IMPROVEMENTS IN VALVES FOR APPARATUS WORKED BY STEAM OR OTHER FLUID
Year: 1864

page_text: LETTERS PATENT to Graham Stevenson, of Airdrie, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS
IN VALVES FOR APPARATUS WORKED BY STEAM OR OTHER FLUID."
Sealed the 17th January 1865, and dated the 23rd July 1864.
PROVISIONAL SPECIFICATION left by the said Graham Stevenson at the
Office of the Commissioners of Patents, with his Petition, on the
23rd July 1864.
I, GRAHAM STEVENSON, of Airdrie, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN VALVES FOR APPARATUS WORKED BY STEAM OR OTHER FLUID,"
to be as follows, that is to say:-
This Invention relates to various modifications of valves suitable for various
apparatus worked by steam or other fluid.
One of the simplest modifications is suitable for a steam hammer having a
moving cylinder and a tubular piston rod, by which tubular rod the steam
enters and leaves the cylinder. The top of the rod communicates with the
exhaust pipe, and when applying the improved valve a diaphragm. is formed
across the inside of the rod a little below its top, whilst two sets of openings
are formed in the side, one set below and the other set above the diaphragm.
The valve is cylindrical in form and encircles the rod at the part with the
openings fitting the rod closely at its top and bottom edges, but having its

page_text: middle part hollowed internally. These parts are enclosed in a space forming
the steam chest, into which the steam is admitted in the usual way, and when
the cylindrical valve is lifted so as to uncover the lower openings, the steam
enters by them into the rod and thence into the cylinder, but when the valve
is lowered its hollow part puts the two sets of openings in communication,
and the steam passes into the upper part, and thence away by the exhaust
pipe. The steam pressure being on all sides of the valve it is always in
equilibrio, and it works with the least friction. The valve is by preference
cut through at one side, where it is formed with flanges which are united by
screw bolts, so that by drawing the flanges together, more or less, its fit upon
the rod may be adjusted with the greatest nicety.
The valve may be worked in various ways. In one simple arrangement a
pair of rods are attached, one to each side of the valve, and pass out through
stuffing boxes to a cross head or to levers on a rocking shaft actuated in the
usual way. If the hammer is double-acting the valve will answer with a
suitable disposition of the parts or openings in the rod, the rod being of course
formed with two passages leading one to each side of the piston.
Other modifications of the valve embody the same principal features as that
herein-before described, the valve in each case encircling or encompassing the.
piece formed with openings or ports to be controlled by the valve.
In an arrangement for a steam engine cylinder two of the valves are used,
nd work on two pipes which are fitted in the same line at each end of a.
central exhaust chamber, their outer and opposite ends communicating with
the ends of the cylinder. The two valves are worked by the same rods.
The valve may be in two pieces instead of being open at one side only, and
instead of being cylindrical or of a circular section it may be elliptical, oval,
polygonal, rectangular, or of other convenient form 'in section. The valve
may be made to act by being turned instead of moving longitudinally, in
which case it is made with indentations or openings which uncover the inlet
ports to the steam when the valve is turned into the proper position.
It is an improvement to apply the valve directly to the tubular piston rod
of a steam hammer of the kind herein-before referred to, as the waste of
steam in passages is thereby reduced, and this advantage may be gained by
an ordinary slide valve or other valve different from those herein-before
described, such valve working over ports on one or more sides of the
Inbular rod.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Graham Stevenson in the Great Seal Patent Office on the
21st January 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GRAHAM
STEVENSON, of Airdrie, in the County of Lanark, North Britain, Engineer,.
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of July, in the year of our Lord One
thousand eight hundred and sixty-four, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the said
Graham Stevenson, Her special licence that I, the said Graham Stevenson,
my executors, administrators, and assigns, or such others as I, the said
Graham Stevenson, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
VALVES FOR APPARATUS WORKED BY STEAM OR OTHER FLUID," upon the condition
(amongst others) that I, the said Graham Stevenson, my executors or
administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Graham Stevenson, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement in writing, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say :-
My said Invention relates to various modifications of valves suitable for
various apparatus worked by steam or other fluid, and I have hereunto
appended a Sheet of explanatory Drawings, to be herein-after referred to, and
representing such modifications of my improved valves as will make their
distinguishing features easily understood and to serve as guides in applying
them in the various cases that may arise. In the various Figures of the
Drawings the same or like parts are marked by the same reference numerals
wherever they occur.

page_text: One of the simplest modifications of my improved valves is suitable for a
steam hammer with a moving cylinder and a tubular piston rod such as is
partially represented in vertical section in Figure 1 of the accompanying
Drawings. It is by the tubular rod 1 that the steam enters and leaves
the cylinder (the latter not being shown in the Figure). The top of the
rod 1 is connected to the entablature 2 with the usual annular bearing
surfaces, forming a universal joint, which is easy for any slight vibration or
jarring of the rod. The lower annular bearing surface is in the bottom of the
steam case 3 formed in the entablature 2, and the upper bearing surface is in
the cover 4, which cover is formed with a short branch 5 for the attachment
of the exhaust pipe 6. An opening 7 is formed in the top of the rod 1, and
communicates with the exhaust 6 through the centre of the upper annular
bearing surface. A diaphragm 8 is formed across the inside of the tubular
rod 1 near the top, and two sets of openings or ports are formed through the
sides, one set below and the other set above the diaphragm 8. In the
example represented a malleable iron rod 9, which serves to fix or suspend
the piston more firmly, is held in the diaphragm 8 by its tapered end. My
improved valve 10 is cylindrical, and is shown in cross section in Figure 2; it
encircles the rod 1.at the part within the steam case 3, and between the
spherical bearing surfaces. where the ports are formed through the sides of the
rod. The valve fits closely at its top and bottom, but its middle part is
hollowed internally so that a longitudinal or radial section resembles the
longitudinal section of a common slide valve. When the valve 10 is lifted so
as to uncover the lower ports into the tubular rod, it covers the upper ports,
and the steam enters by the lower ports into the rod and thence into the
cylinder, but when the valve 10 is lowered into the position in which it is repre-
sented in Figure 1, its hollow part puts the two sets of ports in communication
and the steam passes from the cylinder up the rod through the ports to the
space above the diaphragm 8, and thence away by the exhaust pipe 6. The
steam pressure being on all sides of the valve it is always in equilibrio, and it
works with the least friction. The valve is by preference cut through at one
side, as best seen in Figure 2, and at that part it is formed with flanges 11,
which are united by screw bolts, so that by drawing the flanges together more
or less its fit on the rod may be adjusted with the greatest nicety. To prevent
the passage of steam at the joint the valve is there made to fit the pipe from
top to bottom without the middle hollow, which extends round the rest of the
valve, whilst at the corresponding.part of the rod no ports are formed..
The cylindrical valve may be worked in various ways. In the simple arrange-
ment shown in Figure 1, a pair of rods 12 are attached, one to each side of

page_text: the valve 10, and pass out through stuffing boxes in the cover to levers 13,
on a rocking shaft 14, actuated in the usual way. If the hammer is double-
acting the same valve will answer with a suitable disposition of the ports or
openings in the rod 1, such, for example, as is shown in vertical section in
Figure 3 and in cross section in Figure 4. The rod 1 is formed with two
passages leading, one, 15, to the top of the piston, and the other, 16, to the
bottom of it. When the valve is worked by hand it can be made to give
steam below the piston or not at pleasure by moving it more or less down.
The valve is shown in the position for the steam to escape from the upper side
of the piston without entering to the other side. To make the hammer work
automatically with either single or double action, the pulley on the reversing
bar acted on by the "race" on the moving cylinder is mounted in eccentric
bushes which can be adjusted by a handle or lever so that the valve may be
shifted more or less accordingly as the hammer is worked with single or
double action.
Other modifications of my improved valve embody the same principal
features as that herein-before described, the valve in each case encircling or
encompassing the piece formed with openings or ports to be controlled by the
valve.
An arrangement for a steam-engine cylinder is represented in Figures 5, 6,
7, and 8; Figure 5 being a longitudinal section; Figure 6, a plan, with the
valve chest cover removed; Figure 7, an end elevation; and Figure 8, a
cross section.
In this arrangement two of the cylindrical valves 10 are used, and they
work on two pipes 18 which are fitted in the same line at each end of a central
exhaust chamber 19, their outer and opposite ends communicating with the
ends of the cylinder 20. The pipes 18 are made separately, and are entered
into their places and through the valves through openings, in the end of the
casing afterwards closed by covers. They are formed (like the tubular
hammer rod 1) with diaphragms 8, having ports on each side, and the two
valves are worked by the same pair of rods 12.
My improved valve may be in two pieces instead of being, open at one side
only, and instead of being cylindrical or of a circular section it may be
elliptical, oval, polygonal, rectangular, or of other convenient form in
section, but the cylindrical form is obviously preferable. The valve may be
made.to act by being turned instead of moving longitudinally, in which case
it is made with indentations or openings which uncover the inlet ports to the
steam when the valve is turned into the proper position.

page_text: This arrangement will be understood from Figures 9 and 10, which are a
sectional elevation and a transverse section.
In this arrangement the valve 10¹ is shifted by a rocking shaft 21, a lever
on that shaft being connected to it by a link 22, whilst the shaft enters the
steam case by a stuffing box,
It is an improvement to apply the valve directly to the tubular piston rod
of a steam hammer of the kind herein-before referred to, as the waste of
steam in passages is thereby reduced, and this advantage may be. gained by
applying ordinary slide valve or other valve different from those herein-
before described, so as to work over ports on one or more sides of the
tubular rod.
Having thus particularly described my said Invention, and in what manner
the same is to be performed, I have to state that I do not restrict myself
to the precise details herein described or delineated; but that what I claim
as the Invention secured to me by the herein-before in part recited Letters
Patent is,
1, the constructing of valves for apparatus worked by steam or other fluid,
substantially in the improved modes as herein-before described.
And, 2, the applying of a valve directly to the tubular piston rod of a
moving cylinder steam hammer, substantially as herein-before described.
In witness whereof, I, the said Graham Stevenson, have hereunto set
my hand and seal, this Nineteenth day of January, in the year of our
Lord One thousand eight hundred and sixty-five.
Witness,
EDMUND HUNT,
Patent Agent,
28, St. Enoch Square,
Glasgow.
GRAHAM STEVENSON. (L.S.)