JPH01103057A - Automatic calling network controlling device - Google Patents

Abstract

PURPOSE:To prevent undesired holding of a telephone line by detecting the occurrence of line interruption state in the course of talking and allowing a forced line opening means to open forcibly the telephone line at the detection. CONSTITUTION:When a telephone line is cut off, lines L1, L2 are both at OV, and light emitting diodes 16, 17 are both extinguished and photocouplers 13, 14 are both turned off and detection signals LA, LB go both to logical H level. It is discriminates as the line interruption, relay contacts 9, 5 are opened to complete the operation. When electric non-connection between an automatic call network controlling device and the telephone line or open line by an opposite device is detected during communication, since the line is opened as the line interruption, undesired telephone line holding or consumed communication control time is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic calling network control device that automatically calls 15 by specifying the number of the other party.

[Prior Art] FIG. 2 is a circuit diagram showing an example of the configuration of a conventional automatic calling network control device, each component of which is housed in a telephone set.

20 In FIG. 2, one winding 1a of the hybrid transformer 1 is a modulator/demodulator (not shown) that has a four-wire configuration and mutually converts an audio signal and its modulation signal.
The other winding 1b has a two-wire configuration and captures the telephone lines L1 and L2 at the terminals T1 and T2. Note that a balance circuit 2 is connected to one winding 1a.

The incoming call detection unit 3 detects incoming calls from the telephone lines L1 and L2. The dial pulse sending unit 4 closes the dial pulse sending relay contact 5 by relay operation when the destination number is specified, and connects the telephone lines L1 and L2.
is captured in a loop. In addition, when the captured telephone lines L1 and L2 are dial palace lines, relay contact 5 is activated according to the destination number by relay operation.
The dial pulse is sent out by opening and closing the dial. Note that a series circuit of a resistor 6 and a capacitor 7 forming a spark killer circuit is connected in parallel to the relay contact 5. The bushing pulse sending unit 8 is connected to the telephone lines L1 and L2 via the transformer 1, and sends out bushing pulses corresponding to the destination number when the captured telephone lines L1 and L2 are bushing pulse lines.

The line connection relay contact 9 normally short-circuits the lines L1 and L2 of the transformer 1 (this is called open), and the bushing pulse sending unit 8 sends bushing pulses using a separately provided relay circuit. The relay contact 5 is short-circuited (this is called closing) when the communication is in progress and when communication is in progress.

The response detection section 10 detects a response by detecting that the polarities of the lines L1 and L2 have been reversed or that an answer tone has arrived.

FIG. 3 is an operation flowchart of the conventional device shown in FIG. 2, in which a control section (not shown) starts a series of controls in response to designation of a destination number. First, the dial pulse sending relay contact 5 is closed to put the lines L1 and L2 into a loop state (
Step 101), and waits for 3 seconds for a beep to confirm line connection (Step 102). Next, the types of connected telephone lines L1 and L2 are determined (step 10).
3).

When telephone lines L1 and L2 are dial pulse lines,
The relay operation of the dial pulse sending unit 4 opens and closes the relay contacts 5 according to the destination number to send out dial pulses (step 104).

On the other hand, in the case of a bush pulse line, after closing the relay contact 9 (step 105), the bush pulse sending unit 8 sends out a bush pulse corresponding to the destination number (step 106).

After that, the response detection unit 10 inverts the polarity of the lines L1 and L2,
Alternatively, it waits for the answer tone of 2100 (H2) to be detected (Steps 107 and 113), and when the other party's response is detected, the relay contact 9 is closed and lines L1 and L2 are connected to the modulation/demodulation section to enable communication. (Step 10
8,109). When the end of communication is detected (step 110), the relay contacts 9 and 5 are opened to complete the series of operations (steps 111 and 112).

After the above-mentioned dial pulse or bush pulse is sent (steps 104 and 106), even if the response detection section 10 monitors the lines L1 and L2 for a predetermined period of time (approximately 1 minute),
If the polarity is reversed or an answer tone is not detected (affirmative result in step 113), it is assumed that there is no response, and the process proceeds to step 111 and subsequent steps, and both relay contacts 9 and 5 are opened, and the series of operations ends. do.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional device, it is difficult to deal with line disconnections such as line opening (on-hook state) of the other party's network control device and physical disconnection of the telephone line that occurs during communication. However, the phone line continues to be put on hold, and the disconnection of the line is determined only after an error occurs in the predetermined communication protocol.
It was having a negative impact on communication.

The present invention has been made in consideration of the above points, and makes it possible to check the status of the telephone line during communication and determine whether the line is disconnected, thereby eliminating the need to put the telephone line on hold unnecessarily or waste communication control time. The purpose of this invention is to provide an automatic calling network control device that prevents calls from occurring.

[Means for Solving the Problem] In order to solve the problem, the present invention includes a line disconnection detection means for detecting a line disconnection state of a telephone line that occurs during communication; A forced line opening means is provided to forcibly open the telephone line when the telephone line is opened.

[Operation] The line disconnection detecting means detects the occurrence of a line disconnection state during communication, and the forced line opening means forcibly opens the telephone line upon detection.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a circuit diagram showing an automatic calling network control device according to an embodiment of the present invention. Components similar to those in FIG. 2 are denoted by the same reference numerals, and a description thereof will be omitted.

In FIG. 1, a varistor 11 is connected in series to the dial pulse relay contact 5 near the line Ll, and a shunt resistor 12 is connected in parallel to the varistor 11. Furthermore, the light emitting diodes 16 and 17 of the photocouplers 13 and 14 are connected in parallel with each other, and a series circuit consisting of this parallel circuit and a current limiting resistor 15 is connected in parallel to the varistor 11. The anode side of the light emitting diode 16 is connected to the connection midpoint between the relay contact 5 and the varistor 11, and the cathode side of the light emitting diode 17 is connected to the connection midpoint.

Therefore, the varistor 11 lights up the light emitting diodes 16 and 17 as appropriate based on the potential difference generated between its two terminals when a call is made, when a caller's response is detected, and when communication is in progress.

Each phototransistor 1 in the photocoupler 13.14
8. Each collector of 19 has a pull-up resistor of 20
．． 21 to a voltage line of 5[vl], and each emitter is connected to a voltage line of 0[vl]. Detection signals LA and LB, which will be described later, are supplied to the control section 22 from the collectors of the phototransistors 18 and 19.

Note that the filter 23 is for extracting the busy sound frequency component from the signals from the telephone lines L1 and L2, and after the extracted busy sound Sa is amplified via the amplifier circuit 24, The waveform shaping circuit 25 shapes the pulse signal into a pulse signal, which is then given to the control section 22 as a busy tone signal detection signal sb. That is, the filter 23,
The amplifier circuit 24 and the waveform shaping circuit 25 constitute a busy tone signal detection section.

The operation of the automatic calling network control device having the above configuration will be explained below.

FIG. 4 is an operation flowchart of the device shown in FIG. 1, FIGS. 5 to 8 are timing charts of the operation in each state, and FIG. 9 is a signal waveform diagram when busy tone is detected.

Note that in FIG. 4, steps corresponding to those in FIG. 3 are denoted by the same reference numerals.

A series of controls starts when a call is made from the local side.

First, the relay contact 5 is closed by the relay operation of the dial pulse sending unit 4 (time t1 in FIG. 5(C)), and the line L
1. Put L2 into a loop state (step 101). At this time, lines L1 and L2 are -48[Vl, O[V
l,! : (Fig. 5 (A), (B)), the light emitting diode 16 lights up, the photocoupler 13 turns on (Fig. 5 (O)), and the detection signal LA becomes the logic "L" level. (Figure 5 (F)). On the other hand, since the photocoupler 14 remains in the off state, the detection signal LB is
), remains at the logic "H" level (FIG. 5(G)).

Thereafter, after waiting for a beep for connection confirmation for 3 seconds (step 102>), the control unit 22 stores the logic states of the detection signals LA and LB (step 114).

Next, steps 103 to 106 are executed in the same way as in the conventional device. When the other device captures the line, the lines L1 and L2 become 0 [Vl and -48[vl], respectively, and the polarity is reversed (FIGS. 6(A) and (B)).

As a result, the light emitting diode 16 is turned off, the photocoupler 13 is turned off (FIG. 6(C)), and the detection signal LA
becomes the logic rH level (FIG. 6(E)).

On the other hand, the light emitting diode 17 lights up and the photocoupler 14 is turned on (FIG. 6 (0)), and the previous detection signal L
After confirming that A and LB are inverted, a response is detected (affirmative result in step 107), and the inverted detection signal L
The states of A and LB are stored (step 115).

Next, the relay contact 9 is closed (step 108) and the communication state is entered. Thereafter, after a short predetermined time (approximately 3 seconds) for the line to stabilize, a line disconnection determination is performed (step 116).
~119). First, it is monitored whether the telephone line connected to the device is physically disconnected (step 117).
). When disconnected, both lines L1 and L2 are 0[
vl (time t3 in Figure 7 (^), (B)), both the light emitting diodes 16 and 17 go out and the photocouplers 13 and 14 are both in the OFF state (Figure 7 (C), (D)).
, detection signals LA and LB are both at the logic rH'' level (
Figure 7 (E), (F)). Thus, the detection signal LA,
If both LBs reach the logic rH level, it is determined in step 117 that the line is disconnected, and relay contacts 9 and 5 are opened to end the operation (steps 111 and 112).
).

If disconnection of telephone lines L1 and L2 cannot be detected, it is monitored whether the other party's device has opened the line (step 1).
18). If the other device opens the line, line L1
and L2 switch to -48[Vl and 0[Vl], respectively (time t4 in FIG. 8 (8) and (B)), the light emitting diode 16 is turned on, the light emitting diode 17 is turned off, and the photocouplers 13 and 14 are turned on, respectively. OFF state and OFF state (Fig. 8(C)).

(0)), the detection signal LA becomes the logic "L" level, and the detection signal LB becomes the logic "rH" level (Fig. 8 (E), (m). Thus, when the logic levels of the detection signals LA and LB are inverted. In step 118, it is determined that the rotation of the partner device is open, and the relay contacts 9 and 5 are opened to end the operation (steps 111 and 112).

If the polarity reversal cannot be detected in step 118, the arrival of busy tone is monitored (step 119).
. In practice, there are exchanges that do not reverse the polarity even when the other party releases the line, so such exchanges are monitored for line release by detecting a busy tone. Here, the busy tone is 400 [H2], -60 as is well known.
It is applied to the lines L1 and L2 at 0 impulses/minute and a make rate of 50%, and is taken out by the filter 23 (FIG. 9(A)). This extracted busy sound Sa is transmitted to the amplifier circuit 2.
4 and the waveform shaping circuit 25 in order to generate the pulse signal sb(
9(8)) and provided to the control section 22.

Therefore, when this pulse signal sb is applied, it is determined in step 119 that the rotation of the partner device is open, and the relay contacts 9 and 5 are opened to complete the operation (step 1
11,112).

If line disconnection cannot be detected in this step 118, check whether the communication has ended or not (step 110).
If the process has not been completed, the process returns to step 117 and continues to monitor the line disconnection state. Monitoring in this way will not detect line disconnection (when communication ends,
Relay contacts 9 and 5 are opened to end the operation (steps 111 and 112).

After sending the dial pulse or bushing pulse described above (steps 104 and 106), the response detection unit 10 monitors the lines L1 and L2, and if the polarity does not reverse even after a predetermined period of time (approximately 1 minute) has elapsed, or if the answer is If no tone is detected (affirmative result in step 113), it is assumed that there is no response and the process proceeds to steps 111 and subsequent steps;
Relay contact 9 and relay contact 5 are opened to complete the operation.

Therefore, according to the above-described embodiment, when it is detected that there is no electrical connection between the device and the telephone line or that the other party's device has opened the line during communication, the line is released as a line disconnection. It is possible to prevent telephone lines from being put on hold unnecessarily and from consuming communication control time. Accordingly, according to this embodiment, a part of the line disconnection detection configuration also serves as the response detection section (10), so the configuration can be simplified compared to adding a new function. Can be done.

Note that the configuration for monitoring the potential state of the line is not limited to the configuration of the above-described embodiment, and various configurations may be applied.

[Effects of the Invention] As described above, according to the present invention, a detecting means for detecting a line disconnection state during communication is provided, and the telephone line is forcibly opened at the time of detection, so that the line is not unnecessarily disconnected. It is possible to obtain an automatic calling network control device that can prevent calls being put on hold and communication control time being consumed.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of an automatic calling network control device according to the present invention, FIG. 2 is a circuit diagram showing a conventional device, FIG. 3 is an operation flowchart of the conventional device, and FIG. 4 is a diagram showing the above embodiment. 5 to 8 are timing charts of each part thereof, and FIG. 9 is a signal waveform diagram regarding the busy sound detection section. 11... Ballista, 13.14... Photocoupler, 2
2...Control unit, 23...Filter, 25...Waveform shaping circuit, Ll, L2...Telephone line.

Claims (1)

[Scope of Claims] An automatic calling network control device that automatically calls by specifying a destination number, comprising: line disconnection detection means for detecting a line disconnection state of a telephone line that occurs during communication; An automatic calling network control device comprising: a forced line opening means for forcibly opening the telephone line when the telephone line is opened.