IMPROVEMENTS IN SLIDE VALVES AND ARRANGEMENTS FOR WORKING THE SAME. SLIDE VALVES AND ARRANGEMENTS FOR WORKING THE SAME.
Year: 1872

page_text: LETTERS PATENT to Joshua Rooke, of No. 18, London Street, in the
City of London, Engineer, for the Invention of "IMPROVEMENTS IN
SLIDE VALVES AND ARRANGEMENTS FOR WORKING THE SAME.
SLIDE VALVES AND ARRANGEMENTS FOR WORKING THE SAME.
"
Sealed the 3rd September 1872, and dated the 18th May 1872.
PROVISIONAL SPECIFICATION left by the said Joshua Rooke at the
Office of the Commissioners of Patents, with his Petition, on the
18th May 1872.
I, JOSHUA ROOKE, of No. 18, London Street, in the City of London,
Engineer, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN SLIDE VALVES AND ARRANGEMENTS FOR WORKING THE SAME," to
be as follows:-
My Invention consists in an improved arrangement of compound
slide valve used for the admission into the cylinder, and eduction from
the cylinder, of steam or other expansive fluids, whereby the admission
of steam or other expansive fluids can be regulated and cut off at any
part of the stroke of the piston, and the pressure on the slide faces can
be completely balanced.

page_text: My improved compound valve consists of a main valve containing
cut-off or expansion interior valves, which are so arranged as to be able
to cut off the steam or other expansive fluids at any part of the stroke
of the piston, while at the same time the interior valves and the main
valve are perfectly balanced.
The main valve may be worked by any of the means usually adopted
in land or marine engines. The expansion or cut-off valves are worked
through a lever connected with the piston tail rod and with the valve
rod, or by any other suitable separate action taken either directly from
the piston or its appurtenances, or from the shafting. The amount of
expansion is regulated by adjusting the positions of the cut-off or ex-
pansion interior valves.
A governor may be applied so as to affect directly the amount of
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joshua Rooke in the Great Seal Patent Office on
the 18th November 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSHUA
ROOKE, of No. 18, London Street, in the City of London, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of May, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Joshua Rooke, Her special license that I,
the said Joshua Rooke, my executors, administrators, and assigns, or
such others as I, the said Joshua Rooke, 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 SLIDE VALVES AND ARRANGE-
MENTS FOR WORKING THE SAME," upon the condition (amongst others) that
I, the said Joshua Rooke, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,

page_text: 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 Joshua Rooke, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
My Invention consists in an improved arrangement of compound
slide valve used for the admission into the cylinder, and eduction from
the cylinder, of steam or other expansive fluids, whereby the admission
of steam or other expansive fluids can be regulated and cut off at any
part of the stroke of the piston, and the pressure on the slide faces can
be completely balanced.
My improved compound valve consists of a main valve containing
cut-off or expansion interior valves which are so arranged as to be able
to cut off the steam or other expansive fluids at any part of the stroke
of the piston, while at the same time the interior valves and the main
valve are perfectly balanced.
The main valve may be worked by any of the means usually adopted
in land or marine engines. The expansion or cut-off valves are worked
through a lever connected with the piston tail rod and with the valve
rod, or by any other suitable separate action taken either directly from
the piston or its appurtenances, or from the shafting. The amount of
expansion is regulated by adjusting the positions of the cut-off or ex-
pansion interior valves.
A governor may be applied so as to affect directly the amount of
expansion in the cylinder in cases where such action is desirable.
In the accompanying Drawings Fig. 1 (Sheet 1) is a central vertical
section of parts of an engine shewing my improved compound slide
valve made circular in form; Fig. 2 is a horizontal section taken
partly in the line A, B, of Fig. 1, and partly in the line C, D, of the
same Figure; and Fig. 3 is a sectional plan of the main and expansion
valves.
The main valve a contains the cut-off or expansion interior valves b.

page_text: expansive fluids at any part of the stroke of the piston, the interior
valves 6 and the main valve a being perfectly balanced by the steam
or other expansive fluid being admitted or cut off all round their
working faces simultaneously.
The main valve a is worked by any of the means usually adopted in
land or marine engines. The expansion or cut-off valves 6 are worked
through a lever (indicated by the line c) having its fulcrum at d, and
connected by a link with the piston tail rod e, and by another link with
the valve rod f. The arrangement for altering the amount of expansion
is shewn in Fig. 1, where 9 and h are left and right handed screws 1
working in nuts i and k. When the rod is turned to the right by the
mitre wheels the valves 6 will be moved further apart, which will
cause the steam or other expansive fluid to be cut off at an earlier
part of the stroke, and when the rod is turned to the left these valves
will approach each other and cut off the steam or other expansive fluid i
at a later part of the stroke. The valves 6 are prevented from turning
by the rod o.
The gear
7 for altering the expansion or cut-off valves is so arranged
as to be used when the engine is in motion, and. I am thereby enabled
to apply a governor to the shaft m to affect directly the amount of ex-
pansion in the cylinder in cases where such action is desirable.
The arrows colored black represent the passage of the steam or other
expansive fluids from the boiler or other reservoir, while those colored
red shew its eduction from the cylinder into the condenser, receiver, or
regenerator.
Fig. 4 (Sheet 2) is a sectional elevation shewing my improved com-
pound valve made rectangular in form; Fig. 5 is a horizontal section
of the same; Fig. 6 is a sectional elevation at right angles to Fig. 4;
and Fig. 7 is a horizontal section of the main and cut-off valves.
a is an ordinary main valve balanced by packing rings n at the back,
and are rectangular moveable cut-off or expansion valves working in
the interior of the valve a, the main and inner valves being actuated in
a similar manner to those herein-before described.
Fig. 8 (Sheet 3) is a central vertical section of another arrangement;
Fig. 9 is a horizontal section of the same; and Fig. 10 is a vertical
section taken in the line E, F, of Fig. 9.

page_text: The construction of this arrangement will be readily understood from
the Drawings, the main valve a being of ordinary form balanced by
packing rings n and provided with circular cut-off valves b, worked
similarly to those already described with reference to previous arrange-
ments.
By arranging the ports all round the circumferences of the cylindrical
expansion valves, and on both faces of the rectangular expansion valves,
as described, the maximum area for the admission of steam or or other
expansive fluid is obtained, and at the same time the pressures on the
valve faces are completely balanced under all circumstances.
Although in the accompanying Drawings I have shewn my improved
compound valves as arranged for compound engines, it will be evident
that the valves may be placed vertically, horizontally, or at any other
angle, and that they are applicable to various descriptions of engines.
Having described my said Invention of "Improvements in Slide Valves
and Arrangements for Working the same," and having explained the
manner of carrying the same into practical effect, I claim as the
Invention secured to me by the herein-before in part recited Letters
Patent,―
First. The arranging and constructing compound slide valves so that
the pressures on all the slide faces are completely balanced, substantially
as described.
Secondly. Working the expansion or cut-off valves through a lever
connected with the piston tail rod and with the valve rod, substantially
as herein-before described and illustrated in Fig. 1 of the accompanying
Drawings.
In witness whereof, I, the said Joshua Rooke, have hereunto set
my hand and seal, this Eighteenth day of November, in the year
of our Lord One thousand eight hundred and seventy-two.