Improvements in or relating to Telegraphic Receivers, especially applicable for Submarine Telegraphy.
Year: 1895

page_text: Date of Application, 29th Nov., 1895
Complete Specification Left, 26th Aug., 1896-Accepted, 31st Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in or relating to Telegraphic Receivers, especially
applicable for Submarine Telegraphy.
I, ALFRED PIEDFORT of Calais, in the Republic of France, Professor of
Sciences at the Pensionnat Saint Pierre do hereby declare the nature of this inven-
tion to be as follows:-
This invention relates to a new construction and arrangement of receiving
apparatus used in telegraphy especially on submarine lines; either for the purpose
of automatically tracing with clearness and precision upon telegraphic paper or
ribbon of the ordinary kind, the conventional signs corresponding to the sense of
the currents transmitted through the submarine cable, without aid from any other
Jocal electric current whatever; or in order to displace a sliding rod, accurately
determining with absolute certainty, no matter what may be the intensity of the
current bringing about such displacement-a contact capable of forming a relay
for a Morse or Hughes apparatus, or allowing the dispatch to be transmitted
further.
These results are obtained by the combination of a fine wire coil of a galvano-
meter, Thomson, D'Arsouval or other, with a mechanical multiplying device acting
on a lever, bearing either an ordinary syphon in case of an automatic registration
of the dispatches, without the aid of any local current; or a sliding rod of
restricted movement, which, by its contact forms a relay.
The multiplying device consists of one or two pieces of flexible wire or chain
wound several times round a rotary shaft, turning uniformly. The ends of each of
these wires or chains are connected, one with the fine-wire coil of the galvanometer,
either directly or by means of an intermediate lever and the other to a rod or lever,
carrying the syphon or the sliding rod.
The rotary shaft whereon the wires or chains are wound is set in motion by a
clcck-work train actuated by a spring or weight or by electricity.
The direction of rotation of the shaft is such that the latter tends constantly to
bring back the wires or chains towards the coil of the galvanometer.
Dated this 29th day of November 1895.
BOULT & WADE,
Agents for the Applicant.
Improvements in or relating to Telegraphic Receivers, especially
applicable for Submarine Telegraphy.
1, ALFRED PIEDFORT of Calais, in the Republic of France, Professor of
Sciences at the Pensionnat Saint Pierre, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This invention has for its object a new construction and arrangement of receiving.
apparatus used in submarine telegraphy, enabling either the conventional signš

page_text: corresponding to the sense of electric currents transmitted through the submarine
cable to be automatically traced with clearness and precision on ordinary telegraphic
paper, this being done without the help of any other local currents, or an oscillating
or sliding rod to be displaced with an absolute certainty whatever be the intensity
of the current producing said displacement, which oscillating rod produces a contact
capable of forming a relay for a Morse or Hughes apparatus or allows the dispatch
to be transmitted further.
These results are obtained by a combination of the coil of fine wire of the
galvanometer (Thomson's D'Arsonval or any other) with a mechanical multiplier
acting on a lever carrying either an ordinary syphon in case of an automatic
registering of dispatches without the aid of a local circuit or a rod with a limited
movement which by its contact forms a relay.
The multiplier consists of one or two threads or chains wound twice or several
times round a uniformly rotating spindle; one of the ends. of each of these threads
or chains is connected to the coil of fine-wire of the galvanometer either directly or
by means of a lever, and the other end of each of these threads or chains is attached
to a lever carrying the syphon or the oscillating rod. The rotating spindle on
which the threads or chains are wound is driven by a clockwork operated by a
spring, or weight or by an electric clockwork. The direction of the rotation of this
spindle is such that it always has the tendency to bring the threads or chains back
to the fine-wire coil of the galvanometer.
The accompanying drawings represent the combination of this multiplier with
the galvanometers usually employed in submarine telegraphy.
Figure 1 is an elevation and
Figure 2 is a plan, as seen from the top, of the whole arrangement of all the
parts of the improved receiver, when conventional signs corresponding to the sense
of the currents traversing submarine cable, are directly traced on paper P by a
syphon s. Figure 1 is a separate view showing the manner of suspending and
adjusting the fine-wire coil i.
Figures 3, 4 and 5 are respectively front-elevation, top-plan and side-view,
partially in section of the parts of the multiplying device and of the relay supported
by the table T of the improved receiver, showing the connection of this multiplier
with the fine-wire coil and with the different parts of the relay.
Figures 6 and 7 represent in elevation and plan the combination of my multiplying
device with a modified form of a Thomson mirror-galvanometer.
Like letters indicate like parts throughout the drawings.
This receiver is constituted as usually by a galvanometer G consisting of
magnetised bars A placed vertically and held at their upper ends in a pole-piece A¹;
and of a fine-wire coil i suspended vertically by the wires kk and j attached to
adjustable knobs secured to a bracket E placed between the north and south poles
of said magnet A.
A clockwork B (Figures 1 and 2) driven by a weight and spring, or electrically,
is placed near the galvanometer G. This clockwork regulated by a Hughes
governor R communicates to the spindle of the multiplying device uniform rotary
movement in the direction of the arrow 2. On the part of this spindle opposite the
fine-wire coil i pass two threads or chains g g winding round it several times.
One end of each of these threads or chains is attached to the corresponding
extremities of a balance-rod which is pivoted in its middle on a bracket m³
(Figure 5) at the same extremities of this balance-rod are secured silk fibre
threads 9 which are attached to the coil at equal distances from its axis of
suspension.
The other end of each of the threads or chains passes over a pulley n¹ which is
secured to a balance-rod n having equal arms and is attached to the end of a screw
threaded rod n' adjustable in length, fitted to the base of a small column n³
(Figures 3 and 5); the pulleys and the small columns 3 are mounted under the
balance-rod n at equal distances from its pivot o.
Spiral springs attached to the ends of the balance-rod n constantly tend to

page_text: Acep paramel to the rotating spinate 7; the tension of these springs o is regulated
by means of screw threaded rods 6' which are adjustably screwed into supports b
secured to the table T.
Under the balance-rod n and to the right and to the left of its pivot of is screwed
an aluminium plate provided with a long rod u³ (Figure 2) which is recessed in one
part of its length to receive the horizontal branch of a glass' syphon s. This rod u²
rubs near its free end on an ivory cross-piece which is vertically movable in a
base fixed to the edge of the table T; this cross-piece is raised or lowered by
turning a knob 2 (Figures 3 and 5) in which is screwed a screw threaded rod ¹ in
one piece with or secured to the cross-piece h. The more or less considerable
friction of the cross-piece h on the rod u² has for its purpose to diminish the inertia
of the coil.
The pivot of the balance-rod n (Figures 2 to 5) is insulated from the table T,
it carries under the balance-rod n an ebonite disc surmounted by a metal disc o
provided with a spring blade v¹; on the disc o rests a spring o' having the shape of
a Maltese cross, which is pressed against o by a nut 03 screwed on the screw-
threaded stem of the pivot; to the top of this screw-threaded stem or rod is
attached a lever v v³ the free end v2 of which is of soft iron; the end of the spring
blade is placed in a recess formed in the elbow part of the lever v.
Terminals are mounted on the edge of the table T near and at an equal
distance from the bent lever v; these terminals are each provided with screw-
threaded rods w³ w³ the corresponding points w w¹ of which are placed very close
to the lower part of the elbow of the lever v.
The slight inclinations of the coil i are transmitted by the silk threads g² and
their effect is increased by the chains g g¹ passing on the rotating spindle f; these
chains communicate said movements to the balance-rod n which oscillates round its
pivot o so that the recessed or grooved tube u² and the syphon carried by it as well
as the bent lever v repeat the slight inclinations of the coil i with an increased
force. The grooved tube thus moves the syphons which traces sinusoidal
curves on the paper P, said curves corresponding to the sense of the currents in
the cable. The bent lever v² in its movement meets one or the other of the points w
or w' of the relay in connection with a well known receiving apparatus M, such for
instance as Morse's or Hughes' receiver.
In order to obtain contacts on the lever vv it is provided with one end of soft
iron ² which moves opposite the north and south poles of a lever a having a horse
shoe or other convenient shape (Figures 3, 4, and 5). The distance of the poles a³
of this magnet a relatively to the opposite faces of the arm v² is regulated by means
of screws a².
The telegraphic paper P which is to receive the lines of ink taken by the syphon s
from an ink-pot u is supported on a slightly curved shelf c which is pivoted on a
pivot c* carried by a system of double carriage p' and 9' (Figures 1 to 5); one of these
carriages can be caused to move vertically by operating a knob q* and the
other pl making one piece with the preceding one, can be made to move horizontally
by turning a knob p³.
This double carriage p' q' carries the magnet a (Figures 3, 4 and 5), when the
shelf c is removed and the syphons is out of use.
By moving these carriages p' and q' it is easy either to bring the point of the
syphons against the paper P sliding over the shelf c or the magnet a in order to
bring its poles to a desired distance from the end of the lever v².
The fine-wire coil i is supported by the support E. which slides vertically in a
groove of a piece forming one piece with the blocks A' surrounding the poles of the
magnet A; it is suspended vertically by threads kk which pass over the pulley ³
(Figure 1A), the position of which can be regulated by moving the screw ;:other
threads passing through holes of the rods ³ enable the threads kk' to be
stretched. The lower part of the coil is held by the threads; which pass in the
hook of a spring forming one piece with a screw-threaded knob j. By suitably
operating the screws and k and; the nut j¹ the coil i is firmly held in a vertical

page_text: plane parallel to the horizontal axis of the spindle passing in the axis of the poles
of the magnet A. The threads 5, 6, 7, 8 of the coil i are respectively connected
to the terminals 5, 6, 7 and 8 which are connected to the cable and to the earth.
In the centre of the coil is arranged a block of soft iron fixed to the
support E.
The receiver works as follows:-
The clockwork B having been started, the spindle ŕ receives a uniform and
regular rotary movement in the direction of the arrows a so as to constantly bring
the threads or chains g 9', towards the coil ; these chains are thus stretched or
drawn in the direction of the arrows y.
As soon as a positive or negative current circulates in the submarine cable and
consequently in the coil i, the latter slightly moves in its vertical plane without
any strength in one or other direction (according to the sign of the current i.e.
positive or negative in the submarine cable) and exercises a very slight traction on
one or the other of the threads g² and on the chains g or g'; this very slight effort
is multiplied in consequence of the passage of the chain g or g¹ over the rotating
spindle so that said effort then becomes capable of moving the balance rod n and
the syphons or the bent lever v v2 which is in connection with the balance rod only
by the friction resulting from the pressure of the springs o' on the disc o.
The syphon s. being charged, traces to the right and to the left of the central
axis of the paper P sinusoidal curves s¹ which indicate the negative or positive
sense of the current and consequently the conventional telegraphic signs.
Or the elbow shaped part of the lever 2 meets one or the other of the
contacts wor w¹ of the terminals t or t' and forms a relay on an ordinary receiver M
which can transmit the telegram to a further station. The lever v participates in
the movement of the balance rod n in consequence of its frictional connection, but
as said lever meets, almost immediately the screw w or wl of the terminal t or t¹, it
immediately stops, closes a local circuit and leaves the balance rod n to continue
its movement alone. As soon as the balance rod n under the influence of the coil i
returns in the opposite direction, the lever v is caused to participate in its
movement and almost immediately strikes against the other screw w¹ or w. Owing
to the magnet a and to the spring vi attached to the elbow of the lever v, these
movements are very exact and take place always when the curve caused by the
current in the cable is lowered or raised the same amount.
I apply this multiplying device to any receiver or galvanometer of only sinall
power such for instance as Thompson's mirror-receiver in the manner illustrated
in Figs. 6 and 7.
This receiver is formed as usually of two pairs of coils I I' placed one above the
other; in the space between these two pairs of coils is vertically suspended by
means of one or two silk threads 8 a rigid aluminium rod to which is attached
opposite the hollow core of each coil a magnetised bar i¹ the north and south poles
of these bars are arranged in an inverted order so as to form an astatic system.
The vertical rigid rod is provided in its upper part with a balance rod and at
its lower part is suspended a weight Q. The one or several silk threads wind
round a shaft which enables the magnetic bars to be raised and to be brought
exactly opposite to the centre of the coils I I.
To the ends of the balance rod are attached silk threads g² which pass first
over the periphery of a smooth rotating cylinder f* then under the periphery of
another rotating identical cylinder f. Between the latter cylinder and the
rotating spindle the silk threads are attached to the threads or chains g g' which
are wound several times round said spindle and afterwards formed together and
passing over a light pulley n³, the position of which can be adjusted by the
screw n². The cylinders faud the shaft frotate in the direction of the arrows x
and in a uniform and regular manner under the impulse which they receive from
clockwork mechanism of which only the wheel B is here shown, and through the
intermediary of toothed wheels, B.
Under the horizontal end of the chain g is suspended an aluminium saddle s³

page_text: carrying an ordinary syphon s which dips on one side into an ink receptacle u while
its point comes in contact with the telegraphic paper P which unwinds over the
rollers c. In order to adjust the position of the saddle I suspend it on a part h¹
which can be moved in a straight line by a screw h².
As soon as the rigid rod 3 moves in one or other direction under the influence of
positive or negative currents passing through the coils II', the balance rod *
inclines in one or the other direction and produces traction upon the threads g';
said traction amplified by the passage of the threads and chains over the rotating
cylinders and over the rotating spindle f, is transmitted to the syphons the point.
of which traces to the right and to the left of the central axis of the paper P
sinusoidal lines s' corresponding to the sign of the currents which traverse the cable
or pass into the galvanometer.
may employ rotating cylinders f' in combination with the rotating spindle fin
the construction of the receiving apparatus illustrated in Figures 1 to 5. These
additional smooth cylinders permit the silk fibres g² to pass through them and thus.
make the apparatus still more sensitive.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what
claim is =
1. In a receiving apparatus for submarine telegraphs the combination with a
galvanometer of a multiplying device constituted by a rotating spindle fon which
are wound several times one or two threads or chains g g¹ each of which is attached
at one of its extremities directly or by means of an intermediate balance rod to.
the fine-wire coil of the galvanometer while the other extremity is secured to.
another balance rod n at an equal distance from its pivot o; said chains being
constantly drawn towards the coil i in consequence of the direction of the rotary
movement of the spindle f, or of the cylinders fand of the spindle f, so that that
part of each chain or thread which is attached to the coil is constantly floating in
order not to hinder the movements of the coil in its vertical plane of support..
The said balance rod n which receives the undulations of the coil being provided
with a rod u carrying a syphon s which traces directly on the telegraphic paper P
sinusoidal curves s corresponding to the movement of the coil, that is to say to the
negative or positive sign of the currents in the submarine cable, substantially as
described and illustrated in Figures 1 and 2.
v
2. In a receiving apparatus for submarine telegraphs constituted by the com-
bination of a galvanometer with a multiplying device formed by a rotating spindle, f
on which is wound several times one or two threads g g', the ends of which are
attached on one side to the coil i and on the other side to a balance-rod n which is
continually brought into position parallel to that of the spindle f by means of
springs the arrangement, on a pivot o of the balance-rod n of an oscillating
lever which is mounted so as to turn with a certain amount of friction on said
pivot o, and to be movable in front of the contact-screws w w³ which are in one
with the terminals t t of a relay connected to an ordinary receiver M (Morse or
Hughes); the soft-iron extremity v2 of said lever moving in front of the poles of
a magnet a which limits and regulates these movements; the movements of this
lever, which correspond to those of the coil i, enabling a relay to be actuated or
the telegram to be further transmitted; substantially as described and illustrated
in Figures 3, 4 and 5.
3. In a receiver or galvanometer of any system, producing a feeble action, the
combination with the galvanometer of a multiplying device constituted; either by
a rotating spindle on which one or two threads or chains 9 g' are wound several
times, said chains being connected to a rigid rod carrying magnetised bars i
which are suspended in front of the hollow cores of coils 11; or by a rotating
spindle and rotating smooth cylinders over which the threads or chains g g¹
connected to said rod 3 pass; the other extremity of each of these threads or
chains being connected to a syphons which accurately reproduces the movements

page_text: of the magnetic bars, and the point of which traces on the paper sinusoidal
curves & which correspond to the positive or negative sign of the currents in the
coils II of the galvanometer substantially as described and illustrated in
Figures 6 and 7.
Dated this 26th dow of A1000
BOULT & WADE,
Agents for the Applicant.