A NEW AUXILIARY SCREW PROPELLING APPARATUS TO BE APPLIED TO FISHING CRAFT OR OTHER SAILING VESSELS
Year: 1873

page_text: LETTERS PATENT to Thomas Smithdale, of Saint Ann's Iron Works,
King Street, in the City of Norwich, Engineer, for the Invention
of "A NEW AUXILIARY SCREW PROPELLING APPARATUS TO BE APPLIED TO
FISHING CRAFT OR OTHER SAILING VESSELS."
"
Sealed the 20th April 1873, and dated the 10th March 1873.
PROVISIONAL SPECIFICATION left by the said Thomas Smithdale at
the Office of the Commissioners of Patents, with his Petition, on
the 10th March 1878.
I, THOMAS SMITHDALE, of Saint Ann's Iron Works, King Street, in
5 the City of Norwich, Engineer, do hereby declare the nature of the said
Invention of "A NEW AUXILIARY SCREW PROPELLING APPARATUS TO BE APPLIED
TO FISHING CRAFT OR OTHER SAILING VESSELS," to be as follows:—
This Invention has for its object the construction and application to
sailing vessels, and particularly to fishing craft, of an auxiliary screw
O apparatus to be used occasionally, and in which the scrow when not in
use is not raised out of its place as has been the caso in all auxiliary
screw propelling arrangements, and consists of constructing the stern

page_text: post of sailing vessels, so as that the said stern post may receive within
it in a screw propeller, and also be provided with shutters for the purpose
of enclosing the same screw, thereby protecting it from being fouled
with ropes, nets, &c., or from being an impediment to the sailing
qualities of the vessel. The shutters are to be so constructed and
applied to the stern post as to open and shut, either by sliding vertically
or horizontally in the said stern post or otherwise; when required to open
vertically, the shutters are provided with a segment of a nut and a screw
working into the same, the screw to be turned by means of worm, bevil,
or spur wheels upon the deck of vessel; when these wheels are turned
the screw will revolve and raise the shutters sufficiently to give a proper
opening for the screw propeller to work freely, and when it is required
to close the shutters the wheels upon the deck only require to be turned
the reverse way. In order to know when the screw propeller stands in
a vertical position the crank shaft of engine is provided with an index ]
plate for that purpose.
.
When it is required to shut or open the shutters horizontally they are
provided with rods passing through stuffing boxes in the stern of the
vessel; these rods are attached to a screw or nut and a hand wheel or
crank inside the vessel. When the hand wheel or crank is turned in one 2
direction the screw or nut will pull the shutters open and the reverse
will shut them. This same screw or nut is also attached to a clutch
sliding upon the screw propeller shaft, and is actuated by the same
motion for the purpose of connecting and disconnecting the screw
propeller shaft from the crank shaft of steam engine or other motive- 2
power for driving same. By this arrangement it will be impossible to
put the propeller in motion until the shutters are open sufficiently wide
to allow of its turning freely in the open of the stern post, and thereby
preventing any chances of breakage or putting the apparatus out of
order.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of March in the year
of our Lord One thousand eight hundred and seventy-three, in tho
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
3 give and grant unto me, the said Thomas Smithdale, Her special licence
that I, tho said Thomas Smithdale, my executors, administrators, and
assigns, or such others as I, the said Thomas Smithdale, 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 AUXILIARY SCREW
PROPELLING APPARATUS TO BE APPLIED TO FISHING CRAFT OR OTHER SAILING
VESSELS," upon the condition (amongst others) that I, the said Thomas
3 Smithdale, my exccutors or administrators, by an instrument in writing
under my, or their, or one of their hands and scals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to bo performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the dato of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Smithdale, do hereby declaro
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 tho
following statement, that is to say:-
My Invention has for its object the construction and application to
sailing vessels, and particularly to fishing craft, of an auxiliary screw
apparatus to be used occasionally, and in which the screw when not in
use is not raised out of its place as has been the case in all auxiliary.
screw propelling arrangements, and consists of constructing the stern
post of sailing vessels, so as that the said stern post may receive within it
a screw propeller, and also be provided with shutters for the purpose of
enclosing the same screw, thereby protecting it from being foulded with
ropes, nots, &c., or from being an impediment to the sailing qualities of
the vessel. The shutters are to be so constructed and applied to tho
stern post as to open and shut either by sliding vertically or horizontally
in the same stern post or otherwiso; when required to open vertically the
shutters are provided with a segment of a nut and a screw working into
the same, the screw to be turned by means of worm, bevil, or spur wheels
14

page_text: upon the deck of vessel; when these wheels are turned the screw will
revolve and raise the shutters sufficiently to give a proper opening for
the screw propeller to work freely, and when it is required to close the
shutters the wheels upon the deck only require to be turned the reverse
way. In order to know when the screw propeller stands in a vertical |
position the crank shaft of engine is provided with an index plato for
that purpose.
When it is required to shut or open the shutters horizontally they are
provided with rods passing through stuffing boxes in the stern of the
vessel; these rods are attached to a screw or nut and a hand wheel or
crank inside the vessel. When the hand wheel or crank is turned in one
direction the screw or nut will pull the shutters open and the reverse
will shut them. This same screw or nut is also attached to a clutch
sliding upon the screw propeller shaft, and is actuated by the same
motion for the purpose of connecting and disconnecting the screw
propeller shaft from the crank shaft of steam engine or other motive power
for driving same. By this arrangement it will be impossible to put the
propeller in motion until the shutters are open sufficiently wide to allow
of its turning freely in the open of the stern post, and thereby preventing
any chances of breakage or putting the apparatus out of order.
The manner in which I carry my Invention into effect is shewn in the
accompanying Drawings.
Figure 1 is a side view of storn of vessel; Figure-2 is an end view;
Figure 3 is a longitudinal section; Figure 4 a sectional plane, and
Figure 5 side and end clevation of supplementary metal stern post.
Upon the stern post and dead wood of vessel I attach a supplementary
stern post of iron or other metal A, A, Figures 1 and 2. This
supplementary stern post is provided with shutters B, B, shewn in
Figures 1, 2, 4, and 5, sliding in horizontal rabbets O, O, also shewn on
Figure 5. These shutters are attached to two rods A, A, Figures 4
and 5, passing through stuffing boxes B, B, Figures 3 and 4, also
attached to a rack and pinion C, D, Figure 3, actuated by hand wheel E,
Figure 3. The rack C is also attached to two levers, Figure 3, which are
provided with two pins, and runners or blocks working in groove of
clutch G, Figures 3 and 4; by this arrangement the clutch is thrown into
gear with a corresponding clutch H, Figure 8, on the driving shaft of
motive power, and at the same time open the shutters B, B, Figuros 1,

page_text: 2, 4, and 5, sufficiently to allow the screw propeller H, Figures 2, 8,
and 4, when it is required to stop the propeller or use the driving shaft
for any other purpose (such as driving as capstan), the clutch G is pulled
out of gear by means of the rack and pinion before-mentioned, and at
the same time close the shutters B, as shewn in Figure 1, and thereby
present a smooth surface to action of the water when tho vessel is
sailing, and at the same time perfectly protecting the screw propeller.
Or the shutters and clutch may be actuated by scrow and nut instead of
the rack.
My Invention further consists in opening or closing the shutters in a
vertical position, as described by Figures 6, 7, 8, 9, and 10; Figure 6 is
an end view of stern of vessol part cut away for the purpose of showing
shutters; Figure 7 is a longitudinal section; Figure 8 is sido and end
clevation of stern post; Figure 9 a sectional plan, and Figure 10 a plan
of motion on deck of vessel. I attach a metal stern post Z, Z, and
(similar construction as before described) to the existing stern post and
dead wood of vessel; this stern post is provided with shutters Y, Y,
Figures 6, 8, and 9, working in rabbets X, X, Figures 8 and 9. The
shutters are attached to nuts W, W, Figures 6 and 8, through which
pass two long metal screws V, V, Figures 6 and 8; on the top of these
screws are worm wheels T, T, which are actuated by the worm and hand
wheel 8, 8, Figures 6, 7, and 10. By this arrangement the shutters can
be raised or lowered at pleasure.
Either of the arrangements just described can be attached to wood or
iron vessels, or a new vessel of wood or iron can bo so constructed as to
receive shutters.
To witness shoe T the mid Thaman Smithdele bows howtofnun