A NEW ROTARY STEAM ENGINE
Year: 1853

page_text: LETTERS PATENT to François George Sicardo, of Marseilles,
France, and of 4, South Street, 'Finsbury, London, Gentleman,
for the Invention of "A NEW ROTARY STEAM ENGINE."
PROVISIONAL SPECIFICATION. left by the said François-George
Sicardo at the Office of the Commissioners of Patents, with bis
Petition, on the 19th-April 1853.
I, FRANÇOIS GEORGE SICARDO, of Marseilles (France), and of 4, South
Street, Finsbury, London, Gentleman, do hereby declare that the nature
of the Invention for "A NEW ROTARY STEAM ENGINE" to be as
follows:-
The Invention consists in the combination of certain mechanical
organs for the construction of a new rotary steam engine.
DESCRIPTION OF THE DRAWINGS.
Figure 1, is a front view of the engine, showing its external casing.
Figure 2, is an end view, showing the internal channeling A', B'.
Figure 3, is a vertical section of Figure 1, showing the internal
construction.

page_text: A, B, Figure 1, foundation on which the machinery rests. C, D, E, E,
box or case containing the machinery (Figures 2, and 3).. G, II, I, K,
Figure 3, cylinder. L, M, Fig. 2, horizontal-shaft: -N, O, Fig: 2,
upright supports. a, b, Fig. 2, stuffing boxes.
The box C, D, E, F, Fig. 3, is provided with a channel A', B',
Fig. 2, running from M, N, Fig. 3, serving to annul the force of the
steam, which only acts with effect on the pistons between the spaces
M, M, and N, N, Fig. 3. h, i, Fig. 3, is the valve for the introduction
and interception of steam. a, b, a, b, &c., are the paddles or pistons,
k, l, m, n, Fig. 3, tube for the introduction and escape of the steam.
The outer casing of the machine is provided with the ribs a', b', &c.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said François George Sicardo, in the Great Seal Patent
Office, on the 18th October 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
FRANÇOIS GEORGE SICARDO, of Marseilles, France, and of 4, South
Street, Finsbury, London, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of April, in the year
of our Lord One thousand eight hundred and fifty-three, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said François George Sicardo, Her special
licence that I, the said François George Ricardo, my executors, admi-
nistrators, and assigns, or such others as I, the said François George
Sicardo, 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
"A NEW ROTARY STEAM ENGINE," upon the condition (amongst others)
that I, the said François George Sicardo, by an instrument in writing

page_text: under my hand and seal, should particularly describe and ascertain the
nature of the said Iuvention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Scal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said François George Sicardo, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, reference being had
to the drawings hereunto annexed, and to the figures and letters
marked thereon, that is to say:
The Invention consists in a new combination of mechanical parts for
the construction of a rotatory engine in which the defects hitherto
experienced are obviated. The machine is here supposed to be applied
to a steam boat.
Figure 1, is a front view of the engine. Figure 2, a side view.
Figure 3, is a vertical section of the same through the cylinder and
steam box, at right angles to the shaft L, M. Figure 4, is another
vertical section of the engine parallel to the shaft L, M. Figure 5,
is a section of the steam box across the shaft. Figure 6, is a cor-
responding section of the cylinder. The other Figures are views of
separate parts.
DESCRIPTION OF THE DRAWINGS.
A, B, Figures 1, 2, 3, and 4, foundation plate of cast iron, iron, or
other solid metal, the dimensions of which vary according to the i-
mension and application of the engine. C, D, E, F, Figure 3, metallic
box, having its diameter through the centre L, allowance being made
for the angle of the paddles. The width of the box C, D, Figures 2,
and 5, varies. The nuts c, c', D, D', Figure 2, serve to hold the bolts
b, b, b, b, b, b, which fasten the covers G, K, and E, I, to the box.
The box has, from M, to N, Figure 3, a canal, as seen in A, B, Figure
5, and of which the external part is seen in A', B', Figure 2. This
canal serves to receive the steam and propel the paddles from M, to N,
Figure 3, for going forward, or from N, to M, for going backwards.

page_text: This canal is closed when the paddles are traversing this space; and
all escape of steam being intercepted, the paddles from N, to M,
receive all its power, and thus produce- in their course their full effect.
The box is provided with a packing piece h, i, Figures 3, and 4, seen
in front and back views, Figures 7, and 8, provided with springs
A, B, C, D, Figure 7. The blade spring A, B, pushes the packing
piece forward against the point h, Figure 3, to intercept the passage of
the steam at the point of its introduction. The spring C, D, Figure 7,
serves to press the packing piece against the cylinder, to intercept the
passage of the steam between the cylinder and the box. This packing
or stuffing piece is also provided with a brass plate A, B, C, D, Figure
8, which rubs against the cylinder, and is so placed as to be easily
removed when worn out. Instead of placing the spring C, D, inter-
nally, as represented in Figure 7, it may be set externally, as seen in
Figure 2, and the plate will be pressed by the screws V, V, kept tight
by means of the nuts e', e', e', e'. The mouth of the pipe k, l, m, n,
Figure 3, serves for the introduction and egress of the steam, and is
connected with the conduct pipes.
The casing plates are furnished with the nerves a, b, a', b', a, b,
a', b', the number and dimensions of which vary according to the size
of the engine, and the pressure to which it is to be subjected..
A circle m', n', o', Figure 1, or m', n', Figure 2, may be added, if
necessary. These plates or covers have in c', d', brass rings, which
serve as bearings to the horizontal shaft c', d', 'c', d', Figure 4. They
also contain. the stuffing boxes;. Figure 4, f', c', and d, g, which are
likewise furnished with brass rings, and aid to support the said shaft.
There are between the bearings and those of the chairs, hereafter
described, a length of bearing sufficient to resist, during a long time,
the wear produced by the rotation of the horizontal shaft.
The cylinder G, H, I, K, Figure 3, has six grooves a, b, Figure 3,
in which slide six paddles, hereafter described. Its diameter, must be
large enough to allow the largest possible developement of the paddles
between the two extremities of the lower part of the canal. The steam
paddles slide in them, and the length a, b, can contain the whole paddle,
so that when the cylinder rulis against the packing piece h, i, the

page_text: paddle inay in no manner impede the rotation of the cylinder. The
cylinder has on either side a circular groove c, c, c, c, c, c, Figure 3,
represented in A, B, C, D, Figure 6. On both sides of the grooves of
the paddles there is also a space 4, 5, and 6, Figure 3. There is also
in this cylinder, on each side of every paddle, a groove e, f, Figure 3,
having brass plates fixed in them to bear the friction of the paddles'
and avoid their contact with the metal of the cylinder. For engines
of more than ten horse power, spaces are made through the whole
length of the cylinder, as in m, m, m, m, to reduce its weight. The
horizontal shaft L, (Figures 1, and 3,) L, M, (Figures 2, and 4,) is of
a diameter proportioned to the power of the engine; care must be taken
to give the part which enters the cylinder, as in e, f, Figure 4, a little
larger diameter, in order to fix in it the keys to make it fast on the
cylinder, so that they may be driven easily in or out. The length of
the shaft will depend on the place which the engine is to occupy; it
has six holes 9, 9, g, bored through, which will be hereafter explained.
The chairs or supports of the shaft, seen in N, O, P, Figure 1, or N, O,
Figures (2, and 4,) are furnished with brass bearings h, i, Figure 4.
and are fixed to the foundation plate A, B, by bolts, as seen in N, P,
Figure 1. a, b, Figure 2, are stuffing boxes, fastened to a flange of the
covers by the nuts e, e, e, e, of the screw bolts. These stuffing boxes are
furnished, in f, c, d, g, Figure 4, with a brass or other suitable ring,
which aids to support the horizontal shaft, and lessen the pressure on
the ring of the cover, and on the bearings of the chairs. The six steam
paddles slide in the grooves a, b, a, b, a, b, Figure 3, the thickness of
which is seen in G, H, and the total surface in E, F, G, H, Figure 4;
they may be made either of steel, iron, cast iron, or any other metal,
thick enough to resist the pressure of steam without bending. These
paddles must have, beside the acting projection I, I', Figure 3, a part
which remains in the groove when the paddle is extended; and this
part is made to lean against the cylinder in K", so that the brass
packings over which it slides may not be in contact. In E, and F,
Figure 4, there are two small lugs or bits, made to support the paddle
at the point K". When the paddles have entered the grooves, these
lugs are made to enter the cavities E', F1, Figure 4, in the nave of the

page_text: revolving cylinder, as seen in a, a, Figure 3. The paddles are com-
posed of two or three plates, in order to leave space between the two
external surfaces capable of receiving the packings 1, 2, 2,3, and 3, 4,
Figure 4, with the springs adapted to the same, and indicated by the
numbers 9, and 10, of the same Figure. They may be also made of
one piece, leaving the same cavities for the packings and springs.
These paddles are provided also with packings and springs. The steam!
box C, D, E, F, Figure 3, is provided in its internal circumference
with brass friction packings M, M, N, N, the top and bottom of which
is seen in h, i, and F, G, Figure 4. They are applied to the box so as
not to allow any escape of steam from M, to M, or from N, to N,
Figure 3. They may be fastened to the box by rivets. These packings
are divided into four parts, one from M, to M, one from N, to N, and
the other two from M, to N, Figure 3. The parts from M, to N, are
each formed of two pieces, to allow space for a canal. Instead of
fixing them to the box by rivets, they may be dovetailed, as in Figure 9.
In this case, the steam box C, D, E, F, Figure 3, is to be made of four
corresponding parts. These four parts meet on all sides, and form the
canal M, N, of the same Figure. By dividing the steam box in this
manner, and then fastening the four parts together with bolts, it will be
easy to introduce and fix the packing pieces, which correspond with
each part, and may be secured without the aid of rivets. It will suffice
in this case, to avoid any escape of steam, to put a little minium, white
lead, or any similar matter, under the packings M, M, and N, N. In
all cases the several parts of the packings must be a little shorter than
necessary, and a little space must be left between each of them, on ac-
count of the dilatation which results from the action of caloric, in order
that they may not cause an impediment to the passage of the paddles:
The cylinder G, H, I, K, Figure 3, is provided with the circle c, c, c, c, c,
which is intersected at every paddle; the circle touches the parts
G, H, I, K, which parts pass close to the sides of the covers. Intervals
must be left in the interior G, H, I", K", between the parts of the
circle and the cylinder, which intervals may be filled up in proportion
as the packing wears out; for this reason, the holes for the fastening
bolts c, c, c, c, Figure 3, have an oval shape, so that when the packing,

page_text: as it wears out, approaches the centre L, it is not impeded by the bolts
c, c. This packing is placed on each side of the cylinder.
Between the two sets of packings c, c, other packings 3, 3, 3, 3,
Figure 3, are placed. They are represented in Figure 10, where the
piece A, B, represents one of the parts of the circle c, c, c, c, Figure 3.
A', B', and A", B", are side views of the same piece. They are com-
bined with the packings C', D', Figure 10. The extremities of these
sets of packing pieces form an angle of forty to forty-five degrees, as
seen in C, D, or C, D, Figure 10. These angles, meeting with the
angles of the packings A, B, or A', B', form together a right angle.
The packing pieces have a spring E, F, which, bearing on the part
G, H, I, K, Figure 3, tends to force the parts 3, 3, 3, towards the centre
L, Figure 3, on account of the inclination m, n, Figure 10. The
spring tends to press the parts of the circle c, c, c, c, Figure 3, against
the covers G, K, or H, I, Figure 2; whilst the other inclination a, a,
Figure 10, tends to force the part 3, 3, 3, Figure 3, against the pad-
dles; thus the steam is prevented from passing between the paddles
and packings, or the packings and covers. The parts 4, 5, 6, Figure 3,
A, B, and C, D, Figure 6, are filled with cotton enveloped in canvas
or vulcanised caoutchouc. The cylinder is also furnished with brass
packing pieces G", G, H", H, Figure 3, fixed in the parts E, F,
and G, H, Figure 6, which consist of plates of a sufficient thickness to
avoid the friction between the surfaces of the paddles, and the cylinder.
If the paddles are made of cast iron, the packings may be made of
the same metal.
Instead of the inclined sections m, n, and x, x, of the piece C, D,
Figure 10, for joining the four pieces which form together a sector, C', D',
A", A, B, B, C, D', same Figure, this junction may be made as seen
in Figure 12, where the joining ends A, A, of the piece C, D, press
the corresponding ends B, B, of the right side packing, one of which is
represented by E, F. The packing piece C, D, is divided into two
pieces in a, and between these two pieces there is an angular piece
or wedge b, in which the screw b, c, enters, and passing through a hole
in a¹, Figure 3, is fitted with two nuts, which hold the spring a, B.

page_text: This spring forces the wedge i between the two pieces forming the
packing C, D, Figure 12, and by this means the lateral wear and tear
will be compensated. For preventing the space formed between the
two pieces from being a cause of waste of steam, a small piece e, f, is
introduced between them; this piece is seen in both views C, D, and
G, H, of the packing piece. This piece being well adjusted, the steam
cannot enter the cylinder. In order to have the two parts of the
packing C, D, bearing exactly against the covers of the engine, there is
an iron plate I, K, placed under G, H, Figure 12, and this plate is
forced against the packing by the spring l, m, which bears against the
cylinder in the groove A, or B, Figure 6. The grooves in the paddles,
as before stated, contain the packing pieces 1,2, 2, 3, and 3, 4, Figure
4. The packing 2, 3, is fixed to the paddles by rivets, as is seen in
Figure 4; a spring 5, 6, in each paddle is set opposite this packing, and
the connecting rods 5, 7, 6, 8, bear against the opposite springs. These
connecting rods serve to connect two opposite paddles; they traverse the
horizontal shaft through the holes g, g, so that the extremities of the
paddles inay always touch in every direction the friction packings
M, M, N, N, of the steam box, Figure 3. The springs 5, 6, Figure 4,
serve to compensate for the wear of the packings. The power of the
springs must be equal to the pressure of the steam at the end of a
paddle.
The packings can be made to pivot, as represented in Figure 13.
a, a, is a steel or wrought iron rod, and b, b, is made of brass or cast
iron, and is fixed to a, a, by screws, or rivetted to it. The rod is
pierced longitudinally at its two extremities with a hole, the diameter
of which is large enough to lodge a spiral spring, serving to push the
catch T, against the lids. When this packing is employed, I use the
canal A, B, instead of the canals A', A', 22, 22, 33, 33, Figure 5.
The packings 1, 2, and 3, 4, Figure 4, form a parallelogram, and have
internally springs 9, 10, which tend to force them against the covers.
The side which touches the cover is furnished with a thin brass plate, in
order to lessen the friction; this plate is fixed with rivets, and may be
easily changed when it is worn out. The lateral packing of the paddles

page_text: may
be of cast iron; and instead of the form of a parallelogram, as in
Figures 1, and 2, it may be rectangular, as seen in Figure 11...
This engine being applied to propel a boat, to have it moving forward,
the steam is introduced into the steam box, through the ingress pipe W;
and the canal M, N, affording a free passage to it, the steam enters the
spaces A, B, at both sides of the paddle when in a horizontal posi-
tion; the paddle being pressed alike above and underneath by the steam
arriving on both sides at the same time, is not set directly in motion;
but when the paddle, by the motion of the shaft, is arrived in N, the
canal not being open from N to I', it stops entirely the passage of the
steam, which then pushes it forward as far as I¹. As soon as it is a
little beyond I, the paddle then being over the canal N, M, at.the
opposite side or egress of the box, the steam rushes through the passage
into the canal, and egresses by the pipe Y. If any steam be left be-
hind, between Y, and M, on the egress side, it will escape through the
upper portion of the canal; and the paddle playing in the space N, M,
at the egress side, will not be affected by the pressure of the steam.
The steam arriving through the ingress pipe W, will press on all the
confining partitions, and meeting the paddle when beyond the canal,
it will drive it forward, and thus cause the rotative motion of the engine,
which motion will continue uniformly. When it is necessary to give
a backward motion to the boat, the steam is let in through the pipe Y,
and acts on the paddles in a similar manner to that before stated; it
escapes through the pipe W.
For letting the steam enter the engine by either of the inlets W, or
Y, any of the means in general use may be employed; the simplest and
most convenient being to have the steam traversing a cast iron steam
chest, fitted with a sliding valve, as is customary in common piston
steam engines. This steam chest is placed between the boiler's outlet
and the engine.
Having now described the nature of my said Invention, and the
manner of carrying the same into effect, I wish it to be understood that
I do not confine myself to the precise details herein laid down, nor do I
claim the different mechanical organs herein described, taken separately;

page_text: but what I do claim as my Invention is, the new combination of mecha-
nical organs for constructing a rotary steam engine, as herein-before
described and referred to in the various figures of the drawings.
In witness whereof, I, the said François George Sicardo, have
hereunto set my hand and seal, this Eleventh day of October,
One thousand eight hundred and fifty-three.
FRANÇOIS GGES SICARDO.
(L.S.)
Witness,
A. H. PATTISON.