IMPROVEMENTS IN ENGINES TO BE ACTUATED BY STEAM, AIR, OR GASES
Year: 1858

page_text: LETTERS PATENT to James Davis, Iron Master, and Thomas Evans,
Engine Fitter, both of Ulverston, in the County of Lancaster, for the
Invention of "IMPROVEMENTS IN ENGINES TO BE ACTUATED BY STEAM, AIR,
OR GASES."
Sealed the 5th January 1859, and dated the 6th July 1858.
PROVISIONAL SPECIFICATION left by the said James Davis and Thomas
Evans at the Office of the Commissioners of Patents, with their Petition,
on the 6th July 1858.
We, JAMES DAVIS, Iron Master, and THOMAS EVANS, Engine Fitter, both
of Ulverston, in the County of Lancaster, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN ENGINES TO BE ACTUATED BY STEAM, AIR,
OR GASES," to be as follows:-.
The object of our Invention of improvements in engines to be actuated by
steam, air, or gases, is to dispense with the use of the excentrics or other goar
now employed to move the slide valves of engines. Our Invention is intended
to be applied to oscillating engines, in which the cylinder is mounted in bearings
on hollow axles through which steam is admitted to the interior. of the cylinder,
and the exit steam passes to the exhaust. In our improved engine. the
cylinder is cast with the valve chest upon it, which also serves as a journal for
the cylinder to work or oscillate- upon. The valve is attached to a stem and
handle, which enables it to be fastened or fixed where required. The valve is
pierced for two steam ports, the exhaust port being. a recessed hollow in one
half of the valve, which is kept in its place and prevented from moving
laterally by the end of the vertical stem being made to project through the
.

page_text: valve, and fit into a hole in the valve seat. The valve is kept in contact with its
seat by the pressure of the steam upon it. The steam pipe is turned and fixed
in the valve seat or steam chest by a gland and stuffing, and the stem of the
valve also passes through a gland properly packed. The steam ports into the
cylinder are placed opposite to each other, while those in the valve are not
opposite to each other, but are so arranged that while one is over the port into
the cylinder the other is over a blank place.
It will be understood that the valve itself is fixed while the engine is at
work, and the ports are opened and closed by the oscillation of the cylinder
on its axle, whereby the ports of the cylinder are alternately brought opposite
to or into coincidence with the ports of the valve. In order to reverse the
action of the engine the valve is simply to be turned half round by means of
the handle, two exhaust ports being made on the cylinder, but both leading to
the opposite journal to that in which the valve chest is, the one not in use being
covered by the blank part of the face of the valve. Both the steam and exhaust
pipes are fixed independently of the engine, and have freedom to work in the
joint with the cylinder..
It will, however, be evident to any engineer that these arrangements of
parts admit of modification, without departing from the essential features of
the Invention, which may be briefly stated to consist in the use of the fixed
valve, the opening of the ports, and the admission of steam through them,
which is effected by the oscillation of the cylinder, without the intervention of
excentric or other gearing.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Davis and Thomas Evans in the Great Sear Patent
Office on the 6th January 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
DAVIS, Iron Master, and THOMAS EVANS, Engine Fitter, both of Ulverston, in
the County of Lancaster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of July, in the year of our Lord One thou-
sand eight hundred and fifty-eight, in the twenty-second year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto us, the said James
Davis and Thomas Evans, Her special licence that we, the said James Davis
and Thomas Evans, our executors, administrators, and assigns, or such others
as we, the said James Davis and Thomas Evans, our executors, administrators,

page_text: 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 ENGINES TO BE ACTUATED BY STEAM, AIR, OR GASES,"
upon the condition (amongst others) that we, the said James Davis and
Thomas Evans, our executors or administrators, by an instrument in writing
under our, 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 we, the said James Davis and Thomas Evans, do
hereby declare the nature of our said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement, that is to say:-
We construct our engines so as to have the cylinder to oscillate upon hollow.
trunnions, the steam being supplied through the said trunnions to the cylinder,
and distributed alternately to the steam passages, by means of a fixed valve
placed in the valve chamber, the rear face of which is always in contact with
the steam from the steam pipe, the other face fitting close over the steam and
exhaust ports in the side of the cylinder. This fixed steam valve has ports or
openings cut in its face at regulated distances apart, also a hollow recess. As.
the cylinder oscillates, these openings in the fixed valve coinciding with the
ports of the steam passages alternately supply each with steam, while the
recessed part in like manner puts the exhaust in communication with either
steam port. The steam passages occupy the usual position in the side of the
cylinder, and the exhaust is formed by a passage in a belt cast half round the
outer surface of the cylinder, so that the steam is received at.one side of the
latter, and discharged at the other. By having a similar exhaust passage
round the other corresponding half of the cylinder, and causing the valve to
traverse half a circle, the action of the engine may be reversed.
In order more clearly to explain the nature of our Invention, and render it
clear and intelligible, the accompanying Drawings are appended to this Specifi-
cation, but we wish it understood that in shewing the application of our
Invention to the particular arrangement of engine shewn, we do not by any
means confine ourselves to such form, but to every class of engine where the
arrangement is such as to allow of the application of the principles of our
Invention, as before mentioned, and herein-after more fully described.

page_text: Figure 1 is a plan of the engine; Figure 2, an elevation of the same,
shewing a transverse section of the valve chamber, the valve being supposed to
be in its place, the ports of the steam passages and exhaust on the valve seat
underneath being in dotted lines, as also is the recess in the valve; Figure 3
is a cross section on the line x, x'; Figure 4, a longitudinal section on the
line y, y Figure 5 is an elevation of the cylinder, shewing the form and
position of the steam and exhaust ports, and the corresponding passages;
Figure 5 is a plan shewing the inner face of the fixed valve, with the ports or
openings for steam, and the recess for the exhaust.
Similar letters indicate the same or similar parts in different Figures;
where A, A, is the cylinder oscillating on the hollow trunnions B, B, which are
seated on the plummer blocks B', B'; G, the belt cast round the cylinder, forming
the exhaust passages c¹, c²; d, the stuffing box, with the gland e, through which
passes the steam pipe f, which is turned to fit the gland e; the collar at the
end being put on after the gland has been slipped over; g is the fixed steam
valve, fitted to the valve seat on the cylinder; a and b are the two steam ports
in the seat on the cylinder; a¹ and 6, the corresponding steam ways in the
valve g (see Figures 2, 5, and 5"); c is the recess covering the exhaust, and
isolating it from each steam port alternately; c¹, c², are the exhaust passages;
in the Drawing two are shewn; this, however, is not absolutely necessary, but
they give the advantage of enabling the engine to work in either direction; g'
is the spindle of the valve g, which passes through the stuffing box h, on the
end of the steam pipe, and has a lever g² attached to it, by means of which the
valve may be caused to rotate on the seat in the valve chamber. The exhaust
tube K on the opposite side of the cylinder is turned to fit the trunnion, and
let into its place similarly to the steam pipe.
The action of this arrangement is as follows:-Suppose the engine to be
working so as to drive the wheel in the direction of the arrow shewn thereon,
the piston being at the end of the stroke, the cylinder will be passing from the
horizontal about the centre of the axis of oscillation, each end describing the
arc, and moving in the direction shewn by the arrows (see Figure 2); then
the port a, which previously has been exhausting; will now begin to take
steam, which it obtains through the oscillation of the cylinder in the direction
of arrow 1, causing the said port gradually to cover the port al in the
valve, while the port 6 which previously had been receiving steam from the
port of the valve will now, from the same cause, gradually leave that port,
and come under the, recess of the valve, allowing the steam to escape from it

page_text: into the exhaust passage c¹, which is kept isolated from the other port by
means of the walls of the recess; upon the piston completing its stroke the
functions of the steam ports are reversed by the similar action of the cylinder.
It will be seen that the steam ports in the cylinder must be arranged so as to
form on the valve seat an angle equal to that made by the axis of the cylinder
with the centre of oscillation; this will be a variable quantity, depending upon
the length of stroke, or the distance between the centre of oscillation of
the cylinder and the axis of the crank axle, the main point being to ensure
that the exhaust port will be uncovered before the steam port is open, such lap
being given as may be thought necessary. As the steam ports on the valve
seat are at right angles with the exhaust ports, it will be apparent that by
turning the valve by means of its spindle and lever round a half circle, the
adjustment will remain perfect for the opposite exhaust passage, and the
engine will be reversed.
Having now described our Invention, and how the same acts, we wish it
understood that what we claim as new and want secured by the before in part
recited Letters Patent is, the form, arrangement, and application of the fixed
steam valve, and the form and arrangement of the ports of the steam and
exhaust passages on the seat of the valve, which, by means of the oscillation of
the cylinder over and against the face of the fixed valve, regulates the admis-
sion and the distribution of the steam, or air, or gases, as the case may be, to
the interior of the cylinder and the discharge of it, by means of the exhaust
passage.
In witness whereof, we, the said James Davis and Thomas Evans,
have hereunto set our hands and seals, this First day of January,
in the year of our Lord One thousand eight hundred and fifty-
nine.
Signed, sealed, and delivered by the above-
named James Davis and Thomas Evans in
the presence of
JAS. DAVIS.
(L.S.)
THOMAS EVANS. (L.S.)
igned, sealed, and delivered by the above-
named James Davis and Thomas Evans in
the presence of
THOMAS PENNINGTON,
JAS. DAVIS.
(L.S.)
THOMAS EVANS. (L.S.)
Parish Clerk, St. Mary's,
Ulverston.