Improvements in Gas Engines.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Gas Engines.
I, EDWIN WILLIAM EVANS, of 926 Vine Street, City and County of Philadelphia,
State of Pennsylvania, United States of America, Engineer, do hereby declare
the nature of my invention for IMPROVEMENTS IN GAS ENGINES, 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 engines known as "gas-engines," for
power purposes and has special reference to a construction and operation of a
rotary valve and a valve-jacket for the same that combine the principles of
mixing, ignition, and exhausting, and has for its object cheapness and durability
in construction and operation, avoiding the use of eccentrics and cams, efficiency in
timing the engine; and to the end sought it consists of the novel features of
construction, &c., hereinafter described, and pointed out in the claims.
In the drawings which illustrate my invention,
Figure 1 is a view, partly in vertical section of a rotary valve and its connected
piston, piston-cylinder, &c., embracing my invention.
Fig. 2 is a view in side elevation of the valve-jacket.
Fig. 3 is a cross-sectional elevational view of the same, taken on the line xx,
Fig. 2, and looking in the direction indicated by the arrows 1 1.
Fig. 4 is a similar view looking in the direction indicated by the arrows 2 2.
Fig. 5 is a top sectional view of the jacket, taken on the lines y x, Fig. 2.
Fig. 6 is a sectional view through the horizontal centre of the valve-jacket with
the valve removed.
Fig. 7 is a similar view with the valve in place.
Fig. 8 is a perspective view of the rotary valve.
Figs. 9 and 10 represent vertical sectional views of the same, taken on the
line xxx, Fig. 8, and looking in opposite directions.
Fig. 11 is a horizontal sectional view of the valve, taken on the line z z, Fig. 8,
through its exhaust port; and
Fig. 12 is a similar view taken on the line y z, Fig. 8, through its mixing or inlet
port.
Referring to the drawings, in which the parts are indicated by numerals, similar
numerals wherever used denoting like parts, 1 is the piston-chamber, and 2 the
piston; 3, the power-transmitting wheel; 4, the horizontal shaft to which the
piston is geared; 5, means shown for supporting the shaft and 6 a gear wheel on
the extremity of said shaft. This gear wheel 6 meshes with a larger gear 7,
mounted on the upper extremity of a vertical shaft 8, which is suitably attached to
the valve or plug 9, and the latter rotated by the working of the piston and the
intermediate gearing, for purposes presently more fully explained.
The chamber is in open communication with the jacket 10 of the valve by
means of the port 11. This jacket is preferably constructed to the partial cone or
tapered shape shown in the several figures, formed at one side, preferably integral
therewith, with an inclined vertically-extending chamber or receiver 12, which is

page_text: closed at top and bottom and has a port 11 leading therefrom and adapted to
communicate with the port 11 of the piston cylinder chamber 1, for a purpose
hereinafter made clear. The jacket 10 is provided with a bottom 13, preferably
removable therefrom, and shown retained thereon by means of a screw 14, passing
through the same and engaging a screw-tapped hole 15 in the bottom of the rotary
valve 9 and rotates therewith.
The wall of the jacket 10 about midway its height is bellied or swelled as at 16,
to form the annular chamber or port 17. This chamber or port 17 is in open
communication with the chamber or receiver 12, and the wall thereof opposite said
receiver is formed with inwardly-extending flanges or seats 18 18, the extremities
whereof are flush with the inner side wall of the main body portion of the jacket,
and when the valve 9 is in place within the jacket they engage the same and form
seats for the chamber or port 17, for a purpose more fully explained. The jacket
is further provided with lower and upper ports 19 and 20, which communicate
with the receiver 12 and also with main inlet and outlet ports 21 and 22 on opposite
sides thereof.
Within the chamber 23 of the jacket 10 snugly fits and rotates the plug or
valve 9. This valve is preferably a solid cone-shaped plug of metal cored with the
ports or passage-ways 24 and 25, respectively, near the bottom and top thereof,
which take the oppositely-curved directions shown-that is to say, one extremity of
each port is a vertical line with respect to each other-and they reversely diverge
therefrom in an arc of a circle, so that their respective other extremities are on
opposite sides of the valve or plug. A tapered ignition-chamber 26 is cored through
the longitudinal centre of the valve, its restricted opening being in central alignment
with the ports 24 25 Fig. 9.
I have shown the bottom of the valve or plug screw-tapped as at 15, to receive
the screw 14, for a purpose hereinbefore recited, and provided at its top with a
neck or extension 27, having holes 29 and a pin 29, by means of which connection
is effected with the shaft 8; but other means of connecting the parts may equally
well be employed.
Having now fully described the several parts of my invention, the operation is as
follows:
The cylinder 1 and jacket 10 being connected, so that the port 11 of the
former and port 11 of the jacket form a single port or open communication
between said cylinder and the reciver of the jacket, the gears 6 and 7 meshing
the piston 2 at low centre and the valve 9 in its jacket-so that the port 24
is alone open and is open to the ports 21 and 19 at its respective extremities
and connection made between the port 21 and a source of gas-supply, the wheel 3
is given a turn by hand, when the piston 2 will at once commence to rise and
the valve 9 to rotate, (the gearing being such as to cause the valve 9 to make
a quarter-turn to each stroke of the piston,) and the port 24 gradually closes to
the ports 21 and 19, simultaneously taking in a charge of gas, which flows through
the ports 21, 24, and 19 in turn to the receiver 12, and thence through the
port 11 11 to the piston-cylinder chamber 1, and so continues until the piston has.
reached its top centre-that is to say, made a full stroke-at which time the
port 24 will be entirely closed to the ports 21 and 19 and the valve completed_its.
first quarter-turn, such being the position of parts represented in Fig. 1. The
piston now travels toward low-centre, compressing the confined gas and forcing a
portion through the restricted opening. of the ignition-chamber 26, which is aligned
with the recess 17 of the jacket 10, and the other extremity. of which is now passing.
the flame 30, preferably a Bunsen burner stationed between the seats 18 18, where
the gas is ignited and burns until the piston has completed its downward or second
stroke and reached low centre, at which time the valve will have completed its
second quarter-turn. (See Fig..7.) At this. instant, the lighted gas at the larger
end of the ignition chamber 26 encounters the larger body of compressed. gas.now
contained in the recess 17, receiver 12, port 11* 11; and the lowermost portion of
the piston chamber 1 and explodes the same, causing the piston to rapidly ascend

page_text: to top centre, thus giving momentum and increased power to the driving-wheel 3
through its intermediate gearing, and from there transmitted in a manner well
understood. At this time the piston will have made its third stroke and the
valve completed its third quarter-turn. The port 25 of the valve is now in turn
open at its respective extremities to the ports 20 and 22 and completely exhausts
the exploded gas as the piston travels toward low centre again to make its fourth
stroke, at the completion of which the valve will have made its last quarter-turn
and the port 25 will be closed and the parts in position to take in a new charge
of gas and repeat the operation of mixing, compressing, exploding, and exhausting
charges of gas or the like.
Having now described my invention, I wish it understood that I do not desire to
limit myself to the exact construction of parts shown in my drawings and described,
but may vary the same in any manner to better carry out the principle of my
invention without departing from the true scope thereof.
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 what I
claim is:
1. In a gas engine, the combination, with the piston-cylinder, piston, and its
connected power-transmitting gearing, of the jacket inclosing the valve, having
supply and exhaust ports, and a receiving-chamber provided with a port con-
nection with the piston-chamber and port connections with the valve-chamber,
and a valve of the character herein described within said jacket, geared to the
piston and adapted to rotate, as described, and for the purposes set forth.
2. In a gas-engine having a source of gas-supply, a rotary valve of the character
herein described, having mixing, igniting, and exhaust ports, in combination with a
jacket having a supply-port, adapted to communicate with the mixing-port in the
valve at pre-determined intervals and an exhaust-port adapted to communicate
with the exhaust-port in the valve at predetermined intervals, a receiving-chamber
in open communication with the piston-chamber and having port connections with
the valve-chamber adapted to communicate with the mixing and exhaust ports of
the valve at predetermined intervals, an annular recess-port in the body of the
jacket about the valve in open communication with the receiving-chamber and
provided with seats engaging the valve, the igniting-port in the valve working in
alignment with said annular recess-port, and means at or between said seats
whereby the gas in said ignition-port may be ignited to in turn ignite or explode
the main body of gas in the manner described, whereby a charge of gas may be
taken into the piston-chamber, &c., and in turn compressed, ignited, exploded,
and exhausted, thereby imparting momentum to the piston and its power-trans-
mitting gearing, as and for the purposes set forth.
3. In a gas engine, a rotary valve of the character herein described, consisting
of a plug of metal or the like having reversely-diverging ports, as and for the
purposes set forth.
4. In a gas engine, a rotary valve of the character herein described, consisting
of a plug of metal or the like having upper and lower reversely-diverging ports
and a central horizontal port, as and for the purposes set forth.
5. In a gas engine, in combination with a suitable jacket having communication
with the piston-chamber and provided with supply and exhaust ports, a rotary
valve of the character herein described within said jacket and consisting of a plug
of metal or the like having upper and lower reversely-diverging ports and a central
horizontal port, as and for the purposes set forth.
1001
Dated tuny
EDWIN WILLIAM EVANS.
Hughes, Eli & Hughes,
76, Chancery Lane, Lendon, W.C., Agents for the Applicant.