IMPROVED ELECTRICAL SIGNALLING APPARATUS, CHIEFLY DESIGNED FOR USE IN SHIPS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Geminiano Zanni at the Office of the
Commissioners of Patents on the 25th April 1878.
GEMINIANO ZANNI, of Highbury, in the County of Middlesex, Medical Electrician.
"IMPROVED ELECTRICAL SIGNALLING APPARATUS, CHIEFLY DESIGNED FOR USE IN
SHIPS."
This Invention relates to an improved signalling apparatus chiefly designed for
use on board ship as a means of communication between the captain or other person
in command, and the persons who have to obey his instructions, such for instance as
the individuals in charge of the engines or of the helm.
The said Invention is designed to provide such apparatus, so constructed that the
signals desired to be conveyed from one point to another shall be clear and unmistake-
able, without the liability to fail, which liability renders many appliances now in use
for the same purpose very unreliable, and consequently a source of danger at critical
times, when it is absolutely necessary that the signals should be promptly and
clearly understood by the person or persons who have to act according to the same.
According to the present Invention I make use of electricity, and I prefer that
the electricity for operating the apparatus should be generated by means of &
magneto-electric machine.
I am aware that magneto-electric apparatus have been heretofore employed for tho
same purpose,
but in such apparatus the current has been intermittent and a train
of clockwork or springs have been used in conjunction with electricity, such appa-
ratus have therefore been uncertain in their action, and have required considerable
attention in order to keep them in anything like an effective condition.
An apparatus constructed according to my said Invention operates by means of a
constant current, and I am enabled to dispense entirely with a train of clockwork
or springs, the whole of the required movements being effected by the direct action'
of the current of electricity.
In carrying the said Invention into practice I employ two electro-magnets the
poles of which are placed opposite to each other, and there is sufficient space between

page_text: them to provide for the reception of a movable armature which is placed in a vertical
position and works on a pivot, so that it may be alternately attracted to each
of the two magnets between which it is situated. To this armature 1 attach an
escapement device, verge, or pawl, securely fastened so that it may not be affected
by the motion of the ship, and which engages with the teeth of a ratchet wheel,
which is actuated and caused to rotate by the said escapement verge or pawl, the
latter receiving its movement owing to the motion of the armature between the two
magnets.
To the spindle of the said ratchet wheel an arm or pointer is fastened and a dial
plate is provided upon which the desired words or signals are printed or otherwise
applied. This dial may if desired be transparent and have a light placed behind it.
This instrument or apparatus, herein-after called the receiving instrument, is placed
in a convenient position to be easily seen by the person who has to take his instruc-
tions therefrom.
The apparatus for transmitting the desired signals to the said receiving instrument
is to be placed in a convenient position to be readily operated by the captain or other
person who has to use the same.
I prefer to construct this apparatus, herein-after termed the transmiting instrument,
as follows, that is to say I provide a compound magnet and revolving armature,
the latter of which may have one or more radiating coils, such as described in the
Specification of Letters Patent granted to me the 11th July, A.D. 1876, No. 2821, or
the apparatus may be constructed as described in the Specification of the Invention
for which Provisional Protection has been granted to me on my application, dated
the 13th day of November, A.D. 1877, No. 4232.
For the purposes of the present Invention I provide in combination with such a
magneto-electric apparatus two moveable arms or keys, so arranged that upon being
operated one of the same will cause the current to pass through one of the electro-
magnets in the said receiving instrument, and the other arm or key upon being
operated will send the current through the opposite electro-magnet. For operating
these arms or keys I form upon the upper and lower faces of a wheel, which is
provided in the magneto-electric apparatus aforesaid for operating the revolving
armature a series of projections, and I prefer to arrange these projections alternately
on the upper and lower faces of the said wheel near theedge thereof; I place the said
keys or arms in such a position that as the said wheel revolves the projections come
in contact with the said keys or arms, that is to say, the projections on the upper
face of the wheel will operate one of the said arms or keys, and the projections on the
lower face of the wheel will operate the other arm or key, so that as the wheel
revolves the two arms or keys will be operated alternately, and the current will be
caused to travel through the two electro-magnets of the receiving instrument alter-
nately, and thereby the pivotted armature aforesaid will oscillate between the two
magnets and operate the ratchet wheel carrying the pointer. A dial plate is placed
upon the said transmitting instrument corresponding with the one on the receiving
instrument, and I provide a crank or handle to be operated by the sender of the
signals, which crank or handle is attached to the spindle passing through the wheel
apon which are provided the aforesaid projections. By operating this handle the
sender generates the electricity, and by bringing the said handle over the work or
other signal desired to be transmitted the indicator on the dial of the receiving
instrument is caused to point to the same word or signal.
I connect the transmitting instrument with the receiving instrument by means of
three wires, one of which is connected with both of the said electro-magnets, the two
others being so arranged that one connects with one of the electro-magnets, and the
other with the other electro-inagnet. The current always passes through the first-
named wire, and alternately through each of the two others, that is to say, the first-
named wire is always a part of the circuit, and the two others are alternately in and
out of circuit, according as the said arms or keys are alternately operated. The
current thus passes first through one electro-magnet and then through the other, and

page_text: the pivotted armature is attracted alternately to one side and the other. This
arrangement effectually remedies the defect arising from the use of only one electro-
magnet in combination with a spring to operate the armature in one direction.
Another advantage is that the current is always travelling in the same direction,
instead of the polarity being changed as is the case when two wires only are used.
I connect a bell with the receiving instrument, and which will ring immediately
the transmitting instrument is operated, and thus attract the attention of the person
to whom the signals are to be transmitted.
I may also use two return wires so arranged that the signals transmitted by the
captain or other person sending the same will be repeated on the transmitting instru-
ment, thus enabling the sender of the signals to see that the same were shown
correctly on the receiving instrument.
Although I prefer to use a magneto-electric apparatus for generating the electricity
I may use a battery for the same purpose instead, in which case the transmitting
instrument would have to be modified accordingly; but the necessary modifica-
tion need not be described as it will be readily understood by electricians.
My said Invention will also be found very advantageous for transmitting signals
on railways, and otherwise than on board ship.