JP3538536B2 - Terminal system for data communication - 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 terminal system for performing data communication with a center system using a line.

[0002]

2. Description of the Related Art Conventionally, a data communication terminal system having a terminal network controller (hereinafter simply referred to as "terminal device") for performing data communication with a center system via a line has been widely used. I have. FIG. 4 is a diagram showing a configuration of a data communication system to which the data communication terminal side system is applied. According to the figure, a terminal system 5 having a terminal device 4 is connected to a center system 2 having a center device 1 via a telephone network 3 and a subscribed telephone line L. An electronic meter 6 for reading gas or electricity is connected to a terminal device 4 installed in each house, and a telephone 7 is connected via a telephone line T.
According to the above configuration, the telegram-type meter 6 is connected to the center device 1.
In response to the request or periodically, the meter 4 measures the usage of gas and electricity in each home, and the terminal device 4 transmits the meter reading data to the center device 1 via the subscriber telephone line L.

Since the terminal device 4 is connected to the subscriber's telephone line L, it is usually installed outdoors, such as under the eaves of a house, and a gas or electric telemeter 6 is also installed outdoors. On the other hand, the telephone 7 is installed indoors. Therefore, the connection between the terminal device 4 and the telephone 7 is made by making a hole in the wall 8 of the house.

By the way, as shown in FIG. 5, a dedicated switch 9 is connected to the terminal device 4 for connecting an emergency switch 9 pressed in the event of an emergency such as a gas leak or a fire and a fire sensor for detecting a fire. An input terminal 10 is provided. If an emergency switch 9 or the like is connected to the input terminal 10, a signal input from the emergency switch 9 or the like is transmitted to the center device 1 via the terminal device 4 and the subscriber telephone line L. Therefore, a security system can be easily constructed in a house.

[0005]

However, as described above, the terminal device 4 is installed outdoors, while the emergency switch 9 and the like are installed indoors. Therefore, the terminal device 4
When an emergency switch 9 or the like is connected to the wall, it is necessary to make a hole for a wiring T ′ for connecting the emergency switch 9 to the wall 8 of the house separately from the telephone line T as shown in FIG. is there. Therefore, there is a problem that the construction cost is increased, and it is not preferable in view of the house.

Therefore, as another method of connecting the emergency switch 9 and the like to the terminal device 4, as shown in FIG. 6, another terminal device 11 is newly installed near the telephone 7 which is located indoors.
The emergency switch 9 and the like are connected to the input terminal 12 of the terminal device 11. Then, if communication is performed between another terminal device 11 and the terminal device 4 installed outdoors using the existing telephone line T, a construction for newly piercing the wall 8 of the house is performed. The signal from the emergency switch 9 or the like can be transmitted to the center device 1 without the need. However, in this method, two terminal devices are installed, so that the cost is increased, and furthermore, the terminal device is used only for connecting the emergency switch 9 and the like, which is uneconomical. .

SUMMARY OF THE INVENTION [0007] In view of the above problems, an object of the present invention is to provide a data communication terminal side system in which construction costs and equipment costs are reduced when an indoor emergency switch or the like is connected to an outdoor terminal device.

[0008]

The object of the present invention is to provide a terminal device connected to a subscriber telephone line, a telephone device connected to the terminal device via a telephone line, and a terminal device for transmitting a predetermined input signal to the terminal device. An input device for inputting to the data communication terminal side system, wherein a communication line is used for transmitting a communication signal and an input signal transmission in the communication device, and a communication signal and an input device transmitted through the communication line are used. A detection device is provided for detecting the input signal in a distinguishable manner,
The detection device outputs an input signal to the terminal device.

According to this configuration, on the same call line, the call signal in the call device and the input signal from the input device are distinguished, and only the input signal is output to the terminal device. Using this configuration, the input device is connected to an indoor communication line in parallel with the communication device, and the communication line is used for transmitting the communication signal of the communication device and for transmitting the input signal, and each signal transmitted through the communication line is used. Among them, a detecting device for detecting an input signal from the input device and outputting the signal to the terminal device is provided on an outdoor communication line.

With this configuration, the input signal of the input device is transmitted to the detection device through the communication line, and the detection device detects and distinguishes the communication signal of the communication device and the input signal of the input device. If there is, output it to the terminal device. Therefore, for example, even if the input device is installed indoors near the communication device, the input signal can be output to the terminal device outdoors using the communication line without any trouble. Therefore, it is not necessary to make a new hole in the wall of the house for the wiring for transmitting the input signal as in the related art, and it is not necessary to provide another terminal device indoors.

Further, the detection device may distinguish between a calling signal to the calling device and an input signal, or may distinguish between a calling signal and a calling signal and an input signal.

As a specific configuration of the detecting device, input detecting means for detecting an input signal from the input device based on a current flowing through a communication line, and outputting an input signal to a terminal device based on a detection result by the input detecting means Output control means. More specifically, the input detecting means operates when the first current corresponding to the input signal flows through the communication line.
A current operation unit; and a second current operation unit that operates when a second current corresponding to a speech signal different from the first current flows through the speech line, wherein the output control means includes a first current operation unit and a second current The switching unit outputs an input signal to the terminal device based on the operation state of the operation unit.

According to this configuration, for example, only the first current operation unit is set to operate on the current flowing through the communication line when the input signal from the input device is output to the communication line. Also, the first and second current operation units are set to operate together or the second current operation unit is set to operate according to the current flowing through the communication line when the communication signal of the communication device is output to the communication line. With this configuration, it is possible to easily determine whether the signal output to the communication line is a communication signal or an input signal, depending on the operation state of the first and second current operation units. If the signal is an input signal, the signal is output to the terminal device by the switching unit.

As another specific configuration of the detecting device, when a first current corresponding to the input signal flows through the communication line, the first current detecting unit detects the current and outputs the input signal to the terminal device; It is provided at a stage preceding the first current detector, and when the first current flows through the communication line, passes the current. When the second current corresponding to a communication signal different from the first current flows through the communication line, the current is detected. A second current detection unit that detects and suppresses the operation of the first current detection unit.

According to this configuration, when the input signal flows through the communication line, the input signal is output to the terminal device. In addition, if a call signal flows through the call line, the operation of the first current detection unit is suppressed, so that no input signal is output to the terminal device. Therefore, the input signal and the call signal can be reliably distinguished, and a malfunction is prevented.

The detecting device detects the input signal from the input device based on the current flowing through the communication line, and connects the terminal device and the detecting device when the input signal is detected. And an interruption means for electrically interrupting. Specifically, the shut-off means outputs a short-circuit signal to the terminal device when an input signal is detected, and is open at other times. Therefore, the input impedance of the input-side circuit of the terminal device can be set to 0 or infinity, so that even if the output-side circuit of the detection device exhibits, for example, low impedance, it is possible to prevent the terminal device from being adversely affected. .

Further, as a configuration of the detecting device for detecting the calling signal, an input detecting means for detecting an input signal from the input device based on a current flowing through the telephone line, a calling signal transmitted through the telephone line, Signal detection means for detecting the call signal, and suppression means for suppressing output from the detection device to the terminal device when the call signal detection means detects the call signal. According to this, when the detection device detects the call signal, even if the call signal is erroneously detected as the input signal, the output to the terminal device is suppressed, so that the input signal does not reach the terminal device and the terminal device malfunctions. Never.

Further, the distinction between the call signal and the input signal can be made by software on the terminal device side . End end of the device,
An output signal from the detection device is monitored, and it is determined whether or not the signal is turned on for a predetermined time to recognize the input signal. With this configuration, it is not necessary to provide a means for detecting the call signal in the detection device, so that the configuration of the detection device can be simplified.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

<First Embodiment> The configuration of a data communication system to which a terminal system according to a first embodiment of the present invention is applied is basically the same as the configuration shown in FIG. is there. Therefore, in the following description, FIG.

FIG. 2 is a block diagram showing the configuration of the data communication terminal-side system 5 shown in FIG. In the data communication terminal-side system 5, an emergency switch 9 (input device) is connected indoors to the telephone line T in parallel with the telephone 7 (phone device). The emergency switch 9 detects a gas leak,
A switch that is pressed in the event of an emergency such as a fire, but instead of a sensor for detecting gas or fire,
A switch for activating the terminal device, a sensor for detecting intrusion of a suspicious person, or the like may be connected, and predetermined switches and sensors can be changed as necessary.

An adapter (detection device) 15 for detecting an input signal of the emergency switch 9 sent through the telephone line T outdoors is provided with a telephone line T near the terminal device 4.
It is provided above. Therefore, the terminal device 4 is connected to the telephone 7 via the adapter 15. Also,
The output line 16 from the adapter 15 is connected to the terminal device 4 separately from the communication line T. This output line 16
An input signal detected by the adapter 15 is output, and the input signal is input to the input terminal 10 of the terminal device 4.

FIG. 1 is a diagram showing the internal configuration of the adapter 15 and peripheral devices connected to the adapter 15. In the adapter 15, a first photocoupler 17 (first current operating unit) and a second photocoupler 18 (second current operating unit) as input detection means inserted in series in the communication line T are provided. . The first photocoupler 17 is connected to the communication line T
Is a photocoupler set to operate when a current exceeding a half-loop current (about 1 mA) as a first current corresponding to the input signal flows. The current flows through the LED 17a of the first photocoupler 17. The phototransistor 17b is turned on.

The second photocoupler 18 is a photocoupler set to operate when a loop current (about 20 to 120 mA) as a second current corresponding to a speech signal flows through the speech line T, When the current flows through the LED 18a of the second photocoupler 18, the phototransistor 18b turns on.

A switching transistor 19 as output control means is connected to a stage subsequent to each of the phototransistors 17b and 18b of the first and second photocouplers 17 and 18. Describing the connection configuration in detail, the collector terminal of the phototransistor 17b includes:
The base terminal of a current supply transistor 20 that supplies a current for turning on the switching transistor 19 is connected. The base terminal of the switching transistor 19 is connected to the emitter terminal of the current supply transistor 20. Therefore, when the phototransistor 17b is turned on, the current supply transistor 20 is turned on, a current flows to the base terminal of the switching transistor 19, and the switching transistor 19 is turned on.

The emitter terminal of the current supply transistor 20, that is, the base terminal of the switching transistor 19 is connected to the collector terminal of the phototransistor 18b. Therefore, the phototransistor 18b
Is turned on, the switching transistor 19 is turned off.

The collector terminals of the current supply transistor 20 and the switching transistor 19 are connected to the input terminal 10 of the terminal device 4 connected to the adapter 15 via the output line 16. Input terminal 1 of terminal device 4
0 is internally connected to the inverting circuit 21 and is pulled up to a high level at a predetermined voltage Vcc. Therefore, the input terminal 10 is normally at a high level. An I / O interface (not shown) is connected to the subsequent stage of the inverting circuit 21. The terminal device 4 recognizes that an input signal has been input when the input terminal 10 goes low. In the drawings, reference symbols R1 to R10 indicate current limiting resistors, and C indicates a noise cutting capacitor.

The telephone 7 is provided with a contact 7a that is turned on when the user goes off-hook, and is connected to the telephone line T in series.

In the emergency switch 9, a current limiting resistor R11 is connected to a contact 9a provided therein, and the resistance value of the resistor R11 is determined when the contact 9a is closed.
About 30 to 50 so that the first current value of the half loop current flows through
It is set to kΩ. The contact 9a and the resistor R11
Are connected in parallel to the communication line T.

With such a configuration, when the telephone 7 is used first, that is, when the contact 7a is turned off and the contact 7a is turned on, a loop current corresponding to the second current value, which is relatively large in the communication line T, is equal to the second current value. 2 photo coupler 17,1
8 flows to each LED 17a, 18a. As a result, the phototransistor 17b is turned on, and the current supply transistor 20 is also turned on. At this time, the phototransistor 1
Since 8b is also on, no current flows through the base terminal of the switching transistor 19. Therefore, the switching transistor 19 does not turn on, and the input terminal 10 of the terminal device 4 remains at the high level. Therefore,
The terminal device 4 does not recognize the input signal while using the telephone 7. Note that the terminal device 4 does not recognize an input signal even when the telephone 7 is not in use, since no current flows through the communication line T.

On the other hand, when the emergency switch 9 is pressed, the contact 9a turns on and a half loop current flows through the communication line T. This current is supplied to each LE of the first and second photocouplers 17 and 18.
D17a and 18a, the phototransistor 17b is turned on at this time, but the phototransistor 18b
Does not turn on. Therefore, a base current flows through the switching transistor 19, the switching transistor 19 is turned on, and the input terminal 10 of the terminal device 4 changes from a high level to a low level. Thereby, in the terminal device 4,
It can be recognized that the emergency switch 9 has been pressed. Then, the terminal device 4 automatically makes a call to the center device 1 and transmits emergency information. Alternatively, when the emergency switch 9 is a fire sensor, fire information is transmitted.

As described above, in this embodiment, while an original call can be made using the communication line T, an input signal of the emergency switch 9 installed indoors using the same communication line T is transmitted to the terminal installed outdoors. It can be transmitted to the device 4. Therefore, one communication line T can be used for multipurpose such as transmission of a communication signal and transmission of an input signal. Therefore, a construction in which a hole is newly provided in a house wall to connect the emergency switch 9 is required. There is no need to perform this operation, and there is no need to provide another terminal device near the indoor telephone 7. Therefore, when connecting the indoor emergency switch 9 to the outdoor terminal device 4, it is only necessary to arrange the adapter 15 near the outdoor terminal device 4, and it is possible to provide a terminal system that can be realized at low cost. . Note that the above-described distinction between the call signal and the input signal may be made by software.

When a call signal arrives at the telephone 7, a call signal is usually input to the telephone 7 first. The ringing signal is a ringer signal of AC 75 V, 16 Hz, and the ringer signal is usually repeated for one second and the pause is repeated for two seconds. When the ringer signal of AC 75 V, 16 Hz is input to the telephone 7, in the circuit shown in FIG. 1, a current equivalent to an impedance of 2 KΩ or more, that is, a current equivalent to a half loop may flow through the communication line T.

Therefore, the photo-coupler 17 is turned on (the photo-coupler 18 is turned off) by the current corresponding to the half loop, and the switching transistor 19 is accordingly turned on.
Was turned on, and a signal indicating that the emergency switch 9 was pressed was output from the adapter 15 to the terminal device 4 even though the emergency switch 9 was not pressed.
Therefore, here, a circuit for detecting a call signal is newly provided, and the output of the switching transistor 19 is suppressed by the output of the circuit. Specifically, FIG.
As shown in FIG. 3, a ringer detecting circuit 2 as a calling signal detecting means is provided on a communication line T between the terminal device 4 and the adapter 15.
3 are connected in parallel, and a switch 24 is connected to the subsequent stage of the second photocoupler 18 as a suppressing means that operates so as to suppress the operation of the switching transistor 19 when the ringer detecting circuit 23 detects the ringing signal.

The ringer detection circuit 23 is a known circuit, and a circuit normally built in the telephone 7 may be used.
The switch 24 is, for example, a contact switch of a relay (not shown) built in the ringer detection circuit 23. In addition,
The ringer detection circuit 23 may be built in the adapter 15 or may be built in a unit provided separately from the adapter 15.

In operation, the ringer detection circuit 23
Receives the ringing signal, detects the ringer signal of AC 75 V, 16 Hz, and turns on the switch 24. As a result, the collector current of the current supply transistor 20 does not flow to the base terminal of the switching transistor 19, that is, the base and the emitter of the switching transistor 19 are short-circuited, and the operation of the switching transistor 19 is suppressed. Therefore, it is not output from the adapter 15 to the terminal device 4.

On the other hand, when the emergency switch 9 is pressed or when the telephone 7 enters the talking state, the ringer detection circuit 23 does not operate, so that the switch 24 is not turned on. Therefore, the switching transistor 19 becomes operable.

As described above, when a calling signal is input to the telephone 7, it is possible to prevent the adapter 15 from erroneously detecting the calling signal as a signal due to the pressing of the emergency switch 9 and outputting the signal to the terminal device 4. Therefore, the call signal to the telephone 7 and the signal due to the pressing of the emergency switch 9 can be reliably distinguished, and the terminal device 4 is prevented from erroneously calling the center device 1 by the call signal.

Further, instead of the ringer detection circuit 23, the terminal device 4 may use software to distinguish between a call signal to the telephone 7 and a signal due to the pressing of the emergency switch 9.

Specifically, in the terminal device 4, a signal input from the input terminal 10 is sampled and monitored continuously for a predetermined time. Then, the predetermined time is set longer than the ringer time (1 second) of the call signal. Then, when a call signal is input to the telephone 7, the adapter 1
5 erroneously outputs to the terminal device 4 a signal indicating that the emergency switch 9 has been pressed, but since this signal is always turned off once during the above-mentioned predetermined time, it is easily recognized as a calling signal. can do. However, in this case, it is necessary for the user to press the emergency switch 9 for a longer time than the ringer time in order to distinguish the call signal from the signal generated by pressing the emergency switch 9.

FIG. 8 is a flowchart showing the processing operation of the terminal device 4 when discriminating between a calling signal and a signal due to the pressing of the emergency switch 9. First, in the terminal device 4, the input signal from the input terminal 10 is transmitted at a certain period (several msec).
And waits until the contact signal is turned on (step S1). At this time, if the contact signal is off, the process proceeds to the main routine (step S2).

Next, when the emergency switch 9 is pressed or a call signal is input to the telephone 7, the contact signal is turned on. Therefore, the terminal device 4 outputs the contact signal from the input terminal 10 for a predetermined time (for example, 2 seconds). Monitor (step S3).
At this time, the terminal device 4 masks the contact signal from the input terminal 10 and does not take it inside. Then, it is determined whether or not the contact signal continues for a predetermined time (step S).
4).

If the contact signal does not continue to be turned on in step S4, it is determined that a call signal has been input to the telephone set 7, and the process proceeds to the main routine of step S2. On the other hand, if the contact signal continues, the terminal device 4 determines that the emergency switch 9 has been pressed, cancels the mask, and takes in the contact signal from the input terminal 10. Then, the terminal device 4 performs a call operation to the center device 1 (step S5).

As described above, the calling signal to the telephone 7 and the signal due to the pressing of the emergency switch 9 can be easily determined by software. Therefore, the ringer detection circuit 23 and the switch 2 shown in FIG.
4 is not required, and the cost of parts can be reduced.

In the process of step S3, it may be determined whether or not the contact signal is turned on for more than one second within a predetermined time.

<Second Embodiment> In the circuit shown in FIG. 1 of the first embodiment, when the telephone 7 is used for a telephone call, the first and second photocouplers 17 and 18 are simultaneously turned on. The circuit on the output side of the adapter 15 is configured by combining resistors, transistors, and the like.
Is changed from high impedance to low impedance of several hundred KΩ. Therefore, if the terminal device 4 erroneously recognizes that the load is connected, and the sampling circuit (not shown) in the terminal device 4 performs the sampling operation, the current consumption of the terminal device 4 may increase during the operation. .

Also, the terminal device 4 has an input terminal 1 due to a drop in impedance due to the circuit configuration on the input side.
The logic of the signal at 0 may be inverted and recognized. For example, in the case of the circuit configuration on the input side of the terminal device 4 shown in FIG. 1, the resistance value of the pull-up resistor R5 and the adapter 1
5 is an input threshold level for determining the high level or the low level of the inverting circuit 21. Therefore, when the input impedance of the terminal device 4 becomes low, the input threshold level decreases, and the logic of the contact signal may be erroneously detected. As a result, the terminal device 4 may erroneously call the center device 1 simply by using the telephone 7 by the user.

Therefore, in the second embodiment, the circuit configuration on the output side of the adapter 15 with respect to the terminal device 4 is configured not to exhibit a low impedance value of, for example, several hundred KΩ, so that the power consumption of the terminal device 4 is reduced. It prevents an increase and erroneous detection of a contact signal.

FIG. 9 shows an adapter 25 according to the second embodiment.
FIG. 2 is a diagram showing an internal configuration of the device and peripheral devices connected to an adapter 25. The adapter 25 includes a rectifying bridge 26 inserted in series in the communication line T, a loop current detecting circuit 27 connected downstream of the rectifying bridge 26, and a half loop current detecting circuit connected downstream of the loop current detecting circuit 27. 2
8 is provided.

When a half-loop current detecting circuit 28 as a first current detecting section flows through the telephone line T when a half-loop current corresponding to the input signal flows, the half-loop current detecting circuit 28 detects the current and outputs an input signal to the terminal device 4. Has functions. The loop current detection circuit 27 as a second current detection unit is provided at a stage preceding the half loop current detection circuit 28, and when a half loop current flows through the communication line T, allows the current to pass therethrough. Has a function of detecting the current when the current flows through the communication line T to suppress the operation of the half-loop current detection circuit 28.

The half-loop current detection circuit 28 conducts the terminal device 4 and the adapter 25 when an input signal is detected,
At other times, it has a cutoff function to cut off electrically.
Specifically, a short-circuit signal is output to the terminal device 4 when an input signal is detected, and the terminal device 4 is opened at other times.

The loop current detection circuit 27 includes a photocoupler 29 that operates when a current exceeding the loop current (about 20 to 120 mA) as the second current flows through the communication line T, and two current limiting resistors R13 and R13. R14. One end of each of the resistors R13 and R14 is connected to the rectifying bridge 26, and the other end is connected to both ends of the photodiode 29a of the photocoupler 29. The cathode side of the photodiode 29a is connected to the collector terminal of the phototransistor 29b. Note that the resistors R13, R
The resistance values of 14 may be 80Ω and 150Ω, respectively.

The half loop current detection circuit 28
The photocoupler 30 operates when a current exceeding a half loop current (about 1 mA) as the first current flows, and two current limiting resistors R15 and R16. Resistance R1
Both ends of 5 are connected to the collector and emitter terminals of the phototransistor 29b of the loop current detection circuit 27, and are also connected to one end of the resistor R16 and the cathode terminal of the photodiode 30a of the photocoupler 30.
The other end of the resistor R16 is connected to the anode terminal of the photodiode 30a. The output of the phototransistor 30b of the photocoupler 30 is connected to the input terminal 10 of the terminal device 4. Note that the resistance values of the resistors R15 and R16 may each be 1 kΩ. In the figure, R12 is a current limiting resistor, and the other configuration is the same as that of the first embodiment.

With these configurations, when the emergency switch 9 is pressed and a half-loop current of about 1 mA flows through the communication line T, the photocoupler 30 of the half-loop current detection circuit 28 turns on. That is, the photodiode 30a is turned on and the phototransistor 30b is turned on, and the collector and emitter terminals are short-circuited. At this time, the photodiode 29a of the photocoupler 29 does not turn on because the value of the flowing current is small.

When the collector and emitter terminals of the phototransistor 30b are short-circuited, the terminal device 4
The input of the inverting circuit 21 changes from high level to low level. Therefore, the terminal device 4 can recognize that the emergency switch 9 has been pressed.

On the other hand, when the telephone 7 is
When a mA loop current flows through the communication line T, the photodiode 29a of the loop current detection circuit 27 turns on, and the phototransistor 29b turns on accordingly. As a result, the collector and emitter terminals of the phototransistor 29b are short-circuited, and the half-loop current detection circuit 28
Is suppressed. That is, the photodiode 30
Since a cannot be turned on, the signal is not output from the adapter 25 to the terminal device 4, and the high level state is maintained at the input terminal 10 of the terminal device 4. Therefore, no call is sent from the terminal device 4 to the center device 1.

As described above, the adapter 25 of the second embodiment
Thus, the speech signal and the input signal can be distinguished. Also, since only the phototransistor 30b is connected to the input terminal 10 of the terminal device 4, the output of the phototransistor 30b is short-circuited when turned on, and the output is opened when turned off.
5 does not show low impedance.

Therefore, the circuit configuration in the adapter 25 prevents the input impedance of the terminal device 4 from becoming low when the telephone 7 is used, so that current consumption is not wasted at the time of sampling.
Further, since the input threshold level of the inverting circuit 21 is not changed, the possibility of erroneously detecting and recognizing the logic of the input signal can be greatly reduced.

Furthermore, by making the circuit configuration on the output side of the adapter 25 a simple configuration such as only a phototransistor, the circuit configuration on the input side of the terminal device 4 can also be simplified. Therefore, the number of connectable terminal devices is increased, and the versatility of the adapter 25 is expanded. Moreover, it can be manufactured at low cost.

The output side of the adapter 25 and the terminal device 4
May be connected wirelessly. Then, when no signal is transmitted wirelessly, the adapter 25 and the terminal device 4 are completely disconnected.

Incidentally, also in the second embodiment,
A circuit for detecting a call signal may be provided, and an output signal thereof suppresses an output signal from the adapter 25 to the terminal device 4 so that a call signal to the telephone 7 and a signal due to pressing of the emergency switch 9 may be distinguished. .

More specifically, as shown in FIG. 10, a call signal detection circuit 31 is connected in parallel to a communication line T between the terminal device 4 and the adapter 25, and a call current detection circuit 27 The phototransistor 3 of the photocoupler 32 as a suppression means that operates to suppress the signal from the communication line T when the signal detection circuit 31 detects the calling signal.
2b is connected.

More specifically, both ends of the collector and the emitter terminal of the phototransistor 32b of the photocoupler 32 are connected to both ends of the collector and the emitter terminal of the phototransistor 29b of the photocoupler 29 of the loop current detection circuit 27, respectively. Both ends of the resistor R15 of the half loop current detection circuit 28 are connected.

In the calling signal detecting circuit 31, a current limiting resistor R17, a Zener diode D1 for cutting off a signal of AC 50 V or less, a rectifying bridge 33, an AC 75
Capacitors C1 for detecting V and 16 Hz ringer signals are connected in series to the communication line T, respectively.
A Zener diode D2 is connected to both ends of the rectifier bridge 33.
And an electrolytic capacitor C2 are connected in parallel.
The photocoupler 32 is connected in parallel via the current limiting resistor R18. Zener diode D2 is also AC50
This is for cutting the signal below V, and the electrolytic capacitor C2 is for smoothing the AC signal rectified by the rectification bridge 33. Therefore, in the ringing signal detecting circuit 31, the ringer detecting circuit 23 of the first embodiment is used.
Unlike this, a ringing signal can be detected not only when a ringer signal of AC75V, 16 Hz for 1 second arrives but also for a pause of 2 seconds. Note that the call signal detection circuit 31 may be built in the adapter 25 or may be provided in an independent unit.

With this configuration, when a calling signal is input to the telephone 7, the photodiode 32a is turned on and the phototransistor 32b is turned on. Thereby, the operation of the photocoupler 30 is suppressed, and the terminal device 4
Is not output to

As described above, the operation of the half-loop current detection circuit 28 can be suppressed by the call signal detection circuit 31, so that the call signal to the telephone 7 and the emergency switch 9
Can be distinguished from the signal due to the pressing of Therefore, it is possible to prevent the adapter 25 from erroneously detecting the call signal as a signal due to the pressing of the emergency switch 9.

Also in the second embodiment, the ringer signal of the call signal and the signal by pressing the emergency switch 9 are distinguished by the software shown in the first embodiment instead of the call signal detection circuit 31. You may do so.

In the configuration inside the adapters 15 and 25, since a photocoupler or a rectifying bridge is inserted in series in the communication line T, the original voice communication can be performed without any trouble. Further, since no voltage is applied to the telephone network 3, there is no influence on the exchanges and other calls in the telephone network 3.

The present invention is not limited to the above embodiment, and many modifications and changes can be made to the above embodiment within the scope of the present invention. For example, as shown in FIG. 3, a contact signal (such as the input signal or the like) from the terminal device 4 via the communication line T is transmitted from the terminal device 4 to the gas shutoff device 22 which is provided indoors and shuts off the gas supply when there is a gas leak. In this case, for example, when it is desired to send a gas shutoff command signal, the adapter 15 may be provided on the communication line T near the telephone 7, and the output line 16 may be connected to the gas shutoff device 22. When a gas cutoff command signal is sent from the terminal device 4 side, if a half loop current is caused to flow through the communication line T, the adapter 15 can detect the gas cutoff command signal, Signal can be given. In this way, by changing the insertion position of the adapter 15 on the communication line T, it is possible to send a signal different from the communication signal from the outdoor side to the indoor side through the communication line T.

The circuit in the adapter 15 may be provided integrally in the terminal device 4 or in the telephone 7 in the case of the configuration shown in FIG. that way,
The construction cost for wiring can be reduced.

Further, the first and second current operation units
Instead of the photocouplers 17 and 18, an overcurrent relay or the like that operates when a current exceeding a predetermined current value is detected may be used. Instead of detecting the value of the current flowing through the telephone line T, the value of the impedance in the telephone line T may be detected. Further, the ringer detection circuit, the half loop current detection circuit, and the loop current detection circuit may be configured by a current sensor such as a Hall element.

[0071]

As described above, according to the present invention, the input signal of the input device connected in parallel with the communication device to the communication line is transmitted to the detection device through the communication line. And the input signal from the input device is distinguished and detected, and if it is an input signal, it is output to the terminal device. For example, even if the input device is installed indoors near the telephone device, it can be used outdoors by using the telephone line. The input signal can be output to the terminal device without any trouble. Therefore, the telephone line can be used for multipurpose of transmitting a telephone signal and transmitting an input signal, and it is not necessary to make a hole in a wall of a house for wiring for transmitting an input signal as in the related art. It is not necessary to newly provide a terminal device. Therefore, when an indoor input device is connected to an outdoor terminal device, it is possible to provide a data communication terminal-side system with reduced cost.

In the detection device, since only a photocoupler or a rectifying bridge is inserted in series in a communication line, the original voice communication can be performed without any trouble. Also, since no voltage is applied to the telephone network,
It has no effect on exchanges or other calls in the telephone network.

In addition to discriminating between the call signal and the input signal, the detection device can discriminate the call signal to the call device from the input signal, or can discriminate the call signal and the call signal from the input signal. Since the output from the detection device to the terminal device is suppressed when a call signal that may be mistaken for the input signal is detected, it is possible to prevent the input signal from being erroneously output to the terminal device as having been input. Therefore, the reliability of the detection device can be improved.

Further, the detection device conducts the terminal device and the detection device when an input signal is detected, and electrically disconnects the detection device at other times. Therefore, the impedance of the circuit on the input side of the terminal device becomes 0 or infinity. It is possible to prevent an increase in power consumption of the terminal device due to a low input impedance of the terminal device other than when an input signal is detected. Also, the terminal device does not invert the logic of the input signal for recognition. In addition, since the circuit configuration on the output side of the detection device can be simplified, for example, a phototransistor, the circuit configuration on the input side of the terminal device can also be simplified. Therefore, the possibility that the detection device can be connected to various terminal devices is increased, and the versatility of the device is expanded.

Further, since the distinction between the calling signal and the input signal can be made by software in the terminal device, the configuration of the detecting device can be simplified and the device can be downsized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an internal configuration of an adapter according to a first embodiment of the present invention and a connection configuration with peripheral devices.

FIG. 2 is a diagram showing a configuration of a data communication terminal side system.

FIG. 3 is a diagram showing a configuration of a data communication terminal-side system according to another embodiment.

FIG. 4 is a diagram showing a configuration of a conventional data communication system.

FIG. 5 is a diagram showing a configuration of a conventional data communication terminal-side system.

FIG. 6 is a diagram showing another configuration of a conventional data communication terminal-side system.

FIG. 7 is a diagram showing a modification of the first embodiment;

FIG. 8 is a flowchart showing a processing operation of the terminal device.

FIG. 9 is a diagram showing an internal configuration of an adapter according to a second embodiment and a connection configuration with a peripheral device.

FIG. 10 is a diagram showing a modification of the second embodiment.

[Explanation of symbols]

4 Terminal device 7 Telephone 9 Emergency switch 15, 25 adapter 17 1st photo coupler 18 2nd photocoupler 19 Switching transistor 23 Ringer detection circuit 24 switches 27 Loop current detection circuit 28 Half loop current detection circuit 31 Call signal detection circuit L Joined telephone line T telephone line

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H04M 11/00 H04Q 9/00 G08C 13/00

Claims (13)

(57) [Claims] 1. A terminal device connected to a subscriber telephone line,
A communication device connected to the terminal device via a communication line,
A data communication terminal system including an input device for inputting a predetermined input signal to the terminal device, wherein the communication line is used for transmitting a call signal to the communication device and for transmitting an input signal, A data communication device, further comprising a detecting device for distinguishing and detecting the calling signal and an input signal from the input device transmitted through the communication line, wherein the detecting device outputs the input signal to the terminal device. Terminal side system. 2. A terminal device connected to a subscriber telephone line,
A communication device connected to the terminal device via a communication line,
An input device for inputting a predetermined input signal to the terminal device, the data communication terminal-side system comprising: a communication line for transmitting a communication signal or a call signal of the communication device and an input signal. A detecting device for distinguishing and detecting the call signal and the call signal and an input signal sent from the input device through the call line, and the detecting device outputs the input signal to the terminal device. A terminal system for data communication characterized by the following. 3. An outdoor terminal device connected to a subscriber telephone line, an indoor communication device connected to the terminal device via a communication line, and an input for inputting a predetermined input signal to the terminal device. A data communication terminal-side system comprising a device, wherein the input device is connected to the indoor communication line in parallel with a communication device, and the communication line is used for transmitting a communication signal or a call signal of the communication device. A detecting device for transmitting an input signal and detecting an input signal from the input device among signals transmitted through the communication line and outputting the signal to the terminal device is provided on the communication line outdoors. Terminal system for data communication. 4. A detecting device for detecting an input signal from an input device based on a current flowing through a communication line, and outputting the input signal to a terminal device based on a detection result by the input detecting device. 4. The terminal system for data communication according to claim 2, further comprising an output control unit. 5. An input detecting means, comprising: a first current operating section that operates when a first current corresponding to an input signal flows through a communication line; and a second current corresponding to a communication signal different from the first current. A second current operation unit that operates when the current flows through the telephone line; and an output control unit that outputs the input signal to a terminal device based on an operation state of the first current operation unit and the second current operation unit. 5. The data communication terminal-side system according to claim 4, comprising a unit. 6. A first current detector for detecting a first current corresponding to an input signal when the current flows through a communication line and outputting the detected current to a terminal device, and a preceding stage of the first current detector. Is provided, when the first current flows through the communication line, passes the current, and when a second current corresponding to a communication signal different from the first current flows through the communication line, the current is detected. 3. The apparatus according to claim 2 , further comprising a second current detecting unit for suppressing an operation of said first current detecting unit.
4. The terminal system for data communication according to claim 3 . 7. A detection device, comprising: input detection means for detecting an input signal from an input device based on a current flowing through a communication line; and conducting between a terminal device and the detection device when the input signal is detected. 4. The data communication terminal-side system according to claim 2, further comprising a disconnection unit for electrically disconnecting the data communication terminal. 8. The data communication terminal-side system according to claim 7 , wherein the shut-off means outputs a short-circuit signal to the terminal device when an input signal is detected, and is opened at other times. 9. A detection device, comprising: an input detection means for detecting an input signal from the input device based on a current flowing through a communication line; a call signal detection means for detecting a call signal transmitted through the communication line; The apparatus according to claim 1, further comprising a suppression unit that suppresses output from the detection device to the terminal device when the call signal detection unit detects the call signal .
4. The terminal system for data communication according to 2 or 3 . 10. A detection device, comprising: input detection means for detecting an input signal from an input device based on a current flowing through a communication line; and outputting the input signal to a terminal device based on a detection result by the input detection means. Output control means, a call signal detection means for detecting a call signal transmitted through a telephone line, and a signal provided between the input detection means and the output control means. claim 1, wherein the terminal side system for data communication, characterized in that it comprises a suppression means for suppressing the output to the output control means. 11. A detection device, comprising: an input detection means for detecting an input signal from the input device based on a current flowing through a communication line; a call signal detection means for detecting a call signal transmitted through the communication line; provided before the input detection means, the data communication terminal according to claim 1, wherein characterized in that it comprises a suppression means for suppressing the input signal from the communication line when detecting a call signal Side system. 12. end end device claims, characterized in that it comprises recognition means for the signal to monitor the output signal from the detection device for recognizing an input signal to determine whether to turn on a predetermined time 4. The terminal system for data communication according to any one of 1 to 3 . 13. The detecting device according to claim 1, wherein said detecting device is in a terminal device,
2. The apparatus according to claim 1, wherein the apparatus is integrally provided in the apparatus.
13. The terminal system for data communication according to any one of
Tem.