JP2838321B2 - Data communication system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication system and, more particularly, to various terminal devices connected to the extension of a private branch exchange provided in a company or building, and a center provided outside the company or building. The present invention relates to a data communication system for performing bidirectional data transmission between a communication side and a public network.

[0002]

2. Description of the Related Art Conventionally, a telemeter system has been provided as a system for performing automatic meter reading of a plurality of vending machines whose centers are located at remote locations and gas meters provided in each consumer's home. When adopting the telemeter system, a new dedicated telephone line should be drawn as a line for data transmission, or the system should be constructed in a form that uses a public telephone line that has already been drawn into the consumer's premises. I was In this telemeter system, NTT
(NIPPON TELEGRAPH ANDDELE
No ringing service provided by PHONE CORPORATION is used, and the center side arbitrarily collects desired data. The use of the no-ringing service is a very effective means because the center can collect data without ringing the bell of the telephone in the user's house when performing automatic meter reading of a vending machine or a gas meter.

FIG. 5 is a schematic configuration diagram of a communication system using a telephone including a conventional private branch exchange.

In FIG. 5, the communication system includes a management center for executing data collection and data processing in the system, and a user connected to the management center via, for example, a public network 13 provided by NTT. . The management center includes a center system 12 that includes a computer and has a function of directly controlling communication with the public network 13. On the other hand, the user side has a private branch exchange (hereinafter abbreviated as PBX) 15 for controlling communication of an extension to which terminal devices 16 to 18 having a call function are connected and controlling communication between the extension and a public network 13 which is an external line. including.

In the communication system including the PBX 15 configured as described above, when a call request from the center system 12 arrives at the PBX 15 via the public network 13, the PBX 15 responds accordingly. It operates to select a desired terminal device based on the content and establish a line between the selected terminal device and the center system 12. When the line is established as described above, the center system 12 and each of the terminal devices 16 to 18 can communicate bidirectionally via the exchange function of the PBX 15.

[0006]

However, if an attempt is made to construct the above-described telemeter system for a company or a building, the PBX 15 as shown in FIG. Therefore, each of the terminal devices 16 to 18 connected to the extension of the PBX 15 cannot be called by a ringing gig directly from the external management center side.

In other words, conventionally, when a terminal device is directly connected to a public network without providing a PBX, bidirectional data communication is performed using a no ringing service, and the center side performs automatic meter reading. Was completed. However, it is difficult to implement the no-ringing service for the extension of the PBX 15 shown in FIG. 5 because there are significant restrictions on the change of the line voltage and the timing of the signal. In order to overcome this restriction, P
There was also a problem that the specification of the BX15 had to be fundamentally changed and the cost was too high.

In FIG. 5, the center system 12
If the user wants to establish a line with each of the terminal devices 16 to 18 via the public network 13 and the PBX 15 to perform data communication, the larger the amount of transmitted / received data, the longer the communication time, the more the center system 12 and the PBX 1
5, the line is held for a long time, and there is a problem that a call request in another terminal device is more likely to be put in a waiting state, which causes a decrease in communication efficiency.

[0009] Therefore, an object of the present invention is to provide a data exchange between a center system connected to a private branch exchange via a public network and a plurality of data terminal devices connected to the private branch exchange via an extension line. An object of the present invention is to provide a data communication system capable of keeping the line use cost of the entire system low without changing the specifications of the exchange and without providing a separate line, and preventing a decrease in communication efficiency.

[0010]

A data communication system according to the present invention includes a user system including at least one or more data terminal devices, a private branch exchange for connecting each data terminal device via an extension, and a private branch exchange. A data communication system including a center system connected to the exchange via a public line and transferring data to and from each data terminal device, wherein the user system connects an extension and a dial-in line to the private branch exchange. And a communication terminal connected to the center side system via a dial-in line and a public network. The communication terminal unit responds to an incoming call from the center side system, and Communication connection means for communication-connecting the data with the center system; receiving data transmitted from each data terminal device; Data transfer means for transferring data between the terminal device and the center side system, and when receiving data transmitted from each data terminal device, analyze the contents of the received data and temporarily store the received data, A determination means for immediately determining whether to transfer the data to the center side system using the data transfer means.

[0011]

The data communication system according to the present invention is constructed as described above, wherein the communication terminal is connected to a dial-in line connected between the communication terminal and the private branch exchange and between the private branch exchange and the center system. Since it is connected to the center system via a public network connected between them, a general subscriber telephone can be used as a dial-in line.
The communication terminal device does not frequently transmit to the center side system, and the probability of holding the dial-in line between the center side system and the private branch exchange for a long time can be reduced,
A decrease in communication efficiency can be prevented.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a configuration of a data communication system employing a private branch exchange according to a first embodiment of the present invention.

In FIG. 1, this data communication system constitutes one type of telemeter system. Specifically, the system includes a management center side and a user side connected to the management center side via a public network 13. The management center includes a center system 12 having a function of collecting data transmitted from a user and executing data processing by executing a predetermined program on the collected data. The user side is a private branch exchange (hereinafter, referred to as a private branch exchange).
PBX). The PBX 15 has extension 2
3 is connected to the sub-center 21 and the extension 2
Terminal devices 16 to 18 are connected via 5 to 27, respectively. The PBX 15 is a terminal device 16 to 1
8 and the public network 13, that is, a communication connection between an outside line and an extension line, and a sub center 21 and the terminal device 1.
Line control is also performed by using extensions 6 to 18. Each of the terminal devices 16 to 18 is a terminal device having a function of transmitting information, such as a copying machine, a vending machine, an electric meter, a gas meter, or a water meter. The sub-center 21 has a function of transmitting and receiving data to and from the terminal devices 16 to 18 via the PBX 15 and has an external line 22 provided independently of an external line connected to the PBX 15, although its internal configuration will be described later. It also has a function of controlling communication with the public network 13 via the Internet. Therefore, the data in the terminal devices 16 to 18 is once collected in the sub-center 21 via the PBX 15 via each of the extensions 25 to 27 and further via the extension 23, and thereafter, via the external line 22 under the control of the sub-center 21. Processing can be performed so as to be transmitted to the public network 13.

FIG. 2 is a schematic diagram showing the configuration of the sub-center 21 according to one embodiment of the present invention.

In FIG. 2, the sub-center 21 includes a CPU 21a for controlling and managing the center 21 itself, a memory 21b for accessing data stored therein by the CPU 21a, a communication modem 21c, and an input / output control unit 21d. . The communication modem 21c is a PB
An extension 23 connected to X15 and an outside line 22 connected to the public network 13 are connected, and operate so as to control connection and disconnection of these communication lines. The input / output control unit 21d includes the CPU 21a and the sub center 21.
It operates to interface with an input / output device group 30 (keyboard, display, audio output device, etc.) connected to the outside of the device.

The CPU 21a stores data provided from a communication modem 21c connected to the preceding stage in a memory 21b.
And reads data stored in the memory 21b in response to a signal given from the communication modem 21c, and sends the read data to a line via the communication modem 21c. I do.

As shown in FIG. 1, the sub-center 21 is connected to the public network 13 and the terminal 1 independently of the PBX 15.
It operates to establish a communication line with 6 to 18. Therefore, when a large amount of data excluding a call is transmitted and received between the terminal devices 16 to 18 and the center system 12, the large amount of data is transmitted through the sub-center 21 and the external line 22 is dedicated. , PBX15
The communication load of the PB does not increase and the PB
The load on the line between X15 and the public network 13 does not increase.

In the system shown in FIG. 1, the case where a line is connected from the external center system 12 to the terminal devices 16 to 18 connected to the extension of the PBX 15 will be described.

First, the sub center 21 is called directly from the external center system 12, and a line is established between the center system 12 and the sub center 21 via the public network 13. After this line connection, the terminal number of the terminal device for which data collection is desired is transmitted from the external center system 12 to the sub-center 21. The terminal number is a number previously assigned to each of the terminal devices 16 to 18 registered in the system, and the terminal device can be uniquely specified by the terminal number. Upon receiving the terminal number from the center system 12, the sub center 21 sets the extension with the corresponding terminal number to P
Connect via BX15. In this manner, the terminal devices 16 to 18 connected to the extension of the external center system 12 and the PBX 15 through the sub-center 21
It is possible to perform data communication directly with the device.

Next, a description will be given of a case where a line is connected from each of the terminal devices 16 to 18 to the external center system 12 in the system shown in FIG.

First, each of the terminal devices 16 to 18 calls the sub-center 21 by calling the terminal and establishes an extension connection. Thereafter, the terminal device transmits predetermined data to the sub-center 21. In response to the reception of the transmission data, the sub-center 21 analyzes the content of the reception data, and determines whether to temporarily store the reception data or immediately transmit the reception data to the external center system 12. That is, the CPU 21a of the sub center 21 analyzes data received from the terminal device via the communication modem 21c according to a predetermined program process, stores the received data in the memory 21b in response to the analysis result, After a lapse of time, the sub-center 21 makes a call and performs processing to transmit the stored data to the external center system 12. Further, the CPU 21a of the sub-center 21 immediately determines the emergency state of the terminal device based on the analysis result of the data received from the terminal device, and immediately transmits the received data to the outside line 2 in response to the determination.
2 and the transmission to the center system 12 via the public network 13.

As described above, in the system shown in FIG. 1, bidirectional data communication between the center system 12 via the subcenter 21 and each of the terminal devices 16 to 18 connected to the extension of the PBX 15 is possible. It is.

In the system shown in FIG. 1, since all the terminal devices 16 to 18 are connected to the extension of the PBX 15, there is an advantage that simplicity of construction, easiness of maintenance and reduction of operation cost can be achieved. is there. Further, although the line 22 of the sub-center 21 is directly connected to the public network 13, it can be connected to an extension dial-in line of the PBX 15.

FIG. 3 is a schematic diagram showing the configuration of a data communication system employing a private branch exchange according to a second embodiment of the present invention.

The data communication system shown in FIG. 3 and the data communication system shown in FIG. 1 are compared.
The communication line with the center system 12 is directly connected to the public network 1
3 is connected to the center system 12 of the sub-center 21 shown in FIG.
It is connected to the X15 extension dial-in line 22a. That is, in FIG. 1, the emergency information generated in any of the terminal devices 16 to 18 is transmitted to the external line 22 between the sub-center 21 and the center system 12.
Since the transmission is performed via the external line, there is an advantage that a delay in transmission of the emergency information due to the outside line busy can be avoided. Further, in the system shown in FIG. 3, since a general subscriber telephone line is used for the dial-in line 22a, there is an advantage that the line use cost of the entire system can be reduced.

In the data communication system shown in FIG. 3, a case will be described in which the terminal devices 16 to 18 are called from the center system 12 to make a line connection to perform meter reading or download data to the terminal device.

The center system 12 is connected to the sub-center 21 via the public network 13 and the dial-in line 22a.
Is called, the center system 12 and the sub center 21
Establish a line connection between Thereafter, the center system 12 transmits the telephone number (corresponding to the terminal number) assigned to the terminal device with which communication is desired. The sub-center 21 can call the corresponding terminal device connected to the extension via the PBX 15 by dialing the received telephone number. As a result, a line is established between the subcenter 21 and the terminal device via the dial-in line 22a, and data can be transmitted between the center system 12 and the terminal device via the subcenter 21.

As shown in FIG. 3, when a plurality of extensions 23 and 24 are connected to the sub-center 21, a plurality of terminal devices can be simultaneously called to transmit and receive data to and from the center system 12. As a result, the line connection time between the center system 12 and the sub-center 21 can be reduced.

Next, in the system shown in FIG. 3, data communication in the case where some abnormality occurs in the terminal devices 16 to 18 will be described.

When an abnormal state occurs in the terminal devices 16 to 18, the terminal devices 16 to 18 first call the sub-center 21 via the extension and the PBX 15 and establish an extension with the sub-center 21. Data transmission of information on the abnormality that has occurred.

The sub-center 21 receives the transmission data and temporarily stores it in the memory 21b. CP
The U21a analyzes the data stored in the memory 21b, and immediately determines that an emergency is required, establishes a line connection with the center system 12 via the dial-in line 22a and the public network 13 via the communication modem 21c. Then, the abnormality information is read out from the memory 21b and transmitted to the line. The center system 12, which has received the abnormal data transmitted from the sub-center 21, further analyzes the received data and, if it is determined that the current abnormal state is extremely urgent, requests the user to respond accordingly. I do. That is, the center system 12 communicates with the input / output control unit 2 of the sub-center 21 via the established public network 13.
Processing is performed to ring the bell 31 connected to 1d.
The user can confirm the occurrence of an abnormal emergency condition by ringing the bell 31 and take prompt action, so that, for example,
It is possible to avoid a very emergency situation such as occurrence of water leak and gas leak.

In the system shown in FIG. 3, for example, instead of connecting the terminal device 16 directly to the extension 25,
The connection may be made to the extension 25 via the adapter 32. The adapter 32 connects the extension 25 to one side, connects the telephone 33 and the terminal device 16 to the other side, and controls connection switching so that the extension 25 is connected to one of the telephone 33 and the terminal device 16. The protocol in the communication control using the adapter 32 is MSS
A system known as (multi-service switcher) is used.

When called from the sub-center 21 via the PBX 15, the adapter 32 first detects an incoming call. After that, the sub-center 21 is
A signal is transmitted to connect the communication line with the terminal 2 to either the telephone 33 or the terminal device 16. When the connection with the terminal device 16 is established, the sub center 21
Transmits a signal for calling a predetermined terminal device 16 following the calling of the adapter 32. Upon receiving the predetermined signal from the sub-center 21, the adapter 32 controls to connect the extension 25 and the terminal device 16 accordingly.

When the adapter 32 is called to call the telephone 33 from another telephone or the like, when the adapter 32 detects that the predetermined signal has not been received even after a predetermined time has elapsed after the detection of the incoming call, the adapter 32 responds. Ext. 25
Is switched to be connected to the telephone 33 side. As a result, the telephone 33 can be connected to the public network 13 to make a normal voice call.

As described above, by providing the adapter 32, a plurality of data terminal devices, that is, the telephone 33 and the terminal device 16 can be connected to the external public network 1 via one extension 25.
3 can be connected.

FIG. 4 is a schematic diagram showing a configuration of a data communication system employing a private branch exchange according to a third embodiment of the present invention.

In FIG. 4, the data communication system includes the management center side and the user side as described above, and the center system 12 on the management center side connects to the sub center 21 on the user side via the public network 13 to the dial-in line 22a. And connected to the PBX 15 via an external line. In this system, the terminal devices 16 to 1
Information on abnormal conditions that occurred in each of the 8
External center system 12 directly via PBX 15
Can be transmitted to

[0039]

According to the present invention, in response to an incoming call from the center side system, communication connection means for communicatively connecting each data terminal apparatus and the center side system, and transmitting data from each data terminal apparatus. By providing a communication terminal device having a data transfer means for receiving and transferring data between the data terminal device and the center side system in response to the communication terminal device, it is possible to connect to the extension of the private branch exchange, which has been difficult in the past There is an effect that automatic two-way data communication becomes possible between the various data terminal devices and the center system connected to the public network.

The above effect is achieved by using one line provided by the public network as the dedicated line for data communication. Further, since an expensive line such as a conventional ringing circuit is not used, the cost is extremely low. There is also an effect that the system can be configured.

For data communication, a communication terminal device is provided, and the center system connected to the public network and various data terminal devices connected to the extension of the private branch exchange are connected via the communication terminal device. So that
This data communication system can be newly introduced without having to set a dial-in line for each data terminal device and without changing the extension system by the existing private branch exchange at all. Moreover, the communication terminal device
Since it is connected to the center system through a public network connected between the private branch exchange and the center system, it is commonly used as a dial-in line. No additional telephone line is required. further,
The communication terminal device does not immediately transmit the received data to the center system.The communication terminal device analyzes the content of the received data and transmits the data. Therefore, the communication terminal device frequently transmits low urgency data to the center system. And the probability that the dial-in line is maintained for a long time between the center system and the private branch exchange can be reduced. As a result, it is possible to reduce the line use cost of the entire system and prevent a decrease in communication efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a data communication system employing a private branch exchange according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating a configuration of a sub-center according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a configuration of a data communication system employing a private branch exchange according to a second embodiment of the present invention.

FIG. 4 is a schematic diagram showing a configuration of a data communication system employing a private branch exchange according to a third embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a communication system using a telephone including a conventional private branch exchange.

[Explanation of symbols]

 12 center system 13 public network 15 PBX (private branch exchange) 16, 17 and 18 terminal device 21 sub-center 22 outside line 22a dial-in line 23, 24, 25, 26 and 27 extension 21a CPU 21b memory 21c communication modem 32 adapter 33 telephone In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A user-side system including at least one or more data terminal devices, a private branch exchange that connects each of the data terminal devices via an extension, and a user side system connected to the private branch exchange via a public network, A data communication system including a center system that transfers data to and from each data terminal device, wherein the user system is connected to the private branch exchange via an extension and a dial-in line, A communication terminal device connected to the center system via the dial-in line and the public network, wherein the communication terminal device responds to an incoming call from the center system, the data terminal device and the center Communication connection means for communicatively connecting the side systems, receiving data transmitted from each data terminal device,
Data transfer means for transferring data between each of the data terminal devices and the center-side system accordingly, when receiving data transmitted from each of the data terminals, analyzing the contents of the received data, Determining means for temporarily storing the received data or immediately transferring the received data to the center-side system using the data transfer means.