Improvements in the Method of Propelling Ships by Screw Propellers, and in the Arrangement of the Construction of the Vessels for Accomplishing it.
Year: 1893

page_text: Date of Application, 18th Dec., 1893-Accepted, 17th Feb., 1894
COMPLETE SPECIFICATION.
Improvements in the Method of Propelling Ships by Screw
Propellers, and in the Arrangement of the Construction of
the Vessels for Accomplishing it.
I, GEORGE AUGUSTUS HAIG, of Pen Ithon, Radnorshire, Justice of the Peace
for said county, and of No. 7, Argyll Street, London, W., Merchant, and of
No. 236, Fulham Road, London, S.W., Manufacturer, 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 :-
Heretofore screw propellers for a ship have only been used in small numbers
usually for each vessel one or two or three at the stern of the vessel, and occasionally
one or two at the bows, but the propellers have always been placed outside the
frame of the ship.
Now my invention is to place them practically inside the frame of the ship, that
is to say, inside one or more open water channels running in a fore and aft direction
straight through the vessel-if there be only one such channel the bottom of the
ship would form the bottom of the channel if it were a square channel for one line
of screw propellers, or if it were an oval made of two half circles separated from
each other by two parallel lines horizontal and each line the length of the diameter
of the semi-circular ends so as to leave room for two lines of screw propellers, and
the perpendicular plane which passes through the stem and the stern of an ordinary
ship would divide this channel exactly in half-but if there were two or more
channels each containing a line of propellers they would be so arranged that one
half of them would lie on each side of the before-named perpendicular plane. passing
through the stem and stern of an ordinary ship, and parallel to it. Each channel
begins with the skin of the fore part of the vessel and ends with the skin of the
after-part of the vessel, and is neatly and strongly joined to the skin, and in this
way the water has a clear way through the channel obstructed only by the pro-
pellers, their shafts, cranks, and necessary supports and gearing for working them.
But every channel will have two sluices (one near the entrance, the other near the
exit of the water) or some other suitable arrangement to close the channel water-
tight so that by pumping out the water access can be got to the propellers at any
time (even at sea), but when the propellers are at work the channels must be open
at both ends so as to allow the water to pass through.
Now when only one line of propellers is used (and in a long ship, although I by
no means limit myself to one line only, I think one line of propellers will be found
to be enough) I would make the channel a square, one side of the square being
formed by the bottom of the ship, and the fore end of this channel would end where
the breadth of the ship was the same as the chanuel, and then each perpendicular
side of the channel will form with the skin of the ship a sharp edge like the half of
a "cut-water," as shown in Fig. 1, while the fore part of the ship above the top of
channel will be carried on as shown by the dotted lines to form a cut-water for
the upper portion of the ship, the bottom of this fore part being practically a
continuation of the top of the water channel, and a perpendicular section of the
ship at the fore end drawn in the perpendicular plane which runs through stem and
stern would have the appearance shown in Fig. 2.
Now the sluice which closes the forward end of the channel is placed well back
from the mouth of the channel because possibly we may have to cut away a portion
of the bottom of the channel to give ingress for the water if at any time the pitching
of the ship raised the bottom edge of the channel above the level of the water.
But the hinder end or stern end of this square channel runs right back to the stern

page_text: .
of the ship and each perpendicular side of the channel ends in a perpendicular rudder
post, to each of which a rudder is fixed so that the ship has two rudders as shown
in Fig. 3, which two rudders of course will be connected together so as to make
them move synchronously together.
Now I can mount in my channels any approved pattern of screw propeller and
can support it in the usual way on perpendicular or on horizontal supports fixed
inside the channel in the water with plummer blocks and all suitable and usual
contrivances for receiving the thrust of the various propellers in pushing the ship
through the water, and these propellers I can place on one continuous shaft at
proper intervals and with as many cranks upon it as I think fit, or I can make a
number of short shafts all laid in the same line and connected together by the
cranks all worked by engines placed half on one side and half on the opposite side
of the channel and working the cranks by sliding rods through water-tight stuffing
boxes in the sides of the channel and connecting rods between the cranks and the
sliding rods so arranged and connected together that the whole line of propellers
must revolve synchronously together, or instead of complete propellers 1 may fix
single blades at suitable intervals along the whole line of shafting.
Now the number of propellers or blades and the size of the propellers will
depend on the size of the ship and the speed at which it is intended to be driven,
because by my arrangement of propellers inside the frame of the ship and in one or
more continuous lines one behind the other I can get a much greater area of
propelling surface into effective operation than is possible with the present usual
arrangement of propellers outside the frame of the ship at the stern, and by this
increased propelling surface driven at a suitable speed I can drive ships (well
constructed and strongly built) through the water at a very much higher speed
than has ever yet been reached with screw steam ships.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is :-
1. The placing of screw propellers, wholly inside the frame of the ship in suitable
fore and aft channels open at both ends but closable when wished.
2. The arranging of screw propellers one behind the other in a continuous fore
and aft line each mounted on its own separate shaft with cranks to connect it with
the shaft before it or with the shaft behind it or with both of them with proper
supports and collars to receive the thrust of the propeller and so arranged as to
make the whole revolve synchronously.
3. The working of these continuous lines of screw propellers by steam or other
motive engines placed on one side or both sides of the water channel acting on
sliding rods passing through water-tight stuffing boxes in the sides of the channel
with connecting rods between the said sliding rods and the cranks on the propeller
shafts which being connected together make the whole revolve synchronously.
4. The working of a great many separate blades of a screw propeller placed at
considerable distances from each other on one long line of continuous shafting with
several cranks upon it placed inside a water channel in a ship with open ends as
described, and driven by several engines on each side as described acting on the
various cranks of the shafting.
Dated this 11th day of December 1893.