JPS62298298A - Telephone system - Google Patents

Abstract

PURPOSE:To eliminate necessity of installing a feeding circuit exclusively used for a communication terminal equipment in a main unit and make it possible to connect the communication terminal equipment to the main unit using simple constitution by starting a talking terminal equipment such as a facsimile unit, etc.,by extension call and operating by station power ource after starting. CONSTITUTION:Main wire/extension switching relays 21 and 22 are normally switched to extension side. Incoming signals from a trunk line 1 are detected by a detecting circuit 23, and a control signal for generating incoming tone is sent from a controlling circuit 28 to a key telephone set 5. When a user makes a reply by off-hook, the switching relay becomes trunk line side and becomes the state of call. However, in case of call of a facsimile unit 9, extension number of the facsimile unit is dialed holding the trunk line in a holding circuit 20. Then, the controlling circuit 28 sends a control signal to an incoming signal generator 81 and inputs an incoming signal of 20 Hz through a change- over switch 80, and the facsimile unit replies at once by automatic off-book operation. When a user of the key telephone 5 makes on-hook, the switching relay 21 is switched to the trunk line side, and the trunk line held in a holding circuit 26 is connected to the facsimile unit 9.

Description

[Detailed description of the invention] 3. Detailed description of the invention [Object of the invention 1 (Industrial application field) The present invention relates to a telephone device.

(Prior Art) In general, what is called a button telephone device includes a main device connected to a central office line, and a plurality of devices connected to the terminal connection section of the main device via control signal lines and voice signal lines. The phone consists of a button and a condyle.

(Problem to be Solved by the Invention) However, when connecting a facsimile machine, for example, as a terminal device of the main device, conventionally, when transferring a facsimile call received by a button telephone to the facsimile machine, an incoming signal generator is required. Like a normal exchange, the telephone interface circuit of the facsimile machine was operated by the power supply circuit installed in the main unit even when a call was being made with the central office line, so the connection between the central office line and the central office line was This type of button telephone device, which uses the central office power supply during a call, requires a dedicated power supply circuit for the facsimile device, which has the problem of making the structure complicated and expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a button telephone device that has a simple and inexpensive configuration and can be connected to a communication terminal device such as a facsimile machine.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a changeover switch that switches a communication terminal device such as a facsimile machine between an extension line side and a central office line side, and a switch that switches a communication terminal device such as a facsimile machine between an extension side and an office line side, and It is equipped with an incoming signal generator that generates an incoming frequency signal and inputs it to the communication terminal equipment, and a central office line hold circuit that keeps the central office line connected. After the state is put on hold by the central office line holding circuit, an incoming call signal of a predetermined frequency is generated from the incoming signal generator and inputted to the communication terminal equipment by an extension calling operation from the key telephone to the communication terminal equipment, and the incoming call signal is In response to a response, the changeover switch is switched to the central office line side to cancel the central office line hold state, and when setting an incoming call from the central office line, an incoming call signal from the central office line is directly input.

(Function) The communication terminal device is activated by an extension call after the button telephone Peng puts the central office line on hold, and after the response, the button telephone goes on-hook, and the central office line that was on hold is connected to the communication terminal device. .

Therefore, when communicating with a central office line, the central office power source can be used, and the communication terminal device can be easily connected using only a conventional power supply circuit that is only used during extension calls.

(Embodiment) FIG. 1 is a circuit diagram showing an embodiment of the present invention, in which the central line 1
is connected to the main device 2. The main device 2 is connected to a button telephone 5 via a call signal line 3 and a control signal line 4, and to an incoming signal switching circuit 8 via a call signal line 6 and a control signal line 7. The incoming signal switching circuit 8 is activated by a control signal given from the main device 2 via a control signal line 7 and a changeover switch 80 that selectively connects a facsimile device 9 to an extension line side or a central office line side, which will be described later. 20H2) and an incoming signal generator 81 that generates an incoming signal and inputs it to the facsimile machine 9 when the switch 8o is in the extension switching state, and the movable side contact output of the changeover switch 19 is connected to the facsimile machine 9. .

On the other hand, inside the main device 2, a central office line holding circuit 20°, a central office line/extension line switching relay 21 and 222, an incoming signal detection circuit 23, which detects an incoming signal from the central office line 1, and an on/off hook response of the facsimile machine 9 are detected. hook detection circuit 24.
Similarly, a hook detection circuit 25 detects the on/off hook response of the button telephone 5. An extension power supply circuit 26 that supplies power during an extension call to the key telephone 5 and facsimile machine 9 through switching relays 21 and 22 switched to the extension side. Data transformer 27 for transmitting and receiving control signals to and from the button telephone 5. It is constituted by a control circuit 28 that controls each part in the main device, and controls the extension exchange connection operation and the exchange connection operation between the central office line and the extension line.

FIG. 2 is a circuit diagram showing the detailed configuration of the incoming signal switching circuit 8. When the control signal line is input, the incoming signal generator 81
The oscillator control circuit 810 within starts the oscillator 811,
20H2 incoming signal is generated. At the same time, control signal line 8
12 to generate a control signal as shown in FIG. 3(a),
Switch the changeover switch 80 to the extension side (opposite side to that shown). Next, an amplifier 8 connected in parallel to the output of the oscillator 811
13.814 is activated and the incoming call signal of 20H2 is input to the extension side fixed contact of the changeover switch 80. As a result, the incoming call signal of 20H2 generated from the oscillator 811 is input to the facsimile machine 9 through the changeover switch 80, and the facsimile machine 9 shifts to the incoming call response operation.

Here, amplifiers 813 and 814 are configured to operate complementary to the incoming signal generated from oscillator 811;
Moreover, the switching timing of the changeover switch 80 is as shown in FIG.
As shown in b) and (c), the amplified outputs are controlled by the oscillator control circuit 810 so that they are both at the same potential for time t. This suppresses noise at the switching timing of the changeover switch 80. Note that a noise prevention resistor 800 of approximately TOMΩ is connected to one movable contact of the changeover switch 8Q.

In the above configuration, central line/extension line switching rules 21 and 22
is normally switched to the extension side. In this state, station line 1
When an incoming signal arrives from the button telephone handle 5 or the facsimile machine 9, this incoming signal is detected by the detection circuit 23. When the detection circuit 23 detects an incoming signal, it inputs the detection signal to the control circuit 28 . Then, the control circuit 28 sends a control signal to the button telephone 5 via the control signal line 4 to generate a ring tone. This results in
A ring tone is generated from the button telephone 5.

Therefore, when the user responds to this ringtone by going off-hook, the switching relay 13 is switched to the central office line side and the call state is established. However, if the call is to the facsimile machine 9, the central telephone line is switched off by holding the central telephone line. Dial the extension number of the facsimile machine 9 while keeping it on hold in the hold circuit 26. Then, the control circuit 28 outputs @ through the control signal line 7.
A control signal is sent to the double signal generator 81 to generate an incoming signal of 20H2. At this time, the selector switch 80 is normally switched to the extension side, and the facsimile
9 is set to automatic response mode.

Therefore, when an incoming signal of 20H2 is generated from the incoming signal generator 81, the incoming signal is transferred to the changeover switch 8.
0 to the facsimile machine 9, the facsimile machine 9 responds immediately with an automatic off-hook operation. Therefore, when the user of the button telephone 5 goes on-hook, the switching relay 21 is switched to the central office line side under the control of the control circuit 28.

As a result, the central office line held in the holding circuit 26 is connected to the facsimile machine 9, and a response signal from the facsimile machine 9 is sent to the calling party. A facsimile signal is received by facsimile machine 9.

Incidentally, at night or the like, by switching the switching relay 12 and the switching switch 80 to the central office line side, the incoming signal from the office @1 is directly input to the facsimile machine 9.

In this embodiment, a facsimile machine is taken as an example of a terminal device connected to the main device 2, but other communication terminal devices having a built-in telephone interface circuit can be connected in exactly the same manner.

[Effects of the Invention] As explained above, according to the present invention, a telephone terminal device such as a facsimile machine is activated by a private information call, and after activation, it is operated by the station power supply. There is no need to provide a power supply circuit, and a communication terminal device such as a facsimile machine can be connected to the main device with a simple and inexpensive configuration.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing one embodiment of the present invention, and Fig. 2 is a circuit diagram showing an embodiment of the present invention.
FIG. 3 is a circuit diagram showing the detailed circuit configuration of the incoming signal switching circuit shown in FIG. 2, and FIG. 3 is a time chart showing waveforms of various parts of the incoming signal switching circuit shown in FIG. DESCRIPTION OF SYMBOLS 1... Office line, 2... Main device, 5... Individual key telephone, 8... Incoming signal switching circuit, 9... Facsimile machine, 20... Office line holding circuit, 21.22 ...central line/
Extension switching relay, 23... Incoming signal detection circuit, 24.
25... Hook detection circuit, 28... Control circuit, 80
... Selector switch, 81 ... Incoming signal optical generation type, 81
0... Oscillator control circuit, 813, 814... Amplifier.

Claims (3)

[Claims] (1) A button telephone and a communication terminal device having a telephone interface are connected, and an internal line exchange connection is made between these button telephone communication terminal devices and an outside line exchange connection is made between the button telephone or communication terminal device and a central office line. A telephone device equipped with a main device, comprising: a changeover switch that switches the communication terminal device between an extension line side and a central office line side; an incoming signal generator that generates an incoming signal of a predetermined frequency and inputs it to the communication terminal device; and a central office line side. When a call is transferred from a key telephone, the connection to the office line is put on hold by the office line holding circuit, and then the extension call is made from the key telephone to the communication terminal device. By operation, the incoming signal generator generates an incoming signal of a predetermined frequency and inputs it to the communication terminal device, and in response to the incoming signal, switches and connects the changeover switch to the central office line side to release the central line holding state, A telephone device characterized in that when setting an incoming call from the office line, an incoming call signal from the office line is directly input. (2) The telephone device according to claim 1, wherein the incoming call signal generator is driven after reducing the voltage between the terminals of the changeover switch when switching the changeover switch to the extension side. (3) The telephone device according to claim 1, wherein the changeover switch has a high resistance between its terminals for noise prevention.