Year: 1899

page_text: Date of Application, 23rd Mar., 1899-Accepted, 6th May, 1899
A communication from abroad by the POPE MANUFACTURING COMPANY (INCOR-
PORATED), of Hartford, Connecticut, United States of America.
"
I, PHILIP MIDDLETON JUSTICE, of 55 and 50, Chancery Lane, in the County of
Middlesex, Fellow of the Chartered Institute of Patent Agents, 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 the general class of explosion engines, in which an
explosive mixture, generally carbureted air, is ignited and the expansive force
of the ignited mixture is exerted against a piston. The invention is more espe
cially concerned with engines of this type which have a so-called "free-flying
piston, that is to say, a piston which is not connected directly to a crank, but
flies outwardly against the yielding pressure of a spring, in which energy is thus
stored up, the energy being converted into work during the return movement of
the piston through suitable connections between the returning piston and the
driving shaft or other working part of the engine. The object of the invention
is to secure greater economy of operation, by increasing the rate at which the
heat energy of the explosion is transformed into available work. It has been
proposed, before the date of this invention, to construct explosion engines with
free-flying pistons, but such engines have not, before this invention, become
available for practical use because they have been so constructed as to permit a
large proportion of the energy of the explosion to be wasted in the form of heat
without being converted or transformed into available work, and therefore have
not been economical. It has also been common to compress the charge before
ignition in crank-connected explosion engines, but in such engines a large pro-
portion of the energy of each explosion is wasted in the form of heat. In this
invention a much greater economy of operation is secured than is possible in
either of the forms of engines just referred to, by introducing the compressed
explosive mixture, preferably in a cool condition, into the working cylinder
behind the free-flying piston, and there exploding it. The free-flying piston
being ready to move at the initial increase of pressure within the cylinder, there
is none of that retardation or delay. which, as in the case of a crank connected
piston, or in the case of an engine having a separate explosion chamber, occasions
the communication of some of the available heat to the surrounding walls, but
the maximum rate of conversion of the heat energy into available work is
secured, while the area of the surrounding walls for each, unit of explosive
mixture is the minimum. It will be obvious that the improvement may be
embodied in different forms and constructions, but for purposes of illustration
one suitable form is shown in the accompanying drawing and described herein.
In said drawing,--
Figure is a plan view, partly in horizontal section, of an engine which
embodies the invention, parts of the connecting rod and frame being broken out
to savo snaco ·

page_text: Figure 2 is a side elevation illustrating more clearly the connection between
the piston rod and the driving shaft;
Figures 3 and 4 are detail views of the inlet valve.
In the engine shown in the drawing the cylinder A, piston B, and piston rod C
are shown as of the ordinary form of such parts in explosion engines. A jacket D
surrounds the cylinder, forming an air tight chamber which is in communication
with the forward, open end of the cylinder A, the air in said chamber being com-
pressed by the forward movement of the piston and thereby acting as a spring
or elastic cushion to resist the forward movement of the piston and acting upon
the piston during its return or backward movement to restore to it the energy
which was stored up in the spring or cushion during the forward movement of
the piston. A stuffing box E is provided in the forward end of the jacket to sur-
round the piston rod and permit its movement while permitting the escape
of air.
The main or driving shaft of the engine, represented at F. is provided with a
flr-wheel G and with a suitable drum H. An arm I is pivoted on the shaft F
and is connected by a rod J with the piston rod C. The arm I carries a clutch
or clutch dog K which is adapted to slide freely over the surface of the drum H
during the forward movement of the piston, but to engage said drum during the
return movement of the piston, whereby the piston performs no work during its
forward movement under the influence of the explosion, except to store up
energy in the spring or elastic cushion above referred to, but does perform work
in turning the shaft F during its return movement under the influence of the
spring or piston.
The compressed explosive mixture is stored in a reservoir L which may be
surrounded by a water jacket M to cool the explosive mixture, and such mixture
is admitted directly into the cylinder A. behind the piston B, through a pipe Q
and a suitable valve which is indicated at S and may be operated by a projecting
finger from the piston B to open and admit the explosive mixture into the cylinder
when the piston is at or near the rear end of the stroke, and to close after the
charge of explosive mixture has been so admitted to the cylinder. A pump is
indicated at N for compressing the explosive mixture into the reservoir L, and
it is important to note that the explosive mixture is introduced into the working
evlinder A in a compressed condition, and preferably also in a cooled condition.
The pump may be operated by a crank P on the driving shaft F. The exhaust
port of the cylinder A is indicated at R. the same being controlled so as to open
the exhaust when the piston is at the forward end of its stroke, by a valve and
valve rod T. An ordinary igniting device is represented at V for the purpose of
causing the explosion of the compressed explosive mixture within the cylinder A
and in rear of the piston B.
The mode of operation of the improved engine will be clearly understood from
the foregoing description without further explanation herein.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed as communicated
to me by my foreign correspondent, I declare that what I claim is:-
An explosion engine having a spring or cushion to resist the motion of the
piston in one direction and acting to return it to normal position, with means
for connecting the piston to work during its return stroke under the influence
of the spring or cushion, said engine having also means for compressing the
explosive mixture and introducing the compressed explosive mixture into the
cylinder, and igniting the same within the cylinder and behind the piston, sub-
stantially as described.
Dated the 23rd dow of Wauch 1000