Improvements in Telephones and Telephonic Systems.
Year: 1897

page_text: Date of Application, 17th July, 1897-Accepted, 25th Sept.,
1897
COMPLETE SPECIFICATION.
Improvements in Telephones and Telephonic Systems.
We, FRANZ OPRENDEK of No. 7B Lehel utcza, Budapesth, in the Kingdom of
Hungary, Empire of Austria, Mechanician, and ARNOLD SÁRKÁNY of No. 16 Nador
uteza, Budapesth, in the Kingdom of Hungary, Empire of Austria, Manager, do
hereby declare the nature of our said invention and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement:
_
The present invention relates to improvements in telephones, according to
which the voice may be transmitted from the transmitter to one or more receivers
with unweakened intensity. This object is attained in part by the peculiar
circuiting employed and partly by the aid of transformers.
And in order to render the present specification more easily intelligible
reference is had to the accompanying drawings in which similar letters of reference
denote similar parts throughout the several views:-
Fig. 1 is a diagrammatical view of one form of carrying out the invention;
Figs. 2 and 3 are similar views of two forms of transformers which may be
employed,
Fig. 4 shows the arrangement of two loud speaking telephones with
transformers, and
Fig. 5 shows a further modification of the arrangement shown at Figure 4.
Referring first to Fig. 1, in the circuit of the battery B is arranged the
microphone M and the receivers are connected up in series. In the present case
the spools of the telephones T are differently wound to those hitherto employed,
in that the necessary Ampère windings are produced by a small number of coils
(40 to 100) and increased intensity of current. Consequently the thickness of
the wire is increased accordingly (0-12 to 0-5 mm) and the resistance of the spool
correspondingly decreased.
This arrangement enables a loud reproduction of the voice and is particularly
adapted for use in connection with railway trains and steamers, for calling the
names of the stations in the former case and for other communications in the
latter case.
The receivers in the former case would be arranged in the compart-
ments and the transmitter in the guards-van, whilst in the latter case the captain
would have the control of the transmitter. The device may also be employed in
connection with mining works or manufactories, as also for transmitting instru-
mental music songs and the like.
In the case of greater distances or of an increased number of receivers,
transformers are advantageously employed, two forms of which are illustrated in
Figures 2 and 3. The device illustrated in Figure 2 consists of a star shaped
oore having its ends closed together and being of magnetic metal, advantageously
soft iron wire. The core is provided with eight spools arranged in groups of
four each, said groups lying in two concentric circles. The primary wires p
are wound on the insulated core so as to encircle the same in several hundred

page_text: layers. The windings may be effected in various ways, thus one spool may be
completed before the next is begun or one spool may be provided with one or
more layers of coils, then the next with a similar number and so on to and i,
whereupon those of the inner set of cores are successively partially wound as at
25, 2, 27, 22. The next spool wound would then be ¹, the, operation being
repeated in a similar manner until the primary windings are completed, when the
secondary windings s are formed in exactly the same manner.
In the second form of transformer as illustrated in Figure 3, two rings of
magnetic metal (soft iron) are employed as at j', ja, said rings being connected
by arms, made of some suitable non-magnetic metal (copper, brass, zinc or the
like). These rings j, j are provided with suitable windings, the primary coils p
being first wound and then the secondary coils s. The primary coils may, as has
been already stated, be wound first on the ring and then on or j¹ may be
partially wound and then j² and so on. The secondary windings are effected in
a similar manner to the primary ones and may be insulated from the latter by
a strip of silk or the like.
Figure 4 shows the arrangement of two loud speaking telephone stations
rovided with transformers, each station having one primary circuit. The
battery B, microphone M and the primary coils of the transformer I are connected
up in series in the primary circuit. Both stations are connected by the secondary
circuit s', in which are arranged in series the secondary windings of both
transformers and the two electro-magnetic telephones T.
If, in the arrangement shown in Figure 1 the telephones T are replaced by the
primary windings of the transformers I, several receivers, arranged at considerable
distances may be served by one transmitter, if the said receivers are connected
to the secondary windings of the transformers. Several telephones may be
arranged in a secondary circuit as this will now be described in reference to
Figure 5. The arrangement just mentioned is not illustrated as it will be
self-evident to any one skilled in the art on reference to Figures 1 and 5.
Figure 5 shows a further development of the arrangements just described.
According to this development, several transformers I are arranged in the:
primary circuit of the microphone M and the battery B. The secondary spools
of these transformers form the secondary circuit in which the primary windings
of the transformers 12 are connected up in series. The secondary circuit s of the
transformers 12 form the tertiary circuit of the system, in which circuit the
telephones are arranged, or a further set of transformers, the secondary circuits of
which would form the quartic circuit of the system. In this manner the current
may be more and more distributed.
Experiments have shown that if single telephones T T2 etc., are arranged in
the primary, secondary, tertiary etc. circuits of the system, all the telephones will
reproduce the sounds transmitted much more clearly and loudly than when this
is not the case.
The arrangement described in connection with this specification have all been
shown as connected up in series, parallel connections may however be employed,
although the series connections give the better results.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
1. Loud speaking telephone, for transmitting sounds 'to one or more points,
characterized by the employment of telephones having electro-magnets with a
small number of coils of wire of increased thickness, and of transformers, one or
more having cores having their ends joined, said cores being of soft iron, the said
transformers being energized by the same conductors, the said transformers
being omitted in the case of short lines.
.:
2. In a telephone system comprising telephone magnets wound as specified,
and conductors, a transformer, consisting of, a soft iron wire bent to the form of a

page_text: star and adapted to form eight spools, two sets of four, each set lying in a
concentric circle substantially as described.
3. In a telephone system comprising telephone magnets wound as specified-
conductors, a transformer, consisting of two magnetic rings, advantageously of
soft iron, diamagnetical arms to connect said rings, and windings to said rings
arranged in series, substantially as described.
4. A telephone system consisting of a microphone, and microphone circuit and
a series of telephones having low resistance, connected up in series in said circuit.
5. In a telephone system the combination of a microphone circuit, a series of
transformers connected up in series therewith, the secondary circuit of one trans-
former being connected to the primary coils of another and a series of telephones
arranged as specified.
מנפTINT CTT
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicants.