AN IMPROVED VALVE FOR CONTROLLING THE STEAM SUPPLIED TO STEAM CYLINDERS
Year: 1884

page_text: I WILLIAM THORLEY STEWART of Glanmire in the County of Cork Ireland Mill
Owner and Merchant, do hereby declare the nature of my invention for AN
IMPROVED VALVE FOR CONTROLLING THE STEAM SUPPLIED TO STEAM
CYLINDERS to be as follows:-
'
ENGINE
The object of the invention is to provide an improved valve for effecting the
better control of the admission, distribution, exhaust and cut off of the steam as
supplied to the cylinders of steam engines in order to economise the steam employed
and to facilitate those operations. In carrying out my invention I construct the
valve of cylindrical form fitted to revolve or move or oscillate as well as traverse
end wise within another cylinder which forms in fact the seat.
The improved valve is composed of an outer cylinder formed to receive an inner
cylinder or tube or it may be sections of a tube, and this inner cylinder is formed
so as accurately to fit the outer cylinder for portions of its length and this inner
cylinder may be provided with packing rings, or V grooves to be able to move
steam-tight in the outer cylinder while having a rotary or oscillatory, and also a
longitudinal movement or this fitting may be otherwise insured.
B
This outer cylinder has two or more ports at or near each of its ends, which ports
unite into one passage leading to the steam engine cylinder. One of these ports at
each end is of a rhomboidal shape or of other suitable form, the longer sides of
which are arranged obliquely to both across and longitudinal section of the cylinder
and form as it were a spiral port on the inside of the cylinder and winding in &
spiral or twisted direction or form into a rectangular port at right angles to the
longitudinal axis of the cylinder, and this rectangular port communicates with the
end of the steam engine cylinder.
The other two ports, which I will call for distinction (although they are not
necessarily so) the inner ports, are merely rectangular parallelograms.
The casting or part containing the passages whereby the oblique ports are
carried in a curved direction round into a rectangularly formed port, and also the
passages for the other two ports, may be part of the valve cylinder casting or part
of the steam engine cylinder casting, or be a casting separate from both as may be
most convenient.

page_text: On this outer cylinder are bolted, or screwed, end covers, on one or both of which
is provided a stuffing box and gland and also on one or both of these covers is
affixed a steam pipe connection.
The inner tube or tubular part, which works in the outer cylinder is divided into
three sections by two plain bulk-heads at about a fourth of its length from each
end of the tube and the two outer sections or chambers thereby formed may com-
municate with one another by means of a steam pipe or passage passing from one
bulkhead to the other through the centro section. In each of these sections are
ports which operate with those in the cylinder, the two in the end sections for the
admission and cut off of steam to the steam engine cylinder and the two in the
centre section to allow the exhaust steam to pass away through into the interior of
the tube and then away through ports in a belt of the contre of the tube into the
atmosphere or a condenser, or the steam ports may be in the centre section and the
exhaust ports in the end sections. The ports for the admission and cut off of the
steam may be either triangular or rhomboidal or other suitablo shape and those
for the exhaust to take place through may be oblong or otherwise, as most
convenient.
In some cases it may be found more convenient for the centre belt of the tube to
be omitted altogether and for the two ends to be supported and kept in position
at a distance from one another by being bolted to or cast in one with the centre
steam pipe or passage or solid shaft or trunk.
In this modification of my invention the exhaust ports of the outer cylinder when
uncovered by the notch in the tube coming opposite them alternately have direct
communication with the exhaust pipe. A valve rod is attached to one or both of
the bulkheads of the tube and passes through a gland or glands on the outer cylinder
covers and thereby, a rotary, oscillating or reciprocating movement may be com-
municated to the tube from the crank shaft of the steam engine, by gearing or
otherwise, and the steam and exhaust ports are thereby brought alternately opposite
the ports in the outer cylinder and at the same time as the rotary or oscillatory move-
ment is communicated from the crank shaft a longitudinal or transverse movement
may be communicated to the tube from the governor by gearing or otherwise or by
hand gear, whereby the cut off of the steam and the ratio of expansion may be
altered by causing the oblique ports to remain open during a longer or shorter
period during each revolution of the tube or should a reciprocating movement be
communicated to the valve from the crank shaft, then. a rotary or partial rotary
movement may be communicated to it from the governor for regulating the cut off_
of the steam or the cut off may be effected by an ordinary link movement.
When a rotary movement is employed from the crank shaft the exhaust and
steam ports of each end are at opposite sides of the tube but when a reciprocating
movement is used all the ports are in the same line at one side of the tube.
Both ends of the tube being in direct communication with the steam supply
either through the pipe connecting the two bulkheads or where instead of the pipe
a solid shaft or trunk is used for supporting the tubular ends, by a steam
connection on each cover of the outer cylinder the pressure in both ends being
equal and bring in opposite directions the valve works balanced or in equilibrium.
Dated this 4th day of June 1994

page_text: COMPLETE SPECIFICATION.
J
I WILLIAM THORLEY STEWART of Glanmire in the County of Cork Ireland Mill
Owner and Merchant do hereby declare the nature of my invention for AN
IMPROVED VALVE FOR CONTROLLING THE STEAM SUPPLIED TO STEAM ENGINE
CYLINDERS and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
The object of the invention is to provide an improved valve and system of ports
and passages for effecting the better control of the admission distribution, exhaust
and cut off of the steam as supplied to the cylinders of engines in order to economise
the steam, employed and to facilitate these operations. In carrying out my
invention I construct the valve of cylindrical form fitted to revolve, or oscillate, or
have a reciprocating motion, or any two of these movements at the same time,
within another cylinder, which forms in-fact the valve sent.
In the accompanying drawing Figure 1 shows a horizontal section of one form of
arrangement of the valve and parts taken on the line A. A. of Figure 2. Figure 2
is a vertical section of the valve seat or outer cylinder. Figure 3 is a horizontal
section of another form of arrangement of valve and parts. Figure 4 shews the
valve proper separately. Figure 5 shows a modification of this valve proper by
forming it with sections of a cylinder. Figures 69 and 10 show the valve formed
as a semi or other segment of a cylinder and Figures 7 and 8 are sections thereof
respectively on the lines B. B. and C. C.
The improved valve is composed of an outer cylinder a formed to receive an
inuer cylinder b (Figures 1 and 3) or section of a cylinder or tube (Figures 6. 9.
and 10) or it may be the sections of a tube (Figure 5) kept in position at a
distance from one another, by a pipe, or shaft, and this inner cylinder or part of a
cylinder bis formed so as accurately to fit the outer cylinder for portions of its
length and may be provided with packing rings or V grooves or other devices so as
to be able to move steam tight in the outer cylinder a while having a rotary or
oscillatory, or longitudinal reciprocating movement, or this fitting may be otherwise
insured.
The outer cylinder a has two or more ports a¹ a² at or near each of its ends, and
these ports a' a unite into one passago a leading to the engine cylinder d. One
of these ports a' at each end may be of a triangular, rhomboidal, or other suitable
form the longer sides of which are arranged obliquely to both a cross and longi-
tudinal section of the cylinder a and form as it were, a spiral port on the inside of
the cylinder a and winding in a spiral or twisted direction or form into a rectangular
port or passage a³ at right angles to the longitudinal axis of the engine cylinder d
with which cylinder this rectangular port or passage a³ communicates.
These ports a' in the outer cylinder may if so desired, be plain rectangular ports
at right angles to the line of the piston rod the same as the steam passages into the
steam cylinder,

page_text: The other two ports a² which I will call for distinction although they are not
necessarily so, "the inner ports," may be merely rectangular parallelograms, or
other suitable form.
The casting or part a containing the passages a³, whereby the oblique ports a¹
are carried in a curved direction or form, round into a rectangularly formed port,
and also the passages of the other two ports a³ may be part of the casting of the
outer cylinder a of the valve, or part of the engine cylinder casting d or be a
casting separate from both, and mercly jointed to them with bolts and nuts, as may
be found most convenient.
On the outer cylinder a of the valve bare bolted or screwed end covers c, and
on one or both of these covers is provided a stuffing box o' and gland and also on
one or both of the covers is a steam pipe connection c³. The inside tube b or parts
of a tube which work in the outer cylinder, a is divided into three sections or
chambers, 1. 2. 3 by two plain bulk heads e el at about one fourth of its length
from end of the the tube b and the two outer or end sections or chambers 1 and 3
thereby formed may communicate with one another by means of a steam pipe or
passage passing from one bulk head e to the other bulk head e¹ through or across
the centre section 2, or by a groove or passage sunk in either the outer cylinder, or
tube, lengthwise or spirally. In each of these sections 1. 2. and 3 are ports which
operate with those in the valve seat a the two ports 61 63 in the end sections for
the admission and cut off of the steam to the engine cylinder d and the two
ports b³ ³ in the centre section to allow the exhaust steam to pass away through
into the interior of the centre section or chamber 2 of the tube, and then away
through ports b' in a belt in, or about, the centre of the tube b into the atmosphere
or to a condenser by passage a³ or this arrangement may be varied by the steam
ports being in the centre section or chamber 2 and the exhaust ports in the end
sections 1 and 3.
The ports 6162.in the tube or section of a tube b for the admission and cut off of
the steam may be either triangular, rhomboidal, plain parallelograms, or other
suitable shape, and those for the exhaust to take place through, may be oblong or
otherwise as most convenient.
In some cases it may be found more convenient to omit the centre belt of the
tube baltogether and support the two ends 1 and 3 and keep them in position by
bolting the two bulkheads e e¹ to the flanges of the connecting steam pipe for
solid shaft or trunk or by casting the end sections 1 and 3, bulk heads e. e' and
pipe or trunk fall in one. In this modification of my invention the exhaust ports
of the outer cylinder when uncovered by the notches or ports in the tube b coming
opposite them alternately have direct communication with the exhaust pipe a to
the atmosphere or condenser.
A valve rod e is attached to one or both of the bulkheads e e¹ of the tube and
passes through a gland or glands on the outer cylinder covers e and thereby a
rotary, oscillating, or reciprocating movement inay be communicated to the tubo b
from the crank shaft of the engine by gearing or otherwise so that the steam
ports and exhaust ports b³ can be brought alternately opposite the ports a¹ a²
in the outer cylinder. Should a rotary or oscillating movement be used for
covering and uncovering the ports then there may be communicated to the tube b
at the same time a longitudinal or transverse movement through the outer cylinder
to alter its position in the outer cylinder or seat, whereby the cut off of the steam
and the ratio of expansion will be altered by its causing the oblique ports to remain
open during a longer or shorter period of each revolution, or oscillation of the tube.
This longitudinal movement may be communicated to the tube b from the governor
by gearing or otherwise, or by hand gear. Should a reciprocating movement be
used for covering and uncovering the ports alternately then a partial rotary
movement communicated from the governor or by hand gear to the tube b may be
used to turn the tube or valve b partially round on its axis, and by so turning it to
the right or left of its mean position causo the oblique ports to close sooner

page_text: or later, and consequently regulate the point of cut off and ratio of expansion,
or the cut off may be effected and regulated by an ordinary link and two
excentrics.
When a rotary movement is employed for opening and shutting the ports
alternately then the exhaust and steam ports at each end of the tubo are at
opposite sides of it but when a reciprocating movement is used all the ports are in
the same line along the tube. When an oscillatory movement is used, then the
exhaust and steam ports at each end are at opposite sides of a longitudinal strip or
segment of the tube the breadth of which is at least equal to the length of
the ports.
Both ends of the tube b being in direct communication with the steam supply
either through the pipe connecting the two bulkheads e e' (or where a solid shaft
or trunk is used instead of the central pipe ƒ by a steam connection on each end
cover) or by a groove or passage from one end chamber to the other, the pressure in
both ends is equal and being in opposite directions the tube works balanced or in
equilibrium, when so desired, but more pressure may be put on one side of the tubo
than on the other when so desired for the purpose of keeping the valve or tube b
tight to its seat by having a recess or grooves in the opposite side of the cylinder a
to that containing the ports and into which the steam from the ends has free access
or where a reciprocating movement is used for working the valve b this object may
be attained by omitting a longitudinal segment of the tube altogether at the side
opposite to that containing the ports or in other words by using a longitudinal
segment of a tube altogether at the side opposite to that containing the ports or in
other words by using a longitudinal segment of a tube or cylinder for the valve
instead of a complete tube or cylinder as shewn by Figures 6, 7, 8, 9 and 10.
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 combinations or arrangements of parts forming valves having each but one
moving part for controlling the supply of steam to steam cylinders consisting each
of a valve case provided with separate exhaust and inlet ports and passages, either
united into one passage into the engine cylinder or kept separate throughout,
operating with a valve b (the only moving part) of cylindrical form, or allied, or
partly cylindrical form adapted to enable the cut off and ratio of expansion
of steam to be altered to suit variation of load on the engine without altering
the lead or time of opening or closing of the exhaust ports substantially as set
forth
Dated this 3rd day of March 1885.
W
BROOKES & SON,
55 & 56, Chancery Lane, London,
Agents for the said William Thorley Stewart.