IM- PROVEMENTS IN AND RELATING TO GAS MOTOR ENGINES
Year: 1879

page_text: LETTERS PATENT to Frederick William Turner, of St. Alban's Iron Works,
St. Alban's, in the County of Hertford, Engineer, for the Invention of "IM-
PROVEMENTS IN AND RELATING TO GAS MOTOR ENGINES."
PROVISIONAL SPECIFICATION left by the said Frederick William Turner
at the Office of the Commissioners of Patents on the 29th March 1879.
FREDERICK WILLIAM TURNER, of St. Alban's Iron Works, St. Alban's, in the
County of Hertford, Engineer. "IMPROVEMENTS IN AND RELATING TO GAS MOTOR
ENGINES."
This Invention relates, first, to improvements in direct acting rotary engines
worked by the explosive and expansive force of a mixture of combustible gas or
vapor and air in a cylinder.
The chief objects of this Invention are to increase the speed of working the
number of strokes of the piston revolutions of the main shaft and rapidity of
ignition, to ensure while working at this increased speed a more equal distribution
of force upon the shaft; to control or govern such force by regulating more
accurately than heretofore the admission of air and gas to the cylinder; to diminish
the friction caused by the angularity of the crank connecting rod upon the piston
or guides of the same, and to simplify the engine by constructing the slide valve to
perform the three separate functions of regulating the admission, the ignition, and
the discharge of the gas.
The said Invention is carried into practice as follows, that is to say :-
Upon one end or side of a cylinder I form a port face in which are three ports
one above the other. The upper and middle ports communicate with the interior
of the said cylinder, while the lower port communicates with the exhaust pipe.
The upper port is for the admission of gas and air, and for igniting the charge
within the cylinder. The middle port is for the admission of gas and air before the
upper port is uncovered by the slide valve in the first part of the piston's ascent; it
also serves for the discharge of the gases during the inward or downward stroke of
the piston when put into communication with the lower port by means of the.
slide valve, the lower port being the exhaust port. Between the said port face and.
a fixed back plate I arrange the slide valve which is flat, and has formed in it a

page_text: cavity opening towards the cylinder. This cavity communicates during a portion
of the stroke by means of a passage in the back thereof with a port in the back
plate provided for the admission of air in the back of the valve. Above the afore-
said passage I form a small igniting port for the admission of the igniting flame,
whose burner or source is external to the slide-valve. This port is closed against
internal pressure by a valve preferably made of steel or platinum. During the
upward movement of the slide the igniting port passes above the back plate, and
in this position is opposite the upper port in the cylinder when the pressure of the
atmosphere (acting against the partial vacuum produced in the cylinder by the
movement of the piston), forces open the igniting valve driving the flame through
the port, which flame then ignites the charge in the cylinder. I thus dispense with
the internal lighting flamé hitherto used in the slide-valve of such engines.
To more exactly or accurately regulate the admission of air to the cylinder,
I attach to the back plate a valve-box having at its lower extremity a seat or seats,
and I provide a globular valve or valves of india-rubber, vulcanite, or other suitable
material to work on the said seat or seats. Through the top of the said box and
over each valve I fit a screw having at its lower end a cup, by means of which the
lift of each of the said globular valves is limited and regulated as desired. The
said screw is depressed as the globular valve wears smaller. By means of a similar
valve box, valve, and screw attached to the side of the back plate I regulate the
supply of gas or combustible vapour, which passing through a small port formed in
the back plate and leading to the slide valve is by the movement of the latter
admitted through a corresponding port to the cylinder simultaneously with the
charge of air.
The aforesaid slide valve is worked directly by an eccentric without levers or
intermediate gear from the main shaft, the cylinder being charged with gas and air,
and the same being ignited and discharged at every revolution of the main shaft.
To diminish upon the piston or the guides the friction caused by the angularity
of the connecting rod during the combustion of the gaseous charge, I so arrange the
main shaft that its centre or axis will be about one eighth part of the length of the
stroke, laterally out of line with the axis of the cylinder at the side thereof,
traversed by the crank pin during the inward or downward stroke of the piston.
To diminish the temperature of the aforesaid slide valve and prevent the burning
of the lubricating material applied to the same I make the back plate hollow, and
by means of two pipes cause water to circulate through the said plate. In some
instances I also provide for the circulation of water through the slide valve.
In gas engines of this class as heretofore constructed the fly wheel has been fixed
upon the main shaft at a part not adjacent to the crank or disc to which the force
is applied; this arrangement is disadvantageous as the torsion upon the shaft at the
moment of explosion is very great, and by the sudden impulse the fly wheel is
liable to become loose. To prevent this difficulty I hang the fly wheel upon the
end of the said shaft, and utilize one of the arms of the said wheel for the reception
of the crank pin which is firmly fixed therein..
In engines of considerable power I employ an air pump placed at an angle and
connected by a port or passage to the cylinder; the plunger of the said air-pump is
connected to the same crank-pin as the piston of the cylinder; or if the pump is
fixed in the same line with the cylinder the air plunger is connected to a separate
crank placed at an angle to the crank of the cylinder piston, in such manner
that while the said piston is rising at the commencement of its stroke, the
pump plunger travels about a corresponding distance downward, forcing the gas
and air which it has previously drawn in beneath it into the cylinder. Imme-
diately after the said pump plunger reaches the end of its stroke the charge in the
cylinder is ignited, the piston finishing its course by the explosive and expansive
force of the gases, during which time the pump plunger draws in a fresh charge.
In this case I employ a slide valve differing from that herein before described, as in
addition to the port for the admission of the gases and exhaust cavity, it is
provided with an igniting chamber containing an internal jet. By this arrange-

page_text: ment I expel the whole of the foul gases from the cylinder at each stroke of the
piston, and dispense with the necessity of providing a large space in the cylinder at
the end of the piston's course to receive the charge, as in engines of this class
hitherto constructed, to work with compressed charges. The speed of the engines
is regulated by the aforesaid globular gas supply valve assisted by any suitable
governor driven from the main shaft of the engine.
To adapt these engines for locomotive traction or hauling purposes, I propose
to place across a frame mounted on travelling wheels, two, three, or four cylinders
to work cranks placed at such angles upon the main shaft as to ensure con-
tinuous propulsion of the same; upon the end of the main shaft I fit a barrel having
at each end a flange provided with two pins each carrying a spur wheel; these gear
into annular or internally toothed wheels mounted in separate bearings. Around
the outside of the said annular wheels I fit brake bands attached to suitable levers
to be worked by hand, in such manner that when one wheel is clipped and held
fast the other is released and allowed to revolve. In connection with the spur
wheels mounted upon the pins herein before mentioned I fit two spur pinions
upon the engine shaft; these are of different diameters and arranged in such a
manner that when the annular wheel with which the smaller pinion is in con-
nection is held fast a slow speed of the barrel is obtained, and when the annular
wheel with which the large pinion is in connection is held fast a quicker speed of
the barrel is obtained; the said barrel being geared by bevel or other wheels,
or by a chain with the travelling axle of the engine, a slow speed for starting or
for running up inclines, and a quicker speed for running on levels are obtained,
or when the levers herein before mentioned are placed in a middle position; both
the aforesaid annular wheels are released and the driving of the travelling axles
ceases, although the engines may continue to run. By fixing a chain or rope to
the aforesaid barrel it may be used for winding the engine out of difficult places
or for lifting weights.
The gearing may be modified in various ways to obtain the same result.

page_text: valve d in the first part of the piston's ascent; it also serves for the discharge of
the gases during the inward or downward stroke of the piston c when put into
communication with the lower or exhaust port 63 by means of the slide-valve d.
Between the said port-face 6* and the fixed back plate e I arrange the said slide-
valve, which has formed in it a cavity d¹ opening towards the cylinder b. This
cavity communicates by means of the aperture d in the back of the valve with a
port e in the back plate e provided for the admission of air. In the back of the
valve d above the aforesaid aperture d' I form a small igniting port d³ for the
admission of the igniting flame, whose burner e* or source is external to the slide-
valve. This port is closed against internal pressure by a valve k, preferably, made
of steel or platinum, and which I term an igniting valve. During the upward
movement of the slide-valve d the igniting port d³ passes above the back plate e,
and in this position is opposite the upper port 6' in the cylinder port-face, when
the pressure of the atmosphere (acting against the partial vacuum produced in the
cylinder 6 by the movement of the piston c) forces open the igniting valve k, driving
the flame through the port b', which flame then ignites the charge in the cylinder b,
I thus dispense with the internal lighting flame hitherto used in the slide-valve
of such engines, and avoid the inconvenience resulting from the use of the
same.
To provide for more exactly or accurately regulating the admission of air to the
cylinder 6 I connect with the back plate e a valve box l, having at its lower side a
seat or seats 1, on each of which I place a globular valve 13 of india-rubber, vulcanite,
or other suitably light material. I use valves of these light materials for the
reason that metal valves would be too heavy to lift readily by the pressure of the
atmosphere. Through the top of the said box l, and over each valve 1 I fit a
screw having at its lower end a cup; by means of this screw the lift of each of the
said globular valves is limited and regulated as desired. The said screw is screwed
down or inward as the globular valve wears away, and is thereby reduced in size.
By means of a similar valve-box e², valve e³, and screw et, in connection with the
back plate d, as shewn in Figure 5, I regulate the supply of gas or combustible
vapour, which passing through a small port et formed in the back plate, and leading
to the slide-valve d, is by the movement of the latter admitted through a corre-
sponding port to the cylinder simultaneously with the charge of air.
The aforesaid slide-valve is preferably worked directly by an excentric m
without levers or intermediate gear from the main shaft, the cylinder b being
charged with gas and air, and the same being ignited and discharged at every
revolution of the said main shaft.
To diminish upon the piston or the guides the friction caused by the angularity
of the connecting rod during the combustion of the gaseous charge, and in some
cases to enable me to dispense with guides for the piston-rod, I so arrange the
main or crank shaft g that its centre or axis will be about one eighth part of the
length of the stroke laterally out of line with the axis of the cylinder b, and at
the side thereof traversed by the crank pin during the inward or downward stroke
of the piston. This arrangement is clearly illustrated in Figure 2, in which the
line 1, 1, indicates the vertical axis of the cylinder, and the line 2, 2, the vertical
line intersecting the axis of the crank-shaft.
To diminish the temperature of the aforesaid slide-valve and prevent the
burning of. the lubricating material applied to the same, I make the back plate
hollow as shewn, and by means of two pipes e, e7, cause water by its own
expansion under the influence of heat to circulate through the said plate. I am
thus enabled to obtain a circulation of water through the said back plate, without
the use of pumps or other forcing apparatus.
In engines of more than two-horse power, I prefer to adopt the arrangement
illustrated in Figure 6, that is to say, I employ a pump n placed at an angle, and
connected by a port or passage n' to the cylinder b; the plunger n² of the said
pump is connected to the crank pin h', to which the piston of the cylinder b is also
connected. Or if the pump n is placed in line with the cylinder b, as shewn in

page_text: Figures 7 and 8, the plunger n² of the said pump is connected through the medium
of the rock shaft o and its adjuncts, or by other suitable means with a separate
crank or excentric p placed at such an angle to the crank h of the piston c, that
while the piston c is moving at the commencement of its outward or effective
stroke the pump-plunger n² completes its inward stroke, and thereby the gas and
air which have been just previously drawn into the said pump are forced through
the passage n³ into the cylinder b. This result is also accomplished by the arrange-
ment of the piston and plunger both connected with one crank, as shewn in
Figure 6. In either case immediately the said pump-plunger n reaches the end of
its stroke the charge in the cylinder 6 is ignited, the piston c finishing its course by
the explosive and expansive force of the gases during which time the pump-
plunger n draws in a fresh charge. In the engine provided with this pump, I
employ a slide-valve differing from that hereinbefore described, as in addition to
the port for the admission of the gases and exhaust cavity, it is provided with an
igniting chamber containing an internal jet as heretofore used.
By the employment of the pump arranged and operating as above described, I
expel nearly the whole of the foul gases from the cylinder 6 at each stroke of the
. piston thereof; I thereby obtain at each stroke a charge not deteriorated by the
admixture of foul gas, and dispense with the necessity of providing an intermediate
chamber between the pump and cylinder, or a large space in the cylinder at the
end of or beyond the piston's course or stroke to receive the charge, as in engines
of this class hitherto constructed to work with compressed charges.
The speed of my improved engines is regulated by the aforesaid gas-supply
valve, assisted by any suitable governor driven from the main shaft of the engine
or in any suitable manner.
To adapt these engines for locomotive, traction, or hauling purposes, I propose to
place across a frame mounted on travelling wheels two, three, or four cylinders to
work cranks, placed at such angles upon the main shaft as to ensure continuous
rotation of the same. Upon the end of the said main shaft I fit a barrel q having
at each end a disc or flange q¹ provided with two pins q³, each carrying a spur-
wheel r.
These wheels gear into annular or internally toothed wheels 8 mounted
in separate bearings, or arranged in any suitable manner to turn independently of
the shaft g.
Around the outside of the said annular wheels I fit brake-bands 8¹
attached to suitable levers 8 to be worked by hand in such manner that when
either one of the said annular wheels is clipped and held fast the other is released
and allowed to revolve. In connection with the spur wheels r mounted upon the
aforesaid pins I fit two spur pinions u, v, upon the engine shaft g; these pinions
u, v, are of different diameters, and arranged in such manner that when either of
the said annular wheels is held by the brake the pinion on the shaft g acting
through the wheels r will cause the disc and barrel to rotate, but when the said
annular wheel is released from the brake the said pinion will cause the rotation of
the same without moving the disc.
When the annular wheel with which the smaller pinion u is geared is held fast
a slow speed of the barrel is obtained, and when the annular wheel with which
the large pinion is in connection is held fast, a quicker speed of the barrel is
obtained. The said barrel being geared by bevel wheels, a chain and chain-wheels,
or connecting rods or other suitable means with the travelling axle of the engine,
a slow speed for starting or for running up inclines, and a quicker speed for
running on levels may be obtained as desired; or when the levers hereinbefore
mentioned are placed in a middle position both the aforesaid annular wheels are
released, and the driving of the travelling axles ceases although the engines may
continue to work. By fixing a chain or rope to the aforesaid barrel it may be
used for winding the engine out of difficult places, or for lifting weights, or for
similar purposes.
Having thus fully described my said Invention and the manner of performing t
the same, I wish it understood that I claim,―
First. The employment in a rotating crank engine driven by the explosive

page_text: and expansive force of gas and air, of a slide valve constructed to perform the
three separate operations or functions of regulating the admission of the gaseous
charge into the cylinder, the ignition of the charge, and the discharge or exhaust of
the foul gases.
Second. Providing the slide-valve of such an engine with an igniting valve, for
the purpose specified.
Third. In combination with the slide-valve of such an engine the globular valve
or valves formed of india rubber, vulcanite, or other similarly light material, and
provided with the screws or other adjusting devices for regulating the admission of
the air or gas, or both, as above specified.
Fourth. In a rotating crank engine operated by the explosive and expansive
force of gas and air, providing in combination with the slide-valve the port face
constructed with three ports, substantially as and for the purpose specified.
Fifth. In such an engine the arrangement, whereby the axis or centre of the
crank shaft is out of line or coincidence with the axis of the cylinder, as above
described and for the purpose specified.
Sixth. In combination with the slide-valve the hollow back plate provided with
the means above described for maintaining the circulation of water therein with-
out the aid of a pump or other forcing apparatus, for the purpose specified.
Seventh. A rotating crank engine driven by the explosive and expansive force of
gas and air, and consisting of the parts constructed and combined, as shewn in
Figures 1 to 5 of the Drawings, and operating as set forth.
Eighth. The engine wherein the charging pump is arranged at an angle to the
cylinder and connected therewith, and to the crank shaft as shewn in Figure 6 of
the Drawings, for the purpose specified.
Ninth. The modification of the said engine wherein the pump is placed with its
axis in line or coincidence with the axis of the cylinder, as shewn in Figures 7 and
8 of the Drawings, for the purposes specified.
Tenth. The apparatus comprising the wheel gearing and brakes arranged in
combination with the crank-shaft of the engine, in such a manner that while the
engine continues working at a uniform speed the speed of the vehicle may be
diminished or increased, or stopped, as above set forth.
In witness whereof, I, the said Frederick William Turner, have hereunto set
my hand and seal, this Twenty ninth day of September, in the year of
our Lord One thousand eight hundred and seventy nine.
F. W. TURNER. (L.S.)