JPH0342535B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a telephone communication device that selects one of a plurality of telephone slave units and activates a telephone line between the telephone slave unit and the telephone master unit.

Japanese Patent Publication No. 52-2564 discloses an intercom device in which a large number of slave units are connected in parallel to a common voice line and a control line, and the communication circuit of the slave unit selected as the master unit is connected to the voice line. is disclosed.

However, although the intercom device reduces the number of cables between the parent device and the slave devices, it uses a time-sharing system using intermittent signals for calling between the parent device and the slave devices. , the problem is that the circuit configuration is complex and noise resistance is low. In addition, in this device, since each child device is connected to the parent device via many common parts including the control line, it is difficult to connect to the common part or to the common part. If a failure occurs in a specific circuit, the failure will not be limited to a specific slave unit, but will affect all slave units. It was unsuitable for use as a communication device with a central monitoring device.

Therefore, it is an object of the present invention to provide a telephone communication device that has a small number of cables between a parent device and a slave device, has a simple circuit configuration, has high noise resistance, and operates reliably.

In order to achieve the above object, the communication device according to the present invention is provided with a selection switch and a selection display circuit for each of the communication base device and the communication slave device on the parent device side,
The slave device is provided with the telephone slave device and a call switch and a connection control circuit for each slave device, and each of the slave devices is connected to the master telephone device via a common audio bus, the telephone device comprising: The selection display circuit and the corresponding connection display circuit are connected by individual control lines, and each selection display circuit includes a resistor and a switching element that is turned on by an attendant call signal from a corresponding call switch. , an indicator that is energized when the switching element is on, and a diode connected in antiparallel to the switching element, and each connection control circuit includes two resistors and a corresponding selection switch. a switching element that is turned on by a communication handset selection signal; a relay that includes a contact and is energized when the switching element is on; and a diode that is connected in antiparallel to the switching element; One of the resistors and the switching element in the circuit, the control line, the diode and the selection switch in the selection display circuit constitute the circuit for the selection signal, and the resistor and the switching element in the selection display circuit and the The control line, a diode in the connection control circuit, the other resistor, and the call switch each constitute a circuit for the call signal, and when the call switch is turned on, the call signal corresponding to the switch is activated. When the circuit for the selection signal is closed and the indication is displayed on the display and the selection switch is turned on, the circuit for the selection signal corresponding to the switch is closed and the relay is energized and the communication terminal is output via the contact. This allows the device to make calls.

The embodiments shown in the drawings will be described below.

In the figure, reference numeral 1 denotes a communication master unit provided in a master device such as a monitoring device, and reference numerals 2a, 2b, . Each of the telephone handsets 2a, 2b...2n is connected to the telephone master unit 1 via relay contacts 4a, 4b...4n and a common voice bus 3.

Selection switches 5a and 5b are provided on the side of the communication master device 1 (parent device side) to select the communication slave device to which a call is to be made.
...5n, and a pair of selection display circuits 6a, 6b...6n are provided for each handset, and on the handset side (slave device side) there are call switches 7a,
A pair of connection control circuits 7b...7n and connection control circuits 8a, 8b...8n is provided for each slave device.

The selection switches 5a, 5b...5n are manual return type switches, and the call switches 7a, 7b...7n
is an automatic return type switch that closes while being pressed down. Each switch 5a, 5b...5n and 7
One terminal of a, 7b, . . . , 7n is commonly connected to the negative terminal of the DC power supply 9.

Connection control circuit 8 for selection display circuits 6a, 6b...6n and corresponding communication handsets 2a, 2b...2n
a, 8b...8n are individual control lines 10a, 10b
...10n, and are commonly connected to the positive terminal and negative terminal of the DC power supply 9 via power lines 11 and 12.

The selection display circuits 6a, 6b...6n display lamps as indicators when a call signal indicating that the call switches 7a, 7b...7n are closed is input via the control lines 10a, 10b...10n. 21, and selection switches 5a, 5b...5
This is a circuit that outputs a selection signal to the control lines 10a, 10b, . photo coupler 20 and this photo coupler
It has a lamp 21 that is energized when turned on, a diode 22 connected in parallel and in the opposite direction to the light emitting part of the photocoupler, and a resistor 23.

When the call switches 7a, 7b...7n are closed, the connection control circuits 8a, 8b...8n output a call signal to the control line indicating that the call switches 7a, 7b...7n are closed, and output a call signal indicating that the selection switches 5a, 5b...5n are closed. This is a circuit that closes the corresponding contacts 4a, 4b...4n when a meaning selection signal is input via the control line to enable the communication handsets 2a, 2b...2n to make a call, one of which is represented by 8a. As shown in the figure, there is a photocoupler 30 as a switching element that is turned on by the selection signal, a relay 31 that is energized when the photocoupler is turned on, and a diode 3 that is connected in parallel and in the opposite direction to the light emitting part of the photocoupler.
2 and two dividing resistors 33 and 34, respectively.

Each circuit element constituting the selection display circuits 6a, 6b...6n and the connection control circuits 8a, 8b...8n includes a resistor 33, a photocoupler 30, and a diode 22.
The selection switch 5a and the selection switch 5a form a closed circuit for a selection signal, and the resistor 23, the photocoupler 20, the diode 32, the resistance 34, and the calling switch 7a form a closed circuit for a calling signal.

Contacts 4a, 4b...4n are normally open contacts of relays 31 provided in corresponding connection control circuits 8a, 8b...8n. In this embodiment, each relay 31 is connected in series with the light emitting part of the photocoupler 30 to the DC power supply 9;
It may be connected in series with the light emitting section.

In this telephone device, when the call switch 7a is pressed down, a resistor 23, a photocoupler 20, a diode 32
A closed circuit including the resistor 34 is closed and the photocoupler 2
Since 0 turns on, lamp 2 of the selection display circuit 6a
1 lights up. When any of the other call switches 7b...7n is pressed down, that call switch 7
A closed circuit for a calling signal formed by the same type of circuit elements of the selection display circuits 6b...6n corresponding to b...7n and the connection control circuits 8b...8n is closed, and the lamp corresponding to the calling switch is lit. Therefore, the staff member can confirm which handset should be enabled for conversation based on the lit lamp.

Also, when the selection switch 5a is closed, the resistor 33,
Since the closed circuit including the photocoupler 30 and the diode 22 is closed and the photocoupler 30 is turned on, the relay 31 in the connection control circuit 8a is energized, the contact 4a is closed, and the communication slave unit 2a is connected to the voice bus 3, allowing communication. Become. Similarly, when the other selection switches 5b, . . . , 5n are closed, the telephone handset corresponding to the switch becomes available for communication.

Further, in the device of the present invention, by providing a resistor 34 in addition to the resistor 33, when the selection switch 5a is turned on with the call switch 7a turned on, the lamp 21 is turned off and the relay 31 is activated preferentially. You can turn it on and make calls. Incidentally, if the resistor 34 is not provided and the switches 7a and 5a are turned on at the same time, both the lamp 21 and the relay 31 will be turned off.

Furthermore, by connecting the photocoupler 20 and diode 22 in antiparallel to the photocoupler 30 and diode 32, it is possible to flow a sufficient current through the lamp 21 and relay 31. That is, if the lamp 21 is
If the lamp 21 is directly connected to the power supply line 11, even if the call switch 7a is turned on, the current flowing through the lamp 21 will also flow through the resistor 33, so that a sufficient lighting current for the lamp 21 will not flow. In the above embodiment,
In particular, by using the photocoupler 20, the voltage applied to the photocoupler 20 can be made constant at about 1 volt, and when the photocoupler 20 has a current transfer rate of 1 or more, the lighting current that is 2 to 3 times higher than that of the lamp 21 is It can be flowed to Further, for the same reason, when the selection switch 5a is turned on, a sufficient current can be passed through the relay 31.

In addition, in the above embodiment, the photocoupler 20,
30 can be replaced with a relay and its contacts. Alternatively, instead of directly energizing the lamp 21 when the photocoupler 20 is turned on, the fact that the photocoupler 20 is turned on may be stored in a flip-flop, and the stored signal may be used to turn on the switch element of the lamp driver to energize the lamp 21. Similarly, instead of energizing the relay 31 directly by the photocoupler 30, the photocoupler 30
The fact that the relay has been turned on may be stored in a flip-flop, and the stored signal may be used to turn on a switch element in the relay's energizing circuit, thereby energizing the relay.

As described above, in the communication device according to the present invention, the selection display circuit on the parent device side and the corresponding connection control circuit are connected to each other by individual control lines. Even if a failure occurs in a specific connection control circuit, the effect of the failure is limited to the failure of an individual slave unit, and all slave units are not affected by the failure. It is suitable as a communication device. In addition, this device operates using continuous signals, has high noise resistance, operates reliably, requires fewer cables between the parent device and the child device, and has a simple circuit configuration. effective. moreover,
The present invention can operate reliably because sufficient current can flow through the display device on the master side corresponding to the call switch and the relay on the slave side corresponding to the selection switch.

[Brief explanation of drawings]

The figure is a block diagram showing an example of the electric circuit of the communication device according to the present invention. 1: Talking master device, 2a, 2b...2n: Talking slave device,
3: Audio bus line, 4a, 4b...4n: Relay contact, 5a, 5b...5n: Selection switch, 6a, 6
b...6n: Selection display circuit, 7a, 7b...7n: Call switch, 8a, 8b...8n: Connection control circuit,
10a, 10b...10n: control line, 20, 30:
Switching element, 21: Display device, 22, 32:
Diode, 23, 33, 34: Resistor, 31: Relay.

Claims (1)

[Claims] 1. On the parent device side, there are a communication master device 1 and a communication slave device 2.
Selection switches 5a, 5b... for each a, 2b...2n
5n and selection display circuits 6a, 6b...6n, and the slave devices 2a, 2b...2n are provided on the slave device side.
and a call switch 7a, 7b...7n and a connection control circuit 8a, for each slave device 2a, 2b...2n.
8b...8n are provided, and each of the talking handsets 2a, 2b...
2n is connected to the communication base unit 1 via a common audio bus 3, and the connection control circuits 8a, 8b...8n corresponding to the selection display circuits 6a, 6b...6n are connected to individual control lines. 10a, 10b...10n, and each selection display circuit 6a, 6b...6n is connected to a resistor 23.
, a switching element 20 that is turned on by an attendant call signal from the corresponding call switch 7a, 7b, 7n, an indicator 21 that is energized when the switching element 20 is on, and an inverse parallel to the switching element 20. Each connection control circuit 8a, 8b...8n has two resistors 33, 34 and a corresponding selection switch 5.
A switching element 30 that is turned on by a communication slave selection signal from a, 5b...5n, and contacts 4a, 4
b...4n and is energized when the switching element 30 is on, and a diode 32 connected in antiparallel to the switching element 30.
One of the resistors 33 and the switching element 30 in the connection control circuits 8a, 8b...8n, the control lines 10a, 10b...10n, and the selection display circuit 6a,
The diodes 22 in 6b...6n and the selection switches 5a, 5b...5n constitute the selection signal circuits, respectively, and the selection display circuits 6a, 6b...6n
The calling signal is generated by the resistor 23 and switching element 20 in the middle, the control lines 10a, 10b...10n, the diode 32 in the connection control circuit 8a, 8b...8n, the other resistor 34, and the calling switch 7a, 7b...7n. When the call switches 7a, 7b...7n are turned on, the call signal circuit corresponding to the switch is closed, and this is displayed on the display 21, When the selection switches 5a, 5b...5n are turned on, the selection signal circuit corresponding to the switch is closed, the relay 31 is energized, and the communication handsets 2a, 2b... are connected via the contacts 4a, 4b...4n.
A communication device characterized in that 2n can be used for communication.