RU2812338C1 - Phone unit of pbx system with protection against parallel connection - Google Patents

Abstract

FIELD: telephone communication.

SUBSTANCE: invention relates to protecting a telephone communication channel from parallel connection of an additional telephone set. To do this, a telephone set of the PBX system with protection against parallel connection, comprising a PBX subscriber line, a ringing device, a power bridge, a lever switch, an electronic bell, a loudspeaker, a counter-circuit, a microphone amplifier, a reception amplifier, a handset consisting of a microphone and a telephone, a switch type of dialling, a keyboard, a controller, a common bus, a tone dialling unit, a liquid crystal indicator, a memory unit and a clock and calendar unit, additionally includes a protection unit included in the break of the subscriber line of the automatic telephone exchange and consisting of a voltage sensor, a processing unit, a current sensor, a switch and an RC circuit.

EFFECT: implementation of the purpose of the claimed solution.

1 cl, 1 dwg

Description

The invention relates to terminal subscriber telephone devices and can be used as a telephone device in a PBX system on general purpose telephone networks.

It is known that a telephone set is a terminal subscriber device that transmits and receives calling, address and voice signals. In this case, the telephone apparatus includes ringing devices, conversational devices, matching and switching devices [1, 2].

The closest in technical essence to the proposed invention is the multifunctional telephone set of the PBX system chosen as a prototype, the structural diagram and technical capabilities of which are described in a well-known source (Fig. 2.3, p. 18) [2]. This device contains a PBX subscriber line, a calling device, a power bridge, a lever switch (RP), an electronic bell, a loudspeaker, a counter circuit, a microphone amplifier, a reception amplifier, a handset consisting of a microphone and a telephone, a dial switch, a keyboard, a control controller, a common bus, a tone dialing unit, a liquid crystal display, a memory unit and a clock and calendar unit. This device provides expanded functionality of the conversation path and the dial path, sending a call by pulse and tone dialing, receiving a call via an electronic bell and loudspeaker, conducting telephone communication and hanging up at the end of conversations using a lever switch when the handset is placed on the device.

The disadvantage of the known telephone set is the lack of protection against parallel connection of a “pirate device” to the PBX subscriber line, which leads to a deterioration in the quality of communication and unacceptable use of the tariff resource of the main PBX subscriber.

The purpose of the invention is to expand the functionality of the device and provide protection against parallel connection of an additional telephone device to the subscriber line.

This goal is achieved by the fact that the telephone apparatus of the PBX system is protected from parallel connection, containing a PBX subscriber line, a ringing device, a power bridge, a lever switch, an electronic bell, a loudspeaker, a counter-circuit, a microphone amplifier, a reception amplifier, a handset as part of a microphone and telephone, a dialing type switch, a keyboard, a control controller, a common bus, a tone dialing unit, a liquid crystal indicator, a memory unit and a clock and calendar unit, it additionally includes a protection unit included in the PBX subscriber line break and consisting of a voltage sensor , a processing unit, a current sensor, a key and a resistive-capacitive circuit, with the first input-output of the ATS subscriber line connected in parallel to the first input-output of the current sensor and to the first input-output of the voltage sensor, the second input-output of which is connected in parallel to the second input-output of the subscriber line of the automatic telephone exchange and to the first input-output of the resistive-capacitive circuit, the third input-output of the voltage sensor is connected to the first input-output of the processing unit, the second and third input-outputs of which are connected, respectively, to the second input-output of the current sensor and to the first input-output of the switch, the second input-output of which is connected to the second input-output of the resistive-capacitive circuit, the third input-output of the current sensor is connected to the first input-output of the supply bridge, the second, third and fourth input-outputs of which are connected to the first inputs - the outputs, respectively, of the ringing device, the lever switch and the electronic bell, the second input-output of which is connected to the input-output of the loudspeaker, the second and third input-output of the lever switch are connected, respectively, to the third input-output of the resistive-capacitive circuit and to the first input-output of the anti-local circuit, the second input-output of which is connected to the fifth input-output of the power bridge, the sixth input-output of which is connected to the first input-output of the dialing type switch, the second input-output of which is connected to the second input-output of the calling device, the third, the fourth, the fifth, sixth, seventh and eighth inputs-outputs of the anti-local circuit are connected, respectively, to the input-output of the microphone amplifier, the receiving amplifier, to the third input-output of the dial type switch, to the first input-output of the keyboard, to the first input-output of the control controller and to input-output of the tone dialing unit, the input-output of the microphone amplifier is connected to the microphone output of the handset, and the output of the receiving amplifier is connected to the telephone input of the handset, the second input-output of the keyboard is connected to the second input-output of the control controller, to the third input-output of which it is connected the first input-output of a common bus, the second, third, fourth and fifth input-outputs of which are connected, respectively, to the second input-output of the tone dialing unit, to the inputs and outputs of the liquid crystal indicator, the memory unit and the clock and calendar unit.

A comparable analysis with the prototype shows that the proposed telephone set of the PBX system with protection against parallel connection is distinguished by the presence of new blocks: a protection block consisting of a voltage sensor, a processing unit, a current sensor, a key and a resistive-capacitive circuit, as well as a change in connections between known blocks telephone set.

When introducing new blocks in the specified connection with the remaining elements of the circuit into the inventive telephone set of a PBX system with protection against parallel connection, the above blocks exhibit new properties, which makes it possible to achieve the goal.

Thus, the claimed telephone set of the PBX system with protection against parallel connection meets the invention criterion of “novelty”. A comparison of the proposed solution with other technical solutions shows that the newly introduced blocks are feasible, well known to specialists in the field of technology and additional creativity, taking into account the explanations given below, is not required to reproduce them.

The proposed solution differs significantly from currently known solutions. This allows us to conclude that the proposed telephone set of the PBX system with protection against parallel connection meets the invention criterion of “significant differences”.

The claimed solution does not clearly follow from the prior art and has an inventive step.

The inventive telephone system of a PBX system with protection against parallel connection can be implemented using existing equipment, electrical and communications equipment, switching devices and is industrially applicable.

The drawing shows a structural electrical diagram of a telephone set of a PBX system with protection against parallel connection.

A telephone set of the PBX system with protection against parallel connection contains a subscriber line PBX 1, a protection unit 2, included in the break of the PBX line 1 and consisting of a voltage sensor 3, a processing unit 4, a current sensor 5, a key 6 and a resistive-capacitive circuit 7, a ringing device 8, power bridge 9, lever switch (RP) 10, electronic bell 11, loudspeaker 12, anti-local circuit 13, microphone amplifier 14, reception amplifier 15, handset 16 consisting of microphone 17 and telephone 18, dialing type switch 19, keyboard 20, control controller 21, common bus 22, tone dialing unit 23, liquid crystal indicator 24, memory unit 25 and clock and calendar unit 26.

The first input-output of the subscriber line of ATS 1 is connected in parallel to the first input-output of the current sensor 5 of the protection unit 2 and to the first input-output of the voltage sensor 3, the second input-output of which is connected in parallel to the second input-output of the subscriber line of ATS 1 and to the first input-output of the resistive-capacitive circuit 7, the third input-output of the voltage sensor 3 is connected to the first input-output of the processing unit 4, the second and third input-outputs of which are connected, respectively, to the second input-output of the current sensor 5 and to the first input-output of the key 6, the second input-output of which is connected to the second input-output of the resistive-capacitive circuit 7, the third input-output of the current sensor 5 is connected to the first input-output of the supply bridge 9, the second, third and fourth inputs-outputs of which are connected to the first inputs- the outputs, respectively, of the ringing device 8, the lever switch 10 and the electronic bell 11, the second input-output of which is connected to the input-output of the loudspeaker 12. The second and third inputs-outputs of the lever switch 10 are connected, respectively, to the third input-output of the resistive-capacitive circuit 7 and to the first input-output of the anti-local circuit 13, the second input-output of which is connected to the fifth input-output of the supply bridge 9, the sixth input-output of which is connected to the first input-output of the dial type switch 19, the second input-output of which is connected to the second input- output of the ringing device 8. The third, fourth, fifth, sixth, seventh and eighth inputs-outputs of the anti-local circuit 13 are connected, respectively, to the input-output of the microphone amplifier 14, the receiving amplifier 15, to the third input-output of the dialing type switch 19, to the first input - the output of the keyboard 20, to the first input-output of the control controller 21 and to the input-output of the tone dialing unit 23. The input of the microphone amplifier 14 is connected to the output of the microphone 17 of the handset, and the output of the receiving amplifier 15 is connected to the input of the telephone 18 of the handset 16, the second input-output of the keyboard 20 is connected to the second input-output of the control controller 21, to the third input-output of which the first is connected input-output of the common bus 22, the second, third, fourth and fifth inputs-outputs of which are connected, respectively, to the second input-output of the tone dialing unit 23, to the inputs-outputs of the liquid crystal indicator 24, memory unit 25 and clock and calendar unit 26.

Subscriber line 1 of the automatic telephone exchange is intended for access to an automatic telephone exchange. This can be done using a telephone distribution cable.

Protection block 2, included in the break of the subscriber line of ATS 1 and consisting of a voltage sensor 3 connected in parallel to the wires of the subscriber line of ATS 1, processing node 4, current sensor 5 connected to one of the wires of line 1, for example, wire 6, key 6 and resistive-capacitive circuit 7, is designed to protect against “pirate” connections from the installation location of the unit (usually in an apartment in front of the telephone) right up to the output terminals of the telephone exchange in case of illegal connections without breaking the loop.

The operating principle of protection block 2 is as follows. Protection block 2 constantly analyzes the state of the subscriber line of the PBX 1 and when the voltage drops in line 1 below the set limit due to the removal of the handset and an attempt to dial a number from an illegal telephone, block 2 loads line 1 with a specially designed resistive-capacitive circuit 7, thus prohibiting further dialing. When the handset 16 is picked up on the main (protected) telephone set in the protection block 2, the current sensor 5 is triggered, turning off the protection and connecting the subscriber line 1 to the inputs and outputs of the nodes (blocks) of the telephone set.

Resistive-capacitive circuit 7 consists of active resistance R and capacitance C connected in parallel. In this case, the first input-output of the resistive circuit 7 is connected to one of the wires (wire a) of line 1, and the second input-output of the resistive circuit is connected to the input-output of the key 6. Two wires of the protection block 2 from the second input-output of the block are connected to the wires at the input of the protected telephone, and the wires from the first input-output of the block 2 are connected to the wires of the subscriber line 1 going to the telephone exchange.

The principle of operation of such a system is as follows: protection unit 2 constantly analyzes the state of the subscriber line of PBX 1 and if the voltage in the line drops below the set limit at the moment of picking up the handset and attempting to dial a number from an illegal device, it loads the line with a specially designed resistive-capacitive circuit 7, prohibiting such further dialing. When the handset on the main (protected) telephone is lifted, current sensor 5 in protection unit 2 is triggered, turning off the protection.

The calling device 8 includes an integrated circuit (IC) dialer (DN), pulse (IR) and conversational (RC) keys. The integrated circuit of the dialer is powered from subscriber line 1 of the telephone exchange and ensures the operation of the integrated circuit when dialing a number, as well as in conversational mode. In the “End Light” mode, when the handset 16 is placed on the lever, the power is removed from it.

The supply bridge 9 is designed to generate the power supply voltage for calling devices (integrated circuit dialer, electronic ringer ringing device 8) and conversational devices (microphone amplifier 14 and reception amplifier 15, microphone 17 and telephone 18, handset 16).

The lever switch 10 provides the initial connection of calling devices, and after removing the handset 16 from the telephone, it ensures the connection of voice devices and a dialer and disconnects the calling devices.

The electronic bell 11 is designed to receive call signals coming from the subscriber line of the automatic telephone exchange 1, convert the ringing electrical signals into acoustic signals and then issue them to the loudspeaker 12, which ensures playback of the received call signals in accordance with the melody used in the telephone set.

A piezoelectric transducer, which is a piezoelectric crystal, can be used as a loudspeaker 12. When an alternating voltage is applied to it from the output of the electronic bell 11, mechanical vibrations arise in it, generating a strong sound.

The anti-local circuit 13 is designed to separate the reception and transmission circuits of the telephone set. It is built on a differential transformer. In this case, the transmitting part is separated from the receiving part by a differential system (DS), the balancing of which is provided by a balanced circuit (BC).

The microphone amplifier 14 is designed to amplify the electrical signals generated by the microphone 17 to the level necessary for transmitting signals over the subscriber line of the automatic telephone exchange 1 of various lengths. It can be made in one, two or three stages.

The reception amplifier 15 is designed to amplify the speech signal received from the subscriber line 1 to the level necessary for normal operation of the telephone 18. It can be made in one, two or three stages. In this case, a volume control is provided in one of the amplifier stages.

The handset 16, consisting of a microphone 17 and a telephone 18, is intended for conducting conversations with subscribers via subscriber line 1 of the automatic telephone exchange.

The microphone 17 of the handset 16 is designed to convert the speech signals of the speaking subscriber into electrical signals and then transmit them to the input of the microphone amplifier 14. An electrodynamic microphone of the DEMK-1A type can be used as microphone 17. In this case, at the input of the microphone amplifier 14, a cascade of pre-amplification of the signals of the microphone 17 and resistance matching is turned on.

Telephone 18 is designed to convert electrical signals coming from the output of the reception amplifier 15 into speech signals.

The dialing type switch 19 is designed to select the call mode, pulse or tone, depending on whether the called subscriber has a telephone with pulse or tone dialing.

The keyboard 20 is a board on which there are buttons for dialing numbers from 0 to 9 and buttons that are rigidly assigned to the functions performed by the telephone and expanding its functionality, including, such as putting a call on hold, call forwarding, volume control handsets, one-touch dial buttons, ring indicator, last number redial button and a number of other functions.

The control controller 21 is a microprocessor that is designed to control the communication between the switching system and the subscriber interface, as well as control the execution of all functions of the telephone set. In this case, the control controller 21 determines the state of the handset (determining the moment of its removal), function buttons and programming buttons of the keyboard 20, transmits information to the subscriber set of the telephone exchange about the subscriber picking up the handset or pressing a button.

When sending a text, acoustic or optical message from the station to the subscriber, the controller 21 controls the operation of the electronic bell 11, the loudspeaker 12, the liquid crystal indicator 24 and the LEDs of the keyboard buttons 20.

The PC bus of the local area network is used as the common bus 22.

Tone dialing unit 23 is designed to provide calls to subscribers included in the communication channel.

Currently, telephone networks in accordance with the international standard DTMF (Dual-Tone Multiple Frequency) use a dual-frequency tone dialing system. Tone dialing uses two frequencies. In this case, each dialed digit is represented by a combination of two non-harmonic tones. To implement this dialing method, a DTMF dialer integrated circuit is used in the calling device.

The liquid crystal indicator 24 is a mini display and is designed to display messages to the subscriber (for example, the called subscriber is busy, a non-existent number has been dialed, etc.), as well as signals transmitted and received from the subscriber line of the PBX 1.

The memory unit 25 includes a random access memory (RAM) and a read-only memory (ROM), which stores programming data for certain functions of the PBX station software.

The 26 clock and calendar block is designed to generate uniform time signals, including date - year, month, day and day of the week, current time indicators - hours and minutes. Block 26 is made using a commercially available large scale integrated circuit (LSI).

A telephone set of a PBX system with parallel connection protection provides the following modes and types of connections:

a) sending call signals via the PBX subscriber line with pulse or tone dialing of the called subscriber;

b) receiving call signals on a loudspeaker and displaying them on a liquid crystal display;

c) expanded capabilities of the dialing path:

redialing a number with one keystroke (when the called party does not pick up the phone or is temporarily busy),

automatic search for a subscriber using numbers pre-programmed in the telephone memory;

possibility of receiving an optical or acoustic signal,

using a loudspeaker to receive acoustic signals,

automatic call redial if the called party does not answer,

automatic dialing of programmable numbers,

dialing a number without picking up the handset,

combined dialing (using pulse and tone dialing),

holding an external connection when making inquiries, light signaling about waiting external calls, the ability to use a pulse or frequency (DTMF) method of dialing a subscriber number;

d) conducting negotiations with the called subscriber using a handset;

e) hang up at the end of the conversation with the subscriber;

e) expanded capabilities of the conversation path: volume control in the handset, “hands-free” when talking, that is, full loudspeaker mode;

ensuring the transmission and reception of information in both analogue and digital form;

g) display of telephone operation signals on the liquid crystal display (subscriber answer, busy, hang up, as well as date signals, current time, etc.);

i) emergency operation in the event of a power failure in the external network.

The principle of operation of a telephone set of a PBX system with parallel connection protection is as follows. Making a call.

When picking up the handset 16, the lever switch 10 connects the telephone set (TA) to the subscriber line 1, connecting it to the PBX. As a result, the dialer integrated circuit (IC) is initially set to dialing readiness mode.

In the ready-to-dial mode, the integrated circuit of the dialer generates a control signal for the pulse key (IK) and the conversation key (PK). Having received these signals, the conversational unit, including a counter-circuit 13, a microphone amplifier 14, a telephone amplifier 15 and a handset 16 consisting of a microphone 17 and a telephone 18, is connected to the line using a conversation key (RC) and the station's response is heard in the handset 16. The pulse key (IR) is in the open (closed) state at this moment.

The subscriber starts dialing the number. When you touch the keyboard buttons, the integrated circuit of the dialer generates a sequence of pulses that control the operation of the IR and RC. The pulse switch short-circuits the line and opens it, generating direct current messages that control the operation of the telephone exchange. The conversation key disconnects the conversation unit from the common wire for the duration of the dialing messages, which eliminates the unpleasant clicks in the handset when dialing a number.

At the end of the dialing, the conversational key (RC) reconnects the conversational node and tone messages from the telephone exchange are heard in the handset, indicating that the connection has been established and the call signal has arrived on the line of the called subscriber. When the called subscriber picks up the handset, a connection is established between the two subscribers.

Call signals are received via line 1 of the telephone exchange through the current sensor 5 and the power bridge 9. In this case, call signals from the subscriber line 1 are sent to the electronic bell 11, which converts the ringing electrical signals into acoustic ones and transmits them to the input of the loudspeaker 12. The loudspeaker 12 reproduces the received ringing signals in accordance with the melody used in the telephone.

Conversation transfer.

The conversational part of the telephone circuit for transmission includes a microphone 17 of the handset 16 and a microphone amplifier 14. In this case, the acoustic signals of the speaking subscriber are converted by the microphone 17 into electrical signals, amplified by the microphone amplifier 14 to the required level and through the counter-circuit 13 and the lever switch 10 spoken signals are transmitted via line 1 to the called subscriber.

Reception of conversation.

The conversational part of the telephone circuit for reception includes a counter-circuit 13, a reception amplifier 15 and a telephone 18 of a microtelephone handset 16. In this case, conversational signals from the subscriber line of the telephone exchange 1 through a current sensor 5, a resistive-capacitive circuit 7, a power bridge 9, a lever switch 10 and the anti-local circuit 13 are supplied to the reception amplifier 15, which amplifies them to the required level and transmits them to the input of the telephone 18 of the microtelephone handset 16. The telephone 18 converts the incoming electrical signals into speech signals for perception by the speaking subscriber.

At the end of the conversation, the handset returns to the lever. The lever switch (RP) opens the circuit and the telephone circuit (TA) goes into standby mode. In standby mode, the power circuit of the microcircuit provides power to the random access memory (RAM) of the LV IS, which stores the last dialed number, the “hang up” circuit prohibits dialing from the keyboard in order to save the last dialed number, and the ringing device 8 is ready to receive PBX call signals .

When a call signal is received from the PBX, the calling device 8 produces sound signals informing about a call by another subscriber. Before picking up the handset 16, the telephone circuit is in standby mode.

When the handset is picked up, the integrated circuit is reset to its original state, with the only difference being that instead of the “Station Answer” signal (beep), the caller’s voice is heard in the handset.

When you briefly press the lever switch or touch the “End Call” button on the keyboard’s typing field using the “End Call” scheme, the telephone set is returned to its initial state.

The technical efficiency of the proposed invention lies in expanding the functionality and ensuring protection of the telephone set from the parallel connection of an additional telephone set, achieved through the introduction of a protection block in the specified composition and the implementation of known blocks with improved characteristics, which helps improve the quality of communication and eliminate unacceptable consumption of tariff resources main subscriber of the PBX.

The advantage of the proposed invention is also that the telephone takes half the time to dial a subscriber's number compared to existing telephones and reduces the likelihood of false alarms of the calling system due to random noise.

At the same time, an increase in the convenience of using the telephone is also achieved through the use of a push-button dialer with the ability to switch from one type of dialing to another, automatically repeating the call if the called subscriber does not answer, which greatly facilitates the work of the subscriber, speeds up the process of establishing connections and increases the convenience of using the telephone apparatus.

Information sources.

1. Military switching systems and telephony. B.A. Gordienko, V.N. Filippov. Ed. V.A. Gordienko - VAS, 1977.

2. T.I. Ivanova. User terminals and computer telephony. -M.: Eco-Trends, 1999 (prototype).

Claims (1)

A telephone set of a PBX system with protection against parallel connection, containing a PBX subscriber line, a ringing device, a power bridge, a lever switch, an electronic bell, a loudspeaker, a countercircuit, a microphone amplifier, a reception amplifier, a handset consisting of a microphone and a telephone, a dialing type switch , a keyboard, a control controller, a common bus, a tone dialing unit, a liquid crystal indicator, a memory unit and a clock and calendar unit, characterized in that it additionally includes a protection unit included in the break of the subscriber line of the PBX and consisting of a voltage sensor, a processing unit , a current sensor, a key and a resistive-capacitive circuit, wherein the first input-output of the PBX subscriber line is connected in parallel to the first input-output of the current sensor and to the first input-output of the voltage sensor, the second input-output of which is connected in parallel to the second input-output subscriber line of the automatic telephone exchange and to the first input-output of the resistive-capacitive circuit, the third input-output of the voltage sensor is connected to the first input-output of the processing unit, the second and third input-outputs of which are connected, respectively, to the second input-output of the current sensor and to the first input- the output of the switch, the second input-output of which is connected to the second input-output of the resistive-capacitive circuit, the third input-output of the current sensor is connected to the first input-output of the supply bridge, the second, third and fourth input-outputs of which are connected to the first input-outputs, respectively ringing device, lever switch and electronic bell, the second input-output of which is connected to the input-output of the loudspeaker, the second and third input-output of the lever switch are connected, respectively, to the third input-output of the resistive-capacitive circuit and to the first input-output of the anti-local circuit, the second the input-output of which is connected to the fifth input-output of the power bridge, the sixth input-output of which is connected to the first input-output of the dialing type switch, the second input-output of which is connected to the second input-output of the ringing device, third, fourth, fifth, sixth , the seventh and eighth input-output of the anti-local circuit are connected respectively to the input-output of the microphone amplifier, the reception amplifier, to the third input-output of the dialing type switch, to the first input-output of the keyboard, to the first input-output of the control controller and to the input-output tone dialing unit, the input of the microphone amplifier is connected to the microphone output of the handset, and the output of the reception amplifier is connected to the telephone input of the handset, the second input-output of the keyboard is connected to the second input-output of the control controller, to the third input-output of which the first input is connected. the output of a common bus, the second, third, fourth and fifth inputs and outputs of which are connected, respectively, to the second input and output of the tone dialing unit, to the inputs and outputs of the liquid crystal indicator, the memory unit and the clock and calendar unit.

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