JP2002118683A - Terminal network controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To utilize an existing terminal network controller after changing an analog circuit to an ISDN circuit. SOLUTION: An analog terminal network controller 1 is provided with a meter interface 8a for communication with a meter 7a connected through a connecting terminal 6a, a communication interface 9 for communication with a digital terminal network controller 22 through the connecting terminal 6a, and a switching portion for selecting to occupy either of interfaces. When an analog circuit is changed to an ISDN circuit 20, the digital terminal network controller 22 is connected to the connecting terminal 6a which has been connected with the meter 7a, and the interfaces are changed so that the communication interface 9 and the connecting terminal 6a are connected with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal network control device in a data communication system for performing data transmission with a center device using a communication line.

[0002]

2. Description of the Related Art Conventionally, in a data communication system in which a terminal network control device is connected to an analog telephone line to perform data transmission, when changing to communication using a digital line such as an ISDN network or a radio communication network, The terminal network controller for analog cannot be used. Therefore, the terminal network controller for digital was replaced, and all the terminal devices such as meters connected to the original terminal network controller were reconnected to the new terminal network controller for digital, and the previously used analog network controller was used. Of the terminal network control devices were discarded.

FIG. 5 shows a communication system using the digital terminal network control device after the change to the ISDN network. The digital terminal network control device 40 and the center-side device 41 including a host computer and the like are connected via an ISDN line network via a center-side exchange 42 and a terminal-side exchange 43.
The digital terminal network controller 40 is connected to the terminal exchange 43 via a DSU 44, and a TA (terminal adapter) 45 is also connected to the DSU 44 as necessary.
Terminal devices such as a meter 47 and contact devices are connected to a connection terminal 46 of the digital terminal network control device 40 connected via the DSU 44. With such a configuration, communication can be performed between the center-side device 41 and the digital terminal network control device 40 in a predetermined procedure.

[0004]

When switching to the ISDN network, at least the same number of new digital terminal network controllers are provided in accordance with the number of meters connected to the original analog terminal network controller. A connection terminal is required. The connection terminals are provided on the screw terminal block, and the connection terminals are usually provided in a required number or more. Such a screw terminal block requires a large space, and the component cost is generally higher than that of the electronic component. For this reason, the cost of the new terminal network controller increases, the burden on the user increases, and the spread of the digital terminal network controller delays.

[0005] Further, since all meters connected up to that time have to be reconnected to the new digital terminal network control device, the more meters to be connected, the more time is required. In addition, when the new digital terminal network controller is installed in a location different from the previously used analog terminal network controller, the cable length from the meter to the connection terminal of the new digital terminal network controller is changed. Must be re-wired. Therefore, the work involved in the change becomes very troublesome.

[0006] In view of the above, an object of the present invention is to provide a terminal network control device capable of easily responding to a change in a communication line without imposing a large burden on a user or an operator.

[0007]

The object of the present invention is to provide a terminal network control device with a terminal interface for communicating with a terminal device connected via a connection terminal, and other terminals via the connection terminal. A communication interface for performing communication with the terminal network control device, and a switching unit that switches to use one of the interfaces is provided,
For example, when a communication line is changed from an analog line to an ISDN line and another terminal network control device compatible with the connection is connected to the connection terminal, the communication interface is switched to the connection terminal.

Thus, the second terminal network controller is connected to the connection terminal of the first terminal network controller, and the second terminal network controller is connected to the data terminal connected to the center device via the communication line. A communication system is established. Data from a terminal device connected to the first terminal network control device is sent to the second terminal network control device through the communication interface, and is transmitted from the terminal network control device to the center device via a communication line, Data transmission can be performed with the center device via the second terminal network control device.

Therefore, a new terminal network control device is required, but the terminal network control device that cannot support the changed communication line can be used without discarding it. Therefore, it is not necessary to rewire the terminal devices connected thereto, and the work involved in the change can be reduced. In addition, the newly installed terminal network controller does not need to connect a plurality of terminal devices, so the number of connection terminals can be reduced, so the space for the terminal block can be reduced, and the terminal network controller can be reduced in size and cost. I can do it.

[0010] The switching operation of the switching unit is performed so as to connect the communication interface to the connection terminal by an input signal from an external device such as a center device or a setting device. Alternatively, a detection unit for detecting that the communication line has been changed may be provided, and when the change is detected, the switching operation of the switching unit may be executed. This detection unit detects the connection state of the telephone line connection terminal. If the telephone line is connected to the telephone line connection terminal, the communication line has not been changed and the telephone line has not been connected. When it is detected, it is determined that the line has been changed. Therefore, when the line is changed, it can be detected and automatically switched, so that a setting error or the like can be prevented.
If this is reported to the center device, the center device can be made aware that the line has been changed.

[0011]

FIG. 1 shows a terminal network control apparatus according to a first embodiment of the present invention. The terminal network control device 1 is for analog use. An analog telephone line 3 is connected to a telephone line connection terminal 2, and the telephone line connection terminal 2 is connected to a control unit 5 via a telephone line interface 4. Also,
A plurality of connection terminals 6a, 6b, 6c are provided, and the meters 7a, 7b, 7c are respectively connected. Each connection terminal 6
a, 6b, and 6c are connected to the control unit 5 via the corresponding meter interfaces 8a, 8b, and 8c. In addition, these connection terminals 6a, 6b, 6c are 1
Are installed side by side on one terminal block.

[0012] Then, the meter 7 is called up by a ringing or terminal transmission from the center device by no ringing.
The meter readings from a, 7b, 7c are sent to the control unit 5 having a communication function by the meter interfaces 8a, 8b, 8c, and this data is transmitted to the center device through the analog telephone line 3.

There are two types of meters: LP gas meters and city gas meters. The former can transmit and receive 5-bit signals, and the latter can transmit and receive 8-bit signals. The specifications of the meter interface are different so that each signal can be transmitted and received according to the type of the meter. In addition, a water meter or an electric meter other than the gas meter may be connected to the connection terminal, and further, a contact device such as a switch or a sensor may be connected. The terminal interface is properly used according to such different types of terminal devices, and data transmission can be performed.

The terminal network control device 1 has a communication interface 9 equivalent to the meter 7a so that it can be used even if the communication line is changed from an analog line to a digital line.
Is provided, and one connection terminal 6 of the plurality of connection terminals is provided.
a is connectable. Communication interface 9
Is configured to be able to transmit and receive signals of the same type as the meter 7a connected to the connection terminal 6a. A switching unit is provided for switching the connection terminal 6a to connect either the meter interface 8a or the communication interface 9. The switching unit includes a latching relay 10 and a relay driving unit 11 that performs a switching operation of the latching relay 10. The relay driving unit 11 is connected to the control unit 5, and is operated by an output signal from the control unit 5.

At first, when the terminal network control device 1 is connected to the analog telephone line 3 and used, the meter interface 8a is set and the meter 7a is connected to the connection terminal 6a. Further, different types of meters 7b and 7c are connected to the other connection terminals 6a and 6c, respectively. Communication with the center device is performed via the telephone line interface 8a, and the meter readings of the meters 7a, 7b, 7c are transmitted to the center device.

Here, when the communication line of the user is changed from an analog line to an ISDN line, the terminal network control device 1 used so far cannot support a digital line. Must be installed. Therefore, as shown in FIG.
A new digital terminal network controller 22 is connected to the S / T point of the DSU 21 connected to “0”. A TA 23 and the like are also connected as necessary, and a telephone and a facsimile are connected to this.

The connection terminal 24 of the digital terminal network controller 22 is connected to the meter 7a connected to the original connection terminal 6a of the analog terminal network controller 1.
The connection terminal 25 of the digital terminal network control device 22 and the connection terminal 6a of the original analog terminal network control device 1 are connected by a cable. Nothing is connected to the telephone line connection terminal 2 of the analog terminal network control device 1.

The digital terminal network controller 22 used here has a basic structure similar to that of the analog terminal network controller 1.
Same as above, but instead of an analog circuit such as a reversal detection circuit, a rectifier circuit, and a PB transmission / reception circuit, a D-channel communication unit, an impedance matching circuit, etc. are built in for performing communication using the ISDN line 20 I have.

As described above, the existing analog terminal network controller 1 is communicably connected to the center-side device through the ISDN line 20 via the newly established digital terminal network controller 22. The external device is set in a state where it can communicate with the center device. That is, the control unit 5 that has received the input signal from the setting device or the center-side device drives the relay driving unit 11 to close the latching relay 10 from the contact on the meter interface 8a to the contact on the communication interface 9 side. Switch.

Thus, the digital terminal network control device 2
2 can access each of the meters 7b and 7c which have been connected before through the analog terminal network control device 1, so that data transmission is performed between the meters 7b and 7c and the center-side device.

Therefore, when a user's communication line is changed from an analog telephone line to an ISDN line, if the existing terminal network controller is used, the number of connection terminals of the newly installed digital terminal network controller is two. And the number of connection terminals can be reduced. Therefore, the size of the terminal block can be reduced, the size of the digital terminal network control device itself can be reduced, and the cost can be reduced. Moreover,
There is almost no need to change the meter wiring, and the work time and man-hours involved in the change can be reduced.

Further, terminal equipment such as a meter may be connected to not only the analog terminal network controller but also a digital terminal network controller. Therefore, the connection terminal of the analog terminal network control device can be used as an extension terminal for connecting a terminal device other than the terminal device, and the data communication system can transmit not only data but also other information. It can be utilized as a communication system that performs communication.

Next, a terminal network control device according to a second embodiment is shown in FIG. This is an analog terminal network control device 1, which is provided with a line detection unit 30 for detecting the connection state of the telephone line connection terminal 2, and is connected to the control unit 5. Other configurations are the same as those of the first embodiment.

The line detecting section 30 detects whether or not the analog telephone line 3 is connected to the telephone line connection terminal 2 and outputs the detection result to the control section 5. The control unit 5 controls the switching operation of the switching unit based on the detection result.
That is, if the telephone line 3 is connected, the relay driving unit 11 is controlled to switch to the meter interface 8a side and to the communication interface 9 side if the telephone line 3 is not connected.

The control contents of the terminal network control device 1 at this time will be described with reference to the flowchart shown in FIG. First,
The line voltage of the telephone line connection terminal 2 is detected by the line detection unit 30 (step S1). Next, it is checked whether the presence or absence of the line voltage has changed (step S2), and if it has changed, it is determined whether the state has continued for three minutes (step S3). Thereafter, it is determined whether there is a line voltage (step S4).

If there is a line voltage, the telephone line 3 is connected to the telephone line connection terminal 2. At this time, the line is switched to the meter interface 8a (step S5). If there is no line voltage, it is determined that the line is connected to another terminal network control device 22, and the line is switched to the communication interface 9 (step S6). .

Therefore, when the communication line is changed and the communication line is connected to a new terminal network control device, the interface is automatically switched. Therefore, there is no need to switch by a command from an external device, and no setting error occurs.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention. Although an example in which a telephone line is used as a communication line is shown, a wireless line network, a dedicated line network, or a change to an optical fiber network may be used. The switching unit may be a switch that is manually operated, and switches when performing a line change operation.

[0029]

As is apparent from the above description, according to the present invention, when a communication line is changed, an existing terminal network control device is used instead of a connection terminal, and a terminal is connected via another terminal network control device. Data transmission can be performed between the device and the center device. Therefore, the unnecessary terminal network control device can be used without discarding it. As a result, there is little need to change the wiring of the terminal equipment,
The work involved in the change can be greatly simplified. Also, when the existing terminal network controller is connected to another terminal network controller,
Since the terminal functions as a connection terminal, another terminal device can be connected, and the added value of the data communication system can be increased.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of a main part of a data communication system.

FIG. 3 is a block diagram of a terminal network control device according to a second embodiment;

FIG. 4 is a flowchart illustrating a control procedure of interface switching;

FIG. 5 is a configuration diagram of a conventional data communication system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Analog terminal network control device 2 Telephone line connection terminal 3 Analog line 5 Control unit 6a Connection terminal 7a Meter 8a Meter interface 9 Communication interface 10 Latching relay 11 Relay drive unit 20 ISDN line 22 Digital terminal network control device

Claims (6)

[Claims] A connection terminal for connecting a terminal device;
A terminal interface for communicating with the terminal device;
What is claimed is: 1. A terminal network control device comprising: a center-side device connected via a communication line; and a control unit for controlling communication with said terminal device, wherein said communication device communicates with another terminal network control device via said connection terminal. A communication interface for performing, and a switching unit that connects the connection terminal so as to be able to communicate with either the communication interface or the terminal interface is provided, and when the connection terminal is connected to the communication interface, The terminal network control device, wherein the control unit communicates with the center device via another terminal network control device. 2. A communication system comprising: a plurality of connection terminals for connecting a terminal device; a terminal interface for communicating with the terminal device; a communication interface for communicating with another terminal network control device; A control unit that controls communication between the center-side device and the terminal device connected via the control unit, and a switching unit that switches between the communication interface and the terminal interface is connected to one connection terminal, The remaining connection terminals are used as extension terminals, and when the communication interface is connected to the one connection terminal, the control unit communicates with the center device via another terminal network control device. Terminal network controller. 3. The terminal network control device according to claim 1, wherein the switching unit performs a switching operation so as to connect the connection terminal to the communication interface according to an input signal from an external device. 4. A telephone line connection terminal for connecting a telephone line, a connection terminal for connecting a terminal device, a terminal interface for communicating with the terminal device, and another terminal via the connection terminal. A communication interface for performing communication with the network control device, a switching unit that connects the connection terminal so as to be able to communicate with either the communication interface or the terminal interface, and a connection state of the telephone line connection terminal. A line detection unit for detecting,
A control unit that controls a switching operation of the switching unit based on an output signal from the line detection unit, wherein the control unit disconnects the communication interface when a telephone line is not connected to the telephone line connection terminal. A terminal network control device, wherein the terminal network control device is switched to connect to the connection terminal, and communicates with the center device via another terminal network control device via the connection terminal. 5. When the telephone line is connected to the telephone line connection terminal, the control unit switches the terminal interface to be connected to the connection terminal, and communicates between the terminal device and the center-side device via the connection terminal. 5. The terminal network control device according to claim 4, wherein: 6. A data communication system for performing data transmission between a center-side device and a terminal network control device via a communication line, wherein the first terminal network connectable to an analog line as the terminal network control device. A control device and a second terminal network control device connectable to a digital line are used, wherein the first terminal network control device includes a terminal interface for communicating with a terminal device and a second terminal network control device. A communication interface for performing communication, and a switching unit that switches one of the interfaces so as to be able to communicate with the connection terminal according to the type of the line, wherein the connection terminal includes a digital line when a digital line is used. A data communication system to which a second terminal network control device is connected and said terminal device is connected when an analog line is used.