DE1114852B - Circuit arrangement for the detection or display of telephone charges - Google Patents

Description

In telephony systems, it is used to generate charge pulses for actuating the subscriber charge indicator and its counter in the control center known from a zoning device (tariff device) the number of impulses to be transmitted as a function of the duration and distance of the speech connection to be sent (time pulse counting).

The tax pulses intended for the subscriber charge indicator are fed into the subscriber lines in the known circuits from a common power source via contacts of a counting relay or a meter. Either the AC network (50 Hz) or a higher frequency generator via a busbar system is used as the common power source. In the latter case, the generator output depends on the network planning and on the traffic density, ie on the highest possible number of charge indicators fed simultaneously or on the number of subscriber lines connected to the generator. In all cases, measures such. B. blocking filter, provided to prevent the energy of the meter pulses not flowing in the direction of the called party. If the pulse transmission symmetrically via the speech wires on how it is carried out today using a temperature above the limit of hearing Taxfrequenz partly so is to ensure that the non-transmitted through the incision of the sine curves of the Taxfrequenz in the pulsing clicking noises produced on the subscriber line , but should be filtered out at the feed-in. These feed filters are combined in a known design with the line blocking filter as an official switch in a special device.

The disadvantage of these known arrangements is that due to the relatively strong power source for larger ones Networks due to the relatively high pulse strength of the charge pulses given on the lines Malfunctions and even damage in the subscriber lines occur in the vicinity of the control center. the Charge impulses must always be given to all subscriber lines, without subscribers to distinguish with and without its own fee indicator. The contacts of the alternator are worn out very quickly, so that these are often a source of interference and are repeatedly checked Need to become.

The invention is based on a circuit arrangement for recording or displaying telephone charges from which charge pulses for simultaneous actuation of the subscriber charge counter and the the participant in the control center associated counter circuit arrangement

for acquisition or display

of telephone charges

Applicant:

Sodeco Societe des Compteurs de Geneve, Geneva (Switzerland)

Representative: Dipl.-Ing. R. Müller-Börner,

Berlin-Dahlem, Podbielskiallee 68,

and Dipl.-Ing. H.-H. Wey, Munich 22,

Patent attorneys

Claimed priority:
Switzerland of January 9, 1959 (No. 68 198)

Paul Luscher, Geneva (Switzerland),
has been named as the inventor

are generated, and is characterized to avoid the disadvantages mentioned in that a from Tariff device-dependent switch in a DC circuit for simultaneous control of the subscriber counter is provided in the center and an oscillator and that the oscillator output from one blocking filter located in front of the central circuit without the interposition of contacts to the subscriber line is directly connected. This ensures that the oscillator at the beginning of each pulse starts to oscillate again, so that a soft start of the alternating current pulse is achieved. The transfer the interference spectrum generated by the rectangular shape of the direct current pulses controlled by the tariff device becomes a participant by transforming the square-wave impulses into approximated trapezoidal impulses the feed section of the oscillator as well as through the filter effect of the oscillator itself as a result of the selective Feeding of the tax frequency into the line prevented. A major advantage is that the The cracking noises are filtered using switch means that simultaneously control parts of the Oscillators are. It is also provided to combine the oscillator and notch filter in the same device, namely as a generator and switch at the same time, which makes a separate switch unnecessary. As a means of Blocking the taxi impulses is expedient

109 708/71

The bandstop adjusted to the tax frequency is built into the connection.

The invention is illustrated schematically in the drawing. It shows

Fig. 1 is a general circuit diagram of the invention Switching arrangement,

FIG. 2 shows a variant of the circuit of FIG. 1,

3 shows the circuit associated with the diagrams according to FIGS. 1 and 2 in detail,

Fig. 4 shows a variant of the block filter of the circuit of FIG. 3 for the case that the circuit for the Charge pulses is a phantom circle,

FIGS. 5 and 6 show a different type and division of the winding η 3 than that shown in FIGS. 3 and 4 Cases.

In Figs. 1 and 2, α and b denote the lines of a calling party. The lines end, seen in the direction of the control center, at the selector S and in the direction of the subscriber on the telephone set and the charge display. The last two devices are not shown. Z denotes the subscriber counter in the control center. The charge pulses intended to control the subscriber's charge display are generated in an oscillator O which is connected to a circuit which also contains the subscriber counter Z, a contact / and a direct current source. In the circuit according to FIG. 1, the oscillator O is in series with the subscriber counter Z and has the same current flowing through it; according to FIG. 2, O and Z are connected in parallel and have the same voltage.

The contact /, which controls the switch-on circuit of the oscillator O , is dependent on the control of the relay coil / a tariff device, which determines the setting of the charge pulse trains as a function of the zone. The contact / opens and closes with each charge pulse. The oscillator O, which generates the tax alternating current, is only excited when the contact / is closed.

The unit labeled A serves on the one hand to feed the charge pulses originating from the oscillator into the line «, b; on the other hand, it contains the lock that keeps the pulses away from the control center.

Claims (8)

PATENT CLAIMS: 1. Circuit arrangement for recording or displaying telephone charges, in which 45 charge pulses are generated for simultaneous actuation of the subscriber charge counter and the counter assigned to the subscriber in the control center, characterized in that the subscriber counter (Z) in the control center and the oscillator (O) for generating the alternating current pulses for the subscriber charge counter in one Direct current circuit, which is controlled by a switch (/) of the zoning device, and that the oscillator output is directly connected to the subscriber line (a, b) via a blocking filter (A) located in the subscriber connection line without the interposition of contacts. 2. Circuit arrangement according to claim 1, characterized in that the feed of the Oscillator is provided directly from a partial winding (ral in Fig. 3) of the oscillator coil. 3. Circuit arrangement according to claim 1 and 2, characterized in that as a means for blocking of the tax impulse a bandstop that is matched to the tax frequency is switched on in the connection is. 4. Circuit arrangement according to claim 2, characterized characterized in that the oscillator and the counter are in parallel. 5. Circuit arrangement according to claim 2, characterized in that the oscillator is a Transistor oscillator is. 6. Circuit arrangement according to claim 2, characterized in that the into the subscriber lines fed in alternating current pulses via a forming part of the filter barrier Winding (rc 3 in Fig. 3). 7. Circuit arrangement according to claim 2, characterized in that the alternating current charge pulses fed into a phantom circuit. 8. A method for implementing the circuit arrangement according to claim 2, characterized in that the pulse generator (O) and the filter (A) are arranged in a container with sticks. Considered publications:
German Patent No. 826 167;
Introduction to telephone technology by Richard Krause, Part I, III. Edition, p. 167. 1 sheet of drawings © 109 708/71 10.61