JPH0215183Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is an immediate type that sends a fire detection signal to the power supply signal line drawn out from the fire receiving device when the power supply is temporarily cut off in the fire detection state and then turned on again. A fire detector, such as a heat sensor, is connected to a delay-type fire detector, such as a smoke detector, which sends out a fire detection signal after a predetermined period of time has elapsed after the power is turned on again, and the fire signals from each fire sensor are accumulated. The present invention relates to a fire alarm device having a storage function for receiving fire alarms.

In recent years, non-fire alarms from fire alarm devices have become a social issue, and efforts are being made to develop highly reliable fire alarm devices that eliminate false alarms due to non-fire alarms.

Conventional countermeasures against false alarms caused by non-fires include receiving detection signals from fire detectors at a central fire receiving device, and if the detection signal from the fire detector is temporary or sudden, In other words, if the duration of reception of the detection signal is short, the fire is not detected, and the fire is determined only when the detection signal from the fire detector is continuously received for a predetermined period of time, for example, 5 seconds, and the fire is detected. A so-called storage type fire receiving device has been proposed, which has a function of storing detection signals from a fire alarm.

However, if the fire detector connected to such a fire receiving device is a smoke detector that detects smoke, if smoke such as cigarettes flows into the detection chamber of the smoke detector, the smoke from the detection chamber will be detected. Because the structure is designed to prevent leakage, alarm-level smoke often stays in the detection chamber for more than 5 seconds. In this case, the smoke detector will continue to send out detection signals, and the fire reception device will , upon receiving a continuous detection signal for 5 seconds,
There was a problem in which a fire alarm was issued even though there was no fire.

Therefore, in order to avoid receiving temporary or sudden noise, the power supply is temporarily cut off and then turned on again, and the fire detection signal is output again after a predetermined period of time longer than the outflow time required for the outflow of cigarette smoke, etc. A fire receiving device has been proposed that prevents non-fire alarms depending on whether or not they are received. However, as a fire detector connected to the fire receiving device, in addition to a smoke detector, it is also conceivable to connect a heat sensor that detects a temperature rise due to the occurrence of a fire.

By the way, fire detection in a heat sensor is performed by closing a fire detection contact by pressing a rise in temperature due to the occurrence of a fire by the expansion of air in a sensing chamber of the heat sensor, and sending out a fire detection signal. In addition, in response to a slow rise in temperature due to heating or the like, a leak hole is provided in the sensing chamber of the heat sensor to release slowly expanding air to prevent malfunctions in non-fire situations such as heating. Therefore, in such a heat sensor, when a fire detection operation is performed due to the rapid expansion of air in the sensing chamber due to a fire, the expanded air flows out of the sensing chamber through the leak hole, causing the sensing chamber to become damaged. The air pressure decreases, making it difficult to maintain fire detection over a long period of time.

Therefore, if a fire receiving device is set to have a very long time until it can receive a fire detection signal after the power is turned off and then turned on again, it will not be able to continuously receive the fire detection signal from the heat detector. There was a problem in which the fire receiving device failed to report the detection of the fire even though the detector detected the fire.

The present invention was developed in view of the above problems, and includes a smoke detector that detects smoke by detecting smoke caused by a fire, and a heat detector that detects a fire by detecting a temperature rise caused by a fire. Even if both fire detectors are connected to the power signal line,
It is an object of the present invention to provide a fire alarm device having a receiving function that can prevent false alarms from smoke detectors due to non-fire causes and also prevent false alarms from heat detectors or smoke detectors.

In order to achieve this objective, the present invention provides an immediate fire detection signal that immediately sends a fire detection signal to the power supply signal line drawn out from the fire receiving device by temporarily cutting off the power supply in the fire detection state and then turning it on again. a sensor and
In a fire alarm device connected to a delay-type fire detector that transmits a fire detection signal after a predetermined delay time has elapsed since the power supply was temporarily cut off and turned on again in a fire detection state, a cutoff circuit that cuts off the power supply to each fire detector for a predetermined period of time when a fire detection signal from a type fire detector or a delay type fire detector is detected; for a short time,
a first output circuit that generates an output; and an alarm circuit that generates an alarm if a fire detection signal from the immediate fire detector is obtained when the output of the first output circuit occurs;
The fire detector further includes a counter circuit that measures a fire detection signal from the delayed fire detector within a certain period of time after the output from the first output circuit elapses after the cutoff time by the cutoff circuit. When the signal reaches a predetermined number of times within the certain period of time, the alarm circuit issues an alarm.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of the present invention.

First, the configuration will be described. Reference numeral 1 denotes a fire receiving device, and a plurality of smoke detectors 4 and heat detectors 5 are connected in parallel to power signal lines 2 and 3 led out from the fire receiving device 1. The smoke detector 4 detects smoke caused by a fire, and when the detected amount reaches a predetermined level, activates a self-holding element such as an SCR.
A fire detection signal is sent to the fire receiving device 1 by short-circuiting or maintaining low impedance between the signal lines 2 and 3. In addition, when the power supply to the smoke detector 4 is temporarily interrupted while a fire is detected, the fire detection operation is restored by turning off the self-holding element such as the SCR, and when the power is turned on again, the smoke detector Since capacitors are used in the circuit, it takes time for the fire detection function of the smoke detector to become normal, and the fire detection signal is delayed after a predetermined delay time, for example 3 seconds, after the power is turned on again. This is a delay type fire detector that can send out a fire alarm. On the other hand, the heat detector 5 uses the expansion force of the air in the sensing chamber of the heat sensor 5 to close the fire detection contact when the temperature rise due to the occurrence of a fire reaches a preset level or higher. , 3 are short-circuited or set to low impedance, and a fire detection signal is sent to the fire receiving device 1.
In addition, even if the power supply to the heat detector 5 is momentarily cut off in the fire detection state, the fire detection contact closes due to the expansion force of the air in the sensing chamber, and the fire detection operation continues. This is an instant fire detector that sends out a fire detection signal immediately after being turned on. 6 is a relay, which operates when the smoke detector 4 or heat sensor 5 detects a fire and the signal lines 2 and 3 are short-circuited or have low impedance, and relay contacts 6a and 6
Close b. 7 is a delay circuit, and relay 6
It operates when the relay contact 6a is closed, and produces an output after a delay of a predetermined time, for example, 100 msec. From the output terminal of the delay circuit 7, relay contacts 12b and 1
It is connected to the input terminals of the one-shot circuits 8 and 10 via the one-shot circuit 3b, and to the input terminal of the one-shot circuit 9 via the delay circuit 15. One-shot circuits 8, 9, and 10 receive the drive signal, and output the latched one-shot pulses of 1 second, 1.5 seconds, and 60 seconds, respectively. It is equipped with one-shot contacts 8a and 9a that operate only when outputting, and when the one-shot circuit 8 is activated, the one-shot contact 8a opens for one second, thereby supplying power to the relay 6, smoke detector 4, and heat sensor 5. It will be cut off for 1 second. Further, the delay circuit 15 and the one-shot circuit 9 form a first output circuit. The driving time of the one-shot contact 9a of the one-shot circuit 9 (1.5
seconds) is longer than the power cut-off time (1 second) for fire detectors 4 and 5, and the time during which the immediate fire detector cannot normally output a fire signal (e.g. 20 to
By setting the time shorter (30 seconds later), the reception relay 12 is activated by the fire detection signal from the heat detector 5, which is an immediate fire detector, to perform identification reception. Further, the one-shot circuit 10 includes a counter circuit 11 which is a detection contact circuit.
is being reset. The delay circuit 15 delays the drive signal sent from the delay circuit 7 by a predetermined period of time, for example, 100 msec, and outputs it to the one-shot circuit 9, thereby delaying the drive signal from the one-shot circuit 8 during operation.
The one-shot circuit 9 is driven after a delay of 100 msec to prevent the reception relay 12 from malfunctioning due to the first fire signal. One shot circuit 8
The counter circuit 11 connected to the output signal from the one-shot circuit 8 counts the number of one-shot pulses output from the one-shot circuit 8, and when the count reaches a preset arbitrary count, for example, eight. It is equipped with a detection contact 11a that operates when 12 is a relay that identifies and receives the fire detection signal from the heat sensor 5; 13 is a relay that identifies and receives the fire detection signal from the smoke detector 4; the relays 12 and 13 operate the fire reception circuit; is forming. 14 is a recovery switch. 12a,1
3b is a relay contact of the relays 12 and 13, and after the fire detection signal is detected by the relay 12 or 13, the relay contact 12b or 13b is opened, and the delay circuit 7 is connected to the one shot circuit 8, 9, 10 after the fire is detected. Prohibit output.

Next, the operation will be explained. First, the case where the heat sensor 5 detects a fire will be described with reference to the signal waveform diagram in FIG. When a fire is detected and the heat sensor 5 is activated, a short circuit or low impedance occurs between the signal lines 2 and 3, which activates the relay 6 and closes the relay contact 6.
When a is closed, the power supply voltage of the fire receiving device 1 is applied to the delay circuit 7. After being delayed by 100 msec, this applied voltage is used as a drive signal to drive the one-shot circuit 8 and also operates the delay circuit 15 to drive the one-shot circuit 9 with a delay of 100 msec from when the one-shot circuit 8 is driven. Further, when the one-shot contact 8a is opened by driving the one-shot circuit 8, the power supply to the relay 6 and the heat sensor 5 is cut off, and the relay 6 is turned off. When relay 6 is turned off, relay contact 6a opens and drive signals to one-shot circuits 8 and 9 are cut off, but one-shot contacts 8a and 9a of one-shot circuits 8 and 9 continue to operate for a predetermined period of time. When the relay contact 8a is restored after 1 second, power is supplied to the relay 6 and the heat sensor 5. heat detector 5
The fire detection operation continues even in a temporary power cut-off state, and if the signal lines 2 and 3 are short-circuited or have low impedance, the relay 6 is activated while the one-shot contact 9a continues for 1.5 seconds. turns on immediately. When the relay contact 6b of the relay 6 is closed, the reception relay 12 is turned on, and the relay contact 12a is turned on.
The relay 12 is self-maintained, and the operation of other relay contacts of the relay 12 (not shown) indicates that a fire has been detected by the heat sensor or issues a fire alarm. Also, by opening the relay contact 12b of the relay 12, the one-shot circuit 8, 9, 10 after a fire is detected.
The output of the delay circuit 7 is prohibited.

Next, the operation when the smoke detector 4 detects a fire will be explained with reference to the signal waveform diagram in FIG. When a fire is detected and the smoke detector 4 is activated, the signal lines 2 and 3 are short-circuited or have low impedance, which activates the relay 6. When the relay contact 6a closes, the power supply voltage of the fire receiving device 1 is applied to the delay circuit 7. applied. This applied voltage is delayed by 100 msec in the delay circuit 7 and output as a drive signal for driving the one-shot circuits 8 and 10, and further processed in the delay circuit 15.
The one-shot circuit 9 is driven with a delay of 100 msec.
Here, as shown in FIG. 3, when the one shot contact 8a is opened by driving the one shot circuit 8, the power supply to the relay 6 and the smoke detector 4 is cut off, and the relay 6 is turned off. When the relay 6 is turned off, the relay contact 6a opens and the drive signals to the one-shot circuits 8, 9, and 10 are cut off, but the one-shot circuits 8, 9, and 10 each output a predetermined one-shot pulse, and the one-shot Contact 8
a and 9a also continue to operate for a predetermined period of time. When the one-shot contact 8a is restored after one second, power is supplied to the relay 6 and the smoke detector 4, but the smoke detector 4
After the power is turned on again, a certain amount of time is required for the smoke detector to function as the capacitors in the circuit are charged with the power, so the fire detection signal is not sent immediately and the relay 6 remains off. be. In addition, the driving time of the one-shot circuit 9 is set to be shorter than the time it takes for the smoke detector 4 to function, so that the one-shot contact 9a is activated after it operates.
It will recover after 1.5 seconds. When the fire detection function of the smoke detector becomes normal after a predetermined delay time elapses, for example 3 seconds, the smoke detector 4 sends out the fire detection signal again and short-circuits or lowers the impedance between the signal lines 2 and 3. Activate relay 6. The same operation is then repeated multiple times. That is, relay 6
When the relay contact 6a is closed, the one-shot circuit 8 and the one-shot circuit 9 are activated with a delay of 100 msec, and when the one-shot contact 8a of the one-shot circuit 8 is opened, the relay 6 is restored. The one-shot circuits 8 and 9 also repeat the pattern operation in which they recover after a predetermined period of time. The counter circuit 11 is a one-shot circuit 8
The one-shot pulses emitted from the
It is driven at the falling edge of the 8th one shot pulse from the one shot circuit 8 and closes the contact 11a. In this state, when the smoke detector 4 sends out a fire detection signal and the relay 6 operates, power is supplied to the receiving relay 13 through the relay contact 6b and the contact 11a of the counter circuit 11, the receiving relay 13 operates, and the relay contact 13a is closed and self-maintained, and the operation of other relay contacts of the relay 13 (not shown) indicates that the smoke detector 4 has detected a fire or issues a fire alarm. Further, the relay contact 13b of the relay 13 is also opened, and the output of the delay circuit 7 to the one-shot circuits 8, 9, and 10 is prohibited after the fire is detected. This is because the one-shot circuits 8, 9, and 10 do not need to operate after the fire alarm is issued. The one-shot circuit 10 outputs a 60-second one-shot pulse, and the counter circuit 11 is reset at the falling edge of the one-shot pulse, so the smoke detector fires eight times within 60 seconds. If there is no signal, smoke detectors will not indicate a fire. Note that this counter circuit 11 is for preventing malfunction, and the count number can be set arbitrarily.

FIG. 4 is a circuit diagram showing another embodiment of the fire receiving device according to the present invention. The embodiment shown in FIG. 4 is a one-shot circuit 16 that operates for a predetermined period of time (for example, 20 seconds) by activation of a delay type fire detector instead of the counter circuit 11 in the embodiment of FIG.
are connected in parallel to the one-shot circuit 10, and the one-shot normally closed contact 16a and the one-shot normally open contact 10 are connected in parallel.
It is characterized in that the relay 13 is driven through a, and after a predetermined time (20 seconds) determined by the driving time of the one-shot circuit 16 has elapsed, and within the operating time of the one-shot circuit 10, the relay 13 is activated. The system is designed to receive fire detection signals.

The delay circuit 17 prevents the receiving relay 13 from malfunctioning by further delaying the drive signal delayed by 100 msec in the delay circuit 7 and supplying the delayed signal to the one-shot circuits 10 and 16.

Next, the operation will be explained based on the signal waveform diagram shown in FIG. When the relay 6 is activated by the activation of the smoke detector 4, the drive signal delayed by 100 msec by the delay circuit 7 is further delayed by 100 msec through the intervention of the delay circuit 17, and then drives the one-shot circuits 10 and 16. When 20 seconds have elapsed since the one-shot circuits 10 and 16 were activated, the one-shot circuit 16 was restored and the one-shot contact 16a was closed. On the other hand, the one-shot circuit 10 continues to drive, and the one-shot contact 10a
is closed. If the smoke detector 4 operates again within this time, the relay 6 turns on, and the relay contact 6
When b is closed, the relay 13 is turned on, and the operation of the relay contacts (not shown) of the relay 13 displays the detection of a fire from the smoke detector 4 or issues a fire alarm.
In addition, the relay contact 13b of the relay 13 is also in an open state, and the one-shot circuit 8, 9, 10 after the fire is detected.
The output of the delay circuit is prohibited. That is,
It is determined that the smoke detector has detected a fire when relay 6 operates again between 20 and 60 seconds after the power supply voltage is first cut off and then turned on, and the relay is relayed within 20 seconds or more than 60 seconds. Even if 6 operates, it is determined to be a malfunction.

The circuit configuration for receiving the fire detection signal from the immediate type heat sensor is the same as the circuit configuration shown in FIG.

As explained above, the present invention prevents non-fire alarms and prevents heat detectors or smoke detectors from failing even when a heat detector and a smoke detector are connected to the power signal line. can be prevented.
Additionally, it is possible to determine whether a heat detector or a smoke detector is currently activated.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an embodiment of the present invention, Fig. 2 is a signal waveform diagram showing the operation of receiving a fire detection signal from a heat sensor, and Fig. 3 is an embodiment of the invention shown in Fig. 1. FIG. 4 is a circuit diagram showing another embodiment of the present invention, and FIG. 5 is a signal waveform diagram showing the operation of receiving a fire detection signal from a smoke detector in FIG. FIG. 3 is a signal waveform diagram showing the operation of receiving a fire detection signal from the device. 1... Fire receiving device, 2, 3... Power signal line, 4... Smoke detector, 5... Heat sensor, 6... Relay, 7, 15, 17... Delay circuit, 8, 9, 1
0, 16... one shot circuit, 11... counter circuit, 12, 13... receiving relay.

Claims (1)

[Scope of claim for utility model registration] Instant fire detector that immediately sends a fire detection signal to the power signal line drawn out from the fire receiving device by temporarily cutting off the power supply in the fire detection state and then turning it on again. and a delay-type fire detector that transmits a fire detection signal after a predetermined delay time has elapsed since the power supply was temporarily cut off and then turned on again in a fire detection state, the fire receiving device having: a cutoff circuit that cuts off the power supply to each fire detector for a predetermined time when a fire detection signal from the immediate fire detector or the delayed fire detector is detected; and the predetermined delay time from the cutoff by the cutoff circuit. a first output circuit that generates an output for a shorter period of time; an alarm circuit that generates an alarm if a fire detection signal from the immediate fire detector is obtained when the output of the first output circuit occurs; a counter circuit that measures a fire detection signal from the delayed fire detector within a certain period of time after the elapse of the output from the first output circuit after the elapse of the cutoff time by the cutoff circuit; A fire alarm device characterized in that the alarm circuit issues an alarm when a predetermined number of times is reached within a certain period of time.