JP2010134623A - Alarm system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alarm system of reducing a processing load of a master device required for periodical transmission, and lowering a consumed current of the master device. <P>SOLUTION: In the alarm system 100 which performs transceiving between the master device 10 and slave devices 11-13, the master device 10 transmits a state signal including state information of the master device 10 or a belonging group thereof, and an own address or a group ID, to the slave devices 11-13, when determined transmission timing comes. Each of the slave devices 11-13 then transmits a state signal including state information of each slave device, and an own address or a group ID, to the master device 10, when determined transmission timing comes in each slave device, and the master device 10 transmits a response signal to the slave devices 11-13, when the state signals are received from all the slave devices 11-13. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an alarm system including a parent alarm device and one or more child alarm devices that can communicate with each other.

  There is an alarm device that detects the heat and smoke generated in the room and gives an alarm. There is an alarm system in which such an alarm device is provided in each room, and one of the plurality of alarm devices functions as a master unit and the other functions as a slave unit to perform an alarm operation in conjunction with each other.

  As a slave unit used in such an alarm system, “a specific low power wireless system configured by one wireless master unit and a plurality of wireless slave units and performing wireless two-way communication with a communicable frequency band as one wave. Communication with the wireless master device is started in a state where all of the wireless slave devices used in the bidirectional communication system are not communicating with the wireless master device. In this case, “communication start” means that the communication is started for any one of the wireless slave units other than the wireless slave unit and the means for transmitting the “communication start” declaration message for declaring the start of communication. ”Means for receiving the declaration message and the received declaration message, and immediately indicate that any one of the wireless slave units other than the wireless slave unit is communicating with the wireless master unit. Means for shifting to a call waiting state; and A means for transmitting a “communication end” declaration message declaring that communication with the wireless master unit has been completed, and any one of the wireless slave units other than the wireless slave unit And a means for receiving a “communication end” declaration message declaring the end of communication, and a means for identifying the received declaration message and immediately canceling the call waiting state ” (For example, refer to Patent Document 1).

Japanese Patent Laying-Open No. 2005-294943 (page 4, FIG. 1)

  In an alarm system comprising a master unit and a slave unit that can communicate with each other, when the slave unit reaches the transmission timing during monitoring, for example, status information regarding the device status of the slave unit such as the remaining battery level and the transmission source Information including the self-address for identification is transmitted as a state signal to the parent device, and the parent device that has received the state signal returns a response signal. This operation is referred to as periodic transmission, and in general, the periodic transmission operation is intermittently performed to grasp whether or not the state of each other is normal.

  However, when the number of slave units constituting the alarm system increases, the frequency of communication between the master unit and the slave units in regular transmission increases. Along with this, the communication tasks to be processed by the parent device increase, and the current consumption of the parent device increases. For example, if the parent device is driven by a battery, the battery life is shortened.

  In addition, if the original function (for example, fire detection or fire alarm) is postponed due to an increase in the amount of processing that the master unit should perform for regular transmission, the function as an alarm device cannot be sufficiently achieved.

  The present invention has been made in order to solve the above-described problems, and provides an alarm system that can reduce the processing load of the master unit required for regular transmission and reduce the current consumption of the master unit. is there.

  The alarm system according to the present invention is an alarm system for transmitting and receiving between a parent alarm device and one or more child alarm devices, wherein the parent alarm device includes at least its own status information in each child alarm device. Each child alarm device that has transmitted the status signal to the parent side transmission timing and received the parent side status signal, sends the child side status signal including its own address and status information to the parent alarm device for each child alarm device. The parent alarm device transmits a response signal to the child alarm device when receiving the child side status signal from all of the child alarm devices. .

In addition, the parent alarm device has received a child-side status signal from another child alarm device a predetermined number of times or more in a state where it has not received a child-side status signal from any of the child alarm devices. In this case, it is determined that a communication abnormality has occurred.
Further, when the child alarm device has not received the parent-side status signal from the parent alarm device and the child-side transmission timing of its own child-side status signal is a predetermined number of times or more, a communication error occurs. It is judged that there is.

  In the alarm system according to the present invention, when the parent alarm device receives the child-side status signals from all the child alarm devices, it transmits a response signal to each child alarm device. Compared to the case where the response signal is returned every time the transmission timing from the device, the number of communication processes can be reduced. Therefore, current consumption required for communication processing can be reduced.

In addition, when the parent alarm device has not received a child-side status signal from any child alarm device of each child alarm device, and has received a child-side status signal from another child alarm device a predetermined number of times or more It is determined that a communication abnormality has occurred. For this reason, a communication abnormality in the alarm system can be detected, and an appropriate response such as inspection can be urged to the user.
Further, when the child alarm device has not received the parent-side status signal from the parent alarm device and the child-side transmission timing of its own child-side status signal is a predetermined number of times or more, a communication error occurs. It is judged that there is. Thereby, communication abnormality can be grasped in the whole system.

Embodiment.
Hereinafter, in the present embodiment, a case where the present invention is applied to an alarm system including a plurality of fire alarm devices that are driven by a battery and perform wireless communication will be described as an example.

FIG. 1 is a diagram showing a configuration of an alarm system 100 according to an embodiment of the present invention. The alarm system 100 includes a plurality of fire alarm devices 10 to 13. Each of these fire alarm devices has a function of detecting a fire and a function of independently alarming. In the present embodiment, the fire alarm functioning as the master unit is “master unit 10”, and the fire alarm functioning as the slave unit is “slave unit 11”, “slave unit 12”, “slave unit 13”. Sometimes referred to separately. The setting of the master unit in each fire alarm is completed by, for example, pressing a registration button (not shown) after turning on the power. On the other hand, the setting of the slave unit in each fire alarm is completed by, for example, pressing a registration button (not shown) after the slave unit is turned on in a state where the registration mode (not shown) of the master unit 10 is pressed to enter the registration mode. In addition, when a matter common to all is described, it is referred to as “fire alarm 10”. Here, the parent device 10 and the child devices 11 to 13 belong to one and the same group.
In FIG. 1, a solid line connecting the parent device 10 and the child devices 11 to 13 indicates that they can communicate with each other by wireless communication.

FIG. 2 is a functional block diagram showing the main configuration of the fire alarm according to the embodiment of the present invention.
In FIG. 2, a fire alarm 10 includes a control circuit 1, a battery 2, a power supply circuit 3, a battery voltage detection circuit 4, a transmission / reception circuit 5, an antenna 6, a fire detection circuit 7, an alarm sound control circuit 8, and an indicator lamp circuit 9. Prepare.

  The battery 2 supplies DC power to the power supply circuit 3. The power supply circuit 3 controls the voltage of the battery 2 to a predetermined voltage and supplies it to the control circuit 1, the transmission / reception circuit 5, the fire detection circuit 7, the alarm sound control circuit 8, and the indicator lamp circuit 9.

  The battery voltage detection circuit 4 detects the voltage of the battery 2 applied to the power supply circuit 3 and outputs a battery voltage detection signal corresponding to the detected voltage to the control circuit 1. When the battery voltage detection circuit 4 detects that the remaining battery level has dropped or exceeds the threshold value for running out of the battery, the control circuit 1 drives the alarm sound control circuit 8 and the indicator lamp circuit 9 and The transmission / reception circuit 5 outputs a state signal including cut state information.

  The fire detection circuit 7 detects a physical change such as smoke or heat based on the fire phenomenon and outputs a signal corresponding to the detected content to the control circuit 1. The alarm sound control circuit 8 is a circuit for controlling the sounding operation by a buzzer / speaker or the like. The indicator lamp circuit 9 is a circuit that controls the lighting operation of indicator lamps such as light emitting diodes.

  The transmission / reception circuit 5 is connected to an antenna 6 for transmitting / receiving a radio signal. The transmission / reception circuit 5 processes the radio signal input from the antenna 6 and performs reception processing in the case of a signal addressed to itself. In the case of other signals, reception processing is not performed. The received signal is output to the control circuit 1. The transmission / reception circuit 5 is controlled by the control circuit 1 to perform transmission processing of a signal such as a status signal.

The control circuit 1 controls the alarm sound control circuit 8 and the indicator lamp circuit 9 on the basis of the signal output from the fire detection circuit 7, and performs an alarm and an alarm stop by the sound and the indicator lamp. Moreover, while performing a required process based on the signal which the transmission / reception circuit 5 received, the transmission / reception circuit 5 is controlled as needed and signals, such as a status signal, are transmitted to another fire alarm.
The storage element 21 is a nonvolatile memory such as an EEPROM, and stores programs executed by the control circuit 1 and various data. In addition, setting data, a self-address, a group ID, and the like relating to the transmission timing of each fire alarm device 10 in the periodic transmission operation described later are also stored.

Next, the operation in the case where a fire occurs in the alarm system 100 having the main unit 10 and the sub units 11, 12, 13 of the fire alarm device configured as described above as one group will be described.
When a fire occurs in the environment in which the base unit 10 is installed, the fire detection circuit 7 detects the fire and issues an alarm by voice or an indicator lamp. Send to. And the subunit | mobile_unit 11-the subunit | mobile_unit 13 which received the interlocking | linkage signal transmitted by the main | base station 10 performs a required alarm by an audio | voice and an indicator lamp. Thereafter, when the base unit 10 no longer detects a fire, the base unit 10 self-recovers and stops the alarm, and stops transmission of the interlock signal to the other handset units 11 to 13. And the other subunit | mobile_unit 11-the subunit | mobile_unit 13 which stopped receiving the interlocking signal also stops an alarm.

In addition, when a fire occurs in the environment where the handset 11 is installed, the handset 11 detects the fire by the fire detection circuit 7 and gives a warning by voice or an indicator light, and information on the fire is used as an interlocking signal. To the slave units 12 and 13. And the main | base station 10 and the subunit | mobile_units 12 and 13 which received the interlocking signal transmitted by the subunit | mobile_unit 11 perform a required alarm by an audio | voice and an indicator lamp.
Furthermore, the master unit 10 that has received the interlock signal issued by the slave unit 11 transfers the interlock signal to the slave units 12 and 13 other than the slave unit 11 that is the transmission source. Accordingly, since the slave units are separated from each other, the slave unit 12 and 13 can receive the interlock signal transferred by the master unit 10 even if the slave unit 11 does not receive the interlock signal of the slave unit 11. . Thereafter, when the slave unit 11 no longer detects a fire, the slave unit 11 recovers itself and stops the alarm, and stops transmission of the interlock signal to the master unit 10 and the slave units 12 and 13. And the main | base station 10 and the subunit | mobile_unit 12 and 13 which stopped receiving the interlocking signal also stop an alarm. As described above, the parent device 10 and the child devices 11 to 13 perform an alarm operation in conjunction with each other, thereby more reliably transmitting an alarm to the user.

Next, the operation of regular transmission during fire monitoring (steady state) between the parent device 10 and the child devices 11 to 13 in the alarm system 100 will be described.
The regular transmission is performed at a predetermined cycle (for example, once every 15 to 20 hours).
When the base unit 10 (for example, the dedicated address 1) reaches a predetermined transmission timing, the state of the base unit 10 or a group to which the base unit 10 belongs and information including a self-address and a group ID for identifying the transmission source are displayed. As a signal, it transmits to the slave unit 11 to the slave unit 13. This status signal may be transmitted repeatedly a predetermined number of times. By doing in this way, the probability of the normal reception by the subunit | mobile_unit 11-the subunit | mobile_unit 13 can be raised.
When the slave unit 11 to the slave unit 13 (for example, addresses 2 to 4) receive the status signal from the master unit 10, at the respective transmission timings, for example, status information regarding the device status such as the remaining battery level, Information including the self address and group ID for identifying the transmission source is transmitted to the parent device 10 as a status signal.
At this time, the master unit 10 and the slave units 11 to 13 can distinguish which fire alarm signal is from the address information included in each status signal.
Examples of the status information of the master unit 10 or the group to which it belongs include the sensor status (degradation, contamination, etc.) of the fire detection circuit 7, the address and group ID of the slave unit in which an abnormality has occurred, and wireless communication. The address and group ID information of the slave unit that does not exist are listed. On the other hand, examples of the status information of the slave unit transmitted from the slave unit to the master unit 10 include the sensor status (deterioration, contamination, etc.) of the fire detection circuit 7, the number of reception processes (the number of processes for radio other than the standard), and the like. Can be mentioned.

During the periodical transmission operation, the slave unit 11 to the slave unit 13 return response signals to the slave unit 11 to the slave unit 13 when the master unit 10 receives the status signals from all the slave units (described later), Alternatively, the status signal is transmitted to the parent device 10 at a predetermined time interval until the status signal is transmitted by the next periodic transmission operation. An upper limit is set for the number of transmissions, and in this embodiment, a case will be described as an example in which the status signal is transmitted a maximum of three times in total. Moreover, the transmission start timing of the status signal by the slave unit 11 to the slave unit 13 and the transmission time interval of the status signal are, for example, the standard status signal transmission timing time according to the serial number set in each fire alarm. On the other hand, addition / subtraction is performed and a predetermined transmission timing is set, so that it differs for each slave unit. By doing in this way, since the timing at which the parent device 10 receives the status signal from each child device can be shifted, the probability of normal reception by the parent device 10 can be increased.
Each slave unit may retransmit the status signal first transmitted to the master unit 10 at predetermined time intervals. In this way, the probability of normal reception by the base unit 10 can be increased even when communication is mixed.

When receiving the status signal from slave unit 11 to slave unit 13, master unit 10 counts the number of receptions of the status signal for each slave unit. If the status signals from all the slave units are received before the number of times the status signal is received from any one of the slave units reaches the maximum value (three times), a response is sent to the slave units 11 to 13. Return the signal.
On the other hand, the master unit 10 communicates with the alarm system 100 when the number of receptions of the status signal from any slave unit reaches the maximum value (three times) before receiving the status signal from all the slave units. It is determined that an abnormality has occurred, and no response signal is returned. In this case, a communication abnormality alarm is transmitted to each slave unit.
Further, for example, when the slave unit 11 does not receive a response signal from the master unit 10 until the slave unit 11 has transmitted the status signal a specified number of times, the slave unit 11 determines that a communication abnormality has occurred.
Furthermore, when the master unit 10 has not received a status signal from each slave unit at the transmission timing of its next periodic transmission operation, it is determined that an abnormality has occurred.

Here, when one of the fire alarms detects a fire, as described above, the fire source fire alarm device outputs an alarm by voice or display, and the control circuit 1 causes the fire alarm of the link destination from the transmission / reception circuit 5. An interlock signal including the address of the fire source fire alarm and status information is transmitted to the firearm. And the fire alarm of the interlocking | linkage destination which received the interlocking signal outputs the interlocking alarm by an audio | voice and a display.
After that, when the alarm stop button of the linked fire alarm device is pressed, the fire alarm devices other than the fire source stop the fire alarm (linked alarm). Also, when the alarm stop button of the fire source fire alarm is pressed, the interlock alarm of the target fire alarm is stopped and only the sound of the fire source alarm is stopped (the indicator light is lit) State). Further, when a fire is detected again after the fire alarm has been restored, the same operation as the first fire detection is performed. On the other hand, when the fire is not detected again, the operation moves to the periodical transmission.

  Next, the periodic transmission operation will be further described with reference to FIGS. 3 to 5 by taking typical operation patterns as an example. 3 to 5 are diagrams showing a flow of regular transmission operations of the parent device 10 and the child devices 11 to 13 in the alarm system 100. FIG.

  In FIG. 3, the base unit 10 starts a periodical transmission operation at a predetermined transmission timing, and all state signals including the state information of the base unit 10 or a group to which the base unit 10 belongs and the self address and group ID are all transmitted. To the slave unit 11 to the slave unit 13 (S21). In response to this, the slave units 11 to 13 transmit a status signal including the status information of each slave unit, the self address and the group ID to the master unit 10 at a predetermined transmission timing. (S22, S23, S24). In the example of FIG. 3, the status signals are transmitted in the order of the slave unit 11, the slave unit 12, and the slave unit 13.

  Master device 10 receives and processes the status signals transmitted from slave device 11 to slave device 13, and counts the number of received status signals for each slave device. When receiving the status signals from all the slave units, the master unit 10 returns response signals to all the slave units (S25). After the response signal is received by each slave unit, the master unit 10 and the slave units 11 to 13 are in a standby state until the transmission timing of the master unit 10 by the next periodic transmission operation. The regular transmission operation is completed by the series of steps up to this point.

  Master unit 10 determines that communication of alarm system 100 is operating normally by receiving the status signals from all the slave units. Moreover, the subunit | mobile_unit 11-the subunit | mobile_unit 13 judges that communication of the alarm system 100 is operating normally by receiving the return of the response signal from the main | base station 10. FIG.

  In the example of FIG. 3, since the slave unit 11 to the slave unit 13 transmit the status signal once each, the base unit 10 returns a response signal. -The subunit | mobile_unit 13 is not transmitting the status signal.

Next, another operation pattern will be described with reference to FIG. In FIG. 4, the case where the subunit | mobile_unit 11 transmits 1 time more than the subunit | mobile_unit 12 and the subunit | mobile_unit 13 is shown.
In FIG. 4, as in the case of FIG. 3, the base unit 10 starts a periodic transmission operation at a predetermined transmission timing, and status information of the base unit 10 or a group to which the base unit 10 belongs, a self-address and a group ID. Are transmitted to all the slave units 11 to 13 (S31). In response to this, the slave units 11 to 13 transmit a status signal including the status information of each slave unit, the self address and the group ID to the master unit 10 at a predetermined transmission timing. However, in the example of FIG. 4, first, the status signals are transmitted in the order of the slave unit 11 and the slave unit 12 in the same manner as in FIG. 3 (S32, S33). Next, when the slave unit 11 reaches a predetermined transmission timing, a status signal is transmitted (S34), and then the slave unit 13 transmits a status signal (S35). That is, for the transmission of the status signal of the master unit 10, the slave unit 11 transmits the second status signal before the slave unit 13 transmits the first status signal.

  The base unit 10 receives and processes the status signals transmitted from the slave units 11 to 13, and counts the number of status signal transmissions for each slave unit each time it is received. In the example of FIG. 4, the number of state signal transmissions of the handset 11 is 2, and the handset 12 and handset 13 are each once. Since the status signal is transmitted from the slave unit 13 (S35), the status signal is transmitted from all the slave units. Therefore, the master unit 10 returns the response signal at this timing. (S36). The regular transmission operation is completed by the series of steps up to this point.

  In the example of FIG. 4, the status signal is transmitted twice by the slave unit 11, but the number of transmissions of the status signal received by the master unit 10 does not reach the maximum value (3 times). Therefore, base unit 10 determines that communication of alarm system 100 is operating normally, and returns a response signal. The slave unit 11 to the slave unit 13 determine that the communication of the alarm system 100 is operating normally by receiving the response signal returned from the master unit 10.

Next, another operation pattern will be described with reference to FIG. FIG. 5 shows a case where some abnormality occurs in communication processing between the slave unit 13 and the master unit 10 and the status signal cannot be transmitted.
In FIG. 5, as in the case of FIG. 3, the base unit 10 starts a periodical transmission operation at a predetermined transmission timing, the status information of the base unit 10 or a group to which the base unit 10 belongs, the self address and the group ID. Are transmitted to all the slave units 11 to 13 (S41). In response to this, the slave units 11 to 13 transmit a status signal including the status information of each slave unit, the self address and the group ID to the master unit 10 at a predetermined transmission timing. However, in the example of FIG. 5, since a communication error has occurred between the master unit 10 and the slave unit 13, the slave unit 11 and the slave unit 12 are in sequence of status signals as in the case of FIG. Transmission is performed (S42, S43). Next, transmission of the status signal is performed at the predetermined transmission timing in the order of the slave unit 11, the slave unit 12, and the slave unit 11 (S44, S45, S46).

  Each time the master unit 10 receives a status signal, it counts the number of status signal transmissions for each slave unit. Here, although the number of status signal transmissions received from the slave unit 11 has reached the maximum value (three times), the master unit 10 has not received the status signal from the slave unit 13 even once. Accordingly, the base unit 10 determines that some kind of communication abnormality has occurred in the alarm system 100, and transmits a communication abnormality alarm related to the handset 13 to the handset 11 and the handset 12 (S47). Thereby, the subunit | mobile_unit 11 and the subunit | mobile_unit 12 can know that communication abnormality generate | occur | produced. When a communication abnormality occurs, an alarm may be given by voice or an indicator lamp together with transmission of a communication abnormality alarm (S47). In this way, it is possible to notify the user that a communication abnormality has occurred and to prompt the necessary response. In addition, since the operation | movement of regular transmission is performed regularly, for example, when the communication abnormality of the main | base station 10 and the subunit | mobile_unit 13 is recovered | restored, you may cancel | release a communication abnormality alarm by operation | movement of subsequent periodic transmission.

  As described above, according to the present embodiment, base unit 10 returns a response signal when status signals are transmitted from all of handset 11 to handset 13. Therefore, compared with the case where a response signal is returned every time a status signal is transmitted from each slave unit, the number of communication processes of the master unit 10 can be reduced to 1/3. This means that the amount of charge consumed in the transmission process is reduced to 1/3, and the life of the battery 2 as a drive source can be extended. Moreover, since the amount of communication traffic can be reduced, communication interference to other communication devices can be reduced. Furthermore, since the transmission processing time of the base unit 10 can be reduced to 1/3, the processing time for performing the original functions such as fire detection and fire alarm can be increased. These effects become more prominent as the number of slave units connected to the master unit increases.

  In addition, the master unit 10 counts the number of transmissions of the status signal from the slave units 11 to 13, and the slave unit that has not yet transmitted the status signal even if the number of transmissions of any of the slave units exceeds a predetermined number. If it exists, it is determined that a communication abnormality has occurred in the alarm system 100, and a communication abnormality alarm is transmitted. For this reason, it is possible to detect a communication abnormality that has occurred in the alarm system 100 and to prompt the user to take appropriate measures such as inspection.

In the present embodiment, an example in which status signals are transmitted between all the slave units 11 to 13 connected to the alarm system 100 and the master unit 10 has been described. However, the number of slave units is large. In some cases, a series of operations for periodic transmission may be performed for each group.
Alternatively, the base unit 10 transmits a status signal transmission request to all the slave units, but the status signal can be transmitted for each group. For example, in an alarm system in which a large number of slave units are connected, the slave units are divided into several groups, and when a status signal is received from all the slave units in each group, A response signal is sent back to. The same process is performed for all groups. Even if it does in this way, while the frequency | count of communication of a main | base station can be reduced, since the subunit | mobile_unit which belongs to a group without a communication abnormality does not need to transmit a status signal, it can also reduce the frequency | count of communication of a subunit | mobile_unit. it can.

Moreover, in this Embodiment, although the main | base station 10 counted the transmission frequency from the subunit | mobile_unit 11-the subunit | mobile_unit 13, it detected the communication abnormality and transmitted the communication abnormality alarm, The transmission of the alarm may be performed by the slave unit.
For example, the slave unit counts the number of transmissions of its own status signal, and a communication error occurs in the alarm system when no response signal is returned from the master unit despite the maximum number of transmissions. Therefore, it is possible to transmit a communication abnormality alarm to the master unit and other slave units.
As another example, when the radio signal input from the antenna is a status signal, the slave unit performs reception processing even if the radio signal is not addressed to itself, and the status signal transmission count of other slave units is set as the slave signal. Count for each machine. When the number of status signal transmissions of any of the slave units exceeds the maximum value, it is determined that a communication abnormality has occurred in the alarm system, and a communication abnormality alarm is transmitted to the master unit and other slave units. be able to.
As described above, the slave unit detects the communication abnormality in the alarm system and transmits the communication abnormality alarm, whereby the processing load on the master unit can be reduced.

  In the above description, the case where the present invention is applied to an alarm system including a fire alarm that is driven by a battery and performs wireless communication has been described as an example, but the power supply method and communication method of the fire alarm are limited. In addition to fire alarms, it can also be applied to alarms for detecting abnormalities.

It is a block diagram of the alarm system which shows embodiment of this invention. It is a functional block diagram of an alarm device showing an embodiment of the present invention. It is a figure which shows the flow of operation | movement of the periodic transmission of an alarm system. It is a figure which shows the flow of other operation | movement of the periodic transmission of an alarm system. It is a figure which shows the flow of other operation | movement of the periodic transmission of an alarm system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Control circuit, 2 Battery, 3 Power supply circuit, 4 Battery voltage detection circuit, 5 Transmission / reception circuit, 6 Antenna, 7 Fire detection circuit, 8 Alarm sound control circuit, 9 Indicator light circuit, 10 Fire alarm (parent machine), 11 Fire alarm (child machine), 12 Fire alarm (child machine), 13 Fire alarm (child machine), 100 Alarm system.

Claims (3)

In an alarm system that transmits and receives between a parent alarm device and one or more child alarm devices,
The parent alarm device transmits a parent-side status signal including at least its own status information to each child alarm device at a parent-side transmission timing,
Each child alarm device that has received the parent-side status signal transmits a child-side status signal including its own address and status information to the parent alarm device at a child-side transmission timing determined for each child alarm device. ,
The parent alarm device transmits a response signal to the child alarm device when receiving the child-side status signal from all the child alarm devices.   When the parent alarm device receives a child side status signal from another child alarm device a predetermined number of times or more without receiving a child side status signal from any of the child alarm devices. The alarm system according to claim 1, wherein it is determined that a communication abnormality has occurred.   If the child alarm device is not receiving the parent-side status signal from the parent alarm device and the child-side transmission timing of its child-side status signal is equal to or greater than a predetermined number of times, a communication abnormality has occurred. The alarm system according to claim 1, wherein the alarm system is determined.

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