IMPROVEMENTS IN APPARATUS AND MEANS FOR INDICATING THE POSITION OF A SHIP'S HELM
Year: 1883

page_text: LETTERS PATENT to John Evelyn Liardet of Brockley in the County of
Kent for an Invention of "IMPROVEMENTS IN APPARATUS AND MEANS FOR
INDICATING THE POSITION OF A SHIP'S HELM
PROVISIONAL SPECIFICATION left by the said John Evelyn Liardet at the
Office of the Commissioners of Patents on the 26th June 1883.
"IMPROVEMENTS
"8
JOHN EVELYN LIARDET of Brockley in the County of Kent
IN APPARATUS AND MEANS FOR INDICATING THE POSITION OF A SHIP'S HELM
This invention has for its object improvements in apparatus and means for
indicating the position of a ship's helm.
For this purpose I arrange that the movement of the rudder to port or to
starboard shall effect the closing of one or other of two electric circuits. In each
of these circuits I arrange an electric lamp so that one lamp is in operation and
shows light when the rudder is to port and the other when the rudder is to star-
board. When the rudder is amidships both lamps are extinguished. These lights
are used in addition to the ordinary ships lights and are conveniently placed in the
fore top or in the fore rigging. Similarly I arrange for the sounding of distinctive
electric bells and gongs when the rudder is moved to port or to starboard.
Also by means of such circuits I provide for the constant registration of the
movements of the rudder; the record is kept upon a travelling surface moved by
clock work and the movement of the rudder produces by electrical means distinc-
tive marks upon this surface. By a subsequent examination of this record. the
direction of any movement of the rudder and the time when it occurred can be
accurately ascertained,
The light and sound signals serve to prevent collisions and to denote the ships
course especially when meeting or passing a ship.
The record forms a complete and correct register or log of the ship's course and
movements of the rudder from which at any subsequent time reliable information
can be obtained.

page_text: I fix a platform of wood or other suitable non-conducting substance upon the
ship's deck or in any other suitable position.
An aperture is provided in the centre of the platform for the rudder head to
pass.
A recess extending over a segment of a circle say 100 degrees is formed beneath
the platform to allow the free movement of the tiller attached to the rudder.
Upon the upper face of the platform I place two separate sections of circles of
plates of copper, brass or other suitable metal, or substance to act as electric
connectors.
To make contact with these I provide copper or other metal springs or arms on
the rudder stem a convenient height above. the circle connectors. Theso apring
arms are bent or bowed and each is to rest upon and move upon the circle connector
with the movement of the rudder.
When the switches are on, the electric circuits will only be broken, when the
rudder is in midships or in direct line with the ships keel.
I fit a wood collar or other suitable separator over the rudder stem to rest upon
the first spring arm so as not to weaken the rudder stem and to separate at a
proper distance a second and precisely similar spring or arm which I also fit over
the rudder stem and rest it on to the collar separator. This spring or arm will also
require to be bent or bowed to touch the outer circle plate connector.
I fit electric switches in the wheel house or any other convenient position on
board ship for opening the circuits when the light and sound apparatus is not
required and also switches whereby I can if necessary by a hand operation exhibit
a white light at the mast head and a blue light at the stern' when the rudder is
amidship and also give a sound indication of the same purport.
The port switch turns on or off the red port light or lights by the action of the
rudder when over to port. And vice versa the starboard switch turns on or off
the starboard green light or lights instantly by the action-of-the-rudder. when over
to starboard.
I fit also three several switches for the electric bells and gong or gongs or other
suitable sound signals
The bells and gong signals will also be worked direct by the action of the rudder.
To duly record upon the travelling.surface of the tell tale electric clock apparatus
already referred to whenever the auxiliary lights or the bells and gong signals are
employed I provide an independent and separate electric battery or other convenient
electric system.
I propose to use the Liardet and Donnithorne electric secondary battery for
keeping up and storing the electricity generated by the ordinary well known
system of dynamo machinery to be worked by the ships engines or by a steam
engine worked from an auxiliary boiler.
I prefer to set the dynamo or dynamos in motion directly from the propellor
shaft in the case of screw steamers and to fit pulley wheel gearing to the propellor
shaft in a vertical line with the wheel house wherein I propose to place the
dynamo or dynamos and secondary battery accumulators. I thus supply a continuous
current of electricity for charging and storing in the secondary batteries to supply
all the requirements for the light and sound signals and electric lighting of the ship
generally.
I thus obtain the electric energy in the most economical and effective manner
taking up the least possible space in the ship where no cargo can be stored.
I also provide a switch to be used in thick or foggy weather for discharging
electric or other rockets in rapid succession ahead or from any other part of the
ship as distress signals.
,
To obtain the record of the movements of the rudder and of the light and sound
signals I connect the current wires with the secondary battery accumulators or other
electric system and include in the circuits the electrical arrangements of a tell tale
electric clock.
3

page_text: In place of the paper tape usually employed in tell tale clocks for preserving a
record I use oiled silk or thin metal so that in case of a collision and the ship
sinking the tape and its record may be preserved. To ensure this the tape should
be of a material which will bear prolonged immersion.
The record of the rudder movements illumination of the several lights the signals
sounded and distress signals & and the time of so doing forming a complete and
correct log of the said several signals.
I place this tell tale clock in a convenient place in the chief cabin or saloon of
the ship and also provide communication with the Captains and Officers' cabins,
the bridge or any part of the ship where it may be necessary.

page_text: .
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Evelyn Liardet in the Great Scal Patent Office on the
22nd December 1883.
JOHN EVELYN LIARDET of Brockley in the County of Kent
"IMPROVEMENTS
IN APPARATUS AND MEANS FOR INDICATING THE POSITION OF A SHIP'S HELM
"
-This invention has for its object improvements in apparatus and means for
indicating the position of a ship's helin.
For this purpose I arrange that the movement of the rudder to port or to
starboard shall effect the closing of one or other of two electric circuits. In cach
of these circuits I arrange an electric lamp so that one lamp is in operation and
shows light when the rudder is to port and the other when the rudder is to star-
board. When the rudder is amidships both lamps are extinguished. These lights
are used in addition to the ordinary ships lights and are conveniently placed in the
fore top or in the fore rigging or any other part of the ship. Similarly I arrange
for the sounding of distinctive electric bells and gongs when the rudder is moved
to port or to starboard.
Also by means of such circuits I provide for the constant registration of the
movements of the rudder; the record is kept in a well known manner upon a
travelling surfaco moved by clockwork and the movement of the rudder produces
-by-electrical means distinctive marks upon this surface. By a subsequent examina-
tion of this record the direction of any movement of the rudder-and-the-time. when.
it occurred can be accurately ascertained.
The light and sound signals serve to prevent collisions and to denote the ships
course especially when meeting or passing a ship.
The record forms a complete and correct register or log of the ships course and
movements of the rudder from which at any subsequent timo reliable information
can be obtained.
I fix a platform of wood or other suitable non-conducting substance upon the
ship's deck or in any other suitable position.
An aperture is provided in the centre of the platform for the rudder head to
pass.
A recess extending over a segment of a circle say 100 degrees is formed beneath
the platform to allow the free movement of the tiller attached to the rudder.
Upon the upper face of the platform I place two separate sections of circles of
plates of copper brass or other suitable metal or substanco to act as electric
connectors.
To make contact with these I provide copper or other metal springs or arms on
the rudder stem a convenient height above the circle connectors. These spring
arms are bent or bowed and each is to rest upon and move upon the circle connector
with the movement of the rudder.
When the switches are on the electric circuits will only be broken when the
rudder is in midships or in direct line with the ship's keel.
1 fit a wood collar or other suitable separator over the rudder stem to rest upon
the first spring arm so as not to weaken the rudder stem and to separate at a
proper distance a second and precisely similar spring or arm which I also fit over
the rudder stem and rest it on to the collar separator. This spring or arm will
also require to be bent or bowed to touch the outer circle plate connector.
Figure 1 is an elevation partly in section of the apparatus in connection with
the rudder,
1 is the rudder head and 2 and 3 are bow springs mounted upon it and

page_text: insulated from one another-each of these springs rubs upon a circle of metal
which is divided into segments.
Figure 2 is a plan of these segments, those marked a a¹. a². control the light
signals and those marked b. b. b. the sound signals. The segment a connected up
with the source of electricity through a switch placed in any convenient position
in the ship and which is used to prevent the exhibition of the lights when they
are not required. One end of the bow spring 2 is always in contact with a.
When the rudder is midships the other end of the spring 2 drops into a notch
between a¹ and a thus breaking contact. When the helm is moved to port the
end of tho spring 2 is moved out of the notch on to a² or when to starboard on
to a¹. In the first case the electric current flows from a through 2 to a². a² is
connected by an insulated wire with the red or "Port" electric lamp and through
this with the electric source so that when 2 bears upon a (unless the switch be
open) the circuit is complete and the light is shown. a¹ is similarly connected
with the "Starboard" which is shown when 2 rests on a' unless the switch be
open.
The parts b. b. b3 and 3 operato in a similar manner except that the lights are
replaced by electric bells.
I fit electric switches in the wheel house or any other convenient position on
board ship for opening the circuits when the light and sound apparatus is not
required and also switches whereby I can if necessary by a hand operation exhibit
a white light at the mast head and a blue light at the stern when the rudder is
amidships and also give a sound indication of the same purport. Figure 3 shows
the switch board.
The port switch turns on or off the red port light or lights by the action of the
rudder when over to starboard.; And vice versu the starboard switch turns on or,
off the starboard green light or lights instantly by the action of the rudder when
over to port.
I fit also two several switches for the electric bells and gong or gongs or other
suitable sound signals.
The bell and gong signals will also be worked direct by the action of the rudder.
To duly record upon the travelling surface of the tell tale electric clock apparatus
already referred to whenever the auxiliary lights or the bell and gong signals are
employed I sometimes provide an independent and separato electric battery or other
convenient electric system.
I propose to use the Liardet and Donnithorne electric secondary battery for
keeping up and storing the electricity generated by the ordinary well known
system of dynamo machinery to be worked by the ship's engines or by a steam
engine worked from an auxiliary boiler.
I prefer to set the dynamo or dynamos in motion directly from the propeller
shaft in a vertical line with the wheel house wherein I propose to place the dynamo
or dynamos and secondary battery accumulators. I thus supply a continuous
current of electricity for charging and storing in the secondary batteries to supply
all the requirements for the light and sound signals and electric lighting of the ship
generally. The arrangement is represented in Figure 4.
I thus obtain the electric energy in the most economical and effective manner
taking up the least possible space in the ship where no cargo can be stored.
I also provide a switch to be used in thick or foggy weather for discharging
electric or other rockets in rapid succession ahead or from any other part of the
ship as distress signals.
To obtain the record of the movements of the rudder and of the light and sound
signals I can connect the current wires with the secondary battery accumulators or
I may use other electric systems and include in the circuits the electrical arrange-
ments of a tell tale electric clock.
Circuits in connection with the battery or electric source are opened and closed
in the manner already described in respect to the light and sound signals by the

page_text: movement of the rudder and these currents operate points or markers tracing upon
the travelling surface.
In place of the paper tape usually employed in tell tale clocks for preserving a
record I use oiled silk or thin metal so that in case of a collision and the ship
sinking the tape and its record may be preserved. To ensure this the tape should
be of a material which will bear prolonged immersion.
The record of the rudder movements illumination of the several lights the signals
sounded and distress signals &c and the time of so doing forming a complete and
correct log of the said several signals.
I place this tell tale clock in a convenient place in the chief cabin or saloon of
the ship and also provide communication with the Captain's fand · Officers cabins,
the bridge or any part of the ship where it may be necessary.
What I claim is
First Connecting with the rudder-a circuit regulator closing and opening the
circuits of port and starboard electric lights or electric bells substantially as
described.
Second-Registering automatically by electric mechanism on a travelling surface
the movements of the rudder substantially as described.
Third-The combination' with apparatus for indicating the position of a ship's
helm of dynamo machinery driven from the propeller shaft and secondary batteries
forming an economical source for the continuous supply of electricity substantially.
as described.
Fourth My improvements in apparatus and means for indicating the position
of a ship's helm substantially as described.
In witness whereof I the said John Evelyn Liardet have hereunto set my
hand and seal this Eleventh day of December in the year of our Lord One
thousand-eight hundred and eighty three.
TEVETVN TTADDE