IMPROVEMENTS IN STEAM ENGINES
Year: 1855

page_text: LETTERS PATENT to William Rowan, of the firm of J. Rowan and
Sons, of Belfast, in the County of Antrim, Engineers, for the Invention
of "IMPROVEMENTS IN STEAM ENGINES."
Sealed the 29th April 1856, and dated the 3rd December 1855.
PROVISIONAL SPECIFICATION left by the said William Rowan at the
Office of the Commissioners of Patents, with his Petition, on the 3rd
December 1855.
1, WILLIAM ROWAN, of the firm of J. Rowan and Sons, of Belfast, in the
County of Antrim, Engineers, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN STEAM ENGINES" to be as follows:-
My Invention consists, first, in a novel arrangement of the parts of steam.
engines, whereby great compactness and strength are obtained, intended prin-
cipally for driving the screw propeller of steam vessels. In this arrangement
the cylinders of a pair of engines are placed at an angle of 45 degrees with a
vertical line, and are bolted to the upper two faces of a triangular vessel of cast
iron, which also forms the condenser for the steam.
"1
My Invention further consists in the introduction of a valve or valves, in.
addition to those now in use in condensing steam engines, and also an addi-;
tional condenser with which these valves communicate. These valves are;
made to open for a short time immediately before the end of the piston's
stroke, and a small quantity of injection water is introduced into the extra con-

page_text: denser, just sufficient to condense the steam, without producing more than a
very partial vacuum. A quantity of water at nearly the boiling point is thus
obtained, which is used for feeding the boiler, whereby an economy of fuel is
produced, and the main condenser has less work to do in condensing the
remaining portion of the steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filod
by the said William Rowan in the Great Seal Patent Office on the
30th May 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROWAN, of the firm of J. Rowan and Sons, of Belfast, in the County of
Autrim, Engineers, send greeting.
i
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of December, in the year of our Lord One
thousand eight hundred and fifty-five, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Rowan, Her special licence, that I, the said William Rowan, my
exceutors, administrators, and assigns, or such others as I, the said William
Rowan, 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 STEAM ENGINES,"
upon
the condition (amongst others) that I, the said William Rowan, 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 William Rowan, 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 thereof, reference being had to the Drawings hereunto annexed,
that is to say:-
"
My Invention' consists in a new or improved arrangement of the parts of

page_text: steam engines, whereby great compactness and strength are obtained, intended
principally for driving the screw propeller of steam vessels. In this arrange-
ment the cylinders of a pair of engines are placed at an angle of 45 degrees
with a vertical line, that is to say, at an angle of 90° with each other, and are
bolted to the upper two faces of a triangular vessel of cast iron, which also
forms the condenser for the steam.
My Invention further consists in the introduction of a valve or valves, in
addition to those now in use in condensing steam engines, and also of an addi-
tional condenser with which these valves communicate. These valves are made
to open for a short time immediately before the end of the piston's stroke, and
a small quantity of injection water is introduced into the additional condenser,
just sufficient to condense the steam, without producing more than a very
partial vacuum. A quantity of water at nearly the boiling point is thus
obtained, which is used for feeding the boiler, whereby
an economy of fuel is
produced and the main condenser has less work to do in condensing the
remaining portion of the steam; or the water obtained may be used for any
other purpose.
I now proceed to describe, with reference to the accompanying Drawings,
the first part of my improvements, consisting of a new arrangement of the
parts of steam engines, in which the cylinders are at an angle of 90° to each
other, and bolted to the condenser.
Figure 1 is an end view partly in section, of a pair of steam engines con-
structed according to these improvements; Figure 2 is a side view of the same,
partly in section; and Figure 3 is a ground plan, having likewise some por-
tions in section, for the purpose of shewing the internal details. The same
letters of reference are used for the same parts in each of these three Figures.
A, A, are the cylinders, placed at an angle of 90 degrees, or thereabouts, with
each other; B is the condenser, which also serves for the framework of the engine;
D, D, are pedestals or bearings cast on the condenser, for carrying the crank
shaft. This condenser is formed with the two opposite sides inclined towards cach
other, and meeting at the top at a right angle, and upon these sides the cylinders
are bolted by means of flanges cast longitudinally on the cylinders which lie upon
the condenser, a recess or groove being cast on each of these sides of the con-
denser of a suitable form aud size to receive the projecting flanges on the under
side of the cylinders. E, E, are hollow piston rods or trunks, to which the
pistons F are attached, and having a joint pin at the lower end, on which the
connecting rod G works. The connecting rods of both engines work into one
crank H. At one end of the crank shaft is fixed a crank I, for the purpose of
working the air pump J and the boiler and bilge pumps K, K, by means of a

page_text: connecting rod a and crosshead b. These three pumps are placed verti-
cally, and are bolted down to a flange g cast on the condenser for this purpose,
and also for affording a secure foundation for the whole engine. c is the foot
valve; d, the air pump bucket; e, the delivering valve; and f, the hot well.
I., L, are the valve boxes containing the valves h, h, for the admission of steam
to the upper and lower ends of the cylinder; and i, i, are the valves for the
exit of the same to the condenser; these are of the well-known double-beat
form or Cornish" valves, and are worked by the arrangement known as
Rowan's fluctuating slider, which was registered by me on the Twenty-ninth
September, One, thousand eight hundred and forty-eight, under the " Designs'
Registration Act." M is a cam shaft,,on, which are mounted cams h, k,^, k'.
Two of these cams, namely, k² and ", act on the fluctuating sliders 1, lifting the
square frames m, m, and the valves h,h; attached to them. Each slider is
capable of being pushed further in or withdrawn from the frame through the
medium of the lever n, a slot being formed in the end of the slider to allow the
valve and attachments to rise, without affecting the position of the slider in its
frame, thus allowing the valve to fall later or earlier, as may be desired, and
consequently shutting off the steam later or earlier, and so varying at pleasure
the degree of expansion of the steam in the cylinder. The cams k¹ and k also
act on the exhaust valves i, i, but have no sliders, the part of the frame on
which they act being fixed. j.j, are additional valves, the employnient of
which forms, a portion of the second part of my Invention; but they may or
may not be used; in connection with this part of my Invention. .O' is a bevil
wheel, fixed on the crank shaft, and giving motion to the bevil wheel O" on the
short upright shaft q.. On the lower end of this upright shaft is fixed the bevil
wheel pl, imparting motion to the two bevil wheels p² and p³ in reverse direc-
tions; these wheels may be all of one size, or their sizes may be different, so
that the wheels p², and p³ may revolve in the same time as the crank shaft.
The wheels p² and p revolve loosely on the cam shaft between collars, and
between them is a clutch r, capable of sliding on end on the cam shaft, but
prevented from revolving independently of the shaft by a feather or key fixed
on the latter. This clutch is acted upon by the lever 8, attached to the two,
levers and, by which means the clutch becomes fastened to either the
wheel por p, and the cam shaft is made to partake of the movement of
either one of these wheels at pleasure. The clutch has but one tooth on each
side, and the cams are so adjusted as regards these teeth, that while one tooth
is set for giving the valves the right motion for the engine going forward, the,
other one will be right for the engine going backward. Thus, the engine is
reversed by depressing either the one or the other of the levers t' or . The cam

page_text: shaft will always revolve in the same direction, inasmuch as its relative motion
as regards the crank shaft is changed by the clutch and bevil wheels when the
direction of the motion of the crank shaft is changed; but to prevent the cam
shaft from getting a wrong motion in the act of reversing the engines, which
wrong motion would cause the points of the cams to catch against the points
of the sliders, and so injure the machinery, the teeth of the clutch are
bevilled on the side opposite to that on which they drive the wheels, and con-
sequently the clutch will be thrown out of gear in the event of such a wrong
movement taking place. u, u, u, are springs, acting on the top of the frames
of the valves, to assist in closing the valves when their own weight is not
capable of closing them with sufficient rapidity; but except in the case of
engines revolving very rapidly these springs are not requisite.
I now proceed to describe the second part of my Invention, which consists
in the employment or introduction of a valve or valves in addition to those now
in use for the exit of the steam from the cylinders of condensing engines, and
also in the employment of an additional condenser with which these valves
communicate. In this supplementary condenser a portion of the steam from
the cylinder is condensed, but the quantity of cold water admitted for con-
densing is no more than will just do so; hence I obtain a quantity of water at
nearly a boiling temperature, which I use for the purpose of feeding the boiler,
whereby a better vacuum is obtained in the main condenser.
In Figures 1, 2, and 3, I have shewn one method I employ in carrying out
this part of my Invention. h, h, and i, i, represent the usual steam and exhaust
valves; and j,j, are my additional exhaust valves, one of which is in connection
with each end of the cylinder; they are worked by cams on the same shaft as
those which lift the ordinary valves. C is a chamber, cast in the main con-
denser, and serving as an additional condenser; there is also a similar
condenser formed in the opposite corresponding side of the main condenser.
These two additional condensers are connected by the passage w under the
main condenser. The valves j,j, are in connection with these auxiliary con-
densers, and a jet of water from either the hot well f, or elsewhere, regulated
by a valve or cock, is admitted into each of these condensers in just sufficient
quantity to condense the steam issuing through the valves J, J, without
producing more than a very partial vacuum.
The hot water thus obtained is conveyed to the boiler by one of the
pumps
K, K, and the quantity necessary to maintain the water in the boiler at its
proper level is regulated by the valves or cocks which admit the jets into the
auxiliary condensers. The valves J, J, are opened for a short time only before
the termination of the stroke, commencing some time after the corresponding

page_text: steam valve has closed, and closing immediately before the corresponding main
exhaust valve begins to open. The length of time they remain open is deter-
mined by the quantity and temperature of the feed water required; but I find
that from a fourth to a third part of the whole stroke is a very good
proportion.
In applying this part of my Invention to engines in which it is desired to
retain the, ordinary valves, I adopt the arrangement represented in Figures 4
and 5. Figure 4 is an elevation of a cylinder of an engine, the ordinary
valves of which are not shewn, as they are not in any way interfered with by
my improvements. Figure 5 is a section of the same, taken at right angles to
Figure.4. N is the auxiliary condenser, into which the exhaust steam is
admitted by the valves P, P, which are alternately opened by the cams Q (ono
only of which is shewn in the Drawing) a short interval before the termination
of the stroke, as before described. R is the injection cock; and S, the orifice of
the pipe, through. which the hot water formed by condensing the steam is
conveyed to the feed pump, and thence to the boiler.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim,-
Firstly, the combination and arrangement of the various parts of steam
engines described in the first part of this Specification, or any modification
thereof, which would be substantially the same.
Secondly, 1 claim the employment and adaptation of a valve or valves, whe-
ther of the particular kind herein-before described or not, and of a condenser
or condensers, as described herein, such valve or valves, and condenser or con-
densers, being used for condensing a portion of the steam, and producing water
of a high temperature for supplying the boilers, or for any other purpose; the
said condenser or condensers being supplementary to the usual .condenser in
which the vacuum is formed. .
In witness whereof, I, the said William Rowan, have hereunto set my
hand and seal, this Twenty-second day of May, One thousand eight
hundred and fifty-six.
WILL ROWAN. (L.S.)