RU2019058C1 - Interlock for telephone sets placed into subscriber's line of collective use - Google Patents

Abstract

FIELD: electric communication. SUBSTANCE: interlock includes two single-threshold electronic keys 1, 2, interlocked telephone set 3, subscriber's line 4 of collective use. Interlock is intended for connection on only one subscriber and interlocking of connection of all other subscribers at moment of conversation. EFFECT: simplified design, improved reliability. 1 dwg

Description

 The invention relates to telecommunications and can be used in telephone systems with collective subscriber lines.

 A device for blocking telephone sets included in a collective subscriber line is known, comprising a zener diode, an anode of which is connected to a subscriber line wire, a thyristor optocoupler, anode and photo-thyristor anodes of which are combined and connected to an open contact of a telephone switch, while a thyristor optocoupler photothyristor is connected to the input of the telephone, and the cathode of the thyristor optocoupler emitter is connected to the zener diode cathode.

 The disadvantage of this device is that it requires a change in the conversational scheme of the telephone when connecting it to the lever switch, which limits the capabilities of the device, especially when implemented in small-sized designs of telephone sets.

 The purpose of the invention is the expansion of the capabilities of the device and its simplification.

 This is achieved by the fact that a second unipolar threshold voltage threshold electronic beam connected in parallel but opposite in polarity to the first one, which is connected in the context of one, is introduced into the blocking device for telephone sets included in a collective subscriber line containing an unipolar threshold voltage threshold electronic key from wires connecting a locked telephone to a collective subscriber line.

 The drawing shows a structural electrical diagram of a blocking device for telephones included in the subscriber line for collective use.

 The locking device for telephones included in a collective subscriber line contains a unipolar first and second threshold voltage threshold electronic keys 1 and 2, lockable telephones 3 and a collective subscriber line 4.

 A parallel connection of the first and second unipolar voltage threshold electronic keys 1 and 2 is connected in the context of one of the wires connecting the lockable telephone 3 to the collective line 4.

 As unipolar threshold voltage thresholds of electronic keys, for example, uncontrolled thyristors (dinistor) can be used.

 The device operates as follows.

 Outgoing mode.

 When you pick up the handset of any of several lockable telephones 3, the DC voltage of the central station 60V (45V) is supplied through the wires of the subscriber line 4 through the contact of the lever switch, the conversational circuit of the telephone 3 to one of the threshold electronic keys 1 or 2 in accordance with the polarity input voltage. The breakdown voltage of the electronic keys 1 and 2 is equal to half the voltage of the power supply of the central station, so the electronic key 1 or 2 breaks through and connects the telephone 3 to the collective line 4. Other telephones 3 are blocked at the same time, since the voltage in the subscriber line 4 is not enough for the breakdown of the threshold voltage thresholds of electronic keys 1.2 due to a significant voltage drop on the internal resistance of the telephone exchange power supply. The voltage drop on an open dinistor 1 or 2 is a fraction of a volt, which practically does not affect the quality of the connected telephone 3 with the handset raised.

 Incoming mode.

 A ringing alternating current voltage of 80 V passes through all voltage threshold electronic keys 1 and 2 to the ring circuits of each telephone set 3. However, in order to reduce the load on the ring generator of the central telephone exchange, it is advisable to use telephone sets with low-current ring circuits.

 Priority Subscriber Mode.

 A non-blocking telephone set, connected without a blocking device to the collective line 4, can perform a priority function for the case of an urgent intervention in a conversation by a connected subscriber of a locked telephone set 3.

 Thus, the ease of implementation, high reliability and low cost of the blocking device for telephone sets included in the subscriber line of collective use, expands the possibilities of its use, including on the principle of "director-secretary". In addition, the elimination of accidental congestion of the line of collective use by parallel subscribers provides the necessary quality of communication.

Claims (1)

 LOCKING DEVICE FOR TELEPHONE APPLIANCES INCLUDED IN A SUBSCRIBER COLLECTIVE USE LINE, containing a threshold voltage key electronic key, the first output of which is connected to the first wire of the subscriber line for collective use, and the second output is connected to the first input of the blocking telephone field, the input being different, which voltage threshold electronic key connected in parallel but opposite in polarity to the first, while the second input of the locked telephone The unit is connected to the second wire of the collective subscriber line.