Improvements in or connected with Electric Relays.
Year: 1894

page_text: Date of Application, 11th July, 1894
Complete Specification Left, 11th Apr., 1895-Accepted, 11th Sept., 1895
Improvements in or connected with Electric Relays.
A communication by CHARLES EUGENE MARECHAL, PIERRE CLAUDE HENRI
RIGOLLET, and the SOCIÉTÉ E. DUCRETET and L. LEJEUNE, all of 75 Rue
Claude Bernard, Paris, in the Republic of France, Electricians.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool, and 6, Bank Street
Manchester, both in the County of Lancaster and 323 High Holborn in the
County of Middlesex Civil Engineer, do hereby declare the nature of this
invention to be as follows --
The relay described in this application has for its object to serve for transmitting
any telegraphic or telephonic signals emitted both through aerial telegraph lines
and through subterranean and submarine cables.
According to the purposes to which it is to be applied, this apparatus is provided
with various independent devices capable of being added to or removed from the
principal apparatus. These independent devices allow, according to requirements,
the relay to be rendered more or less aperiodic, and to utilise the balistic effect
produced by the rush of the current, when it is precipitated into a conductor in order
to charge or discharge it.
On the other hand, owing to the sensitiveness of this relay being capable of being
rendered as great as possible, its applicability to telegraphic transmission over cables
of the greatest length will be readily seen. The slow and progressive variations of
the static condition of the conductor, such variations produced by the effects of
condensation, telluric currents, the residual charge, etcetera, etcetera, being unable to
affect it, the result is that this apparatus inay be considered as a very sensitive relay
with a practically fixed zero.
This relay is composed essentially of a freely movable coil H in a very intense
magnetic field (fixed), produced by permanent magnets C, C', or by electro-
magnets traversed by an auxiliary electric current. A central fixed piece F of iron
concentrates the lines of force. The whole may be of suitable form and dimensions,
and the same applies to the mode of suspension of the movable coil, and of the con-
struction of the frame which receives it, according to the degree of aperiodicity
which it is desired to obtain. It is also desired to retain the right of forming the
movable coil of a wire conductor of any suitable metal as may be found most
convenient, such as copper, silver, aluminium, various alloys, and the like.
In the same way, any suitable insulating or metallic substances may be employed
for the support of this movable coil, forming a freely movable frame. Such
substances may be cardboard, ebonite or the like, copper, silver, aluminium or the
like. The conducting wire forming this movable coil may be covered with a final
metallic casing, the effect of which will be added to that of the metallic frame in order
to obtain the maximum aperiodicity.
It is not desired to claim the right to these deails of construction, but it is desired
to point them out, describing them generally.
The accompanying drawing is shown as an example, the dimensions may be
variable.

page_text: On the movable coil H there is fixed a contact lever D, acting mechanically on
a system of parts, 1, V, b, enabling either the current to be broken between them, or
a variation of conductibility to be effected between them, or even the establishment
of a contact between them. The contact-lever D, therefore, follows all the move-
ments of the movable coil, and the mechanical effect which it produces upon the
external parts is obtained by the balistic effect of the movable coil H, as has been
already stated. This balistic effect may be maintained as reduced as necessary
within the limits of amplitude, in order to obtain the desired rapidity.
At the extremity of the contact lever D, there is a small magnet, one of the poles
of which is placed between those of two other independent magnet bars, the distance
apart of which (O) may be regulated by turning a regulating screw. These two
last bars, with their supports and their regulating pieces, constitute the first
arrangement, the so called "magnetic device M M," placed in front of the magnetic
field produced by C C'. Columns arranged for the purpose serve to receive these
various parts.
it
The three magnetic forces M. in the presence of one another, form a repelling
magnetic field, the action of which on the lever D is exerted equally well to right
and left, and maintain the latter in.a neutral position or in other words at zero ;
serves also for limiting the movement of the lever. if the intensity of the current
which traverses the movable coil H is too great. Further, if the static condition of
the conductor undergoes slow progressive or decreasing variations, which is generally
the case in submarine cables, variations which cause the movable receiving coil to
undergo a displacement more or less intense, the repelling magnetic forces oppose
themselves efficaciously to this displacement, and maintain by this means the lever
in its position at zero.
It is only under the action of a rapid variation of the potential, that the movable
circuit sets itself in motion and acts by its mass in the manner of a balistic galvano-
meter, with the sole difference, however, that. the lever D will return rapidly
to zero after the passage of the line current, because the curve which the movable
coil might describe remaining under the influence of the residual charge of the
conductor, is always compensated for by the action of the magnetic device M,. and
on the other hand, the striking of the lever D against the spring blade I causes a
return shock, which rapidly returns the lever backwards and therewith the frame
of the movable coil H connected with the lever D. The construction of this
frame ensures the suitable aperiodicity of the movable coil.
Two other independent suitably insulated devices placed opposite one another are
arranged on each side of the lever D, on supports prepared for the purpose. They
form the most important parts of this improved sensitive electric relay, and they
are essentially composed of a metallic spring blade II, closing the circuit of a local
battery by means of a contact vv (the ones marked I, I', ' can be dispensed
with in the case shown in the drawing); the receiver R R is arranged in the local
circuit. The pressure of the contact of I on is regulated, as desired, by means of
_regulating screws, and the same applies for bb, b¹ br.
The lever D of the movable circuit, which is placed between the two strips or
blades II at a little distance from these latter, will open the circuit on the right
if the direction of the line current causes the displacement of the coil fraine H
towards the right, or even will'open the circuit to the left if the line current is in
the opposite direction. The receivers of the local circuits will operate therefore
according to the so called continuous current system.
The purely mechanical action of the. lever D, instead of opening the circuit
at Ir, Iv, may also according to requirements close this circuit, it suffices to effect
..the inversion of the spring, blade I and of the contact piece by leaving a little
interval between these parts. A suitable regulation of these parts, produced by
means of suitable conducting materials, allows also of variations of pressure among
them, and consequently variations of the conductibility of the circuit to be obtained
and utilised..
The micrometric adjustments allow of each apparatus being approached to the

page_text: contact of the lever, in such a way as to increase or diminish the amplitude of the
vibrations of this latter, adding thus their own action to that of the magnetic
apparatus.
The contact screws bb have for their object, firstly, to limit the separation of
the spring blade I 1 and to give a definite duration to the interruption or the
closing of the local circuit, whatever may be the intensity of the line current,
and, consequently, of the displacement of the frame FL and its lever D, secondly, of
establishing a momentary connection of the line with the earth, in order to accelerate
the discharge from the side of the receiver.
The two
The accompanying figure shown as an example is that of an installation with two
of these improved relays coupled, working at the receiver, one under the action of.
the line current +, the other under the influence of the current
auxiliary relays R R are placed in local circuits, their armature is always in contact
by reason of the continuous current which passes through them, and which will be
broken at I v. As has been already stated, an inverse arrangement may be
employed. The relays R R act in their turn on a receiver S, which, in the case
shown on the drawing, is a siphon recorder S, but any suitable telegraphic apparatus,
the working of which is based on the use of currents of short duration such as the
Hughes, the two roller Morse or the like is also applicable.
The differential circuits are employed in the duplex transmission, they are at A A'
on the movable circuit frame H.
In the case shown in the drawing, the manipulator may be replaced by a
double key, or by any other suitable system of haud or automatic transmitting
apparatus.
A single relay may be employed. In the case where two relays are coupled, as
shown on the drawing, a contact apparatus remains at disposal 11. By a suitable
adjustment, this contact arrangement may be employed for the momentary
connection of the line with the earth, or for the emission of a discharge current
in the interval of two emissions, or for any other suitable combination of circuits.
If the double apparatus for interrupting or closing local circuits be replaced by
a microphonic system with variable contacts, on which system the contact lever (or
the frame itself or vice versa) rests, the differences of pressure in one direction or the
other will be observed in a telephone placed in the secondary circuit of an induction
coil in the manner of the ordinary microphones; the apparatus thus becomes a
telephone relay.
Dated this 10th day of July 1894.
A communication by CHARLES EUGENE MARECHAL, PIERRE CLAUDE HENRI
RIGOLLET, and the SOCIÉTÉ E. DUCKETET and L. LEJEUNE, all of 75 Rue
Claude Bernard, Paris, in the Republic of France, Electricians.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool and 6, Bank Street,
Manchester, both in the County of Lancaster, 118 New Street, Birmingham in
the County of Warwick and 31 High Holborn in the County of Middlesex, Civil:
Engineer, 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 :-
The relay described in this application has for its object to serve for receiving

page_text: and re-transmitting simple duplex or multiple telegraphic signals emitted both
through aërial telegraph lines and through subterranean and submarine cables.
According to the purposes to which it is to be applied, this apparatus is provided
with various independent devices, capable of being added to or removed from the
principal apparatus. These independent devices allow, according to requirements,
the relay to be rendered more or less aperiodic, and to utilise the balistic effect
produced by the rush of the current, when it is precipitated into a conductor in
order to charge or discharge it.
On the other hand, owing to the sensitiveness of this relay being capable of
being rendered as great as possible, its applicability to telegraphic transmission
over cables of the greatest length will be readily seen. The slow and progressive
variations of the static condition of the conductor, such variations produced by
the effects of condensation, earth currents, the residual charge, etcetera, etcetera,
being unable to affect it, the result is that this apparatus may be considered as
a very sensitive relay with a practically fixed zero.
The parts serving for the simple or duplex reception of any telegraphic signals
emitted under the ordinary conditions of aerial or submarine telegraphy will now
be described.
As shown in Figure I of the accompanying drawings, this relay is composed
essentially of a freely movable coil H in a very intense magnetic field (fixed),
produced by permanent magnets CC, or by electro-magnets traversed by an
auxiliary electric current. A fixed central piece F of iron concentrates the lines
of force. The whole may be of suitable form and dimensions, and the same applies
to the mode of suspension of the movable coil, and of the construction of the frame
which receives it, according to the degree of aperiodicity which it is desired to
obtain. It is also desired to retain the right of forming the movable coil of a
wire conductor of any suitable metal as may be found most convenient, such as
copper, silver, aluminium, various alloys, and the like.
In the same way, any suitable insulating or metallic substances may be employed
for the support of this movable coil, forming a freely movable frame. Such
substances may be cardboard, ebonite or the like, copper, silver, aluminium or the
like. The conducting wire forming this movable coil may be covered with a final
metallic casing, the effect of which will be added to that of the metallic frame in
order to obtain the maximum aperiodicity.
It is not desired to claim the right to these details of construction, but it is
desired to point them out, describing them generally.
The accompanying drawing is shown as an example, the dimensions may be
variable.
On the movable coil H there is fixed a contact lever D, acting mechanically
on a system of parts I V b, enabling either the current to be broken between them,
or a variation of conductibility to be effected between them, or even the
establishment of a contact between them. The contact-lever D, therefore, follows
all the movements of the movable coil, and the mechanical effect which it produces
upon the external parts is obtained by the balistic effect of the movable coil H,
as has been already stated. This balistic effect may be maintained as reduced as
necessary within the limits of amplitude, in order to obtain the desired rapidity.
At the extremity of the contact lever D, there is a small magnet, one of the poles
of which is placed between. those, of the same polarity, of two other independent
magnet bars, the distance apart of which (0) may be regulated by turning a
regulating screw. These two last bars, with their supports and their regulating
pieces, constitute the first arrangement, the so-called "magnetic device M" placed
in front of the magnetic field produced by C C¹. Columns arranged for the
purpose serve to receive these various parts.
The three magnetic forces M in the presence of one another, form a repelling
magnetic field, the action of which on the lever D is exerted equally well to
right and left, and maintain the latter in a neutral position, or in other words at
zero; it serves also for limiting the movement of the lever if the intensity of the

page_text: current which reverses the movable coil H is too great.. Further, if the static
condition of the conductor undergoes slow progressive or decreasing variations,
which is generally the case in submarine cables and subterranean lines, variations
which cause the movable receiving coil to undergo a slow displacement more or
less intense, the repelling magnetic forces oppose themselves efficaciously to this
displacement, and maintain by this means the lever in its position at zero.
It is only under the action of a rapid variation of the potential, that the movable
circuit sets itself in motion and acts by its mass in the manner of a balistic
galvanometer, with the sole difference, however, that the lever D will returu
rapidly to zero after the passage of the line current, because the curve which the
movable coil might describe remaining under the influence of the residual charge
of the conductor, is always compensated for by the action of the magnetic
device M, and on the other hand, the striking of the lever D against the spring
blade I causes a return shock, which rapidly returns the lever backwards and
therewith the frame of the movable coil H connected with the lever D. The
construction of this frame ensures the suitable aperiodicity of the movable coil.
Two independent suitably insulated devices are arranged opposite one another
on each side of the lever D, on supports prepared for the purpose. They form
the most important parts of this improved sensitive electric relay, and they are
essentially composed of a metallic spring blade I I' closing the circuit of a local
battery as shown in Figure 1, by means of a contact V V₁ (those marked I¹ V₁ can
be dispensed with in the case shown in the drawing). The receiver R R¹ is,
arranged in the local circuit. The pressure of the contact of I on V and I¹ on V₁
is regulated, as desired, by means of regulating screws and the contact screws bb
are also adjustable.
It may be observed here that the purely mechanical action of lever D on the
spring blades II' allows according to the purpose to which the apparatus is applied,
the greatest part of the combinations of coils known and utilized in telegraphy to
be obtained by the points of contact II, V V¹, 6 6 and those of the receivers R R¹
(polarized or otherwise), whether it be desired to open or close local circuits,
connecting the line momentarily with the ground in order to discharge it, or even
to send on the line one or more discharge currents in the interval of two signals, as
is shown in the accompanying drawings.
The lever D of the movable circuit, which is placed (see Figure 1) between the
two spring strips or blades I 11 at a little distance from these latter, will open the
local circuit on the right, if the direction of the line current causes the displacement
of the coil frame H towards the right, or even will open the circuit to the left if
the line current is in the opposite direction. The receivers of the local circuits
will operate therefore according to the so called closed circuit system. By
inverting the position of the contacts I, V, (I'V¹) and leaving a small gap between
them, the apparatus may be used to close instead of open the circuit.
The micrometric adjustments allow of each device being approached to the
contact of the lever in such a way as to increase or diminish the amplitude of the
vibrations of this latter, adding thus their own action to that of the magnetic
apparatus.
The contact screws bb¹ have for their object firstly, to limit the extent of
separation of the spring blades 1 1¹ from the contacts V V' under the action of
the lever D and to give a definite duration to the interruption or the closing of the
local circuit, whatever may be the intensity of the line current, and, consequently,
of the displacement of the coil H and its lever D; secondly, of establishing a
momentary connection of the line with the earth by Ib (or 16 when these are
used) in the interval of two contacts in order to accelerate the discharge of the line
from the side of the receiver.
The accompanying Figure 1, shown as an example is that of an installation
with two of these improved relays coupled, working at the receiver, one under
the action of the line current + the other under the influence of the current -,
that is to say that the two coils H undergo the same impulsion and swing both
"

page_text: in the same direction, but the useful effect of each lever D is only utilised in one
direction by connecting the local circuits with only one or other of the devices I VI
or 11 V1 61 of each relay according as required. The two auxiliary relays R R¹
are placed in local circuits, the armature of each is always down in contact by
reason of the continuous current which passes through their electro magnet, and
which may be broken at IV (I¹ V₁ not being in use in the case shown in Figure 1).
As has been already stated, an inverse arrangement may be employed, that is to
say the devices may be arranged and the connections made so as to close instead
of open the local circuits. The relays R R' act in their turn on a receiver S, which
in the case shown in Figure 1 of the drawings is a syphon recorder S, but any
suitable telegraphic apparatus, the working of which is based on the use of
currents of short duration such as the Hughes, the two roller Morse or the like,
is also applicable.
The differential circuits employed in duplex transmission, are at A A' on the
movable coil H.
In the case shown in the drawing, the manipulator may be replaced by a double
key, or by any other suitable system of hand or automatic transmitting apparatus.
A single relay may be employed. In the case where two relays are coupled,
as shown in Figure 1 of the drawings, the contact device I' VI of each relay
remains at liberty as before stated. Thus if an accident or an irregularity
occur, the apparatus may be changed at will without loss of time by simply
substituting V₁ for 6 I V, that is to say by changing the connections of the
wires from 6 IV to 6' 11 V1.
In Figure 2 the connections of the relays R, R¹ are arranged for transmitting
on the "
open circuit" system although no alteration is made in the contacts I, V
of relays 1 and 2. These relays are however adjusted so that the pressure of b
will keep I¹ in contact with lever D when the latter is in repose, thus serving as a
stop for this lever. When the key is up, the current from the line after leaving
the manipulator by the back contact arrives at the armature of the relay R, as
shown in the drawing, passes by the contact screw of this armature to the armature
of the second relay R³, then to 1 and V of relay 2 and to I and V of relay 1, iuto
the two coils, in order to pass to earth. At the moment, when according to the
direction of the line current the two levers tend to swing together to either one
side or the other, only one of the levers D is projected to the right or to the left
as motion of the other lever will be prevented by the stop formed by the
device I, V₁ as aforesaid; the swinging lever breaks the circuit of the
devices I, V, with the line, by separating I from V and pressing I against b, thus
placing the line in direct communication with one of the contact screws b which
will then close the circuit of one relay R or R' and of its battery P or P¹; the
current of oue or other of the local batteries P P¹ of the relays R K', find an issue
by band the line, will discharge the latter and also cause one of the relays R R¹
to act. Thus matters are arranged in such a way that if a + current comes from
the line, one of the local batteries P P of the relays R R' sends through ba
negative discharge into the line, and if the line current is a one, the other local
battery sends a + discharge.
-
Figure 1 shows an example of the connection of the line with the earth by b
and I after receiving each line current. Figure 2 represents the arrangements
adopted for sending discharge currents as stated. These details of local
installation are at the will of the operator.
A momentary contact by means of a flexible spring J places the line to the
ground by the manipulator during the transmission before and after the emission
of any current from the battery d.
་་
If the contact devices I, V, b, or 11 V₁of the lever D be placed in circuit
with a telephone receiver and with any source of electricity instead of in circuit
with the relays R R, and if there be inserted between the parts I V or 1 V₁ au
insertion of suitable conducting materials which vary in conductibility as the
pressure thereon varies, the contact lever bearing constantly on IV or 1 V1 will,

page_text: if vibrated by a line current in its coil, produce differences of conductibility in the
material between the contacts IV or IV₁ which will cause an undulating flow of
the current through the circuit connected to the said contacts I V or I¹ V¹, which
electric undulations will produce audible vibrations in said telephone.
Having now particularly described and ascertained the nature of the said inven-
Lion and in what manner the same is to be performed, as communicated to me by
ny foreign correspondents, I declare that what I claim is :-
The impovements in or connected with electric relays consisting in the con-
struction, transformation and applications such as herein before specified, of any
apparatus having a movable circuit in a magnetic field with arrangements enabling
the mechanical action of such movable circuit to be utilised for producing either
an interruption of a local current, or a variation in the conductibility, or the
establishment of a closing contact, the movement of said movable circuit only
intervening in order to utilise its ballistic action due to its own movement provoked
by the line current which passes through it substantially as hereinbefore described.
Dated this 10th day of April 1895.
WM. P. THOMPSON & Co.,
Agents.