JP6944557B2 - Alarm system alarm notification method - Google Patents

Description

In the present invention, an alarm device that detects an abnormality such as a fire and gives an alarm is divided into a plurality of groups, an interlocking alarm is given by an alarm device in the same group, and an alarm device between different groups is also interlocked via a repeater. The present invention relates to an alarm notification method of an alarm system that issues an alarm.

Conventionally, alarms that detect and warn fires in houses and the like have become widespread. Of these, residential fire alarms are called residential alarms. For example, such a resident fire alarm operates on a battery power source, and has a sensor unit for detecting a fire and an alarm unit for warning a fire in the resident fire alarm, and fires based on the detection signal of the sensor unit. When a fire alarm is detected, a fire alarm sound is output from the alarm unit, and unlike the so-called automatic fire alarm system, fire monitoring and alarm notification can be performed by the Smoke Detector alone without the need for a receiver, etc., so installation is easy. It is also inexpensive and has become widespread due to the mandatory installation in ordinary houses.

In addition, when a fire alarm sound is output by any of the smoke detectors by performing mutual wireless communication between multiple smoke detectors, the other smoke detectors also work together to output a fire alarm sound. An alarm system using a type of smoke detector has also been put into practical use and has become widespread.

In such an interlocking alarm system, when a fire is detected by the Smoke Detector, the interlocking Smoke Detector that detected the fire is a fire such as "Woo Woo Fire Alarm has been activated. Please check." The alarm sound is output and the alarm display LED is turned on. On the other hand, the interlocking alarm device outputs a fire alarm sound such as "Woo, another fire alarm has been activated. Please check." The LED is blinking.

However, in such a conventional wireless interlocking warning system, when a certain smoke detector receives a radio signal from another smoke detector, a plurality of radio signals using the same communication frequency are simultaneously transmitted. It may arrive and cause a signal collision, and the frequency of signal collisions increases as the number of smoke detectors installed in the warning area increases, which limits the number of smoke detectors that can be installed in one warning area. NS.

In order to solve this problem, the applicant of the present application sets the maximum number of alarms restricted so as not to increase the frequency of signal collision when forming a group consisting of a plurality of alarms, and forms in this way. We have proposed an alarm system in which repeaters are arranged and interlocked between a plurality of groups, and the communication frequencies used for each group are different (Patent Document 3).

In this group-linked warning system, the total number of alarms linked can be increased by linking multiple groups within the warning area, and different groups have different alarm communication frequencies, so a certain group. Even if a signal from an alarm device in the group concerned and a signal from an alarm device in another group arrive at the alarm device at the same time, signal collision does not occur and the signal can be reliably transmitted and received.

The problem of this signal collision is the same in a system that does not distinguish between the master unit and the slave unit of the alarm when using a wireless signal, and in a parent-child system in which a plurality of slave units are arranged with respect to the master unit. In the case of, for example, the master unit sequentially calls and processes the slave units using the individual IDs of the slave units, but when the number of slave units increases, it takes time for the entire communication due to the increase in the number of retries due to the signal collision. It takes. Therefore, in order to reduce the frequency of signal collisions with the master unit, the slave units are limited to a predetermined maximum number or less to form a group, and the master units of each group are interlocked with each other by providing a relay function. It is an alarm system with different communication frequencies used for.

For this reason, the warning system, which is larger than a general house and consists of ordinary wirelessly interlocking residential alarms, cannot cover the entire area due to the limitation of the maximum number of alarms, but the floor area is not obliged to install a fire alarm system. By installing an alarm system that links groups in facilities less than 3,000 square meters, such as group homes that support household affairs for the elderly and people with intellectual disabilities, alarms for the entire group home can be avoided while avoiding the problem of signal collision. The number of interlocking devices has been increased to a sufficient number, and it is possible to provide a fire monitoring function that is substantially equivalent to installing a fire alarm system at low cost.

JP-A-2007-094719 Japanese Unexamined Patent Publication No. 2009-14236 Japanese Unexamined Patent Publication No. 2011-034373

By the way, in such a conventional warning system that performs group interlocking, when a fire alarm detects a fire and gives an alarm, the smoke detectors in the same group and the smoke detectors placed in all other groups Although it is possible to output a fire alarm from, depending on the form of the facility such as a group home where the alarm system is installed, it may be inappropriate to link the alarm devices of all groups.

For example, in a facility where one-story houses with multiple room allocations are connected by a corridor, a group is formed in the house, a smoke detector is installed in each room of each house, and the houses (different groups). The interlocking destination is located far away from the interlocking source group (house: the warning area of the group) to which the dwelling guard (interlocking former dwelling guard) of the room where the fire broke out belongs. Fire alarms were also output to the group's smoke detectors all at once, and despite the fact that the risk of fire was relatively low and there was time to evacuate, the result was to encourage urgent action, and many people evacuated. There is a risk of flooding the road and causing unnecessary confusion, and in the case of non-fire alarms or false alarms, the inconvenience will increase.

In such a case, for example, when the smoke from cooking or the steam in the bathroom activates the residential alarm, the resident of the residence where the alarm that detects the fire is installed can report the non-fire alarm by himself. It is conceivable that a false alarm can be determined, and the cause of operation can be removed, the alarm stop operation of the residential alarm, or the recovery operation can be performed.

Similarly, in the case of a facility divided into multiple floors, groups are usually formed for each floor and linked, but if a fire breaks out on a certain floor, all the groups divided for each floor will live. Fire alarms are output all at once from the police, which may also cause unnecessary confusion and inconvenience.

To solve such problems, for example, in the case of the above-mentioned one-story building, the group adjacent to the group that detected the fire, and in the case of a facility divided into multiple floors, the floor directly above the fire occurrence floor If a linked alarm is given for a group, it will be an appropriate initial alarm according to the degree of fire risk.

However, the resident of the room of the group that does not give the other interlocking alarms only by the interlocking alarm of the group that detects the fire and the group adjacent to it, the fire is occurring in the facility where they live. If the fire spreads to an adjacent group without knowing it, the interlocking warning will make the fire known for the first time, and the evacuation action may be delayed as a result.

The present invention expands the number of interlocking alarms such as residential alarms by group interlocking, and in the alarm notification method of an alarm system that monitors abnormalities in a plurality of warning areas, evacuation behavior is performed according to the occurrence of an abnormality such as a fire. The purpose is to propose and realize a notification form of an abnormality alarm that enables appropriate coping actions including.

(Alarm notification method of alarm system)
In the present invention, a plurality of groups consisting of a plurality of alarms arranged in a warning area are provided, and interlocking alarms are issued by communicating with each other by the alarms in each group, and interlocking alarms are also performed between alarms of different groups. It is an alarm notification method of the alarm system.
When an abnormality is detected by the alarm device in the first group (A), the alarm device outputs an abnormality alarm, and another alarm device in the first group (A) outputs an abnormality alarm.
When an abnormality alarm is output in the first group (A), the alarm preparation interlocking is performed by the first repeater (R1) installed between the first group (A) and the second group (B). It is characterized in that a signal is transmitted and an alarm preparation operation is performed by an alarm device in the second group (B).
Specifically, for example, it is set to 3 times.

(Switching to abnormal alarm)
When the output of the abnormality alarm in the first group (A) continues for a predetermined time , the abnormality interlocking signal is transmitted by the first repeater (R1), and the abnormality interlocking signal is transmitted in the second group (B). The predetermined notification by the alarm device is switched to the abnormality alarm. Specifically, the predetermined period is, for example, 10 seconds. Specifically, the predetermined number of times is, for example, three times.

When an abnormal interlocking signal is transmitted by the first repeater (R1), an alarm is given by the second repeater (2) installed between the second group (B) and the third group (C). The preparation interlocking signal is transmitted, and the alarm preparation operation is performed by the alarm device in the third group (C).

(Basic effect)
According to the alarm system of the present invention, fire alarms are output from all alarms in the group (A) to which the alarms that have detected a fire belong, for example, as an abnormality, and with, for example, an adjacent group (B) in an interlocking relationship with the fire alarms. A fire alarm is output from the repeater (R1) arranged between the two, and all alarms in the adjacent group (B) are notified by an alarm preparation operation, and are further adjacent to and interlocked with the adjacent group (B). Since the fire alarm is output from the repeater (R2) placed between the third group (C) and the related third group (C), it is close to the warning area of the group where the fire was detected and has the highest risk of fire. The group's alarm promptly alerts the resident to a quick evacuation action, and the next high-risk group alerts the resident of the possibility of a fire by prompting an alarm preparation action. By outputting a fire alarm from the repeaters (R1, R2) installed in common areas such as corridors, residents and managers who knew the notification to encourage the alarm preparation operation It is possible to check the situation by listening to a fire alarm when asking about the situation outside the room, and by interlocking alarms between groups according to the degree of risk depending on the situation of the fire, it is appropriate for evacuation etc. Enables various fire countermeasures.

(Effect of transition from alarm preparation operation to alarm operation)
When the repeater (R2) that has transmitted the alarm preparation interlocking signal subsequently detects that the predetermined determination condition is satisfied, for example, the repeater (R2) receives the fire interlocking signal a predetermined number of times within a predetermined period from the alarm device of the group that detects the fire. When the judgment condition is satisfied, a fire interlocking signal is sent to the next group (C) to switch the notification by the alarm preparation operation of the alarm to the output of the fire alarm, so that the fire detection is continued. As the risk level increases, the group that issues fire alarms will be expanded to enable step-by-step evacuation actions that correspond to the fire risk level.

(Effect of the next operation of the repeater that received the alarm preparation signal)
The other repeater (R2), which receives the alarm preparation interlocking signal from one of the interlocking repeaters (R1) and outputs a fire alarm, is interlocked when the fire interlocking signal is subsequently received within a predetermined period. Since the alarm preparation interlocking signal is sent to the third group (C) in the above to make the alarm perform the alarm preparation operation, the group that performs the fire preparation operation according to the increase in the degree of danger due to the continuation of fire detection. Will be gradually expanded, and even for groups that are far from the group that detected the fire, it will be possible to notify the possibility of a fire and encourage preparatory actions such as evacuation.

Explanatory drawing showing an embodiment of an alarm system arranged in a one-story facility Explanatory drawing showing the operation when a fire is detected by the group A Smoke Detector A3. Explanatory drawing which shows the operation which expands the interlocking group by determining the reception of the fire interlocking signal a predetermined number of times by the repeater R1 arranged between groups A and B. A block diagram showing an embodiment of a schematic configuration of a smoke detector Block diagram showing an embodiment of a schematic configuration of a repeater Explanatory drawing showing an embodiment of an alarm system arranged in a three-story facility Explanatory drawing showing the operation when a fire is detected by the Smoke Detector A3 of Group A on the 1st floor. Explanatory drawing showing the operation when a fire is detected by the Smoke Detector B3 of Group B on the 2nd floor. Explanatory drawing showing the operation when a fire is detected by the Smoke Detector C3 of Group C on the 3rd floor.

[Overview of alarm system]
FIG. 1 is an explanatory diagram illustrating an embodiment of an alarm system arranged in a one-story facility, and is an example of the case where a residential alarm device, which is an alarm device that detects and warns a fire as an abnormality, is used. (A) shows a plane, and FIG. 1 (B) shows an elevation.

(Composition of interlocking group)
As shown in FIG. 1, in the facility where the alarm system is installed, one-story houses 1a, 1b, 1c are arranged in a U-shape, for example, and the houses 1a to 1c are divided into five living rooms along the corridor 2. ..

The alarm system is installed with houses 1a to 1c as a warning area, of which group A has house 1a as a warning area, group B has house 1b as a warning area, and group C has house 1c as a warning area. Smoke detectors A1 to A5 that form group A are installed in each room, and similarly, smoke detectors B1 to B5 that form group B are installed in each room of group B, and each room of group C is equipped with smoke detectors B1 to B5. Has installed Smoke Detectors C1 to C5 that form Group C, respectively.

The residential alarms A1 to A5, B1 to B5, and C1 to C5 function as alarms, and when a fire is detected, they operate as an alarm for the interlocking source, output a fire alarm indicating the interlocking source, and their own group. A fire interlocking signal including the specified group code is transmitted according to a predetermined communication protocol, and a fire alarm indicating the interlocking destination is interlocked and output from all other alarms in the group that received the fire alarm. In addition, when the fire alarms A1 to A5, B1 to B5, and C1 to C5 receive a fire interlocking signal transmitted by another smoker in the same group, they operate as an alarm of the interlocking destination, if necessary. The fire interlocking signal (or its contents) is relayed and transmitted.

In addition, "relay" or "relay transmission" in this description means transmitting at least a signal indicating a part of the contents of the received interlocking signal based on the reception of a certain signal.

The interlocking source alarm that detected the fire outputs a fire alarm sound such as "Woo Woo fire alarm has been activated, please check" and lights the alarm display LED, while the interlocking destination alarm is For example, a fire alarm sound such as "Woo, another fire alarm has been activated. Please check" is output and the alarm display LED blinks.

Here, the communication protocol of the residential police devices A1 to A5, B1 to B5, and C1 to C5 is STD-30 (low power security) known as a standard for a specific low power radio station in the 400 MHz band in Japan. It conforms to STD-T67 (standard of radio equipment for specified low power radio station telemeter, telecontrol and data transmission) or STD-T67 (standard of radio equipment of system radio station).

The signals transmitted and received by the Smoke Detectors A1 to A5, B1 to B5, C1 to C5 are a source code which is an identifier indicating a source, a group code which is an identifier indicating a group, a control command or a fire, recovery, and alarm stop. In a format that includes a code (event code) indicating the detection result of the above, for example, the serial number of the Smoke Detector is used as the source code. In the following description, the group codes of groups A, B, and C are shown as Ga, Gb, and Gc.

Further, in the standard of a specific low power radio station in the 400 MHz band, four channel frequencies (communication frequencies) in the 400 MHz band can be used. Therefore, different channel frequencies fa, fb, and fc are assigned as the channel frequencies used in the groups A to C.

The repeater R1 is installed at a predetermined position such as a wall surface between Group A and Group B in the corridor 2, and similarly, the repeater R2 is installed at a predetermined position such as a wall surface between Group B and Group C. ..

(Repeater R1 between groups A and B)
When the repeater R1 receives a fire interlocking signal transmitted using the channel frequency fa when a fire is detected by any of the group A's residential guards A1 to A5, the repeater R1 itself gives a fire alarm. Is output, and an alarm preparation interlocking signal instructing the alarm preparation operation by designating the interlocking group B is transmitted to the group B's residential police B1 to B5 using the channel frequency fb. The alarm preparation interlocking signal includes a group code Gb for designating the group B and a command indicating the alarm preparation operation.

Further, when the repeater R1 receives a fire interlocking signal transmitted using the channel frequency fb when a fire is detected by any of the group B smoke detectors B1 to B5, the repeater R1 itself fires. In addition to outputting an alarm, an alarm preparation interlocking signal instructing an alarm preparation operation by designating a group A having an interlocking relationship is transmitted to the Smoke detectors A1 to A5 of the group A using the channel frequency fa. The alarm preparation interlocking signal includes a group code Ga for designating the group A and a command indicating the alarm preparation operation.

(Smoke alarm preparation operation)
When the Smoke Detectors B1 to B5 of Group B receive the alarm preparation interlocking signal transmitted from the repeater R1 using the channel frequency fb, they perform a predetermined alarm preparation operation and set the channel frequency fb as necessary. Use to relay this. The alarm preparation operation of the Smoke Detectors B1 to B5 is to notify by an alarm sound and / or an alarm display different from the fire alarm, and for example, the following notification is performed.
(1) A short alarm sound such as "beep" is repeatedly output.
(2) Turn on, blink or blink the alarm LED without making an alarm sound.
(3) Perform (1) and (2) above.

The notification by the alarm preparation operation of the alarm notifies the resident that a fire has been detected in a place in the facility away from the living room, and if the fire continues, a fire alarm will be output soon. , Intended to encourage preparations for that.

The function of transmitting the alarm preparation interlocking signal of the repeater R1 can be canceled by a setting operation or the like when it is necessary to output a fire alarm from a plurality of groups of residential alarms all at once. When the alarm preparation interlocking signal transmission function is canceled, the repeater R1 converts the fire interlocking signal of the communication frequency fa including the group code Ga received from the group A into the fire interlocking signal including the group code Gb and the channel frequency fb. To send to Group B Smoke Detector.

Similarly, when a fire interlocking signal having a channel frequency fb is received from the group B, it is converted into a fire interlocking signal including the group code Ga and transmitted to the Smoke detector of the group A using the channel frequency fa.

The repeater R2 arranged between the groups B and C receives the alarm preparation interlocking signal transmitted by the repeater R1 directly or via the residential police B1 to B5 (received at the channel frequency fb). Similar to the case where R1 receives the fire interlocking signal from group A, the repeater R2 itself outputs a fire alarm.

However, even if the repeater R2 receives the alarm preparation interlocking signal, the repeater R2 does not transmit the alarm preparation interlocking signal designating the group C and holds it.

When a fire is detected by any of the group A to C residents' guards that make up the alarm system in this way, the interlocking output of the fire alarm is output from the repeaters R1 and R2 installed in the common area such as the corridor 2. It is always done, and it is possible to surely notify the residents and supporters in the common area of the outbreak of a fire and encourage coping actions such as evacuation.

(Transition from alarm preparation operation to alarm operation)
When the repeater R1 that receives the fire interlocking signal from the group A and transmits the alarm preparation interlocking signal to the group B subsequently detects that the predetermined determination condition is satisfied, the repeater R1 transmits the fire interlocking signal that specifies the group B. The channel frequency fb is used for transmission, and the group B residential guards B1 to B5 that receive the transmission switch the notification by the alarm preparation operation to the interlocking output of the fire alarm and output it.

Here, the group A Smoke Detector that has detected a fire repeatedly transmits a fire interlocking signal when the fire continues, and the repeater R1 receives a fire interlocking signal from the group A within a predetermined period. When the fire interlocking signal is continuously received from the group A even after the alarm preparation interlocking signal is transmitted, the establishment of the judgment condition is detected, and the group B is designated as the channel. A fire interlocking signal using the frequency fb is transmitted.

For this reason, the group B smoke detectors B1 to B5 notify by the fire preparation operation when a fire is detected by the group A smoke detector, and the fire detection continues by the group A smoke detector thereafter. Then, it will be switched to the fire alarm notification. Therefore, the range of fire alarms can be gradually expanded on a group basis.

Further, the fire interlocking signal transmitted from the repeater R1 to the group B using the channel frequency fb is also received by the repeater R2 arranged between the groups B and C, and the repeater R2 designates the group C based on this. Then, an alarm preparation interlocking signal is transmitted using the channel frequency fc, and the group C's residential guards C1 to C5 that receive the signal are made to perform the notification by the alarm preparation operation. Therefore, the range in which the alarm preparation operation is performed can be gradually expanded in group units according to the continuation of fire detection.

(Repeat R2 between groups B and C)
The operation of the repeater R2 is the same as the above-described explanation of the repeater R1 by reading the group A as the group B and the group B as the group C in the case of the repeater R1. In this respect, the alarm preparation operation of Group C related to the repeater R2 and the subsequent switching to the fire alarm are the same.

[Operation of alarm system]
FIG. 2 is an explanatory diagram showing an operation when a fire is detected by the Smoke Detector A3 of Group A.

As shown in FIG. 2, for example, if a fire F occurs in a room in which a group A smoke detector A3 is installed, the smoke detector A3 detects the fire through a predetermined fire detection process and indicates the interlocking source. Along with outputting an alarm, a fire interlocking signal indicated by a solid arrow of the channel frequency fa including the group code Ga is transmitted. The fire interlocking signal transmitted by the Smoke Detector A3 is directly received by the Smoke Detector A1, A2, A4, A5, or is received via the relay of another Smoke Detector, and is received by the Smoke Detector A1, A2, A4, A5. Outputs a fire alarm indicating the interlocking destination.

In addition, the fire interlocking signal transmitted by the Smoke Detector A3 also receives the repeater R1 directly or via the Smoke Detectors A1 and A2, whereby the repeater R1 outputs a fire alarm and designates Group B. The alarm preparation interlocking signal of the channel frequency fb indicated by the broken line arrow including the group code Gb is transmitted.

The alarm preparation interlocking signal transmitted by the repeater R1 is received by the smoke detectors B1 to B5 of the group B, whereby the smoke detectors B1 to B5 perform the alarm preparation operation. Further, the alarm preparation interlocking signal transmitted by the repeater R1 is also received by the repeater R2 directly or via the residential police B1 to B5, and the repeater R2 outputs a fire alarm.

FIG. 3 shows an operation in which the repeater R1 arranged between the groups A and B determines that the fire interlocking signal has been continuously received a predetermined number of times after transmitting the alarm preparation interlocking signal, and expands the interlocking group accordingly. It is explanatory drawing.

As shown in FIG. 2, the repeater R1 that received the fire interlocking signal of the channel frequency fa from the Smoke detector of the group A and transmitted the alarm preparation interlocking signal of the channel frequency fb to the group B was subsequently within a predetermined period. Subsequently, the fire interlocking signal from the group A is received, and when the number of receptions reaches a predetermined number, the establishment of the determination condition is detected. Based on this, as shown in FIG. 3, the repeater R1 specifies the group B and transmits a fire interlocking signal of the channel frequency fb, and the residential guards B1 to B5 that have received this transmit the alarm preparation operation up to that point. The group that outputs the fire alarm is expanded from group A to group B by switching from the notification by the above to the output of the fire alarm.

Further, the repeater R2, which has received the fire interlocking signal of the channel frequency fb from the repeater R1, transmits the alarm preparation interlocking signal of the channel frequency fc specified in the group C, and receives the alarm preparation interlocking signal of the group C. C5 notifies by the alarm preparation operation. In this way, the notification by the alarm preparation operation shifts and expands from the group B to the group C.

A channel frequency (for example, fd) dedicated to the repeater may be provided. In this case, the repeater R1 uses the channel frequencies fa and fb to communicate with the Smoke Detectors of groups A and B, respectively, and uses the channel frequency fd to communicate with the other repeater R2. The repeater R2 may use the channel frequencies fb and fc to communicate with the smoke detectors of the groups B and C, respectively, and use the channel frequency fd to communicate with the other repeater R1.

[Smoke detector configuration]
FIG. 4 is a block diagram showing an outline of the functional configuration of the main part of the Smoke Detector A1, and the same applies to the other Smoke Detectors A2 to A4, B1 to B5, and C1 to C5.

In FIG. 4, the Smoke Detector A1 includes a control unit 10, a communication unit 14 to which the antenna 16 is connected, a sensor unit 12, a notification unit 18, and an operation unit 20, and is operated by a battery power source (not shown).

The control unit 10 is a function realized by, for example, executing a program. As hardware, a computer circuit having a CPU, memory, various input / output ports, etc. is used.

The sensor unit 12 is, for example, a temperature detection unit or a smoke detection unit. When a temperature detection unit is provided as the sensor unit 16, for example, a thermistor is used as the temperature detection element, and in this case, a voltage detection signal corresponding to a change in the resistance value due to temperature is output to the control unit 10. When the smoke detection unit is provided as the sensor unit 16, it has a known scattered light type smoke detection structure, and the light emitting unit using the infrared LED is intermittently driven to emit light at a predetermined cycle according to the instruction of the control unit 10. Synchronized with the light emission, the light receiving part such as a photodiode receives the scattered light scattered by the smoke particles, and the light receiving signal obtained is amplified by the amplifier circuit and output to the control unit 10 as the smoke concentration detection signal. do.

The communication unit 14 transmits and receives interlocking signals (including the above-mentioned alarm preparation interlocking signal and fire interlocking signal) associated with fire monitoring to and from the other Smoke Detectors A2 to A4 according to a predetermined wireless communication protocol, and is necessary. It will be relayed accordingly. In the case of Japan, the communication protocol conforms to the standard of a specific low power radio station in the 400 MHz band, for example, the transmission power is 1 mW or less, and in the case of 1 mW, the line-of-sight communication distance is about 100 meters.

The notification unit 18 includes a speaker, a display LED, and their respective drive circuits, and outputs an alarm sound from the speaker according to an instruction from the control unit 10 as needed, and displays an alarm by the display LED. The operation unit 20 includes an alarm stop switch that receives an operation for stopping the alarm sound and / or the alarm display.

The control unit 10 performs the following fire alarm control, fire recovery control, alarm stop control, and the like.

(Fire alarm control)
The control unit 10 reads the temperature or smoke concentration detection signal output from the sensor unit 12 by AD conversion, detects a fire when the threshold value is equal to or higher than a predetermined threshold value (fire detection processing), and the notification unit 18 indicates the interlocking source. Controls to output an alarm.

When the control unit 10 detects a fire, the control unit 10 generates a fire interlocking signal including the group code Ga, instructs the communication unit 14, and uses the channel frequency fa to the other Smoke detectors A2 to A4. Is controlled, and a fire alarm indicating the interlocking destination is output from the other Smoke Detectors A2 to A4 that have detected the effective reception of the fire interlocking signal.

Here, in the Smoke detectors B1 to B5, the control unit 10 uses the channel frequency fb including the group code Gb, and the Smoke detectors C1 to C5 transmit a fire interlocking signal using the channel frequency fc including the group code Gc. It will be controlled to make it.

Further, when the control unit 10 detects the effective reception of the fire interlocking signal of the channel frequency fa transmitted by any of the other Smoke detectors A2 to A4 or the repeater R1 via the communication unit 14, the notification unit 18 sends the fire interlocking signal. Controls to output a fire alarm that indicates the interlocking destination.

Further, when the control unit 10 detects the effective reception of the fire interlocking signal or the alarm preparation interlocking signal of the channel frequency fa transmitted by any of the other residential guards A2 to A4 or the repeater R1 via the communication unit 14. , The communication unit 14 is instructed to perform control to relay and transmit the received interlocking signal at the channel frequency fa.

The above-mentioned "detection of effective signal reception" means that the group code included in the signal received at the receivable channel frequency matches the group code registered in advance in the memory of the receiving device. It means that it was recognized as a signal addressed to it, and that there was no abnormality in the signal content. Hereinafter, detecting effective reception is simply referred to as "reception".

(Fire recovery control)
The control unit 10 recovers the fire (the fire detection state has been resolved) when the temperature or smoke concentration falls below a predetermined threshold based on the detection signal of the sensor unit 12, for example, when the state continues for a predetermined time or for example, when the state continues for a predetermined number of times. ) Is detected, the fire alarm output indicating the interlocking destination from the notification unit 18 is stopped, a fire recovery interlocking signal is generated, the communication unit 14 is instructed, and the fire recovery interlocking signal is sent to another Smoke Detector A2 to. Control is performed so that the A4 and the repeater R1 transmit at the channel frequency fa, and the other Smoke detectors A2 to A4 and the repeater R1 that receive the control stop the fire alarm output indicating the interlocking destination.

Further, when the control unit 10 receives the fire recovery interlocking signal transmitted by any of the other Smoke detectors A2 to A4 or the repeater R1 via the communication unit 14, the control unit 10 indicates the interlocking destination from the notification unit 18. In addition to controlling to stop the alarm output, it also controls the communication unit 14 to relay and transmit the fire recovery interlocking signal.

(Alarm stop control)
When the control unit 10 detects an alarm stop operation received by the alarm stop switch of the operation unit 20 during the output of the fire alarm as the interlocking source, the control unit 10 stops the fire alarm output indicating the interlocking source from the notification unit 18 and also stops the fire alarm output indicating the interlocking source. The alarm stop interlocking signal is generated, instructed to the communication unit 14, and the control is performed to transmit the alarm stop interlocking signal to the other Smoke detectors A2 to A4 and the repeater R1 at the channel frequency fa, and the other receiving the alarm stop interlocking signal is performed. The fire alarm output indicating the interlocking destination is stopped by the housing guards A2 to A4 and the repeater R1.

Further, when the control unit 10 detects the reception of the alarm stop interlocking signal of the channel frequency fa transmitted by any of the other residential guards A2 to A4 or the repeater R1 via the communication unit 14, the notification unit 18 sends the alarm stop interlocking signal. It controls to stop the fire alarm output indicating the interlocking destination of the above, and also controls to relay and transmit the alarm stop interlocking signal by instructing the communication unit 14.

[Repeat configuration]
FIG. 5 is a block diagram showing an outline of the functional configuration of the main part of the repeater R1, and the same applies to the other repeaters R2 except for the channel frequency handled with the Smoke detector (group) as the communication partner.

In FIG. 5, the repeater R1 includes a relay control unit 22, a first communication unit 24 to which the antenna 26 is connected, a second communication unit 28 to which the antenna 30 is connected, a notification unit 32, and an operation unit 34, and is a battery power source (not shown). Works with.

The repeater R1 implements a function of a setting registration unit (not shown), and the group code of the group to be the communication partner is set and registered in advance. Then, when transmitting and receiving various interlocking signals, the repeater R1 generates an interlocking signal to be transmitted by appropriately referring to the group code registered in the setting, and the effectiveness of the received interlocking signal (a signal to be handled by itself). Whether or not) is checked.

The relay control unit 22 is a function realized by, for example, executing a program. As hardware, a computer circuit having a CPU, memory, various input / output ports, etc. is used.

The first communication unit 24 uses the channel frequency fa, and uses a fire interlocking signal and a fire in accordance with a communication protocol conforming to the standard of a specific low power radio station in the 400 MHz band, for example, with the Smoke Detectors A1 to A5 of Group A. Sends and receives recovery interlocking signals, alarm stop interlocking signals, alarm preparation interlocking signals, etc.

The second communication unit 28 uses the channel frequency fb, and is a standard for a specific low power radio station in the 400 MHz band, for example, between the Smoke detectors B1 to B4 of the group B, as in the case of the first communication unit 24. Sends and receives fire interlocking signals, fire recovery interlocking signals, alarm stop interlocking signals, alarm preparation interlocking signals, etc. according to the communication protocol compliant with.

Here, the channel frequencies handled by the first communication unit 24 and the second communication unit 28 may be switched independently as needed. In this way, the configuration of the repeater R1 can be standardized, and the transmission / reception partner of the interlocking signal can be changed according to the entire system. That is, for example, the configurations of the repeaters R1 and R2 of the present embodiment can be made common, and their respective operations (different groups can be used as communication partners) can be performed.

Further, when a channel frequency fd dedicated to the repeater is provided to communicate with another repeater, a third communication unit (not shown) is provided and the channel frequency fd is used to communicate with the other repeater R2. Similar to the case of the first communication unit 24, for example, a fire interlocking signal, a fire recovery interlocking signal, an alarm stop interlocking signal, an alarm preparation interlocking signal, etc. are transmitted and received according to a communication protocol compliant with the standard of a specific low power radio station in the 400 MHz band. , The repeater R2 to be the communication partner is identified by the source code of the received interlocking signal.

The notification unit 32 includes a speaker, a display LED, and their respective drive circuits, and outputs an alarm sound from the speaker according to an instruction from the relay control unit 22 as needed, and displays an alarm by the LED. The operation unit 34 includes an alarm stop switch that receives an operation for stopping the alarm sound and / or the alarm display.

The relay control unit 22 performs the following fire alarm control, alarm preparation control, alarm preparation release control, fire interlocking switching control, fire recovery control, alarm stop control, and the like.

(Fire alarm control)
When the relay control unit 22 receives the fire interlocking signal of the channel frequency fa transmitted by any of the Smoke detectors A1 to A5 of the group A via the first communication unit 24, the relay control unit 22 indicates the interlocking destination from the notification unit 32. Controls to output a fire alarm.

Further, when the relay control unit 22 receives the fire interlocking signal of the channel frequency fb transmitted by any of the Smoke Detectors B1 to B5 of the group B via the second communication unit 28, the interlocking destination is transmitted from the notification unit 32. Controls to output a fire alarm indicating.

(Alarm preparation control)
When the relay control unit 22 receives the fire interlocking signal of the channel frequency fa transmitted by any of the Smoke detectors A1 to A5 of the group A via the first communication unit 24, the relay control unit 22 is interlocked with alarm preparation including the group code Gb. A signal is generated, instructed to the second communication unit 28, and the alarm preparation interlocking signal is controlled to be transmitted to the Smoke detectors B1 to B5 of the group B using the channel frequency fb, and the alarm preparation interlocking signal is transmitted. Have the received Smoke Detectors B1 to B5 perform a predetermined alarm preparation operation.

Further, when the relay control unit 22 receives the fire interlocking signal of the channel frequency fb transmitted by any of the Smoke Detectors B1 to B5 of the group B via the second communication unit 28, the relay control unit 22 includes an alarm including the group code Ga. A preparation interlocking signal is generated, instructed to the first communication unit 24, and the alarm preparation interlocking signal is controlled to be transmitted to the Smoke detectors A1 to A5 of the group A using the channel frequency fa, and the alarm preparation interlocking is performed. The Smoke Detectors A1 to A5 that have received the signal are made to perform a predetermined alarm preparation operation.

(Alarm preparation release control)
When the relay control unit 22 detects a special operation of the alarm stop switch of the operation unit 34, for example, an alarm preparation release operation received by a long press operation, the relay control unit 22 transmits an alarm preparation interlocking signal. Controls to release.

When the relay control unit 22 receives the fire interlocking signal via the first communication unit 24 or the second communication unit 28 in the state where the alarm preparation control is canceled in this way, the relay control unit 22 specifies the fire interlocking destination group. Is controlled to transmit the fire alarm, and the fire alarm is output all at once from the residential police located in the group that is linked to the group that detected the fire.

(Fire interlocking switching control)
The relay control unit 22 receives the fire interlocking signal from the group A via the first communication unit 24 in a predetermined period after controlling the alarm preparation interlocking signal to be transmitted to the residential police B1 to B5 of the group B. Is counted to determine whether or not the predetermined number of times is reached, and when the arrival at the predetermined number of times is detected, a fire interlocking signal including the group code Gb is generated and instructed to the second communication unit 28 to indicate the fire interlocking signal. Is controlled to be transmitted to the Smoke Detectors B1 to B5 of Group B using the channel frequency fb, and the Smoke Detectors B1 to B5 that have received the fire interlocking signal are output as a fire alarm from the notification by the alarm preparation operation. Switch to operation.

Further, the relay control unit 22 controls the first communication unit 24 to transmit the alarm preparation interlocking signal to the Smoke detectors A1 to A5 of the group A, and then, during a predetermined period, via the second communication unit 28. The number of times the fire interlocking signal is received from the group B is counted to determine whether or not the predetermined number of times is reached. When the arrival at the predetermined number of times is detected, a fire interlocking signal including the group code Ga is generated and the first communication is performed. Unit 24 is instructed to control the transmission of the fire interlocking signal to the group A smoke detectors A1 to A5 using the channel frequency fa, and the smoke detectors A1 to A5 that have received the fire interlocking signal are controlled. Switch from the notification by the alarm preparation operation to the output operation of the fire alarm.

(Fire recovery control)
When the relay control unit 22 receives a fire recovery interlocking signal transmitted by any of the fire guards A1 to A5 that have detected a fire in group A via the first communication unit 24, the relay control unit 22 interlocks with the notification unit 32. While controlling to stop the fire alarm output indicating the above, a fire recovery interlocking signal including the group code Gb is generated, instructed to the second communication unit 28, and the fire recovery interlocking signal is transmitted by using the channel frequency fb. Controls the transmission to the Smoke Detectors B1 to B5 and the Repeater R2 of Group B, stops the notification output or the output of the fire alarm by the alarm preparation operation of the Smoke Detectors B1 to B5 that received the fire interlocking signal, and relays. Stop the fire alarm output on the device R2.

Further, when the relay control unit 22 receives the fire recovery interlocking signal transmitted by any of the Smoke Detectors B1 to B5 that have detected the fire in the group B via the second communication unit 28, the relay control unit 22 sends the fire recovery interlocking signal from the notification unit 32. Along with controlling to stop the fire alarm output indicating the interlocking destination, a fire recovery interlocking signal including the group code Ga is generated, instructed to the first communication unit 24, and the fire recovery interlocking signal is transmitted using the channel frequency fa. Controls the transmission to the Smoke Detectors A1 to A5 of Group A, and stops the notification by the alarm preparation operation of the Smoke Detectors A1 to A5 that received the fire interlocking signal, or the output of the fire alarm.

(Alarm stop control)
When the relay control unit 22 detects an alarm stop operation received via the alarm stop switch of the operation unit 34 during the output of the fire alarm, the relay control unit 22 stops the fire alarm output from the notification unit 32 and sets the group codes Ga and Gb. An alarm stop interlocking signal including each is generated and instructed to each of the first communication unit 24 and the second communication unit 24, and the alarm stop interlocking signal is sent to the group A smoke alarms A1 to A5 and the group B smoke detector B1. ~ B5 and the repeater R2 are controlled to transmit, and the Smoke Detectors A1 to A5 and B1 to B5 and the repeater R2 that have received the control stop the fire alarm output.

Further, when the relay control unit 22 detects the effective reception of the alarm stop interlocking signal transmitted by any of the Smoke Detectors A1 to A5 of the group A via the first communication unit 24, the relay control unit 22 gives a fire alarm from the notification unit 32. While controlling to stop the output, an alarm stop interlocking signal including the group code Gb is generated, instructed to the second communication unit 28, and the alarm stop interlocking signal is sent to the group B's residential police B1 to B5 and the repeater R2. The fire alarm output is stopped by the Smoke Detectors B1 to B5 and the repeater R2 that have received the control.

Further, when the relay control unit 22 detects the effective reception of the alarm stop interlocking signal transmitted by any of the Smoke Detectors B1 to B5 of the group B via the second communication unit 28, the relay control unit 22 gives a fire alarm from the notification unit 32. Control to stop the output, generate an alarm stop interlocking signal including the group code Ga, instruct the first communication unit 24, and transmit the alarm stop interlocking signal to the Smoke detectors A1 to A5 of the group A. And stop the fire alarm output to the Smoke Detectors A1 to A5 that received this.

[Warning system for 3-story facilities]
(Overview of alarm system)
6A and 6B are explanatory views illustrating an embodiment of an alarm system arranged in a three-story facility. FIG. 6A shows an elevation and FIG. 6B shows a plane on the first floor.

As shown in FIG. 6, the facility 3 in which the alarm system is installed is a three-story building on the 1st to 3rd floors, and each floor is divided into five living rooms along the aisle, and these living rooms are connected to the staircase room 4 via the aisle. ing.

In the warning system, facility 3 is installed as a warning area, the first floor is group A, the second floor is group B, the third floor is group C, and the housing guards A1 to A5 are installed in the room of group A, and the room of group B. Smoke detectors B1 to B5 are installed in the room, and smoke detectors C1 to C5 are installed in the living room of Group C. The details of the Smoke Detectors A1 to C5 are the same as those in the embodiment shown in FIG.

A repeater R1 is installed on a predetermined part of the staircase 4, for example, a wall surface of a part located between the first floor and the second floor of the facility (that is, between group A and group B of the warning system), and for example, the facility 2 The repeater R2 is installed on the wall surface of the portion located between the floor and the third floor (that is, between the group B and the group C).

The repeater R1 relays signals transmitted and received between group A and group B, and the repeater R1 relays signals transmitted and received between group A and group B. The details of the repeaters R1 and R2 are the same as those in the embodiment of FIG. 1, and perform fire alarm control, alarm preparation control, alarm preparation release control, fire interlocking switching control, fire recovery control, alarm stop control, and the like.

As the operation of the repeaters R1 and R2 different from the embodiment of FIG. 1, when the fire interlocking signal transmitted from the group on the fire occurrence floor is received, the alarm preparation interlocking signal is not transmitted to the group on the immediately above floor and the fire occurs. The point is that the alarm preparation release control is performed so as to transmit the interlocking signal.

For example, when the repeater R1 receives a fire interlocking signal from any of the group A smoke detectors A1 to A5 on the first floor, the alarm preparation interlocking signal is sent to the group B smoke detectors B1 to B5 immediately above. Since there is a high risk of fire on the floor directly above without transmitting, a fire interlocking signal is transmitted to output a fire alarm.

(Operation of alarm system)
FIG. 7 is an explanatory diagram showing an operation when a fire is detected by the Smoke Detector A3 of Group A. As shown in FIG. 7, for example, if a fire F occurs in a room where a group A smoke detector A3 is installed on the first floor, the fire alarm A3 detects the fire and outputs a fire alarm indicating the interlocking source. At the same time, the fire interlocking signal indicated by the solid line arrow of the frequency fa including the group code Ga is transmitted. The fire interlocking signal transmitted by the resident police A3 is received by the resident police A1, A2, A4, A5 directly or via the relay of another resident police, and a fire alarm indicating the interlocking destination is output.

In addition, the fire interlocking signal transmitted by the housing police A3 is also received by the repeater R1, the repeater R1 outputs a fire alarm, and the repeater receives the fire interlocking signal from the group A located directly below. Since the alarm preparation control is released, the fire interlocking signal including the group code Gb that specifies the group B is generated, and the fire interlocking signal is transmitted using the channel frequency f2 as shown by the broken line arrow.

The fire interlocking signal transmitted by the repeater R1 is received by the group B Smoke Detectors B1 to B5 directly or via a relay, and based on this, the Smoke Detectors B1 to B5 output a fire alarm. The fire interlocking signal transmitted by the repeater R1 is also received by the repeater R2. The repeater R2 is set to cancel the alarm preparation control for receiving the fire interlocking signal from the group B located directly below, but for the fire interlocking signal from the group A on the first floor, which is not the case, the alarm preparation is performed. Control is enabled.

Therefore, when the repeater R2 receives the fire interlocking signal transmitted by the repeater R1, it generates an alarm preparation interlocking signal including the group code Gc that specifies the other group C having an interlocking relationship, and the alarm preparation interlocking signal. Is transmitted using the channel frequency fc, and the reception guards C1 to C4 of the group C on the third floor, which have received the channel frequency fc, perform a notification by an alarm preparation operation.

Judgment condition that the repeater R2 that has transmitted the alarm preparation interlocking signal receives the fire interlocking signal repeatedly transmitted from the fire alarm A3 of the first floor group A that has detected the fire within a predetermined period. When the establishment of is detected, a fire interlocking signal including the group code Gc is generated, the fire interlocking signal is transmitted using the channel frequency fc, and the reception of this is received by the group C Smoke Detector C1 to. C4 switches the notification output from the alarm preparation operation up to that point to the fire alarm output.

FIG. 8 is an explanatory diagram showing an operation when a fire is detected by the Smoke Detector B3 of the 2nd floor group B. In this case, the fire alarm B3 that detects the fire in the group B outputs a fire alarm, and the fire alarm B1, B2, B4, B5 receives the fire interlocking signal from the fire alarm B3 and outputs the fire alarm. do. In addition, the fire interlocking signal from the housing police B3 is also received by the repeaters R1 and R2 to output a fire alarm.

Since the repeater R2 that received the fire interlocking signal has set the release setting for the alarm preparation control for the 3rd floor group C, which is the floor directly above the fire occurrence floor, the fire including the group code Gc that specifies the 3rd floor group C. An interlocking signal is generated and transmitted to the Smoke Detectors C1 to C5, and the Smoke Alarms C1 to C5 that receive the signal also output a fire alarm.

On the other hand, since the Smoke Detectors A1 to A5 of the 1st floor group A are not directly above the fire occurrence floor, the repeater R1 that receives the fire interlocking signal is an alarm including the group code Ga that specifies the group A. A preparation interlocking signal is generated and transmitted to the Smoke Detectors A1 to A5, and the Smoke Detectors A1 to A5 perform notification by an alarm preparation operation.

FIG. 9 is an explanatory diagram showing an operation when a fire is detected by the Smoke Detector C3 of Group C on the 3rd floor. In this case, the fire alarm C3 that detected the fire in Group C outputs a fire alarm, and the fire alarms C1, C2, C4, and C5 receive the fire interlocking signal from the fire alarm C3 and output the fire alarm. do. In addition, the fire interlocking signal from the housing police C3 is also received by the repeaters R1 and R2 to output a fire alarm.

The repeater R2 that has received the fire interlocking signal generates an alarm preparation interlocking signal including the group code Gb that specifies the second floor group B, transmits it to the Smoke Detectors B1 to B5, and receives the Smoke Detectors B1 to B1. B5 outputs a notification by an alarm preparation operation.

Judgment condition that the repeater R2 that has transmitted the alarm preparation interlocking signal subsequently receives the fire interlocking signal repeatedly transmitted from the fire alarm C3 of the third floor group C that has detected the fire within a predetermined period. When the establishment of is detected, a fire interlocking signal including the group code Gb is generated, the fire interlocking signal is transmitted using the channel frequency fb, and the second floor group B Smoke Detectors B1 to B5 that receive this are transmitted. Switches the notification output from the alarm preparation operation up to that point to the fire alarm output.

Further, the repeater R1 that receives the fire interlocking signal transmitted by the repeater R2 generates an alarm preparation interlocking signal including the group code Ga that specifies the first floor group A and transmits it to the Smoke Detectors A1 to A5. The vessels A1 to A5 output a notification by the alarm preparation operation.

[Modification of the present invention]
(Repeater)
In the above embodiment, the group code of the interlocking signal received by the repeaters R1 and R2 is converted into the interlocking destination group code and transmitted, but as another embodiment, the group code is converted by the repeaters R1 and R2. Instead, when the interlocking signal is generated by adding the group code indicating the interlocking destination group to the interlocking signal and transmitted, and the interlocking signal is received by the resident police of the interlocking group, the interlocking is performed. If the group code contained in the signal matches, for example, its own group code, it may be processed as a valid signal.

(Parent-child method)
Further, in the above embodiment, there is no distinction between a master unit and a slave unit, and each alarm device communicates with each other. However, a master unit and a plurality of slave units are provided for each group, and the master unit functions as a repeater. May be provided so that communication for group interlocking alarm is performed between the master units of each group.

Further, the group composed of the master unit and the slave unit and the channel group having no other master unit and the slave unit may communicate with each other via a repeater. At that time, the function of the repeater of the present invention may be added to at least one of the master units.

(Alarm)
Further, in the above embodiment, as an alarm device that detects an abnormality and gives an alarm, a fire alarm that detects a fire and gives an alarm is taken as an example, but a fire alarm other than the smoke alarm and a gas leak alarm device. , CO alarms, alarm systems in which various security alarms are arranged, and systems including these alarms in combination can be similarly applied.

(others)
Further, the above embodiment can be applied not only to residential use but also to alarm devices for various purposes such as buildings and offices.

Further, the above embodiment takes as an example the case where the sensor unit and the alarm output processing unit are integrally provided in the alarm device, but as another embodiment, the alarm device in which the sensor unit and the alarm output processing unit are separated is used. There may be.

Further, the present invention is not limited to the above-described embodiment, includes appropriate modifications that do not impair its purpose and advantages, and is not further limited by the numerical values shown in the above-described embodiment.

A1 to A5, B1 to B5, C1 to C5: Smoke detector R1, R2: Repeater 10: Control unit 12: Sensor unit 14: Communication unit 18, 32: Notification unit 20, 34: Operation unit 22: Relay control unit 24: 1st communication unit 28: 2nd communication unit

Claims (6)

An alarm system alarm that provides multiple groups consisting of multiple alarms placed in the warning area and performs interlocking alarms by communicating with each other with the alarms in each group, and also interlocking alarms between alarms of different groups. It is a notification method
When an abnormality is detected by an alarm device in the first group, the alarm device outputs an abnormality alarm, and another alarm device in the first group outputs an abnormality alarm.
When the abnormality alarm is output in the first group, the alarm preparation interlocking signal is transmitted by the first repeater installed between the first group and the second group, and the first group is concerned. An alarm notification method of an alarm system, characterized in that an alarm preparation operation is performed by an alarm device in two groups.
In the alarm notification method of the alarm system according to claim 1,
When the output of the abnormality alarm in the first group continues for a predetermined time period, the first by sending abnormal interlock signal in the repeater, the alarm in the alarm device in the second group An alarm notification method of an alarm system, characterized in that the preparatory operation is switched to the abnormality alarm.
In the alarm notification method of the alarm system according to claim 2.
When the abnormal interlocking signal is transmitted, the alarm preparation interlocking signal is transmitted by the second repeater installed between the second group and the third group, and an alarm in the third group is transmitted. An alarm notification method of an alarm system, which comprises performing the alarm preparation operation with a device.
In the alarm notification method of the alarm system according to claim 1,
An alarm notification method of an alarm system, characterized in that, as the alarm preparation operation, notification is performed by an alarm sound and / or an alarm display different from the abnormality alarm.
An alarm system alarm that provides multiple groups consisting of multiple alarms placed in the warning area and performs interlocking alarms by communicating with each other with the alarms in each group, and also interlocking alarms between alarms of different groups. It is a notification method
When an abnormality is detected by an alarm device in the first group, the alarm device outputs an abnormality alarm, and another alarm device in the first group outputs an abnormality alarm.
When the abnormality alarm is output in the first group, the alarm preparation interlocking signal is transmitted by the first repeater installed between the first group and the second group, and the alarm preparation interlocking signal is transmitted. Perform alarm preparation operation with alarms in 2 groups,
When the output of the abnormality alarm in the first group continues for a predetermined time period, the first by sending abnormal interlock signal in the repeater, the alarm in the alarm device in the second group An alarm notification method of an alarm system, characterized in that the preparatory operation is switched to the abnormality alarm.
In the alarm notification method of the alarm system according to claim 5.
When the abnormal interlocking signal is transmitted, the alarm preparation interlocking signal is transmitted by the second repeater installed between the second group and the third group, and an alarm in the third group is transmitted. An alarm notification method of an alarm system, which comprises performing the alarm preparation operation with a device.

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