Long Distance Telegraph Lines.
Year: 1886

page_text: Date of Application, 30th July, 1886.
Complete Left, 30th Apr., 1887.
Complete Accepted, 31st May, 1887.
other Long Distance Telegraph Lines.
1, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents,
do hereby declare the nature of this Invention to be as follows:―
This Invention relates to an improved transmitting instrument for submarine and
other long distance telegraph lines. The transmission of electrical impulses, as is well
known, is very much less rapid through subterranean or submarine cables than
through over-ground lines by reason of and in proportion to the electro-static
capacity of the cable, or in other words its power of condensation; the cause of the
retardation in the transmission of signals being due much less to the time necessary
to charge the cable which speedily attains a degree sufficient to actuate the receiving
instruments, than to the time necessary to discharge the cable, that is to say-for
its return to the neutral condition. To obviate the difficulty it is usual to make
use of a transmitter key which, after the passage of each current, puts the cable
to earth, so as to get rid of the residual charge of the cable. In lieu of this a
band of perforated paper has been caused to pass between two metallic rollers, the
current passing from the one to the other through the perforations whereby more
regular currents are emitted than by a hand worked instrument, there being two
series of perforations to each kind of signal, the one series corresponding to the
emissions of the charging current, and the other to those of the current in the
opposite direction for neutralizing the charge. The message must, therefore, be
prepared beforehand, by perforating the band of paper, and it is necessary to transmit
the whole message as thus prepared without the power of interruption in case of
unintelligibility.
This Invention consists in a new system of automatic distributor of the currents
necessary for transmission, which permits of retaining the ordinary mode of sending

page_text: and receiving with undiminished rapidity, whilst affording facility for interruption
and repetitition as may be required. The instrument consists of-1. An ordinary
double key worked by hand and having no other function than to determine, by
means of a local battery, the release of the distributing apparatus.-2. A current dis-
tributing apparatus, consisting, on the one hand, of a clock train actuated either by a
spring barrel, or other power, whereby a regular rotary motion is obtained for actuating
the distributor proper.
The distributor consists of a train of clockwork having continuous motion, the last
shaft of the train being governed by a fly, and rotating at a given speed, and carrying
eccentric or cam-like contact discs which are driven from the shaft by friction gear.
The contacts are normally held at rest by detents, but when one of them is released
by the action of a local current established by means of an ordinary key used as a
manipulator, one of the contacts is allowed to make a single revolution after which it
is again arrested. During the revolution it touches successively two contact springs
whereby, first, a working current is sent through the line, and afterwards a current
for neutralising the residual charge. The position of the contact springs is capable of
being so regulated as to give to the charge and discharge durations, proportional to
the capacity of the couple and adjustable according to its daily condition.
In order that the Invention may be more readily understood I have represented in
the accompanying drawings by way of example different views of a transmitting
apparatus constructed according to this Invention.
Figure 1 shows an elevation, and Figure 2 a plan of the apparatus. Figure 3 is a
section taken on line 1-2 Figure 1 drawn on an enlarged scale. In these figures
the same letters of reference indicate the same parts.
B
a is the base, and 6 the plates in which is mounted the clock train c provided with
a fly d for imparting a uniform rotary motion to shaft e upon which are keyed two
friction discs ff against which two other discs i loose on the shaft are pressed by
spring h, the loose discs being respectively in one with eccentric contacts k k of
platinum. The loose discs are each furnished with stop pins for engagement with
corresponding detents for preventing their rotation by the discs f. The detents P
are carried by the armatures of two electro magnets mm² whose operation will be
described hereafter. Upon an insulating support n are mounted four springs op
and o'p', connected diagonally by conductors r.'s as shewn in figure 3 connecting the
supporting brackets ut and u¹t. The brackets tt supporting the lower ones of each
pair of springs, are connected, the one to the right of the positive pole of a battery of
which the negative pole is to earth, and that on the left to the negative pole of another
battery the positive pole of which is to earth. The contacts k k¹ communicate with the
line through the shaft e.
The operation of the apparatus is as follows; By means of a local battery and an
ordinary double key, a current is sent through the terminal 1 and the terminals 2
or 3, through the one or other electro-magnet m or m¹. Suppose the current to
be sent through m the armature lever of that magnet is attracted, and the loose
friction disc i and corresponding contact k released. The disc i is then rotated by
frictional contact with the corresponding friction disc and its contact k being
carried round with it, comes in contact first with the lower spring o and then with the
upper spring p. By this action a negative current from the first battery is sent
through the line through the wire-x, bracket t, spring o, contact k, and shafte and
after a short interval when the contact & has quitted spring o and touched spring p, a
positive current from the second battery is sent through the line by the wire y,
conductor bracket u, spring p, contact k and shaft e. This second current being in
the opposite direction to the first, has for its object to return the line to a neutral
condition before the emission of another current for producing the next signal of the
message. If the local current is sent through the other electro-magnet m¹ the
operation is similar, but the poles of the line battery are put to line by the contact k¹
in the inverse direction, that is to say, the line instead of receiving first a negative
current and then a positive current which neutralises the charge of the first, receives
first a positive current and then a negative current.

page_text: In each case the contact after performing a complete revolution, is again arrested
by the corresponding armature lever and cannot again rotate without a fresh current
being sent through the electro-magnet.
It will be understood that in order to effect the neutralisation of the charge in the
line by the second current which follows the signalling or working current, it is
necessary that the passage of these two successive currents should take place during
predetermined periods, the relative durations of which must be regulated according to
the conditions in which the line is placed. In order to permit of this regulation the
springs op, op' and their support n may be shifted relatively to the contacts k³, the
support n being for this purpose mounted on a bracket v pivoted on a centre eccentric
to the shafte and provided with a toothed segment w gearing with a tangent screw z
by which the springs op, o¹ pl are, adjusted relatively to the contacts kk' in such a
manner as to vary the duration of the contact springs with these eccentrics. The centre
about which this adjustment is effected is coincident with the centre of the eccentric
contact k k¹.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in Transmitting Instruments for Submarine and other
Long Distance Telegraph Lines.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents,
do hereby declare the nature of this Invention (a communication to me from abroad
by Louis Maiche of Paris, France), 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 an improved transmitting instrument for submarine and
other long distance telegraph lines. The transmission of electrical impulses, as is well
known, is very much less rapid through subterranean or submarine cables than
through over-ground lines by reason of and in proportion to the electro-static capacity
of the cable, or in other words its power of condensation, the cause of the retardation
in the transmission of signals being due much less to the time necessary to charge
the cable which speedily attains a degree sufficient to actuate the receiving instru-
ments, than to the time necessary to discharge the cable, that is to say for its
return to the neutral condition. To obviate the difficulty it is usual to make use
of a transmitter key which, after the passage of each current, puts the cable to
earth, so as to get rid of the residual charge of the cable. In lieu of this a band of
perforated paper has been caused to pass between two metallic rollers, the current
passing from the one to the other through the perforations, whereby more regular
currents are emitted than by a hand worked instrument, there being two series of
perforations to each kind of signal, the one series corresponding to the emissions of
the charging current, and the other to those of the current in the opposite direction
for neutralizing the charge. The message must, therefore, be prepared beforehand, by
perforating the band of paper, and it is necessary to transmit the whole message as
thus prepared without the power of interruption in case of unintelligibility.
This Invention consists in a new system of automatic distributor of the currents
necessary for transmission, which permits of retaining the ordinary mode of sending
and receiving with undiminished rapidity, whilst affording facility for interruption
and repetitition as may be required. The instrument consists of-1. An ordinary
double key worked by hand and having no other function than to determine, by
means of a local battery, the release of the distributing apparatus.-2. A current
distributing apparatus, consisting, on the one hand, of a clock train actuated either by
a spring barrel, or other power, whereby a regular rotary motion is obtained for
actuating the distributor proper.
The distributor consists of a train of clockwork having continuous motion, the last
shaft of the train being governed by a fly, and rotating at a given speed, and
carrying eccentric or cam-like contact discs which are driven from the shaft by
friction gear.

page_text: The contacts are normally held at rest by detents, but when one of them is released
by the action of a local current established by means of an ordinary key used as a
manipulator, one of the contacts is allowed to make a single revolution after which it
is again arrested. During the revolution it touches successively two contact springs
whereby, first, a working current is sent through the line, and afterwards a current
for neutralising the residual charge. The position of the contact springs is capable of
being so regulated as to give to the charge and discharge durations, proportional to
the capacity of the couple and adjustable according to its daily condition.
In order that the Invention may be more readily understood I have represented in
the accompanying drawings by way of example different views of a transmitting
apparatus constructed according to this Invention.
Figure 1 shows an elevation, and Figure 2 a plan of the apparatus. Figure 3 is a
section taken on line 1-2 Figure 1 drawn on an enlarged scale. In these figures
the same letters of reference indicate the same parts.
a is the base, and 6 the plates in which is mounted the clock train c provided
with a fly d for imparting a uniform rotary motion to shafte upon which are
keyed two friction discs ff against which two other discs i loose on the shaft
are pressed by a spring , the loose discs being respectively in one with eccentric
contacts k k of platinum. The loose discs are each furnished with stop pins for
engagement with corresponding detents 11 for preventing their rotation by the
discs. The detents are carried by the armatures of two electro magnets mm²
whose operation will be described hereafter. Upon an insulating support ? are
mounted four springs op and o'p¹, connected diagonally by conductors r. s as shewn
in figure 3 connecting the supporting brackets, ut¹ and u¹t. The brackets & t¹
supporting the lower ones of each pair of springs, are connected, the one to the right
of the positive pole of a battery of which the negative pole is to earth, and that on
the left to the negative pole of another battery the positive pole of which is to earth.
The contacts k k¹ communicate with the line through the shaft e.
The operation of the apparatus is as follows; By means of a local battery and an
ordinary double key, a current is sent through the terminal 1 and the terminals 2 or 3,
through the one or other electro-magnet m or m¹. Suppose the current to be sent
through m the armature lever I of that magnet is attracted, and the loose friction
disc i and corresponding contact k released. The disc i is then rotated by frictional
contact with the corresponding friction disc fand its contact & being carried round
with it, comes in contact first with the lower spring o and then with the upper
spring p. By this action a negative current from the first battery is sent through the
line through the wire x, bracket t, spring o, contact k, and shaft e and after a
short interval when the contact k has quitted spring and touched spring p, a
positive current from the second battery is sent through the line by the wire y, con-
ductor bracket u, spring p, contact k and shaft e. This second current being in the
opposite direction to the first, has for its object to return the line to a neutral
condition before the emission of another current for producing the next signal of the
message. If the local current is sent through the other electro-magnet m' the
operation is similar, but the poles of the line battery are put to line by the contact k¹
in the inverse direction, that is to say, the line instead of receiving first a negative
current and then a positive current which neutralises the charge of the first, receives
first a positive current and then a negative current.
In each case the contact after performing a complete revolution, is again arrested
by the corresponding armature lever and cannot again rotate without a fresh current
being sent through the electro-magnet.
It will be understood that in order to effect the neutralisation of the charge in the
line by the second current which follows the signalling or working current, it. is
necessary that the passage of these two successive currents should take place during
predetermined periods, the relative durations of which must be regulated according
to the conditions in which the line is placed. In order to permit of this regulation
the springs op, op' and their support n may be shifted relatively to the contacts k¹,
the support n being for this purpose mounted on a bracket pivoted on a centre

page_text: eccentric to the shaft e and provided with a toothed segment w gearing with a
tangent screw z by which the springs op, op¹ are adjusted relatively to the
contacts kk¹ in such a manner as to vary the duration of the contact springs with
these eccentrics. The centre about which this adjustment is effected is coincident with
the centre of the eccentric contact, k k¹.
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-
The herein described system of transmitting instrument whereby currents of
alternately opposite polarity are automatically distributed to telegraphic lines, the
instrument consisting essentially in a combination with a motor mechanisin having a
uniform motion, of a combination of contacts actuated by friction gear and controlled
by the armatures of electro-magnets energised by the action of a local current
substantially as specified.