JP5520354B2 - Fire alarm system - Google Patents

Description

  The present invention relates to a fire alarm system in which a plurality of fire alarm devices transmit and receive radio signals using radio waves as a medium.

In recent years, since the obligation to install fire alarms in houses has become legal, a fire alarm system that links a plurality of fire alarms using radio signals is desired from the viewpoint of workability in existing houses. Such a fire alarm system has a function in which a plurality of fire alarms installed in many places sense a fire and sound a warning sound, and if any fire alarm senses a fire, By transmitting information (fire detection information) that informs fire detection to other fire alarms by radio signal, the fire alarm sounds the alarm sound, and not only the fire source fire alarm but also multiple fires An alarm device can be linked to sound an alarm sound all at once, so that the occurrence of a fire can be notified quickly and reliably (see, for example, Patent Document 1). Such a fire alarm is driven by a battery as a power source in order to take advantage of the characteristic of transmitting fire detection information by radio signal, and is usually in a place where maintenance (battery replacement) is difficult such as indoor ceilings. Since it is installed, it is desirable that it can be used without maintenance for a long period of time such as several years. Therefore, in the conventional example described in Patent Document 1, power consumption is reduced by intermittently operating the radio signal receiving means included in each fire alarm device at intervals of several seconds. Has been done. Furthermore, power consumption can be reduced by intermittently operating a fire detection means for detecting a fire. In addition, in order to prevent false alarms in the technical field of fire alarms, for example, when detecting the concentration of smoke generated with a fire, the smoke concentration exceeded a predetermined threshold value several times in succession. Only when it is determined that a fire has occurred (see, for example, Patent Document 2).

JP 2008-4033 A Japanese Patent Laid-Open No. 9-120492

  However, when the receiving means is intermittently driven to extend the battery life as described above, in addition to the time difference from the start of fire to the time when the fire is detected by the fire detecting means, a fire alarm device other than the fire source Because there is a time lag until the fire detection information is transmitted to the fire alarms, it takes a time (for example, several tens of seconds) that cannot be ignored until multiple fire alarms notify the fire alarm. There was a risk of it.

  The present invention has been made in view of the above circumstances, and shortens the time until a plurality of fire alarms interlock to notify a fire alarm while reducing false alarms in which a fire alarm is erroneously notified. With the goal.

The fire alarm system of the present invention includes a plurality of fire alarms, and transmits a radio signal using radio waves as a medium between the plurality of fire alarms. Fire detecting means for detecting, alarm means for informing a fire alarm, transmitting means for transmitting a wireless signal, receiving means for receiving a wireless signal, and a fire alarm to the alarm means when a fire is detected by the fire detecting means A radio signal that transmits a radio signal including a fire alarm message for notifying the other fire alarm device and notifying a fire alarm from the transmitting means, and intermittently starting the receiving means and transmitted from the other fire alarm device And when the fire alarm message is received, the alarm means notifies the fire alarm and a battery for supplying power, and the fire sensing means changes with the fire. Based on the reasoning, the probability of fire occurrence is judged step by step, and when it is judged that the probability is greater than or equal to the first probability, a fire preliminary signal is output and at least a second probability higher than the first probability A fire confirmation signal is output when it is determined that the physical quantity exceeds a predetermined threshold, and it is determined that the probability of fire occurrence is equal to or greater than a first probability, and the physical quantity is When the period continuously exceeding the threshold is equal to or greater than a predetermined determination period, it is determined that the probability of fire occurrence is equal to or greater than the second probability, and the control means outputs a fire preliminary signal from the fire detection means. When is transmitted from the transmitting unit a radio signal including an activation message for activating the receiving means of another fire alarm, and the start and receives a radio signal transmitted from another fire alarm by the receiving means Message After taking only activates receiving means always, characterized in that to transmit a radio signal including a fire alarm message from the transmitting means when the fire determination signal from the fire sensing means is output.

  In this fire alarm system, the control means causes the transmission means to transmit a radio signal including a response message when an activation message is received from another fire alarm, and the fire detection means includes a radio signal including the activation message. It is preferable not to determine whether or not the probability of fire occurrence is greater than or equal to the second probability until the response message is received from all other fire alarms after the transmission.

  In this fire alarm system, the fire detection means fires until the standby time required for the receiving means in all other fire alarms to be always in operation by the startup message after the fire preliminary signal is output. It is preferable not to determine whether or not the probability of occurrence is greater than or equal to the second probability.

  In this fire alarm system, the fire detection means outputs a second fire confirmation signal when it is determined that the probability of the occurrence of a fire is greater than or equal to a third probability equal to the second probability, and the control means Preferably, when the second fire confirmation signal is output from the means, the alarm means is notified of the fire alarm without causing the transmitting means to transmit a radio signal including a fire alarm message.

  The fire alarm system of the present invention has an effect that it is possible to shorten the time until a plurality of fire alarms work together to notify a fire alarm while reducing false alarms that erroneously notify a fire alarm.

1 shows an embodiment of the present invention, where (a) is a block diagram of a fire alarm device, and (b) is a block diagram of a fire detector. It is a time chart for operation | movement description same as the above.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The fire alarm system of the present embodiment is configured by a plurality of fire alarm devices TR having the same function. In the following description, when the individual fire alarms TR are indicated individually, they are indicated as fire alarms TR1, TR2,..., TRn, and when collectively indicated, they are indicated as fire alarms TR.

  As shown in FIG. 1A, the fire alarm device TR transmits a radio signal using radio waves as a medium from the antenna 3 and receives a radio signal transmitted from another fire alarm device TR by the antenna 3. And an alarm unit 5 for notifying (sounding from the speaker) a fire alarm (hereinafter referred to as “alarm sound”) by sound (buzzer sound, voice message, etc.), and fire detection unit 4 having a microcomputer as a main component. A control unit 1 for causing the alarm unit 5 to sound an alarm sound when a signal is detected and transmitting a radio signal including a fire alarm message for notifying other fire alarm devices TR of a fire alarm from the radio transmission / reception unit 2; And a battery power supply unit 6 for supplying operation power to each unit using a battery such as a dry battery as a power source. A unique identification code is assigned to each fire alarm device TR1, TR2,..., And the transmission destination of the radio signal and the fire alarm devices TR1, TR2,.

  The radio transmission / reception unit 2 transmits / receives a radio signal using radio waves as a medium in accordance with “radio station of low power security system” defined in Article 6, Paragraph 4, Item 3 of the Radio Law Enforcement Regulations. In addition, the fire detection unit 4 in the present embodiment detects a fire by detecting the smoke concentration in the physical quantity generated with the fire. As shown in FIG. 1B, the fire detection unit 4 is reflected by a light emitting unit 40 that irradiates light into a space where smoke generated by a fire is introduced, and smoke particles present in the space. A light receiving unit 41 that receives reflected light, and a sensor control unit 42 that controls the light emitting unit 40 to irradiate light intermittently and determine the probability of fire occurrence based on the amount of light received by the light receiving unit 41. Yes. The light emitting unit 40 includes a light emitting diode (not shown) and a drive circuit for causing the light emitting diode to emit light. The light receiving unit 41 includes a light receiving element (not shown) (such as a phototransistor, a photodiode, or a solar cell) and a current / voltage conversion circuit that converts a current signal output from the light receiving element in accordance with the amount of light received into a voltage signal. The The sensor control unit 42 determines the probability of fire occurrence step by step based on the output signal level (voltage level) of the light receiving unit 41 according to the amount of received light, that is, the smoke density in the space, and the probability is the first. A fire preliminary signal is output when it is determined that the probability is equal to or higher than the first probability, and a fire confirmation signal is output when it is determined that the second probability is higher than the first probability.

  For example, when the smoke density (output signal level of the light receiving unit 41) exceeds a predetermined threshold value, it is determined that the probability of fire occurrence is equal to or higher than the first probability, and the smoke density continues above the threshold value. The sensor control unit 42 determines that the probability of the occurrence of a fire is equal to or greater than the second probability when the period exceeding the predetermined period (for example, ten or more seconds) is exceeded. Alternatively, when the smoke concentration exceeds the threshold value, it is determined that the probability of the occurrence of a fire is equal to or higher than the first probability, and the smoke concentration exceeds the threshold value within a predetermined period (for example, ten or more seconds). The sensor control unit 42 determines that the probability of the occurrence of a fire is equal to or greater than the second probability when the ratio or number of times exceeds the ratio or number of times that the smoke concentration has not exceeded the threshold within the period. Also good. Alternatively, when the smoke concentration exceeds the first threshold value, it is determined that the probability of fire occurrence has become equal to or higher than the first probability, and the second condition is higher than the first threshold value. When the threshold value is exceeded, the sensor control unit 42 may determine that the probability of fire occurrence has become equal to or greater than the second probability. Here, in order to reduce power consumption and extend battery life, the sensor control unit 42 operates the light emitting unit 40 and the light receiving unit 41 intermittently at intervals of several seconds (for example, 10 seconds), and the smoke density is increased. When the threshold value or the first threshold value is exceeded, the interval is shortened (for example, every 3 seconds). In addition, in this embodiment, although the case where the fire detection part 4 detects smoke density | concentration as a physical quantity which generate | occur | produces with a fire is illustrated, it is not the main point limited to this, For example, another thing generate | occur | produced with a fire Heat or the like may be detected as a physical quantity.

  The control unit 1 realizes various functions to be described later by executing a program stored in the memory with a microcomputer. When a fire confirmation signal is output from the fire detection unit 4, the control unit 1 drives a buzzer included in the alarm unit 5 to sound an alarm sound, or an alarm voice message (previously stored in a memory or the like ( For example, in order to notify the fire alarm by causing the speaker to sound “fire”, etc., and to notify the fire alarm also in other fire alarm devices TR, a wireless signal including a fire alarm message is transmitted from the wireless transmission / reception unit 2. Send it. Also, when the wireless transmission / reception unit 2 receives a wireless signal transmitted from another fire alarm device TR, the control unit 1 controls the alarm unit 5 to sound an alarm sound.

  In addition, the control unit 1 repeatedly counts a predetermined intermittent reception interval with a timer built in the microcomputer, and activates the radio transmission / reception unit 2 every time the intermittent reception interval is counted, and generates a desired radio wave (other fire alarm TR It is checked whether or not the wireless signal transmitted by the wireless communication device can be received. If the radio wave is not captured, the wireless transmission / reception unit 2 is immediately stopped to shift to the standby state, thereby greatly reducing the average power consumption. The radio wave reception check is performed based on the received signal strength indication signal (Receiving Signal Strength Indication: RSSI signal) output from the wireless transmission / reception unit 2 and is a DC voltage signal proportional to the magnitude of the received signal strength. The details are well known in the art and will be omitted.

  Here, in the radio equipment regulation Article 49-17 “Radio equipment of radio stations of the low power security system” of the Radio Law Enforcement Regulation, the period during which radio signals may be continuously transmitted (transmission period) is 3 seconds or less. It is stipulated that the period (pause period) provided between the transmission period and the transmission period in which the radio signal should not be transmitted is 2 seconds or more (see No. 5 of the same article). For this reason, in the control unit 1 in the present embodiment, the wireless signal is transmitted during the transmission period that complies with the wireless facility rules, and the transmission is stopped and received during the suspension period.

  Therefore, the timing at which a radio signal including a fire alarm message is transmitted from one of the fire alarm devices TR must coincide with the timing at which the wireless transceiver 2 in another fire alarm device TR is ready to receive. For example, the other fire alarm device TR cannot receive the radio signal including the fire alarm message, and all the fire alarm devices TR notify the fire alarm in conjunction (hereinafter referred to as “fire interlock”). ) May take longer.

  Therefore, in this embodiment, when a fire preliminary signal is output from the fire detection unit 4, the control unit 1 causes the wireless transmission / reception unit 2 to transmit a radio signal including an activation message instead of a fire alarm message, and receives the activation message. In the control unit 1 of the other fire alarm device TR, the alarm signal is not emitted from the alarm unit 5 and the wireless transmission / reception unit 2 is in a state where it can be always received. When the fire confirmation signal is output from the fire detection unit 4 in the fire alarm device TR that is the transmission source of the activation message, the control unit 1 of the fire alarm device TR causes the alarm unit 5 to sound an alarm sound. And a wireless signal including a fire warning message is transmitted from the wireless transmission / reception unit 2. At this time, in the other fire alarm devices TR, the wireless transmission / reception unit 2 is ready to receive the wireless signal (a wireless signal including the activation message) transmitted earlier, so the wireless signal transmitted afterwards (fire Wireless signals including alarm messages) can be received immediately, and the control unit 1 of the other fire alarm device TR that has received the fire alarm message sounds an alarm sound from the alarm unit 5 to notify the fire alarm until the fire interlock Time can be shortened.

  For example, as shown in FIG. 2, when a fire preliminary signal is output from the fire detection unit 4 in the fire alarm device TR1, the control unit 1 that has received the fire preliminary signal transmits a wireless signal including an activation message to the wireless transmission / reception unit 2 To send from. In other fire alarm devices TR2, TR3,..., TRn, when the control unit 1 intermittently activates the wireless transmission / reception unit 2 to receive the wireless signal, the activation message is received. After transmitting a wireless signal including a response message (ACK) to be confirmed from the wireless transmission / reception unit 2 to the fire alarm device TR1 as a transmission source, the wireless transmission / reception unit 2 is set in a state in which it can be always received. When a fire confirmation signal is output from the fire detection unit 4 in the fire alarm TR1, the control unit 1 that has received the fire confirmation signal sounds an alarm sound from the alarm unit 5 and also includes a radio signal including a fire alarm message. Is transmitted from the wireless transmission / reception unit 2. In the other fire alarm devices TR2, TR3,..., TRn, the wireless transmission / reception unit 2 in a receivable state receives the wireless signal, and the control unit 1 issues an alarm according to the fire alarm message received by the wireless signal. An alarm sound is generated from the unit 5.

  As described above, according to the present embodiment, it is possible to reduce false alarms in which a fire alarm is erroneously notified by the fire detection unit 4 judging the probability of fire occurrence step by step, and the probability of fire occurrence. Since a wireless signal including an activation message is transmitted at a low stage and the wireless transmission / reception unit 2 of the other fire alarm device TR is in a state in which reception is possible at all times, a fire alarm message is included when the probability of fire occurrence increases When the wireless signal is transmitted, the other fire alarm device TR can immediately receive the wireless signal, and the time until the fire alarm device notifies the fire alarm can be shortened.

  Here, in the sensor control unit 42 of the fire detection unit 4, until the control unit 1 receives a response message for the activation message from all the other fire alarm devices TR, or wirelessly of all other fire alarm devices TR by the activation message. If it is decided not to determine whether or not the probability of fire occurrence is greater than or equal to the second probability until the standby time required for the transmission / reception unit 2 to be always in the reception state elapses, all fire alarms TR It is possible to reduce false alarms associated with fire while shortening the time until the fire is linked. However, in the sensor control unit 42 of the fire detection unit 4, when the control unit 1 has not received a response message to the activation message from all other fire alarms TR, or when the standby time has not elapsed. However, when it is determined that the probability of fire occurrence is equal to or greater than the third probability equal to the second probability, the control unit 1 that outputs the second fire confirmation signal and receives the second fire confirmation signal is the wireless transmission / reception unit. An alarm sound may be generated from the alarm unit 5 without transmitting a radio signal including a fire alarm message from 2. That is, in the fire alarm device TR of the fire source, by not delaying the timing at which the sensor control unit 42 of the fire detection unit 4 determines whether to output the fire confirmation signal (second fire confirmation signal), a large number of While reducing misreporting of fire alarms by the fire alarm device TR, the fire alarm device TR of the fire source can quickly notify the fire alarm to prevent the misreporting.

TR Fire alarm 1 Control unit (control means)
2 Wireless transceiver (transmitting means, receiving means)
4 Fire detection part (fire detection means)
5 Alarm section (alarm means)
6 Battery power unit 40 Light emitting unit 41 Light receiving unit 42 Sensor control unit

Claims (4)

A fire alarm system comprising a plurality of fire alarms and transmitting a radio signal using radio waves as a medium between the plurality of fire alarms,
Each fire alarm detects a fire with a fire detecting means for detecting a fire, an alarm means for notifying a fire alarm, a transmitting means for transmitting a wireless signal, a receiving means for receiving a wireless signal, and a fire detecting means. Sometimes the alarm means is notified of the fire alarm and the other fire alarm device is notified of the fire alarm by sending a radio signal including a fire alarm message from the transmitting means, and the receiving means is intermittently activated to cause another fire. A control means for notifying the alarm means of a fire alarm when receiving the fire alarm message by receiving a radio signal transmitted from an alarm device, and a battery for power supply,
The fire detection means determines the probability of fire occurrence step by step based on the physical quantity that changes with the fire, and outputs a fire preliminary signal when it is determined that the probability is greater than or equal to the first probability. A fire confirmation signal is output when it is determined that the second probability is higher than the second probability, and the probability of fire occurrence is a first probability when the physical quantity exceeds a predetermined threshold value. Determining that the physical quantity exceeds the threshold continuously, and determining that the probability of fire occurrence is greater than or equal to a second probability when the period of time in which the physical quantity continuously exceeds the threshold is equal to or greater than a predetermined determination period;
Control means, a radio signal including an activation message for a fire preliminary signal is output from the fire sensing means activates the receiving means of another fire alarm is transmitted from the transmitting unit, the other fire alarm by the receiving means and After receiving the start-up message after receiving the radio signal transmitted from the device, the reception means is always operated, and when the fire confirmation signal is output from the fire detection means, the radio signal including the fire alarm message is transmitted from the transmission means. A fire alarm system characterized by transmitting. The control means causes the transmission means to transmit a radio signal including a response message when an activation message is received from another fire alarm,
The fire detection means determines whether or not the probability of occurrence of a fire is equal to or higher than the second probability until the control means receives a response message from all other fire alarms after transmitting a wireless signal including an activation message. The fire alarm system according to claim 1, wherein no judgment is made . The fire detection means has a second probability of fire until a standby time elapses until the receiving means in all other fire alarms is always in operation by the activation message after outputting the fire preliminary signal. The fire alarm system according to claim 1, wherein it is not determined whether or not the probability is equal to or greater than the probability . The fire detection means outputs a second fire confirmation signal when it is determined that the probability of fire occurrence is equal to or greater than a third probability equal to the second probability,
The control means, when the second fire confirmation signal is output from the fire detection means, causes the alarm means to notify the fire alarm without transmitting the radio signal including the fire alarm message to the transmission means. The fire alarm system according to 2 or 3 .

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