JPH10322466A - Channel terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a telephone set of a subscriber to communicate with a data terminal without ringing the telephone set through transmission from a center side by opening a DC loop of a closing circuit when caller telephone number information is coincident with a telephone number stored in advance. SOLUTION: A caller telephone number reception section 21 of the channel terminal equipment 15 receives a dial information signal, a caller telephone number comparison section 23 compares a caller telephone number analyzed by a text analysis section 22 with a telephone number that is stored in a telephone number storage section 19 and to which a central monitor 5 is connected, and when they are coincident, a call signal detection section 17 is set to a detection enable state, a closing circuit 16 is controlled simultaneously to open a DC loop and the end of reception is informed to an exchange 4. When a line terminal equipment 15 detects the call signal, the terminal equipment 15 closes the DC loop and the exchange 4 confirms it to restore the polarity of the line terminal equipment 15 and informs it to the central monitor 5 that the connection is normally made. Then the exchange is set 'through' and the communication is made between the line terminal equipment 15 and the center monitor 5 by a modem signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line terminal device for collecting data of a data terminal device such as a gas meter or a water meter from a central monitoring device such as a gas company or a water company using a public line network. It is.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional line terminal device 1 has a data terminal device 2 connected to a public line 3 and an exchange 4.
And a device for performing communication via the central monitoring device 5. Here, it is assumed that the transmitting side and the receiving side are in the same exchange station.

The data terminal device 2 is an automatic gas shut-off device (commonly known as a microcomputer meter) with a built-in communication function, which is widely used in recent years. The data terminal device 2 is connected to a gas meter to measure a gas flow rate. This is a device that shuts off and further communicates the meter reading value, the reason for the shutoff, and the like to the central monitoring device 5 via the line terminal device 1.

[0004] In order to communicate with the data terminal device 2 of this type, communication is performed using the no-ringing service of NTT, so that data collection can be performed without ringing the bell of the telephone 6 of the customer. It was possible to do.

The operation of the line terminal device 1 will be described with reference to FIG. 6. When a connection request is made from the central monitoring device 5 in accordance with the no-ringing incoming call, first, the exchange 4 gently sends the line terminal device 1 side. Polarity inversion (slow polarity inversion) is performed.

When the gentle polarity reversal is detected by the gentle polarity reversal detecting unit 8, the line terminal device 1 controls the first half-closing circuit 9 to half-close the DC loop and waits for reception of the NRS signal. This NRS signal is received by the DTMF receiving unit 10 because the DTMF signal is used in the no-ringing service for a plurality of calls.

[0007] If the received NRS signal is applicable, NRS
After the signal is interrupted, the second half-closing circuit 12 is controlled to make the DC loop half-closed with a lower impedance, and a response signal (# of DTMF) is transmitted from the DTMF transmitter 13. When the exchange 4 receives the response signal from the line terminal device 1, it informs the central monitoring device 5 (originating) that the connection has been normally established.

Thereafter, the exchange 4 becomes through and communication with the central monitoring device 5 is performed directly with the line terminal device 1 via a modem transmission / reception circuit 14 using a modem signal.

When transmitting a meter reading request message from the central monitoring device 5 to the data terminal device 2, the modem transmitting / receiving circuit 14 of the line terminal device 15 receives a modem signal from the central monitoring device 5 requesting meter reading.

In the line terminal device 1, the activation message is converted to a data terminal signal and transmitted to the data terminal device 2 via the data terminal interface 11.

When the data terminal device 2 receives this signal, it sends back a meter reading response message. In the data terminal interface 11, the return signal is converted into a modem signal by the modem transmitting / receiving circuit 14 and transferred to the central monitoring device 5.

[0012]

However, in the above-described configuration, the operator having the central monitoring device 5 needs a no-ringing service contract with NTT, which is expensive in addition to the communication cost according to the communication time. Since small service fees were required as fixed costs, the maintenance costs were large for small businesses.

[0013] Further, since no ringing service cannot be used in the terminal facility where the PBX is installed,
Since data collection is limited to the terminal calling method, there is a problem that meter reading and remote control cannot be performed at any time.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a switch for opening and closing a DC loop for a switch to match an electrical condition for communication-connecting a data terminal device to a central monitoring device. Connection circuit, a call signal detecting unit for detecting a signal for calling a telephone at a customer home, a polarity inversion detecting unit for detecting polarity inversion from the exchange, a telephone number storage unit for storing a telephone number specified in advance, and a polarity inversion. A primary control unit that closes the DC loop of the closing circuit when the detection unit detects the polarity reversal, a transmission telephone number reception unit that converts the transmission telephone number information signal from the exchange into a telegram, and a reception that is received by the transmission telephone number reception unit A message analyzer that analyzes the message, and a detectable call signal detector when the outgoing telephone number information analyzed by the message analyzer matches the telephone number stored in advance in the phone number storage. And a secondary control unit for controlling the closing circuit to close the DC loop by controlling the closing circuit when the calling signal detecting unit detects the calling signal. .

According to the above invention, when the line terminal device of the present invention is connected to the line of the customer who has subscribed to the calling telephone number display service, the data terminal can be transmitted from the center without ringing the customer's telephone. The ability to communicate with the device eliminates the expense of paying for the no-ringing service. Further, since there is no need to perform the no-ringing communication, the line terminal device does not need the DTMF receiving circuit and the semi-closed circuit required for the no-ringing communication, so that a simple configuration can be achieved.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A line terminal device according to the present invention comprises a closed circuit for opening and closing a DC loop for a switch to match an electrical condition with a switch for communication-connecting a data terminal device to a central monitoring device; A call signal detector for detecting a signal for calling a telephone at a customer's home, a polarity inversion detector for detecting a polarity inversion from an exchange, a telephone number storage for storing a telephone number specified in advance, and a polarity inversion detector for polarity A primary control unit that closes the DC loop of the closed circuit upon detecting inversion;
An outgoing telephone number receiving unit that converts the outgoing telephone number information signal from the exchange to a telegram, a telegram analyzing unit that analyzes the received telegram received by the outgoing telephone number receiving unit, and a telephony number that is analyzed by the telegram analyzing unit. When the call signal detection unit detects a call signal, the call signal detection unit controls the call signal detection unit to a detectable state when it matches the telephone number stored in advance in the number storage unit and opens the DC loop of the closed circuit, and the call signal detection unit detects the call signal. And a secondary control unit that controls the closing circuit to close the DC loop. Then, the operator having the central monitoring device does not need to use the no-ringing service of NTT, and the circuit necessary for the no-ringing communication can be deleted from the line terminal device. By connecting the line terminal device of the present invention to a terminal facility where a PBX where no ringing service cannot be used is installed, meter reading and remote control can be performed at any time. Further, the telephone connection unit for disconnecting or connecting the telephone from the public line and the outgoing telephone number obtained from the outgoing telephone number information signal from the exchange are compared with the telephone numbers stored in the telephone number storage unit, and if they match, the telephone connection unit is determined. And a telephone disconnection control unit for controlling disconnection of the telephone connected to the telephone line from the line. In the communication using the calling telephone number display service, the line terminal device completes the reception of the information signal and opens the DC loop and disconnects the telephone at the same time. Therefore, the line terminal device is connected to the line terminal device by a call signal transmission operation from the next exchange. Can prevent the phone from ringing and ringing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 is a block diagram of a line terminal apparatus according to the present invention. The components having the same numbers as those in FIG. 5 are components having the same functions. In the figure, reference numeral 15 denotes a line terminal device of the present invention. Reference numeral 16 denotes a closed circuit which opens and closes a DC loop with respect to the exchange 4 to match electric conditions, 17 denotes a call signal detection unit which detects a signal for calling the telephone 6 at the customer's home, and 18 denotes a call signal from the exchange 4. This is a polarity inversion detection unit that detects polarity inversion.

Reference numeral 19 denotes a telephone number storage unit for storing a telephone number specified in advance. 20 is a polarity reversal detection unit 1
Reference numeral 8 denotes a primary control unit which closes the DC loop of the closing circuit 16 when the polarity reversal is detected. Reference numeral 21 denotes a transmission for converting a transmission telephone number information signal transmitted from the exchange 4 to a transmission number display service contractor into a telegram. It is a telephone number receiving unit.

A message analyzing unit 22 analyzes the received message received by the sending telephone number receiving unit 21, and a sending telephone number comparing unit 23 stores a telephone number of the message analyzed by the message analyzing unit 22 as a telephone number. If the telephone number matches the telephone number stored in the unit 19 in advance, the call signal detecting unit 17 is controlled to a detectable state, and the DC loop of the closing circuit 16 is opened.

When the calling signal detecting section 17 detects the calling signal, the secondary control section 24 controls the closing circuit 16 to close the DC loop.

FIG. 2 shows a line connection sequence of the line terminal device 15 in the embodiment of the present invention. The connection operation of the line terminal device 15 connected to the public line 3 of the customer who subscribes to the calling telephone number display service will be described with reference to FIG.

Here, the telephone number of the transmission line to which the central monitoring device 5 is connected is stored in the transmission telephone number storage section 19 of the line terminal device 15 in advance.

First, the central monitoring device 5 is connected to the line terminal device 15.
Sends a connection signal by transmitting and transmitting a selection signal of the connected customer telephone number. In the exchange 4, if the destination is a customer who has subscribed to the calling telephone number display service, the connection operation is performed as follows.

First, the exchange 4 inverts the polarity with respect to the terminating terminal side and starts up. When the line terminal device 15 detects the inversion of the polarity, the primary control unit 20 as a primary response signal
To close the DC loop of the closing circuit 16 and notify the exchange 4.

Next, the exchange 4 converts information such as the calling telephone number into a modem signal and transmits it. In the line terminal device 15, the transmission information signal is received by the transmission telephone number reception unit 21, and the transmission telephone number analyzed by the message analysis unit 22 is connected to the central monitoring device 5 stored in the telephone number storage unit 19. The telephone number is compared with the outgoing telephone number comparing section 23, and when they match, the call signal detecting section 17 is set in a detectable state, and at the same time, the closing circuit 16 is opened to open the DC loop and notify the exchange 4 of the completion of reception.

After confirming the completion of reception by opening the DC loop, the exchange 4 sends a calling signal and waits for a secondary response signal. In the line terminal device 15, when a call signal is detected by the call signal detecting unit 17, the secondary control unit 24 controls the closing circuit 16 as a secondary response signal to close the DC loop. The exchange 4 confirms this and restores the polarity to the line terminal device 15 side, and notifies the central monitoring device 5 side that the connection has been normally established.
Thereafter, the exchange 4 becomes through, a communication path is established between the line terminal device 15 and the central monitoring device 5, and communication by a modem signal is performed.

When a meter reading request message is transmitted from the central monitoring device 5 to the data terminal device 2 by a modem signal, the transmission telephone number receiving section 21 of the line terminal device 15 receives the modem signal and sends a meter reading request to the data terminal device 2. When the message analysis unit 22 analyzes the message as a message, the activation message is converted into a signal and transmitted to the data terminal device 2 via the data terminal interface. Upon receiving this signal, the data terminal device 2 performs return transmission according to the content of the received message.
The return signal received by the data terminal interface 11 is converted into a modem signal by the modem transmission / reception circuit 14 and transferred to the central monitoring device 5 for communication.

According to this configuration, the operator having the central monitoring device 5 does not need to use the no-ringing service of NTT, and the line terminal device 15 does not need a circuit required for the no-ringing communication.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 3 is different from the first embodiment in that a telephone connection unit 25 for disconnecting or connecting the telephone 6 from the public line 3 and a transmission telephone number and a telephone number storage unit obtained from a transmission telephone number information signal from the exchange 4. 19
Is provided with a telephone disconnection control unit 26 for performing control of disconnecting the telephone 6 connected to the telephone connection unit 25 from the line when the telephone number is compared with the telephone number stored in.

FIG. 4 shows a line connection sequence of the line terminal device 27 according to the second embodiment of the present invention.

After detecting the polarity reversal from the exchange 4, the primary control unit 20 closes and closes the DC loop as a primary response, and the first until the information such as the calling telephone number is transmitted from the exchange 4 by the modem signal. This is the same operation as the embodiment.

Thereafter, when the outgoing telephone number receiving section 21 receives the outgoing telephone number information signal,
The message is analyzed by the message analysis unit 22 and the telephone number storage unit 19 is analyzed.
When the telephone number matches the telephone number, the DC loop is opened, and at the same time, the telephone connection unit 26 is controlled and the telephone 6 is disconnected. Therefore, after the telephone 6 is disconnected from the public line 4, a call signal is transmitted from the exchange 4.

Therefore, according to the above configuration, in communication using the calling telephone number display service, the line terminal device 2
At 7, the telephone is disconnected at the same time that the information signal has been received and the DC loop is released, so that the telephone 6 connected to the line terminal device 27 can be prevented from ringing or ringing due to the next call signal transmission operation from the exchange 4.

Further, by connecting the line terminal device 27 of the present invention to a terminal facility where a PBX where no ringing service cannot be used is installed, meter reading and remote control can be performed at any time without ringing the telephone 6.

[0035]

As described above, according to the line terminal device of the present invention, the following effects can be obtained.

(1) According to the first aspect of the present invention, by utilizing the calling telephone number display service, it is possible to communicate with the data terminal device without ringing the customer's telephone by calling from the center side, so that the no ringing service is used. There is no need to pay.

Since there is no need to perform no-ringing communication, the line terminal device has the D required for no-ringing communication.
Since a TMF receiving circuit and a semi-closed circuit are not required, the configuration is simple.

(2) According to the second aspect, since the telephone is disconnected before the calling signal of the telephone arrives after receiving the calling telephone number information signal, the central monitoring device and the data terminal device do not ring. Can communicate between

Therefore, by connecting the line terminal device of the present invention to a terminal facility where a PBX where no ringing service cannot be used is installed, meter reading and remote control can be performed at any time without ringing the telephone.

[Brief description of the drawings]

FIG. 1 is a block diagram of a line terminal device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a line connection sequence of the device.

FIG. 3 is a block diagram of a line terminal device according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a line connection sequence of the device.

FIG. 5 is a block diagram of a conventional line terminal device.

FIG. 6 is a diagram showing a line connection sequence of the device.

[Explanation of symbols]

 11 Data Terminal Interface 14 Modem Transmission / Reception Circuit 16 Closing Circuit 17 Call Signal Detection Unit 18 Polarity Reversal Detection Unit 19 Phone Number Storage Unit 20 Primary Control Unit 21 Calling Phone Number Receiving Unit 22 Message Analysis Unit 23 Calling Phone Number Comparing Unit 24 Secondary Control unit

Claims (2)

[Claims] 1. A closed circuit for opening and closing a DC loop for an exchange to match an electrical condition to communicatively connect a data terminal device to a central monitoring device, and a signal for calling a telephone at a customer home is detected. A call signal detection unit, a polarity inversion detection unit for detecting polarity inversion from the exchange, a telephone number storage unit for storing a telephone number specified in advance, and the closed circuit when the polarity inversion detection unit detects polarity inversion. A primary control unit for closing a DC loop, a transmitting telephone number receiving unit for converting a transmitting telephone number information signal from an exchange into a telegram, a telegram analyzing unit for analyzing a received telegram received by the transmitting telephone number receiving unit, and the telegram. When the outgoing telephone number information analyzed by the analysis unit matches the telephone number stored in advance in the telephone number storage unit, the call signal detection unit is controlled to be in a detectable state,
A line terminal device comprising: a calling telephone number comparing unit that opens a DC loop of the closed circuit; and a secondary control unit that closes the DC loop by controlling the closed circuit when the call signal detecting unit detects a call signal. 2. An outgoing telephone number obtained from an outgoing telephone number information signal from a telephone connection unit for disconnecting or connecting a telephone from a public line and a telephone number stored in a telephone number storage unit. 2. The line terminal device according to claim 1, further comprising a telephone disconnection control unit for controlling disconnection of a telephone connected to the telephone connection unit from a line.