Improvements in Gas Engines.
Year: 1891

page_text: Date of Application, 28th Mar., 1891
Complete Specification Left, 28th Jan., 1892-Accepted, 5th Mar., 1892
PROVISIONAL SPECIFICATION.
Improvements in Gas Engines.
I, JOSEPH HIGGINSON, the younger, of 20 Canal Street Ancoats, Manchester,
in the County of Lancaster, Engineer, do hereby declare the nature of this
invention to be as follows:-
My invention relates to improvements in the arrangement and construction of
gas engines acting in cycles whereby an impulse is secured at every revolution of
the crank shaft, and its object is to simplify the construction of such engines and
obtain economy of gas consumption with the minimum of working parts.
In carrying my invention into effect I arrange an engine with two pistons in line
with each other connected to the same piston rod. The front piston I place in an
open ended cylinder and connect it to a crank pin by a suitable connecting rod.
The second or back piston works in a cylinder arranged tandem fashion with the
first and the piston moves with the front piston by the piston rod connecting the two.
The front cylinder serves as a pump for taking in and compressing the charge of
inflammable mixture. The second cylinder serves as a motor cylinder and the
motive impulses are applied behind the second piston while the gases in front
of the second piston are either compressed and expanded at every stroke or
alternately expelled and drawn into that end of the cylinder at each to and fro
movement. In this arrangement the acting sides of both pump and motive pistons
are the sides furthest from the crank shaft.
Unlike most gas engines the motor piston terminates its stroke in the motor
cylinder leaving but a small clearance space between the piston and the back
cover. At the side of these two cylinders is placed a third cylinder having ports,
one opening into the pump cylinder and one opening to the motor cylinder at or
near the ends of both cylinders. This side cylinder serves to contain a piston valve
or valves by which the whole valve operations of the engine are performed. The
piston valve consists of two pistons placed at a fixed distance from each other and
connected so as to move together at that fixed distance apart, the connections
being preferably made exterior to the valve cylinder in a manner hereinafter to
be described. The valve pistons are actuated from a crank pin preferably
attached to a disc on the crank shaft and piston rods or trunks of reduced diameter
pass and work through covers at both ends of the valve cylinder.
The action of the engine is as follows:-
When the pump and motor pistons are performing their "out" stroke the piston
valve is in such position that the pump port is open to the atmosphere and to
the gas supply a mixture of gas and air is thus drawn into the pump cylinder.
At the termination of the "out" stroke the valve closes this port and shortly after
the pistons by their continued movement open the pump port to the space existing
between them. The pump and motor pistons now perform their "in "stroke and
the pump piston compresses its charge into the space between the valve pistons.
Meantime the motor piston is on its "in stroke simultaneously with the pump
piston and is discharging the contents of the motor cylinder by the motor port past
the piston valve to the exhaust pipe.
"
As the "in "stroke approaches its termination the exhaust port closes, a slight
compression' takes place in the motor cylinder and the space between the valve
pistons opens on the motor port closing to the pump port. The contents of the
pump have thus been forced into the space between the two valve pistons and their
movement.has opened the space to the motor port. The compressed inflammable
charge is now ignited in any convenient known. manner and the pressure acts
upon the motor piston and propels it in its "out" stroke causing the pump to

page_text: take in a fresh charge and the piston valve to perform its various functions as
hereinbefore described. The space between the valve pistons thus serves as a
movable compression and explosion space of constant volume and the to and fro
movement of the valve pistons successively open the pump port to take in its
charge, close the pump to the atmosphere and open it to the compression space
and the second valve piston opens the motor cylinder to the exhaust pipe and
closes the port, opening to the compression space at the correct time, closing the
compression space to the pump cylinder before or soon after opening it opens to
the motor port. In this simple manner I arrange the to and fro movement of a
piston valve to perform all the valve actions necessary to enable the pump to take
in and compress its charge and the motor piston to receive an impulse at every
revolution and exhaust the products of combustion. The piston valve may be
arranged to open the gas ports as well as the air port but I prefer to apply a
separate gas valve to this work and control that valve by the action of the governor.
Although the ignition may be effected in any convenient manner yet I prefer to
cause the piston valve to control the ignition as well as the other functions of the
engine this I perform by attaching an igniting tube to open to the motor port and
arrange that the exhaust compression in the motor cylinder is a little less than
the compression of the mixture in the space between the valve pistons and so when
these pistons open to the motor port a portion of the mixture rushes into the port
and enters the igniter tube and so causes the explosion. Although I prefer to ignite
directly in the motor cylinder port yet I may arrange a special igniter port which
is uncovered at the proper time by the piston valve, and so allows the mixture
access to an incandescent igniter tube which brings about the explosion.
I
The stroke of the piston valve is preferably made long and the pistons are of
considerable diameter in order to allow of a very large port opening between the
compression space and the motor cylinder. By this precaution loss of heat is
avoided which would occur if the port were small.
To connect the two valve pistons together I attach lugs or saddles to the pro-
jecting trunks, and link them together by pins and bolts which bolts between
pass
the lugs outside the cylinder and so permit the pistons to move together when one
of them is driven by a connecting rod actuated from a separate crank pin. I prefer
this external mode of attaching the pistons to any internal method as the
presentation of cooling surfaces to the ignited mixture within the compression space
is avoided.
Instead of arranging my pump and motor cylinders tandem fashion I
may place
them side by side and actuate their respective pistons by separate crank pins and
connecting rods and in this case I arrange the valve cylinder with its valve pistons
between the two cylinders but I may also place the valve cylinder at right angles
to the pump and motor cylinders when separate side by side cylinders are used and
drive the piston valve by means of a second motion shaft actuated from the engine
shaft by suitable gearing. Instead of tandem pistons coupled together by a piston
rod I may also form the air pump by a piston of larger diameter than the motor
which will then be a continuous trunk piston and the pistons will fit and work in
cylinders of two diameters so that the annular space surrounding the motor trunk
forms the pump. The piston valve in this case would be arranged as in the first
modification I have herein described.
In some cases I allow the pump to discharge a portion of its contents to the
compression space between the valve pistons by means of a lift valve in order to
more completely discharge the compressed charge contained by it.
In another modification of engine using the piston valve herein described and
adopting an alternate explosion and hot compressed air impulse as described in my
Specification No. 17371 of 1890 I cause the front end of the motor piston to
alternately compress air and gas into the moving space between the valve pistons
and compress air into a reservoir surrounding the explosion space and I fire the
mixture every second revolution on the outward stroke and obtain an explosion
impulse while I admit hot air under considerable pressure from the reservoir on the

page_text: other out stroke and so obtain alternate explosion and hot air impulses. In this
case I do not use a front cylinder but only a guide and crosshead.
To relieve the compression space of exhaust gases which would otherwise be
confined I sometimes cause the motor piston to overrun a port in the engine cylinder
to discharge the contents of cylinder and space before the valve moves to close
the space and open the exhaust, but I may use a discharge valve from the compression
space for the same purpose.
By adding a separate cylinder to the modifications of engine herein before described
in which I obtain an explosion impulse at every revolution I sometimes give a hot
air impulse at each revolution, also, the hot air being supplied by compressing air
at front end of the motor piston into the air jacket which air is thus heated by the
waste heat of the engine and is utilized to give an impulse at every revolution.
In an engine of this modification four impulses would be given per revolution,
two explosion and two hot air.
Dated this 96th day of March 1891
MARKS & CLERK,
13, Temple Street, Birmingham, Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in Gas Engines.
1, JOSEPH HIGGINSON, the younger, of 20 Canal Street, Ancoats, Manchester,
in the County of Lancaster, 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 relates to improvements in the arrangement and construction of
gas engines acting in cycles, whereby an impulse is secured at every revolution of
the crank shaft, and its object is to simplify the construction of such engines and
obtain economy of gas consumption with the minimum of working parts.
Referring to the two accompanying sheets of drawings Figures 1 to 20 inclusive
illustrate the various applications of my invention in different views and sections.
Throughout the drawings, the same or similar letters are used to indicate the
same or similar parts.
In carrying ny invention into effect, I arrange an engine with two pistons
respectively A, B, Figures 1, 2, 3, and 4 in line with each other connected to the
same piston rod C. The front piston A, I place in an open ended cylinder A' and
connect it to a crank pin by a suitable connecting rod. The second or back piston B
works in a cylinder B arranged tandem fashion with the first and the piston moves
The first cylinder A¹
with the front piston by the piston rod connecting the two.
serves as a pump for taking in and compressing the charge of inflammable mixture.
The second cylinder B' serves as a motor cylinder and the motive impulses are
applied behind the second piston B while the gases in front of the second piston are
either compressed and expanded at every stroke or alternately expelled and drawn
into that end of the cylinder at each to and fro movement by way of a port such
as B. In this arrangement the acting sides of both pump and motor pistons
respectively A and B are the sides furthest from the crank shaft.
Unlike most gas engines, the motor piston terminates its stroke in the motor
cylinder B leaving but a small clearance space between the piston and the back
cover D.
At the side of these two cylinders is placed a third cylinder E having
ports E', E2, one E opening into the pump cylinder A', and one E' opening to the
motor cylinder B' at or near the ends of both cylinders. This side cylinder E
serves to contain a piston valve or valves. F, F' by which the whole valve operations
of the engine are performed. The piston valve consists of two pistons F, F
placed at a fixed distance from each other, and connected so as to move together at

page_text: that fixed distance apart, the connections being preferably made exterior to the
valve cylinder in a manner hereinafter to be described. The valve pistons
are actuated from a crank pin G preferably attached to a disc G on the crank
shaft, and piston rods or trunks of reduced diameter F2, F3 pass and work through
covers at F, F' both ends of the valve cylinder.
i
The action of the engine is as follows:
When the pump and motor pistons A, B, are performing their "out" stroke,
that is, towards the crank shaft, the piston valve F, F' is in such position that the
pump port E2 is open to the atmosphere and to the gas supply; a mixture of gas
and air is thus drawn into the pump cylinder A behind the piston A. At the
termination of the out stroke, the valve closes this port E2 and shortly after the
pistons by their continued movement open the pump port E² to the space existing
between them. The pump and motor pistons now perform their "in" stroke and
the pump piston A compresses its charge into the space between the valve
pistons F, F. Meantime the motor piston B is on its "in" stroke simultaneously
with the pump piston A and is discharging the contents of the motor cylinder B
by the motor port.E' past the smaller diameter F3 of the piston valve F¹ to the
exhaust pipe . As the "in" stroke approaches its termination the exhaust port
closes E', a slight compression takes place in the motor cylinder B₁ between the
piston B and the cover D and the space between the valve pistons F, F' opens on
the motor port E' closing to the pump port E2. The contents of the pump have
thus been forced into the space between the two valve pistons F, F and their
movement has opened the said space to the motor port. The compressed inflammable
charge is now ignited in any convenient known manner, and the pressure acts upon
the motor piston B₁ and propels it on its "out" stroke causing the pump piston A
to take in a fresh charge and the piston valve F, F' to perform its various functions
as hercinbefore described. The space H between the valve pistons F, F¹ thus
serves as a movable compression and explosion space of constant volume, and the
to and fro movement of the valve pistons F, F¹ successively open the pump port E³
to take in its charge, close the pump to the atmosphere and open it to the
compression space H, and the second valve piston opens the motor cylinder to
the exhaust pipe and closes the port, opening to the compression space at the
correct time, closing the compression space H to the pump cylinder A¹ before or
soon after opening it to, the motor port. In this simple manner I arrange the to
and fro movement of a piston valve to perform all the valve actions necessary to
enable the pump to take in and compress its charge, and the motor piston to receive
an impulse at every revolution and exhaust the products of combustion. The
piston valve F, F' may be arranged to open the gas ports as well as the air port,
but I prefer to apply a separate gas valve to this work and control that valve by the
action of the governor. The gas valve and its arrangements are illustrated at
Figures 5, 6, 7 and 8.
Figure 5 shows the port E² opening to a cavity E3 by small holes E. Figure 5
is a sectional plan as in Figure 2 but on a larger scale.
Figure 6 is a longitudinal vertical section showing the port E² with the gas
holes E leading to the cavity E3. The gas valve I is inserted in an aperture
leading to E3 and supplied with gas by a pipe I³.
The gas valve stem I' is operated as shown at Figures 7 and 8. Figure 7 is a
plan and Figure 8 is a side elevation. The levers K, K' actuate the valve stem I¹
being connected by a rocking shaft, and the lever Kis operated by the bell crank
lever M, M which is in its turn actuated by the pin M2 carried by the reciprocating
rod which is one of the connecting links connecting the valve pistous F, F. The
lever M actuates the lever K' through the knife edge L which is raised by the
governor as shown in dotted lines.
Although the ignition may be effected in any convenient, manner yet I prefer to
cause the piston valve to control the ignition as well as the other functions of the
engine; this I perform by attaching an igniting, tube. N' to open to the motor port,

page_text: and I arrange that the exhaust compression in the motor cylinder is a little less than
the compression of the mixture in the space between the valve pistons, and so when
these pistons open to the motor port a portion of the mixture rushes into the port
and enters the ignition tube and so causes the explosion. Although I prefer to
ignite directly in the motor cylinder port, yet I may arrange a special igniter port
as N Figures 1, 2, 3, and 4 which is uncovered at the proper time by the piston
valve F, and so allows the mixture access to an incandescent igniter tube N' which
brings about the explosion.
The stroke of the piston valve F, F is preferably made long, and the pistons F, F¹
are of considerable diameter in order to allow of a very large port E' opening between
the compression space and the motor cylinder. By this precaution loss of heat is
avoided which would occur if the port were small.
To connect the two valve pistons F, F together, I attach lugs or saddles O, O'
to the projecting trunks F, F and link them together by pins and bolts f, which
bolts/pass between the lugs outside the cylinder and so permit the pistons to
move together when one of them is driven by a connecting rod actuated from a
separate crank pin G. I prefer this external mode of attaching the pistons to any
internal method as the presentation of cooling surfaces to the ignited mixture
within the compression space is avoided.
Crossbars P, Q, are preferably attached to the lugs O, O' so as to connect the
pistons F, F in a flexible manner.
In the sectional plans, Figures 2, 3 and 4, I have shown three positions of the
engine, and Figures 1 and 9 illustrate the corresponding positions of the cranks.
In Figures 1 and 2, the main crank is full in and the piston B is at the in end of its
stroke. The piston F' has just closed the port E' from connection with the exhaust
pipe g and is just opening the port E' to the space H between the pistons.
In Figure 3 the piston B has travelled a short portion of its forward stroke and
the port E' is full open to the space H so that the explosion pressure from H can
freely pass to the cylinder B behind B.
In Figure 4 the space H has closed to the port E' and is opened by the piston F.
to the port E2 so that the pump piston A is compressing its charge into the
space H.
In Figure 3 the air and gas charge enters behind the piston A simultaneously
with the working pressure acting on B.
At Figure 9, 3 indicates the position of the main and valve cranks corre-
sponding to the plan Figure 3. a is the main crank centre and the valve crank
centre.
4 indicates the positions corresponding to Figure 4 and the crank centres are
similarly lettered.
Instead of arranging my pump and motor cylinders tandem fashion. I may place
them side by side as shown at Figures 10, 11, 12 and 13 and actuate their respective
pistons A and B by separate crank pins and connecting rods, and in this case I
arrange the valve cylinder E with its valve pistons F; F between the two
cylinders A' and B', but I may also place the valve cylinder E at right angles to
the pump and motor cylinders when separate side by side eylinders are used, and
drive the piston valve by means of a second motion shaft R actuated from the
engine shaft by suitable gearing. Instead of tandem pistons coupled together by a
piston rod I may also form the air pump (see Figure 14) by a piston A of larger
diameter than the motor B which will then be a continuous trunk piston, and these
pistons will fit and work in cylinders A', B' of two diameters, so that the annular
space surrounding the motor trunk forms the pump. The piston valve in this case
would be arranged as in the first modification have herein described.
In some cases I allow the pump to discharge a portion of its contents to the
compression space between the valve pistons F, F' by means of a lift valve in order
to more completely discharge the compressed charge contained by it.
Figure 10 is a sectional plan of a side by side cylinder engine, while Figure. 11
is a transverse section,

page_text: igure 12 is a sectional plan of another side by side cylinder engine, and Figure 13
is an end external elevation.
Figure 14 is a sectional plan of the annular piston engine.
In all these modifications of my invention the action is the same as hereinbefore
described with reference to the Figures 1, 2, 3, 4, 5, 6, 7, 8, 9 and the respective
parts will be readily recognised by the similar lettering.
In another modification of engine using the piston valve herein described and
adopting an alternate explosion and hot compressed air impulse as described in my
Specification No. 17371 of 1890, I cause the front end of the motor piston B, see
Figures 15, 16, 17, 18, and 19, 15, 16, 17, and 18 to alternately compress air
and gas into the moving space H between the valve pistons F, F' and compress air
into a reservoir U surrounding or adjoining the explosion space, and I fire the
compressed mixture in the space H on every second revolution on the outward
stroke, and obtain an explosion impulse while I admit hot air under considerable
pressure from the reservoir U on the other out stroke and so obtain alternate
explosion and hot air impulses. In this case I do not use a front cylinder, but
only a guide and crosshead.
To relieve the compression space of exhaust gases which would otherwise be
confined, I sometimes cause the motor piston B to overrun a port in the engine
cylinder to discharge the contents of cylinder and space before the valve moves to
close the space and open the exhaust, but I may use a discharge valve from the
compression space for the same purpose. The action is clearly shown at
Figures 15, 16, 17 and 18 while Figures 15, 16, 17, and 18 show the corre-
sponding positions of the main and valve cranks. In Figure 15 the piston B is
beginning its out air stroke and hot air from the chamber U is being admitted by
the valve U to the cylinder. The previous forward stroke has compressed a
charge of air from the front side of the piston B by the valve V' and pipe V to the
air chamber U at a considerable pressure. Here the air is heated by waste heat
from the explosion and the hot air is admitted by the valve U operated by the
lever U. The lever U2 is struck from a connection to the piston F
The pistons F, F are driven from a crank pin G in the toothed wheel S¹
(Figure 15) which wheel gears into the wheel S of half its diameter, so that the
pistons F, Fl only make half the number of strokes as the piston B.
In Figure 15 air is being compressed by way of the port E' into the space H and
a gas pump T (Figures 15 and 19) is simultaneously forcing gas into H with the air
by the pipe T¹.
In Figure 16 the piston B has completed its out stroke and is about to return;
the space H is closed to E' and the exhaust port W in the piston F' is open to E¹.
The space H is filled with compressed explosive mixture.
In Figure 17 the space H is open to the port E' and explosion has just occurred,
so that the piston B is just beginning its explosion stroke. The port E² is closed
during this stroke as shown by Figure 18 where B has completed its out stroke
compressing air into the chamber U by the valve V. The front of the cylinder B¹
is thus charged with air at every stroke and the charge is alternately compressed
in to the space. H and chamber U.
In Figures 15, 16, 17, 18, a is the main crank pin and b is the valve and
gas pump crank pin, and the positions correspond to the corresponding sectional
plans.
Figure 20 is a longitudinal section and cross section showing another method of
connecting the pistons F and F by cast segments c, d fitting the cylinder.
By adding a separate cylinder to the modifications of engine hereinbefore
described in which I obtain an explosion impulse at every revolution, I sometimes
give a hot air impulse at each revolution, also, the hot air being supplied by compressing
air at front end of the motor piston into the air jacket, which air is thus heated by
the waste heat of the engine and is utilized to give an impulse at every revolution.
In an engine of this modification four impulses would be given per revolution,
two explosion and two hot air.

page_text: Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
(1) A gas engine having three cylinders; respectively, pump motor and valve
cylinders, in which two coupled valve pistons with a combustion space between them,
having a simple reciprocating motion, control-the admission to the pump; the
discharge from the pump to the combustion space; the exhaust from the motor
cylinder and the admission of the explosion pressure to the motor cylinder
substantially as and for the purposes herein before described.
(2) A gas engine constructed and arranged substantially as hereinbefore
described with reference to Figures 1 and 2 of the accompanying drawings.
(3) A gas engine having side by side pump and motor cylinders and central
valve cylinder constructed and arranged substantially as hereinbefore described
with reference to Figures 10 and 11 of the drawings.
(4) A gas engine having side by side pump and motor cylinders and transverse
valve cylinder, constructed and arranged substantially as hereinbefore described
with reference to Figures 12 and 13 of the drawings.
(5) A gas engine as claimed in Claim 1 with annular pump cylinder as in
Figure 14 of the accompanying drawings.
(6) A gas engine having, a combined motor and pump cylinder a valve cylinder
in which the valve pistons make half the number of strokes of the main piston and
an air reservoir and valves; the engine being arranged for alternate hot air and
explosion impulses substantially as hereinbefore described and illustrated with
reference to Figures 15, 16, 17, and 18 of the drawings.
Datad this 97th day of January 1900
MARKS & CLERK,
13, Temple Street, Birmingham, Agents for the Applicant.