess, and will therefore,
when the slide moves forward to carry the flame pocket towards this ignition port,
the recess before mentioned partaking of the movement of the slide shall carry
away with it the remaining foul air in the port, so clearing the same and allowing
it to fill with a strong charge of combustible gas.
The ignition slide may be actuated either from any of the moving gear
conveniently situated for the purpose, or from a separate crank, eccentric, or cam
upon the main crank shaft. It is however necessary that its motion when con-
veying the flame shall be of a rapid character, so that combustion may be sustained
during the transit from the open air to a position opposite the ignition port. This
rapid movement may be obtained when the movement of the actuating gear is too
slow for the purpose by means of a spring, so arranged that it is first drawn into
tension by the said gear, which latter by then releasing a catch allows the igniting
slide to rapidly follow it, carrying the flame pocket and flame forward with a
springing notion towards the igniting port. If the spring catch is now made to
hold the bar in this position until the gear moves backward through half a
revolution of the crank shaft, and then again released by the gear when the spring
is in tension, the result will be that the reciprocations of the igniting slide will be
of a very rapid order, alternating at the end traverse with a period of rest.
second hole inay be made through the slide bar through which the flame may
freely burn, when the flame pocket before mentioned is opposite the ignition port
during each of these periods of rest.
A
The rapid traverse of this slide may also be effected by a cain giving an alternate
quick and slow movement or a rapid movement alternating with a period of rest,
or where the engine is moving with sufficient speed the traverse of the flame may be
effected sufficiently quickly by means of the traverse, of an eccentric without the
intervention of springs at all.
Although the ignition of only one end of the cylinder has been described, it is
obvious that the ignition slide may be made double ended (two separate flames if
desirable being used) so as to carry flaine in opposite directions to the ignition ports,
one of which will be formed at each end of the cylinder, and thus the ignition of
the charges at these two ends may be effected by the same mechanism.
When an eccentric, crank, or cam is used partaking of the movement of the
crank shaft for actuating the ignition slide, it being desirable to iguite the charge
of combustible gas within the cylinder shortly after the piston has begun its stroke,
it is evident that such eccentric, crank, or cam may require to be set in a different
position for the backward and forward motions of the engine. This end might be
attained by means of a pair of eccentrics and link inotion. When however
arrangements are inade in a pair of reversing engines to actuate the igniting gear
by hand for starting the engine in either direction, as subsequently described, the
eccentric, crank, or cam driving the igniting slide may be left free to partly turn

page_text: round, the shaft from its backward to its forward position, a stop being formed at
each of them which shall, meeting a corresponding stop upon the eccentric, crank,
or cam drive it with a steady motion although it were keyed upon the shaft, the
backward motion of the engine driving it upon its backward centre, and the
forward motion of the engine driving it upon its forward centre. When however 5
the engine is stopped and reversed, the eccentric, crank, or cam will slide freely
round the shaft until it reaches the new position corresponding with the reversed
motion of the engine, so as to carry on the ignitions of the charges at the periods
required.
Arrangements may be made for adjusting the period of ignition and cut off 1
by adjusting the working positions of the eccentric, crank, or cam upon the shaft
so, as to make this period later or earlier, as desired, or where a spring traverse
is employed, the rod may be fitted with suitable adjustable gear for making it
unloose the catch which holds the slide later or earlier; as desired.
'As when the engine has to be started the igniting gear will not be in motion, 1
I attach hand levers or other suitable appliances to it by means of which the
ignition may be effected after the charge is admitted by means of the main slide
valve by working the igniting gear by hand, the motion of the said gear being of
course continued by the engine after the latter is started.
By means of the above described arrangement of engines and valves I therefore
obtain a direct acting reversing engine' capable of starting under load at any point
in the revolution of the crank shaft, such being the characteristic functions
required of an engine in tramway, locomotive, hauling, hoisting, and other similar
work. I may however where my engines are required to work nearly continuously
and in one direction as in ordinary engines or launch engines, employ the above 2
arrangement of cylinder and valves as a single cylinder engine, either double or
single acting and without reversing gear.
To keep the cylinders from overheating I may either inject water to the inner
surface of the cylinder through a hollow piston rod, by which means the lubricant
may also be injected, or I may use the usual water jacket where its weight is no 3
objection. When injecting the water through the piston rod a small force pump
may be used forcing the water into a closed annular water space surrounding
the piston rod, and external to the cylinders and not less in length than
their stroke, or thereabouts. A hole is drilled into the piston rod from the
outside into the hole down its centre, so as form together with the latter a 3
continuous channel for water entering the cylinder. This hole emerging upon
the surface of the piston rod is so positioned as to reciprocate wholly within
the water glands, so that any water forced into them may at all times have
free ingress to the cylinder through it. The air pump may be cooled by the
same means or by a water jacket. If cooled by injection through the piston 4
rod, this piston rod being as will be usual common to both the air pump and
working cylinder, the hole bored in the piston, rod may be sufficiently extended
to reach from the one piston to the other, a partition being made at about the
centre of the water glands by a suitable plug dividing the boring into two
tubes, one terminating at the surface in a hole at right angles to the axis of the 4
rod, and communicating with its surface at the centre of each piston. Similar
inlet holes may be made to communicate with the surface of the rods at either side
of the dividing plug at or about the centre of the water glands. The regulation of
the total supply of water being delivered through these glands and rods may be
effected through a valve regulating the suction of the pumps. The relative 5
amounts of water and lubricant delivered to each cylinder may be controlled by a
properly arranged check (such as a flat spring ring clasping the rod and fixed so as
to partly cover one of the inlet holes) fixed upon the piston rods, and capable of
partially closing one or other of the inlet holes. To prevent a back flow of the
gases along these holes in the piston rods a check valve may be introduced at their 5
point of emergence at the centres of the respective pistons. The glands entering
the stuffing boxes in the ends of the air pump and working cylinders may have

page_text: pipes cast upon them, so that when the parts are together the pipes upon the glands
will telescope into one another, a sufficient clearance being allowed between the
external surface of the internal pipe, and the internal surface of the external pipe,
to adinit of an india rubber ring being rolled in between them so as to form a
water tight joint, and at the same time admit of the glands being drawn home into
their respective stuffing boxes without affecting the tightness of the joint. For the
sake of econonizing space, and getting the glands into their position easily, I
prefer to cast the flanges upon them in such a manner as to avoid the necessity of
screwing studs into the cylinders at all, the studs or bolts being common to and
entering the flanges of both glands, so that nuts placed between and screwed home
against the flanges on one or other of the glands may have the effect of thrusting
them apart, and so driving each tightly into its stuffing box. The fact that there
are no fixed studs projecting from the cylinders greatly facilitates the operation of
getting the glands into place. The piston rings may be arranged in any convenient
manner to effect at the same time an even distribution of water round the
skin of the cylinder, and a sufficient tightness of piston to resist leakage past it of
the gas.
The speed of the engine may be controlled in any one of several ways_suited to.
the various circumstances in which the engine is likely to be placed. It may be
controlled by hand, either by adjusting the ordinary links to give a decreased or
increased traverse to the main slide valve, so admitting a smaller or larger charge
of combustible gas to the cylinder at each stroke, or by a separate valve, partially
throttling the channel by which the gas enters the valves from the force pump or
receiver. This latter class of valve may be conveniently worked where otherwise
desirable by an ordinary speed governor such as is used for steam engines. Control
of the speed of engine may also be obtained by connecting an ordinary speed
governor, such as described above, by suitable gear with the igniting slide, so as
to give an earlier or later ignition, and consequently an earlier or later cut off,
with a decreased or increased average pressure of the heated gases against the
piston throughout the length of its traverse.
It may sometimes be found convenient to employ four single acting cylinders acting
upon two cranks at right angles to one another, or three single acting cylinders
acting upon three separate cranks at angles of 120° with each other, or the four or
three cylinders may be placed at equal angular distances from each other around the
saine crank, as is the case in the " Brotherhood" and other similar engines. In
each of these cases, however, I so arrange the main slide valves that they are able.
to adimit a charge of gas to any one of the pistons during not less than its fair
proportion of the crank traverse, that is to say, in the case of each piston for not
less than 90° of crank traverse where four cylinders are employed, and for not less
than 120° of crank traverse where only three cylinders are employed, the ignition
and cut off in each case being arranged upon the principle described in an earlier
paragraph of this Specification.
Where otherwise convenient (as in the caso where a pair of double acting
cylinders working cranks at right angles are employed, and also in many other.
cases), I prefer to work the piston or pistons of the air and gas compressing pump
or pumps from and upon the piston rod of one of the working cylinders. This
puinp is not required to compress the air to the highest pressure used in the
operation of the entire arrangement, as the pressure is subsequently increased by
combustion within a closed chamber, and may be consequently very moderate, say
from 10 to 40 lbs. on the square inch. It is, however, convenient to have the
combustible mixture compressed to some extent prior to ignition, first, because
were it not so treated it would be difficult in starting the engine and working the
same to introduce a charge or charges into one of the cylinders, they being already..
filled, or partly so, with burnt gases at the pressure of the atmosphere; and,
secondly, because the combustible mixture burns more freely when compressed..
Compressing also renders it easy to store a reserve of the combustible mixture so
as to enable the engine to be restarted when standing direct from the valve, gear,

page_text: by admitting a charge from this reserve of gas at pressure to one or other of the
cylinders, and then igniting the same.
The reserve of combustible gas at pressure above mentioned may be stored in a
separate receiver provided with a stop valve to completely shut it off from the
rest of the arrangement when the engine is standing for any length of time. This
receiver may, in the case of stationary engines, be formed in and form a part of
the bed plate. In other cases it inay be conveniently formed as a wrought iron or
steel tube quite separate from the structure of the engines and their framing, or
fixed upon them as desired.
The mixture of the gases I prefer to obtain prior to compressing them, and for
this purpose may use a slide valve with two apertures at each end of the pumping
cylinder, the one for the admission of air and the other for the admission of gas.
The slide valve is held down to its face by bolts, nuts, and preferably rubber
springs. Where the pump is double acting the respective ports formed in the cover
at each end for the admission of air and gas are connected by a passage cast in the
cover, that for air terminating in a single aperture for the admission of the air from
the atmosphere, and fitted with a check valve to prevent the back flow of the air
and gas, and the passage for gas terminating in a single aperture for the admission
of the same fitted with a cock for regulating its amount, and connected by a gas
pipe with either the gas main (if the engine is stationary, or nearly so, as in crane
engines), or gas receiver (if the engine is being used for tramway, road engine, or
other locomotive or floating purposes.
To control the pressure in the air and gas receiver and prevent it rising above
that which is safe when the amount of combustible mixture being delivered by the
pump is greater than that being consumed by the engine I provide for throttling
the suction valves of the compressor by means of an expansive metal envelope. To
effect this purpose I fix a pair of thin steel discs together by their edges, and admit
the gas through a pipe from the receiver in between them in such a manner that
the pressure of the gas shall tend to part the discs while the gas tight joint at their
edges resist this tendency. The plates are corrugated in annular rings in a
similar manner to that of some pressure gauges, tho corrugation being formed in
the plates when hot between a pair of properly shaped stamps adapted to this
purpose, these corrugations admitting of a slight extension of the plate when sub-
jected to pressure between the edges and their centres, that is, in the lengths of
their radii. The plates are put together in pairs, but more than one pair may be
used where a considerable amount of total extension is desired to be obtained. When
the plates have a diameter of twelve inches it has been found to be desirable to form
thein of spring steel of less than 32nd of an inch thick. At the centre of these plates
where the extension will be greatest a rod or lever is attached, and by suitable
gear connected with a throttle valve either oscillating upon a centre or reciprocating
upon a face, controlling the gas and air supply to the compressing pump so that
when the pressure in the receiver has reached a certain fixed point deeined most
desirable in that particular arrangement of engine the amount of combustible
mixture being delivered to it and the engines from the pumps may be reduced by
the throttling action of the valve described. As it is often desirable so to form
this expander that up to a certain pressure in the receiver no movement shall take
place, but that on the pressure rising above this point it may communicate to the
expander a rapid extension so that this expander may form a sensitive governor,
controlling the gas and air supply, I attach a spring to it which holds the centres
firmly back against a properly arranged stop until the pressure has reached the
point desired. If the plates are so formed as to be exceedingly elastic, and the
spring so formed that its resistance does not increase rapidly with any further
extension or compression, an arrangement of parts may thus be produced of an
exceedingly sensitive character, and having no stuffing boxes or piston joints to
give trouble with their ever varying friction and frequent leakage. These expanders
inay in some cases be fitted with a scale marked with pressure in lbs., &c., so as to
act the double part of a pressure governor and a pressure gauge.

page_text: A spring expander may also be formed by a bent tube on the principle of a
Bourdan gauge, but for most purposes I prefer the former arrangement, as it is less
subject to vibration and derangement, and generally stiffer against external
shocks.
In order to limit the clearance spaces as much as possible I prefer to bring my
exhaust ports straight out from each end of the working cylinder to the slide valve
face or faces, either lengthening the valve so as to extend from end to end of the
cylinder (where the latter is double acting), and employing two separate slide valves
joined to the slide rod for the purpose. The valve is so formed that these ports are
never opened except to the exhaust passages, the "lap" on the valve being sufficient
to keep it always closed against the ingress of combustible gas to the cylinder.
The inlet port in the cylinder, which is formed either beyond the exhaust port or
in some other convenient position, and which is provided with a check valve, as
described, to prevent the back flow of the gases when their pressure has been
increased within the cylinder by combustion, is similarly always covered by the
slide valve, except during the full period of admission of gas, and the said valve is
so formed as never to open this inlet port to the exhaust passages.
The tendency
of the slide valve to rise off the face when the combustion of the gases within the
cylinder has set up a preponderating back pressure may be counteracted by suitable
springs on the back of the valve, which together with the pressure of the unconsumed
gases (if the valve is so arranged that they assist towards keeping it home against
its face) may be made sufficient to prevent this tendency taking effect. I do not
however in any way confine myself to using main slide valves enclosed within gas
tight valve chests, as is the usual practice in steam engines, such valve chests (or
steam chests) being filled with gas at the pressure of the delivery from the com-
pressing pump, and from which valve chest or chests the opening of the admission
port or passage would admit the combustible gaseous mixture to the cylinder; but,
on the contrary, I may prefer to employ a valve the face of which only is exposed
to the gaseous pressure, the gas pipe from the pumps and receiver terminating in
an aperture in the slide face of the cylinder, the position of which aperture may be
either beyond or at the side of the inlet port, and which will be connected during
the induction period with the inlet port of the cylinder by means of a channel in
the slide valve face in much the same manner as that in which the exhaust passages
are connected during the eduction period. Upon this plan the same relations of
lap and other parts may be retained as in the more ordinary form of slide valvo
used in steam engines, where the back of the valve is wholly exposed to steam
pressure. This formn of valve must however be pressed home against its face by
artificial means, such as springs upon the plate pressing against the back of the
valve.
I may mention in reference to the use of a self acting check valve to prevent the
back flow of the gases through the inlet port after combustion, and before cut off
by the main slide valve, that before the gas in the cylinder has expanded down to
a lower pressure than that of the unburned gases behind the check valve, the main
slide valve will have closed so as to admit of no further escape of gas into the
cylinder.
The main slide valve hereinbefore described may where desirable be given a
rocking or revolving traverse instead of the more common reciprocation in a
straight line, the parts being so arranged that it distributes the gases as herein-
before described.
Where it is desirable to jacket a cylinder with water, and where lightness is of
importance, I prefer to form this jacket with some malleable metal which admits
of being used in very thin sheets, such as steel, wrought iron, brass, or copper. By
this means the jacket may be made to take the place of an ordinary ornamental
covering or "cleading," as it admits of the use of polished brass, copper, or steel.
The joints can be made in any usual or convenient way.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Joseph John Butcher in the Great Seal Patent Office on the
27th April 1880.
JOSEPH JOHN BUTCHER, of Gateshead, in the County of Durham, Engineer
* IMPROVEMENTS IN GAS MOTOR ENGINES."
My Invention consists of improvements in gas motor engines, that is to say.
engines in which the impulse given to the piston or pistons is chiefly due to the
expansive force developed in the gases that result from a process of combustion (the
constituents of which will usually be coal gas and atinospheric air), and their
object is chiefly to render possible the construction of reversing engines suitable for
tramway, locomotive, hoisting, hauling, and other similar purposes, as well as the
simpler types of stationary engines.
In carrying out my Invention I prefer to use a slide valve for the distribution of
the gases within the cylinders of such a character that it both effects the admission
and emission (or exhaustion) of the gases to and from the cylinders, separate passages
however being used in the cylinder for these operations, and a check or cut off
valve, either self acting (as a clack valve) or actuated by mechanism, but in either
case so arranged as to prevent the back flow of the gases and flame into the supply
passages when an increased pressure is set up within the cylinder by combustion
during the remainder of the time in which the main slide valve keeps the induction
(or supply) port open for the admission of the gas, this slide valve being so arranged
where the engines are intended for reversing engines as to enable the gas to bo
admitted to the cylinder during at least 90° of the crank traverse, so that when two
double acting or four single acting cylinders are employed, at whatever point in its
revolution the crank may be standing a charge of explosive or combustible gas may
be admitted by moving the slide valves from the reversing levers, behind one of
the pistons, in such manner that when its pressure is increased by combustion it
may, acting upon the piston, drive the crank forward in the direction desired.
Thus, coupled with the power given by an ordinary slide valve and reversing gear
as used in steam engines, of admitting a charge of combustible gas to the cylinders
at any point in the revolution of the crank shaft, so that it inay when ignited,
thrust the piston either forward or backward as desired; I obtain a point of
ignition and cut off" entirely under control, and which may be made either early
as required for regular work or late as may sometimes be desirable in starting the
engine when the piston requiring to be acted upon may be half way or even more
down its cylinder. The traveise of the main slide valve corresponding with the
forward and backward movement of the engine may be effected by two separate
eccentrics and rods, the one being set for forward motion and the other for backward
motion, and the rod ends may be connected by a link so as to enable the slide valve
spindle to be worked off either one or the other eccentric at will, thus effecting the
reversing of the engine as in ordinary link motion used for steam engines, or only
one eccentric may be used, this eccentric being itself revolved partially round the
shaft to its forward or backward centre by means of a spiral sleeve or similar
device, or the different movements of the slide corresponding with the reverse
movements of the engine may be effected by some other convenient means.
motion is, however, to be preferred for ordinary purposes. Thus, in any case I
obtain a valve so arranged that when the piston of one of the cylinders of a common
two cylinder reversing engine is at mid stroke (the other being on its dead centre)
a charge of combustible gas may be admitted to either side of it while the other
side is opened to the exhaust passages, the tendency of the gas to return through a
the inlet port when the pressure is increased within the cylinder by combustion.
being checked by a check or cut off valve as described.
"
Link
To effect the ignition of the gaseous charges within the cylinders I prefer to use

page_text: a separate slide valve, and in most cases to effect this ignition from a' permanent
gas jet outside the cylinder. When the "cut off" of the combustible gas is effected
by means of a valve worked nechanically the ignition of the gases within the
cylinder may be effected by the saine means: The operation of communicating
ignition from outside the cylinder into the charge of combustible gas (generally at
a pressure above that of the atmosphere) within it, inay be effected by any of the
means commonly in use in gas engines. It has, however, been found by experiment,
that a simple means of carrying a flame from the open atinosphere into an enclosed
chamber in the manner required is to rapidly shear off the conical body of an
ordinary flame leaving only the base to keep the jet alight due to the combustion
of a jet of carburetted hydrogen or other gas burning at its surfaces of contact with
the oxygen of the surrounding air. The fact that under these circumstances the
constituents of combustion are to a considerable extent separated from one another,
the luminous cone of flame enclosing within it a core of gas, and being sur-
rounded by an envelope of atmospheric air, renders this flame for an instant'
self supporting after it has been withdrawn into an enclosed space within
which it is cut off both from the source of its gas supply and from all the
atmospheric air except that portion which immediately surrounds it, combustion
being sustained until the unburned gas within the luminous cone is consumed.
Thus this flame may be momentarily, enclosed in a pocket from which all com-
munication with the atmosphere is shut off, and with which a communication may'
be safely made with the combustible charge within the cylinder so as to ignite it."
This operation may be effected mechanically in several ways. According to one of
these the gas jet outside the cylinder is allowed to burn freely through a hole in a
sliding bar, such hole being somewhat larger than the body of the flame so as to
enable it to contain a small reserve of air for the combustion of the core of gas'
after it has been shut off from all communication with the atmosphere. The lower
surface of this sliding bar is somewhat above the level of the nozzle from which the
gas jet springs, so that when the bar is actuated it shears off the body of the flame.
only leaving its root or lower part alight, and thus does not put it out altogether.
Immediately on shearing off the flame the bar is made to slide between a pair of
properly scraped surfaces making a completely air tight joint so as to effectually
shut in the hole within which the flame is being carried. As soon as the hole is
completely shut in, between these surfaces, and thus any escape of the
gas rendered
unlikely, the onward movement of the flaine carrying bar brings this flame pocket
into open communication with a hole or port in the cylinder through which contact
is effected between the combustible mixture of gas and air contained therein and
the flame in the pocket described, and thus ignition is effected. When the port in
the cylinder through which ignition is effected is liable' to contain foul air from the
last charged, such air, or rather incombustible gas, being partially compressed by
the ingress of the new charge of combustible mixture, means may be employed to
clear it and allow it to fill with a strong charge of the mixture of inflammable gas
described; this may be done by allowing a slight momentary escape of gas from
the port. The need of such escape may however be avoided either by allowing the
stream of combustible gas as it enters the cylinder to flow partially through this '
ignition port, or by providing in the face of the ignition slide described above-a
recess which shall face the ignition port in the cylinder at the time when, the
inrush of explosive gas takes place, so that by compression any remaining burnt
gases froin the last charge may be forced home into this recess, and will therefore,
when the slide moves forward to carry the flaine pocket towards this ignition port,
the recess before mentioned partaking of the movement of the slide, shall carry.
away with it the remaining foul air in the port, so clearing the same and allowing
it to fill with a strong charge of combustible gas..
"
"
The ignition' slide may be actuated either from any of the moving gear con-
veniently situated for the purpose, or from a separate crank, eccentric, or cam upon"
the main crank shaft. It is however necessary that its motion when' conveying the
flame shall be of a rapid character, so that combustion may be sustained during

page_text: the transit from the open air to a position opposite the ignition port. This rapid
movement may be obtained when the movement of the actuating gear is too slow
for the purpose, by means of a spring so arranged that it is first drawn into tension
by the said gear, which latter, by then releasing a catch, allows the igniting slide
to rapidly follow it, carrying the flame pocket and flame forward with a springing
motion towards the igniting port. If the spring catch is now made to hold the
bar in this position until the gear moves backward through half a revolution of
the crank shaft, and then again released by the gear when the spring is in tension,
the result will be that the reciprocations of the igniting slide will be of a very
rapid order, alternating at the end traverse with a period of rest. A second hole
may be made through the slide bar through which the flame may freely burn
when the flame pocket before mentioned is opposite the ignition port during each
of these periods of rest.
The rapid traverse of this slide may also be effected by a cam giving an alternate
quick and slow movement, or a rapid movement alternating with a period of rest,
or where the engine is moving with sufficient speed the traverse of the flame may
be effected sufficiently quickly by means of the traverse of an eccentric without the
intervention of springs at all.
Although the ignition of only one end of the cylinder has been described it is
obvious that the ignition slide may be made double ended (two separate flames if
desirable being used) so as to carry flame in opposite directions to the ignition
ports, one of which will be formed at each end of the cylinder, and thus the
ignition of the charges at these two ends may be effected by the same mechanism.
When an eccentric, crank, or cam is used partaking of the movement of the
crank shaft for actuating the ignition slide, it being desirable to ignite the charge
of combustible gas within the cylinder shortly after the piston has begun its stroke,
it is evident that such eccentric, crank, or cam may require to be set in a different
position for the backward and forward motions of the engine; this end might be
attained by means of a pair of eccentrics and link motion. When however
arrangements are made in a pair of reversing engines to actuate the igniting gear
by hand for starting the engine in either direction, as subsequently described, the
eccentric, crank, or cam driving the igniting slide may be left free to partly turn
round the shaft from its backward to its forward position, a stop being formed at
each of them which shall, meeting a corresponding stop upon the eccentric, crank,
or cam, drive it with a steady motion although it were keyed upon the shaft, the
backward motion of the engine driving it upon its backward centre and the
forward motion of the engine driving it upon its forward centre. When however
the engine is stopped and reversed the eccentric, crank, or can will slide freely
round the shaft until it reaches the new position corresponding with the reversed
motion of the engine so as to carry on the ignitions of the charges at the periods
required.
Arrangements may be made for adjusting the period of ignition and cut off by
adjusting the working positions of the eccentric, crank, or cam upon the shaft so as
to make this period later or earlier as desired; or where a spring traverse is
employed the rod may be fitted with suitable adjustable gear for making it unloose
the catch which holds the slide later or earlier as desired.
As when the engine has to be started the igniting gear will not be in motion I
attach hand levers or other suitable appliances to it, by means of which the ignition
may be effected after the charge is admitted by means of the main slide valve by
working the igniting gear by hand, the motion of the said gear being of course
continued by the engine after the latter is started.
By means of the above described arrangement of engines and valves I therefore
obtain a direct acting reversing engine capable of starting under load at any point
in the revolution of the crank shaft, such being the characteristic functions required
of an engine in tramway, locomotive, hauling, hoisting, and other similar work. I
may however where ny engines are required to work nearly continuously and in
one direction, as in ordinary engines or launch engines, employ the above arrange-

page_text: ment of cylinder and valves as a single cylinder engine, either double or single
acting and without reversing gear.
To keep the cylinders from overheating I may either inject water to the inner
surface of the cylinder through a hollow piston rod, by which incans the lubricant
may also be injected; or I may use the usual water jacket where its weight is no
objection. When injecting the water through the piston rod a small force pump
may be used, forcing the water into a closed annular water space surrounding the
piston rod and external to the cylinders, and not less in length than their stroke,
or thereabouts. A hole is drilled into the piston rod from the outside into the hole
down its centre so as to form together with the latter a continuous channel for
water entering the cylinder. This hole emerging upon the surface of the piston rod
is so positioned as to reciprocate wholly within the water glands, so that any water
forced into them may at all times have free ingress to the cylinder through it. The
air pump may be cooled by the saine means or by a water jacket. If (cooled by
injection through the piston rod, this piston rod being, as will be usual, common to
both the air pump and working cylinder, the hole bored in the piston rod may be
sufficiently extended to reach from one piston to the other, a partition being made
at about the centre of the water glands by a suitable plug dividing the boring into
two tubes, one terminating at the surface in a hole at right angles to the axis of the
rod, and communicating with its surface at the centre of each piston. Similar inlet
holes may be made to communicate with the surface of the rods at either side of
the dividing plug at or about the centre of the water glands. The regulation of
the total supply of water being delivered through these glands and rods may be
effected through a valve regulating the suction of the pumps. The relative
amounts of water and lubricant delivered to each cylinder may be controlled by a
properly arranged check (such as a flat spring ring clasping the rod and fixed so as
to partly cover one of the inlet holes) fixed upon the piston rods and capable of
partially closing one or other of the inlet holes. To prevent a back flow of the
gases along these holes in the piston rods a check valve may be introduced at their
point of emergence at the centres of the respective pistons. The glands entering
the stuffing boxes in the ends of the air pump and working cylinders may have
pipes cast upon them, so that when the parts are together the pipes upon the glands
will telescope into one another, a sufficient clearance being allowed between tho
external surface of the internal pipe and the internal surface of the external pipe
to admit of an india rubber ring being rolled in between them so as to form a
watertight joint, and at the same time admit of the glands being drawn home into
their respective stuffing boxes without affecting the tightness of the joint. For the
sake of economizing space and getting the glands into their position easily I prefer
to cast the flanges upon them in such a manner as to avoid the necessity of screwing
studs into the cylinders at all, the studs or bolts being common to and entering the
flanges of both glands, so that nuts placed between and screwed home against the
flanges on one or other of the glands may have the effect of thrusting then apart,
and so driving each tightly into its stuffing box. The fact that there are no fixed
studs projecting from the cylinders greatly facilitates the operation of getting the
glands into place. The piston rings may be arranged in any convenient manner to
effect at the same time an even distribution of water round the skin of the cylinder
and a sufficient tightness of piston to resist leakage past it of the gas.
The speed of the engine may be controlled in any one of several ways suited to
the various circumstances in which the engine is likely to be placed. It may be
controlled by hand, either by adjusting the ordinary links to give a decreased or
increased traverse to the main slide valve, so admitting a smaller or larger charge
of combustible gas to the cylinder at each stroke, or by a separate valve partially
throttling the channel by which the gas enters the valves from the force pump or
receiver. This latter class of valve may be conveniently worked where otherwise
desirable by an ordinary speed governor, such as is used for steam engines.
Control of the speed of the engine may also be obtained by connecting an ordinary
speed governor, such as is described above, by suitable gear with the igniting slide,

page_text: so as to give an earlier or later ignition, and consequently an earlier or later cut off,
with a decreased or increased average pressure of the heated gases against the
piston throughout the length of its traverse.
It may sometimes be found convenient to employ four single acting cylinders
acting upon two cranks at right angles to one another, or three single acting cylinders
acting upon three separate cranks at angles of 120° with each other, or the four or
three cylinders may be placed at equal angular distances from each other around the
same crank, as is the case in the "Brotherhood" and other similar engines. In
each of these cases however I so arrange the main slide valves that they are able
to admit a charge of gas to any one of the pistons during not less than its fair
proportion of the crank traverse, that is to say, in the case of each piston for not
less than 90° of crank traverse where four cylinders are employed, and for not less
than 120° of crank traverse where only three cylinders are employed, the ignition and
cut off in each case being arranged upon the principle described in an earlier
paragraph of this Specification. Where otherwise convenient (as in the case where
a pair of double acting cylinders working cranks at right angles are employed, and
also in many other cases) I prefer to work the piston or pistons of the air and gas
compressing pump or pumps from and upon the piston rod of one of the working
cylinders. This pump is not required to compress the air to the highest pressure
used in the operation of the entire arrangement, as the pressure is subsequently
increased by combustion within a closed chamber, and may be consequently very
moderate, say from 10 to 40 lbs on the square inch. It is, however, convenient to
have the combustible mixture compressed to some extent prior to ignition, first,
because were it not so treated it would be difficult in starting the engine and
working the same to introduce a charge or charges into one of the cylinders, they
being already filled or partly so with burnt gases at the pressure of the atmo-
sphere; and secondly, because the combustible mixture burns more freely when
compressed. Compressing also renders it easy to store a reserve of the combustible
mixture, so as to enable the engine to be restarted when standing direct from the
valve gear by adınitting a charge from this reserve of gas at pressure to one or
other of the cylinders and then igniting the same.
The reserve of combustible gas at pressure above mentioned may be stored in a
separate receiver provided with a stop valve to completely shut it off from the
rest of the arrangement when the engine is standing for any length of time. This
receiver may in the case of stationary engines be formed in and form a part of the
bed plate. In other cases it may be conveniently formed as a wrought iron or
steel tube quite separate from the structure of the engines and their framing, or
fixed upon them as desired.
The inixture of the gases I prefer to obtain prior to compressing them (except
where the original pressure of the coal gas or the lesser constituent of combustion
is equal to or greater than that required for the compressed combustible mixture,
as it might be when stored at pressure for locomotive and other purposes), and for
this purpose may use a slide valve with 2 apertures at each end of the pumping
cylinder, the one for the admission of air, and the other for the admission of gas.
The slide. valve is held down to its face by bolts, nuts, and preferably rubber
springs. Where the pump is double acting the respective ports formed in the
cover at each end for the admission of air and gas are connected by a passage cast
in the cover, that for air terminating in a single aperture for the admission of the
air from the atmosphere, and fitted with a check valve to prevent the back flow of
the air and gas, and the passage for gas terminating in a single aperture for the
admission of the same fitted with a cock for regulating its amount, and connected
by a gas pipe with either the gas main (if the engine is stationary or nearly so, as
in crane engines) or gas receiver (if the engine is being used for tramway, road
engine, or other locomotive or floating purposes).
To control the pressure in the air and gas receiver, and prevent it rising above
that which is safe when the the amount of the combustible mixture being delivered
by the pump is greater than that being consumed by the engine, I provide for

page_text: throttling the suction valves of the compressor by means of an expansive metal
envelope. To effect this purpose I fix a pair of thin steel discs together by their
edges, and admit the gas through a pipe from the receiver in between them in
such a manner that the pressure of the gas shall tend to part the discs while the
gas tight joint at their edges resists this tendency. The plates are corrugated in
annular rings in a similar.manner to that of some pressure gauges, the corrugations
being formed in the plates when hot between a pair of properly shaped stamps
adapted to this purpose; these corrugations admitting of a slight extension of the
plate when subjected to pressure between the edges and their centres, that is, in the
lengths of their radii. The plates are put together in pairs, but more than one
pair may be used where a considerable amount of total extension is desired to be
obtained. When the plates have a diameter of 12 inches it has been found to be
desirable to form them of spring steel of less than 2d of an inch thick. At the
centro of these plates where the extension will be greatest a rod or lever is attached,
and by suitable gear connected with a throttle valve either oscillating upon a centre
or reciprocating upon a face controlling the gas and air supply to the compressing
pump, so that when the pressure in the receiver has reached a certain fixed point
deemed most desirable in that particular arrangement of engine, the amount of
combustible mixture being delivered to it and the engines from the pumps may be
reduced by the throtting action of the valve described. As it is often desirable
so to form this expander that up to a certain pressure in the receiver no movement
shall take place, but that on the pressure rising above this point. it may com-
municate to the expander a rapid extension, so that this expander may form a
sensitive governor controlling the gas and air supply, I attach a spring to it which
holds the centres firmly back against a properly arranged stop until the pressure
has reached the point desired... If. the plates are so formed as to be exceedingly.
elastic, and the spring so formed that its resistance does not increase rapidly with
any further extension or · compression, an arrangement of parts may thus be
produced of an exceedingly sensitive character, and having, no stuffing boxes or
piston joints to give trouble, with their. ever varying friction and frequent leakage.
These expanders may in some cases be fitted with a scale marked with the pressure
in lbs., &c., so as to act the double part of a pressure governor and a pressure gauge.
A. spring expander may also be formed by a bent, tube on the principle of a
Bourdon gauge; but for most purposes I prefer the formner arrangement, as it is
less subject to vibration and derangement, and generally stiffer against external
shocks.
:
"
In order to limit the clearance spaces as much as possible, I prefer to bring my
exhaust ports straight out from each end of the working cylinder to the slide valve
face or faces, either lengthening the valve so as to extend from end to end of the
cylinder (where the latter is double acting), and employing two separate slide
valves joined to the slide rod for the purpose. The valve is so formed that these
ports are never opened except to the exhaust passages, "the lap" on the valve
being sufficient to keep it always.closed against the ingress of combustible gas to
the cylinder. The inlet port in the cylinder, which is formed either beyond the
exhaust port or in some other convenient position, and which is provided with a
check valve, as described, to prevent the back flow of the gases when their pressure
has been increased within the cylinder by combustion, is similarly always covered
by the slide valve, except during the full period of admission of gas, and the: said
valve is so formed as never to open this inlet port to the exhaust passages. The
tendency of the slide valve to rise off the face when the combustion of the gases
within the cylinder has set up a preponderating back pressure may be counteracted
by suitable springs on the back of the valve, which, together with the pressure of
the unconsumed gases (if the valve is so arranged that they assist towards keeping
it home against its face), may be made sufficient to prevent this tendency taking
effect; I do not however in any way confine myself to using main slide valves
enclosed within gas tight valve chests, as is the usual practice in steam engines,
such valve chests (or steam chests) being filled with gas at the pressure of the

page_text: delivery from the compressing pump, and from which valve chest or chests the
opening of the admission port or passage would admit the combustible gaseous
mixture to the cylinder; but on the contrary I may prefer to employ a valve, the
face of which only is exposed to the gaseous pressure, the gas pipe from the pumps
and receiver terminating in an aperture in the slide face of the cylinder, the
position of which aperture may be either beyond or at the side of the inlet port,
and which will be connected during the induction period with the inlet port of the
cylinder by means of a channel in the slide valve face in much the same manner as
that in which the exhaust passages are connected during the eduction period.
Upon this plan the same relations of lap and other parts may be retained, as in
the more ordinary form of slide valve used in steam engines, where the back of the
valve is wholly exposed to steam pressure. This form of valve must however be
pressed home against its face by artificial means, such as springs upon the plate
pressing against the back of the valve.
I may mention in reference to the use of a self acting check valve to prevent the
back flow of the gases through the inlet port after combustion, and before cut off
by the main slide valve, that before the gas in the cylinder has expanded down to
a lower pressure than that of the unburned gases behind the check valve, the main
slide valve will have closed so as to admit of no further escape of gas into the
cylinder.
The main slide valve hereinbefore described may where desirable be given a
rocking or revolving traverse instead of the more common reciprocation in a
straight line, the parts being so arranged that it distributes the gases, as herein-
before described.
Where it is desirable to jacket a cylinder with water, and where lightness is of
importance, I prefer to form this jacket with some malleable metal, which admits of
being used in very thin sheets, such as steel, wrought iron, brass, or copper. By
this means the jacket may be made to take the place of an ordinary ornamental
covering or "cleading," as it admits of the use of polished brass, copper, or steel.
The joints can be made in any usual or convenient way.
As when starting these engines it is desirable for them to have as little inert
resistance as possible to overcome until they have attained some speed, any ordinary
means may be provided to make them take up their load gradually when starting
is being effected.
The accompanying Drawings illustrate my improvements. Figures 1, 2, 3, and 4,
Sheet 1, are respectively horizontal section, vertical section, and back and front end
elevations of the head of a cylinder with valves, as herein before described. A is
the exhaust passage; A', the exhaust passage in the slide valve B; A2, the
exhaust outlet from the casting emerging at A³; corresponding letters indicating
similar parts on the various Figures; B₁ is the supply port in the cylinder casting,
which is connected by a suitable pipe with the compressing pump, and the arrows
in the Figure shew the direction of the gas admitted when the passage B² comes
opposite B through B, and thence through the back pressure valve B' and passage
B to the interior of the cylinder. The sequence of conditions which occur when
this valve is driven backwards and forwards over the valve face by its eccentric is
very similar to that of an ordinary simple steam slide valve, except that the
admission port B2 is cast in the valve and doubled backwards to meet B₁, so as to
avoid the necessity of a gas tight chest, such as that shewn in Figures 26 and 27,
Sheet 2. The slide B is kept upon its seat by means of the springs C held in
position by the nut C¹ and stud; C2 is a cover with milled head, which when the
spring (rubber, as shewn) is tightened down sufficiently to resist the back pressure
of the gas is screwed on to the end of the stud by hand, so as to cover the spring
and also form a rigid check to prevent the valve rising off its seat when
experiencing any sudden shock sufficient to overcome the resistance of the spring;
D, D, are the bolt or stud holes for attaching the casting to the cylinder, which may
be either double or single acting, and E is the jacket cast in this case with the
cylinder through which the cooling fluid flows; F is the ignition valve; and F¹,

page_text: the flame carrying pocket, so arranged as to convey a pocket of flame from the
permanent flame F to the opening in the cylinder head F. Iminediately the
gases are ignited within the cylinder, the pressure set up beyond the pressure of
compression with which the gas is entering it forces down the check valve B into
its seat, and so effects the automatic cut off of the gases, as hereinbefore described.
It is obvious that in any of the arrangements of cylinders mentioned as constituting
the parts of a reversing engine, the various slide valves B may be driven by either
of a pair of eccentrics coupled by a link in the usual way (as shewn in Figure 6) ;.
they may by means of the reversing levers actuating the link be placed in a
position, such that whatever the position of the crank shaft at the time they will
admit gas at pressure from the reserve kept for that purpose, so as to act upon one
or more of the pistons, and thus tend to start the engine either forward or back-
ward, as desired. If now the ignition valves F (driven by the shaft F and cam F5,
against the face of which they are always held by the tension of the spring Fe) bo
actuated by means of the hand gear for turning the shaft F partly or wholly
round upon its axis, the various springs will alternately draw the flame pockets F
opposite the various ignition ports F³, until the gas that has been supplied to one
of the cylinders by the slide valves B is ignited, and drives the engine in the
direction desired. The method of reversing the motion of the ignition valves F
when they are picked up by their driving gear after the starting of the engine is
represented in other Figures of the Drawings, and hereinafter described. The
distributing valve b¹, Figure 6, is shown at a higher level than b, this being
desirable, as at the end of the cylinder through which the piston rod passes the.
ignition slide and check valve, with their ports and passages, have to be raised
sufficiently to clear the stuffing box, water glands, &c., which surround the said.
piston rod; Figure 5 is a plan shewing the ports, &c., on the top of the cylinder
head marked with letters corresponding with those in Figures 1 to 4; B is a
stopper and gland covering the check valve B of Figure 1 so as to prevent it
rising, and enable its seat to be machined out; Figure 16 (Sheet 2) shows the
position of the ignition valve F when raised clear of the piston rod and glands.
Figure 7 shews a back pressure valve, so arranged that. it is supplying its own
gas to the cylinder when allowed to do so by the driving gear, and also to act
as a check valve immediately the gas is ignited within the cylinder, thus avoiding
unnecessary friction, which in some cases may be desirable. A is the check valve
having a low lift and wide beating seat, to which the spindle A¹ is attached
passing down through the stuffing box B or its equivalent to the nut and cup C.
Upon the lower lip C¹ of the cup a spiral spring D presses, the tension of which
can be adjusted by means of the nut shewn, so as to rather more than balance the
lifting power of the gases beneath the valve A entering from the compressing
cylinder or cylinders. Thus, when the spring D is acting against the valve, the
latter is arranged upon the plan of an ordinary safety valve. If now any lifting
gear (such as the lever E driven from the shaft E' by the arm E²) be applied
beneath the stop C2, so as to lift the said cup together with the spring pressing
upon it clear of the nut upon the valve spindle A', it is clear that the valve A
being now released from all downward tension will be lifted by the pressure of the
gases under it, which gases will thus escape through it and its passages F into the
cylinder, the valve remaining open until the inrush of combustible gas shall have
raised the pressure above the valve to an approximate equality with that below it,
when if no other force were applied it would drop naturally backward upon its seat.
If however at any time during the inrush of gas, and while the valve A is standing
clear of its seat, the gases within the cylinder are ignited, and an excess of pressure
in consequence developed above A, the valve will close as a back pressure valve
upon the same principle as the check or clack valve B*, Figures 1 to 5.
Figures 13, 14, and 15, Sheet 2, are respectively horizontal and vertical sections.
and end elevation of a class of gas cylinder geared with the valve last described.
In this case the reversing link A, driven by eccentrics as usual, actuates so as to.

page_text: J
drive the engine in either direction; the connecting rod A' through a block and pin
of the usual class. The connecting rod A¹ is attached through suitable pins to the
levers A, which actuate the counter shafts As and levers B and B so as alternately
to lift the exhaust valves. (which are shewn in this case of the ordinary lifting mitre
valve class), the springs C and C controlling the valves admitting and cutting off
the gas as arranged in Figure 7. The combustible gases entering the cylinder pass
the port D communicating with the ignition slide D, which is driven by the eccentric
rodrD actuated by an eccentric so arranged as to ignite the gases at the beginning,
of or early in the stroke. Such an eccentric, the reversal of which is effected auto-
matically, is shewn at Figures 21 and 22. It is partly loose upon the shaft.A so as
'to be free to move partly round the shaft into the positions desirable for its forward
and back ward gear. B is a segmental stop cast upon the eccentric, and B a seginental.
stop cast upon a collar C keyed onto the shaft. Thus the arrangement is, such that.
when the engine is started the shaft A is free to turn through the eccentric until
the stop B comes into gear with one side or other of the stop B'... When starting,
the engine. the. rod D may be detached by a gab from the pin joining it to the,
ignition valves, and the latter moved backwards and forward by a hand lever so, as,
to ignite the gases as desired, the gab being then dropped into position and actuating,
the valves from the eccentric as described. Where ignition valves are worked in.
this way by a simple eccentric without springing traverse, as at D, Figure 13, I
usually inake them travel rather beyond both the igniting jet port and the cylinder,
igniting port, so that the transfer of the flame when completely cut off from its
sources of supply within the flame pocket may be done as quickly as possible,
avoiding that slow portion of the stroke where the eccentric centre and shaft centres.
are both in line, or nearly so, with the valve travel.
}
Figure 26, Sheet 2, shows an arrangement of valves precisely similar in principle
to those shewn in Figure 1, but enclosed within a gas tight chest.
A is a wedge
shaped block, shewn at Figure 27, which can be adjusted by a screw passing through
it from the outside through the stuffing boxes, so as to keep the valve B from lifting.
when the back pressure due to internal compression is set up within the cylinder.
'is an elastic liner fitted into a recess above the wedge A; B' is the check valve,.
as before, and C the chimney within which the igniting flaine is fitted, the valve..
carrying which works. by. Imeans of an eccentric below the valves shown.
:
Figures 18, 19, and 20, shew an ignition valve and ports arranged on the principle
of shearing off the body of a gas flame and carrying the upper part of the cone.
between 2 gas tight faces into communication with the combustible mixture of gas
at pressure. A is the permanent jet burning through the hole turned as to form
a pocket; in the valve B, the chimney C ventilating the same; B' is a spare, pocket
in the valve which allows the flame to burn through it when the pocket B² is.
opposite the port D.. The valve B is wedge shaped, so that it may be adjusted 4
tightly, against its upper and lower gas tight faces D1 and D2 by means of the.
cover Ds and nuts and springs shewn. The valve is actuated upon the saine plan
as that shewn at F, Figures 1, 2, and 4. In Figure 19 this valve is shewn acting
as its own cut off valve, the distribution of the gases being effected by the slide
valve E. Figure 20 is a modification of this type of valve arranged to use with a
check valve, the pocket marked F being intended to carry away the remaining foul
air which might otherwise collect between it and the stream of fresh gas rushing
past it.
1
Figures 23, 24, and 25 shew an eccentric for driving valve gear arranged to take
up the various positions corresponding with the backward, forward, and neutral
positions of link notion gear by means of turning it round the driving shaft by,
the aid of a spiral sleeve and key way. A is a hand lever clutching the loose
collar B, which has a spiral key B tightly fixed in it, and entering the shaft at B
as a straight key. An extension of the eccentric C forms a sleeve.C with a spiral
slot in it, through which the key. B', passes before gearing into the shaft. If the
collar B be moved over the shaft, the key will turn the eccentric C round the

page_text: shaft by means of the spiral part of the key B¹, while it remains fixed with regard
to the said shaft in its angular position, being geared beneath the sleeve by a
straight key into the shaft.
'
Figures 16 and 17, Sheet 2, shew an arrangement of water gland previously
described; A, B, are the two glands pressed outwards by means of the studs and
nuts 6 into the respective stuffing boxes in the cylinder ends A and B. An
annular space is left between the ends of these two glands telescoping into one
another, within which the rubber rings C, C', are placed. When the packing in
the stuffing boxes is to be tightened up these rings roll over sufficiently to admit
of the free play of the glands. The whole arrangement forms a water space round
the piston rod, which can be made perfectly tight without any extra stuffing boxes
being used, so that water may be supplied through this annular space to the hole
emerging from the side of the piston rod in a similar position to that shewn in
Figure 13. At D is shewn in dotted lines the facing upon the outside of the
glands to which the supply pipe flange is attached. Figures 13 and 15 shew a
similar double stuffing box in a place where no second cylinder requires to be
packed; this arrangement may be considered from one point of view as a single
stuffing box with a long annular metallic distance piece between the back and
front parts of the packing. The distance piece marked P is a loose fit both outside
and in, and is pierced with holes so as not to interfere with the passage of the
water. A single gland P¹ forces the whole of the packing both before and behind
the distance piece home so as to make a pair of tight joints. The hole entering
the piston rod at right angles to its axis, and thence continuing along its axis and
upwards through the piston, is shewn in dotted lines, and the direction of the flow
of the water is indicated by arrows.
Figure 10) shews an arrangement in section for limiting the amount of compressed
gas and air by means of a slide controlled by the pressure of the gases, so as not
to allow the pressure to rise in the receiver above a fixed limit; P, P¹, are the
suction ports of a double acting compressor controlled by the slide valve V, the
ports in which come opposite the corresponding ports in the compressing cylinder
when the piston within it is moving in suction. The cover C, which is retained
firmly against its seat by suitable spring bolts or studs, not shewn, has ports C, C³,
cast in it opposite to the ports P, P, in the cylinder; the small slide valve S is so
placed upon the back of this cover that a slight longitudinal movement will close
the ports C, C. The rod S¹ is attached by suitable means to an expansive
envelope, such as is herein described, and so arranged that on the pressure in the
receiver reaching a certain maximum pressure judged best, any further increase in
such pressure will by distending the envelope act upon the rod S so as to move
the valve S across the face of the cover C, and thus partially or entirely close the
ports C and C, and any other corresponding ports. D is the divided gas way in
the cover,
and E the common port of supply.
Figures 11 and 12 are respectively a section and elevation of such an expander
formed essentially of a pair of flexible steel discs A, B, corrugated annularly, as
shewn, so as to allow of their radial extension. Their edges A', B', with a packing
ring between them are bolted together between a pair of rigid rings C, C₁, so as to
forn a perfectly air tight joint. Their centres are attached to the discs D, D, by
means of the bolts E, E, which have large heads e, e', on the inside of 'the plates,
so as to make it easy to form an air tight joint by means of a rubber (or other
suitable) packing ring surrounding the bolt, and pressed by the flat head against
the flexible plate. The discs D, D', are extended so as to receive a part of the
thrust of the flexible plates which they tend to support. The bolt E¹ is drilled so
as to form a way for the entrance of the gas and air, for which purpose a pipe may
be attached to the screwed end of the bolt E¹ by means of an ordinary pipe
coupling, and connected with the receiver within which the gas is stored if such is
being used. F is a bracket by means of which the expander may be attached to
a solid support through the disc D'; G is a lever attached through the centre G¹
to the fixed centre Fi, and at G2 pressing against the disc D. Thus the tension of

page_text: the spiral spring Gs (which can be controlled by the nut g and bolt g¹) tends.to
close the expander, which can be so regulated-a suitable spring being chosen-that
it will not lift the lever G against the pressure of the spring G³ until the desired
pressure in the receiver has been reached. Any subsequent movement is communi-
cated through the eye H to the throttling gear before described.
An alternative and simpler arrangement is shewn in Figures 8 and 9 for
preventing a too great influx of gas to the suction valves of the air pump. In this
case the result is obtained indirectly by preventing the complete closing of the
delivery valve, and so allowing the cylinder.to, partially choke itself with gas
returning to it on its backward stroke through them. In the Figures A is the
delivery valve, upon the top of which is an open slot or box (a) formed so as to
clasp the head of the bolt B. A space is left between the head of the bolt and the
top of the valve so as to allow of the latter lifting the bolt. head, forming a stop
for the same. The head of the bolt B is in this case formed of
separate collar
screwed and pinned onto it; above the collar the bolt passes through a guide C.
which is dropped into its seat C, and forms a. rigid stop to prevent the thrust of
the spring D forcing the bolt further down. A. solid washer or, collar B₁ formed
upon it presses through a packing ring upon the expander plate E, to which it is
attached by the nut and washer above. This latter washer is extended so as to
form a rigid dise to support and receive the pressure of the flexible plate E.. The
latter is rendered air-tight at its edges by being bolted down to the valve chest by
means of a rigid metal ring above and a packing ring below. The rigid ring G is
in this case continued upwards in the form of a cylinder, and screwed internally.
at its top G' so as to receive the stopper H, which enables the tension of the
spring D to be controlled at will. This tension is so arranged that it is wholly
received by the stop C until the compressed air above the valves reaches the
maximum pressure desired, any excess of pressure, however, lifting the bolt against
the pressure of the spring off the rigid stop C, and preventing the delivery valve A
from dropping. wholly back into its seat. Such an arrangement may be used
where from any causes a slide valve controlling the suction passages is
undesirable.
t
Figures 28, 29, and 30, Sheet 3, are respectively a horizontal section, a vertical
section, and a side view of the valve gear of an engine arranged upon the plan of
a separate ignition and cut off slide somewhat similar in design to that shewn in
Figures 18 and 19, but carrying its igniting flame in a different way, and so as to
avoid the necessity of a springing traverse. A is the main slide valve driven from
the reversing link A' in the customary way, as shewn, and at A2 is shown a slightly
flexible connection joining it to a second similar slide when in use for a double
acting engine. These connections are made of sheet iron thin enough to be slightly
flexible, with the view of allowing the valves to adjust themselves to slight
inequalities in the line of their faces; they are shewn wide enough to resist any
tendency to bend in the plane of the valve faces. The exhaust valve B is here
separated from the side, as the internal cut off and igniting slide would render it
inconvenient to make the required additional passages; its outlet to the exhaust
pipe is not shewn, but is in the centre at the top of the cylinder, or in any more
convenient position.
This exhaust slide is of the common mitre type, opening inwards, and B¹ is the
spindle, by pressure upon which the valve is opened through the air tight but
flexible plate shewn, which might have substituted for it a stuffing box if desirable.
The arm B upon the weigh bar B³ is actuated by the lever B4, which is joined by
the connecting rod B' with the valve A, and partakes of the motion given to it by
the reversing link A¹ The half throw of the slide valve A should in this case be
greater than the width of the opening e' added to the width of the opening c² in
the cut off, an ignition slide C, as otherwise this inner slide having a travel across
the face of the outer. slide, a through way may be made for the gases at a time
when it is not desirable, and a loss would be consequently caused. In other words,
when the link A' is mid gear, and the valve A standing in its middle position, no

page_text: amount of movement of the cut off valve C should make a through way for the
combustible gases from the port P into the cylinder. The arrows shew the direction
of flow of the combustible gases. The valve C is driven through the rod C', which
is actuated by an eccentric arranged upon the plan shewn in Figures 21 and 22,
and this eccentric is so adjusted upon the driving shaft that when the port c² is
passing the opening D into the cylinder, and consequently the ignition pocket E
is advancing with its burden of flame towards the opening D, the said eccentric is
giving the quickest longitudinal movement, for in cylinders of this class it is
very desirable that the admission of the combustible charge and its ignition
should be effected in a short a time as possible, and while the piston is just turning
the end of its stroke or thereabouts, thus necessitating comparatively ample port
openings and quick relative travel of valve. The distributing valve A is on the
other hand at or about the end of its stroke, and is consequently traveling most
slowly, the directions of travel at the period illustrated being indicated by the
dotted arrows. F' is the position of the perinanent igniting flame, which may be
communicated to D by the pocket E by any of the methods common in gas engines,
or the latter pocket may be arranged to shear off the head of a flaine entering
within it in a similar manner to that described in reference to Figures 18 and 19.
In starting an engine the distributing valves A are set to their forward or backward
position by means of the reversing link A', so that they will only supply com-
bustible charges to those cylinder ends that are in a position to actuate the crank
shaft in the direction desired, the operation so far being exactly similar to that of
starting an ordinary stean engine. The valves C are then passed backwards and
forwards beneath the distributing valves A, so as first to open a through way for
the gases wherever such is admitted of by the positions of the distributing valves,
and then to ignite the said gases, the perinanent jets F having of course been first
lighted, and the receiver for containing the reserve of combustible gases at pressure
(which is not drawn, as it may be of any shape and size most convenient for the
purpose in hand) filled. The driving stops then pick up and continuously actuate
the eccentric for the ignition slide C in either forward or backward gear upon a
plan similar to that shown in Figures 21 and 22, Sheet 2.
Figure 31 shews a simple method of effecting this movement by means of a
suitable hand lever carried upon the eccentric rod itself. A, Figure 31, is the
eccentric rod, and B is a continuation of the same, attached to it through the centre
pins C and D and bell crank lever E and E' in such a manner that when the
handle E is sprung into the clutching catch e, e', the rod B is fixed rigidly with
regard to the rod A, and consequently partakes of its reciprocal novemment, which
it communicates to the valve C, Figure 28. When however it is desired to traverse
the slide C by hand the handle E' is lifted out of its catch e, e', and worked up and
down so as to give notion to the valve C independently of the position of the
eccentric, which is intended for driving it so as to effect the admission and ignition
of the gases as described.
Figures 32 and 33 are respectively a vertical section and a plan of a simple
arrangement of governor gear for controlling the speed of the engine by diminishing
the influx of combustible gas to the motor cylinders when the speed rises too much,
the pressure of the gases being prevented from accumulating behind the valves, as
they would otherwise do, by any suitable arrangement of pressure governor, such as
those described in connection with Figures 8, 9, 10, 11, and 12. The shaft A,
Figure 33, which is driven in any suitable way with and by the engine, carries
upon it a fixed collar and its journals B, to which the pair of governor balls shewn
are attached, the spring C pressing the sliding sleeve D against the collar E until
the increasing motion of the governor balls has overcome its resistance, when the
sleeve is drawn towards the collar B. Upon this sleeve is a revolving rack D' gearing
into a segmental rack F (which arrangement night obviously be replaced by lever
gear) so that as the sleeve is drawn along the shaft by the motion of the governor
the rack F turns the spindle G and fanale screw G₁. The male screw H is turned
solid with the square block H', which prevents it from turning with the motion of

page_text: the spindle G, and it is thus thrust downwards so as to diminish the lift of the check
valve shewn (which may be the back pressure cut off valve before described, or an
independent valve). The spindle G is prevented from falling down through the
stuffing box I by means of the rack F supporting it upon the guide J, which also
prevents it from moving laterally. It is obvious that this governor acts the part
of and might in some instances be replaced by the ordinary throttle valve governor,
but in any case where the speed of the engine thus checks the influx of gases to
the motor cylinders a suitable governor must be provided to prevent the pressure
of the combustible gases delivered by the pumps rising above a safe or desirable
limit.
Figures 34, 35, and 36 are respectively a plan and view in elevation of the mitre
wheel clutch face and a section of the counter shaft and sleeve coupling of a counter-
shaft for driving the valve gear formerly described, so arranged that in whatever
direction the driving shaft A (which may be the crank shaft of the engine) is
revolving, the shaft Z is always driven in one uniform direction. B is a clutch
fixed angularly with regard to the shaft A and compelled to revolve with it by
means of the key a, but free to slide along it into gear with either of the loose
mitre wheels Cor D. When the driving shaft is revolving in the direction indicated
by the arrow at A the sliding clutch disengages automatically from the wheel D,
and is thrust by the inclined faces of the disengaging clutch and wheel along the
shaft and into gear with the opposite clutch and wheel C, which it causes to revolve
with the shaft, the wheel C turning the driven wheel E and countershaft Z in the
direction indicated by the arrow, and this wheel E in its turn driving the disengaged
wheel D over the driving shaft in a direction contrary to that shaft's motion. If
the direction of motion of the driving shaft be now reversed the sliding clutch B
disengages from the wheel C, and is forced by the inclined faces of its clutch back
along the shaft into gear with D, which it drives in a contrary direction, so as to
result in a motion of the driven wheel E in the same direction as before, the
wheel C now revolving loose upon the shaft. These wheels are bushed with brass
or bronze or other suitable metal, and prevented from running back out of gear by
suitable collars. F is a bearing supporting the counter shaft Z, which is shewn
coupled to the shaft G by a sleeve and spiral key and keyway, a straight key fixing
it angularly with regard to G. When it is desirable to partially revolve the shaft.
by hand so as to actuate the valves as before described, this sleeve is traversed along
the shaft by means of a suitable hand lever and clutch gearing into the annular
groove at H, the spiral key then revolving the coupling and with it the valve shaft
so as to ignite the gases as desired. With regard to the positions of the clutches cl
and d, upon the bevel wheel C and D they must be so arranged as to respectively
drive the shaft Z with the same period of motion with regard to the piston travel,
so that by whichever wheel C or D the countershaft is driven ignition, &c., will
take place at the right point in the stroke. Figure 37 shews a water gland in
which the stepped piston rod acts as its own feed pump. A is the suction valve,
and suitable delivery valves are fitted within the piston itself.
And having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim as my "Improvements in Gas
Motor Engines,"
First. Effecting an automatic cut off in such engines by a back pressure valve,
and also the ignition of the gases above the said valve, that is to say, after they
have passed the back pressure valve and are upon the cylinder side of it, through
an igniting port separate from the inlet port, all substantially as hereinbefore
described.
Second. The arrangement in such engines, in the manner hereinbefore described,
of valve gear regulating the distribution of the combustible gases so as to admit
them during a considerable portion of the stroke, combined with cut off gear for
totally enclosing the ignited charge within the cylinder at a very early period of
the stroke, as hereinbefore explained.
Third. Constructing reversing gas motor engines with link motion or similar

page_text: gear for distributing the combustible gases to the motor cylinders combined with
ignition by means of a separate valve, substantiaily as herein before described.
Fourth. Constructing reversing gas motor engines with a counter shaft for
driving or actuating the valves, the said shaft having a motion always in the same
direction whatever be the direction of the engine's inotion, substantially as herein-
before described.
Fifth. Effecting the ignition of the gas in gas motor engines by means of a valve
shearing off the upper part of an otherwise perinanent igniting jet of flame, the
bottom part of such flame providing for continuity of combustion, substantially as
hereinbefore described.
Sixth. Constructing or arranging gas motor engines so that the piston rod is
supplied with water by an annular space around it, such water being enclosed
between two stuffing boxes and glands, and the water entering the rod at right
angles, or nearly so, to its axis. substantially as hereinbefore described.
Seventh. In gas motor engines in which combustion takes place within the
cylinders in a manner such as that herein before described, I claim the employment
of a speed governor controlling the admission of the combustible gas to the motor
cylinder combined with a pressure governor controlling the work done by the
compressing pump or pumps, substantially as hereinbefore described.
In witness whereof, I, the said Joseph John Butcher, have hereunto set my
hand and seal, this Twenty sixth day of April, One thousand eight hundred
and eighty
JOSEPH JOHN BUTCHER. (L.S.)