Year: 1887

page_text: Date of Application, 19th Aug., 1887
Complete Left, 18th June, 1888
Complete Accepted, 20th July, 1888
We, HERBERT LINDLEY and THOMAS BROWETT, of Sandon Works, St. Simon Street,
Salford, in the County of Lancaster, Engineers, do hereby declare the nature of this
invention to be as follows:
After the
This invention relates to gas motor engines of the kind wherein a charge of
inflammable or explosive gas or vapour or spray mixed with air is drawn into a
cylinder, then compressed, then ignited and afterwards expelled during four successive
strokes of a piston corresponding to two revolutions of the engine, and the object of
this invention is to simplify the construction of such engines and to enable the power
produced to be governed in proportion to the load. To this end the waste products
resulting from an explosion are got rid of or expelled from the cylinder as we will
now explain. At or near the end of the cylinder lying towards the crank-shaft of
the engine are provided holes or ports in such a position that they are uncovered by
the piston on the completion of its out-stroke, that is, its stroke towards the crank-
shaft of the engine. These holes or ports which may be narrow or of small diameter
so as not to open too early, serve to get rid of any excess of pressure over atmospheric
pressure that may remain in the cylinder at the end of a working stroke.
crank has passed the dead centre, the piston begins to return and expels a small
portion of the contents of the cylinder through the holes afore-mentioned, continuing
to expel until it has again covered such holes, unless it be deemed advisable to prevent
such displacement by a loaded check valve or other means, the piston during the
remainder of its in-stroke then deals with the bulk of the products in the cylinder in
one of two ways as we will presently explain, premising that in addition to the holes
or ports above mentioned the engine is fitted with a separate exhaust valve at the
other end of the cylinder, namely, the end further from the crank-shaft: this valve is
capable of being mechanically moved by a lever cam or other well known means and
worked from the engine itself, the actuating mechanism being so arranged as to
operate or not under the control of the governor. A valve is also provided whereby
the charge of air and inflammable vapour or spray can be admitted into the cylinder.
This may be called the charge valve; it may advantageously be of the lift type and

page_text: :
self-acting, that is, adapted to lift when there is a partial vacuum or reduction of
pressure in the cylinder; or means may be provided to operate it mechanically, or a
slide such as is frequently used in gas engines for this purpose may be employed.
But for the purpose of describing the nature of the invention, we will assume the
valve to be a simple mixing valve containing air and gas passages and acting in an
automatic manner, when there occurs a reduction of pressure in the cylinder.
Means must also he provided for firing the charge; these may be of any known
or suitable kind; an electric spark may be caused to pass at the right time into the
cylinder by any convenient means, or a heated tube open to the cylinder or caused
to open thereto by a small slide may be employed, in which case it will usually be
advantageous to introduce a small quantity of pure gas to the tube before the charge
enters, and this can be conveniently done in the slide. In cases where a slide is used
the arrangement can be such that the same mechanical motion that works the exhaust
valve shall also work the firing slide.
The operation of an engine according to this invention may be described as
follows Starting with the piston of the engine at the dead centre in, that is, at its
nearest position to that end of the cylinder that is the further from the crank-shaft,
and at which end there is a clearance space, and assuming this space to be filled with
waste products from a previous explosion, such products being at atmospheric pressure,
the piston then moves, outward, and as the exhaust valve is now closed, produces a
partial vacuum or rarefaction of the contents of the cylinder, consequently the self
acting charge valve lifts and admits a charge of inflammable mixture to the cylinder,
thereby destroying the vacuum therein. When the piston has completed its out-stroke
or has opened communication to the aforesaid holes or pots at or near the outer end
of the cylinder, no more rarefaction can be produced in the cylinder and the charge
valve automatically closes, the piston then begins to return, and after passing the
aforesaid holes or ports compresses the explosive charge into the above mentioned
clearance space at the end of the cylinder. The compressed mixture is then fired by
any suitable means as aforesaid, then the piston is caused to make another out-stroke
by reason of the rise in pressure due to the explosion as is now well understood. On
approaching the end of its out-stroke, the piston uncovers the before mentioned holes
or ports and any excess of pressure remaining in the cylinder above that of the
atmosphere is neutralized by the natural escape of the gases, and thus at the end of
the out-stroke of the piston or thereabouts the cylinder will be full of waste products
at atmospheric pressure. The next instroke of the piston deals with the remainder
of the products in one of two ways, depending entirely on the action of the
governor. Supposing the engine to be running slightly under its normal speed the
governor will then so dispose the mechanism whereby the exhaust valve is operated
that the valve will he lifted and the remainder of the products be expelled so far as
.possible by the piston. Under these conditions the clearance space at the end of the
cylinder will at the termination of the exhausting stroke of the piston be filled with
waste products at or about atmospheric pressure and the cycle as just described will be
repeated. But should the engine be running at a speed slightly in excess of the
normal at the time of the termination of its second out-stroke and when it is on
the point of returning to expel the waste products, then the action of the governor
will be such as to disconnect the exhaust valve from its operating mechanism and
thus the exhaust valve will not be opened. The effect of this will be that the waste
products remaining in the cylinder at atmospheric pressure will be compressed by
the piston into the clearance space at the end of the cylinder as was the charge in the
previous instroke. The firing slide, if there be one, will be operated as before, but
will have no effect as the contents of the cylinder will now be incombustible, the
charge valve will not operate as there will be no vacuum formed in the cylinder; and
the next out-stroke of the piston instead of drawing in a fresh explosive charge will
be performed and aided by the expansion of the compressed waste products. This
alternate compression and expansion of the waste products will go on until the speed
of engine shall have fallen and the exhaust valve shall have been allowed to open by
the governor, whereupon the cycle as first described will be repeated. This method

page_text: equisite for
of dealing with the waste products besides simplifying the mechanism
an engine of this class has the great additional advantage, that during the period
that the engine, by reason of being lightly loaded, does not require to draw in fresh
explosive charges, the contents of the cylinder are not flushed out with air, and the
next entering explosive charge finds the cylinder in the same state as when, in an
engine of the type referred to as usually constructed, an explosion occurs each time
that it is possible, that is to say, at every alternate out-stroke, and thus all explosions
in the cylinder take place under like conditions.
To move the mechanical exhaust valve under control of the governor, any usual
device may be used, the power required being obtained from a rotating shaft driven
by the engine and carrying an eccentric, cam, or other suitable device which may be
made to move or leave at rest on its seat the exhaust valve either by causing to be
moved into or out of gear by the governor a contact or filling piece, or by causing
the governor to alter the position of such cam or eccentric on the shaft which
rotates it. By varying the configuration of the cam it may be made such that
while it opens the exhaust valve always at the same point (when in gear so to do) it
may close the same carlier or later, and so release more or less of the burnt gases in
the cylinder and accordingly cause to be admitted through the gas mixing valve
a corresponding greater or less charge of combustible mixture on the next out-stroke
of the piston.
:-
⠀
An arrangement of tube igniter that inay be used according to this invention is as
follows Between a highly heated tube and the cylinder is interposed a small slide
actuated from the engine in a manner well understood, but the said slide is made
thicker than would be necessary merely to serve as a slide to open or close
communication between the inside of such tube and the port or passage leading to the
cylinder and the transverse hole or port drilled through this slide as is usual in this
form of igniter thus has a greater cubic contact. This slide has two positions given
to it by a suitable cam that is to say, to ignite a charge it is moved rapidly into that
position in which the hole through it makes communication between the inside of the
heated tube and the inside of the cylinder; it is allowed to rest during the working
out-stroke of the piston and, after the contents of the cylinder have been released by
the exhaust port or ports it is moved so that its solid faces cut off communication
between the heated tube and the cylinder. According to this invention the arrange-
ment is such that, while in the second position, the said hole or port in the slide shall
be put into communication with two ports or passages one at each end of itself and one
of which ports is supplied with pure gas or a mixture of gas and air (such as the
engine is supplied with) the other port serving to establish a free way for such pure
gas, or gas and air, to pass through the port or cavity in the slide flushing it of its
contents and filling it with pure gas, or gas and air, so that when next moved into the
position for causing the ignition of the charge in the cylinder, this small volume of
pure gas, or gas and air, will be compressed and mixed with that part of the
combustible charge rushing from the cylinder into the heated tube and will enrich the
same so as to make it produce a more inflaumable gaseous mixture and cause a better
ignition of the main charge in the cylinder.
A modified form of an engine constructed to operate according to this invention
might be arranged as follows:-Instead of having two exhaust ports as above
described, the one exhaust port located at the inner end of the cylinder might be
alone used and the valve controlling the same be lifted momentarily to release the
gases while the piston was at its outward position the cam for actuating such valve
being constructed with a suitable surface in that part which would come in contact
with and actuate the said valve when the governor was in the position due to increase
of speed above the normal, a second or a series of graduated cams being caused to
hold the exhaust valve open during a greater or less time as before described in direct
ratio to any intermediate or other extreme position of the governor-but inasmuch as
most engines in ordinary work do not need to take in and ignite a charge at every
revolution this plan will usually be less advantageous since the exhaust valve would be
always moved once (in some degree) in every two revolutions.

page_text: By another modification it would be possible in an engine having an exhaust valve
as described under the control of the governor and with or without the second
exhaust port to open it every time in any required degree after an ignition of a charge
had taken place to permit the escape of the whole or any portion of the waste
products so that on the next outstroke a combustible charge, varying in volume in
accordance with the amount of waste products allowed to escape would be drawn into
the cylinder and compressed on the next instroke but by using such an igniting slide
as has been above described, or some other mechanically operated igniter and causing
it come into operation to light the charge or not by means of the governor, this
charge might be compressed and allowed to re-expand in the cylinder any number of
times until the speed fell to such a point as would cause the governor to move the
lighting slide and fire the charge. In this arrangement the governor should of course
be made to control the exhaust valve, as well as the igniting slide in such manner as
to prevent the expulsion of a combustible charge before it had been ignited. The
previously described forms are however deemed preferable.
Dated this 19th day of August 1887.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicants.

page_text: Improvements in Gas Motor Engines.
We, HERBERT LINDLEY and THOMAS BROWETT of Sandon Works, St. Simou
Street, Salford, in the County of Lancaster, Engineers 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 :-
This invention relates to gas motor engines of the kind wherein a charge of
inflammable or explosive gas or vapour or spray mixed with air is drawn into a
cylinder, then compressed, then ignited and afterwards expelled during four successive
strokes of a piston corresponding to two revolutions of the engine, and the object of
this invention is to simplify the construction of such engines and to enable the power
produced to be governed in proportion to the load. To this end the waste products
resulting from an explosion are got rid of or expelled from the cylinder as we will
now explain. At or near the end of the cylinder lying towards the crank shaft of the
engine are provided holes or ports in such a position that they are uncovered by the
piston on the completion of its outstroke, that is, its stroke towards the crank-shaft of
the engine. These holes or ports which may be narrow or of small diameter so as
not to open too early, serve to get rid of any excess of pressure over atmospheric
After the
pressure that may remain in the cylinder at the end of a working stroke.
crank has passed the dead centre, the piston begins to return and expels a small
portion of the contents of the cylinder through the holes aforementioned, continuing
to expel until it has again covered such holes, unless it be deemed advisable to prevent
such displacement by a loaded check valve or other means, the piston during the
remainder of its instroke then deals with the bulk of the products in the cylinder in
one of two ways as we will presently explain, premising that in addition to the holes
or ports above mentioned the engine is fitted with a separate exhaust valve at the
other end of the cylinder, namely the end further from the crank-shaft; this valve is
capable of being mechanically moved by a lever cam or other well known means and
worked from the engine itself; the actuating mechanism being so arranged as to
operate or uot under the control of the governor. A valve is also provided whereby
the charge of air and inflammable vapour or spray can be admitted into the cylinder.
This may be called the charge valve; it may advantageously be of the lift type and
self acting, that is, adapted to lift when there is a partial vacuum or reduction of
pressure in the cylinder; or means may be provided to operate it mechanically or
a slide such as is frequently used in gas engines for this purpose may be employed.
But for the purpose of describing the nature of the invention, we will assume the
valve to be a simple mixing valve containing air and gas passages and acting in an
automatic manner, when there occurs a reduction of pressure in the cylinder.
Means must also be provided for firing the charge; these may be of any known
or suitable kind; an electric spark may be caused to pass at the right time into the
cylinder by any convenient means; as a heated tube open to the cylinder or caused to
open thereto by a small slide may be employed, in which case it will usually be
advantageous to introduce a small quantity of pure gas to the tube before the charge
enters, and this can be conveniently done in the slide. In cases where a slide is used
the arrangement can be such that the same mechanical motion that works the exhaust
valve shall also work the firing slide.
The operation of an engine according to this invention may be described as
follows: Starting with the piston of the engine at the dead centre in, that is, at its
nearest position to that end of the cylinder that is the further from the crank shaft,

page_text: and at which end there is a clearance space, and assuming this space to be filled with
waste products from a previous explosion, such products being at atmospheric pressure,
the piston then moves outward and as the exhaust valve is now closed, produces a
partial vacuum or rarefaction of the contents of the cylinder consequently the self
acting charge valve lifts and admits a charge of inflammable mixture to the cylinder,
thereby destroying the vacuum therein. When the piston has completed its out-
stroke or has opened communication to the aforesaid holes or ports at or near the
outer end of the cylinder, no more rarefaction can be produced in the cylinder and
the charge valve automatically closes, the piston then begins to return, and after
passing the aforesaid holes or ports compresses the explosive charge into the above
mentioned clearance space at the end of the cylinder. The compressed mixture is
then fired by any suitable means as aforesaid, then the piston is caused to make
another out-stroke by reason of the rise in pressure due to the explosion as is now
well understood.
On approaching the end of its out-stroke, the piston uncovers the before mentioned
holes or ports and any excess of pressure remaining in the cylinder above that of the
atmosphere is neutralized by the natural escape of the gases, and thus at the end of
the out-stroke of the piston or thereabouts the cylinder will be full of waste products
at atmospheric pressure. The next instroke of the piston deals with the remainder of
the products in one of two ways, depending entirely on the action of the governor.
Supposing the engine to he running slightly under its normal speed the
governor will
then so dispose the mechanism whereby the exhaust valve is operated that the valve
will be lifted and the remainder of the products be expelled as far as possible.
by the piston. Under these conditions the clearance space at the end of the cylinder
will at the termination of the exhausting stroke of the piston be filled with waste
products at or about atmospheric pressure and the cycle as just described will be
repeated. But should the engine be running at a speed slightly in excess of the
normal at the time of the termination of its second out-stroke and when it is on the
point of returning to expel the waste products, then the action of the governor will be
such as to disconnect the exhaust valve from its operating mechanism and thus the
exhaust valve will not be opened. The effect of this will be that the waste pro-
ducts remaining in the cylinder at atmospheric pressure will be compressed by the
piston into the clearance space at the end of the cylinder as was the charge in the
previous instroke. The firing slide, if there be one, will be operated as before but
will have no effect as the contents of the cylinder will now be incombustible, the
charge valve will not operate as there will be no vacuum formed in the cylinder; and
the next out-stroke of the piston instead of drawing in a fresh explosive charge will
be performed and aided by the expansion of the compressed waste products. This
alternate compression and expansion of the waste products will go on until the speed
of engine shall have fallen and the exhaust valve shall have been allowed to open by
the governor, whereupon the cycle as first described will be repeated. This method
of dealing with the waste products besides simplifying the mechanism requisite for
an engine of this class has the great additional advantage, that during the period
that the engine by reason of being lightly loaded, does not require to draw in fresh
explosive charges, the contents of the cylinder are not flushed out with air, and the
next entering explosive charge finds the cylinder in the same state as when in an
engine of the type referred to as usually constructed an explosion occurs each time
that it is possible, that is to say, at every alternate out-stroke, and thus all explosions
in the cylinder take place under like conditions.
To move the mechanical exhaust valve under control of the governor any usual
device may be used, the power required being obtained from a rotating shaft driven
by the engine and carrying an eccentric cam or other suitable device which may be
made to move or leave at rest. on its seat the exhaust valve either by causing to be
moved into or out of gear by the governor a contact or filling piece, or by causing
the governor to alter the position of such cam or eccentric on the shaft which
rotates it. By varying the configuration of the cam it may be made such that while
it opens the exhaust valve always at the same point (when in gear so to do) it may

page_text: close the same earlier or later, and so release more or less of the burnt gases in the
cylinder and accordingly cause to be admitted through the gas mixing valve a
corresponding greater or less change of combustible mixture on the next out-stroke
of the piston.
An arrangement of tube igniter that may be used according to this invention is as
follows:-
Between a highly heated tube and the cylinder is interposed a small slide actuated
from the engine in a manner well understood, but the said slide is made thicker than
would be necessary merely to serve as a slide to open or close communication between
the inside of such tube and the port or passage leading to the cylinder and the
transverse hole or port drilled through this slide as is usual in this form of igniter
thus has a greater cubic contact. This slide has two positions given to it by a suitable
cam, that is to say to ignite a charge it is moved rapidly into that position in which
the hole through it makes communication between the inside of the heater tube and
the inside of the cylinder; it is allowed to rest during the working out-stroke of the
piston and after the contents of the cylinder have been released by the exhaust port
or ports it is moved so that its solid faces cut off communication between the heated
tube and the cylinder. According to this invention the arrangement is such that
while in the second position the said hole or port in the slide shall be put into com-
munication with two ports or passages one at each end of itself and one of which
ports is supplied with pure gas or a mixture of gas and air (such as the engine is
supplied with) the other port serving to establish a free way for such pure gas, or
gas and air to pass through the port or cavity in the slide flushing it of its contents
and filling it with pure gas, or gas and air so that when next moved into the position
for causing the ignition of the charge in the cylinder this small volume of pure gas,
or gas and air, will be compressed and mixed with that part of the combustible
charge rushing from the cylinder into the heated tube and will enrich the same so as
to make it produce a more inflammable gaseous mixture and cause a better ignition
of the main charge in the cylinder.
A modified form of an engine constructed to operate according to this invention
might be arranged as follows:-Instead of having two exhaust ports as above
described the one exhaust port located at the inner end of the cylinder might be alone
used and the valve controlling the same be lifted momentarily to release the gases
while the piston was at its outward position the cam for actuating such valve being
constructed with a suitable surface in that part which would come in contact with
and actuate the said valve when the governor was in the position due to increase of
speed above the normal a second or a series of graduated cams being caused to hold
the exhaust valve open during a greater or less time as before described in direct
ratio to any intermediate or other extreme position of the governor but inasmuch as
most engines in ordinary work do not need to take in and ignite a charge at every
revolution this plan will usually be less advantageous since the exhaust valve would
be always moved once in some degree in every two revolutions.
By another modification it would be possible in an engine having an exhaust valve
as described under the control of the governor and with or without the second exhaust
port to open it every time in any required degree after an ignition of a charge had
taken place to permit the escape of the whole or any portion of the waste products
so that on the next out-stroke a combustible charge, varying in volume in accordance
with the amount of waste products allowed to escape would be drawn into the
cylinder and compressed on the next instroke but by using such an igniting slide as
has been above described or some other mechanically operated igniter and causing it
to come into operation to light the charge or not by means of the governor this
charge might be compressed and allowed to re-expand in the cylinder any number
of times until the speed fell to such a point as would cause the governor to move the
lighting slide and fire the charge.
In this arrangement the governor should of course be made to control the exhaust
valve, as well as the igniting slide in such manner as to prevent the expulsion of
a combustible charge before it had been ignited.

page_text: The previously described forms are however deemed preferable.
In order to more fully explain the method of carrying out our invention we have
appended hereto sheets of illustrative drawings.
Figs. 1 and 2 shew plan and end elevation respectively of an engine constructed to
operate according to this invention as first described. In this arrangement the
exhaust valve is under control of the governor and the combustible charge is drawn
in or is not drawn in, through a self acting mixing valve according as the products
resulting from a previous explosion are allowed to escape or not to escape due to the
action of the exhaust valve as aforesaid.
In the figures the same letters refer to the same parts.
A is the cylinder; in it there works a piston B provided with a connecting rod C
connected to the crank D as is well understood. At or near the end of the stroke of
the piston are a number of holes or parts E so situated that the piston will just
uncover them when approaching its extreme travel towards the crankshaft. Near the
other end of the cylinder is the exhaust valve F with its operating mechanisin
consisting of a lever F and a cam G on the lay shaft H, which rotates at half the
speed of the engine shaft and is operated by means of the gearing L.
At the same end of the cylinder also is provided a second valve J, which has been
described for the purpose of this invention as a self acting lift valve, arranged with
gas and air passages so as to mix the charge in correct proportions in a manner well
known. A slide or piston valve may however be used instead of the valve shewn,
provided means are arranged to ensure its operation when necessary, i.e. whenever the
exhaust valve has been opened. This can be conveniently done, if required, by
causing the slide to be actuated by a cam secured to or operated with the exhaust
cam, so that when the Governor throws the exhaust cam out of action the cam for
moving the slide is also thrown out of action. In the same way by using double
cams, both under the control of the governor the charge valve, if of the lift type can
'be mechanically lifted whenever the exhaust valve has been opened, and in large
engines it may be considered advisable to have the charge valve so lifted.
Figs. 3 and 4 shew an engine constructed according to this modification or a mixing
slide i.e. a slide provided with passages for air and gas and arranged so as to mix them
in correct proportions may be used and operated constantly, but having a self acting
valve or check valve interposed between it and the cylinder so that although the
slide may open the passages for the charge to the underside of the lift valve, the said
charge will not be drawn into the cylinder by reason of the pressure of the compressed
waste products therein supposing the exhaust valve not to have been opened. In this
case it is advisable to have a second check valve of simple construction either on the
gas supply or on the air suction pipe, to prevent gas being wasted by flowing through
the air passages by reason of its own pressure.
It will however. usually be found sufficient to provide the valves as shewn on the
drawings.
We will now again consider the operation of the engine with reference to the
drawing.
After the expansion of any fired charge of combustible mixture, the piston finds
itself near the end of its outstroke i.e. towards the crank shaft. When near to the
end of the stroke the face of the piston uncovers the holes E, E, and any excess of
pressure in the cylinder is allowed to escape into the atmosphere, being first led into
the exhaust pipe; the contents of the cylinder are thus reduced to atmospheric
pressure.
The piston B now begins to return under the influence of the momentum of the fly
wheel and the contents of the cylinder are, after the holes E have been again covered,
dealt with in either of two ways;
Supposing the engine to he running slightly under its normal speed, then the cam G
will be so disposed by the governor that the exhaust valve F is lifted and the contents
of the cylinder are expelled by the instroke of the piston through the valve F and
away through the exhaust pipe into the atmosphere.
On the completion of the instroke of the piston the exhaust valve F closes and then

page_text: the next outstroke is commenced producing a partial rarefaction or vacuum in the
cylinder this causes the charge valve J (which is an ordinary lift valve having a
wide seat in which are perforations for the entrance of gas) to lift and admit a mixture
of gas and air (or of combustible vapour or spray) to the cylinder. This valve J
remains open until the piston reaches the end of its ontstroke or until the holes E are
uncovered and the pressure in the cylinder is brought to that of the atmosphere. The
valve J then closes and the next instroke of the piston compresses the combustible
contents of the cylinder into the clearance space allowed for them and marked K.
This compression forces a portion of the charge into the heated tube L in a manner
now well understood, and the charge is fired. The result is a sudden elevation of
temperature and pressure which causes the piston to make its next outstroke and
complete the cycle.
Supposing on the other hand the engine to be running above its normal speed and
the cam G to be moved by the governor so that it does not operate the exhaust valve F,
then the contents of the cylinder consisting of waste products will be compressed on
the next instroke and there will not be a rarefaction or partial vacuum on the next
outstroke and therefore the charge valve J will not be opened and the next outstroke
of the piston instead of drawing in a fresh charge will be made under the action of
the reexpansion of the compressed waste products and so on.
As has been mentioned before the holes E E can be dispensed with and instead
thereof the exhaust valve F can be caused to lift at the end of each working outstroke
of the piston by means of the cam G provided for working such valve F. The configura-
tion of such a cam is shewn in Figure 5. In a further modification of this invention
the exhaust valve is operated after each working stroke (that is after a charge has
been fired in the cylinder) and a combustible charge is consequently drawn in imme-
diately after, but in order to effect the governing of the engine such charge is ignited
or not ignited according as the speed is below or above the normal.
In an engine constructed according to this modification, a small slide is interposed
between the heated tube L and the cylinder and this slide is actuated by a cam and
lever the cam being under control of the governor and either made in one piece with
the exhaust cam G or arranged to operate with G, that is when one cam is operated
the other always follows suit.
It follows, therefore, that when the engine is running above its normal speed the
cylinder always contains a combustible charge which is alternately compressed and
reexpanded, but is not ignited in consequence of not being admitted to the heated
tube L. When the speed falls the charge is always first admitted to the tube I, by
the operation of the slide, the same movement of the governor that causes the cam to
move the slide, causing the cam G to open the exhaust valve F on the next instroke
of the piston, and to close at the completion of such instroke. A fresh charge is
thus caused to be drawn in on the next outstroke, to be fired whenever the governor
may determine.
In either of the above modifications of this invention we can by suitably altering
the configuration of the exhaust cam G cause the exhaust valve F to close slightly
before the termination of the exhausting stroke of the piston either permanently or
variably according to its position as determined by the governor. The effect of this
would be to trap off a portion of the waste products in the cylinder, compress them
and reexpand them before commencing to draw in a fresh combustible charge. The
effect of this is that less of the combustible mixture is drawn into the cylinder and
thus the intensity or the quality of the charge in the cylinder can be varied.
In Figures 3 & 4 which as previously explained refers to an engine having a charge
valve of the lift type mechanically moved, M is the valve which is operated by the
cam N and lever Ŏ. This cam N is caused to operate whenever and immediately
after the exhaust cam G has lifted the exhaust valve F. To this end the two cams N
and G can be conveniently cast together and bored to slide free on the rotating
shaft H being moved longitudinally along it by means of the governor lever P as
shewn. In order to reduce the travel of the cams they are driven by a small driver Q
keyed to the shaft and consisting of a plate or collar having a single tooth or lip
B

page_text: which engages with a similar projection on the adjacent edge of the sliding cams.
It is necessary therefore only to move the cams a sufficient distance to get out of
gear with this projection which may not be more than say inch and then the work
required to be done by the governor is reduced.
In the drawings Q shews this driver keyed to the shaft and which as it has only a
single driving edge cannot fail to engage the cams in their correct position relatively
to the rotating shaft.
Although our invention is described as relating to engines capable of firing a charge
at every alternate revolution of the engine it is equally applicable to that class of
engines which draw in and expel a charge of air between each exhaust stroke and
the next charge stroke and which are capable of firing a charge once in every three
revolutions of the engine.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we hereby declare that what
we claim is :
1. In a gas motor engine having only one cylinder which serves for compression
and ignition of the combustible charge the combination and arrangement with
supplementary exhaust ports covered and uncovered by the piston of a main exhaust
port commanded by a valve under the control of a Governor in the manner and for
the purposes described.
2. In a gas Engine of the kind referred to the combination with supplementary
exhaust ports covered and uncovered by the piston, and a main exhaust port com-
manded by a valve, of means controlled by the governor whereby the main exhaust
port may be made to close so as to trap any required volume of the burnt gases in
the cylinder, substantially as described and for the purposes specified.
3. In a gas Engine of the kind referred to the combination with an exhaust valve
opened for a shorter or longer time by a cam under the control of a governor, of
another cam, either separate from or in one with the first named cam, for the purposes
of lifting the exhaust valve momentarily at the end of each working stroke substantially
as described.
4. In a gas engine of the kind described with reference to Fig. 4, wherein the
charge inlet valve is lifted mechanically, placing the cam actuating the same under
the control of the Governor in such a manner as to cause a fresh charge to he
introduced, wherever the exhaust cam has permitted the escape of burnt products,
the charge inlet cam being stepped or graduated on its opening edge, when the
exhaust cam is graduated on its closing edge, so as to admit a volume of fresh com-
hustible charge about equal to that of the burnt products expelled on the previous
instroke substantially as described.
5. In a gas engine wherein either the opening of the exhaust valve, or its moment
of closure is dependent on the action of the governor, causing the igniting apparatus
to be thrown out of operation by the governor when the charge in the cylinder is not
to be ignited substantially as described.
6. We also claim the improved Engines constructed arranged and operating sub-
stantially as described with reference respectively to Figs. 1 and 2 and Figs. 3 and
of the drawings.
TL
"