JP4285007B2 - Line terminal equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a line terminal device that collects information of a data terminal device such as a home security panel or a gas shut-off device by ringing communication using a communication line.
[0002]
[Prior art]
As shown in FIG. 2, this type of line terminal device 1 is a device that collects information of a data terminal device 2 by a central monitoring device 5 via a public line 3 and an exchange 4.
[0003]
Here, the data terminal device 2 is a device with a communication function built in a microcomputer. For example, the data terminal device 2 is built in a gas meter attached to a gas consumer's house, and can read the use state of the gas by communication.
[0004]
Reference numeral 6 denotes a terminal interface unit which transmits / receives a message to / from the data terminal device 2.
[0005]
A central control unit 7 analyzes a message received by the line terminal device 1 and performs overall control.
[0006]
The telephone 8 at the gas customer's house is usually connected to the public line 3 by a telephone connection unit 9.
[0007]
The telephone connection unit 9 can be connected to or disconnected from the public line 3 by the control from the central control unit 7.
[0008]
The telephone state detection unit 10 monitors the line voltage of the public line 3, and determines that the telephone 8 is off-hook if it is several volts, and is on-hook if it is around 48V.
[0009]
Next, the ringing communication of the line terminal device 1 will be described.
[0010]
In the case of ringing communication, the number of detections of the 16HZ telephone ringing signal of the ringing call signal sent from the switching center 4 is set in advance as a condition for answering the ringing incoming call to the ringing incoming call determination unit 11 of the line terminal device 1. Keep it.
[0011]
The ringing communication is started by the transmission from the central monitoring device 7, and in the exchange 4 that receives the transmission, the telephone ringing of 16 Hz for 1 second in a cycle of 3 seconds following the polarity inversion to the line to which the line terminal device 1 is connected. A ringing call signal on which the signal is superimposed is transmitted. The telephone 8 rings in response to the 16HZ telephone ringing signal.
[0012]
Further, while a 16 Hz telephone ringing signal is generated from the exchange 4 every 3 seconds, the ringing detection unit 12 of the line terminal device 1 has a 16 Hz telephone ringing signal transmitted from the exchange 4 onto the public line 3. Output the status.
[0013]
When the ringing detection unit 12 detects a 16HZ telephone ringing signal, the ringing incoming call determination unit 11 counts up the 16HZ telephone ringing signal and determines whether the set incoming response condition has been reached.
[0014]
When the ringing call signal from the switching center 4 continues, the ringing arrival determination unit 11 reaches the set condition.
[0015]
Then, the central control unit 7 sets the network control unit 13 in a closed state (off-hook), forms a DC loop with the public line 3 and the exchange 4, and captures the line.
[0016]
When the line is acquired, the exchange 4 stops sending the ringing call signal and notifies the central monitoring device 5 that the line has been connected.
[0017]
In addition, the central control unit 7 performs central monitoring via the public line 3 and the switching center 4 from the ringing incoming call response unit 14 in order to notify the caller (in this case, the central monitoring device 5) that the line terminal device 1 has acquired the line. An incoming call response signal is transmitted to the device 5.
[0018]
The central monitoring device 5 that has confirmed the incoming call transmits a telegram in the form of a modem signal to the line terminal device 1 or the data terminal device 2 via the public line 3 and the exchange 4.
[0019]
The message in the modem signal format is demodulated by the transmission / reception unit 15 of the line terminal device 1 and received by the central control unit 7.
[0020]
When the received message is a message to the line terminal device 1 itself, the central control unit 7 creates a response message, modulates it by the transmission / reception unit 15 and responds to the central monitoring device 5 in the form of a modem signal.
[0021]
When the received message is a message to the data terminal device 2, the central control unit 7 converts the message into a format suitable for the data terminal device 2 and transmits it via the terminal interface unit 6.
[0022]
When the central control unit 7 receives the response message from the data terminal device 2 via the terminal interface unit 6, the central control unit 7 converts it into a message in a modem signal format suitable for the central monitoring device 5, modulates it by the transmission / reception unit 15, and performs central monitoring. Transmit to device 5.
[0023]
Thereafter, transmission / reception of messages is repeated between the central monitoring device 5 and the line terminal device 1 and the data terminal device 2.
[0024]
When the communication is ended, the central monitoring device 5 transmits a communication end message to the line terminal device 1.
[0025]
Upon receiving this communication end message, the central control unit 7 transmits a communication end response message to the central monitoring device 5, and then the network control unit 13 opens the DC loop (on-hook), disconnects the line, and ends the communication.
[0026]
However, in the configuration as shown in FIG. 2, when ringing communication is performed from the central monitoring device 5 when there is a resident, the resident has not reached the number of 16HZ telephone ringing signals set as the ringing incoming response condition. When the telephone 8 is off-hooked, the switching center 4 stops sending the 16HZ telephone ringing signal, so that the ringing incoming call determination unit 11 has a problem that the incoming call response condition is not satisfied and the ringing incoming call cannot be made. A line terminal device having the following structure has been devised.
[0027]
Note that components having the same numbers as those in FIG. 2 are components having the same names and functions, and the description thereof is omitted.
[0028]
16 is a public line, which is an ISDN line, and 17 is a TA with a built-in DSU. The line terminal device 18 is connected to the public line 16 via the TA17 analog port.
[0029]
An NCU selection signal detector 19 detects an analog signal of a predetermined format transmitted from the central monitoring device 5.
[0030]
An NCU response signal output unit 20 returns an incoming response signal when the signal detected by the NCU selection signal detection unit 19 is determined by the selection signal of the terminal itself and the central control unit 21.
[0031]
The NCU response signal output unit 20 has a plurality of types of response signals, and the telephone 8 connected to a signal (NCU response signal A) that responds when the connected telephone 8 does not off-hook the public line 16. Is transmitted separately from the signal (NCU response signal B) that responds when the public line 16 is off-hook.
[0032]
Reference numeral 22 denotes an NCU second selection signal detection unit, and within a predetermined time after the selection signal of the own terminal is detected by the NCU selection signal detection unit 19 (several minutes within the time in which the central monitoring device 5 can perform the corresponding process for the person at home). Wait again for the same selection signal to be transmitted.
[0033]
Reference numeral 23 denotes a line maintenance determination unit. After the NCU selection signal detection unit 19 detects the selection signal of its own terminal, the telephone 8 is put on hook within a predetermined time (the same time as the predetermined time of the NCU second selection signal detection unit 22). Is monitored by the output from the telephone state detection unit 10.
[0034]
If the NCU second selection signal detection unit 22 does not detect an analog signal in a predetermined format again or the line maintenance determination unit 23 cannot detect the on-hook state of the telephone 8 even after the predetermined time has elapsed, ringing occurs. End the incoming call determination and return to the standby state.
[0035]
The central control unit 21ha controls the entire line terminal device 18.
[0036]
Next, the operation of the line terminal device 18 will be described.
[0037]
In the ringing incoming call determination unit 11, the number of detections of a 16HZ telephone ringing signal is set as the number of incoming call responses in advance as a ringing incoming call response condition.
[0038]
The ringing communication is started by the transmission from the central monitoring device 5, and when the exchange 4 that has received the call calls the line terminal device 18, the analog port of the TA 17 makes a phone call of 16 Hz for 1 second in a cycle of 3 seconds following polarity reversal. A ringing call signal on which a ringing signal is superimposed is transmitted. The telephone 8 is ringed by the 16HZ telephone ringing signal.
[0039]
Next, while a 16 Hz telephone ringing signal is generated from the switching center 4 at a cycle of 3 seconds, the ringing detection unit 12 of the line terminal device 18 outputs the presence / absence state of the 16 Hz telephone ringing signal.
[0040]
When the ringing detection unit 12 detects a 16HZ telephone ringing signal, the ringing incoming call determination unit 11 counts up the 16HZ telephone ringing signal and determines whether or not the set incoming response condition has been reached.
[0041]
When the call from the switching center 4 continues, the TA 17 continues to send a telephone ringing signal. Here, if the telephone 8 is off-hooked by a home person before reaching the set condition in the ringing incoming call determination unit 11, the telephone 8 forms a DC loop with the TA 17 to capture the line.
[0042]
When the line is seized, the switching center 4 informs the central monitoring device 5 that the line has been seized, and also stops the calling, so the TA 17 also stops sending the telephone ringing signal.
[0043]
The central monitoring device 5 transmits an analog signal in a predetermined format via the public line 16 to the line terminal device 18 to be communicated.
[0044]
On the other hand, since the central control unit 21 detects the off-hook of the telephone 6 by the telephone state detection unit 10 during the determination by the ringing incoming call determination unit 11, the network control unit 13 is set to high impedance, and the NCU selection signal detection unit 19 The detection of this predetermined type of analog signal is monitored.
[0045]
When this analog signal is detected by the NCU selection signal detection unit 19, the central control unit 21 causes the NCU response signal output unit 20 to transmit the NCU response signal B.
[0046]
The central monitoring device 5 that has received the NCU response signal B can recognize that the line terminal device 18 is not off-hooked due to the establishment of the ringing incoming response condition, but that the connected telephone 8 is off-hooked.
[0047]
Further, when the analog signal of this predetermined format is detected by the NCU selection signal detection unit 19, the line maintenance determination unit 23 can determine that the communication is to the line terminal device 18 by transmission from the central monitoring device 5. Therefore, the telephone state detector 10 monitors whether the telephone 8 is on-hook for a predetermined time from now on.
[0048]
At this time, the resident who has off-hooked the telephone 8 will hear the analog signal transmitted from the central monitoring device 5 and may immediately go on-hook the telephone 8 after determining that it is not a normal telephone.
[0049]
In this case, the fact that the telephone 8 is on-hooked by the telephone state detection unit 10 can be detected by restoring the analog port line voltage of the TA 17 from several V to 48 V. Therefore, the line maintenance continuation unit 23 prevents the line from being disconnected. The network controller 13 immediately goes off hook within 0.1 seconds.
[0050]
Thereafter, the telephone 8 is disconnected from the public line 16 by the telephone connection unit 9 and the NCU response signal A is transmitted from the NCU response signal output unit 20 to enable communication.
[0051]
[Problems to be solved by the invention]
However, the above configuration has the following problems.
[0052]
When a line terminal device is connected to a general analog public line, it is connected to an NTT exchange via a public line. Therefore, when a DC loop is formed off-hook of the telephone 8, the telephone 8 is off-hooked. When on-hook from, the line voltage immediately recovers from several volts to 48 volts.
[0053]
Therefore, if the telephone voltage is monitored by the telephone status detection unit 10, the telephone 8 can be detected on-hook, so that the line terminal device can be closed immediately within 0.1 second so that the DC loop is not opened. It is possible to keep the line seized.
[0054]
On the other hand, when the public line on the line terminal device side is an ISDN line, the line terminal device is connected to an analog port of TA that can transmit and receive analog signals.
[0055]
Depending on the TA, when the DC loop is formed off-hook of the telephone 8, when the telephone 8 is turned off-hook, the line voltage of the analog port is restored from several volts to 48V after line disconnection processing with the public line side. There is.
[0056]
Therefore, when connected to this TA, the line terminal device detects the on-hook and closes the DC loop after the public line is disconnected.
[0057]
Therefore, when the line terminal device is closed, the line has already been disconnected, and the line cannot be captured.
[0058]
When communicating with the central monitoring device via the ISDN line in this way, there is a problem that the line terminal device cannot communicate with the central monitoring device if it is connected to the TA where the line voltage recovery of the analog port is delayed. It was.
[0059]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a telephone connection unit for connecting / disconnecting a telephone to / from a line, a network control unit for controlling impedance on the line, and a call sent from a public line. A ringing detection unit for detecting a ringing signal of a ringing ringing signal, a telephone state detection unit for detecting a telephone off-hook or on-hook, and a telephone state detection unit for detecting a telephone ringing signal while the ringing detection unit detects a telephone ringing signal. When detected, the NCU selection signal detection unit for detecting an analog signal of a predetermined format sent through the line in a state where the network control unit is set to high impedance, and the analog signal of the predetermined format is detected by the NCU. When the selection signal detection unit detects, the network control unit is immediately closed and the telephone is disconnected from the line. Those having a line control unit for controlling the talk machine connection.
[0060]
According to the above invention, when a call is made from the line side at the start of ringing communication, the ringing detection unit detects the telephone ringing signal. Thereafter, if the telephone connected to the line terminal device is off-hooked before the determination of the incoming call response condition is established by the ringing incoming call determination unit, the telephone state detection unit detects the telephone off-hook. The network control unit detects an analog signal of a predetermined format by the NCU selection signal detection unit in a high impedance state.
[0061]
If the detected signal is determined to be a selection signal of the terminal itself, the line control unit immediately closes the DC loop of the network control unit and controls the telephone connection unit to disconnect the telephone from the line.
[0062]
Therefore, it is not necessary to detect that the off-hook telephone is on-hook, and even if there is a delay in restoration of the line voltage, the line can remain captured and communication with the central monitoring device can be performed.
[0063]
DETAILED DESCRIPTION OF THE INVENTION
The line terminal apparatus according to the present invention includes a telephone connection unit for connecting / disconnecting a telephone to / from a line, a network control unit for performing impedance control on a public line, and a ringing call sent when a call is made from the line. A ringing detection unit for detecting a telephone ringing signal of a signal, a telephone state detection unit for detecting an off-hook or on-hook of the telephone, and a network when a telephone state detection unit detects an off-hook of the telephone while the ringing detection unit is detecting a telephone ringing signal. An NCU selection signal detection unit for detecting an analog signal of a predetermined format transmitted via a line in a state where the control unit is in a high impedance state, and a network when a selection signal of its own terminal is detected by the NCU selection signal detection unit A line control unit that immediately closes the control unit and controls the telephone connection unit to disconnect the telephone from the line; Those having.
[0064]
When a ringing communication is started from the line side, a ringing detection unit detects a telephone ringing signal. Thereafter, if the telephone connected to the line terminal device is off-hooked before the determination of the incoming call response condition is established by the ringing incoming call determination unit, the telephone state detection unit detects the telephone off-hook.
[0065]
The network control unit detects an analog signal of a predetermined format by the NCU selection signal detection unit in a high impedance state. If the detected signal is determined to be a selection signal of the terminal itself, the line control unit immediately closes the DC loop of the network control unit and controls the telephone connection unit to disconnect the telephone from the line.
[0066]
Therefore, it is not necessary to detect that the off-hook telephone is on-hook, and even if there is a delay in restoration of the line voltage, the line can remain captured and communication with the central monitoring device can be performed.
[0067]
Further, when the telephone is disconnected from the line by the line control unit, an NCU response signal output unit that returns an incoming call response signal to the line and becomes in a communicable state is provided.
[0068]
The line control unit closes the DC loop of the network control unit and controls the telephone connection unit to disconnect the telephone from the line, and then returns the incoming response signal from the NCU response signal output unit to the central monitoring device via the line. The central monitoring device can determine that communication with the line terminal device is possible.
[0069]
【Example】
An embodiment of the present invention will be described below with reference to FIG.
[0070]
Example 1
In FIG. 1, components having the same numbers as those in FIGS. 2 and 3 are components having the same names and functions, and the description thereof is omitted.
[0071]
A public line 30 is an ISDN line, and 31 is a TA with a built-in DSU.
[0072]
This TA 31 is a model in which the line voltage of the analog port is restored after the line disconnection process.
[0073]
The line terminal device 32 is connected to the public line 30 via the TA 31 analog port.
[0074]
A line control unit 33 controls the telephone connection unit 9 so that the network control unit 13 is immediately closed and the telephone 8 is disconnected from the public line 30 when the NCU selection signal detection unit 19 detects the selection signal of the own terminal. .
[0075]
When the telephone 8 is disconnected from the public line 30, the line control unit 33 returns an incoming response signal from the NCU response signal output unit 20 to the public line 30.
[0076]
The central control unit 21 controls the entire line terminal device 32.
[0077]
Here, it is assumed that the number of detections of the 16HZ telephone ringing signal is set as the number of incoming call responses as the ringing incoming call response condition in advance.
[0078]
The ringing communication is started by a call from the central monitoring device 5, and the exchange 4 that receives the call calls the public line 30 to which the line terminal device 32 is connected.
[0079]
Since the public line 30 is an ISDN line and the TA 31 is connected to this line, the line terminal device 32 is called from the analog port of the TA 31.
[0080]
At the time of calling, the TA31 analog port transmits a ringing calling signal in which a telephone ringing signal of 16 Hz is superposed for 1 second every 3 seconds following polarity reversal. The telephone 8 is ringed by the 16HZ telephone ringing signal.
[0081]
When this 16HZ telephone ringing signal is generated, the output of the ringing detector 12 of the line terminal device 32 outputs the presence / absence state of the 16HZ telephone ringing signal.
[0082]
When the ringing detection unit 12 detects a 16-Hz telephone ringing signal, the ringing incoming call determination unit 11 counts up the number of incoming calls and determines whether or not the set incoming response condition has been reached.
[0083]
When the call from the switching center 4 continues, the telephone ringing signal is continuously sent out from the analog port of the TA 31 at a cycle of 3 seconds.
[0084]
When the telephone 8 is off-hooked by a home person before reaching the set condition in the ringing incoming call determination unit 11, a line is captured by forming a DC loop with the TA 31.
[0085]
When the line is captured, the TA 31 stops sending the telephone ringing signal. Further, the central monitoring device 5 is informed that the line has been captured via the public line 30 and the exchange 4.
[0086]
The central monitoring device 5 transmits an analog signal of a predetermined format to the line terminal device 32 via the public line 30.
[0087]
This analog signal is modulated into a digital signal via an ISDN line, demodulated by TA 31, and output from the analog port.
[0088]
On the other hand, the central control unit 21 detects the off-hook of the telephone 8 by the telephone state detection unit 10 during the determination by the ringing incoming call determination unit 11, so that the network control unit 13 is set to high impedance and the NCU selection signal The detection unit 19 monitors whether the analog signal is detected.
[0089]
When this analog signal is detected by the NCU selection signal detection unit 19, the line control unit 33 immediately closes the network control unit 13 and then disconnects the telephone 8 from the public line 30 by the telephone connection unit 9. An NCU response signal A is transmitted from the response signal output unit 20.
[0090]
Therefore, even if the resident listens to the analog signal transmitted from the central monitoring device 5 and on-hooks the telephone 8, the network control unit 13 is in a closed state, so that the DC loop can be maintained. Even stay connected.
[0091]
The NCU response signal A is received by the central monitoring device 5 via the TA 31, the public line 30, and the exchange 4.
[0092]
Since the central monitoring device 5 can determine that the line terminal device 32 has become communicable, it communicates by transmitting a telegram in the form of a modem signal to the line terminal device 32 via the exchange 4, the public line 30, and the TA 31. To start.
[0093]
The message in the modem signal format is received by the transmission / reception unit 15 of the line terminal device 32, analyzed by the central control unit 21, and communication is performed according to the received message.
[0094]
Therefore, it is not necessary for the line terminal device 32 to monitor with the line voltage of the analog port of the TA 31 that the telephone 8 that has been off-hooked by a person at home is on-hooked.
[0095]
Accordingly, communication can be performed even if the line voltage is changed from off-hook to on-hook, even if the line voltage is not immediately restored and the TA 31 is connected.
[0096]
Further, since the NCU second selection signal detection unit necessary for the configuration of the conventional example of FIG. 3 is not required, the configuration is simple and easy to implement.
[0097]
If several types of analog signals of a predetermined format are prepared and assigned to each line terminal device, another line terminal device implemented according to the present invention is connected to the position of the telephone 8 so that the same signal can be obtained. A plurality of line terminal devices can be connected to the line.
[0098]
Therefore, it is possible to communicate with a large number of data terminal apparatuses using a single line.
[0099]
Here, the embodiment has been described in which the consumer's public line 30 is an ISDN line, but it is possible to connect the line terminal device of the embodiment of the present invention even if the consumer's public line 30 is a general analog public line. It is.
[0100]
Also, by changing the on-hook / off-hook determination level of the telephone state detection unit 10, it becomes possible to connect to an extension of a 24V PBX, etc., so that the line voltage is not immediately restored even when the telephone goes from off-hook to on-hook. The same effect can be achieved for this.
[0101]
In addition, in the case where the home phone is not off-hooked by the resident, but the model with the answering machine and the FAX is attached, even if the telephone of the telephone itself is turned off automatically, if the device of this embodiment is connected, the answering machine or There is no need to wait until the FAX enters an on-hook state after a certain period of time, and immediate communication with the central monitoring device 5 is possible and efficient communication is possible.
[0102]
【The invention's effect】
As described above, according to the line terminal device of the present invention, when a ringing call is received, before the determination of the incoming call response condition is established by the ringing incoming call determination unit, after the telephone connected to the line terminal device is off-hooked, When the NCU selection signal detection unit detects an analog signal of a predetermined format, the line control unit immediately closes the DC loop of the network control unit and controls the telephone connection unit to disconnect the telephone from the public line. Even if there is a delay in line voltage recovery due to on-hook, the line can remain captured and communication can be performed with the central monitoring device.
[Brief description of the drawings]
FIG. 1 is a block diagram of a line terminal device in an embodiment of the present invention. FIG. 2 is a block diagram of a conventional line terminal device. FIG. 3 is another block diagram of a conventional line terminal device.
2 Data terminal device 4 Switching center 5 Central monitoring device 6 Terminal interface unit 8 Telephone 9 Telephone connection unit 10 Telephone state detection unit 11 Ringing incoming call determination unit 12 Ringing detection unit 13 Network control unit 14 Ringing incoming call response unit 15 Transmission / reception unit 19 NCU selection Signal detection unit 20 NCU response signal output unit 21 Central control unit 30 Public line 31 TA
32 Line terminal device 33 Line control unit

Claims (2)

A line terminal device connected to the TA that communicates with the central monitoring device via the ISDN line and restores the line voltage of the analog port after line disconnection processing,
A telephone connection for connecting and disconnecting the telephone to the line;
A network control unit that performs impedance control on the line;
A ringing detection unit for detecting a ringing ringing signal of a ringing ringing signal sent when a call is made from a line;
A telephone state detector for detecting off-hook or on-hook of the telephone;
When the ringing detection unit detects a telephone ringing signal and the telephone state detection unit detects an off-hook of the telephone, an analog of a predetermined format that is sent via a line with the network control unit set to high impedance An NCU selection signal detection unit for detecting a signal;
Wherein immediately is閉結in advance the NCU selection signal detector analog signals determined format to detect the network control unit, and a line control unit for controlling the telephone connection unit to decouple the telephone set from the line Line terminal device provided.   2. The line terminal apparatus according to claim 1, further comprising an NCU response signal output unit that returns an incoming response signal to the line and becomes in a communicable state when the telephone is disconnected from the line by the line control unit.

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