JPH0799557B2 - Gas leak alarm - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a gas leak alarm system having a function of notifying an administrator via a telephone line when a gas leak is detected.

<Prior Art> A conventional gas leak alarm is provided with a detection unit for detecting a gas leak, and a control unit for notifying an administrator of a signal output from the detection unit via a telephone line. A gas leak reporting means for reporting a gas leak signal from the detection section to an administrator via a telephone line; and a detection section abnormality reporting means for reporting an abnormal signal of the detection section itself to the administrator via a telephone line. And a resend requesting unit for requesting the sensing unit malfunction reporting unit to resend the sensing unit malfunction signal when the sensing unit malfunction reporting unit is unsuccessful.

That is, the detection unit performs the output of the two-stage voltage system,
For example, a 6V signal is output to the output terminal when normal, and a 12V signal is output when gas leak is detected. Then, when a gas leak is detected, the control unit notifies the administrator of the gas leak via the telephone line.

At this time, the control unit is driven by the battery, and the detection unit is driven by the commercial AC power supply. Therefore, when the power supply of the detection unit is cut off due to a power failure or intentionally or accidentally, the output of the detection unit becomes 0V and is detected by the control unit as an abnormal signal of the detection unit itself.

When the detection unit abnormality signal is detected, the control unit notifies the administrator of the detection unit abnormality via the telephone line. At this time, if the notification to the administrator is unsuccessful due to busy or the like, the retransmission is repeated every fixed time (about 1 minute) until the notification is successful.

Next, a case where a regional blackout occurs in this system will be described.

As shown in Fig. 6, when a regional blackout occurs (point A in the diagram),
Hundreds and thousands of gas leak alarms in the area will attempt to report to the control center all at once. However, the control center usually has only 3 to 4 telephone lines, and only a few gas leak alarms succeed in reporting (B
However, most of the gas leak alarms have failed to communicate with the management center (point C), and are repeatedly retransmitted.

<Problems to be solved by the invention> Therefore, the telephone of the management center is out of power (D
It continues to be in a congested state until (point), and even if there is a gas leak outside the power outage area, it can not be detected, it becomes difficult for general subscribers in the relevant telephone central office to make a call, and when it causes a lot of trouble, there is a problem. is there.

On the other hand, there is a system in which the detection unit abnormality signal is not transmitted to the management center in order to prevent the occurrence of the above problems. However, in such a system, when the user intentionally pulls out the power plug to prevent malfunction, if this cannot be detected, there is a serious safety problem.

Therefore, the present invention can distinguish between the case of a regional blackout and the case where one detection unit is abnormal, and can prevent the telephone line of the administrator from being congested for a long time even in the case of a regional blackout. The purpose of the present invention is to provide a highly safe gas leak alarm system that can reliably detect gas leaks in other areas.

<Means for Solving Problems> The problem solving means according to the present invention is, as shown in FIGS. 1 to 5, a detector 1 for detecting a gas leak, and an output signal of the detector 1 for a telephone line 2. In a gas leak alarm device provided with a control unit 3 for notifying an administrator via a telephone, and the control unit 3 sends a gas leak signal from the detection unit 1 to the telephone line 2. Gas leak reporting means 4 for notifying the administrator via the detector, and detector abnormality notification for detecting that the power to the detector 1 is cut off and notifying the administrator of the detector power supply abnormal signal via the telephone line 2. Means 5, resending request means 6 for requesting the sensing portion abnormality reporting means 5 to resend the sensing portion power source abnormality signal when the notification of the sensing portion abnormality reporting means 5 is unsuccessful, and detection by the resending requesting means 6 Part abnormality reporting means 5
Of the detection unit power supply abnormality signal, and the number of retransmissions of the detection unit power supply abnormality signal of the detection unit abnormality notification unit 5 counted by the retransmission count counting unit 7 is a constant value. When it exceeds, it is determined that the cause of the detection unit power supply abnormality signal is a regional power outage, and the resending operation is stopped.

<Operation> In the above problem solving means, when an abnormality such as the power supply being cut off occurs in the detection unit 1, the detection unit 1 is controlled by the control unit 3.
The detection unit abnormality signal is transmitted to. Control unit 3 which received this
Informs the administrator that an abnormality has occurred in the detection unit via the telephone line 2 using the detection unit abnormality notification means 5.

At this time, when the communication is unsuccessful because the line is not connected due to busy or the like, the resending request means 6 requests resending at regular time intervals, and the resending number counting means 7 counts the number of resending requests. When the number of retransmissions exceeds a certain limit, the retransmission number limiting means 8 causes the retransmission requesting means 6 to stop the retransmission operation.

That is, when a regional power outage occurs, all alarm devices in the area attempt to notify the administrator, and all the lines owned by the administrator are closed at the same time. However, many other gas leak alarms are also trying to report to the administrator by repeating the re-sending for a certain number of times, and it is determined that the cause of the abnormal signal of the detection unit is the regional power outage, so the line cannot be used for a long time. When is blocked, the condition does not persist.

Therefore, the administrator can distinguish between the case of regional power outage and the case where one detection unit is abnormal, depending on the blocked state of the telephone line, and the telephone line of the administrator is congested for a long time even in the case of regional blackout. It is possible to provide a highly safe gas leak alarm system that can prevent a situation from occurring and can reliably detect even if a gas leak occurs in another area.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a functional block diagram showing the gas leak alarm device of the present invention, FIG. 2 is the same system configuration diagram, FIG. 3 is the same electric circuit diagram of the control unit, and FIG. 4 is the same one detection unit. FIG. 5 is a diagram showing a waveform transmitted to the management center in the case of No. 5, and FIG. 5 is a diagram showing a waveform transmitted to the management center when a regional blackout similarly occurs.

Then, as shown in the figure, the gas leak alarm device of the present invention is provided with a detection unit 1 for detecting a gas leak and a control unit 3 for notifying an administrator of an output signal of the detection unit 1 via a telephone line 2. In the gas leak alarm device installed at a plurality of locations, the control unit 3 reports the gas leak signal from the detection unit 1 to a manager via a telephone line 2, and the gas leak reporting unit 4; The detection unit abnormality notifying means 5 for detecting that the power supply to the detection unit 1 is cut off and notifying the administrator of the detection unit power supply abnormality signal via the telephone line 2 and the notification of the detection unit abnormality notifying means 5 are unsuccessful. Resending request means 6 for requesting the resending of the sensing portion power source abnormality signal to the sensing portion abnormality reporting means 5 in the case of success,
The resending request counting means 6 counts the number of times the sensing section power failure signal is resent by the resending requesting means 6, and the sensing section malfunction reporting means 5 counted by the resending number counting means 7. When the number of times the detection unit power supply abnormality signal is retransmitted exceeds a predetermined value, it is determined that the cause of the detection unit power supply abnormality signal is a regional power failure, and the retransmission number limiting unit 8 is provided to stop the retransmission operation.

The detection unit 1 is the same as the conventional one, has a function of detecting a gas leak using the gas sensor 9, and is driven by a commercial AC power supply AC. Then, the output terminal 10 of the detection unit 1 outputs a voltage of, for example, normally 6V and 12V when a gas leak is detected as a two-stage voltage-applied method.

As shown in FIG. 3, the control unit 3 has a general CMOS type one-chip microcomputer 11, and the re-transmission requesting unit 6, the re-transmission number counting unit 7 and the re-transmission number limiting unit 8 include the micro computer 11. It is composed of
The microcomputer 11 has a central processing unit (CP
It has a U) 12, a read-only storage device (ROM) 13, a writable storage device (RAM) 14, an input / output device (I / O) 15, and is driven by a lithium battery 16.

Then, the I / O 15 is connected with the communication device 17 as the gas leak reporting means 4 and the detector abnormality reporting means 5,
Further, the detection unit 1 is connected via a first comparator 18 and a second comparator 19. Here, the negative logic side input terminal which is the comparison reference voltage of the first comparator 18 is applied with a voltage of about 9V which is an intermediate between 6V which is a normal signal and 12V which is a gas leak detection signal, and The negative logic side input terminal which is the comparison reference voltage of the two comparators 19,
The values of the resistors R1 to R4 are selected so that a voltage of about 3V which is between the normal signal of 6V and the detection unit abnormality signal of 0V is applied.

Then, the communication device 17 is connected to the microcomputer.
Management center via telephone line 2 based on request from 11
It has a function of calling 20 receivers 21 and transmitting a gas leak detection signal or a detection unit abnormality signal.

In FIG. 2, 22 is a user's house, 23 is a telephone station, and 24 is a cable connecting the detection unit 1 and the control unit 3.

In the above configuration, first, the case where the detection unit 1 detects a gas leak will be described.

When the detector 1 detects a gas leak, its output terminal 10
The voltage of 12V is detected as the gas leak detection signal. Then, the outputs of the first comparator 18 and the second comparator 19 of the control unit 3 are both at the “H” level, and the microcomputer 11 knows that the detection unit 1 has detected the gas leak,
The communication device 17 is used to call the receiver 21 of the management center 20 via the telephone line 2 to notify that a gas leak has occurred.
Upon receiving this, the management center 20 urgently calls the user or rushes to the site.

Next, a case where one gas leak alarm device generates a detection part abnormality signal will be described with reference to FIG.

When the power of the detection unit 1 is turned off (point A in the figure) or the cable 24 connecting the detection unit 1 and the control unit 3 is disconnected, the voltage input to the control unit 3 becomes 0V and the detection unit abnormality signal is output. Occur. Then, both outputs of the first comparator 18 and the second comparator 19 become "L" level, and the microcomputer 11 knows that the detector abnormal signal is generated, and uses the communication device 17 to set the receiver 21 of the management center 20. A call detector is informed that an abnormality has occurred (point B). Upon receipt of this, the management center 20 responds by urgently calling the user or the like, and depending on the result, restores the power to the user (point D) or goes on-site to repair the gas leak alarm. Perform processing such as going out.

Next, a case where a regional blackout occurs will be described with reference to FIG.

When a regional blackout occurs (point A in the figure), all (hundreds or thousands) of gas leak alarms in the blackout area report to the management center 20 at once as an abnormal detector signal. Try. At this time, the management center 20 normally has only a few lines, so it was luckily successful in reporting (B
Most of the gas leak alarms, except for some of the above, failed to report (point C) and try to report again after a fixed time (for example, 1 minute). However, even at this time, since many gas leak alarms that failed to report first try to report at the same time, most gas leak alarms still fail to report, and after a certain time, report again. Try.

In the case of the conventional gas leak alarm device, the retransmission is repeated until the notification is successful here. However, when the gas leak alarm device of the present invention counts the number of times of retransmission and repeats the retransmission for a certain number of times (for example, 2 times), The control unit 3 is also attempting to notify the management center 20 of a number of other gas leak alarms at the same time, determines that the cause of the detection unit abnormality signal is a regional power outage, and suspends the resending operation.

At this time, in the management center 20, all the lines owned are
At the same time, it is blocked for a certain number of times at a certain time interval, so these detection unit abnormality signals are due to regional blackouts.
It can be judged that there is no urgent need to take any action.

As a result, even if a regional power outage occurs, the telephone line 2 of the management center 20 does not remain in a congested state for a long time until the power outage ends (point D), and even if a gas leak occurs in another area, it can be detected. it can.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

For example, if the detection unit abnormal signal is not resolved even after a relatively long fixed time (for example, 3 hours) after the resending operation is stopped (when the power outlet of the detection unit 1 is unplugged during a power outage, etc.), it is resent again. The control unit 3 may be provided with a re-transmission resuming means for starting the operation.

<Effects of the Invention> As is apparent from the above description, according to the present invention, when the number of times of resending the detection unit power supply abnormality signal caused by the power supply to the detection unit being cut off becomes a constant value, the cause of the abnormality of the detection unit Has determined that there is a regional blackout.

Therefore, since the retransmission operation is stopped by making such a determination, it is possible to prevent a state in which the telephone line is blocked for a long time.

In addition, the administrator can distinguish between the case of regional power outage and the case where one detection unit is abnormal due to the blocked state of the telephone line, and even in the case of regional power outage, the telephone line of the administrator is congested for a long time. It can be prevented, and even if a gas leak occurs in other areas, it can be reliably detected.

Moreover, since this abnormality is due to a power outage, it is possible to eliminate the need for the administrator to take any action and eliminate unnecessary work, and it is possible to provide a highly safe gas leak alarm system. .

[Brief description of drawings]

FIG. 1 is a functional block diagram showing the gas leak alarm device of the present invention.
Fig. 2 is a system configuration diagram, Fig. 3 is an electric circuit diagram of the control unit, and Fig. 4 is a diagram showing waveforms transmitted to the control center when one detection unit is abnormal. FIG. 5 is a diagram showing a waveform transmitted to the management center when a regional power outage occurs, and FIG. 6 is a diagram showing a waveform transmitted to the management center when a regional power outage occurs in the conventional gas leak alarm. Is. 1: detection unit, 2: telephone line, 3: control unit, 4: reporting unit, 5: detection unit abnormality reporting unit, 6: retransmission request unit, 7: number of retransmissions counting unit, 8: number of retransmissions limiting unit, 9: Gas sensor, 11: Microcomputer, 16: Battery, 17: Communication device, 20: Management center, 21: Receiver, 22: User's house, 23: Telephone office.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kimio Nakagawa 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Co., Ltd. (56) -186995 (JP, A) JP 61-239761 (JP, A) JP 61-166699 (JP, A)

Claims (1)

[Claims] 1. A gas leak alarm provided with a detection unit for detecting a gas leak and a control unit for notifying an administrator of an output signal of the detection unit via a telephone line, and installed at a plurality of locations. In the above, the control unit detects the gas leak signal from the detection unit to a manager via a telephone line and a gas leak notification unit that detects that the power supply to the detection unit is cut off, and detects a power failure of the detection unit. A detection unit abnormality notifying means for notifying a signal to an administrator via a telephone line, and requesting the detection unit abnormality notifying means to resend the detection unit power supply abnormality signal when the notification of the detection unit abnormality notifying means is unsuccessful A resending request means, a resending number counting means for counting the number of times of resending of the sensing unit power source abnormality signal of the sensing unit abnormality reporting unit by the resending requesting unit, and the sensing unit abnormality reporting unit counted by the resending number counting unit. Detection Gas leak alarm number of retransmissions of the power failure signal is characterized by having a retransmission count limit means for stopping the determination retransmits operate as a local power failure causes the detection unit power failure signal exceeds a predetermined value.