Improvements in Screw Vessels.
Year: 1892

page_text: Date of Application, 12th Feb., 1892
Complete Specification Left, 18th Oct., 1892-Accepted, 19th Nov., 1892
PROVISIONAL SPECIFICATION.
Improvements in Screw Vessels.
I PAUL ORIOLLE of Nantes (Loire Inférieure) France, Engineer, do hereby
declare the nature of this invention to be as follows:-
My invention relates to a screw propeller working in a cavity or tunnel in the
bottom of the hull about amidships, and it has for its object to avoid the liability
of injury to the walls of the tunnel by a floating object drawn into the tunnel by
the suction of the propeller.
According to this invention
(1) I make the curved walls of the tunnel or tunnels in which the screw or
screws are placed continuous like the lines of a fine built vessel, and without any
interruption especially at the part near the screw.
(2) In order to facilitate access to the propeller for repairs or renewal from
the interior of the ship while afloat, I construct a watertight well which encloses
that part of the tunnel in which the screw is placed and extends from the bottom
to the deck and into which air may be forced so as to convert it into an air-lock
chamber in which to work. The bottom of the well is separated from the tunnel
by means of a door forming part of the crown of the tunnel in order to avoid the
loss of power due to the whirling motion of the water thrown up by the screw
in the well were the crown of the tunnel open thereto, this being an essential
feature of the invention.
(3) The propeller although much better protected than when placed at the
stern is yet liable to damage from contact with floating objects, the consequent
danger being greater than with an external screw since not only the propeller
but the walls of the tunnel which forms a portion of the hull may be injured and
so cause the vessel to founder were it not for the protection afforded by
surrounding the tunnel at this point by a watertight well. This well should be
connected to the bottom of the vessel at each side of this part of the tunnel and
also to the tunnel itself both in front and rear of so as to wholly enclose the
part of the tunnel liable to injury. Where this is not practicable, the sides of the
tunnel may be extended upwards to form the well, a grating of iron bars being
provided in the tunnel to prevent the admission to the tunnel of any floating object
of sufficient bulk to damage the propeller.
.
In the accompanying drawings Figure 1 represents a longitudinal section,
Figure 2 a cross section, and Figure a plan of a vessel having twin internal
screws. Figure 4 is a longitudinal section on a larger scale of the tunnel and well,
Figure 5 is a plan, and Figure 6 a cross section on line A-B of the same.
The same letters of reference indicate the same parts in all the figures. Fis
the cover closing the aperture in the crown of the tunnel E secured by rods C.
DD are gratings in the tunnel for protecting the propeller. H H are the side
walls of the well making a watertight joint with the bottom of the hull, and K the
transverse walls making a watertight joint with the bottom and with the tunnel I
to enclose the latter, as shown in Figure 6. L quarters for crew.
MM ship's holds. N cabins. O engines. P boilers. R coal bunkers. TT screws,
each placed in a tunnel and well, as described.
SO 88
Dated this 12th day of February 1892.

page_text: Improvements in Screw Vessels.
1 PAUL ORIOLLE of 86 Quai de la Fosse, Nantes (Loire Inférieure) France
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :---
My invention relates to vessels propelled by screws working in a cavity or 5
tunnel formed in the bottom of the hull amidships, and it has for its object to
avoid the liability of injury to the walls of the tunnel by a floating object drawn
into the tunnel by the suction of the propeller.
According to this invention I make the curved walls of the tunnel or tunnels in
which the screw or screws are placed continuous like the lines of a fine built 1
vessel, and without any interruption especially at the part near the screw.
In order to facilitate access to the propeller for repairs or renewal from the
interior of the ship while the vessel is afloat, I construct a watertight well which
encloses that part of the tunnel in which the screw is placed and extends from the
bottom of the hull to the main deck and into which air may be forced so as to 1
convert it into an air-lock chamber within which the men may effect the necessary
repairs. The bottom of the well is separated from the tunnel by means of a
door forming part of the crown of the tunnel in order to avoid the loss of power
which would occur by the throwing up of the water in the well by the screw
were the crown of the tunnel open to the well, this closure of the crown of the 2
tunnel being an essential feature of the invention.
The propeller although much better protected than when placed at the stern
is yet liable to be damaged by fouling floating objects, the consequent danger being
greater than when the screw is situated at the stern since not only the propeller
but the walls of the tunnel which form a portion of the hull may be injured and
so cause the vessel to founder were it not for the protection afforded by surround-
ing the tunnel at the part where the propeller is situated and for a certain distance
fore and aft thereof by a watertight well. The well is connected to the bottom of
the vessel at each side of the tunnel at some distance from the sides thereof and
also to the tunnel itself at the front and rear so as to wholly enclose the part of
the tunnel liable to injury. Where this is not practicable, the sides of the tunnel
may be extended upwards to form the well, a grating of iron bars being provided
in the tunnel to prevent the admission to the tunnel of any floating object of
sufficient bulk to damage the propeller.
The invention is illustrated in the drawings left with my Provisional Specification
in which Figure 1 represents a longitudinal section, Figure 2 a cross section and
Figure 3 a plan of a vessel having twin screws each situated within its own tunnel
beneath the hull. Figure 4 is a longitudinal section on a larger scale of the
tunnel and well, Figure 5 is a plan and Figure 6 a cross section on line A—B of
the same.
The same letters of reference indicate the same parts in all the figures.
F is the door closing the aperture in the crown of the tunnel E secured by
rods C. DD are inclined gratings in the tunnel for protecting the propeller.
HH are the side walls of the well or air-lock making a water tight joint with the
bottom of the hull, and K the transverse walls making a water tight joint with
the bottom and with the tunnel I so as to enclose the latter, as shown in
Figure 6. L quarters for crew. M M ship's holds. N cabins. O engines. P boilers.
R coal bunkers. TT screws, each placed in a tunnel enclosed by a well, as
described.
I

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is.
1. A vessel having the screw propeller working in a tunnel in the bottom of
the hull, the part of the tunnel in the neighbourhood of the screw being enclosed
in a watertight well extending up to the main deck and convertible into an air-
lock, the tunnel being normally separated from the well by a door, substantially
as and for the purpose specified.
2. The protection of the tunnel and screw from floating objects by gratings
applied to the tunnel, as described.
Dated this 18th day of October 1892.
P. ORIOLLE,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.