IMPROVEMENTS IN MACHINERY FOR STEERING SHIPS AND OTHER VESSELS
Year: 1875

page_text: LETTERS PATENT to Robert Duthie, of the Firm of John Duthic,
Sons, and Company, of Aberdeen, North Britain, Ship Builders, for
the Invention of "IMPROVEMENTS IN MACHINERY FOR STEERING SHIPS
AND OTHER VESSELS.”
Scaled the 28th April 1876, and dated the 30th October 1875.
PROVISIONAL SPECIFICATION left by the said Robert Duthie at the
Office of the Commissioners of Patents, with his Petition, on the
30th October 1875.
I, ROBERT DUTHIE, of the Firm of John Duthie, Sons, and Company,
of Aberdeen, North Britain, Ship Builders, do hereby declaro the nature
of the said Invention for "IMPROVEMENTS IN MACHINERY FOR STEERING SHIPS
AND OTHER VESSELS," to be as follows:-
This Invention consists in the application of two screws placed in a sole
plate over the top of rudder head. The screws are actuated by a wheel
and pinions; nuts are made to traverse backwards and forwards on the
screws by motion given to the steering wheel. These nuts have planed

page_text: surfaces, which slide on planed seats and sheers, which give great
strength and smoothness to the action of the machine. Through these
nuts steel pins are introduced, which connect the rudder by means of
a cross head thercon, in which slide blocks traverse, and through which
the steel pins enter. These pins have only to be withdrawn in order to
disconnect the apparatus from the rudder when it is necessary to steer
the vessel from amidships by means of chains connected to the tiller, as
is often the case in steamships.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Duthie in the Great Seal Patent Office on
the 29th April 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
DUTHIE, of the Firm of John Duthic, Sons, and Company, of Aberdeen,
North Britain, Ship Builders, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of October, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs, and suc-
cessors, give and grant unto me, the said Robert Duthie, Her special
license that I, the said Robert Duthie, my executors, administrators,
and assigns, or such others as I, the said Robert Duthie, 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 "IMPROVEMENTS IN
MACHINERY FOR STEERING SHIPS AND OTHER VESSELS," upon the condition
(amongst others) that I, the said Robert Duthie, 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 performed, and cause the same to be filed in the Great Scal

page_text: Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Duthie, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in
and by the following statement thereof, that is to say :-
My Invention of improvements in steering apparatus consists of an
arrangement of sliding blocks connected to a rudder head, and actuated
by horizontal screws in such a manner that great power is obtained, and
the rudder easily controlled in its various movements, while the whole
of the mechanism and apparatus can be readily thrown out of gear, or
the ship may be steered with a tiller if desired.
I construct and attach to the rudder a massive cross head, having two
sunk recesses, one at each end, to receive planed sliding blocks which
traverse forward and backward in the recesses in the direction of the
length of the cross head. Above each of these sliding blocks is another
and larger block carrying a nut or fitted with an internal screwed
thread, these blocks traversing grooves in a horizontal frame carried by
brackets from the deck, the traverse being in a direction fore and aft of
the ship. Passing through the upper blocks are strong square threaded
screws, supported at each end in bearings on the frame. Each screw is
fitted at one end with a strong spur pinion. Passing through central
bearings on the frame is a horizontal shaft fitted at one end with a
spur wheel gearing into the two spur pinions on the screws. This shaft
is prolonged through the wheel, and carries at its extreme end an ordinary
hand steering wheel.
I sometimes fix on the central horizontal shaft a small drum or chain
pulley, round which is passed a rope or chain in connection with blocks
for steering from amidships or by the tiller aft.
In order that my Invention may be better understood, and more
readily carried into operation, I will now proceed to describe and explain
the Sheet of Drawings hereunto annexed.
Figure 1 is an end elevation; and Figure 2, a plan of my improved
apparatus.

page_text: as above, fitted also with a drum, chains, and blocks when required for
steering from amidships.
A, A, is a strong cross head attached to the rudder, and having two
planed recesses or grooves B, B, one at each end; within these recesses
or grooves slide blocks C, C, connected by vertical pins to the upper
and larger sliding blocks D, D, which are screwed with internal screwed
threads, and act the part of nuts sliding in longitudinal grooves E, E, of
the frame F, F, this frame being supported at each end on standards G, G ;
H, H, are strong screws having right and left hand threads working in
the sliding blocks D, D; these screws are supported at each end running
in bearings K, K, on the frame F, F. Two other bearings L, L, also
carried by the frame F, F, serve to support the central horizontal
shaft M, carrying a spur wheel or pinion O, gearing into and driving
the pinions N, N, on the screws. At the extreme end of the central
shaft is fixed an ordinary hand steering wheel P, P. On turning the
wheel motion is communicated through the wheels O, N, N, to the
screws H, H, and sliding blocks D and C, and thence to the cross head
and rudder. By removing the pins from the sliding blocks the screws
are disconnected from the rudder, which may then if required be worked
by a tiller; Figure 3 shews an arrangement for working by a wheel
amidships. In this case the same general arrangement of screws and
sliding blocks is used as before described, but in addition a chain pulley
or drum P is fixed on the end of the central shaft opposite the steering
wheel, and round this drum or chain pulley is passed a rope or chain R, R,
passing also round blocks S, S. From these blocks chains are passed to
a wheel amidships, which will then actuate and control the rudder in
the same manner as the wheel at the stern would do.
Having now particularly described and ascertained the nature of my
said Invention, and how the same may be carried into practical operation,
I would have it understood that what I claim and desire to secure by
the herein-before in part recited Letters Patent is,―

page_text: And, Second. The arrangement of drum or chain pulley blocks and
chains in connection with the before-mentioned arrangement for working
the rudder from aft or amidships, as herein-before described and illus-
trated by accompanying Drawing, Figure 3.
In witness whereof, I, the said Robert Duthic, have hereunto set
set my hand and seal, this Twenty-ninth day of April, in the
year of our Lord One thousand eight hundred and seventy-six.
ROBERT DUTHIE. (L.S.)