JPH0227880B2 - BOTANDENWASOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a button telephone device capable of making telephone calls over a central office line and making extension calls.

2. Description of the Related Art In general, a key telephone device is composed of a main device connected to a central office line and a plurality of key telephones connected to the main unit, and is configured to allow both central office line calls and extension calls.

Problems to be Solved by the Invention However, all conventional button telephone devices of this type have a central office line communication path for conducting central office line calls between the main unit and each button telephone, and an extension line communication path. There were problems in that a large number of wiring cables were required, such as an extension line for communication and a signal transmission line for transmitting various other data, and the internal circuit configuration of the main unit and each button telephone was relatively complex.

On the other hand, the central office line communication path for making office line calls and the internal line communication path for making internal calls are mutually shared,
There are some models that reduce the number of wiring cables, but with these types, the call loss during calls to the central office line is considerably greater than the call loss during internal calls.
There was an inconvenience that if the normal speech level was set during an extension call, the speech level would be very low during a central office call.

The present invention eliminates the above-mentioned drawbacks of the conventional technology, and has the advantage of reducing the number of wiring cables with a simple configuration, and allowing calls to be made at almost the same speech level whether talking to an internal line or a central office line. The object of the present invention is to provide a button telephone device that provides a button telephone device.

Means for Solving the Problems In order to achieve the above object, the present invention provides a pair of wires connected between a main device and a key telephone for transmitting voice communication for a central office line communication line, an extension communication line, and an extension call. Use the other pair of wires as power wires,
It is configured to be used as a blinking signal line for each of the office line indicator lamp and extension line indicator lamp, and as a signal transmission path for various data, and the above pair of wires can be used as the office line communication line and as the extension line communication line. The polarity is reversed when using the diode, and the diode connected between the above pair of wires is reverse biased during a call on the central office line, and the call loss caused by the diode during an internal call is reduced during a call on the central office line. This is configured so that the call loss is greater than the above-mentioned call loss.

Therefore, according to the present invention, when there is only one central office line to be accommodated, two pairs of wiring are sufficient, and the number of wiring cables is significantly less than that of the conventional system. Since the system is configured so that the call loss is greater than when making an outside line call, it has the effect that calls can be made at approximately the same level during any call.

Embodiment The figure is a schematic configuration diagram of an embodiment of the button telephone device of the present invention.

In the figure, 1 is the main device, 2 is a button telephone,
T, R, H and E are each distribution cables. Wiring cables T, R, H, and E are used to connect the main device 1 and a plurality of key telephones 2 in parallel. T and R are for voice transmission for a central office line communication line, an extension line communication line, or an extension call. In the case of a central office line, T is - and R is +, and in the case of an extension line, T is + and R is -. Here, the wiring T,
The reason why the polarity of R is reversed when making a call to the office line and when talking to an extension line or calling an extension line is as follows.
That is, when making a telephone call over a local office line, the distance to the other party is significantly greater than when making an extension telephone call. Therefore, if you set the call so that the call loss is the same for both the central office line call and the extension call, if you set it so that the call loss is the same for both the central office line call and the extension call, if you set it so that the call loss is the same for the central office line call and for the extension call, then When making a call, the level is too high and it is difficult to talk, and conversely, if you make it possible to talk at an appropriate level when making an extension call, the level is too low and you cannot make a call when talking to a local office line. A problem arises. For this reason, it is necessary to reduce call loss when talking to a central office line than when talking to an extension line, and to be able to communicate at an appropriate level during any call. In this embodiment, the polarities of the wires T and R are reversed between the central office line call and the extension line call in order to switch over the above-mentioned call loss. Specifically, it operates as follows.

First, during an extension call, the wire T is + and the wire R is -, and in this case, the circuits T ₂₀ and R ₂₀ that constitute the voice transmission path for the extension call are connected to the wires T and R via the diode D ₂₀ . Although they are connected and cause a relatively large call loss, during a central office line call, the wire T becomes negative and the wire R becomes positive, making the diode _D20 reverse biased and disconnecting the circuits _T20 and _R20 from the wires T and R. Therefore, when making a call on the local line, there is significantly less call loss than when making a call on the internal line, and it becomes possible to talk at an appropriate level for both the internal line and the local line.

H and E are the power supply line and the communication line for the office line or the transmission line for the blinking signal of the extension indicator lamp and the transmission line for the data signal that controls this device, and the voltage is 8V when in standby, 16V when talking on the extension line,
It is 24V when talking on a central office line. Data signals include station line acquisition, station line hold, and individual extension signals. 10 is an incoming call detection circuit. Reference numeral 11 denotes a data transmission/reception control circuit for the main device, which receives data signals from the telephone, controls the main device, and transmits information from the main device to the telephone. L ₁ and L ₂ are office lines, D ₁₀ to _{D 13} are diodes, and the polarity of the office lines is such that T is - and R is +. _T10 is the extension current supply transformer, OSC is the office line incoming sound source, and T, R is connected via _T10 .
A ringtone is sent to the distribution cable. B is, for example, a 24V power supply, and C ₁₀ and R ₁₀ are a capacitor and a resistor for removing internal line ripples. R ₁₁ , R ₁₂ , and Q ₁₀ are a resistor and a transistor for detecting an extension call. When the button telephone goes off hook (OFF HOOK), transistor Q ₁₀ turns on, and in the on hook (ON HOOK) state, transistor Q 10 turns on. Since the resistor R ₂₀ through which a slight current flows through the route has a high resistance, the transistor Q ₁₀ is not turned on. Z ₁₀ is an approximately 16V tuner diode, and during an internal call, transistor Q ₁₀ is ON, so
Set the H line to about 16V. Transistor Q ₁₁ is ON during standby, during extension calls, and during calls to the central office line.
OFF, repeats ON and OFF when a call is received or on hold. ZD ₁₁ is an approximately 8V tuner diode, and when transistor Q ₁₁ is ON, it sets the voltage on the H line to approximately 8V. R ₁₃ and Q ₁₂ are H line voltage control resistors and transistors, CH ₁₀ is a chiyoke transformer,
Its role is to increase the impedance of the power supply circuit to data communication signals.

HS ₁ and HS ₂ are switch switches, AMP is an amplifier,
SP is a speaker, 20 is a telephone network, and D ₂₀ is a diode. R ₂₀ and T ₂₀ are resistors and transformers,
This is a circuit for receiving calls from the central office line and calling extensions.The input from here is amplified and the sound is amplified from the speaker SP.
CH ₂₀ is a chiyoke transformer, and 21 is a constant voltage circuit for the telephone. Reference numeral 22 denotes a lamp display circuit that blinks the station line display lamp L ₂₀ or the extension line display lamp L ₂₁ according to the voltage of the H line. In other words, at 8V during standby, both lamps L ₂₀ and L ₂₁ are off, at 16V during an extension call, only lamp L ₂₁ is on, and at 24V during a central office line call, the lamp is turned off.
Only L ₂₂ is turned on. 23 is a data transmission/reception control circuit on the key telephone side, which receives data signals from the main device or other key telephones and controls the amplifier AMP, as well as making calls to the local telephone, holding the central telephone, and calling other key telephones. It has the role of sending out signals to the main unit and other key telephones.
24 is equipped with a central office line button, a central office line hold button, and an extension individual call button, and a data transmission/reception control circuit 23 that sends signals for calling the central line, holding the central line, and calling other button telephones.
25 is a terminal for setting a self number.

Next, the operation of the button telephone device having the above configuration will be explained with reference to the drawings.

(1) Incoming call from the office line When an incoming signal comes from the lines L ₁ and L ₂ , the incoming call detection circuit 10 detects it, operates the office line incoming sound source OSC, and the data transmission/reception control circuit 11 receives the data signal of the incoming office line. Send. The signal from the office line incoming sound source OSC is input to the amplifier AMP via the T and R lines, a diode D ₂₀ , a resistor R ₂₀ and a transformer T ₂₀ . The data signal is read by the data transmission/reception control circuit 23, and the data transmission/reception control circuit 23 turns on the amplifier AMP, causing the speaker SP to sound to notify the incoming call on the central office line. Also, turn on and off transistor _Q11 ,
Make the station line indicator lamp L ₂₀ blink.

(2) Office line response, office line origination, telephone call When the office line button 24 is pressed to turn OFF HOOK, a data signal is sent from the data transmission/reception control circuit 23 to the data transmission/reception control circuit 11 on the main device side. The data transmission/reception control circuit 11 on the side reads it and restores the relay A. The office lines L ₁ and L ₂ are connected to the T and R lines, forming a DC loop with the telephone switch HS and the telephone circuit network 20, and the office lines are captured and used for answering, talking, or making calls. Or turn on transistor Q ₁₁ and leave L ₂₀ lit.

(3) Office line hold When the office line hold button on the key matrix 24 is pressed during a call on the office line, data is sent from the data transmission/reception control circuit 23 on the key telephone side to the main unit, and the data is sent to the main unit by the transmission/reception control circuit 11 on the main equipment side. Read and operate relay H to continue the station line loop, turn on and off transistor _Q11 , and blink the station line indicator lamp _L20 . At this time, relay A is restored.

(4) Release hold, call button Press the office line button on the key matrix 24 of the telephone 2 to turn off the hold.
HOOK) Then, the same operation as the central line response described in (2) will result in a central telephone call state. At this time, relay H is restored.

(5) End of local line Turn handset on hook (ON HOOK)
Then, the information is read by the data transmission/reception control circuit 23 on the button telephone side, and a data signal is sent from the button telephone 2 to the H line.

This information is read by the data transmission/reception control circuit 11 on the main device side of the main device 1, and the relay A is restored. Also, the transistor _Q10 is turned ON, and the H line is connected to the
Set to standby state as 8V.

(6) To make an extension call, raise the handset of button telephone 2.
HS ₁ turns on and main device 1 Current flows through the route and transistor _Q10 turns on.
do.

When the transistor Q ₁₀ turns on, the H line becomes approximately 16V due to the action of the Zener diode ZD ₁₀ , which is applied to the lamp display circuit 2 of the button telephone 2.
2 and lights up the extension indicator lamp _L21 .

Next, one of the extension individual call buttons on key matrix 24 is pressed. Then, the call information is sent to other key telephones through the H line. The other key telephones read the information using the data transmission/reception control circuit 23 on the telephone side, and determine whether the self-key telephone set by the self-number setting terminal 25 is being called, and if so, the key telephone ( the amplifier of the called button telephone
Turn it on.

When a voice call signal is sent from the telephone circuit network 20 of the button telephone set through HS ₁ between the T and R lines, the voice is transmitted to the D ₂₀ -R ₂₀ -T ₂₀ of the key telephone set.
-Amplifier AMP-Speaker SP route is amplified and the sound is amplified from speaker SP to make a call.

(7) Extension answer, call When the called telephone raises the hand set,
HS ₁ HS ₂ is turned ON, and the amplifier AMP is turned OFF by the data transmission/reception control circuit 23 on the button telephone side.

The telephone network 20 of the called telephone is also operational, and an extension conversation can be made with the calling party through T, R, etc.

(8) Ending an extension When the calling button telephone and the called button telephone turn ON HOOK, transistor Q ₁₀ turns OFF, transistor Q ₁₁ turns ON,
The H line will be about 8V and will be in standby mode.

Effects of the Invention As described above, the present invention uses one pair of wiring cables as a central office line communication line, an extension line communication line, or a voice transmission line for extension calling, and connects the other pair of power supply lines and office line communication line, or To realize a button telephone device capable of accommodating one station line with 4-wire (2 pairs) multi-wiring with a simple circuit configuration by transmitting a blinking signal of an extension indicator lamp and using it as a transmission path for a data signal to control this device. This greatly improves workability and can be provided at low cost. According to the present invention, a diode is connected between a pair of wires used as an extension line communication path and a central office line communication line, and the polarity of the wiring is set to be opposite to each other during an internal line communication and a central office line communication. The above diode is forward-biased when making an internal call, and the diode is reverse-biased when making a call to a central office line, so the call loss due to the diode is greater during an internal call than when making a call to a central office line. This has the effect that the call level can be made almost the same during any call.

[Brief explanation of drawings]

The figure is a block wiring diagram of the main unit of the button telephone device and the button telephone in one embodiment of the present invention. 1... Main device, 2... Key telephone, 10...
Incoming call detection circuit, 11... data transmission/reception control circuit for main device, 20... telephone circuit network, 21... constant voltage power supply, 22... lamp display circuit, 23... data transmission/reception control circuit for button telephone side.

Claims (1)

[Claims] 1. A first pair of wires connected between the main device and the key telephone and used as a central office line communication path, an extension communication path, and a voice transmission path for calling an extension; A second pair of wiring is connected between the two and is used as a blinking signal line for each of the power supply line, office line indicator lamp, and extension indicator lamp, and as a signal transmission path for various data, and the first pair of wiring is used as an extension line communication line. a changeover switch means for switching the polarity to be reversed when used as a central office line communication line, and a series circuit of a resistor and a diode connected between the first pair of wiring lines; The diodes constituting the series circuit are biased by the first pair of wires in the reverse direction during a call on the local line and in the forward direction during a call on the internal line, thereby reducing the call loss during the internal line call. A button telephone device configured to have greater call loss than the above-mentioned call loss.