IMPROVEMENTS IN STEAM ENGINES, WITH A GENERAL ARRANGEMENT OF VALVES FOR THE INGRESS AND EGRESS OF THE STEAM, AND THE MODE OF APPLYING AND WORKING SAME.
Year: 1873

page_text: LETTERS PATENT to William Rowan, of Belfast, in the County of
Antrim, Engineer, for the Invention of "IMPROVEMENTS IN STEAM
ENGINES, WITH A GENERAL ARRANGEMENT OF VALVES FOR THE INGRESS
AND EGRESS OF THE STEAM, AND THE MODE OF APPLYING AND WORKING
SAME.
"
Sealed the 12th December 1873, and dated the 27th June 1873.
.
PROVISIONAL SPECIFICATION left by the said William Rowan at the
Office of the Commissioners of Patents, with his Petition, on the
27th June 1873.
I, WILLIAM ROWAN, of Belfast, in the County of Antrim, Engineer,
do hereby declare the nature of the said Invention for “IMPROVEMENTS IN
STEAM ENGINES, WITH A GENERAL ARRANGEMENT OF VALVES FOR THE INGRESS AND
EGRESS OF THE STEAM, AND THE MODE OF APPLYING AND WORKING SAME," to
be as follows:-
These improvements relate to the arrangement of machinery in con-
nection with the using of steam of a high pressure, and the mode in
which such steam is inducted to and educted from the cylinders..

page_text: The Invention consists mainly in the employment of an equilibrium
double beat valve and sliding exhaust valve working in conjunction with
cach other, and each wrought by the same tappet shaft, and in the
particular arrangement of the tappet by which the sliding exhaust valve
is wrought; also in the employment of a certain number of cylinders.
In using steam of a high pressure, say from 90 to 100 lbs. per square
inch, I cut off same at any grade of expansion, either fo,,, according
to the power required, and educt the steam from the same cylinder
direct into the condenser. But in the case when one or even two cylin-
ders are employed, the using of high-pressure steam is detrimental,
causing great irregularity in their working, to obviate which I propose
to adopt the use of three cylinders, by which means the supply of steam
is equally divided; imparting great regularity of motion, and being the
means of using high-pressure steam to the highest grade of expansion.
with safety and advantage.
The steam valve is of the double beat description equilibrium, and is
wrought by a tappet and fluctuating sliders (for which a Patent was
granted me some years ago).
The sliding exhaust valve consists of a plain block placed close to the
steam valve, and in the same box, with its face reversed to the pressure
of steam, by which means the face is kept tight by the steam acting on
the back. There are two of these exhaust valves, and two steam valves,
a pair of which, that is, steam and exhaust, are placed at each end of the
cylinder. The two exhaust or sliding valves are connected by one
spindle, in the middle of which is placed a tappet of a peculiar kind so
arranged as to open and shut the valve instantly, keeping it shut to the
condenser during the time the steam valve is supplying steam to the
cylinder. By this arrangement of tappet and frame, a superiority is gained
over the adoption of an eccentric, as the friction caused by the movement
of the valve is obviated, which would not be the case in the employment
of an eccentric motion. By the arrangement of these valves only two
ports in the cylinder would be required, and the whole is rendered
simple, economical in manufacture, and very effective in the economizing
of fuel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Rowan in the Great Seal Patent Office on
the 24th December 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROWAN, of Belfast, in the County of Antrim, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of June, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth 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 executors, 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, usc, 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, WITH A
GENERAL ARRANGEMENT OF VALVES FOR THE INGRESS AND EGRESS OF THE STEAM, AND
THE MODE OF APPLYING AND WORKING SAME," 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 thercof, reference being had to the Drawings here-
unto annexed, that is to say :-
These improvements relate to the arrangement of machinery in con-
nection with the using of steam of a high pressure, and the mode in
which such steam is inducted to and educted from the cylinders.
The Invention consists mainly in the employment of equilibrium.
double beat valves and sliding exhaust valves, working in conjunction

page_text: with each other, and each wrought by the same tappet shaft, also in the
particular arrangement of the tappet by which the sliding exhaust valve
is wrought, and by the employment of a certain number of cylinders,
with one condenser and air pump common to all.
I prefer to use steam of high pressure, say from 90 to 100 lbs. per
square inch, and to cut off the same at any grade of expansion, either
8, 10, or, according to the power required, and to educt the steam
from the same cylinder direct into the condenser. But in the case when
one or even two cylinders are employed the using of high-pressure steam
is detrimental, causing great irregularity in their working, and to obviate
which I use in most cases three cylinders, a double-cranked shaft, and
two single cranks, the connecting rod of middle cylinder being connected
to the double crank and the connecting rods of the two outer cylinders
each to a single crank. These cranks are equally divided in three points
of the circle around which they travel to permit of the supply of steam,
which will be equally divided between the three cylinders, thus imparting
great regularity of motion, and facilitating the using of high-pressure
steam to the highest grade of expansion with perfect safety and
advantage.
The steam valve is of the double beat description equilibrium, and is
wrought by a tappet and fluctuating slider.
The sliding exhaust valve consists of a plain block placed close to the
steam valve, and in the same steam chest, with its face reversed to the
pressure of the steam, which acts on the back, and ensures the face
being kept tight. There are two steam chests for each cylinder, one for
the upper and one for the lower port. In each one of these two chests
are placed a pair of valves, that is, steam and exhaust. In this case the
upper and lower chests are connected by side pipes, one being the steam
and the other the exhaust. These side pipes become available for
supporting the pedestals for carrying the tappet shaft, and the necessary
guides required for the valve frames; the two exhaust or sliding valves.
are connected by one spindle, in the middle of which is a square frame,
in which is placed a tappet of a peculiar kind so arranged as to open and
shut the valve instantly, keeping it immovably shut to the condenser
during the time the steam valve is supplying steam to the cylinder. By
this arrangement of tappet a superiority is gained over the adoption of an
excentric, as the friction caused by the movement of the valve with the

page_text: pressure of steam on it is obviated, which would not be the case in the
employment of an excentric motion. By the arrangement of these
valves only a port in each end of the cylinder is necessary, and the
whole is rendered simple, economical in manufacture, and very effective
in the economizing of fuel.
In the annexed Drawings, Sheets 1 and 2, my improvements are
shown as applied to vertical engines only, but it is not intended to adopt
this plan in any cases of modern engines. It is my intention only to
make use of it by attaching it to the cylinders of existing engines which
may require any alteration or improvements in the way of superseding
the ordinary slide valve.
The next part of my improvements consists in the employment of
these valves not only for vertical but for horizontal engines, and for
the adaptation of which I intend to place the whole of the four valves,
that is to say, the two steam and two exhaust, into one chest, the
efficiency and actuations being the same as already described. By the
employment of this one valve chest I can appropriate my improvements
any kind of modern engines, whether horizontal or vertical.
to
Sheet 3 of the annexed Drawings will illustrate this form of valve
chest, showing also the position the valves are placed therein, and by
the arrow marks the induction and eduction of the steam will be clearly
shown. This Drawing shows the valve chest as applied to vertical
engines, its application to horizontal requiring no explanation. In
adopting this form of valve chest to vertical engines I dispense with the
steam and exhaust side pipes, and substitute standards to support the
pedestals for carrying the tappet shaft and guides for the valve frames
previously described.
In the accompanying Drawings Sheet No. 1, Figure 1 shows a cross
section, and Figure 2 a front elevation of the engines complete.
Sheet No. 2, Figures 3, 4, and 5 are details. The same letters are
employed on all the Figures to indicate the same meaning.
In Figures 1, 2, and 4, A are the cylinders supported on suitable
standards; B, the double cranks; C and D, the two single cranks, all
shown divided in three parts of the circle around which they travel; E
is the middle rod connected to the double crank; F and G, the other two
connected to the two outer cranks; H is the condenser; and I the air
t

page_text: pump wrought by a lever from the cross head of middle connecting rod;
J, Figures 1 and 2, are different views of the two valve chests, upper and
lower end; and Figures 3 and 4 enlarged views of same; K are the
double beat steam valves; L, the tappets for working the same; M, the
fluctuating sliders; N, the frames in which they are placed; Figure 5
shows an enlarged view of same%;B O are the sliding exhaust valves,
shown with their faces P reversed to the pressure of steam; Q, the
tappets for working same, showing the peculiar form already referred to;
R, the spindles and square frames in which the tappets are placed; S,
the tappet shafts, which receive motion from the crank shafts by bevil
wheels; T are the steam, and U the exhaust side pipes, with brackets for
supporting tappet shaft pedestals V and guides W for steam frames N
and exhaust frames R, as all previously described.
On Figure 2 is shown a method of reversing which I propose to adopt
in case these improvements may be extended to marine purposes.
On the upper end of an upright shaft x, leading from and wrought by
the crank shaft, is keyed a bevil wheel Y, imparting motion to two bevil
wheels Z' and Z³, in reverse directions. These wheels revolve loosely on
the tappet shaft S, between collars a, and between them is a clutch b,
capable of sliding on end on the tappet shaft, but prevented from
revolving independently of the shaft by a feather or key fixed on the
latter. The clutch 6 is acted upon by the lever c attached by a
bar to the reversing handle d, by which means the clutch becomes
fastened to either of the wheels Z¹ or Z³, and the tappet 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 tappets 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 will be right for
the engine going backward; thus the engine is reversed by depressing
or raising the handle d, the tappet shaft will always revolve in one
direction, while the motion of the crank shaft will be changed.
On Sheet No. 3 Figures 6 and 7 are two views of the other part of
my improvements, as described previously. e is the cylinder; f, the one
valve chest; g, the double beat steam valves; h, the frames in which
the tappets and slider for same are placed; i are the sliding exhaust
valves, with their faces placed reverse to the steam pressuro; j, the
exhaust tappet already referred to; k, the frames in which the said

page_text: tappets are placed, but in this case constructed similar to the steam
tappet frames; 7, the tappet shaft; m, the standards for supporting
tappet shaft pedestals, and guides for steam and exhaust frames, in licu of
the side pipes described previously; n are the ports for conveying the
steam to each end of the cylinder; o is the steam pipe; and p the
exhaust pipe.
Having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim,—
Firstly. The improvements in steam engines, all as herein-before
described and shown.
Secondly. I claim the arrangement and combination of valves by
which high-pressure steam is employed with advantage, and by which a
regularity of motion is obtained in engines not hitherto attainable, both
as herein-before set forth and shown.
Thirdly. I claim the employment of equilibrium double beat valves
and sliding exhaust valves, working in conjunction and operated by
single tappet shafts in the manner and for the purpose described and
shown.
Lastly. I claim the special arrangement of tappet described and shown
when such tappet is employed for operating sliding valves of steam
engines.
In witness whereof, I, the said William Rowan, have hereunto set
my hand and scal, this Nineteenth day of December One thousand
cight hundred and seventy-three.
TUTT TM DAT