JPH11146432A - Pbx and its terminal connection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple, small-sized and inexpensive PBX and a terminal connection method. SOLUTION: This PBX is provided with one interface circuit 21 connected through a codec 1 to a communication channel, a channel switching part 20 for switching and connecting the interface circuit 21 to respective terminal equipments 3a-3n and a means for connecting a tone generation circuit 22 and a power feeding circuit 23 for supplying terminal equipment operation power through the channel switching part 20 to the other terminal equipments not connected to the communication channel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a PBX (private b
ranch exchange) and its terminal connection method.

[0002]

2. Description of the Related Art FIG. 2 is a functional block diagram showing a schematic configuration of a PBX in which a plurality of communication terminals (for example, analog telephones) having more than the number of lines are connected to a digital communication line. In the figure, 1 is a codec, 2a is a PBX, 3
a to 3n indicate communication terminals, respectively. In the PBX 2a, reference numeral 20 denotes a line switching unit, reference numerals 21a to 21n denote subscriber line interface circuits, and reference numeral 22 denotes a tone generation circuit. As is well known, a telephone is configured to operate with standard power supplied from a telephone line. However, when a telephone having more than the number of lines is connected to the telephone line via a PBX, one telephone is connected. Since the standard power can be supplied to only one telephone from the telephone line, the standard power is supplied from the PBX subscriber line interface circuit to each telephone.

Next, the operation of the conventional PBX shown in FIG. 2 will be described. During communication standby, as shown in FIG. 2, all the subscriber line interface circuits 21a to 21n connected to the terminal devices 3a to 3n are switched by the line switching unit 20.
Are connected to the codec 1. That is, all of the terminal devices 3a to 3n are in a state where calling / calling is possible. Here, if there is an outgoing call or an incoming call to any of the terminal devices (for example, the terminal device 3a), the other terminal devices 3b to 3n cannot perform outgoing / incoming calls. The subscriber line interface circuits 21b to 21n connected to the terminal devices 3b to 3n are all connected to the tone generation circuit 22, and a tone indicating that communication is disabled is sent to these terminal devices 3b to 3n.

[0004]

The conventional P as described above
The BX has subscriber line interface circuits as many as the number of terminal devices to be connected, and thus has a problem that the circuit scale is increased and the cost is increased. The PBX subscriber line interface circuit not only supplies standard power to each connected terminal device, but also has various functions because it is necessary to control the interface with various connected terminal devices. Is a complex circuit that has been
This is because X has as many subscriber line interface circuits as the number of connected terminal devices. However, the connection of the communication line to any one of the terminal devices can be performed by one subscriber line interface circuit, and at the time of communication in which the communication line is connected to any one of the terminal devices, the other terminal device is connected. , A standardized tone indicating that communication is disabled is transmitted, and it is sufficient that these other terminal devices can receive this tone.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a simple, small, and inexpensive PBX and a terminal connection method thereof.

[0006]

A PBX terminal connection method according to the present invention is a PBX for switching and using a terminal device having more than the number of communication lines for a communication line, wherein the terminal is connected to the communication line. In a PBX terminal connection method for connecting a tone generation circuit to another terminal device other than the device and receiving a tone indicating that communication is impossible, the number of interface circuits is one, and the other terminal device not connected to the communication line Is connected to a power supply circuit to supply operating power so that a tone indicating that communication is disabled from the tone generation circuit can be received.

Further, the PBX of the present invention provides a PBX that switches and uses a terminal device having more than the number of communication lines for a communication line.
One interface connected to the communication line in a PBX for connecting a tone generation circuit to a terminal device other than the terminal device connected to the communication line and receiving a tone indicating that communication is disabled. Circuit, a line switching unit for switching and connecting this interface circuit to each terminal device, and power supply for supplying terminal device operating power to the other terminal devices not connected to the communication line via the line switching unit. Means for connecting circuits.

The PBX of the present invention and the terminal connection method thereof are configured as described above, so that the same operation as the conventional PBX can be performed with the interface circuits as many as the number of communication lines.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a PBX (private
FIG. 2 is a functional block diagram illustrating an embodiment of a configuration of a branch exchange. In FIG. 1, 1 is a codec.
In the PCM (pulse code modulation) communication system, this is a circuit that converts between analog signals and digital signals. A coder that converts analog original voice and image signals into PCM signals and a circuit that performs the reverse conversion. No. (dec
oder). 2 is a PB for switching and using a terminal device that is larger than the number of available communication lines.
X, 3a to 3n are terminal devices, for example, analog or digital telephones, facsimile machines, personal computers, and the like.

In the PBX 2, reference numeral 20 denotes a line switching unit, 21 denotes a subscriber line interface circuit, 22 denotes a tone generation circuit, and 23 denotes a power supply circuit. The subscriber line interface circuit 21 is connected to various terminal devices 3a to 3n.
For example, when an analog telephone or a facsimile whose voice and image are analog is connected, a PCM standardized by the codec 1 is used.
If a digital signal terminal such as a personal computer is connected, an interface for transmitting and receiving the digital signal with a standardized PCM signal is provided, and an incoming signal from a communication line is transmitted. Is configured with a circuit having a function of detecting which of the terminal devices 3a to 3n the terminal device 3a corresponds to. Reference numeral 22 denotes a tone generation circuit, which outputs a standardized tone indicating that connection is impossible to the remaining communication terminals when any terminal device is connected to the communication line. A power supply circuit 23 supplies standardized power for operating a communication terminal that is not connected to the subscriber line interface circuit 21.

Next, the operation of the PBX shown in FIG. 1 will be described. During communication standby, as shown in FIG. 1, the line connection circuit 20 connects the subscriber line interface circuit 21 to all the terminal devices. That is, all of the terminal devices 3a to 3n are in a state where calling / calling is possible. Here, if there is an outgoing call or an incoming call to any of the terminal devices (for example, the terminal device 3a), the other terminal devices 3b to 3n cannot perform outgoing / incoming calls. All of the remaining terminal devices 3b to 3n that have become disabled are connected to a circuit to which the tone generation circuit 22 and the power supply circuit 23 are connected.

In other words, the terminal devices 3b through 3
3n, a standardized tone indicating that communication is disabled is transmitted, and it is sufficient if operating power can be supplied to the terminal device so that these terminal devices can receive this tone. Without connecting the subscriber line interface circuit to each terminal device like the PBX of
The configuration is such that the tone generation circuit 22 and the power supply circuit 23 are connected. As a result, the subscriber line interface circuits need only be provided by the number of available communication lines, and the power supply circuit 23 can be a simple circuit that only supplies standardized power for operating the terminal device. In addition, the circuit size of the PBX can be reduced in size and cost as compared with the conventional PBX which requires the subscriber line interface circuits by the number of terminal devices.

In the above-described embodiment, an example in which various terminal devices are connected to the PCM line has been described. However, a case where a plurality of telephones are connected to the analog telephone line via the PBX can be similarly implemented. It is needless to say that any number of communication lines may be provided as long as the subscriber line interface circuits are provided by the number of available communication lines.

[0014]

As described above, the PBX and the terminal connection method of the present invention do not need to have complicated subscriber line interface circuits as many as the number of terminal devices, and can provide a simple, small, and inexpensive PBX. This has the effect.

[Brief description of the drawings]

FIG. 1 is a functional block diagram for explaining an embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating an example of a conventional PBX.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Codec 2 PBX 3a-3n Terminal device 20 Line switch part 21 Subscriber line interface circuit 22 Tone generation circuit 23 Power supply circuit

Claims (2)

[Claims] 1. A PBX (private branch) for switching and using a terminal device having more than the number of communication lines as a communication line.
exchange), wherein a tone generation circuit is connected to another terminal device other than the terminal device connected to the communication line, and the terminal connection method of the PBX for receiving a tone indicating that communication is disabled, the number of interface circuits is one. A power supply circuit connected to another terminal device that is not connected to a communication line to supply operating power so that a tone indicating that communication is not possible can be received from the tone generation circuit. Terminal connection method. 2. A PBX for switching and using a terminal device having more than the number of communication lines for a communication line, wherein a tone generating circuit is connected to another terminal device other than the terminal device connected to the communication line. A PBX for receiving a tone indicating that communication is disabled, one interface circuit connected to the communication line, a line switching unit for switching and connecting the interface circuit to each terminal device, and a communication line connected to the communication line. Means for connecting a power supply circuit for supplying terminal device operation power to the other terminal device via the line switching unit.