JP3153014B2 - Transmission / reception method of wireless alarm system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal line by providing a transmission circuit and a reception circuit in both a management device such as a gas meter and an abnormality detector such as a gas leak alarm, and performing signal transmission between them by radio. The present invention relates to a method for transmitting and receiving a signal in a wireless alarm system that does not require construction work associated with the installation of a signal.

[0002]

2. Description of the Related Art In this type of wireless alarm system,
In order to reduce power consumption, an intermittent receiving method is used in which the power is intermittently supplied to the receiving circuit at a constant cycle, and a reception standby signal having a pulse width longer than the length of the receiving cycle is provided before the alarm signal. It is publicly known that transmission can be reliably performed.

[0003] However, in this case, since the transmitting and receiving operation is performed only when the output of the alarm device is changed or the alarm signal of the gas meter is transmitted, if a failure occurs in the transmitting and receiving device for some reason and the transmitting and receiving function is lost, There has been a problem that an alarm is not issued even when an alarm is generated, and that a process corresponding to the alarm is not performed.

Japanese Patent Application Laid-Open No. 3-154999 discloses that a dedicated synchronization signal is transmitted and received between a management device and an abnormality detector to synchronize the transmission, and a reception standby signal shorter than a reception cycle is transmitted prior to an alarm signal. A method of continuing to supply power to a receiving circuit for a predetermined time when the reception standby signal is received is disclosed. However, according to this, since the timer values of both the management device and the abnormality detector are shifted with time, it is necessary to resynchronize, and therefore, it is suitable only for a system that performs transmission and reception several tens of times a day. Was.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to periodically confirm whether transmission / reception is reliably performed between a management device and an abnormality detector in a wireless alarm system. An object of the present invention is to make it possible to detect a failure at an early stage, to improve the reliability of an alarm system, and to reduce power consumption by shortening a transmission / reception time for confirmation.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided one of an abnormality detector and a management device for periodically checking transmission and reception between a management device such as a gas meter and an abnormality detector such as a gas leak alarm. The side periodically transmits the identification code and the check code following the reception standby signal, and the other side receives the reception standby signal, enters the reception standby state, receives the identification code and the check code, and confirms the reception. When the code matches a prescribed code, an identification code not accompanied by a reception standby signal is returned to one side.

According to the present invention, in the case of a wireless alarm system in which a receiving circuit is set in a receivable state at a fixed period T ₁ by a synchronization timer, the above-described periodic confirmation operation based on the identification code is used. The receiving operation of both the abnormality detector and the management device can be periodically synchronized. That is, the identification code and the check code are periodically transmitted following the reception standby signal from one side of the abnormality detector or the management device, and the reception code is received after the other side receives the reception standby signal and enters the reception standby state. When the check code is received and the check code is received, if it matches the specified code, the self-synchronization timer is cleared and the identification code is returned to one side. Clears its own synchronization timer.

Further, in the present invention, in order to shorten the time required for the transmission / reception confirmation operation as much as possible, the first period from the abnormality detector or the management device at the time of the first transmission is set to the predetermined period T _1.
After transmitting the identification code and check code following the longer reception standby signal, the other side receives the reception standby signal and enters the reception standby state. When it matches, the intermittent reception at the subsequent fixed period T ₁ is enabled, and thereafter, an identification code and a check code are transmitted following the reception standby signal shorter than the time of the first transmission and the fixed period T ₁ . Synchronously and periodically transmit from one side, the other side receives the identification code and the check code, confirms them, and when they match the prescribed code, the one side transmits an identification code without a reception standby signal. It is also possible to adopt a configuration for replying to.

[0009]

According to the present invention, the identification code and the check code are transmitted and received periodically following the reception standby signal, and the signal for checking is transmitted instead of the content of the alarm. To make sure that the code was sent and received, check that the code was sent and received
It can be performed periodically and reliably without being confused with the alarm system of another adjacent house.

[0010]

Next, an embodiment in which the present invention is applied to a wireless gas leak alarm system will be described in detail with reference to the drawings.

FIG. 1 shows a configuration of a gas leak alarm device which is an abnormality detector. The gas leak alarm 10 includes a transceiver 1
1 is connected. The transmitter / receiver 11 includes a microcomputer 12 for judging and coding an output change of the gas leak alarm device 10, a transmission circuit 14 for modulating a signal from the microcomputer 12 and radiating the signal from the antenna 13 as a radio signal, Receiving circuit 1 for demodulating a signal received by antenna 13 and outputting it to microcomputer 12
5 and a power supply control circuit 16 for supplying a DC power supply voltage to the transmission circuit 14 and the reception circuit 15 in response to a control signal from the microcomputer 12.

FIG. 2 shows the configuration of the gas meter which is the management device. The transceiver 18 is also connected to the gas meter 17. The transceiver 18 does not have a microcomputer because the microcomputer 19 is built in the gas meter 17, but the other components are the same as those of the transceiver 11 on the gas leak alarm device 10 side, that is, the microcomputer built in the gas meter 17. A transmission circuit 21 for modulating the signal from the antenna 19 and radiating the signal from the antenna 20 as a radio signal;
A receiving circuit 22 for demodulating a signal received by the antenna 20 and outputting the demodulated signal to the microcomputer 19; and a transmitting circuit 21 in response to a control signal from the microcomputer 19
And a power supply control circuit 23 for supplying a DC power supply voltage to the receiving circuit 22.

When the gas leak alarm 10 is of a microcomputer built-in type, the gas leak alarm 1
The transceiver 12 on the 0 side does not require the microcomputer 12 either.

In the two transmitters / receivers 11, 18, the power supply voltage is not supplied to the transmission circuits 14 and 21 from the power supply control circuit 16.23 only during transmission. . Further, the receiving circuit 15 and 22 are each moreover short duration constant period T ₁ the synchronization timer of the microcomputer 12 within 19 (e.g., 5
Power control circuit 16.23 intermittently (5 ms every second)
The power supply voltage is supplied from the power supply. That is,
Receiving circuit 15, 22 is intermittently received state at a predetermined cycle T ₁ by synchronous timer.

Next, the operation will be described. After the gas meter 17 is set for the wireless alarm device and the gas leak alarm device 10 is installed and the power is turned on, the gas leak alarm device 10 and the gas meter 17 operate normally after a certain period of time has passed. An initial check operation is performed to confirm that the operation is performed. FIG. 3 shows a timing chart of the initial check operation.

The microcomputer 12 outputs a signal for supplying a power supply voltage to the transmission circuit 14 to the power supply control circuit 16 after a lapse of a predetermined time after the power of the gas leak alarm 10 is turned on. Thereby, the transmission circuit 1
4 is supplied with a power supply voltage.

Thereafter, the microcomputer 12 sends a reception standby signal having a pulse width t ₁ equal to or longer than the length T ₁ of the reception cycle to the transmission circuit 14 as shown in FIG.
Subsequently, a check signal is transmitted after a short time. The check signal includes an identification code stored in the ROM of the microcomputer 12 and a content code for confirming the first operation of transmission / reception, that is, a check code, and these codes are continuously transmitted. When the transmission is completed, the supply of the power supply voltage to the transmission circuit 14 is stopped, and the power supply voltage is supplied to the reception circuit 15. The reception standby signal and the check signal transmitted to the transmission circuit 14 are, for example, FM-modulated and radiated from the antenna 13 as radio signals.

The same identification code is stored in the microcomputer 12 on the gas leak alarm device 10 side and the microcomputer 19 on the gas meter 17 side. Determine whether the signal is a check signal from a device that is
It does not respond to the check signals of other neighboring houses.

On the other hand, in the transmitter / receiver 18 on the gas meter 17 side, the receiving circuit 22 is intermittently supplied with the power supply voltage at a constant period T ₁ by the operation of the synchronization timer in the microcomputer 19 and is in a receivable state. If there is a signal input from the antenna 20 within a short time, a demodulated signal is sent to the microcomputer 19 in the gas meter 17.
When it is determined that the demodulated signal is the reception standby signal, the microcomputer 19 sends a signal to the power supply control circuit 23 to extend the supply of the power supply voltage to the reception circuit 22 until the reception of the check signal is completed.

When the receiving circuit 22 receives the check signal following the reception standby signal as shown in FIG. 3B, the microcomputer 19 determines that the transmitted identification code matches its own identification code. Then, if they match, it is confirmed whether or not the subsequently transmitted code is a check code. And the microcomputer 1
In the step 9, when it is determined that the identification code and the check code are other than the predetermined regular code, the code is ignored and the receiving circuit 22 is returned to the original intermittent receiving state via the power supply control circuit 23. Let it. On the other hand, if the code is a legitimate code, supply of the power supply voltage to the transmission circuit 21 is started, an identification code is transmitted as a reception confirmation signal as shown in (3) of FIG. Is stopped to return to the original intermittent power supply state. At this time, the synchronization timer in the microcomputer 19 is cleared, and the synchronization operation is started again.

The transmitted identification code, which is the received acknowledgment signal, is received by the receiving circuit 15 via the antenna 13 in the transmitter / receiver 11 on the gas leak alarm device 10 side as shown in FIG. Becoming a microcomputer 12
Sent to If the received identification code coincides with its own unique identification code, the microcomputer 12 determines that the check signal transmitted by itself is normally received by the gas meter 17 side, The power supply is returned to the intermittent state, and the synchronization timer in the microcomputer 12 is cleared to clear the gas meter 17.
Synchronize with the synchronization timer on the side.

If the identification code, which is the reception confirmation signal, is not returned within the set time, the microcomputer 12 determines that the transmission has not been performed correctly, and
While the supply of the power supply voltage to 5 is stopped, the power supply voltage is supplied to the transmission circuit 14, and a check signal including an identification code and a check code is transmitted again after the reception standby signal. Here, if the identification code of the acknowledgment is not returned again, the same transmission is repeated up to the set repetition number of transmissions.
It is determined that there is an abnormality in 1 or 18, and an alarm is issued by a warning sound or blinking of an LED.

After the initial check is completed and the normal operation is confirmed as described above, the gas leak alarm 10 enters the gas leak detection mode. When the gas leak is detected, an identification code and an alarm content code are transmitted from the gas leak alarm 10 to the gas meter 17 following the reception standby signal for alarm, and the gas leak is detected without gas leak detection.
After a lapse of time, a check signal is transmitted following the reception standby signal, as shown in FIG.

At the time of this periodic check (the same applies at the time of an alarm)
Pulse width t ₂ of the reception standby signal is shorter than the pulse width t ₁ during the initial check, for example, is set to 1 second, t than an integral multiple timer value is receivable period T ₁ of the synchronization timer ₂ / When the value becomes 2, that is, a value smaller by 0.5 seconds, an identification code and a check code for period check are transmitted following the reception standby signal. This takes into account that the values of both the gas leak alarm 10 and the synchronization timers of the microcomputers 12 and 19 of the gas meter 17 shift with the passage of time. This is to enable the reception standby signal to be received.

The reception standby signal and the check signal periodically transmitted from the gas leak alarm 10 are received by the reception circuit 22 of the gas meter 17 by the above operation as shown in FIG. The microcomputer 19 of the gas meter 17 collates the transmitted identification code with its own identification code, and if they match, confirms whether the subsequently transmitted code is a check code. Then, if the identification code and the check code are regular codes defined in advance, the microcomputer 19 starts supplying the power supply voltage to the transmission circuit 21 and, as shown in (3) of FIG. After transmitting the identification code, the power supply to the transmission circuit 21 is stopped, the intermittent power supply state is restored, and at the same time, the synchronization timer in the microcomputer 19 is cleared, and the synchronization operation is started again.

The transmitted identification code, which is a reception acknowledgment signal, is transmitted to the receiving circuit 1 via the antenna 13 in the transmitter / receiver 11 of the gas leak alarm 10 as in the case of the initial check.
5 is received as shown in (4) of FIG. 4 and is sent to the microcomputer 12 as a demodulated signal. If the received identification code coincides with its own unique identification code, the microcomputer 12 determines that the check signal transmitted by itself is normally received by the gas meter 17 side, The power supply is returned to the intermittent state, and the synchronization timer in the microcomputer 12 is cleared to synchronize with the synchronization timer on the gas meter 17 side.

If the identification code, which is the reception confirmation signal, is not returned within the set time, it is determined that the transmission was not performed correctly, and the supply of the power supply voltage to the receiving circuit 15 is stopped. Then, a check signal consisting of an identification code and a check code is transmitted again after the reception standby signal. Here, when the identification code of the reception confirmation is not returned again, the same transmission is repeated up to the set repetition number of times of transmission, and if there is still no response, it is determined that the transceiver 11 or 18 has an abnormality, and a warning is issued. An alarm is issued by sound or blinking LED.

On the gas meter 17 side, if the transceivers 11 and 18 do not operate normally for more than the 24-hour check period, the abnormality is displayed, and if the telemeter function is set, C is displayed. Through the NCU,
An alarm is transmitted to a centralized monitoring center via a telephone line.

Thereafter, a check is performed in a similar manner at regular intervals. Each time, the synchronization timer of the microcomputers 12 and 19 is cleared in both the gas leak alarm 10 and the gas meter 17, and the synchronization is updated. Done.

By using the transmission / reception of the acknowledgment signal of the periodic check, the synchronization timers on the transmission side and the reception side are synchronized, and transmission / reception is performed at the same reception timing, thereby shortening the transmission / reception time of the reception standby signal. Thus, power consumption can be reduced.

It should be noted that the synchronization timer can be cleared at another time, such as when an alarm signal or a check signal is transmitted or received, when the reception confirmation signal is not transmitted.

In the above, the case where a signal is transmitted from the gas leak alarm 10 to the gas meter 17 has been described as an example. Conversely, when a signal is transmitted from the gas meter 17 to the gas leak alarm 10, transmission and reception can be similarly performed. . In addition, the transmitter / receiver 11.1
Although an example is shown in which 8 is connected to the outside of each of the gas leak alarm 10 and the gas meter 17, it may be of a built-in type. Further, the present invention is applicable to wireless transmission by infrared rays or the like, and similarly to other wireless security systems other than the gas leak alarm system.

[0033]

According to the present invention, the following effects can be obtained. Even when it is not necessary to send and receive alarm signals, check signals and their confirmation signals are transmitted and received at regular intervals, so that failures in the transceiver can be detected early, and necessary processing can be performed without generating an alarm when an alarm occurs. It is possible to eliminate the problem that the alarm is not performed and improve the reliability of the alarm system.

An identification code and a check code are periodically transmitted and received following the reception standby signal, and a signal for checking is transmitted instead of transmitting the contents of an alarm.
In order to confirm whether or not the own identification code has been transmitted / received, it is possible to reliably confirm whether the transmission / reception is performed periodically and without being mixed with the alarm system of another adjacent house.

According to the second aspect, the transmission and reception of the acknowledgment signal of the periodic check is used to synchronize the synchronization timers on the transmission side and the reception side, so that transmission and reception can be performed at the same reception timing. The transmission and reception time of the standby signal can be shortened to reduce power consumption.

According to the third aspect, after the installation of the management device and the abnormality detector device, it is possible to perform an initial check whether transmission and reception are normally performed between the management device and the abnormality detector device, and thereafter to perform a periodic check, and furthermore, to perform a periodic check. In this case, since the transmission / reception time of the reception standby signal is shorter than that at the time of the initial check, the periodic check can be performed with less power consumption.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a gas leak alarm device side of a wireless gas leak alarm system to which the present invention is applied.

FIG. 2 is a block diagram showing a configuration on a gas meter side.

FIG. 3 is a timing chart showing an initial check operation.

FIG. 4 is a timing chart showing a periodic check operation.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 gas leak alarm device 11 transceiver 12 microcomputer 13 antenna 14 transmission circuit 15 reception circuit 16 power supply voltage control circuit 17 gas meter 18 transceiver 19 microcomputer 20 antenna 21 transmission circuit 22 reception circuit 23 power supply voltage control circuit

Claims (3)

(57) [Claims] 1. A wireless alarm system including a transmission circuit and a reception circuit in both a management device such as a gas meter and an abnormality detector such as a gas leak alarm device, and receives a signal from one side of the abnormality detector or the management device. Following the standby signal, the identification code and the check code are periodically transmitted, and the other side receives the reception standby signal, enters the reception standby state, receives the identification code and the check code, and confirms the reception. A transmission / reception method for a wireless alarm system, characterized in that when the code matches, an identification code without a reception standby signal is returned to one side. 2. A management circuit such as a gas meter and an abnormality detector such as a gas leak alarm are both provided with a transmission circuit, a reception circuit, and a synchronization timer, and the synchronization timer causes the reception circuit to perform a predetermined period T _1. In a wireless alarm system that is set to be in a receivable state, from one side of the abnormality detector or the management device, an identification code and a check code are periodically transmitted following a reception standby signal, and the reception standby signal is transmitted on the other side. After receiving and setting the reception standby state, receive the identification code and the check code and confirm them, and when they match the prescribed code, clear the self-synchronization timer and return the identification code to one side, A transmission / reception method for a wireless alarm system, wherein one side receives the identification code and, when the identification code coincides with its own identification code, clears its own synchronization timer. 3. A provided with both the transmitting and receiving circuits of the abnormality detector, such as a management device and a gas leak alarms, such gas meters, wireless to intermittently receive state the receiving circuit at a predetermined period T ₁ in alarm system, from one side of the anomaly detector or management device, in the first transmission, following a long reception standby signal from the constant cycle T ₁ transmits the identification code and the check code, the reception standby signal on the other side received after a reception standby state by receiving the identification code and the check code performs the confirmation, when consistent with the provisions of the code, to allow the intermittent reception at the subsequent predetermined period T _1, then , an identification code and check code following the short reception wait signal from the time the initial transmission, the constant period T ₁ in synchronization with the transmitted periodically from the one side, the identification code and checks on the other side Perform the confirmation by receiving over de, when consistent with the provisions of the code, characterized in that it returns the identification code with no reception waiting signal to the one side, method of transmitting and receiving wireless alarm system.