IMPROVEMENTS IN VALVES FOR GAS ENGINES
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
:
I, ROBERT POLLOCK, of 42 New Street, Paisley, in the County of Renfrew,
Engineer, do hereby declare the nature of my said Invention for "IMPROVEMENTS
IN VALVES FOR GAS ENGINES," to be as follows:-
This Invention relates to gas engines and consists in adapting to the cylinders.
of such engines, an improved construction of rotating valve for controlling the
admission of gas and air, the ignition of the explosive charge, and the exhaust
of the products resulting from the combustion of the gas within the cylinder.
The improved valve is of cylindrical form, and is fitted to rotate within a sent
or casing at the end of the cylinder, the casing being provided with inlets for the
gas and air, and an outlet for the exhaust, the inlet and outlet being in com-
munication with the cylinder through separate ports in its end. The valve is
hollowed out at the inlet and outlet ends, which are divided by a transverse web
or partition, and the recess formed in the valve at the inlet side extend's round
one portion of the circumference, while that formed at the outlet end is at á
different part of the circumference, these openings being so formed that while
the valve is at a part of its rotation that the inlet communicates with the
interior of the cylinder, the outlet opening is closed, but coming round towards
the exhaust port in the cylinder. The inlet side of the valve is open to the
cylinder and to the gas and air inlets during the early portion of the outstroke
of the piston, but the rotation of the valve closes off the communication
through it between the gas and air inlets and the cylinder, as the piston
travels out. A small ignition port in the valve then comes opposite a gas jet
playing through an opening in the valve casing, and the combustible charge
within the valve and cylinder is exploded, the expansion which follows driving
out the piston to the full extent of the stroke. During the return of the piston
at the instroke, the valve is in a position at which the exhaust outlet is open,
the opening being so arranged that the exhaust may continue until the comple-
tion of the instroke, the exhaust opening being closed about the same time as
the adinission port opens. The valve is rotated by means of gearing from the
crank shaft so that it may complete a revolution for each revolution of the crank
shaft.

page_text: I, ROBERT POLLOCK, of 42 New Street, Paisley, in the county of Renfrew
Engineer, do hereby declare the nature of my said Invention for "IMPROVEMENTS
IN VALVES FOR GAS ENGINES" and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
•
This Invention relates to Gas engines and consists in adapting to the cylinders
of such engines an improved construction of rotating valve for controlling the
admission of gas and air, the ignition of the explosive charge, and the exhaust of
the products resulting from the combustion of the gas within the cylinder.
The Invention is illustrated in the accompanying Drawings in which Figure 1
is an elevation of a gas engine fitted with the improved valve and Figure 2 is a
horizontal section of the same, Figure 3 is a transverse section of the improved
valve arrangement, through the gas and air admission ports, Figure 4 is a longi-
tudinal section of the same, Figure 5 is a transverse section of the valve through
the exhaust ports. Figures 6 and 7, a section and elevation of the ignition port.
The improved valve A is of cylindrical or conical form and is fitted to rotate
within a seat or casing B at the end of the cylinder C the casing being provided
with inlets & and e for the gas and air and an outlet ƒ for the exhaust, the inlet
and outlet being in communication with the cylinder through separate ports g an h
in its end.
The valve A is hollowed out at the inlet and outlet ends, which are separated
by a transverse web or partition A¹ and the recess a formed in the valve at the
inlet side extends round one portion of the circumference, while that a¹ formed at
the outlet end is at a different part of the circumference, these openings being
so formed that while the valve A is at a part of its rotation that the inlet a com-
municates with the interior of the cylinder as particularly shown in Figures 2 and 3
the outlet opening a³ is closed, but is coming round towards the exhaust port h in
the cylinder, The inlet side a of the valve A is open to the Cylinder and to the
gas and air inlets de during the early portion of the outstroke of the piston but
the rotation of the valve closes off the communication through it between the gas
and air inlets and the cylinder as the piston travels out, A small ignition port i
in the end of the valve A then comes opposite a gas jet ; burning opposite an
opening k in the valve casing B, and the combustible charge within the valve and
cylinder, is exploded, the expansion which follows driving out the piston L to the
full extent of the stroke. During the return of the piston at the instroke the
valve is in a position at which the exhaust outlet a¹ is open, the opening being so
arranged and extending to such a length that the exhaust may continue until
the completion of the instroke, the exhaust opening being closed about the same
time as the admission port opens. The valve A is rotated by means of gearing MN,
from the crank shaft O, so that it may complete a revolution for each revolution of
the crank shaft.
.
The position of the valve A as shown in the drawings is at the point where the
admission of gas and air is just cut off while the ignition port is open for the firing
of the charge and the exhaust valve is about to open.
The valve A is retained in the casing B by a catch P. which is capable of
adjustment to tighten up the valve as it becomes loose by wear.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
The improved rotating valve for gas engines, having formed in it the admission
and exhaust passages communicating with inlet, ignition and exhaust ports in the
valve casing and with corresponding ports in the cylinder, the whole being
arranged to operate substantially as herein described and illustrated.
Dated this Ninth day of December 1884.