JPH04137963A - Line terminal equipment - Google Patents

Abstract

PURPOSE:To reduce the current consumption of a battery by detecting a voltage drop of a telephone line and discriminating it that the line terminal equipment is not connected to the telephone line when a telephone set is not in hook-off state so as to stop power supply to a data transmission section, a DTE interface section and an incoming call detection section. CONSTITUTION:When an output of a voltage detection section 5 indicates a state of 40V or below, a line connection discrimination section 6 discriminates it whether the telephone line is not connected or the voltage is simply dropped because the telephone set is in use based on an input signal from an off-hook detection section 4. When the line connection discrimination section 6 inputs it to a central control section 10 that the line terminal equipment is not connected to the telephone line, the central control section 10 outputs a signal to a power supply control section 8 to stop power supply to all blocks such as a data transmission section 7, an incoming call detection section 11 and a DTE interface section 9. Thus, undesired consumption of the battery power supply is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a line terminal device connected to a telephone line.
In particular, the present invention relates to a line terminal device in which it is operationally effective to determine whether or not it is connected to a telephone line.

BACKGROUND OF THE INVENTION In recent years, the types of line terminal devices connected to telephone lines have been increasing, and battery-powered line terminal devices and the like have been developed for specific purposes. Here, for the purpose of automatic meter reading of gas meters and water meters, we will explain a line terminal device that is powered by battery power.

Conventionally, this type of line terminal device did not have a line connection determination function and generally had a configuration as shown in FIG. The configuration will be explained below with reference to FIG. 2.

As shown in FIG. 2, the line terminal device includes a telephone line connection terminal 1 for connecting a telephone line, a diode bridge 3 for rectifying the polarity of the telephone line, and a data transmission section for transmitting communication signals from the guide bridge 3. 7, a telephone connection terminal 2 for connecting a telephone, etc., an off-hook detection section 4 connected between the telephone line connection terminal 1 and the telephone connection terminal 2 to detect off-hook of the telephone, and controlling the battery power supply by an external input signal. a DTP interface unit 9 that is an interface between the line terminal device and DTP; an incoming call detection unit 11 that detects incoming signals from the telephone line; It is comprised of a central control section 10 that transmits data between interface sections 9 and receives signals from off-hook detection section 4 and incoming call detection section 11 as input signals.

Next, the operation in the above configuration will be explained.

First, the operation in a standby state in which the line terminal device is not communicating will be explained, and then the case where the line terminal device is communicating will be explained. DT when the line terminal equipment is in standby state
The system is currently detecting outgoing calls from E and incoming calls from the telephone line. In other words, in the power supply system, battery power is supplied to the DTE interface section 9 in order to detect a transmission request from the DTP. Battery power is also supplied to the incoming call detection section 11 to detect incoming calls from the telephone line to the line terminal device. Furthermore, the central control unit 10 updates the clock so that the line terminal device itself can make a call.

To summarize the power supplies in the above standby state, the DTE interface section 9, the incoming call detection section 11, and the central control section 1
0 is in a state where battery power is constantly supplied.

Next, the power supply when the line terminal device is in communication will be explained. When a signal is input to the central control unit IO due to a call request from the DTE interface unit 9 or an incoming call from the incoming call detection unit 11, the central control unit 10 outputs a signal to the power supply control unit 8 to perform data communication. Battery power is supplied to the transmission section 7. At the same time, battery power is supplied to the off-hook detection section 4. The above control secures a communication route for data transmission, and at the same time, when the handset is taken off-hook to use the telephone connected to the telephone connection terminal 2, the off-hook detection unit 4 is activated to realize preferential use of the telephone. It is in a detectable state.

Problems to be Solved by the Invention However, with this conventional configuration of line terminal equipment, the line terminal equipment is not connected to the telephone line, that is, the line terminal equipment is collected after being shipped from the factory or for maintenance. The DTE interface section 9 and the incoming call detection section 1 are used to detect outgoing calls from the DTE and incoming calls from the telephone line.
1 was supplied with battery power. Furthermore, at a predetermined time in the line terminal device, the power supply control section 8 was controlled to perform the outgoing operation, and power was also applied to the data transmission section 7 to perform the outgoing operation, resulting in a pointless increase in battery power. Ta.

The present invention is intended to solve the above-mentioned problems, and its first purpose is to make it possible to determine whether a line terminal device is connected to a telephone line, and its second purpose is to reduce pointless consumption of battery power. The purpose is

! ! Means for Solving the Problems In order to achieve the above object, the line terminal device of the present invention has a telephone line connection terminal for connecting a telephone line, a telephone connection terminal for connecting a telephone set, and rectifying the polarity of the telephone line. an off-hook detection section that is connected between the telephone line connection terminal and the telephone connection terminal and outputs a signal when it detects that the telephone is off-hook; A voltage detection unit that outputs a signal when the voltage falls below a predetermined value, and a line connection determination unit that uses the output signals of the off-hook detection unit and the voltage detection unit as input signals to determine whether the line terminal device is connected to the telephone set. , a data transmission section that transmits data between the diode bridge and the central control section, a power supply control section that controls the battery power supply using external input signals, and a DTE.
A DTE interface section that serves as an interface with the telephone line, an incoming call detection section that detects an incoming signal from the telephone line and outputs a signal when detected, and a power supply control section that uses signals from the line connection determination section and the incoming call detection section as input signals. It is composed of a central control section that performs data transmission between the data transmission section and the DTE interface section.

According to the above-described structure, the line connection determination section determines whether the voltage drop is caused by the use of the telephone connected to the telephone connection terminal, based on the output of the off-hook detection section, when the voltage detection section detects a voltage drop on the telephone line. Therefore, it can be determined whether the line terminal device is connected to the telephone line. The central control unit determines whether or not the line terminal device is connected to the telephone line based on the input signal from the line connection determination unit, and when the line terminal device is not connected to the telephone line, controls the power supply control unit and outputs data. Stops power supply to the transmission section, DTE interface section, and incoming call detection section. Further, since the transmitting operation is stopped even when the clock in the central control unit reaches a predetermined time, the power source is used only when necessary, and the current consumption of the battery can be reduced.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIG.

As shown in Figure 1, the line terminal device includes a telephone line connection terminal 1 for connecting a telephone line, a telephone connection terminal 2 for connecting a telephone, a diode bridge 3 for rectifying the polarity of the telephone line, and a telephone line terminal 1 for connecting a telephone line. An off-hook detection section 4 is connected between the line connection terminal 1 and the telephone connection terminal 2 and outputs a signal when off-hook of the telephone is detected, and an off-hook detection section 4 is connected to the output end of the diode bridge 3 and is connected to the voltage value of the telephone line to a predetermined value. A voltage detection unit 5 outputs a signal when the voltage is below, and a line connection that uses the output signals of the off-hook detection unit 4 and voltage detection unit 5 as input signals to determine whether the line terminal device is connected to the telephone line. The determination unit 6, the data transmission unit 7 that performs data transmission between the diode bridge 3 and the central control unit 10, and the data transmission unit 7 and D
A power supply control section 8 supplies battery power to the TE interface section 9 and the incoming call detection section 11, a DTE interface section 9 acts as an interface with the DTE, and an incoming call section detects an incoming signal from the telephone line and outputs a signal when detected. A central control unit 10 receives signals from the line connection determination unit 6 and the incoming call detection unit 11 as input signals, and controls the power supply control unit 8 and transmits data between the data transmission unit 7 and the DTP interface unit 9. It consists of

The operation in the above configuration will be explained. First, we will explain the determination operation of the line connection determination unit 6, then we will explain the standby state and the communicating state when the line terminal device is connected to the telephone line, and finally we will explain the state in which the line terminal device is connected to the telephone line. We will explain the operation when not in use.

The voltage value of the telephone line shows a voltage value of 48V when it is not in use, that is, when the telephone line is not terminated for communication.Here, the voltage detection unit 5 secures a margin and sets the voltage value of the telephone line to 40V. time is set as the threshold. When the voltage value is 40V or more, it indicates that an unused telephone line is connected, and when the voltage value is less than 40V, one of the following two cases occurs. The first case is when no voltage is applied, that is, the telephone line is not connected,
In the second case, the voltage is applied but it is less than 40V, that is, the telephone is off-hook (the telephone is in use).
If it shows 0V or more, it is determined that the line terminal device is connected to the telephone line regardless of the input signal from the off-hook detection section. Also, the output of the voltage detection section 5 is 40V.
If the following is indicated, the line connection determination unit 6 determines whether the telephone line is not connected or whether the voltage value has simply decreased because the telephone is in use, based on the input signal from the off-hook detection unit 4. will judge. In other words, if the output of the voltage detection section shows less than 40V and the output of the off-hook detection section 4 shows that the telephone is in use (off-hook detection in progress), it means that the telephone line is connected but the voltage has dropped. If the output of the voltage detection section is less than 40V and the output of the off-hook detection section 4 indicates that the telephone is not in use, the line terminal device is not connected to the telephone line. It is determined that

Next, the operation when the line terminal device is connected to the telephone line and is in a standby state and the operation during communication will be explained.0 The line terminal device is connected to the telephone line from the line connection determination unit 6 to the central control unit 10. When this is input, the central control unit 10
outputs a signal to the power supply control section 8, applies battery power to both the incoming call detection section 11 and the DTE interface section 9, and shifts to a state in which it can respond to incoming call requests from the telephone line and outgoing requests from the DTE. No voltage is applied to the data transmission section 7 which is not operating at this time. Next, when an outgoing call request or an incoming call request is input from the incoming call detection unit 11 or the DTE interface unit 9 to the central control unit 10, the central control unit l
O outputs a signal to the power supply control section 8 and sends a signal to the data transmission section 7.
Apply power to the device to enable data communication. At the end of the communication, it returns to the standby state and performs the control of the above-mentioned standby state.

Finally, we will explain the operation when the line terminal device is not connected to the telephone line. From the line connection determination unit 6 to the central control unit 1
1, when it is input that the line terminal device is not connected to the telephone line, the central control section 10 outputs a signal to the power supply control section 8, and the data transmission section 7, the incoming call detection section 11, and the DTE
The power supply to all blocks of the interface section 9 is stopped. Therefore, if the telephone line is not connected, a call request from the DTE will not be accepted. Also, battery power is applied to both the time stamp section 11 and the DTE interface section 9, which are preset in the line terminal device, and the line terminal device enters a state in which it can respond to an incoming call request from the telephone line and an outgoing request from the DTE. No voltage is applied to the data transmission section 7 which is not operating at this time. Next, when an origination request or an incoming call request is inputted to the central control unit 10 from the incoming call detection unit 11 or the DTE interface unit 9, the central control unit 10 outputs a signal to the power supply control unit 8 to turn off the power to the data transmission unit 7. is applied to enable data communication. At the end of communication, the device returns to the standby mode and performs the above-mentioned standby mode control.

Finally, from the 0-line connection determination unit 6 to the central control unit 1, which explains the operation when the line terminal device is not connected to the telephone line.
1 that the line terminal device is not connected to the telephone line, the central control 10 outputs a signal to the power supply control section 8 and all of the data transmission section 7, incoming call detection section 11, and DTE interface section 9 Stop the power supply to the block. Therefore, if the telephone line is not connected, a call request from the DTE will not be accepted. Further, since it is possible to control the transmission operation so as not to start the transmission operation even at a preset time within the line terminal device, it is possible to prevent unnecessary application of power to the data transmission section 7.

As described above, according to the line terminal device according to the embodiment of the present invention, it is possible to determine whether or not the line terminal device is connected to the telephone line using the voltage detection section 5, the off-hook detection section 4, and the line connection determination section 6. can. Furthermore, since the central control unit 10 controls the power supply control unit 8 and supplies power only to the blocks that require power supply, it is not necessary to install it after factory shipment or remove the line terminal device during maintenance. It is possible to prevent power supply, and it is possible to realize lower power consumption of the battery power source.

Although the present invention has been described with reference to an example in which low power consumption of a battery power source is realized by utilizing whether or not a line terminal device is connected to a telephone line, the method of use is not limited to this example. When detecting disconnection, resetting the system when installing a line terminal device for the first time, or detecting disconnection of the telephone line during communication, check the telephone connection terminal side or DT.
It is also possible to send an alarm signal to the E side or display it on the line terminal device.

Effects of the Invention As is clear from the above description, according to the present invention, it is possible to determine whether or not a line terminal device is connected to a telephone line using a voltage detection section, an off-hook detection section, and a line connection determination section. Furthermore, since the central control section controls the power supply control section, unnecessary consumption of battery power can be suppressed when the line terminal device is not connected to the telephone line.

The line connection determination function can also be used as a telephone line disconnection detection function and as a trigger for system reset, etc. when a line terminal device is connected to a telephone line for the first time.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a line terminal device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional example. 1...Telephone line connection terminal, 2...Telephone connection terminal, 3...Diode bridge, 4...
...off-hook detection section, 5 ... voltage detection section, 6 ... line connection determination section, 7 ... data transmission section, 8 .... Power control unit, 9...
- DTE interface unit, 10...Central side external, 11...Incoming call detection unit.

Claims (1)

[Claims] A voltage detection unit connected to a telephone line detects the voltage value of the telephone line and outputs a signal when the line voltage falls below a predetermined value, and a telephone connection terminal that connects the telephone line and the telephone. an off-hook detection unit that outputs a signal when off-hook of the telephone terminal is detected, and output signals of the voltage detection unit and the off-hook detection unit as input signals to determine whether or not a line terminal device is connected to the telephone line. A line terminal device comprising a line connection determination unit that makes a determination.