An Improvement in Gas Engines.
Year: 1892

page_text: Date of Application, 15th Oct., 1892
Complete Specification Left, 17th July, 1893-Accepted, 14th Oct., 1893
PROVISIONAL SPECIFICATION.
An Improvement in Gas Engines.
I, FREDERIC WILLIAM CASWELL COCK, of Elmstead Lodge Bathwick,
Bath, in the County of Somerset, Inventor do hereby declare the nature of this
invention to be as follows:-
This my invention relates to an improvement in gas or other vapour engines,
and my invention consists in an improved method of controlling the admission of
gas or vapour and air into the cylinder.
My invention has reference to that class of engine in which the crank works
in a closed chamber and in which an impulse is obtained at each revolution such
as is described in the Specification No. 6410 dated April 14th 1891, or an engine
in which the forward stroke of the piston compresses the charge within the
cylinder at the opposite end thereof to that in which the charge is fired such as
described in the Specification No. 9247 dated June 1st 1891.
In the said Specification the air and gas forming the charge are described as
being drawn in to the compression chamber through a valve or valves in the
said chamber, the said valves being opened by an excess of fluid pressure from
the outside.
My improvement consists in dispensing with the valve controlled inlet such
as described which it is found is not certain in its operation and in admitting
the air and gas or a mixture of the same through a port or ports formed
through the cylinder at a suitable position.
The inlet port communicates with the source of supply of the gas and air
which passes into the cylinder through the said port, I may, however, if found
desirable have separate passages into the cylinder for the air and gas respectively,
the flow of the explosive mixture being controlled by a suitable governor.
The said inlet port is preferably so disposed that it is uncovered by the piston
when the latter approaches the limit of its return stroke, the gas and air passing
into the crank chamber or non-ignition end of the cylinder where it is com-
pressed and from which it is conveyed to the firing end of the cylinder through
any suitable channel.
The opening and closing of the inlet port by the piston insures a more uniform
charge being admitted and the volume more positively determined than by the
mechanism described in the before-mentioned Patents.
The air and gas supply may, if desired, be connected to a chest or casing
annexed to or formed integral with the cylinder the said casing having a slide
or other valve arranged therein.
Dated this 15th day of October 1800
HORN & SON,
Applicant's Agents.
COMPLETE SPECIFICATION.
An Improvement in Gas Engines.
I, FREDERIC WILLIAM CASWELL COCK of Elmstead Lodge Bathwick,
Bath, Inventor 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 has reference to that class of gas engines in which the crank
works in a closed chamber, or casing, (the explosive mixture being slightly

page_text: compressed in this chamber) and in which an impulse is obtained at each revolu-
tion, such as is referred to in the Specification of the Patent No. 6410 dated
14th April, 1891, granted to Joseph Day;-or an engine in which the piston
during its forward stroke compresses the charge within the cylinder at the
forward end corresponding to the closed chamber or casing aforesaid, such as is
referred to in the Specification of the Patent No. 9247 dated 1st June 1891,
also granted to Joseph Day.
In the said Specifications the air and gas forming the charge are described as
being drawn into the compression chamber, or casing through an inlet port or
ports furnished with a valve or valves in the said chamber or casing, the said
valve or valves being opened by reason of the external pressure of the air and
gas being superior to that inside.
Now in my improved engine I move the inlet port or ports from the chamber
itself and place it or them in the cylinder and in such a position and make it
or them of such form that it or they shall be covered by the piston throughout
the entire revolution of the crank-shaft except for an extremely brief period,
when the piston is close to the end of its return stroke. By this arrangement
the piston itself forms the covering valve for this inlet port or these inlet ports
and defines the period and duration of the admission thus ensuring that a more
uniform charge shall be admitted and that the volume shall be more positively
determined than was possible by the provisions made for that purpose in the
before-mentioned Specifications.
And in order that this my invention may be more readily understood I have
appended hereto certain illustrative drawings in which
Figure 1, Sheet 1 is a sectional elevation with the piston at the top of its
stroke (assuming the engine to be vertical),
Figure 2 is an end elevation partly in section, with the piston at the bottom
of its stroke, and
Figure 3, Sheet 2 is an end elevation.
In these drawings the admission of gas and air is shewn as through two
separate ports the air being admitted by the port F while the gas is admitted
by the port G. These ports it will be seen are of considerable width but of
little depth so that the duration of their opening will be brief, as they will be
closed except when the piston A. is at or near the extreme of its return stroke.
The flow of the gas { and }}
any suitable device.
air or of the explosive mixture may be controlled by
In the case of a horizontal engine of the kind shown on the drawings and
described in the Specification of the Patent No. 9247 of 1891 aforesaid the gas
and
or
}.
air or the explosive mixture pass or passes into that end of the cylinder
which corresponds to the chamber E of the example shown in the appended
drawings of this, my application.
The following is a description of the mode of working of this engine:
Assuming the piston A to be at the top as shown in Figure 1, it will be seen
that the air and gas ports are uncovered, and are now in free communication
with the chamber E, in which at this time, a partially vacuous condition exists,
and the air and gas rush in to satisfy this vacuous condition. At this moment
also the explosive mixture is in a compressed state above the piston and is
driven into the igniting tube M shown as placed in the top cover of the cylinder B
which ignites it in the usual manner, producing the downward or "power
stroke. Almost immediately after the commencement of this downward stroke
the gas and air ports are closed by the descent of the piston which then begins
to slightly compress the gas and air mixture which has been drawn into the
chamber E below it. By the time that the piston has completed its downward
stroke as shown in Figure 2 it has uncovered the outlet port N, thus allowing
the products of combustion to escape, and it has also uncovered the upper
"

page_text: mouth of the passage Lx forming the communication between the chamber E
and the upper side of the piston. The products of combustion have as regards
the bulk of them, escaped through the exhaust by reason of their pressure
above the external atmosphere, and, so soon as this escape has lowered that
pressure to the condition prevailing in the chamber E the mixture passes up the
passage L into the upper part of the cylinder coming in contact with the shield
or deflector O which is carried on the top of the piston. This shield or deflector
prevents the passage of the mixture across the top of the piston, and so out by
the outlet port and compels it to rise to the top of the cylinder passing away
from the exhaust port thus enabling it to sweep round and chase before it the
small portion of the products of combustion, remaining in the cylinder. By this
time the piston has so far advanced in its upward stroke as to cover the mouth
of the exhaust Q of the passage L*. During the ascent of the piston it will be
seen that the before-mentioned partially vacuous condition in the chamber E below
it is produced. The cylinder is shown water-jacketted in the usual well known
manner.
An erect vertical engine only has been shown in the drawings and the mode of
working has been described in reference thereto but it will be obvious that the
engine may be inverted or may be placed horizontally or at any intermediate
angle.
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 I am
aware that propositions have been put forward for making gas engines wherein
the ports have been opened and closed by the movement of the piston itself
(although I am not aware that any of them have come into commercial use) 1
do not therefore claim the construction of such gas engines generally, but, what
I claim is :-
The construction of gas engines as described with reference to the drawings
wherein the inlet port and its valve are removed from the position in which they
are placed in the types of engines described in Joseph Day's before mentioned
Specifications and where the inlet port or ports is or are so placed in reference to
the piston as to be controlled by the movements of that piston being opened and
closed when the piston is near the extreme of its return stroke, the piston being
furnished as in the engines of the said Day's Specifications, with a shield or deflector
or the alternative provisions mentioned in the Specifications to prevent the incoming
current of mixture from escaping at the exhaust port before ignition all substan-
tially as hereinbefore described with reference to the illustrative drawings Figs. 1,
2 and 3.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.