IMPROVEMENTS IN THE CON- STRUCTION OF ENGINES TO BE WORKED BY STEAM, AIR, OR GASES." PROVISIONAL SPECIFICATION
Year: 1861

page_text: LETTERS PATENT to James Davis, Ironmaster, Ulverston, in the County
of Lancaster, and Thomas Evans, Engine Fitter, Ulverston, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN THE CON-
STRUCTION OF ENGINES TO BE WORKED BY STEAM, AIR, OR GASES."
PROVISIONAL SPECIFICATION left by the said James Davis and Thomas
Evans at the Office of the Commissioners of Patents, with their Petition,
on the 2nd October 1861.
We, JAMES DAVIS, Ironmaster, Ulverston, in the County of Lancaster,
and THOMAS EVANS, Engine Fitter, Ulverston, in the County of Lancaster, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF ENGINES TO BE WORKED BY STEAM, AIR, OR GASES," to be as
follows, that is to say:-
Our improvements relate to the construction of engines where the admission.
of the steam is regulated by the oscillation of the cylinder; and consists in the
peculiar form and arrangement of the valve, which opens and sbuts the steam
and exhaust ports. The oscillating cylinder is mounted and rotates upon hollow
axles, through which the steam is admitted, and has the exhaust ways and
valve chest cast with it. The valve has steam ports upon it corresponding to those
of the cylinder, and a recess for covering the exhaust. The valve is held upon
its seat by the pressure of the steam on its opposite face, and is moved by
means of a spindle connected with it, and furnished at the other end with a
friction roller which works in a slot link, being varied by a lever attached,

page_text: thereto when it is desirable so to do to reverse the motion of the engine, the
said friction roller traversing the slot link with the oscillation of the engine,
gives the necessary movement to the valve without the intervention of any
eccentric or other gearing; the steam is admitted to the valve chest through a
steam pipe working in a gland and stuffing.
We also attain the same object by using a circular valve and seating, which
valve is furnished with ports, so arranged that while one is over the port
in the cylinder, the other is over the face of the seat, and is prevented
rotating by means of a spindle which passes through it and upon which it
slides, in such a way as to allow of its being continuously pressed close to the
face of its seat. The spindle of the valve passes through a small gland in the
steam pipe, which is fixed as before stated, the spindle being fitted with a
collar to prevent its being drawn out, and a lever to fix it in position. The
exhaust pipe is fitted in a similar manner to the steam pipe, hence when the
cylinder is in motion these pipes, though fixed, work freely in their junctions
with the cylinder.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Davis and Thomas Evans in the Great Seal Patent
Office on the 2nd April 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
DAVIS, Ironmaster, Ellverston, in the County of Lancaster, and THOMAS
EVANS, Engine Fitter, Ellverston, in the County of Lancaster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of October, in the year of our Lord One
thousand eight hundred and sixty-one, in the twenty-fourth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
James Davis and Thomas Evans, Her especial 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, admi-
nistrators, 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 THE CONSTRUCTION OF ENGINES TO BE
WORKED BY STEAM, AIR, OR GASES," upon the condition (amongst others) that we,
the said James Davis and Thomas Evans, our executors or administrators, by

page_text: 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 Inven-
tion, 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 :-
Our improvements relate to the construction of those engines where the
admission of the steam is regulated by the oscillation of the cylinder, and con-
sist in the peculiar form and arrangement of the valve which opens and closes
the steam and exhaust ports, and also in the peculiar mechanism by which the
motion of the valve is regulated. The cylinder is mounted and oscillates upon
hollow axles or trunnions through which the steam is admitted, and valve chest
cast with it; the valve bas steam ports upon it corresponding with those in the
cylinder, and when we use an oscillatory valve, a recess is formed for covering
the exhaust; the valve is held upon its seat by the pressure of the steam on
the
its opposite face, and is moved by means of a spindle connected with it;
other end of the spindle is fitted with a friction roller or some similar equiva-
lent, which works in a slot link fixed upon a centre, which admits of the
direction or position of the link being varied. When it is required to reverse
the motion of the engine by means of a lever attached thereto, which, by being
elevated or depressed causes the friction roller to travel on one end or the
other of the slot link, the friction roller traverses the slot link at each oscil-
lation of the cylinder, thus giving the necessary movement to the valve without
the intervention of any eccentric or other gearing.
As before mentioned, the steam is admitted to the valve chest through a
steam pipe working in a gland and stuffing box; the valve above described
resembles in shape and action the ordinary slide valve; the chief peculiarity
being that by which the reciprocatory motion of the valve is obtained.
We, instead of using, however, a valve which slides horizontally on the face
of the seating, propose to effect the same purpose by means of a fixed circular
valve placed in the valve chamber, the inner face fitting close over the steam
and exhaust ports in the side of the cylinder, the other exposed to the steam
which supplies the cylinder; the ports in this valve are so arranged that while
one port is over a corresponding port in the cylinder, the other is upon the
blank face of the seat; the valve is prevented from rotating with the cylinder
by means of a spindle which passes through it, and upon which it turns or

page_text: slides, in such a way so as to allow of its being continuously pressed close to
the face of its seat.
The end of the spindle next the valve is sometimes formed with a double
joint, in order to allow of a little play; the other end passes through a small
gland in the steam pipe; a collar fitted to it prevents it from being drawn out,
and a lever fixes it in position.
As before mentioned, the valve has ports cut on its face at regulated dis-
tances to fit the ports of the steam cylinder, and has also a sunk or hollow
portion which places the exhaust in communication with either steam port;
the steam passages are formed in the usual way, and the exhaust consists of a
passage in a belt cast partly round the cylinder.
It will be seen from this description that the valve remaining stationary
while the cylinder oscillates, one of the steam nozzles of the cylinder will
gradually come over one of the ports of the valve, and steam will be admitted
into the said passage, while the other nozzle will gradually come under the
hollow recess of the valve, and the steam from the cylinder will escape to the
exhaust; and the contrary will be the action with the return oscillation of the
cylinder; this then will be effected without any motion of the valve. In order,
however, to open the ports of the valve more quickly, so as to cut off and
admit the steam, we propose to fix a small wheel on the end of the valve
spindle; upon this wheel is fixed two studs, one on either side of its face, half
a circle apart; upon the trunnion, or on the cylinder, or any of the motive
parts is fixed a stud, from which passes a link which moves one end of a
rocking shaft; to the other end of this shaft is fixed a gab or fork which works
on the stud of the wheel on the valve spindle; the oscillation of the cylinder
causes the stud to move the rocking shaft in an opposite direction, transmitting
its motion to the gab, which in its turn acting upon the stud on the face of the
valve spindle wheel, urges the valve in a direction opposite to that of the
motion of the cylinder, and thus accelerates the opening and shutting of
the valves. If it is wished to reverse the motion of the engine by turning the
wheel half way round so as to bring the opposite stud within the arm of the
gab, the opposite ports will be brought into action, and thus the engine reversed.
Of course, it will be seen that the forks or arms of the gab regulate the
traverse or rotation of the valve, and hence retain it still as a fixed valve.
In order to render this description more clear, we have appended the accom-
panying Drawing, which are intended to illustrate the general principles of our
Invention, and also the application of the same to an engine; we at the same
time premise that different forms of engines will require modifications of the
application, and various well-known equivalents may be substituted for the

page_text: Figure I. is a side elevation, and Figure II., a plan, of an oscillating engine
with a slide valve, shewing our mode of working the same; Figure III. is a
transverse section of same, shewing the form of the valve and the mode of
actuating it.
A is the cylinder; B, the valve chest; b, the valve; 1, the valve spindle;
c, the friction roller on the valve-spindle head; d, the slot link, having the
upper head under the portion e; e' being arcs of circles, having radii equal to
the diameter between the centre of oscillation of the cylinder and the centre of
the slot, the middle portion being rectangular; f is a standard upon which the
slot link is supported, turning round the centre g, and held in its place by the
pin h, which goes through the handle R, and is fixed in the quadrant or
upright 1, which has holes placed at different heights to receive it.
Its action is as follows:-As the cylinder oscillates, say, in the direction of
the arrow, the friction roller will be urged along the rectangular portion of the
slot link, thus giving motion to the valve, which will in the usual way open
the one port and close the other; when it reaches the end of this part of the
slot, it will, during the completion of the oscillation, travel in the curved por-
tion of the slot e, during which no motion of the valve will take place; in the
return oscillation the opposite is the effect, and the motion along the rectan-
gular portion from E to E¹ causes the return motion of the slide and completes
the revolution of the crank.
When it is wished to reverse the engine, by raising the handle R the roller
is made to move in the curved portion e¹, and the reverse ports are opened and
shut to the exhaust; although the slot has been shown with a straight portion
in the centre, this is not absolutely necessary, as one could be made with a
continuous curve. The plan shown, however, has advantages; the set quad-
rant may be straight instead of curved, holes being pierced in it, on which the
handle R may be fixed at adjusted points. The other parts of the engine as
the fly wheel L, crank m, piston n, steam and exhaust pipes, need no descrip-
tion, nor does the hollow trunnion d, through which the steam obtains access
and egress to and from the cylinder.
Figure II., the dotted lines show the valve face and the ports; the dotted
red lines the nozzles of the cylinder.
The other Figures of the Drawing are intended to show the form and method
of applying our fixed disc valve.
'

page_text: Figure IV. is a vertical cross section taken transversely to the length of the
cylinder through the steam and exhaust passages, for the purpose of showing
the circular valves as applied to the face of the valve seat, together with the
valve spindle, and mode of actuating the same.
Figure V. is a horizontal section in the line of the length of the cylinder
and through the valve chest, that is, in a plane at right angles to the other,
and on the inside plane of the cylinder.
Figure VI. is a view of the cylinder, showing the valve seating and the
nozzles of the steam ports.
Figure VII. is a view of the face of the valves.
Referring to Figures 6 and 7, r, s, are the steam passages; r, s, the nozzles
of the passages; i, ¹, the exhaust ports leading to the exhaust passages in the
belt p; 2, s, (Figure 7,) are the two corresponding ports in the valve; v, the
recessed hollow which covers the exhaust and isolates it from each steam port
at the alternate strokes. Suppose now the cylinder at the end of the stroke
and about to describe an arc in the direction of the arrow (Figure 6), the
port or nozzle will now begin to take steam, which it receives through the
oscillation of the cylinder, which causes the nozzle to gradually cover the port
2 of the valve; at the same time the nozzle s', which had been previously
taking steam from s², will now, owing to the oscillation, gradually leave that
port and come under the recess of the valve, and allow the steam to escape
from it into the exhaust passage i, which is kept from the other port by the
sides of the recess; when the cylinder oscillates back again the reverse is the
action of the ports.
The steam ports on the valve seating are so arranged as to form an angle
equal to that made by the axis of the cylinder and the arc of oscillation; as
the steam ports on the seat are at right angles with the exhaust ports, it will
be seen that by turning the spindle and valve round half a circle, the functions
of the ports and motion of the engine will be reversed.
Figures VIII. and IX. show the valve in section, and steam passages and
ports; they also show the valve spindle u and its junction with the valve; it
will be seen that this spindle is jointed on two planes u, u². In the application
of the valve as above described it will be seen that the valve remains fixed, the
cylinder moving in order, however, to actuate the motion of covering and
uncovering the ports more quickly, we apply the rocking shaft arrangement
before referred; a stud h is fixed upon the trunnion of the cylinder, hence
moving with it; to this is attached the lever h¹, which actuates through a link
the rocking shaft h³, and in its turn gives motion to the gab h³, which working
on a stud h in the wheel i, fixed to the valve spindle, causes it to move in a

page_text: direction opposite to that of the moving cylinder, and thus accellerates the
opening and shutting of the ports.
Having now described the nature of our Invention, and how the same
is formed, combined, and acts, we wish it understood that what we claim and
wish secured by the before in part recited Letters Patent is,-
First, the plan of actuating slide valves of oscillating cylindrical engines,
similar in principle to those shown in Figures 1, 2, and 3, by the means and in
the manner generally as set forth in the said Figures, and more particularly
described in the accompanying Specification.
Second, we claim the method, means, and arrangement of actuating a fixed
circular valve, formed and constructed similar to that shown in Figures 4, 5,
6, and 7 of the Drawings, and more particularly herein described, when these
valves are applied to oscillatory engines having the arrangement and disposition
of therein shown, more particularly the arrangement of the valve seating and
steam and exhaust passages, substantially as shown in the Drawings, and more
particularly described in the accompanying Specification.
Third, the arrangement and combination of parts for actuating, by means of
a rocking shaft or its equivalent, a wheel or its equivalent fixed on the end of
the valve spindle, for the purpose of accelerating the action of the said circular
fixed valve, substantially as described herein and generally illustrated in
Figures 6 and 7 of the appended Drawings.
In witness whereof, I, the said James Davis, for myself and on the behalf
of the said Thomas Evans, have hereunto set my hand and seal, this
Second day of April, One thousand eight hundred and sixty-two.
JAMES DAVIS. (L.S.)