IMPROVEMENTS IN THE CON- STRUCTION OF SIDE PROPELLERS FOR NAVIGABLE VESSELS
Year: 1866

page_text: LETTERS PATENT to Edward Forster, of Birkenhead, in the County of
Chester, Engineer, for the Invention of "IMPROVEMENTS IN THE CON-
STRUCTION OF SIDE PROPELLERS FOR NAVIGABLE VESSELS."
Sealed the 4th September 1866, and dated the 9th March 1866.
PROVISIONAL SPECIFICATION left by the said Edward Forster at the
Office of the Commissioners of Patents, with bis Petition, on the 9th
March 1866.
I, EDWARD FORSTER, of Birkenhead, in the County of Chester, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF SIDE PROPELLERS FOR NAVIGABLE VESSELS," to be as follows:-
My Invention relates to the construction of that class of side propellers in
which the floats are caused to move or feather on axes parallel or nearly
parallel to the line of the driving shaft, and the propelling surfaces thereof aro
kept in a vertical or nearly vertical position both when in and out of the
water.
I attach paddle-wheel framework or radial arms of any ordinary or suitable
description to the propelling shaft. At equal distances from the said pro-

page_text: pelling shaft, and preferably at equal distances from each other, I support
the axes or shafts of the floats in metal or other bearings. To one of the ends
of each of these axes or shafts I attach a crank or its equivalent for the
purpose herein-after specified. Between the said framework or radial arms,
and the side of the ship I place an excentric wheel or picco with spokes, near
the periphery or ends of tho arms of which there is an opening or connection
to receive a pin or piece from the cranks or their equivalents attached as
above described to the axes or shafts of the floats. The centro part of the.
excentric wheel or piece with spokes, which acts as a balance weight in the
best position, that is, close to the shaft, surrounds the driving shaft; it rests
in or on an excentric guide supported in or connected to the sido of the ship
in grooves or otherwise. Set screws to move the said excentric guide and
allow for wear are provided. When the driving shaft is in motion it will be
obvious that both wheels must be carried round, and that the one being
excentric, in distance equal to the length of the cranks, the floats will be
caused to assume the vertical position first above mentioned, and that each
crank will be at the extreme point when the excentric arm which carries it is
at that point of the excentric guide farthest from the driving shaft, and
vice versa.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Forster in the Great Seal Patent Office on the
8th September 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
FORSTER, of Birkenhead, in the County of Chester, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of March, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said. Edward Forster, Her special license that I, the said Edward
Forster, my executors, administrators, and assigns, or such others as I, the
said Edward Forster, 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 "IMPROVE..

page_text: MENTS IN THE CONSTRUCTION OF SIDE PROPELLERS FOR NAVIGABLE VESSELS," upon
the condition (amongst others) that I, the said Edward Forster, 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 per-
formed, 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 Edward Forster, 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,
(that is to say)
:-
My Invention relates to the construction of that class of side propellers
in which the floats are caused to move or feather on axes parallel or nearly
parallel to the line of the driving shaft, and the propelling surfaces thereof,
that is, of the floats, are kept in a vertical or nearly vertical position both
when in and out of the water.
I attach paddle-wheel framework or radial arms of any ordinary or suitable
description to the propelling shaft. At equal distances from the said pro-
pelling shaft, and preferably at equal distances from each other, I support the
axes or shafts of the floats in metal or other bearings formed in the paddle-
wheel framework or radial arms. To one of the ends of each of these axes or
shafts I attach a crank or its equivalent for the purpose herein-after specified..
Between the said framework or radial arms and the side of the ship I place
an excentric wheel or piece with spokes, near the periphery or ends of the
arms of which there is an opening or connection to receive a pin or piece
from each of the cranks or their equivalents attached as above described to the
axes or shafts of the floats. The centre part of the excentric wheel or piece
with spokes, which acts as a balance weight in the best position, that is, close
to the shaft, surrounds the driving shaft; it rests in or on an excentric guide
supported in or connected to the side of the ship in grooves or otherwise. Set
screws to move the said excentric guide and allow for wear are provided.
When the driving shaft is in motion it will be obvious that both wheels must
be carried round, and that the one being excentric, in distance equal to the
length of the cranks, the floats will be caused to assume the vertical position
first above mentioned, and that each crank will be at the extreme extension
when the excentric arm which carries it is at that point of the excentric guide
farthest from the driving shaft, and vico versa.

page_text: That my improvements may be clearly understood I have attached hereto
a Sheet of illustrative Drawings.
Fig. 1 represent a side elevation of the inner side of a propeller constructed
according to my Invention, in which the excentric wheel is placed between the
fixed paddle-wheel framework or radial arms and the side of the ship; Fig. 2
is an edge or end elevation, and Fig. 3 a transverse vertical section, both of
the propeller shewn by Fig. 1; Fig. 4 is a side elevation, and Fig. 5 a hori-
zontal section of another modification of means for adjusting the excentrio
guide.
In Figs. 1, 2, and 3 like letters denote the same parts. a is the side of a
ship; b, the propelling shaft, carried in bearings in the ordinary manner;
c, paddle wheel or framework fixed on b; d, axes or shafts resting in c, and
carrying the feathering floats e. On the inner ends of d steadfast cranks fare
formed 139, the excentric wheel or radial arms into which the pins h of the
cranks are connected. Part of the centre or boss of g fits into and works in
the excentric guide piece i; the latter is connected to the sido of the ship by
the grooved connecting pieces j, and is steadied by the set screws k. When i
is made heavy enough to act as a balance weight these screws simply act as
guides; but, as here shewn, i is constructed in two pieces and is held rigidly,
by k and the supporting bolts 1, the nuts of which latter are secured outside
the bridge piece m. The connecting pieces are shown without a bottom or
lower bearing for i, and they are secured to the ship's side by bolts n, but it
will be obvious they might be constructed in or as part of the ship's side.
In Figs. 4 and 5 denotes the side of the ship; p, the excentric guide
resting in the grooved piece q; r, pieces for fastening 9 to o when g is not
formed in or as part of the ship; s, the excentric constructed to work in a
grove in Pi t are pinching screws, both at the sides and bottom, for securing,
moving, and adjusting p and s when worn.
It will be obvious that the excentric wheel, and the parts connected thereto,
may be placed outside the floats near the outer bearings for the shaft; but I
would here state that by the arrangements and details herein described, both
when the excentric guide is left to slide freely and acts as a balance weight and
when fixed, as shewn on the Drawings, that the floats will always be kept in
position to take unbroken water properly either when moving ahead or astern,
and when driven fast and slow, and that suitable provision is made to allow
for wear and tear, and for these reasons I prefer the arrangements, or sub-
stantially the arrangements, shewn by the Drawings.
Having now described the nature and particularized my said Invention by
;

page_text: two modifications, I would have it understood that what I claim is, con-
structing and combining the parts forming the side propellers for navigable
vessels, substantially as herein described and as illustrated by the Drawings.
In witness whereof, I, the said Edward Forster, have hereunto set my
hand and seal, this Sixth day of September, in the year of our Lord
One thousand eight hundred and sixty-six.
In the presence of
JOHN T, KING,
Patent Agent,
Liverpool,
EDWARD FORSTER. (L.B.)