IMPROVEMENTS IN RUDDERS AND IN MACHINERY OR Steering Gear FOR WORKING RUDDERS."
Year: 1875

page_text: LETTERS PATENT to George Daniel Davis, of 16, Woodstock Road,
East India Road, Poplar, Ships' Mechanist, for the Invention of
"IMPROVEMENTS IN RUDDERS AND IN MACHINERY OR Steering Gear FOR
WORKING RUDDERS."
PROVISIONAL SPECIFICATION left by the said George Daniel Davis
at the Office of the Commissioners of Patents, with his Petition,
on the 9th July 1875.
I, GEORGE DANIEL DAVIS, of 16, Woodstock Road, East India Road,
Poplar, Ships' Mechanist, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN RUDDERS AND IN MACHINERY OR STEERING
GEAR FOR WORKING RUDDERS," to be as follows:-
This Invention of improvements in rudders and in machinery or
steering gear for working rudders consist,―
Firstly. In a construction of rudder capable of being extended in its
area when the requirements of the service the rudder has to perform
renders it desirable.

page_text: head at the stern of the ship.
And, Thirdly. In the arrangement of the mechanism in connection
with the wheel when the rudder has to be worked from amidships or
some distance from the rudder head.
The first improvement consists in making the rudder in the form of a
hollow iron case within which works a moveable plate, which falling
outwards from between the walls of the case extends the area of the
rudder surface and so gives greater action upon the vessel. The middle
plate of the rudder is hinged or fastened by a pin which passes through
the outer plates of the hollow case, and upon this pin at the lowest part
of the rudder the movable plate works from its upper part and extending
backwards towards the wake of the ship. I prefer to make the case
and extending centre plate of the rudder of iron; it may be made to
act by a chain on pulleys, which when lengthened allows the centre
plate to project from its upper end into the water, or it may be drawn
completely into the case. One convenient manner.consists in applying
a short tiller to a pulley from the extremity of which tiller a chain
passes over pulleys to the upper part of the centre plate. From the real
tiller head an endless chain is passed over two pulleys on the sides of
the vessel or fastened to the deck, and round a sheave or pulley forming
the centre of the motion imparted to the short tiller,, so that when the
rudder is put to port or starboard the short tiller works to aft and
slackening the chain allows the plate to extend and provide a larger
area, or when moved to its point in the line of the keel of the vessel
draws-the-extending-plate_within the case.
In the second improvement the cross head of the rudder is worked by
a longitudinal screw or screws working levers in connection with the
cross head; the nuts of the screws to which the levers are attached work
in trunks or tubes; an arm of the nut projects upwards through long
slots in the tubes; to this projection the levers are fitted..
In the third improvement I fix a short drum in a frame on the deck,
the axle in line with the kecl; the drum carries a toothed wheel which
is driven by a worm wheel; the axle of the worm wheel is extended
upwards and carries a bevil wheel which gears into another bevil
wheel, this latter being on the axle of the steering wheel; the drum

page_text: carries two or three turns of chain which leads off to port and starboard,
thence along the sides of the vessel, and across to the tiller of the rudder
over pulleys in the ordinary manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Daniel Davis in the Great Seal Patent
Office on the 8th January 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
DANIEL DAVIS, of 16, Woodstock Road, East India Road, Poplar, Ships'
Mechanist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of July, 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 successors, give
and grant unto me, the said George Daniel Davis, Her special license
that I, the said George Daniel Davis, my executors, administrators, and
assigns, or such others as I, the said George Daniel Davis, 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 "IM-
PROVEMENTS IN RUDDERS AND IN MACHINERY OR STEERING GEAR FOR WORKING
RUDDERS," upon the condition (amongst others) that 'I, the said George
Daniel Davis, 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 Seal Patent Office within six calendar
months next and immediately after the date of the said Letters
Patent.
•
NOW KNOW YẺ, that I,. the said George Daniel Davis, 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 ;-

page_text: This Invention of improvements in rudders and in machinery or
steering gear for working rudders consists, -
Firstly. In a construction of rudder capable of being extended in its
area when the requirements of the service the rudder has to perform
renders it desirable.
Secondly. In the arrangement of screw gear for working the rudder
immediately at the stern of the ship.
And, Thirdly. In the arrangement of the mechanism in connection
with the steering wheel when the rudder has to be worked from
amidship or some distance from the rudder head.
In the accompanying Drawings forming part of this Specification,—
Sheet 1. First Improvement.-Figure 1 is a plan of the rudder head
and chain gearing in connection with the extending rudder; Figure 2, a
side elevation of the same in connection with the stern post of a vessel,
the rudder extended; and Figure 3, a side elevation, the rudder being
contracted to its normal dimensions.
Sheet 2. Second and Third Improvements.-Figure 1 A, plan of the
rudder head and gearing in connection with the wheel under the second
improvement; Figure 2 A, side elevation of the same, and Figure 4A,
end elevation of the same; Figure 4B, Figure 5 B, Figure 6 B, plan, end,
and side elevation of one of the forms of the third improvements;
Figure 7 C, Figure 8 C, and Figure 9 C, side elevation, end clevation,
and plan of another form of the third improvement; and Figure 10 D
and Figure 11 D, end and side elevation of a modification under the
third improvement, the like letters in each group referring to the like
parts.
First Improvement.-a is the stern post of the ship; b, the rudder head;
the rudder itself c is formed of two sides forming a hollow case between
which lies the plate & hinged on a pin at d', and supported in sliding into
or out of the case by four arms, two only of which are shown, namely,
d', d', sliding in corresponding lugs d; a chain d³ fastened to the
extending plate dat d³ is the means by which the plate is let down or
extended as in Figure 2, or drawn into the case as in Figure 3; this
chain is put in action in the following manner:--The tiller &¹ carries
a pin b² which is passed through a link of the endless chain * when the
extension of the rudder is required; this chain is lapped round the

page_text: pulley e and passes round the pulleys e³ and e³, all secured to the deck;
as the tiller works to port or starboard the pulley e elongates or shortens
the chain which passes over the pulley d round the pulley of the
connecting rod e¹ to the pin d³ by means of the pin e' in connection
with the pulley e acting as an eccentric, thus when the rudder is hard
to port or starboard the rudder d is extended, and whilst admidship
the rudder d is withdrawn into the case; when the extension is not
required the pin 62 is removed and the connecting link e' fixed by a pin,
so that the rudder remains within the case in any position of the tiller
head. It is obvious that the exending rudder might itself be made the
case and then work over the rudder proper, so as to be of easy adoption
to existing rudders, or it may be made of one plate and fastened to the
ordinary rudder by the pin, as shown at d', the guides and stays d¹
being as described, but the first described arrangement is I think the
best.
Second Improvement for Steering at the Stern of the Vessel.-The
Drawings, Figure 1A, Figure 2 A, and Figure 3A, show the second
improvement a and b, two screws right and left-handed geared by the
wheels c and d into the wheel e on the shaft which carries the steering
wheel; each screw works in brass nuts respectively a¹, 61, connected by
the links or couplings a², 6³, to the cross head 7 keyed on the rudder
head ; the nuts a', 6', are also guided by the guide rods a*, b**, passing
through them and shown in Figure 1A, and the ends in Figure 3A;
the whole mounted and supported in the strong framing i of iron
cast or wrought, or partly in both, or other suitable material.
v
Third Improvements for Steering Gear away from the Stern, of the
Vessel or on the Bridge.-Figures 4B, 5 B, and 6B represent one form
of these improvements. a is the steering wheel axle carrying, the worm
wheel b, gearing into the pinion c on the vertical shaft d, carrying the
pinion e, gearing into the spur wheelf on the shaft g; this shaft carries
the horizontal pulleys h, i, which carry the chains leading to the tiller
head, and which may be carried in any suitable manner; % is the
supporting framing in iron.
Figure 7 C, 8 C, and 9 C is another form of the distant steering gear.
also with horizontal leading pulleys. a is the wheel shaft carrying the
worm wheel 6 driving the pinions c, d, connected by the shafts e, f, with
the horizontal pulleys g, h, round which are led the chains to be taken in

page_text: any suitable manner to the tiller, the whole enclosed in the strong
framing of iron or other suitable material i, which in all the described
improvements is suitably fixed to the decks or framing of the ship.
a is
Figure 10 D and Figure 11 D show one of the forms of distant
gearing having vertical pulleys for the leading chains to the tiller.
the wheel shaft carrying the mitre wheels b, c, the latter keyed on the
shaft d, carrying the worm wheel e, driving the spur wheel f, upon the
shaft I, which carries the pulleys h, i, for the leading chains; the whole
carried in a suitable framing of iron and securely fastened to the deck
or framing of the vessel.
Having now described and particularly set forth the nature of the
said Invention and the manner of carrying the same into effect, I would
have it understood that what I claim is,
-
Firstly. The expanding rudder working in the case rudder or over
the rudder or on one side of it, substantially as described.
Secondly. The expanding rudder actuated by the movement of the
tiller head, and the chains and connections substantially as described.
Thirdly. The steering wheel gear described under the second improve-
ment with the right and left screws geared and connected with the
rudder head, substantially as described.
Fourthly. The bridge or distant wheel steering gear described under
the third improvements, substantially as described.
In witness whereof, I, the said George Daniel Davis, have here-
unto set my hand and seal, this Fifth day of January, in the
year of our Lord One thousand eight hundred and seventy-
six.