IMPROVEMENTS IN AND RELATING TO "GAS ENGINES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Edmund Grace Wastfield at the Office
of the Commissioners of Patents on the 6th October 1882,
EDMUND GRACE WASTFIELD; of Liverpool, in the County of Lancaster
"IMPROVEMENTS IN AND RELATING TO "GAS ENGINES"
4
My Invention has for its object certain improvements in and relating to "gas
.engines."
The improvements to which my Invention relate, consist
First in the order of admission of the gas and air composing the combustible
fluid.
"
Second in a certain novel arrangement of combustion chamber and duplex
piston.
Third in a certain system or method which I employ for expelling the.products
of combustion, or waste gases.
Fourth in a certain arrangement of inlet port for the combustible fluid into
the working cylinder and exhaust port therefrom.
Fifth in a certain arrangement of slide, valve and admission port and ignition
port and to a novel system of sustaining the ignition flame and firing the
combustible fluid in the cylinder.
Sixth. In a novel arrangement of gas supply valve and method of governing, or
regulating the gas supply to the working cylinder.
Seventh In a certain arrangement of combustible fluid compression pump,
whereby I can produce in combination with the other parts of my Invention an
engine that will give an effective stroke for every revolution of the crank.
In construction, the principal parts of the gas engine to which my Improvements
relate are materially of ordinary construction, namely, a water jacketted working
cylinder, open at one end and provided with the usual connecting rod, crank shaft
and fly-wheel, all mounted on a suitable frame or bedplate.
Under the first part of my Invention, I admit into the working end of the
cylinder gas and atmospheric air, in the following order, namely I first admit gas
alone, I then admit an inflammable mixture of gas and air, and lastly I admit gas
alone or a richer mixture of gas with air I thus have first a charge of gas, then
gas and air and lastly gas alone or the richer mixture These fluids are (when
D...

page_text: the engine is working separated from the seventh part of my Invention) drawn
into the working cylinder behind the piston hereafter described, by the outstroke
of the piston. They are then compressed by the next instroke and ignited and
exert their expansive force on the following outstroke, and the products of
combustion are expelled by the following instroke. By admitting the combustible
fluid in the order just described I obtain a more sustained pressure behind the
piston.
Under the second and third parts of my Invention, the combustion chamber and
piston is constructed thus: the main piston is of cylindrical construction, provided
with spring packing rings, the connecting rod end is open and the working end is
provided with a loose piston working inside the main piston, and provided with
suitable packing rings.. Between the working and of the piston and the open-end,
there is a diaphragm which forms a chamber at the working end of the piston.
This diaphragm is provided with a suitable valve opening inwards so arranged
that air can pass into the space, or chamber between the diaphragm and the loose
piston, but cannot return past the said valve. The inner, or loose piston is also
provided with a valve of small area, also opening into the chamber in the main
piston. This valve is loaded by.a. spring, or its equivalent and the action is as
follows: on the piston making an outstroke, the air passes through the valve in the
diaphragm and the inner piston is forced to the end of the main piston, where it
abutts against a suitable stop. On the return, or instroke of the main piston all
gases are expelled from the working end of the cylinder. On the next outstroke
the combustible fluid is drawn into the working cylinder and on the next instroke,
the combustible fluid is compressed into the main piston, by the loose piston being
forced by such compression into the main piston, leaving an open space at the end
of the main piston, which space forms the combustion chamber. The loose piston
is forced into the inain piston against an abuttment which forms its limit of travel.
The valve in the loose piston is loaded against the extreme pressure of the
compressed fluid. The compressed charge is then fired, and the expansion of coin-
bustion causes an effective stroke of the main piston. The pressure of combustion
is sufficient to open the valve in the loose piston and allow a certain portion of
the waste gases to pass through the valve in the loose piston, into the chamber
behind such piston. The result is that an expansive force is created in such
chamber, which is sufficient to force the loose piston back into its normal position
in the main piston so that on the instroke of the main piston, all. tho products of
the previous combustion are expelled from the cylinder. Thus the loose piston
forms an elastic cushion within the main piston, which at each exhaust instroko
expels the products of the previous combustion, and at each compression instroke,
is forced into the main piston, so as to form a combustion chamber of the inner end
of the main piston.
Under the fourth part of my Invention, the combustible fluid inlet port is at
the side and back end of the cylinder and opens into the passage leading to the
exhaust, the one opening into the cylinder serving both as inlet and exhaust. In
order to lessen the noise of the exhaust I pass the exhaust into a closed chamber
with a double diaphragm with differentially positioned holes so as to break, or check
the exhaust.
Under the fifth part of my Invention the slido valvo is situated at the side of
the cylinder across the inlet port. My improved slide valve is provided with a
mixing chamber formed inside the slide, such clamber being sufficiently prolonged
and curved at each end to answer the purpose of the port for the admission of the gas
and of the requisite supply of air to form the mixture. The air admission port of
the slide valvo is opened subsequently to and is closed previously to the gas port,
whereby 1 obtain the particular order of admission already referred to under the
first part. 1 use an arrangement to effect the ignition of the charge as follows: on
the side of the slide valve is a short curved port leading from the aperture by
which gas is supplied, to the gas flame that ignites the charge. Such curved port
is sò arranged that sometime previous to the port, or chamber containing the

page_text: igniting flame opening to the main port of the cylinder, a portion of the combustible
mixture is taken from the top of the cylinder port and owing to the order of
admitting the combustible fluid to the cylinder, the portion taken is nearly pure
gas, which burns with a strong flame in the ignition port without firing back into
the cylinder. I preferably use this ignition flame in triplicate by passing the gas
through three holes into the ignition chamber.
Under the sixth part of my Invention the gas supply valve consists of a spring
retained piston valve worked by a lever of the first order and link, one end of
the lever being attached to the slide valve and the other end of the lever attached
to the link which works the supply valve. On the lever there is an adjustable
stop which comes against a variable abuttment worked by the governor. According
to the position of this abuttment the fulcrum of the lever is altered and the supply
of gas regulated.
Under the seventh part of my Invention, I provide a combustible fluid com-
pression pump, in which case I vary the order of admission described under the
first part and I simply force a combustible mixture of gas and air behind the
working piston on each instroke, the enforcement taking place immediately after
the products of the previous combustion have been expelled by the piston of the
second part. By this arrangement an effective stroke of the engine is produced for
every revolution of the crank,