Improvements in Gas Engines.
Year: 1892

page_text: Date of Application, 11th Jan., 1892
Complete Specification Left, 11th Nov., 1892-Accepted, 17th Dec., 1892
PROVISIONAL SPECIFICATION.
Improvements in Gas Engines.
I, JOSEPH HIGGINSON, the younger, of 9 Wharf Street, Ancoats, in the City
of Manchester, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in the action, construction and arrangement
of gas engines, and it comprises; an engine in which a single acting open ended
cylinder with a trunk piston is used as the power cylinder, and the piston receives
an impulse at every forward stroke, exhausting on every back stroke, the valve
actions being performed in the main by a pair of moving pistons in a second cylinder
and the compression of the mixture occurring in the said cylinder; an engine of
similar arrangement, but with the various ports and the second cylinder so devised
that a compounding effect is produced, and the gases from the explosion cylinder
pass at a certain period of the stroke to the second cylinder, and are there expanded
to an extent sufficient to fully utilize the power of the explosion; an engine in
which a pump supplies mixture to a side or end cylinder under compression between
two pistons, the space between the pistons forming the compression or explosion
space and the pistons perform the valve actions of the engine, eccentrics being
adapted to enable the valve motions to be reversed so as to reverse the engine.
In constructing a gas engine to carry into effect the first part of my invention I
arrange an open ended power cylinder with a trunk piston and cause the piston to
sweep the whole cylinder leaving the minimum of mechanical clearance at the end
of the piston stroke, I connect the closed end of the cylinder by a large and short
port with a second cylinder. In the second cylinder I place two pistons coupled
together with a space between them equal to the space required for compression,
and I drive these pistons by piston rod and crosshead from a crank set at about
right angles to the main crank, the piston rod passing through a cylinder cover set
in front of the second cylinder. The front part of the second cylinder I use as a
compression pump for gas and air, and I admit the charge by a suitable gas and
air inlet valve, and discharge from the pump to the space between the pistons, at
the required time, through an automatic lift valve opening into the space between
the pistons, and uncovered by one of the pistons as the stroke proceeds. When the
space between the moving pistons is filled with explosive mixture under compression,
the return movement opens the said space to the large port hereinbefore described,
and the mixture is then fired. The explosion pressure acts on the motor piston and
propels it outward, and the opening of the port is so proportioned that the explosion
space is open to the power cylinder during the whole forward stroke, and at the
end of the forward stroke the cylinder exhausts down to atmospheric pressure by a
port in the motor cylinder. The two pistons then move so that the space between
them closes to the power cylinder, and the back piston opens the large port to an
exhaust port, through which port the contents of the power cylinder are discharged
into the atmosphere on the return stroke. The side cylinder with two pistons and
the lift valves indicated, serves as compressing pump and movable explosion space,
while the back piston serves the purpose of an exhaust valve. Instead of com-
pressing at the front and exhausting behind the second cylinder the compression
could be arranged to occur behind, and the exhausting operation in front.
In an engine constructed in accordance with the second part of my invention I
arrange two cylinders as in the modification hereinbefore described, but I use the
back end of the second cylinder for compressing and charging pump, and the front
end for expanding from the main cylinder by compounding; while the space between
the two pistons is used for explosion and compression space as already described.

page_text: I arrange two ports, however, to lead from the main cylinder to the second, one
large port at the end, and another large port run over by the main piston after
mid-stroke, and entering the second cylinder close to the front cover.
I also form a pocket in the side of the main piston to run over the middle port
about half stroke back, communicating with atmosphere.
The action is as follows:-The charge is taken into the back end of the second
cylinder and compressed. into the space between the two pistons; then the said
space is opened to the main cylinder by the large port and the mixture fired. The
main piston proceeds on its stroke under the pressure of the explosion, and when a
little past half stroke the second or mid port is overrun and the pressure reduced
by expansion, passes through the port to the front end of the second cylinder acting
on the piston then at the front end of its stroke, and propelling it in aid of the
main piston, the expansion into the second cylinder continues during the rest of the
out stroke of the main piston, and about half of the return stroke, when the second
piston arrives at or near the end of its working stroke. The main piston exhaust
pocket then covers the mid port opening to atmosphere, and the main piston
discharges its contents through the large end port, now uncovered by the front
second cylinder piston, to the atmosphere by the main piston pocket or recess. This
recess remains open till the second piston also discharges its contents through the
main piston; meantime the work of charging and compressing has proceeded at
the back end of the second cylinder, and between the pistons, so that another
compressed charge is ready to be ignited to give another impulse.
The second cylinder in this modification is made of greater diameter or larger
capacity than the first so as to accomplish the required amount of expansion. The
volume of charge taken in at one end is proportioned by cutting off during admission,
or blowing through a port for part of the compression stroke to give the desired
volume and pressure of combustible mixture at the time required.
In a third modification of my invention I use the side cylinder with its two
pistons, as valve and compression space cylinder only, and compress the mixture
between the pistons by a separate pump, but I so arrange the valve pistons that
the engine may be made reversible. To accomplish this I actuate the coupled
pistons, which are of the same diameter and entirely balanced, by means of either
of two eccentrics arranged with link reversing motion of any usual type, or I actuate
by a single eccentric with a lever adapted to allow movement of the connecting rod
or strap to opposite sides of the fulcrum. I may also use radial valve gear without
eccentric and reverse in any well known manner common to radial gear for steam
engines.
Suitable rocking shafts and levers may be used to make connection between the
eccentrics and valve pistons.
In modifications where I use a moving explosion or compression space I some-
times delay the opening of the explosion space to the cylinder for a part of the
stroke, and admit compressed air heated by the waste heat to give a part of the
stroke due to the expansion of the air and I fire into the air by the flame of
the explosion.
In the modifications of my invention hereinbefore described any known igniting
arrangements may be used but I prefer the tube igniter, and I adopt piston and
lift valves when valves are required, although slide valves may also be used without
departing from the essential features of my invention, which essential features lie
in the cycles of operation herein before described, whereby a moving explosion space
is formed between two connected pistons and one side of one of the said pistons acts
as compressing pump.
Dated this 9th dow of Inmun 1000

page_text: COMPLETE SPECIFICATION.
Improvements in Gas Engines.
I, JOSEPH HIGGINSON, the younger, of 9 Wharf Street, Ancoats, in the City
of Manchester, 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 action, construction and arrange-
ment of gas engines, and it comprises-an engine in which a single acting open ended
cylinder with a trunk piston is used as the power cylinder and the piston receives
an impulse at every forward stroke, exhausting on every back stroke, the valve
actions being performed in the main by a pair of moving pistone in a second
cylinder and the compression of the mixture occurring in the said cylinder; an
engine of similar arrangement but with the various ports and the second cylinder
so devised that a compounding effect is produced and the gases from the explosion
cylinder pass at a certain period of the stroke to the second cylinder and are
there expanded to an extent sufficient to fully utilize the power of the explosion.
Referring to the two sheets of drawings accompanying
Figure 1 is an external elevation of an engine constructed in accordance with my
invention looking on the low pressure or valve cylinder.
Figure 2 is a transverse section on the line V, W, Figure 1.
Figure 3 is a sectional plan.
Figure 4 is a transverse section on the line x, y.
Figure 5 is a valve action diagram for the motor or high pressure cylinder.
Figure 6 is a similar diagram for the valve or low pressure cylinder.
In constructing a gas engine to carry into effect the first part of my invention
I arrange an open ended power cylinder A (Figures 1, 2, 3 and 4) with a trunk
piston Band cause the piston to sweep the whole cylinder leaving the minimum of
mechanical clearance at the end of the piston stroke, I connect the closed end of
the cylinder by a large and short port H with a second cylinder C. In the second
cylinder C I place two pistons D, D' coupled together with a space E between
them equal to the space required for compression, and I drive these pistons by
piston rod R and crosshead from a crank S set at about right angles to the main
crank T, the piston rod R passing through a cylinder cover set in front of the
second cylinder C. The front part G of the second cylinder I sometimes use as a
compression pump for gas and air, but in the drawings I have shown the back
part F so used, and I admit the charge by a suitable gas and air inlet valve Q
Figure 2, and discharge from the pump end F to the
at the required time, through an automatic lift valve between the pistons
opening into the space
between the pistons and a port F¹ uncovered by one of the pistons D as the
back stroke proceeds. Instead of controlling the port F by a lift valve I may
use a positively actuated piston valve as at Figures 1 and 2, O. When the space. E
between the moving pistons is filled with explosive mixture under compression, the
return movement closes the port F' and opens the said space E to the large port H
hereinbefore described and the mixture is then fired.
The explosion pressure acts on the motor piston B which is then at the
beginning of its stroke and propels it outward, and the opening of the port H
8 so proportioned that the explosion space E is open to the power cylinder
luring the whole forward stroke of the piston D, and at the end of the forward
troke the cylinder exhausts down to atmospheric pressure by a port in the motor.
ylinder crossed by the piston B at the out end of its stroke.
This port is not shown in the drawings, but such ports are well understood. The
wo pistons D, D' then move so that the space E between them closes to the power
ylinder A and the front piston opens the large port H to an exhaust port in the
ront end G of the cylinder C, through which port the contents of the lower

page_text: cylinder A are discharged into the atmosphere on the return stroke. The side
cylinder C with two pistons and the lift valves or piston valve indicated serves as
compressing pump and movable explosion space while the front piston serves the
purpose of an exhaust valve. Instead of compressing at the back and exhausting
in front of the second cylinder the compression could be arranged to occur in front
and the exhausting operation behind.
In Figures 1, 2, 3 and ports are shown which are not required for the action
hereinbefore described; these ports are required for carrying out the second part
of the invention hereinafter described.
In an engine constructed in accordance with the second part of my invention I
arrange two cylinders A and C (see Figures 1, 2, 3 and 4) as in the modification
hereinbefore described, and I use the back end F of the second cylinder C for
compressing and charging pump, and the front end G for expanding from the main
cylinder A by compounding while the space E between the two pistons D, D¹
is used for explosion and compression space as already described. I arrange two
ports H, I, however, to lead from the main cylinder A to the second C, one large
port H at the end and another large port I, run over by the main piston B after
mid stroke, and entering the second cylinder C close to the front cover as shown in
Figure 3.
also form a pocket B' in the side of the main piston B to run over the middle
port I about half stroke back, communicating with atmosphere by the exhaust
port K (Figure 3).
The action is as follows-The charge is taken into the back end F of the second
cylinder C and compressed into the space E between the two pistons D, D'; then
the said space E is opened to the main cylinder A by the large port H and the
mixture fired. The main piston B proceeds on its stroke under the pressure of the
explosion, and when a little past half stroke the second or mid port I is overrun
and the pressure reduced by expansion passes through the port I to the front
end G of the second cylinder C acting on the piston D then at the front end of its
stroke, and propelling it in aid of the main piston B, the expansion into the second
cylinder C continues during the rest of the out stroke of the main piston B and
about half of the return stroke, when the second piston arrives at or near the end
of its working stroke. The main piston exhaust pocket B' then covers the mid
port I opening to atmosphere by way of K, and the main cylinder A. discharges its
contents through the large end port H, now uncovered by the front second cylinder
piston D' to the atmosphere by the main piston pocket or recess B¹. This
recess B' remains open till the second piston D¹ also discharges its contents through
the main piston pocket B'; meantime the work of charging and compressing has
proceeded at the back end F of the second cylinder C and between the pistons D, D'
so that another compressed charge is ready to be ignited to give another impulse
when the space E again opens to the port H.
The second cylinder C in this modification is made of greater diameter or larger
capacity than the first A so as to accomplish the required amount of expansion.
The volume of charge taken in at one end is proportioned by cutting off during
admission or blowing through a port for part of the compression stroke to give the
desired volume and pressure of combustible mixture at the time required.
The piston valve O shown in dotted lines in Figures 1 and 3 operates in the
cylinder shown in cross section at P Figure 2. The valve may be driven by an
eccentric but I prefer to actuate it by means of a cam U on the crank shaft,
a lever V, link L, levers L, L, cross shaft N and link M.
The spring W operates the piston valve O in one direction while the cam
operates it in the other; that is, the spring W keeps the cam roller on the lever V
at all times against the surface of the cam U. The piston valve O is so arranged
and so actuated by its cam that on the inlet or charging stroke of the piston D,
gas and air passes from the mixture valve Q by the ports a and d into the end F
of the cylinder C, when the piston D returns compressing the charge, the port a
leading to the valve Q is closed and the port F' is opened by way of a chamber in

page_text: the piston valve to the port d, so that the charge is compressed into the space
between the pistons.
The port is intended to discharge the exhaust gases from the space E by way
of the piston valve O and the port b.
When the engine is governing the gear operates to hold the lever V back and
to keep the piston valve to one extreme of its stroke so that the port F1 is kept
closed and the charge is compressed through d by way of c to a large chamber and
so impulses are missed till the speed falls. A suction valve is arranged to open
into A to prevent loss of power by the formation of a vacuum.
In Figure 5 the arrow 1 shows the out stroke on the piston B while the arrow 2
shows the instroke; at the point 3 on the out stroke the admission to the low
pressure cylinder begins; at the point 4 on the in stroke the exhaust opens.
In Figure 6 the arrow 5 shows the exhausting stroke and 6 the expanding stroke
of the piston D¹.
The various points of opening and closing valves are indicated on the drawing.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is―
1. A gas or like engine, in which-two pistons are connected together to
produce a space between them for compression and explosion, one of the pistons
is used to take in the charge and compress it into the space; and the pistons
being moved together allow the explosion to act on the motor piston at every
revolution of the crank, substantially as and for the purposes hereinbefore described
and illustrated in the accompanying drawings.
2. A compound gas or like engine in which-two pistons are connected together
to produce a space between them for compression and explosion; one of the pistons
is used to take in the charge and compress it into the space; and the other piston
is used to expand the hot gases from the high pressure cylinder giving an impulse
at every revolution in the high pressure cylinder and also an impulse at every
revolution in the low pressure cylinder, substantially as and for the purposes
herein before described and illustrated in the accompanying drawings.
3. A gas or like engine arranged as hereinbefore described and as illustrated in
Figures 1, 2, 3, and 4 of the accompanying drawings.
Dated this 10th day of November 1909
MARKS & CLERK,
13, Temple Street, Birmingham, Agents for the Applicant.