IMPROVEMENTS IN STEAM AND OTHER ENGINES
Year: 1871

page_text: LETTERS PATENT to Joseph Ridsdale, of the Minories, in the City of
London, Engineer, for the Invention of "IMPROVEMENTS IN STEAM AND
OTHER ENGINES."
Scaled the 4th April 1871, and dated the 14th February 1871.
PROVISIONAL SPECIFICATION left by the said Joseph Ridsdale at the
Office of the Commissioners of Patents, with his Petition, on the
14th February 1871.
I, JOSEPH RIDSDALE, of the Minories, in the City of London, Engineer,
do hereby declaro the nature of the said Invention for "IMPROVEMENTS IN
STEAM AND OTHER ENGINES," to be as follows:-
This Invention relates to the construction of the cylinders of steam
and other engines and also to the arrangements of the piston rods and
cranks whereby a great economy of power is gained over the working
of those at present constructed. I propose to make the cylinders of
double the ordinary length or thereabouts so that two pistons can be
employed in them; these pistons are connected by cross heads and rods

page_text: to a crank shaft, a portion of which passes through the cylinder at or
about its centre, the joints being made steam, air, or gas tight by glands
and stuffing boxes. Both pistons are acted upon at the same time by the
power and are driven outwards to rotate the crank shaft in one direction
when a fresh supply of power is admitted on the other sides of the
pistons to establish the return stroke of them. In some cases the
cylinders may be open at both ends and the piston rods connected direct
to outer crank shafts as well as to the central crank shaft, by this
means three pairs of wheels of a locomotive, for instance, can be actuated
direct. The cylinders may be made in one or more pieces and may be
set at an angle to one another. Any number of the cylinders can be
employed side by side and their piston rods or cross heads may be caused
to operate upon cranks in any convenient manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Ridsdale in the Great Seal Patent Office
on the 14th August 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
RIDSDALE, of the Minories, in the City of London, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Joseph Ridsdale, Her special licence that I,
the said Joseph Ridsdale, my executors, administrators, and assigns, or
such others as I, the said Joseph Ridsdale, my executors, adminis-
trators, 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 AND OTHER
ENGINES," upon the condition (amongst others) that I, the said Joseph
Ridsdale, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and scals, should particularly

page_text: 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 Joseph Ridsdale, 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 :-
-
This Invention relates to the construction of steam and other engines,
and to an arrangement of the working parts, whereby a great economy
of power is gained over the working of those at present constructed, as
well as the engine being rendered more efficient. I make the cylinders
of double the ordinary_length or thereabouts so that two pistons_can_
be employed in them; these pistons are connected by cross heads and
rods to a crank or disc shaft, a portion of which passes transversely
through the cylinder at or about its centre. Both pistons are acted
upon at the same time by the power and are driven outwards to rotate
the crank shaft in one direction, when a fresh supply of power is
admitted on the other sides of the pistons to establish their return
stroke.
g
The shaft is
The Invention will be well understood by reference to the accom-
panying Drawings, in which Figure 1 shows a sectional elevation of a
cylinder a and the parts connected therewith as herein-before described.
Figure 2 is an exterior view, and Figure 3 a plan of the same engine.
The cylinder a is fitted in a horizontal manner upon a base or sole
plate b; c, c, are pistons whose rods d, d, are connected by cross heads e, e,
through the connecting rods f,f,f,f, to the crank shaft
which runs
transversely through the cylinder a as before spoken of.
supported upon bearings i, i, and it carries at its extreme ends fly or
balance wheels j, j, for equalizing the motion and for steadying the
engine when working. The cross heads e, e, are provided with slide
blocks k, k, which work in dovetail or other grooves 1, 1, in the ends
of the base plate b. The cylinder is furnished with return ports m, m, for
effecting the inward throw of the pistons, the areas of which correspond
with the areas of the central port by which the steam or other motive
agency is permitted to flow into the cylinder for producing the outward

page_text: throw, thus the action is kept up from both sides with the same amount
of force, the quantity of steam for effecting the movement being regulated
by the valve n being cut off at the proper time by the eccentric o and
rod p acting upon the tappet rod q which is pivotted at r. It will be
seen from the Drawings that the cranks on the shaft are in opposite
directions and in the position shown with the two pistons at the end
of their inward throw, consequently the next admission of steam will
force the pistons apart and produce a revolution of the crank shaft in
the same direction, the end ports being opened to the exhaust at the
same time in the usual manner. The transverse aperture through the
cylinder may be formed in various ways to prevent an escape of steam
at that part. The sides of the cylinder may be formed with stuffing
boxes, which can be packed and made steam-tight by glands, the stuffing
boxes acting as central bearers to the crank shaft or a transverse tube
may be cast with the cylinder for the shaft to pass through loosely.
Another way in which this can be accomplished is by making the
cylinder in two pieces and forming a half tube on one end of each
piece; these when bolted together will make a full cylinder of the
desired length, in which the two pistons may act in the manner herein-
before described.
I do not in all cases confine myself to the use of a crank shaft,
as it is casier and less costly to employ a straight shaft on which
discs can be fitted, the discs having pins or studs for the connecting
rods to be attached to for producing the revolutions. This will be
seen clearly by referring to Figure 4, which is a plan view of an
engine complete with discs 8, 8, on a straight shaft in lieu of cranks.
It is not necessary to connect the rods direct to the crank shaft as
before explained, as in some cases they may be attached to cranks or
pins upon toothed wheels t, t, in the manner represented in Figure 5,
which toothed wheels act upon the transverse shaft a through the
wheel u which it carries for communicating the necessary motion to the
machinery the engine is intended to drive. I have before referred to an
eccentric and rods for working the slide valve n, but these may be
dispensed with by placing a friction or gear wheel on the shaft such
as I have represented in Figures 6 and 7 to bear against or gear with
another wheel w, by which the valve can be operated to the greatest
nicety, the main object being to have as few levers and rods as possible
and to produce the various motions by rolling bodies. Any number of

page_text: the cylinders can be employed side by side and their piston rods or cross
heads may be caused to operate upon cranks or other appliances in any
convenient manner.
And 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 construction and employment of a steam or other engine
cylinder in which a shaft can pass transversely for communicating the
necessary movements to machinery, as described and shown.
Secondly. I claim the general arrangement of mechanism by which
the motion is conveyed to the transverse shaft which passes through
the cylinder, as described and shown.
And, thirdly. I claim the modifications of mechanism herein-before
referred to when employed in the manner explained.
In witness whereof, I, the said Joseph Ridsdale, have hereunto
set my hand and seal, this Fourteenth day of August, in the
year of our Lord One thousand eight hundred and seventy-
one.
Witness,
WILLIAM HENRY WALENN,
74, Brecknock Road, N.
JOSEPH RIDSDALE. (L.S.)