A Signalling Apparatus for Preventing Collisions between Vessels at Sea.
Year: 1899

page_text: Date of Application, 12th July, 1899
Complete Specification Left, 27th Feb., 1900-Accepted, 16th June, 1900
PROVISIONAL SPECIFICATION.
A Signalling Apparatus for Preventing Collisions between Vessels at
Sea.
I, THEODORE HERMAN HELENES BODDE, of 47, Quai de Grenelle, Paris, in the
Republic of France, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention relates to an application of the principle of wireless telegraphy
for the production of an instrument capable of indicating the situation of a
vessel and even the direction in which it is proceeding on board another vessel
in proximity to the first, and which is not visible by reason of fog or darkness.
The said application of this principle may be effected in three distinct ways
which I will hereinafter describe.
The first form of execution and the one which I consider the most efficacious
consists in arranging upon each of the two vessels, on the one hand a vertical
radiator of any suitable kind provided with a parabolic reflector, and which is
caused to rotate slowly around its axis by means of any suitable mechanism;
and on the other hand a resonator arranged at a sufficient distance from this
radiator, preferably above it and in the prolongation of its axis, in order that it
This resonator is
may not be influenced by the radiations of this apparatus.
capable of receiving radiations coming from all points of the horizon. I will
not describe these appliances in detail as they are similar to those employed in
the art of wireless telegraphy although I reserve the right to establish them with
all the improvements of which this branch of science is capable.
If we consider the double radiator-resonator apparatus of one of these vessels
during the time this resonator is sensitizing its coherer, under the influence of
the radiations of another radiator, which can only be that of a vessel in the
neighbourhood of the vessel which we are considering, a current produced in the
manner known in wireless telegraphy is dispatched into an electro magnet which
opens the valve of a steam whistle or any other suitable alarm apparatus. Those
in charge of the second vessel are then warned of the proximity of another vessel;
immediately the officer in charge of this second vessel inspects a dial over which
moves an indicator which is rigidly connected with the radiator of his vessel or
connected with this radiator by means of any appropriate intermediate parts, but
in such a manner as to participate in the movement of rotation of this latter.
At the moment when this whistle or other signal is given, the indicator occupies
a position and direction indicating the position and direction of the vessel which
is to be avoided.
The same phenomenon takes place upon the other vessel. In accordance with
the second manner of carrying my invention into practice the apparatus upon
each of the two vessels comprises a vertical radiator of any suitable kind and a
resonator arranged at a sufficient distance above the radiator in the prolongation
of the axis of this latter in order that it may not be influenced by the radiations
proceeding therefrom. The radiator emits its waves towards all points of the

page_text: horizon and the resonator is provided with a parabolic reflector; it is caused to
rotate slowly around its axis by means of any suitable mechanism. During the
time that this resonator is sensitising its coherer under the influence of the
radiations of another radiator, which can only be that of a neighbouring vessel,
a current produced in the same inanner as in wireless telegraphy actuates an
alarm apparatus of any suitable kind. At this moment the officer in charge of
this same vessel, warned by the signal, inspects a dial over which travels an
indicator which is rigidly connected with the resonator by means of any appro-
priate parts. During the operation of the alarm, this indicator has a direction
and position indicating the direction and position of the vessel which is to be
avoided.
The apparatus with which the other vessel is provided acts in the same manner.
The third manner of carrying my invention into practice, consists as regards
each vessel upon the one hand of a horizontal radiator of circular form which
thus dispatches in all directions vertically polarised, magnetic waves. Above
this radiator is arranged a horizontal resonator in such a manner that it is not
influenced by the radiations of this radiator. This resonator rotates in a hori-
zontal plane around its centre. When it is pointed in the direction of the
radiator of the adjacent vessel, the coherer is not sensitised; when it is pointed in
a direction perpendicular to this first named direction, the coherer is sensitised
and the alarm is actuated and the navigating officer is then able to see by means
of the indicator what is the position of the neighbouring vessel. In order that
the resonator may also indicate the direction, it is necessary to add a parabolic
reflecting screen, or merely a cylindrical screen.
It will be noticed that with the three forms of execution of the invention, the
following means may be employed in order that the resonator may not be
influenced by the radiator of the same vessel. The radiator is caused to operate
intermittently by means of a commutator actuated by any suitable mechanism
and in such a manner that the circuit of the coherer is cut upon both sides during
the time that the circuit of the radiator is closed, and is closed during the time
that this circuit remains open.
In order to obtain the maximum effect, small wave lengths should be employed
in all three forms of execution.
By this means vessels will not disclose their mutual proximity except at a
distance of 50, 100 or at the most 200 metres.
Dated this 1941.
LTL 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
A Signalling Apparatus for Preventing Collisions between Vessels at
Sea.
I, THEODORE HERMAN HELENES BODDE, Electrical Engineer, of 47, Quai de
Grenelle, Paris, in the Republic of France, and 5, Osnaburgh Terrace, Regent's
Park, in the County of London, 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 :-
This invention relates to improvements in apparatus for preventing collisions
at sea and has for its object the provision of means whereby ships may com-
municate with each other by means of Hertzian or similar waves, the apparatus

page_text: on one ship giving an indication of the direction in which the other vessel is
situated.
According to this invention each vessel is provided with a transmitter and a
receiver. The transmitter comprises a Hertzian oscillator of improved con-
struction which is placed in the focal line of a parabolic reflector. Preferably
the shape of the reflector and the length of the oscillator are such that the distance
between the focal line and the nearest wall of the reflector is approximately equal
to a quarter of the length of a wave produced by the oscillator. This arrange-
ment is found to be very efficient and what may be termed a dense bundle or
stream of parallel rays is projected from the apparatus. The reflector with its
oscillator is arranged vertically and is capable of being rotated upon a vertical
axis so that the parallel waves may be projected to any point of the compass.
Means, such as a pointer moving over a graduated dial, are provided so that the
position of the reflector at any moment may be observed.
The receiver comprises a coherer and is preferably placed beneath the trans-
mitter. In order that there shall be no risk of the coherer being actuated by
waves emitted from its own transmitter, a commutating device is provided-
preferably operated by the rotation of the transmitter-which operates to put the
transmitter and receiver alternately in and out of circuit.
The coherer is joined in the usual way to an electric cell and a relay and the
latter is caused to operate the local circuit connected say to an electro-magnetically
controlled steam whistle or other acoustic or optical signalling apparatus.
It is obvious that if two vessels are fitted with apparatus according to this
invention and the transmitter on the one ship actuates the coherer upon the
other vessel, thus causing its steam whistle to sound, the steersman on the first
vessel upon hearing the whistle can, by looking at the dial upon his transmit-
ting apparatus, ascertain at once in what direction the second ship is situated.
The improved oscillator according to this invention comprises a long tube of
glass or other insulating material in which is placed a series of metallic ball's
separated at equal distances by means of short tubes of insulating material. It
is found that an oscillator constructed in this manner, when joined up in a
circuit of which the capacity and self induction are suitably adjusted, will enable
waves of a small length to be felt at a distance greater than at which the ordinary
form of oscillator is operative.
In a modified construction of apparatus according to this invention the risk
of the receiving apparatus being actuated by waves from its own transmitter is
obviated by the employment of more than one receiver. The coherers of these
receivers are joined in series and the receivers are so placed relatively to the
transmitter that it is impossible for waves proceeding from the latter to affect
all of them, although all the coherers will be actuated by waves sent from an
outside source.
In the accompanying drawings which illustrate one construction of apparatus
according to this invention
Figure 1 is a vertical section.
Figure 2 a plan with portions removed.
Figures 3 and 4 are plans showing in detail two portions of the receiving
apparatus.
Figure 5 is a central vertical section of a portion of the oscillator.
Figure 6 is a diagram illustrating the modified arrangement where the trans-
mitter is placed between more than one receiver.
Like letters indicate like parts throughout the drawings.
A is the bridge or other portion of the ship convenient for supporting the
apparatus. Upon it is a casing A¹ and below it another casing A². These
casings are preferably made of insulating material paraffined wood for instance,
and respectively contain the transmitting and receiving devices. Rotatably
mounted within the casing A¹ is a parabolic reflector B which may conveniently
be made by constructing a form of paraffined wood and covering this form on the

page_text: outside with metallic plates. The top and bottom of the parabolic reflector B
are attached to discs B and B and the disc B₁ carries a toothed ring B³ which
engages with and is driven by a gear wheel B rotatably mounted in the casing A'.
A crank handle B attached to the spindle of the gear wheel B affords means
for rotating the transmitter. The disc B₁ is provided with a pivot or trunnion Bo
which runs in a bearing or guide in the top of the casing A and carries a
pointer B which moves over a graduated dial 138 fixed to the casing A¹. The
bridge A is perforated in order to form a bearing for a sleeve or trunnion B⁹
situated centrally on the bottom disc B. Up through the centre of this trun-
nion B passes a stationary shaft C which is supported by a cross piece A³ attached
to the casing A². Upon the top of this stationary shaft C is a gear wheel C¹
and a similar wheel C2 is carried upon the bottom of the trunnion B. The
wheel C¹ gears with a pinion (3 upon a spindle C, the ends of which are pivotted
in the disc B2 and a cross-piece B10 which extends across the reflector B.
disc is carried upon the spindle C and serves as a commutator to cut the
'oscillator in and out of circuit.
A
The disc C is of insulating material but is provided with a metal piece Co
(Figure 2) and this metal piece makes contact with and connects two springs C
which are mounted upon the cross piece B", thus bridging over a gap in the
primary circuit and induction coil hereinafter mentioned.
The oscillator is mounted between the cross-piece 1310 and a similar piece B
at the upper portion of the reflector B. It comprises a tube I preferably of
glass, containing within it a series of metallic spheres 1 separated from each
other at equal distances by short tubes D2 which may conveniently be also of
glass. The oscillator is connected up in circuit with electrical condensers E and
coils F having self-induction and is joined as by the wires G to the secondary
circuit of an induction coil H. This coil H with a small accumulator J and other
well-known accessories necessary for operating apparatus of this kind, may be
conveniently arranged within the casing A.
The receiving apparatus is contained within the lower casing A2 and comprises
two rods K mounted in one vertical line and having a coherer L placed in the
space between their adjacent ends. Condensers K¹ are placed at the other
extremities of the vertical rods K. The upper rod K is connected to an aerial
conductor K suspended from a mast K³ and the lower rod K is joined to earth
as at K, i.e., in the case of a ship to the framing of the ship or to the water.
The rods K are not always in contact with the poles of the coherer L; there
are spaces between them and in these spaces rotate discs L¹ of insulating material
which are provided (see Figure 3) with metallic pieces L³. When the metallic
pieces L² come between the ends of the rods K and the poles of the coherer, con-
nection is established, and the discs L' are so disposed relatively to the disc C³
'that the coherer is placed in and out of circuit alternately with the oscillator.
The discs L' are carried upon a shaft L3 which has a pinion L attached to its
upper end. This pinion is similar to the pinion C and gears with the wheel C³
which is carried by and rotates with the trunnion B³. The shaft L³ also carries
between the discs L' a toothed wheel M. The teeth of this wheel M catch the
end of a spring M₁ (Figure 4). This spring carries a small weight M² and as
the spring flies back the weight M2 taps against the coherer and causes it to de-
cohere. The metallic rods K are connected up in circuit with a primary battery
and with a relay N, and terminals O in connection with the relay are placed upon
the outside of the casing A2 and may be joined up to any convenient circuit
connected say with an electrically controlled steam whistle or other signalling
device.
Figure 5 is a diagram showing another arrangement according to this inven-
tion whereby the risk of actuating the receiver by waves from its own trans-
mitter is obviated. In this arrangement the rotating transmitter comprising
the parabolic reflector B and oscillator D is placed midway between two stationary
coherers L. These coherers L are joined in series and obviously the oscillator

page_text: can only influence one of them at a time. On the other hand waves coming from
an outside source would actuate both coherers and the receiving apparatus would
consequently operate.
It is obvious that apparatus according to this invention can be used for signal-
ling between a vessel and say a pier or other fixed point, its employment is not
restricted to signalling between two vessels.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
-
1. In signalling apparatus for preventing collisions at sea by means of Hert-
zian or similar waves the combination with a parabolic reflector rotatable about
a vertical axis of an oscillator in the focal line of the reflector in order to send
out a parallel bundle of Hertzian waves successively to all points of the horizon.
2. The combination of apparatus as claimed in Claim 1 with one or more
receiving devices and an acoustic signalling apparatus in order to know in the
described way the direction from whence the sound produced comes.
Tatal % 9741 1... of Wa 1000
THEODORE HERMAN HELENES BODDE.
Boult, Wade & Kilburn,
Agents for the Applicant.