JPH03222566A - Line terminal equipment - Google Patents

Abstract

PURPOSE:To reduce considerably power consumption of a battery and to make the size of the battery small and to reduce the capacity by supplying power supply at communication between a line terminal equipment and a data communication terminal equipment from a telephone line. CONSTITUTION:When a line terminal equipment 2 is in standby state, a battery power 23 is applied only to a control section 26. When a call request comes from a data terminal equipment 3 to the control section 26, the control section 26 closes a DC circuit switching section 21 to apply power voltage from a telephone set 1 to the line terminal equipment 2 and supplies power also to the data terminal equipment 3. The data terminal equipment 3 uses the power to make communication to a call destination via the line terminal equipment 2 and the control section 26 opens the DC circuit switching section 21 after the end of communication and restores to the standby state. Thus, since the battery in the line terminal equipment is used only for the auxiliary power supply in the standby state, the current consumption is reduced considerably and the battery is made small in size and small in the capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a line terminal device for connecting a data terminal device such as a gas meter or water meter to a telephone line.

2. Description of the Related Art In recent years, technology that uses batteries and telephone lines as a driving power source for line terminal devices that connect data terminal devices for automatic meter reading and the like to telephone lines has become mainstream.

Conventionally, this type of line terminal device has been constructed as shown in FIG. 3, and its control has been based on the means shown in FIG. 4.

In FIG. 3, the line terminal bag W2 connects the data terminal device 3 to the telephone line 1, and also has the function of supplying power to the data terminal device 3 during communication. The line terminal device 2 is always connected to a DC circuit switching section 21 that terminates the telephone line 1, a voltage conversion section 22 that converts the voltage of the DC circuit switching section 21 into a driving voltage for the line terminal device 2, and a control section. A battery 23, a switching section 24 that switches the power supply of the line terminal device 2, and a data terminal interface section 25 that supplies power from the line terminal device 2 to the data terminal device 3 and serves as an interface with the data terminal device 3. , a control section 26 that controls the DC circuit opening/closing section 21 and the switching section 24 that switches the power supply voltage, and detects a transmission request from the data terminal device 3.

Next, the control means in the above configuration will be explained with reference to FIG. 4. When the data terminal device 3 is not communicating, the line terminal device W2 is in a standby state as shown in FIG.
3 has been added. When the data terminal 3 sends an outgoing request to the control unit 26 (FIG. 4, 32), the control unit 26 connects the switching unit 24 to the battery 23 side, applies power to the entire line terminal device 2, and simultaneously applies power to the data terminal device 3. (Fig. 4, 33).

This power supply performs data communication such as a destination telephone number between the data terminal device 3 and the control unit 26 (FIG. 4, 34).

Next, the control unit 26 closes the DC circuit opening/closing unit 21 and connects the destination of the data terminal device and the line terminal device (fourth
35), after the DC circuit opening/closing section 21 is brought into the closed state, the control section 26 switches the connection destination of the switching section 24 to the voltage conversion section 22. That is, power is supplied to the line terminal device 2 from the telephone line 1 (FIG. 4, 36), after which the data terminal device 3 communicates with the destination via the line terminal device 2. After the communication ends, the control section 26 opens the DC circuit opening/closing section 21 and returns to the standby state. At this time, battery power is supplied only to the control section 26 of the line terminal device 2.

From the viewpoint of power supply, when the line terminal device 2 and the data terminal device W3 are communicating, the battery 23 supplies power, and when the data terminal device 3 is communicating with the destination, the telephone Line 1 is used as a power supply source.

Problems to be Solved by the Invention With such conventional methods, there is a limit to miniaturization of battery capacity. This is because, while the power consumption in a normal standby state is minute, the power consumption during communication between the line terminal device 2 and the data terminal device 3 is relatively very large, and the power consumption of the battery 23 is Device 2 and data terminal device 3
This is because it was already decided.

The present invention solves the above-mentioned problems, and aims to provide a method for reducing the size and cost of a battery installed in a line terminal device.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a DC circuit switching unit that supplies power from a telephone line, and a voltage conversion unit that converts the voltage from the DC circuit switching unit into a driving voltage for a line terminal device. Department and
It consists of a data terminal interface that supplies power from the line terminal device to the data terminal device and serves as an interface with the data terminal device, and a control section that controls the DC circuit switching section and detects transmission requests from the data terminal device. There is.

Effect of the Invention With the above-described configuration, the present invention fixes the t'B supply source during communication between the line terminal device and the data terminal device to the telephone line, which conventionally accounts for most of the power consumption of the battery, so the power consumption of the battery is reduced. can be significantly reduced, and costs can be reduced by making the battery smaller and lowering its capacity.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, a line terminal device 2 has the function of connecting a data terminal device 3 to the telephone line 1 and supplying power to the data terminal device 3 during communication, as in the conventional example.

The line terminal device 2 includes a DC circuit opening/closing unit 21 that connects the telephone line vA1 and simultaneously controls the power on and off except for the control unit.
, a voltage conversion unit 22 that converts the voltage of the DC circuit switching unit 21 into a driving voltage of the line terminal device 2, and a voltage conversion unit 22 that supplies power from the line terminal device 2 to the data terminal device 3 and serves as an interface with the line terminal device 2. The data terminal interface section 25 is composed of a control section 26 that controls the DC circuit opening/closing section 21 and detects a transmission request from a data terminal device.

The control procedure in the above configuration will be explained with reference to FIG. 2. When the line terminal device 2 is in a standby state, the battery power supply 23 is applied only to the control unit 26 in the line terminal device 2 (FIG. 2, 41), and from the data terminal 3 to the control unit 2.
6 (FIG. 2, 42), the control unit 26
By closing the DC circuit opening/closing section 21, a power supply voltage is applied from the telephone line 1 to the line terminal device 2, and power is also supplied to the data terminal device 3 (Fig. 2, 43). 3 and the control unit 26 in the line terminal device 2 (the second
44), that is, the telephone line is used as a supply source of 1lart for communication between the line terminal device 2 and the data terminal device 3, which were conventionally driven by batteries.

Thereafter, similarly to the conventional example, the data terminal device 3 communicates with the destination via the line terminal device 2 (FIG. 2, 45), and after the communication ends, the control unit 26 opens the DC circuit opening/closing unit 21 and enters the standby state. Return to At this time, battery power is supplied only to the control section 26 of the line terminal bag M2.

From the viewpoint of power supply, since the auxiliary battery 23 in the line terminal device 2 is used only as a bank-up power source during standby, its current consumption is extremely small, ranging from 10 μA to 3 μA.
It is about 0 μA, which is extremely small compared to the several mA required during communication between the line terminal device and the data terminal device.

As described above, according to the line terminal device according to the embodiment of the present invention, since power is supplied from the telephone line during communication between the line terminal device and the data communication terminal, the power consumption of the battery is significantly reduced. This makes it possible to reduce the size and capacity of batteries.

Although only one data terminal device is connected in this embodiment, a plurality of data terminal devices may be connected.

Effects of the Invention As is clear from the above embodiments, according to the present invention, the power for data communication between the line terminal device and the data terminal device is supplied from the telephone line. Furthermore, since the battery inside the line terminal device is only used as an auxiliary power source during standby, its current consumption can be kept extremely low, making it possible to reduce the size and capacity of the battery. can.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a line terminal device according to an embodiment of the present invention, FIG. 2 is a flowchart of the same line terminal device, FIG. 3 is a block diagram of a conventional line terminal device, and FIG. 4 is a conventional line terminal device. 3 is a flowchart of the device. 1...Telephone line, 2...Line terminal device, 3...Data terminal device, 21...DC circuit switching unit, 22...・Voltage converter, 23...
. . . Battery, 25 . . . Data terminal interface section, 26 . . . Control section.

Claims (1)

[Claims] A DC circuit switching section that terminates a telephone line and controls the output voltage depending on the termination state; a voltage conversion section that converts the output voltage from the DC circuit switching section into a driving voltage; and a data terminal device and a connection to the DC circuit switching section. a data terminal interface unit that functions as a communication data interface and supplies power supplied from the voltage conversion unit to the data terminal device; The DC circuit opening/closing section is closed and voltage is applied to the voltage converting section to supply power from the data terminal interface section to the data terminal device, and when there is no transmission request from the data terminal device, the DC circuit is opened/closed. A line terminal device consisting of a control section that controls to open the section.