IMPROVEMENTS IN MOTIVE TOWER ENGINES
Year: 1875

page_text: LETTERS PATENT to The Right Honorable James, Earl of Caithness,
of Portland Place, in the County of Middlesex, for the Invention
.:
Monte DOWN"
of "IMPROVEMENTS IN MOTIVE TOWER ENGINES."
Sealed the 23rd May 1876, and dated the 7th December 1875.
PROVISIONAL SPECIFICATION left by the said Jamies, Earl of Caith-
ness at the Office of the Commissioners of Patents, with his
Petition, on the 7th December 1875.
I, The Right Honorable JAMES, Earl of CAITHNESS, of Portland
Place, in the County of Middlesex, do hereby declare the nature of
my said Invention for "IMPROVEMENTS IN MOTIVE-POWER Engines,” to be
as follows:
-
My Invention relates to valves for distributing the steam or other
motive fluid to the cylinders of motive-power engines and exhausting or
discharging such fluid therefrom, and it has for its object relieving the
valve from the external pressure of the motive fluid, whereby the friction
and consequent wear of the surfaces is diminished and much greater
durability is obtained.

page_text: In carrying out my Invention I employ two sliding valves, arranged
by preference side by side, one for admitting the steam (for example) to
the cylinder and the other for exhausting therefrom. Each valve
consists of an open tube fitted within a cylindrical valve box or chamber,
and having two ports or apertures in its side communicating respectively
with the two ends of the cylinder, the latter being also provided with
corresponding ports or apertures.
The steam is introduced into the interior of the steam valve or tube
through steam pipes, over or along the exterior of which the steam
valve or tube fitted with suitable stuffing boxes or packing, is caused to
slide, such steam passing through the two ports alternately into the
corresponding ends of the cylinder as the two valve ports are brought
in succession by the reciprocating motion of the valve opposite the
corresponding ports in the cylinder.
The steam after having done its duty in the cylinder by acting upon
the piston is discharged from both sides of the cylinder alternately
through the respective cylinder exhaust port into the exhaust valve or
tube as the corresponding valve exhaust port is brought opposite thereto
by the reciprocating motion of the exhaust valve or tube, such valve
sliding over or along the exhaust pipes in a manner similar to that
herein-before described in reference to the steam valve over or along the
steam pipes.
In lieu of the preceding arrangement the valves, or either of them,
may be made with closed ends, and the steam pipe or the exhaust pipe,
or both, may be fitted into the side of the valve boxes. The valves will
then simply slide along the cylindrical or flat surface of their chambers,
and the end stuffing boxes or packing may be dispensed with.
The to-and-fro reciprocating motion is imparted to the valves (which
may be connected together by a plate or otherwise) from the main shaft
through the intervention of eccentrics or cranks, and levers and con-
necting rods, in any usual or suitable manner, so as to successively open
the two steam ports and simultaneously the exhaust port of the opposite
end of the cylinder.
An additional slide forming a cut-off valve may be provided for the
purpose of closing the steam ports when the piston has performed any
required portion of its stroke so as to cause the steam to work expan-
sively for the remainder of the stroke, such valve being actuated in any

page_text: convenient manner either directly from the driving shaft or from the
-steam admission valve or otherwise.
In the case of locomotive or marine engines, or for other engines,
when desirable the steam valve may be itself so arranged as to admit of
the steam being cut off at any required portion of the stroke of the
piston without the employment of a separate expansion valve, and
reversing gear may also be provided for the facility of working the
engine in opposite directions.
These valves may all be made flat as well as round, or also the same
shape as the D valve; in fact, of any shape suitable to the requirements
of the work to be done.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James, Earl of Caithness, in the Great Seal Patent
Office on the 7th June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, The Right
Honorable JAMES, Earl of CAITHNESS, of Portland Place, in the County
of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of December, in the
year of our Lord One thousand eight hundred and seventy-five, in the
39th year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said James, Earl of Caithness, Her special
license that I, the said James, Earl of Caithness, my executors, admini-
strators, and assigns, or such others as I, the said James, Earl of
Caithness, my executors, administrators, or 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 Kingdoni
of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN MOTIVE-POWER ENGINES," upon the
condition (amongst others) that I, the said James, Earl of Caithness,
my executors or administrators, by an instrument in writing under
any hand and seal, should particularly describe and ascertain the

page_text: 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 James, Earl of Caithness, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer
tained in and by the following statement, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon,
that is to say :-
My said Invention relates to valves for distributing the steam or other
motive fluid to the cylinders of motive-power engines and exhausting or
discharging such fluid therefrom, and it has for its object relieving the
valve from the external pressure of the motive fluid whereby the friction
and constant wear of the surfaces is diminished and much greater
durability is obtained.
In order to effect this object I employ sliding valves of a cylindrical
or flat section, as herein-after described, and I admit the motive fluid
to their interior in lieu of at their exterior as in the ordinary method.
And in order that my said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that
purpose shall refer to the several Figures on the annexed two Sheets of
Drawings, the same letters of reference indicating corresponding parts
in all the Figures.
Figure 1 (Sheet 1) of my Drawings represents a longitudinal section
of a portion of a cylinder with my Invention applied thereto according
to one mode of carrying out the same; Figure 2 is a transverse section;
and Figure 3 a plan, both corresponding to Figure 1.
Figures 4 and 5 (Sheet 1), and Figures 6, 7, 8, and 9, Sheet 2, are
views illustrating various modifications, which will be herein-after
referred to.
According to the arrangement illustrated in Figures 1, 2, and 3, I
employ two sliding valves A, B, arranged side by side, the one A being
for admitting the steam (for example) to the cylinder C, and the other
B for exhausting therefrom. The steam valve A consists of an open
tube fitted within a cylindrical valve box or chamber D, and having two

page_text: ports or apertures a, a², in its side communicating respectively with the
two ends of the cylinder C, the latter being also provided with corre-
sponding ports or apertures b, b¹.
The exhaust valve B is constructed in a similar manner, it consisting
of an open tube fitted within the valve box or chamber D, and having
two ports or apertures c, c¹, communicating respectively with the two
ends of the cylinder O, which is also provided with corresponding ports
or apertures d, d¹.
The steam is introduced into the interior of the steam valve or tube A
through steam pipes E, E, over or along the exterior of which the steam
valve or tube A, fitted with suitable stuffing boxes or packing e, e, is
caused to slide, such steam passing through the two ports 6, 61, alter-
nately into the corresponding ends of the cylinder as the two valve
ports a, a, are brought in succession by the reciprocating motion of the
valve A opposite the corresponding ports b, b, in the cylinder.
The steam after having done its duty in the cylinder C by acting upon
the piston F is discharged from both sides of the cylinder alternately
through the respective cylinder exhaust port d or d', as the case may be,
into the exhaust valve or tube B as the corresponding valve exhaust
port c or c¹ is brought opposite thereto by the reciprocating motion of
the exhaust valve or tube B, such valve sliding over or along the exhaust
pipes G, G, fitted with stuffing boxes or packing f, f, in a manner similar
to that herein-before described in reference to the steam valve over or
along the steam pipes.
The to-and-fro reciprocating motion is imparted to the valves (which
may be connected together either by a plate H, as shewn in my Drawing
or otherwise) from the main shaft through the intervention of the con-
necting rod I and eccentrics, or cranks and levers, in any usual or suitable
manner, so as to successively open the two steam ports, and simul-
taneously the exhaust port of the opposite end of the cylinder.
According to a modification of the preceding arrangement, which is
illustrated in longitudinal section in Figure 4, the steam valve A is made
with closed ends, as shewn at e, e, and the steam pipe E is fitted into
the cover of the valve box D. The valve will then simply slide along
the cylindrical surface of its chamber, the end stuffing boxes or packing
being dispensed with. The exhaust valve may also be constructed
and arranged in a similar manner.

page_text: .
·
Figure 5 is a transverse section illustrating one mode of applying
valves of a flat form in accordance with my Invention. In this arrange-
ment the steam valve A. consists of a sliding tube of rectangular section,
having ports or apertures communicating with the cylinder, as herein-
before described, and the exhaust valve B is constructed of similar form,
and is also provided with the requisite ports or apertures.
According to another modification, which is illustrated by the longi-
tudinal and horizontal sections, Figures 6 and 7 respectively (Sheet 2),
I dispense with the separate exhaust valve and utilize the steam valve
for regulating the discharge of the exhaust steam as well as for dis-
tributing the live steam to the cylinder. For this purpose I con-
struct the. flat valve in the form of a tube A of rectangular_section
with closed ends e, e, and fit it so as to be capable of sliding within a
closed valve box or chamber D. The valve is provided with stems g, g',
adapted to suitable guides in the ends 1, 2, of the valve box or chamber,
the stem g¹ passing through a stuffing box and extending beyond the
ond so as to receive the connection with the actuating shaft.
The steam is admitted by the pipe E to the interior of the valve A,
and passes alternately through the valve ports a, a, and the cylinder
ports b, b', into the cylinder C, and after having performed its duty in
the cylinder it passes into one or other of the chambers k, k², into which
the valve box is divided by the valve A, and exhausts therefrom through
the pipes G, G¹, into the atmosphere or a condenser or elsewhere as
required. In the position of the parts indicated by the black lines in my
Drawings the steam is assumed to be passing through the valve port a
and cylinder port b into the left-hand end of the cylinder and exhausting
from the right-hand end of the cylinder into the chamber ¹, and thence
by the pipe G into the atmosphere or into a condenser or clsewhere as
required. When the valve is reversed and brought into the position
indicated by red lines in the Drawing, the steam from the left-hand side
of the piston F will exhaust into the chamber and be discharged there-
from by the pipe G, whilst the live steam supplied by the pipe E to the
chamber in the interior of the valve A will pass through the valve
port a¹ and cylinder port b' into the opposite end of the cylinder Cat
the right-hand side of the piston F, and so on in succession. .
According to a further modification, which is illustrated by the longi-
tudinal and horizontal sections, Figures 8 and 9 respectively, Sheet 2, I

page_text: simplify the apparatus by dispensing with the sides of the valve and
retaining simply the ends e, e, which are connected by a continuation g²
of the stems g, g', and together constitute the valve. The apparatus
operates in a similar manner to that described with reference to the
arrangement in Figures 6 and 7.
.
Assuming the valve to be in the position indicated by black lines in
the Drawing, the steam entering by the pipe E, the chamber i between
the two constituent portions e, e, of the valve passes direct through the
cylinder port to the left-hand side of the piston F, whilst the steam
from the right-hand side of the piston exhausts through the cylinder
port 6 into the chamber k³, and thence escapes by the exhaust pipe G³.
The valve then being reversed by the action of the engine and brought
into the position indicated by the red lines, the steam entering the
chamber i passes direct through the cylinder port to the right-hand
side of the piston, whilst the steam from the left-hand side of the piston
exhausts through the cylinder port 6 into the chamber k, and thence
escapes by the exhaust pipe G. The valve being then again reversed,
the former operation is repeated, and so on in succession.
It will be obvious that as the steam admitted to the chamber i between
the two portions e, e, of the valve exercises its pressure equally on both
sides the friction and consequent wear to which slide valves when con-
structed in the ordinary manner are subjected are greatly diminished,
and much greater durability is obtained. The valve may be maintained
steam-tight by any ordinary or suitable means. I have slewn in my
Drawings two modes. of effecting this object, one of which is represented
in Figures 6 and 7, and the other in Figures 8 and 9. The arrangement
shewn in Figures 6 and 7 consists of lining plates 1, ; fitted loosely in
the cover and sides respectively of the valve box D, and adjusted by
means of set screws m, m². I prefer, however, to adopt the modification
shewn in Figures 8 and 9, which consists in the employment at the top
and sides of the valve of loosely fitting plates 2, 1, and forming passages
n, n', through the body of the valve so as to admit steam under or at
the rear of the plates 1, 1, in order by its pressure to force them into
contact with the cover and sides respectively of the valve box D, and
thereby maintain a steam-tight joint.
An additional slide forming a cut-off valve may be provided for the
purpose of closing the steam ports when the piston has performed any
required portion of its stroke so as to cause the steam to work expan-

page_text: sively for the remainder of the stroke, such valve being actuated in any
convenient manner either directly from the driving shaft or from the
steam admission valve or otherwise.
In the case of locomotive or marine engines, or for other engines,
when desirable the steam valve may be itself so arranged as to admit of
the steam being cut off at any required portion of the stroke of the
piston without the employment of a separate expansion valve, and
reversing gear may also be provided for the facility of working the
engine in opposite directions.
Having now described and particularly ascertained the nature of my 1
said Invention and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that I do not claim
generally the use in motive-power engines of distributing valves in
which the motive fluid is admitted to the cylinder through the interior
of the valve, but what I consider to be novel and original, and therefore 1
claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. Constructing distributing valves in which the motive fluid is
admitted to the cylinder through the interior of the valve, substan-
tially in the manner herein-before described and illustrated by my a
Drawings.
Secondly. The combination of the tubular inlet valve A and the
tubular exhaust valve B, substantially as herein-before described and
illustrated by Figures 1, 2, 3, 4, and 5 of my Drawings.
In witness whereof, I, the said James, Earl of Caithness, have i
to this my Specification set my hand and seal, this First day
of June, One thousand eight hundred and seventy-six.
ATTENTION