JP2940276B2 - Line terminal 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 line terminal system in which a first terminal such as a gas meter communicates with a third terminal such as a center via a second terminal. Related to data communication means when the terminal is connected wirelessly.

[0002]

2. Description of the Related Art Cordless (wireless) telephones using relatively small antenna power have become widespread in homes. Also,
A specific low-power radio station system for telemetering and telecontrol using radio within a relatively narrow range was established in 1989.
It has been decided on a month. Therefore, it is expected that the system will be widely used not only for telephones but also for telemeters / telecontrols of household appliances such as gas meters.

A line terminal system of this kind for a telemeter using such a radio is described below. The first example is an example disclosed in Japanese Patent Publication No. 63-20071 in which a second terminal is connected to a center which is a third terminal by a no-ringing communication method using a telephone line, and a second terminal is connected. And the first terminal are wirelessly connected to perform communication between the first terminal and the third terminal. As a form of communication between the first terminal and the second terminal, the second terminal wirelessly calls the first terminal and receives a meter reading transmitted from the terminal in response to the call.

A second example is disclosed in Japanese Patent Publication No. 60-160498. When a manual switch of the first terminal is pressed, the meter is read from the first terminal to the second terminal by radio. The value is transmitted.

A third example is an example disclosed in Japanese Patent Publication No. Sho 62-179096, in which a mobile terminal, which is a second terminal, calls the first terminal by radio and responds to the first terminal.
This is to transmit the meter reading value sent from the terminal.

As described above, when the first terminal is called from the second terminal, the first terminal transmits the meter reading value in response to the call, and the communication unit transmits the meter reading value from the first terminal. Is provided.

Although a line terminal system using wireless communication has been described as a conventional example, at present, a first terminal such as a gas meter or a water meter installed in each home is connected to a second terminal by wire. Are widely used, and are designed to operate for 10 years using a lithium battery as a power supply.

[0008]

However, such a conventional technique has the following problems.

When the first terminal is called from the second terminal, the communication means for transmitting the meter reading value in response to the calling of the first terminal not only reads the meter reading value but also reads the gas when the first terminal is a gas meter. Communication means capable of remote control such as closing the shut-off valve by a signal from the third terminal, but always keeps the first terminal in a reception standby state waiting for being called by the second terminal. Must be turned on, and the power consumption of the first terminal increases compared to the current terminal. For example, in the case of specific low-power radio, the current of the receiving circuit unit consumes as much as 40 mA to 60 mA just by waiting for reception. The current gas meter has a lithium battery of 1200 mAh to 2400
mAh's are used, only 2 for wireless communication
Even if a 400 mAh battery is used, it will be consumed in about 48 hours, and it is necessary to take measures to supply power from the outside.

[0010] The means for transmitting the meter reading value from the first terminal includes:
There is a problem that the first terminal cannot be remotely controlled at any time from the third terminal.

The present invention solves such a conventional problem. A first terminal such as a gas meter and a second terminal are connected wirelessly, and a second terminal and a third terminal are connected via a public communication line. And a line terminal system in which a first terminal and a third terminal communicate with each other, and providing a communication means for remote control capable of reducing power consumption for wireless communication of the first terminal. Aim.

[0012]

In order to solve the above-mentioned problems, a line terminal system according to the present invention comprises a first terminal and a second terminal connected to each other by radio, and a second terminal connected via a public communication line. And a third terminal connected to the third terminal. The second terminal is connected to the third terminal via a public communication line, and receives a call from the first terminal.
And a message relay means for relaying a request message from the first terminal to the first terminal, the first terminal comprising: an operation means for operating information and a driving portion; a radio signal transmission means; and a radio signal transmission means at predetermined time intervals. Only when a request message is received from the second terminal via the radio signal transmission means within a predetermined time after the power is supplied to the second terminal and the second terminal is called, and the operation means is driven in accordance with the content of the request message. It consists of communication means.

[0013]

According to the present invention, the first terminal supplies power to the radio signal transmission means at predetermined time intervals of the inquiry type communication means to call the second terminal and receive a request message by the above configuration. Therefore, the wireless signal transmission means consumes power intermittently. Further, the second terminal is connected to the third terminal by the receiving means, and if there is a call from the first terminal, the third terminal is connected.
The request message from the terminal is transferred to the first terminal by the message relay means. Then, the first terminal receives the request message from the third terminal by the inquiry-type communication unit and drives the operation unit, whereby the third terminal remotely controls the first terminal.

[0014]

An embodiment of the present invention will be described below with reference to FIG.

In the line terminal system of the present invention, a first terminal 1 and a second terminal 2 which are gas meters are connected by a wireless line 15, and a second terminal 2 and a third terminal 3 serving as a center are connected to a public communication line. 16 are connected.

The first terminal 1 comprises a radio signal transmission means 5 for transmitting and receiving radio signals to and from a radio line 15, an inquiry type communication means 6, an operation means 4, and a battery 7 as a power supply. The operating means 4 includes a shutoff valve 9 for shutting off gas, an information section 8 for storing information necessary for operation as a gas meter,
The control unit 1 for controlling the shutoff valve 9 and rewriting the information unit 8
Construct from 0.

The inquiry-type communication unit 6 includes a power supply control unit 12 for stopping supply of power to the wireless signal transmission unit, and an inquiry communication control unit 11. The inquiry communication control unit 11 drives the communication power control unit 12 at predetermined time intervals to supply power to the wireless signal transmission unit 5 and call the second terminal 2. Only when the request message is received from the second terminal 2 via the wireless signal transmission means 5 within a predetermined time after the calling, the analysis is performed and the operation means 4 is driven.

The second terminal 2 includes a receiving means 13 for connecting from the third terminal 3 via a communication line 16,
It is composed of a message relay unit 14. The message relay means 14
After being connected to the third terminal 3 by the receiving means 13, when a call is made from the first terminal, the request message from the third terminal 3 is relayed to the first terminal 1.

Next, the operation of the embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In this embodiment, the first
The inquiry communication control unit 11 of the terminal 1 of the second terminal 2 sends out a call signal every three minutes (every predetermined time), so that the second terminal 2
Is called, and after the call, the standby (within a predetermined time) for receiving the request message is performed for 100 ms. Therefore,
If the request message is not received within 100 ms, the inquiry communication control unit 11 stops power supply to the wireless signal transmission unit 5. After the receiving means 13 connects to the third terminal 3, the message relay means 14 is driven, and the message relay means 14 waits for a call from the first terminal 1 for four minutes.

Next, the operation of transmitting a request message from the third terminal to the first terminal and closing the gas shut-off valve 9 of the operating means 4 will be described.

The first terminal 1 has an inquiry communication control unit 1
1 supplies power to the wireless signal transmission means 5 using the power supply control unit 12 every three minutes, and sends out call signals 17a and 17b. The power supply to the wireless signal transmission means 5 is performed only for a very short time during which the call signals 17a and 17b are transmitted every three minutes. The reason for this is that the second terminal 2 does not receive a connection request from the third terminal 3 and the operation of the message relay 14 of the second terminal 2 is stopped, so the inquiry communication control unit 11 of the first terminal 1 This is because the request message is not received within 100 ms even if the call signals 17a and 17b are sent out, so that the operation ends with a timeout. Assuming that the connection request 18 is sent from the third terminal 3 after the call signal 17b is sent from the first terminal 1 and the connection is made by the receiving means 13 of the second terminal 2, the message relay means 14 Operate. The message relay means 14 is driven by the receiving means 13 and waits for four minutes to receive the call signal. Also,
The message relay unit 14 receives the request message 19 for closing the gas shut-off valve of the first terminal 1.

If the message relay unit 14 receives the call signal 17c within four minutes, the message relay unit 14
The request message 19 received from the third terminal 3 within ms is transmitted to the first terminal. Then, the response message 20 is transmitted to the third terminal 3, and the connection with the third terminal is released. After transmitting the call signal 17c, the inquiry communication control unit 11 of the first terminal 1 is in a standby state of receiving the request message within 100 ms, similarly to the case where the call signals 17a and 17b are transmitted. Therefore, the inquiry communication control unit 1
1 receives the request message 19 transmitted by the message relay unit 14 and requests the operation unit 4 to close the shutoff valve 9.
Then, the inquiry communication control unit 11
To stop the power supply to the wireless signal transmission means.
The operation unit 4 closes the gas shutoff valve by the control unit 10. The inquiry communication control unit 11 repeats the operation of sending a call signal again every three minutes.

As another embodiment, writing of the control information of the gas meter from the third terminal 3 to the information section 8 of the first terminal can be performed by the same means as in the first embodiment.

Thus, in the line terminal system of the present invention, remote control of the first terminal is performed from the third terminal.
When the current flowing through the circuit of the wireless signal transmission means 5 in the specified low-power wireless communication is 50 mA, the following operation is performed.

For example, the time for sending the call signal is 1
Assuming that there is no remote control request at 00 ms, the first terminal 1a of the line terminal system of the present invention activates the power supply control unit 12 so that the inquiry communication control unit 11 sends out a call signal every three minutes, and the wireless communication is started. The time for supplying power to the signal transmission means 5 is 200 ms each time. Also, 24
If a lithium battery of 00 mAh is used for wireless communication, it consumes 43,200 hours, which is about five years. In the case of a gas meter, the frequency with which the shut-off valve of the gas meter is closed remotely is fair and the measures of the present invention are sufficient. In addition, technology for driving a frequency synthesizer that consumes a large amount of power for specific low power with low power is progressing rapidly, and it is considered that the margin is further increased.

In the other embodiment of the present invention, the case where the first terminal is a gas meter has been described. However, the present invention can be applied to any other terminal requiring remote control. Also, the third
Although the example in which the third terminal confirms whether the first terminal 1 has received the request message from the first terminal 3 is not shown, a response message 20 is transmitted from the inquiry communication control unit 11 of the first terminal 1. You may do so. Furthermore, although the embodiment has been described in which the call waiting signal from the first terminal 1 is waited only when the message relay means 14 is driven by the receiving means 13, the communication between the third terminal 3 and the second terminal 2 has been described. When the message relay unit 14 receives a request message from the third terminal 3 in a state where the connection is maintained, a unit that waits for a call signal from the first terminal 1 may be used.

Further, as another example, writing the control information of the gas meter from the third terminal 3 to the information section 8 of the first terminal can be performed by the same means as in the above embodiment.

[0028]

As described above, according to the line terminal system of the present invention, the first terminal can provide communication means that can be intermittently performed without continuing reception standby. The power consumption by wireless communication for control can be reduced. For example, when applied to a gas meter or the like, wireless communication can be supported by increasing the battery capacity without supplying external power.

[Brief description of the drawings]

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

FIG. 2 illustrates an operation example of the system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st terminal 2 2nd terminal 3 3rd terminal 4 Operation means 5 Wireless signal transmission means 6 Inquiry-type communication means 13 Receiving means 14 Message relay means 15 Wireless line

──────────────────────────────────────────────────の Continued on front page (72) Inventor Masaaki Sakata 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. In-house (72) Inventor Takeshi Muramatsu 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasuo Yoshimura 1006 Okadoma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56) Reference Document JP-A-63-252058 (JP, A) JP-A-5-128387 (JP, A) JP-A-5-41887 (JP, A) JP-A-4-157300 (JP, A) JP-A-2- 257794 (JP, A) JP-A-2-51799 (JP, A) JP-A-62-164362 (JP, A) JP-A-62-24113 (JP, A) JP-A-56-80954 (JP, A) (58) Fields surveyed (Int. Cl. ⁶ , (DB name) H04M 11/00-11/10 H04Q 9/00 311

Claims (1)

(57) [Claims] A first terminal and a second terminal connected to each other by radio; and a third terminal connected to the second terminal via a public communication line. The terminal is a receiving means for connecting to the third terminal via the public communication line, and a request message from the third terminal is sent to the first terminal by wireless communication when a call is made by wireless communication from the first terminal. The first terminal comprises an operation means for operating information and a driving part, a radio signal transmission means, and a power supply to the radio signal transmission means at predetermined time intervals, and the second terminal Only when the request message is received from the second terminal via the wireless signal transmission means within a predetermined time after calling the request message, the inquiry type communication means for driving the operation means in accordance with the content of the request message. Line terminal Stem.