DE223977C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- M 223977 CLASS 21 a. GROUP

SIEMENS & HALSKE AKT-GES. in Berlin.

Patented in the German Empire on February 9, 1909.

The invention relates to telephone exchanges whose plug wires do not have a supply current for the subscriber microphones, and relates to a circuit arrangement for call counters in such offices that count when reporting the called subscriber. In the circuits that have become known this The type of current change that occurs when the participant is reported is the third

ίο plug-in charger (c-wire) to initiate the counting used; aids are necessary for an early count when sending prevent the ringing current.

The counting is now initiated by a relay connected to one or both speech wires the plug line and the call relay of the requested subscriber in parallel is switched. According to the invention, this relay switches on when the called party is reported Participant automatically from the speech line and into the meter circuit.

The drawing shows an embodiment of the invention.

In the case shown, the counting takes place via a special wire d of the interrogation plug AS, which is inserted into the interrogation pawl AK _{1 of} the calling subscriber T ₁ . The counter Z connected to the battery B initially receives no power because the wire d is interrupted at a contact e.

If the requested subscriber T ₂ , after being queried in the usual way and the connection is made via the jack VK ₂ , reports by lifting his handset, a relay R, which is connected to the δ wire of the connecting plug and by plugging in the Plug of the δ-winding of the call relay AR _{2 of} the subscriber T ₂ is connected in parallel, brought to response by a part of the subscriber's microphone feed. As a result, it attracts its armature f and closes contact e. After closing e , contact g is opened, so that relay R is disconnected from the voice line.

Through the armature f and the contact β , the circuit of the counter Z, through the winding of the relay R, is completed, so that the counting takes place. The circuit remains closed until the AS interrogation plug is pulled; Both the counter and the relay R therefore remain constantly energized, so that double counting is excluded.

Instead of connecting the relay R directly to the δ wire of the connecting plug, it can be connected via a contact h of the speech switch (indicated by a cross in the drawing), which is open in the interrogation position of this switch. A switch armature can also be arranged at h, which is triggered by a relay that only responds when the connection plug is inserted, the z. B.

Claims (1)

is in the c-core of the plug, depends. In both cases, any current surges when inserting the plug VS can be rendered ineffective. The arrangement can also be made so that the relay R remains permanently on the line. As far as it seems appropriate to take into account the symmetry of the speech lines and the like, it can also apply to both ίο speech cores are laid. The relay can also switch on other devices that should also come into action when the subscriber is reported, and one of these devices, after it has been activated, can only switch off the relay R in order to keep the meter and the other devices working as safe as possible. In certain conversations, e.g. B. if the subscriber T ₁ requires connection with a service point D , a count should not take place. According to the invention, the excitation of the relay R is prevented for such connections by a capacitor i which, in the case of the example, is placed in the δ line of the pawls K of such services D and does not allow a direct current flow to the relay R. In the case of a connection via an exchange connection line, the count also only takes place when the second participant reports, as is the case with a direct connection. If the connection plug VS is plugged into the jack VKl of an outgoing connection line, the relay R is connected via the δ wire to the monitoring relay UR of the line, which is switched in the usual way, that the same current conditions are produced by its excitation as with a direct connection with a participant. Sponsorship τ claim: Circuit for call counters in telephone exchanges whose plug wires do not carry a feed current for the subscriber microphones, and in which to the speech lines (a, b) of the pair of plugs (AS, VS), in parallel to the call relay (AR ₂ ) of the requested subscriber (T ₂ ) a relay (R) dependent on this is switched, characterized in that this relay (R) is automatically disconnected from the speech line (a, b) and into the counter circuit (B, Z, d, β, f, R, earth,) turns on. · 1 sheet of drawings.