JPH0754952B2 - Network connection control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention branches and switches a line of a telephone network into a plurality of extensions,
The present invention relates to a network connection control device in which a non-telephone type terminal is connected to the extension.

[Conventional technology]

FIG. 3 is a diagram showing an outline of a configuration example of a conventional network connection control device in which the number of lines of the telephone network is 1 and the number of extensions is 3. In this figure, 1 is a line, 2 to 4 are extensions, 5 and 6 are telephones, 7 is an automatic facsimile, 8 is a loop creation circuit, 9 and 10 and 11 are loop monitoring circuits, 12 is a protection circuit, and 13 is a ring generation circuit. Units 14 and 15 are power supplies, and their voltages are + EV and -EV. SW1
Is a ring generator switching relay switch, SW2 to SW4 are extension switching relay switches, and 100 is a control circuit.

Next, the operation will be described.

When an incoming call arrives at the telephone 5 selected beforehand, the telephone 5 captures the line (loops on), and then the control circuit 10
When 0 detects the dial pulse of the telephone 5,
Detects the extension number to be transferred and relay switch SW2, SW1
The ring signal for ringing the bell generated by the ring generator 13 is sent to the designated extension while the telephone line is captured by the loop creating circuit 8 and the extension can be transferred. Has become.

Further, at the time of transmission, when the automatic facsimile 7 loops on, the control circuit 100 turns on the relay switch SW4 and turns off the relay switch SW2 to send a dial pulse or PB to the line 1 connected to the telephone network. It is composed.

In order to confirm the other party's response when the automatic facsimile 7 is transmitted, a method of monitoring the line 1 of the telephone network and detecting the other party's response by reversing the polarity is generally used.

[Problems to be solved by the invention]

However, with such a detection method, the automatic facsimile 7
When a call is made when the polarity of the voltage in the normal state and the polarity of the voltage sent from the telephone network line 1 do not match, the polarity is reversed just by capturing the line 1, so dialing from the automatic facsimile 7 There is a case where the partner response cannot be normally detected even if the polarity is inverted again at the partner response after the pulse is sent.

In order to eliminate such a problem, the polarity of the line 1 and the voltage (-E) of the power supply 15 inside the network connection control device of FIG.
It was necessary to connect to line 1 during the installation work so that it would match V).

Also, some automatic facsimiles define the polarity of the voltage of the line to be connected. In that case, line 1
After matching the polarities of the voltages of and, it is also necessary to match the polarities of the extension 4 and the defined polarities of the line side of the automatic facsimile 7, which further complicates the work during installation work. was there.

The present invention has been made to solve such a problem, and makes the polarity of the DC voltage obtained from the line of the telephone network coincide with the polarity inside the network connection control device without performing complicated construction, An object of the present invention is to obtain a network connection control device that normally operates a connected terminal such as a facsimile.

[Means for solving problems]

The network connection control device according to the present invention includes a polarity detection circuit for detecting the polarity of a voltage transmitted from a line, a polarity matching circuit for inverting the polarity of a voltage transmitted from a line, and a polarity detected by the polarity detection circuit. And a control circuit for connecting the line and the terminal after the polarity matching circuit is operated when the polarity of the voltage applied to the terminal is different in the network connection control device.

[Action]

In the present invention, when the polarity of the voltage sent from the line detected by the polarity detection circuit and the polarity of the voltage applied to the terminal are different, the control circuit controls the voltage sent from the line by the polarity matching circuit. After reversing the polarity, connect the line and the terminal.

〔Example〕

FIG. 1 is a diagram showing the configuration of an embodiment of the network connection control device of the present invention. In this figure, the same symbols as those in FIG. 3 indicate the same parts, 16 is an incoming detection circuit, 17 is a polarity detection circuit,
Reference numeral 18 is an external incoming call selection switch, SW5 to SW7 are extension switch relay switches, SW8 is a polarity switch relay switch that is a polarity matching circuit, and 200 is a control circuit.

Next, the operation will be described.

When the power is turned on, or the incoming call detection circuit 16 does not detect an incoming call, and the loop monitoring circuits 9 to 11 are connected to the extensions 2 to 4, the telephones 5 and 6 and the automatic facsimile 7 do not capture the extension ( Loop off) Control circuit 20 when empty
0 indicates that the polarity of the voltage of the line 1 is detected by the polarity detection circuit 17, and if this polarity is different from the polarity of the voltage (−EV) of the power supply 15 that supplies the loop current to the extension lines 2 to 4, The polarity of the voltage of the line 1 is reversed by the relay switch SW8 so that these polarities are matched in advance.

Next, when a call is made by the facsimile 7 connected to the extension 4, the control circuit 200 detects that the loop-on by the loop current supplied by the voltage (−EV) of the power supply 15 is the loop monitoring circuit 11
For example, determine whether 100ms is detected,
If ms is detected, the relay switch SW7 is turned on to capture the line 1 of the telephone network. At this time, the voltage applied to the automatic facsimile 7 is switched from the voltage (-EV) of the power source 15 to the voltage of the telephone network sent from the line 1, but since the polarity is previously matched by the relay switch SW8, The polarity does not reverse when capturing line 1,
Dialing from the automatic facsimile 7 becomes possible. After that, the automatic facsimile 7 sends a predetermined modem signal (CNG) by detecting the polarity inversion from the telephone network after dialing by the polarity detection circuit 17.

When the extension 4 is selected while the incoming call from the telephone network is switched to the extension lines 2, 3 and 4 by the incoming call selection switch 18 provided externally, the network connection control device of FIG. When the detection circuit 16 detects the incoming call (the polarity is reversed at this time), the control circuit 200 turns on the relay switch SW7 to send the ring signal from the telephone network to the extension line 4. At this time, since the polarity of the telephone network is adjusted by the relay switch SW8 when the telephone network is in an empty state, the extension 4 has a polarity inversion state.

Also, for example, there is an incoming call on the telephone 5 and after the call (the telephone 5
When the answer is, the polarity of the network returns to the original). When the automatic facsimile 7 receives the call by extension transfer to make a manual call, the dial pulse for switching the connection to the extension 4 is sent, When this is detected by the loop monitoring circuit 9, the control circuit 200 causes the loop creating circuit 8 to capture the line 1 of the telephone network, and the relay switch SW1 is turned on to the ring generator 13 side for a call. Relay switch SW5 is off and relay switch SW7 is on. When this switching is performed, the ring signal generated by the ring generator 13 is sent to the automatic facsimile 7 and the incoming call is made. Then, when the loop is turned on in the automatic facsimile 7, the loop monitoring circuit 11
Thus, loop-on is detected, and the control circuit 200 restores the relay switch SW1. In this case, the series of operations related to the voltage (−EV) of the power supply 15 and the voltage (+ EV) of the power supply 14 obtained by switching the relay switch SW7 are
Since the voltage (-EV) of the power supply 15 and the voltage polarity of the line 1 are already matched by 8, the same operation as the polarity change at the time of an incoming call from the ordinary telephone network is performed on the extension 4.

That is, in the operation of receiving a call from the line 1, the polarity is temporarily reversed when a call is received and a ring signal is transmitted. At this time, the non-telephone terminal detects the call and responds by looping on, and the telephone network side responds by the response. The polarity is restored (that is, the voltage (−EV) of the power supply 15). However, in this case, the voltage of the power supply 15 (-EV) is changed by the relay switch SW8.
Since the polarity of line 1 and line 1 have already matched, the voltage (+ EV) of power supply 14 when the ring is generated by ring generator 13 has polarity inversion, and when relay switch SW1 is switched (returned to its original state). Since the same polarity as the voltage (-EV) of the power supply 15 is sent from the network, the same operation as the incoming operation from the line 1 can be obtained.

Therefore, even when a non-telephone terminal such as an automatic facsimile 7 that monitors the polarity of the voltage and performs a predetermined operation is connected to the extension 4 in the call origination / termination operation, the same operation as the polarity change of the voltage of the telephone network is performed. Therefore, it is possible to stably operate the connected terminal without malfunctioning.

In the present invention, mainly an incoming call detection circuit 16, a polarity detection circuit 17, a relay switch SW1, which is used for polarity detection,
Extension switch relay switches SW5 to 7, relay switch SW
By providing the incoming call selection switch 18, the network connection control device of the present invention can be easily realized.

FIG. 2 is a diagram showing the outline of the configuration of another embodiment of the present invention corresponding to a plurality of lines. In this figure, the same reference numerals as those in FIG. 1 indicate the same parts, 1a and 1b are lines, and 12
a and 12b are protection circuits, 13a and 13b are ring generators, 14a and 14b are power supplies, and 19a and 19b are NCUs, which are composed of an incoming call detection circuit, a polarity detection circuit, and a loop creation circuit. SW1a and SW1b are relay switches for switching ring generators, SW8a and SW8b are relay switches for polarity switching, and SW9 is a line selection relay switch. Further, 300 is a control circuit.

In this embodiment, the number of lines of the telephone network is two and the number of extensions is three, and the voltage polarity can be matched by the relay switch SW8a or SW8b as in the embodiment shown in FIG.

In the above embodiment, the case where the number of lines of the telephone network is 2 or less is shown. However, by increasing the number of NCUs, relay switches and the like according to the number of lines, a network connection control device having a telephone network of 3 lines or more is also available. The same effect can be obtained.

Further, in the above embodiment, the case where the extension transfer is performed by the dial pulse has been described, but the same applies to the case where the extension transfer is performed by the PB signal.

〔The invention's effect〕

As described above, according to the present invention, the polarity detection circuit that detects the polarity of the voltage transmitted from the line, the polarity matching circuit that inverts the polarity of the voltage transmitted from the line, and the extension to be received among the plurality of extensions are selected. Incoming call selection switch to
When the polarity of the voltage sent from the line detected by the polarity detection circuit and the polarity of the internal power supply voltage applied to the terminal connected to the extension selected by the incoming call selection switch in the network connection control device are different, the polarities match. While the circuit is operating and the polarities are matched, the loop is created by the loop creation circuit, and the ring generator calls the terminal connected to the extension while applying a voltage of the opposite polarity to the voltage applied to this terminal. Since a control circuit for connecting the line and the terminal is provided, the extension to be received among the plurality of extensions can be freely selected by the incoming call selection switch, and the polarity opposite to the voltage applied to the terminal by connecting the ring generator. Since the voltage is applied, the same state as when the line is polarized can be obtained, and therefore terminals for various applications such as personal computers and facsimiles may malfunction due to polarity mismatch. No, there is an effect that it is possible to operate reliably.

Further, according to the present invention, a plurality of extension lines are connected to a non-telephone system, that is, a device such as an automatic facsimile machine that performs a predetermined operation after monitoring the detection of voltage and matching the polarities in the operation of making and receiving a call. However, since the same operation as the polarity change of the voltage of the telephone equipment can be obtained by the operation of the polarity matching circuit, it is possible to operate stably without causing a malfunction.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a network connection control device of the present invention, FIG. 2 is a diagram showing an outline of a configuration of another embodiment of the present invention, and FIG. 3 is a conventional network connection control device. It is a figure which shows the outline of a structure. In the figure, 1, 1a and 1b are lines, 2 to 4 are extensions, 5 and 6 are telephones,
7 is an automatic facsimile, 8 is a loop creating circuit, 9, 10, 11
Is a loop monitoring circuit, 12,12a, 12b is a protection circuit, 13,13a, 13b
Is a ring generator, 14, 14a, 14b and 15 are power supplies, 16 is an incoming call detection circuit, 17 is a polarity detection circuit, 18 is an incoming call selection switch, 19a,
19b is NCU, SW1, SW1a, SW1b, SW5, SW6, SW7, SW8a, SW8b, SW9
Is a relay switch.

Claims (1)

[Claims] 1. A telephone network line is branched into a plurality of extensions for accommodating a plurality of telephone and non-telephone terminals, and the line is captured by a loop creating circuit when an incoming call is received, and the extension is selected in advance. When a call is received and a transfer operation is performed, a ring signal is sent from a ring generator to a predetermined extension of the plurality of extensions, and a non-telephone type terminal that operates by monitoring the polarity of the voltage of the extension is connected to the line. In the network connection control device, a polarity detection circuit that detects the polarity of the voltage transmitted from the line, a polarity matching circuit that inverts the polarity of the voltage transmitted from the line, and An incoming call selection switch for selecting an extension to receive an incoming call, a polarity of the voltage transmitted from the line detected by the polarity detection circuit, and a terminal connected to the extension selected by the incoming call selection switch in the network connection control device. When the polarity of the internal power supply voltage applied to is different and the polarity matching circuit is operated to match the polarities, the loop creation circuit captures the line and the telephone terminal once receives the call. According to the transfer operation information to the non-telephone type terminal, the ring generator is activated to call while applying a voltage having a polarity opposite to that of the voltage applied to the non-telephone type terminal, and the line and the non-telephone type terminal are called. A network connection control device comprising: a control circuit for connecting to a terminal;