Improvements in Gas-motor Engines.
Year: 1889

page_text: Date of Application, 10th Dec., 1889
Complete Specification Left, 10th Sept., 1890-Accepted, 11th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements in Gas-motor Engines.
I FREDERICK WILLIAM LANCHESTER, of 13 Bedford Row London W.C. Engineer
do hereby declare the nature of this invention to be as follows :-
My invention has for its object to construct a gas engine in such manner that
the valves governor and other supplementary parts usually actuated from the engine
crank shaft are automatically actuated without the intervention of any mechanical
gear and consists in admitting air and gas to the cylinder through suction valves
which are closed during the compression of the charges and during the working and
exhaust strokes of the engine; of an exhaust valve which is only opened at the end of
the working stroke after an explosion and is closed by a spring or weight at the end
of the return or exhaust stroke; in a governor actuated by gaseous pressure and
exercising control over the ignition gear so that when the speed of the engine exceeds
a predetermined amount no ignition takes place, the charge being expanded during
the next stroke to be again compressed, and so on it being finally exploded on the
first out stroke in which the speed of the engine has again fallen to or below its
normal amount; and in lubricating the piston connecting rod and crank shaft by
running them in an oil bath.
The exhaust value'is of the mushroom type with a lìft equal to about half its'
diameter and opens from a space hereinafter called the exhaust chamber into the
compression chamber at the end of the working cylinder. The exhaust chamber also
communicates with the cylinder by a port which is overrun by the working piston
towards the end of its stroke. The exhaust pipe terminates in a box projecting into
the exhaust chamber. The valve spindle passes through a guide formed in one of the
walls of this box and is rigidly attached to a small piston working in a short
cylindrical aperture in the opposite wall. The pressure admitted to the exhaust
chamber on the piston overrunning its port after an explosion opens fully the exhaust
valve by acting on the underside of the exhaust valve and on the small piston which
overrunning the end of its cylinder opens communication between the compression
chamber and the exhaust pipe. The exhaust valve is kept open during the return
stroke by the pressure exerted by the escaping gases on the small piston the escaping
gases being throttled at this point and is closed by its own weight or by a spring.
In a modification the exhaust valve may be opened by means of the pressure of
the products of combustion a portion of which at the end of the working stroke are
admitted to a chamber and act on a piston connected to the exhaust valve & are
exhausted therefrom by a port and passage in the working piston at the end of the
exhaust stroke.
The feed valve is a simple lift valve admitting air direct and raising with it the gas
mixing valve.
The form of ignition apparatus is preferably a simple tube igniter opening into a
passage leading from the compression chamber to a cavity of suitable capacity. The
ignition is controlled by a valve which shuts off this cavity and also the ignition tube
when the speed of the engine and consequently that of the entering gases exceeds a
certain amount which may be regulated by the extent of play permitted to the
valve.
In order to lubricate the piston and connecting rod both connecting rod and crank
are completely boxed in by a casing and made to run in a bath of oil.
The oil running down the roof of this casing passes through a tube on to the piston.
This casing may be made air tight with an outlet valve and be kept by the motion
of the piston in a state of partial vacuum maintaining the connecting rod constantly
in a state of compression and thus preventing the knock due to backlash.

page_text: It will be readily seen that an engine constructed according to my invention will
run continuously in the direction in which it is started and can be worked as a com-
pression engine receiving an impulse once in every two revolutions when working
at its full power or may be worked without compression with an impulse every
revolution by means of a short pipe communicating with the cylinder at a point over-
run by the piston at about mid-stroke and opening near the top of a Bunsen burner
the said tube containing a valve which is automatically closed by the explosion.
This low pressure ignition is specially useful in starting the engine and the valve
may be permanently closed when the engine is running.
Dated this 10th day of December 1889.
WHEATLEY & MACKENZIE
40, Chancery Lane, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Gas-motor Engines.
I, FREDERICK WILLIAM LANCHESTER of 13 Bedford Row, London, W.C. Engineer,
do hereby declare the nature of this invention and in what manner the same]
is to be performed, to be particularly described and ascertained in and by the
following statement:-
•
My invention has for its object to construct a gas engine in such manner that the
valves governor and other supplementary parts usually actuated from the engine
crank shaft are automatically actuated without the intervention of any mechanical
gear and consists in admitting air and gas to the cylinder through suction valves
which are closed during the compression of the charges and during the working and
exhaust strokes of the engine; of an exhaust valve which is only opened at the end of
the working stroke after an explosion and is closed by a spring or weight at the end
of the return or exhaust stroke; in a governor actuated by gaseous pressure and
exercising control over the ignition gear, so that when the speed of the engine
exceeds a predetermined amount no ignition takes place, the charge being expanded
during the next stroke to be again compressed, and so on, it being finally exploded on
the first out stroke in which the speed of the engine has again fallen to, or below its
normal amount; and in lubricating the piston connecting rod and crank shaft by
running them in an oil bath.
The exhaust valve is of the mushroom type with a lift equal to about half its
diameter and opens from a space-(hereinafter called the exhaust chamber)-into
the compression chamber at the end of the working cylinder. The exhaust chamber
also communicates with the cylinder by a port which is overrun by the working piston
towards the end of its stroke. The exhaust pipe terminates in a box projecting into
the exhaust chamber. The valve spindle passes through a guide formed in one of the
walls of this box and is rigidly attached to a small piston working in a short
cylindrical aperture in the opposite wall. The pressure admitted to the exhaust
chamber on the piston overrunning its port after an explosion opens fully the exhaust
valve by acting on the underside of the exhaust valve and on the small piston,
which overrunning the end of its cylinder, opens communication between the com-
pression chamber and the exhaust pipe. The exhaust valve is kept open during the
return stroke by the pressure exerted by the escaping gases on the small piston, the
escaping gases being throttled at this point, and is closed by its own weight or by a
spring.
1
In a modification ‘the exhaust valve may be opened by means of the pressure of
the products of combustion, a portion of which at the end of the working stroke are
admitted to a chamber and act on a piston connected to the exhaust valve and are
exhausted therefrom by a port and passage in the working piston at the end of the
exhaust stroke.
The feed valve is a simple lift valve admitting air direct and raising with it the gas
mixing valve.

page_text: The form of ignition apparatus is preferably a 'simple tube igniter opening into a
passage leading from the compression chamber to a cavity of suitable capacity. The
ignition is controlled by a valve which shuts off this cavity and also the ignition tube
when the speed of the engine and consequently that of the entering gases exceeds a
certain amount which may be regulated by the extent of play permitted to the
valve.
In order to lubricate the piston and connecting rod both connecting rod and crank
are completely boxed in by a casing and made to run in a bath of oil.
The oil running down the roof of this casing passes through a tube on to the piston.
This casing may be made air tight with an outlet valve and be kept by the motion of
the piston in a state of partial vacuum maintaining the connecting rod constantly in a
state of compression and thus preventing the knock due to back lash.
It will readily be seen that an engine constructed according to my invention will
run continuously in the direction in which it is started and can be worked as a com-
pression engine receiving an impulse once in every two revolutions when working at
its full power or may be worked without compression with an impulse every revolution
by means of a short pipe communicating with the cylinder at a point overrun by the
piston at about mid stroke, and opening near the top of a Bunsen burner, the said tube
containing a valve which is automatically closed by the explosion. This low pressure
ignition is specially useful in starting the engine and the valve may be permanently
closed when the engine is running.
The accompanying drawings illustrate arrangements of parts used by me in
carrying my invention into effect.
"
Figs. 1, 2, 3, section, elevation and plan respectively-show the construction and
mode of operation of my exhaust valve.
Figs. 4, 5, 6, similarly illustrate the inlet gas and air valves while
Figs. 7, 8, 9 and 10, refer to the combined igniting and governing apparatus and
Fig. 11 is a diagramatic section of an engine constructed in accordance with my
invention arranged to show the lubricating devices and the interdependence of the
various parts.
r
Referring to Figs. 1, 2 and 3; when an explosion occurs in the cylinder and the
piston is thrust forward, it overruns when nearing the end of its stroke a port in
communication with the port A opening into the exhaust chamber B. The terminal
pressure in the cylinder thus acts to increase the pressure in B and equilibrates the
pressure on both sides of the exhaust valve C, which as I have herein before stated, is
of the mushroom type. The valve C, by its spindle D, is rigidly connected to the
piston E working in the cylindrical aperture G. The cylindrical aperture G makes
communication between the exhaust chamber B and the exhaust discharge pipe H,
which communication is closed however by the piston E. When the pressure in the
exhaust chamber B rises sufficiently, the piston E is thrust upwards, as the exhaust
pipe H is open to the atmosphere and is therefore at atmospheric pressure. The
movement of the piston E opens the valve C which valve remains open so long as the
pressure in the cylinder exceeds external atmospheric pressure sufficiently to hold
open the piston E against the pull of the spring F which tends to close the valve.
The engine piston therefore returns discharging the exhaust gases with just enough
back pressure against it to keep the piston E out of the cylindrical aperture G against
the spring F. The lift of the valve C is sufficiently great to avoid any closing action
by the rush of the exhaust gases from the cylinder, and this lift is determined by the
distance between the lower edge E¹ of the piston E and the upper edge G¹ of the
cylindrical aperture G. As no exhaust gases can escape from the exhaust chamber B
until the piston E has lifted out of G, the lift of the valve C is necessarily governed.
by the distance E¹ G₁. When the piston has completed the exhausting stroke, the
spring F closes the exhaust valve C. In order to avoid shock upon the rapid opening
of the valve C by the piston striking against the end of the bored spindle guide I, a
dash pot on cylinder K is provided as part of the piston E but such dash pot may be
placed in any other convenient position. The case or cover L may be conveniently

page_text: arranged as shown with a valve seat ground on, to permit of ready inspection, or any
other suitable method of construction may be adopted.
Referring to Figs. 4, 5 and 6 illustrating the inlet gas and air valve, M is the
inlet valve having the gas valve N on the end of its spindle O. When the piston
inoves forward on its suction stroke the valve M lifts automatically moving with it
the gas valve N; air enters by the passage P and in passing over the holes QQ,
Q, Q, Q &c. on its way to the cylinder it becomes impregnated with gas. When
the valve N is opened, gas from the supply pipe R flows into the space a and thence
it supplies the annular channel b which feeds the distributing holes QQ, Q¹ Q¹ &c.
The valve N moves slightly on the spindle O, gas pressure tight, in order to allow it
to seat itself independently. of M. The spiral spring C brings the gas valve N to
its seat and brings the gas and air valve M very nearly down.
Referring to Figs. 7, 8, 9 10 and 11 illustrating the combined igniting and
governing apparatus, the tube igniter connects to the arrangement shown in Figs. 7
and 8 by the passage S through the valve T which acts in the cylindrical chamber T¹.
So long as the valve T is in the position shown in Fig. 7 free communication is
maintained, between the igniter tube and the explosion space of the engine cylinder
by way of the groove d the holes e, f, and the larger hole g. As the area of those
holes is amply sufficient to carry flame without extinction the mixture in the cylinder
is ignited regularly on the completion of each compressing stroke at the point deter-
mined by the proportions of the igniter tube. If however the speed of the engine
I should exceed the predetermined rate then the rapidity of compression becomes so
great that the holes f, h, connecting the chamber U with the larger hole g and the
cylinder, become insufficient to supply the chamber U rapidly enough, the pressure
in g and therefore under the valve T rises above that in the chamber U and so the
valve T is forced up and seats against the lower part of the chamber as shown at
Fig. 10. This closes the chamber U and the pressure below T keeps it against the
seat until the charge has expanded again and the pressure in U becomes sufficient
to force it down. In the position shown in Fig. 10 the groove d is carried above the
passages S and e and the band is brought opposite them. The diameter of the
body of the valve at this position is slightly reduced so as to leave sufficient area
for the inflammable compressed gases in the cylinder to pass to the igniter tube and
there become ignited but the surface and area is so proportioned that although flame
is produced in the igniter tube yet the flame cannot pass through the narrow space
existing between the band i of the valve and the cylinder in which it works. The
ignition therefore does not reach the gases in the engine cylinder and so long as the
valve T occupies its upper position at the moment of ignition, the mixture in
the cylinder is compressed at every revolution but does not ignite except in the
igniter tube. The cylinder although in free pressure communication with the tube is
not in thermal communication. When the speed falls enough to prevent the valve T
from being thrust against its upper seat the ignition recommences, the exhaust valve
is operated on by the terminal pressure in the cylinder when the piston completes its
working stroke and the whole cycle of operations is performed causing an impulse
every two revolutions till the speed again exceeds the limit and the valve T acts to
prevent the ignition reaching the cylinder. The screw shown on Figure 7
through the stuffing gland and is used to adjust the position of the piston valve T
with regard to the hole h and the upper seat. If the valve is raised sufficiently to
almost cover the hole then very little compressed mixture can find its way by h
to the chamber U so a low speed of compression causes the pressure to increase
rapidly below the valve T and so force it up against the upper seat. In this manner
it will be readily understood that the working speed of the engine may be adjusted
by means of the screw k within certain limits. The adjustment may be effected in
another way by a screw or valve controlling the hole so as to close it up to a
greater or less extent and thereby decrease the rate at which gases can flow into the
chamber U from the compression space of the cylinder. The valve T may also be
controlled by spring instead of in either of the foregoing modes and the spring.
passes

page_text: arranged to resist it rising to its seat and by increasing the compression of the spring
the speed of the engine may be varied.
Figure 11 illustrates diagrammatically the general arrangement of an engine con
structed in accordance with my invention in such a manner as to make clear. the,,
relationship of the various parts. The same lettering is adopted for similar parts..
as in the figures herein before referred to. The automatic oiling arrangement is also
indicated. The piston V is shown at its extreme out position where. it has...
uncovered the port W (Fig. 11) which communicates with the port. A in the
exhaust valve casing A¹. After the working stroke, the terminal pressure in the
cylinder is about 30 lbs. per square inch and this pressure by the ports W and A-
acts on the piston E (Fig. 1.) and opens the exhaust valve C to a sufficient extent...
to allow the burned gases to discharge by way of the piston E in Figure 1. So
long as the piston V continues its exhausting stroke the piston E is held up and,
with it the valve C the exhaust gases creating just enough back pressure to accom-:;
plish this. When the piston V terminates its inward exhausting stroke the exhaust.
valve C is closed by the spring shown in Fig. I and on the charging stroke being
commenced the inlet gas and air valve M opens and with it the gas valve N, the
passages band a in the casing M admit gas and air to the cylinder X as herein-
before explained and the cylinder becomes charged with an explosive mixture of gas
and air. When the piston V makes its inward compressing stroke the exhaust..
valve-C remains closed as no pressure can be applied to open it unless the gases in
the cylinder have a pressure superior to the atmosphere when the piston is full out...
When the compressing stroke is completed or approaches completion the igniter.
tube Z (Fig. 11) fires the charge through the passages and groove in the valve, of:
the governing devices Y and this action gives an impulse every second stroke and is
continued until the engine exceeds the predetermined speed. The piston valve T
(Fig. 7) then acts within the apparatus Y and prevents the flame generated in the
igniter tube, Z. from reaching the combustion space. The mixture then simply
expands on the outstroke and is compressed on the instroke until the speed. falls
sufficiently to allow the ignition to occur again. The usual water jacket is indicated
in Fig. 11 and the crank and connecting rod are enclosed in the casing m.
bottom of the casing is formed to receive oil as at n into which the crank and
connecting rod end dash at every revolution and are thereby lubricated; a quantity
of oil is also thrown against the casing and that portion which strikes the upper part
is allowed to drain to the projection O, whence it passes by the pipe passage or
gutter p to the oil cup 9 which it keeps filled and the excess flows back over the
ledge Ô. The level of this ledge is arranged to keep the oil cup filled to a proper
depth. The screw is used to adjust the quantity of oil fed to the cylinder and the.
drops may be allowed to fall through the space in such manner as to be visible. The
cylinder X is covered by a cover S in order to prevent oil from being splashed in at
the front. The connecting rod works through a slot in the cover.
The
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner it is to be performed I declare that what I claim is :-
1. In gas or inflammable vapour engines; the use of a combination consisting of
an exhaust valve opened by the pressure of the burned gases acting on a piston; the
said gases operating through a port in the engine cylinder, which port is overrun by
the power piston towards the termination of its working stroke, so that the exhaust
valve is opened only after a working stroke has been completed substantially as
hereinbefore described and illustrated.
2. In gas or inflammable vapour engines the use of a combination consisting of an
exhaust valve opened by the pressure of the burned gases acting on a piston; the
said gases operating through a port in the engine cylinder, which port is overrun by
the power piston towards the termination of its stroke, so that the exhaust valve is
opened only after a working stroke has been completed and is held open by the back
pressure of the escaping gases under the action of the engine piston substantially as
herein before described and illustrated in the accompanying drawings.

page_text: 3. In gas or inflammable vapour engines the arrangement of automatic engine
comprising an exhaust valve operated by pressure applied by means of a port overrun
by the piston, an automatic inlet gas and air valve and an igniter tube freely open to
the cylinder which ignites upon compression substantially as herein before described
and illustrated having special reference to Fig. 11 of the accompanying drawings.
4. In gas or inflaminable vapour engines the use of a governing device consisting
of a loose piston valve and regulating chamber into which compressed gases flow,
the passages being so arranged that when the predetermined speed is exceeded the
pressure rises more rapidly under the piston valve than above it and so the valve is
forced towards the regulating chamber and cuts off communication between the
cylinder and the igniter tube.
...
5. In gas or inflammable vapour engines the use of a governing device consisting
of a loose piston valve and a regulating chamber into which compressed gases flow,
the passages being so arranged that when the determined speed is exceeded the
pressure rises more rapidly under the piston valve than above it and so the valve is
forced towards the regulating chamber and cuts off flame communication between the
igniter tube and the cylinder and prevents the ignition which takes place in the tube
from being communicated to the contents of the compression space substantially
✓as hereinbefore described and illustrated with reference to Figures 7, 8, 9 and 10 of
the accompanying drawings.
6. In gas or inflammable vapour engines; maintaining a constant level in an oil
cup or cups lubricating the engine by allowing the oil dashed on a retaining case by
the connecting rod to fill a pocket such as 0 substantially as herein described and
illustrated in Figure 11 of the accompanying drawings.
Dated this 9th day of September 1890.
MARKS & CLERK,
13, Temple Street, Birmingham, Agents.