JPS6355262B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a complex switching system capable of switching and connecting telephone premises and data terminals,
In particular, in a complex switching system that allows exchange connections between telephones to be made using alternating current signals in the same way as between data terminals, and also allows calls to be made between telephones even when the exchange becomes inoperable. Regarding telephone connection methods.

2. Description of the Related Art Conventionally, in a complex switching system that handles both telephones and data terminals, switching connections between data terminals are performed by sending and receiving control signals via alternating current lines. On the other hand, telephone exchange connections were made using direct current signals as usual.
For this reason, AC lines cannot be used when connecting telephones to exchanges, and the number and types of lines have increased, creating a major hurdle in simplifying the system configuration. In addition, in the conventional system described above, if the central control unit of the telephone goes down and exchange connection becomes impossible, not only data terminal connections but also communication by telephone cannot be made. There was a risk of major disruption to operations between branches.

The present invention has been made focusing on the above circumstances,
The purpose of this is to enable telephone connections to be made using alternating current so that alternating current circuits can be used, and also to enable telephone connections to be made and maintain telephone functionality even if the exchange is down. The purpose of this invention is to provide a telephone connection method in a complex switching system.

In the present invention, a conversion circuit is provided between each telephone and the line, which converts the activation/holding signal of the telephone from direct current to alternating current, and performs a ringing operation of the telephone by receiving this alternating current activation/holding signal, and By detecting an abnormality in the central control unit of the exchange using an abnormality detection circuit, and installing a connection circuit within the exchange that directly connects the telephone line when this is detected,
Achieve the above objectives.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the composite switching system in the same embodiment, where 1 is a composite switching system;
2 and 3 indicate data terminals, and 4 and 5 indicate telephones, respectively.

The composite exchange 1 has a switching circuit 15 to which each data terminal 2, 3 and each telephone 4, 5 are connected via lines 6, 7, 8, 9 and line circuits 11, 12, 13, 14. By switching and controlling the switching circuit 15 by the central control unit 16, switching connections are established between each telephone set 4 and 5 and between each data terminal 2 and 3. In addition, the composite switch 1 has an abnormality detection circuit 17 and lines 6, 7, 8, and 9.
It has a built-in connection circuit 18. The abnormality detection circuit 17 detects an abnormality such as runaway of the central control unit, and when this abnormality is detected, the connection circuit 18 is driven to directly connect the telephones 4 and 5.
Note that 19 is a tone receiver for transmitting a dial tone DT to the calling side telephone and receiving and detecting each frequency signal (MF signal) from the calling side telephone.

FIGS. 2 and 3 show the abnormality detection circuit 17.
and the configuration of the connection circuit 18, respectively. That is, the abnormality detection circuit 17 detects the command signal that is generated from the central control device 16 at regular intervals when it is no longer generated.
1 and outputs an abnormality detection signal, which changes the switching transistor 72 from conductive to non-conductive and deenergizes the relay (E) 73. On the other hand, the connection circuit 18 connects the normally open contacts e ₁ and e ₂ of the relay (E) 73 between the lines 8 and 9, respectively, and connects the connection ends of these normally open contacts e ₁ and e ₂ to the line circuit. Normally closed contacts e ₃ , e ₄ and e ₅ , e ₆ of relay (E) 73 are inserted between the relays 13 and 14, respectively. Therefore, in the connection circuit 18, when an abnormality occurs in the central control unit 16 and the relay (E) 73 is deenergized, the normally open contacts e ₁ and e ₂ are closed, and the normally closed contacts e ₃ , e ₄ and e ₅ and _e6 are opened, and the lines 8 and 9 of each telephone set 4 and 5 are disconnected from the line circuits 13 and 14 and directly connected.

In such a system, conversion circuits 20 and 30 are provided between the telephones 4 and 5 and the lines 8 and 9, respectively, as attached to the telephones. FIG. 4 is a block diagram showing the configuration of these conversion circuits 20 and 30. In addition, in the figure, exchange circuit 2
Only 0 is shown, and the explanation of the conversion circuit 30 is omitted.

The conversion circuit 20 inputs the voice signal or MF signal sent from the telephone 4 via the transformer 21, passes these signals through a low pass filter (LPF) 22, and amplifies them with the amplifier 23.
It is sent to line 8 via synthesis circuit 24 and hybrid transformer 25. Also, the voice signal sent from the composite exchange (FIG. 1) via the line 8 is input via the hybrid transformer 25, and this signal is passed through the synthesis circuit 26 and the low pass filter (LPF) 27 to the amplifier 28. After amplifying the signal, it is sent to the telephone 4 via a transformer 29. Here, each of the reduction pass filters (LPFs) 22 and 27 are for separating audio frequency signals such as audio signals and MF signals from control signals to be described later.

By the way, the conversion circuit 20 includes a hook operation detection circuit 31 that detects a hook operation of the telephone 4, a control signal transmission circuit 32, and a control signal reception circuit 33. The hook operation detection circuit 31 is provided in a line for guiding voice signals etc. from the telephone 4 to the transformer 21, and is composed of a power supply 34 and a relay (A) 35 for applying DC voltage to the hook switch of the telephone 4. There is. In addition, the control signal transmission circuit 32
The alternating current control signal f ₁ generated by the control signal oscillator 36 is gate-controlled by the gate circuit 37 and then output to the synthesis circuit 24. The control signal f ₁ is output to the synthesis circuit 24 and the hybrid transformer 2.
5 and then sent to line 8. Here, in the gate circuit 37, the normally closed contacts d ₁ and t ₃ of the relay (D) and relay (T), which will be described later, are closed, and the normally open contact a ₁ of the relay (A) 35 is closed. The gate is configured to open at certain times. On the other hand, the control signal receiving circuit 33 gate-controls the control signal sent via the line 8 and introduced via the hybrid transformer 25 and the synthesis circuit 26 with a gate circuit 38, and then extracts it with a band pass filter (BPE) 39. ing. The extracted control signal is then supplied to the relay (D) 42 via the amplifier 41, thereby energizing the relay (D) 42. Here, the gate circuit 38 operates when the transfer contact _a2 of the relay (A) 35 is switched to the normally closed terminal side.
Alternatively, the gate is configured to open only when the transfer contact _a2 is switched to the normally open terminal side and the normally open contact _d2 of the relay (D) 42 is in the closed state.

Further, the conversion circuit 20 includes the control signal receiving circuit 3
When a control signal is detected at 3, the telephone 4 assumes this is an incoming call, displays the call on the telephone 4, and sends a ringing tone (RBT) to the line 8. This paging circuit consists of a paging control circuit 43, a paging display circuit 44, and a ringing tone (RBT) transmitting circuit 45. The call control circuit 43 has a relay (T) 46 and a relay R47, in which the normally open contact _d3 of the relay (D) 42 is closed and the normally closed contact t of the relay (T) 46 is closed. ₂ is energized only when it is held in the closed state. Further, the relay (T) 46 is a normally open contact a ₃ of the relay (A) 35.
It is designed to be energized only when the relay (D) 42 and the normally open contacts d ₄ and t ₁ of the self 46 are both closed. on the other hand
The RBT transmitting circuit 45 is configured to gate-control the ring tone RBT generated by the RBT oscillator 48 with a gate circuit 49 and then output it to the synthesis circuit 24, and the ring tone RBT is transmitted through the synthesis circuit 24 and the hybrid transformer 25, respectively. It is sent to line 8. The call display circuit 44 is composed of a series circuit of the normally open contact r ₂ of the relay (R) 47 and the power supply 51, and when the normally open contact r ₂ is closed, the telephone 4
A buzzer (B) 52 installed at the terminal is driven to generate a ringing tone.

Next, the operation of the composite exchange system configured as above will be explained. First, if the central control device 16 of the complex exchange 1 is operating normally, the relay (E) 73 of the abnormality detection circuit 17 is in an energized state, so each line 8, 9 is connected to the line circuit 1.
3 and 14.

In this state, when the telephone 4 is turned off, this causes the hook operation detection circuit 31 of the conversion circuit 20 to
is detected, the gate circuit 37 of the control signal transmitting circuit 32 becomes open, and as a result, the control signal f ₁ is sent to the multifunction telephone 1 via the line 8. At this time, in the conversion circuit 20, the relay (A) 35 is energized as the telephone 4 is turned off, and the gate circuit 38 is closed. Therefore, even if the control signal f ₁ leaks into the control signal receiving circuit 33, the control signal receiving circuit 33 will not malfunction. In the compound exchange 1, the line circuit 13 detects the control signal _f1 , and when detected, the switching circuit 15 switches between the line circuit 13 and the tone receiver 1.
9 and sends the dial tone DT back to the telephone 4. When this dial tone DT is confirmed on the telephone 4 and the push-button dial is operated, an MF signal is generated, and this MF signal is combined with the control signal f ₁ in the conversion circuit 20 and then sent to the complex exchange 1. In the composite exchange 1, the MF signal is sent to the tone receiver 19.
The switching circuit 15 connects the line circuits 13 and 14 according to the received dial number. Therefore, the control signal f ₁ from the telephone 4 is supplied to the conversion circuit 30 . The conversion circuit 30 detects the control signal f ₁ using the control signal receiving circuit 33 . Then, relay (D)
42 energizes the relay (R) 47 of the call control circuit 43, which drives the call display circuit 44 and the RBT transmission circuit 45, respectively, and as a result, the buzzer (B) 52 of the telephone 5 rings and the call is acknowledged. This occurrence is notified and a ring tone RBT is sent to the telephone 4. In this state, when the telephone 5 is operated off-hook and answered, the conversion circuit 30 connects the relay (A) 35 and the relay (T).
46 are sequentially energized, the relay (R) 47 is restored, and as a result, the ringing by the buzzer (B) 52 and the transmission of the ring tone RBT are respectively stopped. Thus, the connection between the telephones 4 and 5 is completed, and both the telephones 4 and 5 are in a talking state.

Thereafter, when the call ends and, for example, the telephone 4 is turned off, the conversion circuit 20 stops sending out the control signal _f1 because the relay (A) 35 is restored, and returns to the initial state. On the other hand, when the conversion circuit 30 stops sending out the control signal _f1 , the relay (D) 42 of the control signal receiving circuit 33
is restored, and when the telephone 5 is turned off, the relay (A) 35 and the relay (T) 46 are restored and returned to their initial states.

By the way, if the central control unit 1 of the complex switch 1
6 goes out of control, the command signal that had previously been generated at regular intervals is no longer generated, so the relay (E) 73 of the abnormality detection circuit 17 is restored and each contact e ₁ , ~e of the connection circuit 18 ₆ is switched. As a result, the lines 8 and 9 are separated from the line circuits 13 and 14, respectively, and are directly connected to each other. Then, if you turn off either phone in this state,
A control signal f ₁ is sent from that conversion circuit to the other conversion circuit, and the conversion circuit that receives this causes the buzzer (B) of the telephone to sound to indicate a call and sends back a ring tone RBT. Then, when the called party telephone picks up and responds, both telephones become connected.

In this way, according to this embodiment, the conversion circuit 2
Since the control signal _f1 is generated by 0 and 30 to make a call, the telephones 4 and 5 can be connected even with an AC line, and as a result, the DC line can be made unnecessary. The system configuration can be simplified. In addition, in this embodiment, since the composite exchange 1 is provided with the abnormality detection circuit 17 and the connection circuit 18 operated by the abnormality detection circuit 17, even if the central control device 16 goes down, the telephone 4,
A telephone call can be made by directly connecting the terminals 5 and 5 and making a call using the functions of the conversion circuits 20 and 30. Therefore, for example, it is possible to minimize the number of communication routes between the head office and branch offices, and to reduce operational hindrances as much as possible. Also,
In the method of this embodiment, the relay of the abnormality detection circuit 17
(E) 73 is energized when the central control unit 16 is operating normally, so even when an abnormality occurs in the central control unit 16, as well as in the event of a power outage of the complex exchange 1, etc.
Lines 8 and 9 can be directly connected automatically.

Note that the present invention is not limited to the above embodiments. For example, as the configuration of the connection circuit 18, the lines 8 and 9 may be switched and connected using transfer contacts. In this way, the number of contacts used can be reduced and the configuration can be simplified. Further, in the above embodiment, a pair of telephones is directly connected, but a plurality of pairs of telephones may be directly connected. In addition, the number of connected telephones, the configuration of the conversion circuit, the configuration of the abnormality detection circuit, etc. can be modified in various ways without departing from the gist of the present invention.

As described in detail above, a switching circuit is provided between each telephone and the line, which generates an AC activation/holding signal and has a calling function, and the complex switch is equipped with an abnormality detection circuit of the central control unit and an abnormality detection circuit when an abnormality is detected. According to the present invention, which is provided with a connection circuit that directly connects each predetermined telephone set, it is possible to connect the telephone sets using alternating current, so that the alternating current line can be used, and even if the exchange is down, the telephone sets can be connected. It is possible to provide a telephone connection method in a complex switching system that can perform the following operations and maintain telephone functions.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing a composite exchange system according to an embodiment of the present invention, FIGS. 2 to 4 show main parts of the composite exchange system, and FIG. 2 is a schematic configuration of an abnormality detection circuit. 3 and 3 are schematic configuration diagrams of the connection circuit, and FIG. 4 is a schematic configuration diagram of the conversion circuit. 1...Multiple switchboard, 2, 3...Data terminal, 4, 5
...Telephone, 6,7,8,9...Line, 17...Abnormality detection circuit, 18...Connection circuit, 20,30...Conversion circuit, 31...Hook operation detection circuit, 32...Control signal transmission circuit, 33...Control signal reception circuit, 43...calling control circuit, 44...calling display circuit, 45...ringing tone (RBT) transmission circuit;

Claims (1)

[Claims] 1. In a complex switching system in which telephones and data terminals are exchanged using a complex exchange, a conversion circuit is provided between the telephone and its line, and the telephone is supplied with communication current from the conversion circuit, and on the calling side The conversion circuit detects the hook-off operation of the telephone, and sends an AC control signal from the conversion circuit as an activation hold signal to the complex exchange, and on the receiving side, when the control signal arrives via the compound exchange, the conversion circuit sends an AC control signal to the conversion circuit. The lever control signal is detected as an incoming call, and from this point until the telephone is operated off-hook and answered, connection is established between each telephone by at least displaying a call on this telephone, and the abnormal state is detected in the composite exchange. an abnormality detection circuit for detecting an abnormality, and a connection circuit for disconnecting and directly connecting predetermined telephone sets to be connected to each other when an abnormality is detected by the abnormality detection circuit from the composite exchange, and detecting the abnormality when the composite exchange operates abnormally. 1. A telephone connection method in a complex switching system, characterized in that after each conversion circuit is directly connected by a detection circuit and a connection circuit, communication between each telephone set is made possible by these conversion circuits.