Improvements in and relating to Telephone-installations.
Year: 1898

page_text: Date of Application, 14th May, 1898
Improvements in and relating to Telephone-installations.
I, EDOUARD BAIVY, of 35, Rue de Lesbroussart, Brussels, in the Kingdom
of Belgium, Engineer, do hereby declare the nature of this invention to be as
follows:
This invention relates to a special system of connecting automatic indicators
with always two electro magnets and two armatures, the characteristic feature
being, that the said indicators admit of being connected with the loop or shunt
circuit either in parallel or in series as desired-in such a manner, that with-
out the requirement of relays and local currents, the one or the other, or both
of the electro magnets, simultaneously, can be energized, namely so, that the
current, passed through one of the electro magnets will release the flap, whereas
the current sent through the other electro magnet will throw the flap into engage-
ment and will retain the same in its resting position, in which the same is, more-
over not acted upon, when the current traverses both of the electromagnets,
whereas, in the latter case, the current has the effect of re-engaging the flap
should the same have been previously disengaged.
These various connections of the electro magnets and the effects, corresponding
to such connections are obtained, without the aid of relay-currents by joining
the two electro magnets of the indicators on the one hand, to the line and con-
necting them on the other hand, to carth, whereby the subscribers as well as the
employees of the central station are enabled through the intermediary of the
contact pieces at their disposal, to form electric circuits, which, acording to re-
quirement, include either one or the other of the electro magnets or both simul-
taneously, and actuate the flaps in a suitable manner.
For further explanation reference is made to the accompanying drawing, in
which
Figures 1, 2, 3 represent diagrammatically the connection, whereas in Figure 4
an indicator with two electro-magnets and two armatures is represented by way
of example.
A and B are the two electro magnets, the magnetic effects of which are
neutralized in the centre by the common pole-plate C.
The electro magnet A operates by its acting pole upon an armature a, adapted
to oscillate in the ordinary manner at o, this armature being provided with the
lever . The active pole for B is curved, and the armature b, purved in con-
formity therewith, oscillates together with the flap fixed thereto, upon the
point o
As long as the indicator is without a current, the flap bears against the end
of the lever and covers the number indicating the subscriber.
If a current is sent through A and the armature is thereby attracted, the
lever rises and releases the flap, during which operation the armature b is
drawn down by its own weight and the flap, while uncovering the number, is
placed in a horizontal position.
If now the current in A again ceases and a current, he sent through B, the

page_text: armature 6 of the latter is attracted and consequently the flap. slightly lifted
by the lever 1, is again thrown into engagement. The engaging operation like-
wise takes place, when the current traverses the electro magnets, whereby the
two armatures are simultaneously actuated, the result of which is, that under
these conditions the flap is not released when in resting position.
The exclusive use of the circuits produced by the conductor, and required for
the purpose of executing these operations does not give rise to any complications
upon the installation, on the contrary extremely simple multiple-flat-clicks or
latches may be used without the current being interrupted, the said clicks or
latches having but two points of contact with the plugs, namely the socket c and
the spring, which are in direct connection with the conducting wires, from
which the advantage results, that also the windings of the electro-magnets of
the indicators can on the one hand be directly connected to the conducting wires
and, on the other hand, be connected to earth, as is represented in Figure 1.
For the purpose of further illustrating the operations, Figure
may be referred
to, supposing, however, that the subscriber's posts not represented therein, are
so arranged, that the subscriber can, at will send a current over the one or the
other wire of the loop- or shunt circuit.
For the purpose of calling the central station, the subscriber then passes a
current through the wire L', which consequently traverses the electro-magnet A
and goes to earth and in so doing releases the flap. Thereupon the employee
inserts the plug f into a click or pawl, corresponding to the caller's flap and in-
cludes his apparatus P in the circuit thus produced, so as to enable the caller to
communicate. In order to examine the required connection the official places
the point of the plug f in contact with the socket of one of the corresponding
clicks or pawls, and thus ascertains, whether the line is unoccupied, in which
case his telephone does not sound, owing to the fact that the circuit to be
examined has no current and that consequently the plug does not convey a branch
or shunt current. If, on the contrary the line be occupied, a current shunted
from the battery ? or (according as the circuit is closed by another pair of
plugs upon the telephone P or upon the closing-flap A¹ B' of the corresponding
switch-board) passes through the employees telephone P.
"
If the line be unoccupied the employee inserts the plug f¹, closes the circuit
of the called subscriber, and simultaneously informs the caller by the word
ring," while disconnecting at the same time his telephone P and connecting,
in its place, the closing flap A B¹. The caller then sends the current over the
loop- or shunt circuit L L¹ and thereby actuates the bell of the subscriber to
be called. During this operation the current passes through the two electro
magnets of the two call-flaps A B, inserted in the circuit, as well as through
the closing-flap A B, whereby the flap of the calling subscriber is thrown into
engagement, whilst the two other flaps are not being acted upon and all the other
parts remain during the communication in their position of rest.
In order to give the clear out signal, the subscriber sends the current over
the wire L, thus connecting the circuit to earth, so that the current passes
through the electro magnets B of the call-flaps thereby leaving them unactuated,
whereas the same current, on the contrary, flows through the electro magnet A¹
of the closing-flap and releases the same, thus indicating the close of the com-
munication. The employee then withdraws the plug, and re-engages the closing-
flap by closing the current prs, traversing the electro-magnet B.
Although, as already stated, this arrangement admits of using the simple
multiple-flat-clicks or pawls, without breakage of current, with only two contacts
for the plugs, it is also possible, that in this arrangement more complicated
clicks or pawls, such for example as local clicks or pawls with breakage of current
may be employed for disconnecting the call-flap from the circuit. All that is
necessary for this purpose, is, to arrange the connections, as illustrated in
Figure 2.
Moreover the battery p, instead of being joined to the centre of the two electro

page_text: magnets may also be connected to one of them A', provided that the electro
magnet B has also been connected to earth.
The indicators may, of course, be likewise of any suitable construction, pro-
vided that the conditions mentioned are duly adhered to.
It may be mentioned in conclusion, that by this arrangement the activity of
the officiating employees is very considerably lessened and is almost entirely
reduced to inserting and withdrawing the plugs.
141
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, N.C.,
Agents for the Applicant.
Improvements in and relating to Telephone-installations.
I, EDOUARD BAIVY, of 35, Rue de Lesbroussart, Brussels, in the Kingdom
of Belgium, 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; —
This invention relates to a special system of connecting automatic indicators
always with two electro magnets and two armatures, the characteristic feature
being, that the said indicators admit of being connected with the loop or shunt
circuit either in parallel or in series, as desired-in such a manner, that without
the requirement of relays and local currents, the one or the other, or both of
the electro magnets simultaneously, can be energized, in such a manner that the
current, passed through one of the electro magnets will release the flap, whereas
the current sent through the other electro magnet will throw the flap into engage-
ment and will retain the same in its resting position, the same being, moreover,
not acted upon, when the current traverses both of the electromagnets, but has
the effect of fully re-engaging the flap should the same have been left slightly
disengaged.
These various connections of the electro magnets and the effects, corresponding
to such connections are obtained, without the aid of relay-currents, by joining
the two electro magnets of the indicators, on the one hand, to the line and con-
necting them on the other hand, to earth, whereby the subscribers, as well as the
employes of the central station are enabled through the intermediary of the
contact-pieces at their disposal, to form electric circuits, which, according to
requirement, include either one or the other of the electro magnets or both
simultaneously, and actuate the flaps in a suitable manner.
For further explanation reference is made to the accompanying drawings, in
which:
Figure 1 is a diagram of the improved arrangement with simple jacks for
two contacts with the peg or plug and without contact brakes.
Figure shows a similar arrangement with jacks having two contact brakes.
Figure 3 is a modification in the method of connecting to earth the two con-
volutions of the annunciator, and
Figure 4 an indicator with two electro-magnets and two armatures.
A and B are the two electro magnets, the magnetic effects of which are
neutralized in the centre by the common pole-plate C.
The electro magnet A operates by its acting pole upon an armature a, Fig. 4,
adapted to oscillate in the ordinary manner at o, this armature being provided

page_text: with the lever 1. The active pole for B is curved, and the armature b, curved
in conformity therewith, oscillates together with the flap v fixed thereto, upon the
point o¹.
As long as the indicator is without current, the flap bears against the end of
the lever and covers the number indicating the subscriber.
If a current is sent through A and the armature a is thereby attracted, the
lever rises and releases the flap, during which operation the armature bis
drawn down by its own weight and the flap e, while uncovering the number, is
placed in a horizontal position.
If now the current in A again ceases and a current be sent through B, the
armature of the latter is attracted and consequently the flap by slightly
lifting the lever 1, is again thrown into engagement. The engaging operation
likewise takes place when the current traverses both electro magnets, whereby
their two armatures are simultaneously actuated, the result of which is, that the
flap, when in its normal or idle position is not released.
The exclusive use of the circuits from the conductor, required for the purpose
of these operations does not give rise to any complications upon the installation.
on the contrary extremely simple multiple clicks latches or flaps may be used
without the current being interrupted, the said clicks, latches or flaps having
but two points of contact with the plugs, namely the socket c and the spring b
which are in direct connection with the conducting wires, from which the advan-
tage results, that also the windings of the electro-magnets of the indicators can
be directly connected to the main conducting wires and to earth, as is repre
sented in Figure 1.
For the purpose of further illustrating the operations, Figure 1 may be
referred to, it being supposed however, that the subscribers posts not represented
therein, are so arranged, that the subscriber can, at will send a current over the
one or the other wire of the loop or shunt circuit.
In order to call up the central station the subscriber by the proper means with
which he is supplied at his station, sends a current through the wire L' thence
through the electromagnet A of the annunciator to earth thereby disengaging
the disc or shutter to attract the attention of the attendant at the central
station, who thereupon inserts the peg or plug f, which is provided with two con-
tacts, into one of the jacks b c corresponding to the annunciator which has been
disengaged and who thereby closes the circuit L L' including the microphone
of the subscriber which this latter has in the meantime connected in circuit by
removing his receiver from the hook for the purpose of listening. The first
effect of this is that the annunciator disc is re-engaged through the current of
the battery of the microphone passing through the two convolutions A and B
thereby replacing the disc as stated. The attendant now connects or inserts his
station in the circuit by the ordinary key so as to enable the message to be
received.
In order to ascertain whether the line is open the attendant touches with the
point of the peg f¹ the solid part of one of the jacks corresponding to the line of
the subscriber enquired for listens whether he can hear anything, that is to say
whether there is a current passing through the line, or in other words whether
the line is not connected with the battery 2, no current should be taken up by
the peg or plug f' and transmitted to the telephone so that the latter should remain
silent. If however the line be occupied and connected up with the battery p
or according to the position of the key which interpolates or inserts the tele-
phone or the clearing out annunciator, the plug f by being brought into con-
tact with one of the jacks which forms part of the engaged circuit, derives a
current from either or ¹ which passes into the telephone of the attendant
who will be able to hear the noise caused thereby from which he will understand
that the line is engaged.
If the line be found disengaged the attendant places the plug f¹ into the jack
of the subscriber to be called up and thereby connects the line of this subscriber

page_text: with that of the "caller" whom he then informs by the word " ring" that he
is connected up. At the same time the attendant displaces his key so as to
cut out his own telephone P from this circuit and interpolates the annunciator
of the end of the line A¹ B'.
The caller then places his receiver on the hook and thereby connects at once
in the same circuit L L the two hells, the two call annunciators A and B and
the annunciators A¹ B' at the end of the line of the two subscribers and in this
manner the current passing through this circuit passes through the two coils of
each of these annunciators without however affecting them which is proved by
the discs or shutters remaining engaged from which it follows that the two sub-
scribers may without fear operate their bells or answer back without interfering
with anything at the central office.
By now taking the receivers off the hooks the microphones are interpolated
and they are then able to converse together.
In order to give the clearing out signal, the subscriber sends the current over
the wire L, thus connecting the circuit to earth, so that the current passes through
the electromagnets B of the call-flaps thereby leaving them unactuated, while
the same current, flows through the electro magnet A¹ of the closing-flap and
releases the same, thus indicating the close of the communication. The employe
then withdraws the plug and re-engages the closing-flap by closing the current
prs, traversing the electro-magnet B.
Although, as already stated, this arrangement admits of using the simple
multiple clicks or flaps, without breakage of current, with only two contacts for
the plugs, it is also possible, that in this arrangement more complicated clicks
or flaps, such for example as local clicks or flaps with breakage of current may be
employed for disconnecting the call-flap from the circuit.
All that is necessary
for this purpose, is, to arrange the connections, as illustrated in Figure 2.
In the modification shown in Figure 2 the coils A and B are normally inter-
polated in the circuit L L by means of the contacts a and b so that the disc or
shutter falls when the subscriber sends current through L' as before. If then
the attendant introduces the plugs f f establishing the circuit L L' he cuts
out the contacts a and b and places the annunciators out of circuit and thereby
enables the subscribers to ring without affecting the same as hereinbefore, but
at the same time he establishes the contacts between 1 and thus sending a
current through the electro-magnets B which re-engage the discs or shutters;
all the rest of these operations being the same as before.
Again it is not indispensable to connect the two coils A¹ B' of the annunciator
to earth, at the end of the line, by the common wire leading to the battery p.
As shown in Figure 3 the battery need only be connected to the electro
magnet A if the other electro magnet B' be connected to earth by a second
wire, because then the arrangement works in the same manner as before stated
upon the attendant having interpolated the annunciator A B in the line L L'
by the aid of his ordinary key; with the only difference however that an
auxiliary battery 23 must be interpolated in the circuit Br, s to provide for
the re-engaging of the flap or shutter at the end of the line.
The indicators may, of course, be likewise of any suitable construction, pro-
vided that the conditions mentioned are duly adhered to.
It may be mentioned in conclusion, that by this arrangement the work of the
officiating employes is very considerably lessened and is almost entirely reduced
to inserting and withdrawing the plugs.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
A telephone-installation for loop or shunt circuits with automatic indicators
having two electro magnets and two armatures, the characteristic feature consist-
ing in the special connection of the indicators within the circuit in such a manner,

page_text: that the windings of the one electro magnet are connected with one wire of the
circuit, and the windings of the other electro magnet are connected with the
other wire of the circuit, whilst both said windings are, connected to earth, for
the purpose of energizing, at will, either one or the other or both of the electro
magnets by the main current without the aid of relays and local currents.
Tatl
dar of T
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.