Improvements in Gas Engines.
Year: 1890

page_text: Date of Application, 30th Oct., 1890
Complete Specification Left, 30th July, 1891-Accepted, 5th Sept., 1891
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 to be as follows:-
32
23
In gas motor engines as at present constructed there is considerable loss of heat
through the sides of the cylinder from the gases of the explosion to the water
jacket, with which it is usual to surround such cylinders. There is also a great loss
of heat in the hot products of combustion leaving the engine by the exhaust pipe.
One object of this invention is to diminish these losses, and so arrange a gas or
vapour engine that at least a part of the heat so lost in existing engines is saved
and made available for the production of motive power. The invention may be
carried into effect in several ways bearing this object in view. To a gas engine of
the well known "Otto or "Beau de Rochas "cycle this invention is applied in
the following manner, which considerably modifies the action of the "Otto
cycle as commonly understood. In a cylinder, there works a piston connected by
piston rod to a crosshead, in connection with the main crank. The piston rod
passes through a cylinder cover and packing gland and the front end of the
cylinder is used as an air compressing pump: the piston takes in air from the
atmosphere and compresses it into a reservoir. This reservoir surrounds the com-
bustion chamber of the engine and the combustion chamber exterior surface within
the air reservoir has cast upon it radiating ribs which may be formed as a screw or
spiral, along the channel of which the compressed air from the pump passes and
becomes highly heated. The back end of the cylinder is used as the combustion or
power end and that end of the piston is connected to a loose piston by a piston rod
and cushion cylinder or other suitable connection.
Compressed air is admitted between the main piston and the loose piston by a
convenient valve or valves for a purpose to be hereinafter described. When the
main piston makes its exhausting stroke the compressed air between it and the loose
piston causes the loose piston to enter the combustion chamber and clear out
practically all the products of combustion. The exhaust gases preferably pass
through a regenerator constructed of perforated plates or in any other convenient
manner. A valve cuts off communication between the combustion space and the
regenerator at the required time, and another valve cuts off communication
between the atmosphere and the regenerator as required, while a third opens to the
compressed air reservoir when necessary. The general action of the engine is as
follows-On its first out stroke the cylinder is filled with air behind the piston,
and some air is compressed into the reservoir. On the return stroke or while the
crank is crossing its out centre gas is injected into the air behind the piston by means
of a suitably arranged gas pump, and this gas mixes with the air already contained in
the cylinder to form an explosive mixture which is compressed on the return stroke
into the combustion space, the loose piston yielding to the compression and leaving the
required space; it is then fired in any known manner and the explosion pressure forces
forward the motor piston on a working stroke. At the termination of that stroke the
front of the piston has compressed a portion of air into the reservoir, and on the return
or exhausting stroke the motor piston expells the exhaust gases almost entirely from
the cylinder, the loose piston being pressed forward by the compressed air which
has forced its way between it and the main piston. The exhaust gases pass through
the regenerator to the atmosphere, and the regenerator picks up a large part of the
heat of those gases which would otherwise be discharged into the atmosphere. At

page_text: or near the termination of the piston exhaust stroke, that exhaust valve is closed
which communicates between the regenerator and the atmosphere, but the valve
between the combustion space and the regenerator is kept open and the air reservoir
valve is opened. This causes compressed and heated air from the reservoir to pass
through the regenerator, and so become further heated and then enter the cylinder
and drive the piston forward, the heat imparted to it increasing its volume con-
siderably, so that its volume at the higher temperature is much greater than at the
temperature of compression as it leaves the pump or front end of the cylinder.
This gives a second power impulse and it is one characteristic feature of this inven-
tion, that with the "Otto "cycle engine an impulse is obtained at every revolution,
one impulse being given by explosion, and the next by heated air, and so power is
gained from heat which would otherwise be wasted.
The hot air is admitted to the regenerator and cylinder for a certain portion of
the forward stroke of the piston, and then cut off at the reservoir air valve, after
which the piston continues to move on under the expansive effect of the heated air
until the end of the out stroke is attained.
On the return stroke of the motor piston, after the hot air working stroke, a
portion of the air may be exhausted or not as desired but in any case gas is injected
from a gas pump and mixes with the air contained in the cylinder to form explosive
mixture which is compressed into a combustion space, the loose piston yielding to
the compression and forming a space between it and the end of the cylinder in
which combustion may take place. On explosion, which may be caused by any
known form of igniter, the first effect is to compress the loose piston still further
and so relieve the pressure of the explosion; this power, however, is given out
as the piston proceeds on its stroke, and so a more uniform pressure is kept
The piston then compresses air in front and the whole cycle as herein before
described is repeated.
up.
A water jacket is used for the air compressing end of the cylinder in order to
keep the air as cool as possible and to cause the lubrication to be effective.
The loose piston need not move with the main piston but may work in the
end of the cylinder, but in both cases a sufficient air cushion piston is adopted
to limit the motion of the loose piston without shock.
Instead of a loose piston, a mechanically driven piston may be adopted, a crank
moving at one half the revolutions of the main crank being utilized to actuate it,
or toggle gear may be adopted for the same purpose.
Eccentric or epicyclic wheel arrangements may also be used, and sometimes the
cylinder may be separated from the explosion space by a suitable valve.
In one epicyclic arrangement a pinion of a certain number of teeth is fixed con-
centrically to the crank shaft, and the crank shaft arm carries rotating with it a
toothed wheel with double the number of teeth contained by the pinion; the crank
pin is driven by this wheel, and rotates around its axis, being slightly cranked from
the centre of the wheel so that the actual throw of the crank pin is varied, and the
main piston every second revolution of the crank leaves a space at the end of
the cylinder for the explosive gases. The intermediate air charge hereinbefore
described may be utilized in slow combustion as well as explosive engines and
the gas and air may be mixed in the air pump or in the reservoir before
entering the main cylinder.
In all cases, however, the heat of the combustion chamber sides and the exhaust
gases is utilized to add to the power of the engine.
Dated this 98th day of Databor 1800
CLERK & MARKS,
13, Temple Street, Birmingham, Agents for Applicant.

page_text: עט ש VVIL
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 inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement: -
In gas motor engines as at present constructed, there is considerable loss of
heat through the sides of the cylinder from the gases of the explosion to the water
jacket, with which it is usual to surround such cylinders. There is also a great
loss of heat in the hot products of combustion leaving the engine by the exhaust
pipe. One object of this invention is to diminish these losses, and so arrange a
gas or vapour engine that at least a part of the heat so lost in existing engines is
saved and made available for the production of motive power. The invention may
be carried into effect in several ways bearing the object in view. To a gas engine
of the well known "Otto" or "Beau de Rochas" cycle this invention is applied in
the following manner, which considerably modifies the action of the "Otto" cycle
as commonly understood.
Referring to Figures 1, 2, 3, and 4 of the accompanying sheet of drawings; in a
cylinder A there works a piston C connected by piston rod to a crosshead, in
connection with the main crank. The piston rod passes through a cylinder cover A³,
and packing gland, and the front end of the cylinder is used as an air compressing
pump; the piston takes in air from the atmosphere and compresses it into a reser-
voir B, by the valves in the case B and the pipe B. This reservoir B surrounds
the combustion chamber D of the engine; and the combustion chamber exterior
surface within the air reservoir B, has cast upon it radiating ribs 13' which may be
formed as a screw or a spiral along the channel of which the compressed air of the
pump passes and becomes highly heated, or the ribs may be straight as shown in
Figures 1, 2, and 3. The back end of the cylinder A. is used as the combustion
or power end, and that end of the piston is connected to a loose piston C by a
piston rod C and cushion cylinder a or other suitable connection.
Compressed air is admitted between the main piston C and the power piston C¹
by a convenient valve or valves as C³, for a purpose to be hereinafter described.
When the main piston C makes its exhaust stroke, the compressed air between it
and the loose piston C¹ causes the loose piston to enter the combustion chamber D
as seen in Figure 2, and clear out practically all the products of combustion.
The exhaust gases preferably pass through a regenerator E, constructed of
perforated plates or in any other convenient manner. A valve cuts off communica-
tion between the combustion space and the regenerator at the required time, and
another. valve E' cuts off communication between the atmosphere and the regenerator
as required, while a third valve E opens to the compressed air reservoir when
necessary.
The general. action of the engine is as follows:--
On its first out stroke, the cylinder is filled with air behind the piston C', and some
air is compressed into the reservoir B. On the return stroke or while the crank is
crossing its out centre, gas is injected into the air behind the piston C' by
means of a suitably arranged gas pump as F2, which pump in this case is operated
by a bell crank s and groove cam G, carried on the two to one valve motion
shaft H. F and F are the gas pump valves; and this gas mixes with the air
already contained in the cylinder and combustion space D to form an explosive
mixture, which is compressed on the return stroke into the combustion space D, the
loose piston Cyielding to the compression and leaving the required space as shown
at Figure 1. The mixture is then fired in any known manner as by an igniter tube
at the aperture D¹, Figure 1, and the explosion pressure forces forward the motor

page_text: piston C on a working stroke, carrying with it the loose piston C'. At the
termination of that stroke the front of the piston C has compressed a portion of air
into the reservoir B by the valves B3, and pipe B; and on the return or exhausting
stroke the motor piston with the loose piston expels the exhaust gases almost
entirely from the cylinder, the loose piston C being forced out by the compressed
air which has forced its way between it and the main piston. The exhaust gases
pass through the regenerator E to the atmosphers by the exhaust valve E', and the
regenerator picks up a large part of the heat of those gases which would otherwise
be discharged into the atmosphere. At or near the termination of the piston exhaust
stroke, the exhaust valve E' is closed, which communicates between the regenerator
and the atmosphere, and a valve sometimes applied between the combustion
space and the regenerator is kept open, and the air reservoir valve E² is opened.
This causes compressed and heated air from the reservoir B to pass through the
regenerator E, and so become further heated and then enter the cylinder and drive
the piston Cand C forward, the heat imparted to it increasing its volume consider-
ably, so that its volume at the higher temperature is much greater than at the
temperature of compression as it leaves the pump or front end of the cylinder.
This gives a second power impulse; and it is one characteristic feature of this
invention, that with the Otto" cycle engine an impulse is obtained at every
revolution, one impulse being given by explosion, and the next by heated air, and
so power is gained from heat which would otherwise be wasted. The hot air is
admitted to the regenerator and cylinder for a certain portion of the forward stroke
of the piston, and then cut off at the reservoir air valve E, after which the piston
'continues to move on under the expansive effect of the heated air until the end of
the out stroke is attained.
On the return stroke of the motor piston, after the hot air working stroke, a
portion of the air may be exhausted or not as desired, but in any case gas is
injected from a gas pump F and mixes with the air contained in the cylinder to
form explosive mixture, which is compressed into a combustion space, the loose
piston yielding to the compression and forming a space between it and the end of
the cylinder in which combustion may take place. On explosion, which may be
caused by any known form of igniter, as an igniter tube, the first effect is to com-
press the loose piston still further and so relieve the pressure of the explosion; this
power, however, is given out as the piston proceeds on its stroke, and so a more
uniform pressure is kept up. The piston then compresses air in front and the whole
cycle as hereinbefore described is repeated.
A water jacket A' is used for the air compressing end of the cylinder in order
to keep the air as cool as possible and to cause the lubrication to be effective. A
hot projecting part C is attached to the loose piston C, and it serves to prevent
loss of heat to the water jacket A' through the loose piston C. The projection C4
is insulated by non-conducting material, and does not work in contact with the
surface of D or the cylinder A.
The exhaust valve E' is actuated from the shaft H by the lever E³ and a
suitable cam.
The air valve E is actuated by a lever E' and a grooved cain on the shaft H.
Instead of a loose piston, a mechanically driven piston may be adopted, a crank
moving at one half the revolutions of the main crank being utilized to actuate it,
or toggle gear may be adopted for the same purpose. Eccentric or epicyclic
wheel arrangements may also be used, and sometimes the cylinder may be
separated from the explosion space by a suitable valve.
Referring to Figures 5, 6, 7, 8, 9 and 10; in one epicylic arrangement a
pinion K2 of a certain number of teeth is fixed concentrically to the crank shaft,
and the crankshaft arm K carries rotating with it a toothed wheel K, with
double the number of teeth contained by the pinion K² the crank pin M is driven
by this wheel, and rotates around the axis M, being slightly cranked from the 5
centre of the wheel so that the actual throw of the crank pin M' is varied, and the

page_text: main piston C every second revolution of the crank leaves a space D at the end
of the cylinder for the explosive gases. The intermediate air charge hereinbefore
described may be utilized in slow combustion as well as explosive engines, and the
gas and air may be mixed in the air pump or in the reservoir before entering the
main cylinder.
In all cases, however, the heat of the combustion chamber sides and the exhaust
gases is utilized to add to the power of the engine.
Figure 5 is an elevation part in section showing the fixed wheel K and the
rotating wheel K with the connecting rod M in front, but the arrangement shown
in plan at Figure 6 is that preferred by me. The crank shaft K³ carries the
main crank K' and it carries the small crank by the short shaft M2. The
toothed wheel K is keyed to the shaft K which shaft is firmly fixed by key to
the engine bed as indicated so as to prevent its rotation.
The crank link K rotates round K³ and also carries a shaft M2 in line with
Min K. The toothed wheel K is keyed on to M, and so when the crank shaft b
is rotated, the crank pin M' is rotated round the centre M as well as round the
centre of K³. It thus assumes the position shown at Figures 7, 8, 9, and 10.
In Figure 7 the crank pin M' is in the position nearest the centre of K³ and the
piston C, Figure 5, is at the end of its compression stroke, leaving the explosion
space D.
The main crank K' is rotating in the direction of the arrow c in the figures,
and the wheel K rotates in the direction of the arrow d. Figure 10 shows the
position next to Figure 7 when the main crank has made its out explosion stroke.
In Figure 9 the piston C is full in again, but the end of the piston C is in the
position marked e in Figure 5, as the crank pin M¹ is at its maximum distance
from the centre K³. The next out stroke is the air expansion stroke, when the
hot air is admitted from the reservoir B by the valve E, and at the extremity of
the air expansion stroke the crank pin M¹ assumes the position shown in Figure 8.
The air in front of the piston C is thus compressed into the reservoir B at every
forward stroke, and the piston C alternately fills up the combustion space D and
leaves it free so as to perform its air stroke and explosion stroke as in the first
modification hereinbefore described. The gas pump and the valve arrangements
are the same as in Figures 1, 2, 3, and 4.
In Figures 7, 8, 9, and 10 the line M indicates the position of the connecting
rod M.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is
-
(1) In a gas engine; actuating the piston alternately by the explosion of a
compressed explosive mixture, and the expansion of air heated by the waste heat
of the explosion stroke substantially as herein before described.
(2) A gas engine in which explosion and air expansion strokes alternate with
each other, having a loose piston controlled by compressed air, which loose piston
alternately advances into and recedes from the explosion space substantially as
and for the purposes herein before described and illustrated in the accompanying
drawings.
(3) A gas engine in which explosive and air expansion strokes alternate with
each other, having a piston with variable stroke controlled by epicyclic gear, so
that the piston at the termination of each alternate stroke leaves a compression
space at one end of the cylinder substantially as and for the purposes herein before
described and illustrated in the accompanying drawings.
(4) The gas engine hereinbefore described and illustrated at Figures 1, 2, 3,
and 4 of the accompanying drawings.
(5) The gas engine hereinbefore described and illustrated at Figures 5, 6, 7, 8,
9, and 10 of the accompanying drawings.

page_text: (6) In gas engines of the kind claimed in Claim 3, the epicyclic gear herein-
before described and illustrated at Figures 6, 7, 8, 9, and 10 of the drawings.
Dated this 29th day of July 1891.
CLERK & MARKS,
13, Temple Street, Birmingham, Agents for the Applicant.