JPS62109196A - Fire sensor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a storage type fire detection device,
The first fire alarm in response to the activation of fire detectors;
There will be three signals: a second fire alarm corresponding to the activation of two fire detectors, and a third fire alarm corresponding to the activation of three or more fire detectors, together with the identification of fire alarms and non-fire alarms. This system enables alarms, controls, evacuations, etc. to be carried out according to the fire level.

Conventional technology Conventional fire detection devices determine the presence or absence of fire information from the detector only by turning the switching output on or off. Although no fire has occurred due to condensation on the sensor surface or insects entering the sensor,
A temporary non-fire alarm similar to the occurrence of a fire occurs. In order to solve these non-fire alarm problems, storage type fire detection devices have been proposed. A storage type fire detection device is
Set the accumulation time to determine the continuity of the fire detection signal detected by the detector, and if there is a fire detection signal after the accumulation time has elapsed, it will be treated as a fire alarm, and if there is no fire detection signal, it will be treated as a non-fire alarm, increasing the reliability of the information. This is how it was done.

FIG. 6 is a circuit diagram showing a general configuration of a storage type fire detection device. In the figure, l is a DC power supply, 2 is a fire detection circuit, 3 is a disconnection detection circuit, 4 and 5 are signal lines that also serve as power supply lines, 6 is a terminal that terminates signal lines 4 and 5, and 71 to 7n are heat exchangers. Detector, 81 to 8n are smoke detectors, 9 is an accumulation processing circuit,
R is a relay, and R1 is a contact point of relay R. The accumulation processing circuit 9 includes a fire disposal circuit 91 and an accumulation control circuit 92.

FIG. 7 is a time chart diagram illustrating the operation of the storage type fire detection device described above. When the smoke density or heat level reaches the fire level at time t1 as shown in FIG. The current flowing through increases. This circuit current is detected as a fire detection signal by the fire detection circuit 2 and inputted to the accumulation processing circuit 9. Accumulation control circuit 92
Now, relay R is activated by the fire detection signal, and as shown in Fig. 7 (
As shown in c), the accumulation time Ts is set. The accumulation time Ts is set to a value larger than the time required for a temporary fire alarm, such as cigarette smoke that has entered the smoke detectors 81 to 8n, to be naturally exhausted. The storage time Ts is up to 60 according to the standard.
It is defined as seconds.

As described above, when relay R operates, its contact R1
is opened, the signal line 4.5 is opened, and the heat sensors 71 to 7
n, the power supply to the smoke detectors 81 to 8n is cut off, and a first fire alarm PI as shown in FIG. 7(b) is obtained.

Next, when the accumulation time Ts elapses, the relay R falls,
Contact R1 closes. When the contact R1 closes, if any of the heat detectors 71 to 7n or the smoke detectors 81 to 8n is still operating and a fire detection signal is output, as shown in FIG. 7(d). , a fire signal is output from the fire processing circuit 91. The fire disposal circuit 91 is configured to perform a delay operation in which the fire is not disposed of until the response time of the storage control circuit 92 and the activation time of the relay R.

The smoke detectors 81 to 8n generally have a built-in electronic circuit, and require start-up time for the electronic circuit to start up. Therefore, a time delay Tdl occurs from the point t2 when the relay R falls and the contact R1 closes until the smoke detectors 81 to 8n enter normal operation and output the smoke detection signal, and the fire output also occurs at this time. Only time will be delayed. Tdl is a delay time of a fire relay, etc. in the fire processing circuit 91.

The detection signal that becomes the first fire alarm is not caused by a fire,
If it is temporary, the smoke level or heat level will decrease as shown by the dotted line (a) in Figure 7 (a), and after the heat accumulation time Ts has elapsed, there will be no reason to issue a fire alarm. . Therefore, since no sensing signal is output after the accumulation time TS has elapsed, no fire signal is output. This makes it possible to distinguish between non-fire and fire.

Problems to be Solved by the Invention As mentioned above, storage type fire detection devices are susceptible to increases in indoor smoke concentration due to smoking and other causes, dew condensation on the sensor surface due to sudden changes in ambient temperature, and insects entering the sensor. This is effective in that it can eliminate temporary non-fire alarms caused by intrusion, etc.

However, with this conventional fire detection device, there are two situations: a state including a non-fire alarm, such as when only one of the heat detectors 71 to 7n and smoke detectors 81 to 8n is activated, and a state where two or more of the smoke detectors are activated. Since the fire alarm processing is carried out by the same accumulation operation at the actual fire level, it is not possible to provide alarms, control, and evacuation according to the fire level.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention provides a pair of signal lines that also serve as power supply lines, three or more fire detectors connected between the signal lines, a fire detection circuit that detects a fire detection signal from the current flowing through the signal line; and a fire detection circuit that opens the signal line when a fire detection signal is given from the fire detection circuit, and closes the signal line after a predetermined period of time has elapsed to detect a fire. In the fire detection device, the fire detection circuit includes an accumulation processing circuit that sets an accumulation time for determining the continuity of the signal, and generates a fire output if a fire detection signal is present after the accumulation time has elapsed. a first fire detection circuit that detects that one of the fire detectors is activated and inputs the detected result to the storage processing circuit; and a second fire detection circuit that detects that two of the fire detectors are activated and generates a fire output. and a third fire detection circuit that detects that three or more of the fire detectors are activated and generates a fire output.

Operation In the fire detection device according to the present invention, when one of the fire detectors is activated, it is detected by the first fire detection circuit,
The detection signal is input to the accumulation processing circuit. The accumulation processing circuit opens the signal line when the fire detection signal is given from the first fire detection circuit, and closes the signal line after a predetermined time has elapsed to set an accumulation time to determine the continuity of the fire detection signal. do.

Then, if there is a fire detection signal after the accumulation time period has elapsed, a fire output is generated. If the fire detection signal is transient, the fire detection signal disappears after the accumulation time has elapsed, so it is treated as a non-fire alarm and no fire output is generated. This allows identification of non-fire alarms and fire alarms when one of the fire detectors is activated.

Next, when the two fire detectors operate, the second fire detection circuit detects the fire and generates a fire output in a system different from the M product processing circuit. If only one fire detector is activated, there is a possibility that it is a temporary non-fire alarm, but if two fire detectors are activated, the probability of a real fire is extremely high. This will enable early warning in the event of a major fire.

Furthermore, if three fire detectors are activated.

Since this is judged to indicate that the fire level is quite high, this is detected by the third fire detection circuit and, for example, an operation such as issuing an omnipotent level fire warning is performed. Note that this third detection circuit can also be used for line checks and the like.

Therefore, according to the present invention, it is possible to obtain a fire detection device that is capable of distinguishing between fire alarms and non-fire alarms, as well as providing alarms, control, evacuation, etc. according to the fire level, and is suitable for buildings where fire panic is likely to occur.

Embodiment FIG. 1 is an electrical circuit diagram of a fire detection device according to the present invention. In the figure, the same reference numerals as in FIG. 6 indicate the same components.

The fire detection circuit 2 includes a TL flow detection resistor RF inserted and connected in series in a circuit loop surrounding the signal line 4-5, and also includes a first fire detection circuit 21 and a second fire detection circuit 22.
and a third fire detection circuit 23.

The first fire detection circuit 21 is a circuit that detects that one of the heat detectors 71 to 7n and smoke detectors 81 to 8n is activated and inputs it to the accumulation processing circuit 9, and is for current limiting. , a Zener diode ZD+ for determining the threshold level of the fire detection current, and a transistor Q+ for detection amplification.

The second fire detection circuit 22 is a circuit that detects the operation of two fire detectors and generates a second fire output, and includes a current limiting resistor R2 and a threshold level of the fire detection current. It includes a Zener diode ZD2 for determining and a transistor Q2 for detection and amplification. Since the fire detection current that flows when two fire detectors operate is approximately twice that of one-biased operation, the Zener diode Z
The Zener voltage VZ2 of D2 is the Zener diode Z
It is selected to be about twice the Zener voltage vz1 of D+.

The third fire detection circuit 23 is a circuit that detects the activation of three or more fire detectors and generates a third fire output, and similarly to the above fire detection circuits 21 and 22, resistor R3
, a Zener diode ZD3, and a transistor Q3. Since the fire detection current that flows when three or more fire detectors operate is more than three times that in the case of one partial operation, the Zener voltage VZ3 of the Zener diode ZD3
is the zener voltage VZI of the zener diode ZD,
Select three times or more.

RLI is a resistor that adjusts the fire detection current flowing to each of the heat detectors 71 to 7n, and RL2 is a smoke detector 81 to 8n.
A resistor for adjusting the fire detection current flowing through each of the resistors, 10
is a test transmitter that artificially generates a fire condition.

In the above embodiment, when any one of the heat detectors 71 to 7n or the smoke detectors 81 to 8n operates, the fire detection current flowing through the signal line 4.5 at that time causes the resistance RF to
The voltage drop that occurs across the zener voltage VZ1 exceeds the Zener voltage VZ1,
Zener diode ZDI conducts and transistor Q1
The fire detection signal is input from the first fire detection circuit 21 to the storage processing circuit 9 under the amplification effect of the fire detection circuit 21 . In the storage processing circuit 9, when the fire detection signal is given from the fire detection circuit 21 of @1, the signal &! Contact R1 inserted in 4.5
An accumulation time is set in which the circuit is opened and the circuit is closed after a predetermined period of time has elapsed to determine the continuity of the fire detection signal. and,
If there is a fire detection signal after the accumulation time has elapsed, a first fire output is generated.

If the fire detection signal is transient, the fire detection signal disappears after the accumulation time has elapsed, so it is treated as a non-fire alarm and no fire output is generated. by this,
A non-fire alarm or a fire alarm is identified when one of the fire detectors is activated.

Next, if two fire detectors are activated, the resistor RF
The voltage drop occurring across the Zener diode Z of the second fire detection circuit 22 is approximately twice that in the case of one-bias operation.
D2 becomes conductive and receives the amplification effect of transistor Q2,
A second fire output is generated in a system different from the storage processing circuit 9. This will enable early warning in the event of a major fire.

Furthermore, when three or more fire detectors operate, the voltage drop across the resistor RF becomes more than three times that in the case of one unbalanced operation, and the Zener diode ZD3 of the third fire detection circuit 23 becomes conductive, causing the transistor Q3 to become conductive. , a third fire output is generated in a system different from the storage circuit 9. This third fire output is used as a signal for issuing an almighty level fire alarm. The third fire output of the third detection circuit 23 is also used when the transmitter 10 is operated for a line test or the like.

By the way, among the fire detection signals given from the first fire detection circuit 21, when they are caused by the sensing operations of the smoke detectors 81 to 8n, they may include a temporary non-fire alarm. , it is extremely effective to provide the storage processing circuit 9 in that it can eliminate this. However, the heat sensor 71
~7n, there is almost no room for the above-mentioned temporary non-fire alarm to occur. Therefore, when the fire detection signal given from the first fire detection circuit 21 is processed by the accumulation processing circuit 9, whether it is caused by the operation of the heat sensors 71 to 7n or the operation of the smoke detectors 81 to 8n It is desirable to identify the cause of the fire and to generate a fire output as soon as possible if the heat detectors 71 to 7n are operating. FIG. 2 shows a specific example of the storage processing circuit 9 which can carry out the above-described discrimination operation.

In the embodiment shown in FIG. 2, the accumulation time for determining the continuity of the fire detection signal detected by the smoke detectors 81 to 8n is set, and the rise time of the smoke detectors 81 to 8n is determined within the accumulation time. By checking the operation of the heat sensors 71-7n in a short period of time, it is possible to determine the operation of the heat sensors 71-7n and the smoke detectors 81-8n. 91 is a fire processing circuit, 92 is an accumulation control circuit, and 93 is a delay circuit. The delay circuit 93 performs a delay operation to prevent the fire disposal circuit 91 from disposing of the fire by the response time of the storage control circuit 92 and the activation time of the relay R.

The accumulation control circuit 92 includes an oscillator 921 that generates clock pulses, a flip-flop 922, and an analog gate) 923.
, a multi-stage counter 924, a matrix gate circuit 825, and a variable storage time setting circuit 926.

The flip-flop 822 is set by the fire detection signal given from the first fire detection circuit 21, and
It is preset by a preset signal given from matrix gate circuit 325. AND gate 923 performs a logical product of the set signal applied from flip-flop 922 and the clock pulse applied from oscillator 921, and causes counter 824 to perform a counting operation based on the output thereof.

Counter 924 counts the output of AND gate 823 and provides the counted output to matrix gate circuit 924 as a code pulse. The matrix gate circuit 924 controls the relay R according to the count value given from the counter 924.
A time chart is created for setting the accumulation time, checking the operation of the heat sensors 71 to 7n, presetting the flip-flop 922, etc.

The accumulation time variable setting circuit 92B is configured to set the accumulation time variable setting circuit 92B depending on the type of the smoke detectors 81 to 8n, since the time it takes for transient smoke to enter and be naturally discharged differs depending on the type of the smoke detectors 81 to 8n. The storage time can be set variably. In this example, it is configured by a relay contact circuit,
The count value corresponding to the accumulation time is varied depending on the selected relay contact.

For example, as shown in FIG. 3, the smoke detectors 81 to 8n have built-in electronic circuits such as a rectifier circuit 8a, a capacitor 8b, a sensing circuit 8c, and a switching circuit 8d, and have a rise time determined by these circuits. In the smoke detectors 81 to 8n having the circuit configuration shown in FIG. 3, the minimum rise time is about 120 m5, and generally about several seconds.

FIG. 4 is a time chart diagram when the smoke detection signal is a fire alarm.

When the smoke density level reaches the fire level at time t1 as shown in FIG. 4(a), one of the smoke detectors 81 to 8n is activated and a fire detection signal P1 is output (FIG. 4(b)). ), this fire detection signal P1 is detected by the first fire detection circuit 21, inputted to the storage control circuit 92, and the flip-flop 922 is set. flip flop 9
22 is set, the set signal causes the clock pulse CL from the oscillator 821 to be read into the counter 924 through the AND gate 923;
At the same time as the count value of is counted up, the relay R is operated by the signal given from the matrix gate 925, the contact R1 is opened, and the signal line 4.5 is opened. This state continues until the count value m corresponding to the accumulation time Ts (see FIGS. 4(C) and 4(d)). The accumulation time Ts is usually set to about 20 seconds to 40 seconds.

Next, the operation of the heat sensors 71 to 7n is checked within the accumulation time TS set as described above.
As shown in Figures (C) and (d), at t2, the count of the counter 824 that started counting at time t1 has progressed to a count value r smaller than the count value m giving the accumulation time Ts after time TI has elapsed. , the output of the matrix gate circuit 925 causes the relay R to drop only for a time T2.

Close the contact R1 and pass the signal line 4.5 to the heat sensor 71~
7n. The time T2 in this case is selected to be a value sufficiently smaller than the rise time Tdl of the smoke detectors 81 to 8n. For example, if the smoke detectors 81 to 8n are made of electronic circuits as shown in Fig. 3, the minimum rise time is about 120 m5, and normally it is about several seconds, so the operation check time T2 is selected to be about 90 m5. do.

It is desirable to select the time point t2 at which the operation check is performed so that the time T1 calculated from t1 when the counter 824 operates to determine the start of the accumulation time Ts is about 10 seconds.

If the operation check time T2 is selected to the above value, the heat sensors 71 to 7n will be activated by closing the contact point R].
At the same time, even if power is supplied to smoke detectors 81 to 8n, 2
Since the power is cut off before the smoke detectors 81 to 8n turn on, the smoke detectors 81 to 8n cannot respond. On the other hand, since the heat sensors 71 to 7n have a heat sensing structure using bimetal contacts in principle, a sensing signal is output almost simultaneously with the contact operation due to heat sensing. Therefore, the heat sensor 71
Only the operations of ~7n can be checked.

At operation check time T2, if any of the heat sensors 71 to 7n is operating and there is a heat detection signal,
It is treated as a fire alarm and the first fire output is issued. Unlike smoke detectors, in the case of heat detectors, the probability of generating a temporary non-fire alarm is extremely low, so if a heat detector is activated, it is considered a fire alarm, and early detection of a fire is possible. This contributes to

Next, after t3, which is the end of the accumulation time TS, the relay R drops and the contact R1 closes. When the contact R1 closes, if any of the smoke detectors 81 to 8n is operating and a fire alarm based on smoke detection is output, the fire processing circuit 91 is activated as shown in FIG. 4(e). The first fire output is issued.

The time point at which the first fire output is generated is at the end t3 of the accumulation time Ts.
, the rise time Tdl of the smoke detectors 81 to 8n and the operation delay time Td of the fire relay etc. in the fire treatment circuit 91.
This is after 2.

If the smoke detection signal P1 is transient and the heat detectors 71 to 7n are not operating during the operation check time T2, the cause of the fire alarm has disappeared after the accumulation time Ts has elapsed ( (see Fig. 5(a)), no smoke detection signal is output after the elapse of the integration time Ts (see Fig. 5(b) to (d)).
), the first fire output does not occur (see Figure 5(e)).
In this case, at time t4 when the counter 824 has counted up to the count value n, the matrix gate circuit 825 supplies the preset signal Rs to the flip-flop 822 to preset it, and then the counter 924 is cleared.

Effects of the Invention As described above, the present invention provides a storage type fire detection device in which a fire alarm is issued in response to the activation of one fire detector, and a first fire alarm in response to activation of one fire detector. By setting three signals, the second fire alarm corresponds to the activation of fire alarms and the third fire alarm corresponds to the activation of three or more fire detectors, it is possible to distinguish between fire alarms and non-fire alarms, and to determine the fire level. A fire detection device capable of combined alarm, control, evacuation, etc. can be provided.

[Brief explanation of drawings]

Fig. 1 is an electrical circuit diagram of a fire detection device according to the present invention;
The figure is a block diagram of the storage processing circuit, Figure 3 is the electrical circuit diagram of the smoke detector, Figures 4 (L) to (e) and Figures 5 (a) to (
f) is a time chart diagram for explaining the operation of the embodiment of FIGS. 1 and 2, FIG. 6 is an electric circuit diagram of a conventional fire detection device, and FIGS. 7(a) to (d) are the same diagrams. It is a time chart figure. 2 fists...Fire detection circuit 21...First fire detection circuit 22...Second fire detection circuit 23/Third fire detection circuit 4.5Φ/Signal lines 71 to 7n... Heat detectors 81 to 8n...Smoke detector 9...Storage processing circuit 91...Fire processing circuit 92/-11 storage control circuit

Claims (2)

[Claims] (1) A pair of signal lines that also serve as power lines, three or more fire detectors connected between the signal lines, a fire detection circuit that detects a fire detection signal from the current flowing through the signal lines, and a fire detection circuit that detects a fire detection signal from the current flowing through the signal lines. When a fire detection signal is given from the detection circuit, the signal line is opened, and after a predetermined time elapses, the signal line is closed to determine the continuity of the fire detection signal.The accumulation time is set, and the fire detection signal is determined after the accumulation time has elapsed. In a fire detection device comprising an accumulation processing circuit that generates a fire output when a signal is present, the fire detection circuit detects activation of one fire detector and inputs the signal to the accumulation processing circuit. A fire detection circuit 1, a second fire detection circuit that generates a fire output when two fire detectors are activated, and a second fire detection circuit that detects activation of three or more fire detectors and detects a fire. A fire detection device comprising: a third fire detection circuit that generates an output. (2) The fire detector includes a smoke detector and a heat sensor, and the accumulation processing circuit closes the signal line within the accumulation time in a time shorter than the rise time of the smoke detector. The fire detection device according to claim 1, characterized in that an operation check of the heat sensor is performed.