Year: 1887

page_text: Date of Application, 23rd Aug., 1887
Complete Left, 2nd May, 1888
Complete Accepted, 8th June, 1888
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane, in
the County of Middlesex, Consulting Engineer and Patent Agent, do hereby declare
the nature of this invention to be as follows :-
This invention relates to that description of gas motor engine in which the firing of
a combustible charge takes place once in every four strokes of the piston, such as that
known as the "Otto" engine.
The present improvements have for their object to produce a greater development of
power by the formation in the cylinder of an explosive mixture rich in gas and free
from products of combustion, and also to produce an increased useful effect and saving
in gas consumption by the expansion of the products of combustion.
For this purpose, the engine is so arranged that at the end of the expelling stroke
the portion of the gaseous products of combustion which would otherwise remain in
the cylinder, are expelled more or less entirely therefrom by the introduction of
atmospheric air, to which charge of air is afterwards admitted either pure combustible
gas or a mixture of gas and air, the supply being cut off before the end of the suction
stroke.
By this means, on the following compression and working strokes a high degree of
expansion, and consequently an increased useful effect, is obtained.
The power of the engine may be varied according as a greater or less quantity of
combustible gas or gaseous mixture is admitted to the air in the cylinder, and according
as the charge is admitted during a greater or less part of the suction stroke, so as to
vary the degree of expansion.
In constructing the gas motor engine for operating in the above described manner,
the front end of the engine cylinder is closed and is provided with a suction and

page_text: delivery valve communicating respectively with the atmosphere and with a closed
reservoir, so that at each forward stroke of the piston a charge of air is forced thereby
at a certain pressure into the reservoir. A pipe leads from this reservoir to the back
end of the cylinder where it is provided with a valve, and where it communicates with
the inlet passage of the cylinder, also governed by a valve, both these valves
being actuated by cams on a way shaft revolving at half the speed of the engine
shaft.
These valves are opened when the piston arrives near the end of its expelling
instroke, so that the compressed air can then pass from the reservoir into the cylinder,
expelling the remainder of the products of combustion through the open escape valve
as the piston completes its instroke, at the end of which the air in the reservoir will
have sunk to about atmospheric pressure. The escape valve being now closed, the
piston commences its suction stroke, and the valve of a gas pipe leading into the
inlet passage being more or less opened, gas together with a greater or less proportion
of air admitted by the air reservoir valve, is drawn into the charge of air contained
in the cylinder.
When the piston has performed a certain part of its outstroke, the gas and air
valves are closed, so that as the piston completes its stroke the combustible charge in
the cylinder is expanded below atmospheric pressure. At the commencement of the
following instroke the combustible charge will first again attain atmospheric pressure
and will then be compressed to a greater or less degree on the completion of such
stroke.
Thus according as the supply of gas and air has been cut off at an carlier or later
period of the outstroke, a smaller or greater compressed charge will be contained in
the cylinder at the end of the compression instroke, which, on being fired, will operate
with a greater or less degree of expansion. If the cut off and expansion be made
unalterable, the regulation of the speed of the engine is effected by acting upon the
gas valve by means of a sliding cam with incline, which is actuated by the governor.
The regulation may, however, be effected both by controlling the gas supply and by
varying the cut off.
The ignition of the charge can be effected in any known manner.
Instead of
combustible gas, combustible vapour or spray may be employed, and the engine, which
may be either horizontal, vertical or inclined, may have one or more working
cylinders.
Dated this 221 day of Inout 1007

page_text: vapour, or Spray and Air.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane, in
the County of Middlesex, Consulting Engineer, and Patent Agent, 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 that description of gas motor engine in which the firing of
a combustible charge takes place once in every four strokes of the piston such as that
known as the Otto engine.
The present improvements have for their object to produce a greater development
of power by the formation in the cylinder of an explosive mixture rich in gas and free
from products of combustion, and also to produce an increased useful effect and saving
in gas consumption by the expansion of the products of combustion.
For this purpose, the engine is so arranged that at the end of the expelling
stroke the portion of the gaseous products of combustion which would otherwise
remain in the cylinder, are expelled more or less entirely therefrom by the intro-
duction of atmospheric air, to which charge of air is afterwards admitted either pure
combustible gas or a mixture of gas and air, the supply being cut off before the
end of the suction stroke.
By this means, on the following compression and working strokes a high degree
of expansion and consequently an increased useful effect is obtained. The power of
the engine may be varied according as a greater or less quantity of combustible gas
or gaseous mixture is admitted to the air in the cylinder and according as the
charge is admitted during a greater or less part of the suction stroke so as to
vary the degree of expansion.
In constructing the gas motor engine for operating in the above described
manner, the front end of the engine cylinder is closed and is provided with a suction
and delivery valve communicating respectively with the atmosphere and with a
closed reservoir, so that at each forward stroke of the piston a charge of air is
forced thereby at a certain pressure into the reservoir.
A pipe leads from this reservoir to the back end of the cylinder where it is
provided with a valve, and where it communicates with the inlet passage of the
cylinder also governed by a valve, both these valves being actuated by cams on a
way shaft revolving at half the speed of the engine shaft.
These valves are opened when the piston arrives near the end of its expelling
instroke so that the compressed air can then pass from the reservoir into the cylinder,
expelling the remainder of the products of combustion through the open escape valve
as the piston completes its instroke at the end of which the air in the reservoir will
have sunk to about atmospheric pressure. The escape valve being now closed the
piston commences its suction stroke, and the valve of a gas pipe leading into the

page_text: inlet passage being more or less opened, gas together with a greater or less propor-
tion of air admitted by the air reservoir valve, is drawn into the charge of air
contained in the cylinder.
When the piston has performed a certain part of its outstroke the gas and air valves
are closed so that as the piston completes its stroke the combustible charge in the
cylinder is expanded below atmospheric pressure.
At the commencement of the following instroke the combustible charge will first
again attain atmospheric pressure and will then be compressed to a greater or less
degree on tlie completion of such stroke.
The accompanying drawing shews the construction of a gas motor engine operating
according to my above described invention.
Fig. 1 is a longitudinal section of the engine, Fig. 2 is a sectional plan, Figs. 3,
4, and 5 shew cross sections, Fig. 6 is a part side view and Fig. 7 is a diagram of the
action.
The space B in the working cylinder in front of the piston A is enclosed by a cover
as shewn, and serves as air compressor, the air being drawn in on the instroke of the
piston and after compression, to a certain extent forced into a reservoir D through
pipe e and inlet and delivery valves ff Fig. 5. The valves and slide of the engine
are worked by means of the way shaft g which makes one revolution for every two
of the crank shaft. The diagram of the pistons motion transferred to the crank path
of the way shaft is shewn at Fig. 7.
From 1 to 2 combustion and development of power takes place in the cylinder.
From 2 to 3 the products of combustion are expelled, from 3 to 4 the charge of
combustible mixture is drawn in and from 4 to 1 it is compressed.
shaft
y
On the expelling stroke before the piston has performed the whole of its stroke, and
is situated at a point corresponding with say the point a Fig. 7, a cam on the way
Fig.
opens the air valve g by means of a lever hand the inlet valve n by
means of the lever p whereupon the compressed air contained in the reservoir D passes
through pipe e and passages and valve n into the space C of the cylinder behind
the piston, where it drives out the residual products of combustion through the
discharge valve ».
When the piston has arrived at the end of instroke, the pressure in the reservoir D
will have sunk to that of the atmosphere, and the discharge valve is closed while
the gas inlet valve is opened. The piston then by its outstroke draws gas in
through pipes, among the air contained in the compression space C and with it any
desired quantity of air, according as the air valve g may be more or less opened or
closed sooner or later. A variable degree of filling is obtained by cutting off the gas
and air supply by closing the valves gi and n at any desired point of the stroke of
the piston, such as for instance the point during the stroke from 3 to 4 Fig. 7.
By the continued motion of the piston the charge in the cylinder is now expanded
to a certain degree below atmospheric pressure so that at the return stroke the
charge is first brought back to aimospheric pressure, and is then compressed in the
compression space.
By this arrangement is attained, firstly, that the charge is freed as much as possible
from combustion products and consists of a comparatively rich gas mixture, containing
the necessary quantity of oxygen for effecting perfect combustion, while, secondly, by
cutting off the gas and air supply at any desired point of the suction stroke any desired
degree of expansion of the combustion gases may be obtained during the working
stroke.
The motor engine can therefore be worked with any desired quantity of combustible
mixture, from the smallest possible charge up to the complete filling of the cylinder
accoring as the inlet valve n, the air valve g, and the gas valve i are closed sooner or
late:.
As shewn on the drawing each engine may be worked with a definitely fixed degree
of expansion, the fixed cams on the way shaft that actuate the valves g and n being so
formed as to effect the closing of the valves at a definite point of the stroke corre-
sponding to the curve 2 to 4 Fig. 7. With this arrangement the gas inlet valve i is

page_text: worked by a sliding cam with incline, controlled by the governor, which either admits
a larger or smaller quantity of gas or cuts off the supply entirely during one or more
working strokes whereby the speed of the engine is regulated.
Instead of an inclined cam a straight cam may be used the regulation being effected
by causing the governor to move the cam to one side so as not to open the gas valve
when the maximum speed is exceeded.
The regulation of the engine may however also be effected by varying both the
degree of expansion and the supply of gas, the time of closing the valves gn and i
being varied simultaneously, for which purpose the cams that open the same are formed
with steps, or with an incline, and are shifted by the governor.
In the arrangement shewn at Fig. 3 the requisite air for forming the explosive
charge is drawn in through the reservoir B, but it can also be drawn directly from the
atmosphere through a branch pipe & Fig. 4, the air valve g being in that case closed
during the suction stroke. The valve o opens automatically during the suction stroke,
so as to admit the required proportion of air and gas to pass into the cylinder through
the inlet valve.
The expansion of the cylinder charge is in this case regulated by closing the gas
valve i and inlet valve n at the corresponding point of the pistons stroke.
This degree of expansion may be a fixed one by working the valves
and n by
means of fixed cams of a determined length. The regulation of the engine is in this
case effected by causing the governor to act upon the gas inlet valve in the before
described manner, but it may also be effected, as before described by varying both the
degree of expansion and the time of closing the gas valve. The ignition of the charge
can be effected in any known manner.
Instead of combustible gas, combustible vapour or spray may be employed, and the
engine may either be vertical, horizontal, or inclined and may have either one or
several cylinders.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed, I declare that what I claim is
--
1. A gas motor engine working with a compression space and with a cycle of four
strokes, wherein the residual products of combustion remaining in the cylinder are
first expelled by a charge of atmospheric air after which a variable charge of com-
bustible gas with or without admixture of air is admitted to mix with the said charge
of air, which supply is capable of being cut off at a variable point of the suction stroke,
so that the combustible charge will be expanded below atmospheric pressure during
the completion of that stroke and is compressed during the return stroke, substantially
as and for the purposes herein described.
2. In a gas motor engine operating as set forth in the preceding claim, the com-
bination with the cylinder of a closed air compressing space B which forces air into a
reservoir D whence it is admitted through pipe e and valves g and n into the rear end
of the cylinder, partly for expelling the residual products of combustion and partly for
forming together with the combustible gas the combustible charge which is rendered
variable by closing the valves for the gas and air supply at a variable point of the
suction stroke, substantially as described with reference to Figs. 1 2 3 5 and 6 of the
drawings.
3. In a gas motor engine constructed and operating as set forth in the preceding
claim, the modified arrangement herein described with reference to Fig. 4, whereby
the air for the combustible charge is admitted through a branch pipe t with automatic
valve, together with the combustible gas, instead of through the reservoir B.
0 1 1
35
1000
ABEL & IMRAY,
Agents for the Applicant.