JPH0589383A - Smoke analog-type method and device for judging fire - Google Patents

Abstract

PURPOSE:To properly judge fine by means of a receiver or repeating board, by utilizing effectively an analog smoke sensor displaying smoke density sent from the analog smoke sensor. CONSTITUTION:An analog receiver 1 compares the level of the analog smoke detecting signal transmitted from an analog smoke sensor 3 with the pre-alarm level so as to judge it as pre-alarm at the time of exceeding the pre-alarm level and compares the level of the analog smoke detecting signal transmitted from the analog smoke sensor 3 with the fire level which is higher than the pre-alarm level so as to judge it as fire at the time of exceeding the fire level. Moreover, the receiver 1 predictively calculates an ascending tendency based on past stored data when the analog smoke detecting signal transmitted from the analog smoke sensor 3 exceeds the operation start level, calculates smoke density after pre-alarm prediction time passes, which means after fixed time passes from the present point of time, and judges it as pre-alarm when calculated smoke density exceeds the fire level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a smoke analog fire judging method and device for judging a fire by sending an analog smoke detection signal indicating a smoke density detected by an analog smoke detector to a receiver or a relay board.

[0002]

2. Description of the Related Art Conventionally, in a fire judging method for judging a fire from the smoke density associated with a fire, a smoke detector itself connected to a signal line for both power source drawn from a receiver has a fire judging function. When a smoke detector receives a smoke concentration detection signal that exceeds the fire level, the switching element turns on the power supply signal line from the receiver to short-circuit to a low impedance, and the fire detection signal (ON signal) Is sent to the receiver.

However, turning on from such a smoke detector,
In the method of monitoring the off signal with the receiver and judging the fire,
Since all decisions on fire depend on smoke detectors, if the detection sensitivity of smoke detectors is increased in order to detect fires early, there are many false alarms due to causes other than fire. Also, if the detection sensitivity of the smoke detector is lowered to prevent false alarms, there will be a time delay in fire detection.

Therefore, in recent years, an analog smoke detection signal indicating the smoke density detected by a smoke sensor is sent to a receiver,
It is considered that a receiver judges a fire.

[0005]

However, in the fire judging method based on the analog detection signal in the conventional receiver, the fire judging method in the on / off type smoke detector is inherited and analog smoke is detected. The analog smoke detection signal indicating the smoke density sent from the detector is compared with a predetermined fire judgment level, and when it exceeds the fire judgment level, it is judged as a fire, and the conventional on / off type smoke is detected. It has not been possible to make a fire judgment by fully utilizing the analog detection signal, which has more information than the fire detection signal from the detector.

Further, in the conventional analog fire judgment,
To meet legal standards, even with an analog smoke detector, the ability of the on and off smoke detectors to send a fire detection signal to the receiver when the analog fire detection signal exceeds the fire level is still detected. Even if a fire detection signal is sent to the receiver by sending an analog smoke detection signal to the receiver, if a fire detection signal from the detector is received, it must be judged as a fire. Fire decisions based on analog smoke detection signals in Japan are only secondary.

The present invention has been made in view of the above conventional problems, and effectively utilizes the analog smoke detection signal indicating the smoke density sent from the analog smoke sensor to a receiver or a relay board. It is an object of the present invention to provide a fire judging method and device capable of making an appropriate fire judgment in the above.

[0008]

To achieve this object, the present invention is constructed as follows. First, according to the present invention, one or a plurality of analog smoke detectors are connected to a signal line drawn from a receiver, and an analog smoke detection signal corresponding to a smoke density accompanying a fire detected by the analog smoke detector is sent to the receiver. Smoke analog fire judgment method for sending and judging fire is targeted.

According to the present invention regarding such a smoke analog type fire judging method, the analog smoke detection signal sent from the analog smoke detector is compared with a predetermined pre-alarm level, and when the pre-alarm level is exceeded. It is judged as a pre-alarm, and the analog smoke detection signal sent from the analog smoke detector is compared with a predetermined fire level higher than the pre-alarm level, and when it exceeds the fire level, it is judged as a fire and When the analog smoke detection signal sent from the smoke detector exceeds the predetermined calculation start level, a pre-alarm that predicts an upward trend based on the past accumulated data and after a certain time from the current time The smoke concentration after the prediction time is calculated, and when the calculated smoke concentration exceeds the fire level, it is judged as a pre-alarm.

Further, according to the present invention, one or a plurality of analog smoke detectors may be connected to the signal line drawn from the receiver via a relay board, and the pre-alarm judgment and the fire judgment may be made in the relay board. .. On the other hand, according to the present invention, one or a plurality of analog smoke detectors are connected to a signal line drawn from a receiver, and an analog smoke detection signal corresponding to a smoke density associated with a fire detected by the analog smoke detector is received. Smoke analog type fire judgment device sent to the machine to judge the fire.The analog smoke detection signal sent from the analog smoke detector is compared with a predetermined pre-alarm level, and when the pre-alarm level is exceeded, the pre-alarm level is detected. A first pre-alarm determining means for determining an alarm and a predictive calculation of an upward trend based on the accumulated data when the analog smoke detection signal sent from the analog smoke detector exceeds a predetermined calculation start level. The smoke concentration after the pre-alarm prediction time, which is a certain time after the current time, is calculated, and when the calculated smoke concentration exceeds the fire level higher than the pre-alarm level, the pre-alarm is A second pre-alarm determination means for determining a fire alarm and a fire determination means for comparing the analog smoke detection signal sent from the analog smoke detector with a fire level and determining a fire when the fire level is exceeded. It is characterized by

Further, as the fire judging apparatus of the present invention, one or a plurality of analog smoke detectors are connected to the signal line drawn from the receiver through the relay board, and the relay board is provided with the first pre-alarm judging means and the first pre-alarm judging means. Two pre-alarm determination means and fire determination means may be provided. Here, in the receiver or the relay board, the fire level, the pre-alarm level, and the pre-alarm predicted time can be set and the set values can be changed for each analog smoke detector.

The fire level and the pre-alarm level are set to 1
By defining a plurality of groups having different values as a group and selecting any one of the plurality of groups, the fire determination level used by the fire determination means and the pre-alarm level used by the first pre-alarm means are set.

[0013]

According to the fire judging method and apparatus of the present invention having such a configuration, the pre-alarm level is set together with the original fire judging level for the analog smoke detection signal indicating the smoke concentration, and the smoke accompanying the fire is set. In response to an increase in the concentration, a two-stage alarm, that is, a pre-alarm based on the pre-alarm level and an original fire alarm based on the fire level, will be issued.

Therefore, at the pre-alarm stage, it is possible to start the preparatory work for dealing with the fire occurrence, and then it is possible to swiftly take measures when the original fire alarm is issued. If the original fire judgment based on the fire level cannot be reached even after the pre-alarm level has been set, preparations for the fire alarm are being made, but because the fire alarm is waiting in that state, the bell rings, etc. It is possible to immediately return to the steady monitoring state after confirming a false alarm without taking any unnecessary measures.

Furthermore, the pre-alarm level is calculated by predicting the smoke concentration rising tendency based on the past accumulated data and making a pre-alarm determination based on whether or not the fire level is exceeded after a predetermined pre-alarm prediction time. The pre-alarm judgment can be made at the stage where the calculation start level before reaching the above is reached, and a sufficient margin time until the original fire judgment can be secured, and an effective countermeasure against a fire can be taken.

[0016]

FIG. 1 is a block diagram of an embodiment showing one embodiment of the present invention. In FIG. 1, 1 is an analog receiver,
A power / combined signal line 2 is drawn out from the analog receiver 1 toward the warning area, and an analog smoke detector 3 and a repeater 4 are connected to the power / combined signal line 2.

The analog smoke detector 3 comprises a smoke detector and a transmission controller. A photoelectric smoke detector or an ionized smoke detector is used as the smoke detector, and outputs an analog smoke detection signal indicating the concentration of smoke flowing into the smoke detecting chamber of the sensor. The analog smoke detection signal from the smoke detection unit is converted into a current signal of, for example, 4 to 20 mA in response to a call from the analog receiver 1, and is sent out.

FIG. 2 is a time chart showing a transmission system between the analog receiver 1 and the analog smoke detector 3.
In FIG. 2, the analog receiver 1 sends a reset clock followed by a calling clock pulse indicated by numbers 1, 2, 3, ... 63. The reset pulse and ringing clock pulse are voltage signals that vary from 24 volts to 39.5 volts. For example, addresses 1 to 63 are pre-assigned to the analog smoke sensor 3 as addresses.

The transmission control unit of the analog smoke detector 3 counts the calling clock pulse obtained after the reset pulse, determines the calling of itself when the count value matches the address value set for itself, and determines the next call. The response data is transmitted using the timing of any one of the seven states 0 to 6 set with the call clock. In this embodiment, the state 5 is set as a state for returning an analog value, and the data obtained from the analog smoke detection signal of the smoke detection unit at the timing of the state 5 is used as the current in the range of 4 to 20 mA, for example. Send back with a signal.

In this embodiment, the terminal side can be controlled from the analog receiver 1 side, and any one of the four control timings of states 7 to 10 as shown between the call clocks 2 and 3. Can be added and set,
By transmitting the next call clock 3 at any one of the states 7 to 10, it is possible to instruct the terminal with the address number 2 to perform field control as appropriate.

Referring again to FIG. 1, a power / combined signal line 5 is drawn out from the repeater 4 provided in the terminal, and a conventional on / off type smoke detector 6 is connected to the power / combined signal line 5. ing. The analog receiver 1 is provided with a terminal transmission unit 7, a fire determination unit 8, a main control unit 9, a display operation unit 10, a setting unit 11, a notification unit 12, and a power supply unit 13. As shown in FIG. 2, the terminal transmission unit 7 follows the reset pulse by, for example, 6
The operation of sequentially transmitting the calling pulse for three terminals is repeated.
Further, at the time of control, the control is commanded by extending the timing of the state in which the next calling pulse is generated.

The fire judging section 8 executes a pre-alarm judgment and a fire judgment which will be clarified later on the basis of the analog smoke detection signal sent from the analog smoke detector 3 via the terminal transmitting section 7. The main control unit 9 performs overall control of each unit provided in the analog receiver 1. The display operation unit 10 performs various displays and operations associated with the determination process of the analog receiver 1. The setting unit 11 is the analog receiver 1
Set various data required for fire monitoring in. The transfer unit 12 outputs the pre-alarm determination result or the fire determination result obtained from the fire determining unit 8 via the main control unit 9 to the outside. Further, the power supply unit 13 produces a power supply voltage supplied from the commercial AC 100 V to the analog smoke detector 3 side through the operating power supply of the analog receiver 1 and the power / signal line 2.

FIG. 3 is a block diagram of an embodiment of the fire judging section 8 provided in the analog receiver 1 of FIG. In FIG. 3, 14
Is a CPU, and the first pre-alarm determining means 15 and the second pre-alarm determining means 1 are used to make the fire determination of the present invention.
6 and the function of the fire judging means 17 are realized by program control. For the internal bus 11 of the CPU 14, a ROM 18 storing a fire determination program, a RAM 19 for temporarily storing data used for fire determination, a fire determination means 17 and a first pre-alarm determination means 15 provided in the CPU 14 are used for determination. A first table 20 storing a fire level and a pre-alarm level, a second table 21 having a pre-alarm prediction time used by the second pre-alarm determining means 16 of the CPU 14, and a terminal transmission unit 7 shown in FIG.
1, a terminal transmission unit interface 22, a data memory 23 for storing the data from the analog smoke detector 3 in a sensor unit, and a main control unit interface 24 for the main control unit 9 in FIG.

In the data memory 23, three areas D, A and B are assigned to each analog smoke detector. Among these, in the D section, the analog smoke detection signal sent from the analog smoke detector 3 sampled every 10 seconds corresponds to the past 70 seconds and the seven smoke density data D
1 to D7 are stored. The moving average data A10 to A1 for 10 pieces obtained by the moving average calculation using the smoke density data of the D portion is stored in the A portion. Further, in section B, five moving average data B5 to B1 are stored, which are obtained by thinning out the data in section A at intervals of 30 seconds.

In the CPU 14 shown in FIG. 3, the first pre-alarm determination means 15 and the second pre-alarm determination means 1
6 types of pre-alarm judgment and fire judgment means 6
Fire decision is made. The first pre-alarm determining means 15 compares the analog data Ta obtained every 10 seconds with a predetermined pre-alarm level Tp, and outputs a pre-alarm output when the pre-alarm level Tp is exceeded.

When the moving average data calculated every 10 seconds exceeds the calculation start level set below the pre-alarm level, the second pre-alarm determining means 16 detects the A section of the corresponding sensor in the data memory 23 and Prediction calculation showing an increasing tendency of smoke density is performed based on the moving average data stored in the B section. This prediction calculation is performed by approximating the rising tendency of smoke density to the following quadratic equation using the method of least squares.

[0027]

[Equation 1]

Specifically, in the last 4 minutes, the data memory 2
Using the moving average data stored in the parts A and B of the corresponding sensor areas of 3, the coefficients A, B, C of the quadratic equation are obtained by the method of least squares. Specifically, the coefficients A, B, and C are calculated by the following arithmetic expression.

[0029]

[Equation 2]

(However, Xi is the time, and Yi is the moving average value of the sensor output at each time.)

Thus, the coefficients A, B, and
When C is obtained, it is possible to obtain the smoke concentration prediction value Cp after a predetermined time, for example, 120 seconds, which is set as the pre-alarm prediction time. Therefore, the predicted smoke concentration Cp is compared with the fire level TA used by the fire determination means 17, and if it exceeds the fire level TA, it is determined to be a pre-alarm and a pre-alarm output is output.

Next, the fire judging means 17 samples the analog data from the analog smoke detector 3 every 10 seconds to obtain the smoke concentration data Ta, compares it with the fire level TA set higher than the pre-alarm level, and compares it with the fire level TA. When it exceeds TA, it is judged as a fire and a fire alarm is issued. In the first table 20 of FIG. 3, the pre-alarm level Tp and the fire judging means 15 used by the first pre-alarm judging means 14 are shown.
As shown in FIG. 4, the fire level TA used in No. 1 is the level No. It is divided into 0 to 7 and stored. That is, the combination of the fire level TA and the pre-alarm level Tp is the level N
A group indicated by o is configured, and a unique smoke density is set for each group. For example, the level No. At 0, the fire level TA is 10% / m, and the pre-alarm level Tp is half that, Tp = 5% / m. Also,
Level No. In No. 1, the same level as the fire level TA = 4% / m and the pre-alarm level Tp = 4% / m is set.

Therefore, the setting of the pre-alarm level and the fire level for the first pre-alarm determining means 15 and the fire determining means 17 by the CPU 14 of FIG. 3 is performed by setting the level No. in the first table 20 shown in FIG. Is specified, the specific group is read, the TA value of the fire level of the specified group is set in the fire determination means 17, and the pre-alarm level Tp is the first pre-alarm determination means 15.
Will be set to.

FIG. 5 shows the pre-alarm prediction time set in the second table 21 of FIG. Corresponding to 0 to 3, 0 seconds, 60 seconds, 120 seconds, and 180 seconds are set as the pre-alarm prediction time. Therefore, the second pre-alarm determination means 16 provided in the CPU 14 of FIG. Is received, the corresponding pre-alarm prediction time is set, and the smoke concentration Cp predicted using the pre-alarm prediction time obtained from the second table 21 as the time t of the quadratic expression in (1) above. The fire level T
Compare with A.

FIG. 6 is an explanatory diagram showing the increase in smoke density at the time of fire on the time axis. In FIG. 6, with respect to the smoke concentration shown on the vertical axis, first, the calculation start level Cs for performing the prediction calculation is set at the bottom, the pre-alarm level Tp is set on it, and the fire level TA is set on it. Is set. Of course, the level No. of FIG. In the case of 1, the pre-alarm level Tp and the fire level TA are the same.

FIG. 6 is a plot of the storage data stored in the portions A and B of the data memory 23 of FIG. 3 by the current time t1, and the moving average data A10 at the current time t1 is the calculation start level Cs. Is exceeded,
At this point, the prediction calculation by the second pre-alarm determining means 16 in FIG. 3 is started. That is, using the equation (2), the coefficients A, B, in the quadratic equation of the equation (1),
C, and at this time, the pre-alarm prediction No. of the second table 21 in FIG. By substituting the pre-alarm prediction time t set by the above into the equation (1) in which the coefficients A, B, and C are determined, the smoke concentration Cp after the pre-alarm prediction time has elapsed is obtained. At this time, the predicted smoke concentration Cp is the fire level TA
Therefore, the pre-alarm determination output is generated at the current time t1, and the pre-alarm output is performed.

FIG. 7 is an explanatory diagram showing a method of calculating the moving average data A10 calculated at time t1 in FIG. The moving average data A10 at the current time t1 is calculated as A10 = (D1 + D2 + D3 + D4 + D5 + A7 + A8) / 7. That is, the moving average of seven data up to time t7, which is 10 seconds before the current time t1, is calculated. For five times t1 to t5, the analog data sent from the analog smoke sensor is sampled. The raw data D1 to D5 are used. But,
For times t6 and t7, the raw data D6 and D7 are not used, but the moving average data A8 and A7 calculated at the times t6 and t7 are used.

As described above, originally, there are seven moving averages of raw data, but the oldest time t7 and the second oldest time t6.
In regard to, even if the moving average data A7 and A8 already calculated are used instead of the raw data D7 and D6, there is almost no error. Rather, by setting the raw data to five of D1 to D5, the data area of the D part in the data memory 23 shown in FIG. 3 can be reduced from seven to five, which is originally necessary, to two, and the remaining two. For A, using A8 and A7 of part A that stores moving average data, as a result, D for each sensor
It is possible to reduce the capacity of the data memory 23 that uses parts A, B and B.

Next, the judgment processing by the fire judging unit 8 of the present invention shown in FIG. 3 will be described with reference to the flowchart of FIG. In FIG. 8, first, in step S1, the analog data Ta (smoke density) sent from the analog smoke detector is sampled and input every 10 seconds. Subsequently, the analog data Ta input in step S2 and the first analog data Ta shown in FIG.
Compare with the fire level TA set from the table,
If the analog data Ta is equal to or higher than the fire level TA, the process proceeds to step S9 and fire determination processing is performed. That is, it is judged that a fire has occurred, and a fire judgment output is sent to the main control unit 9, and the main control unit 9 executes the processing associated with a predetermined fire judgment, such as a fire alarm, a notification, and control of smoke-exhaust equipment.

On the other hand, in step S2, the analog data Ta
If is smaller than the fire level TA, the process proceeds to step S3, waits for the elapse of a 10-second cycle, and repeats the fire determination process for the analog data obtained in real time in steps S1 and S2 until 10 seconds is reached. When it is determined in step S3 that the 10-second cycle is reached, step S4
Then, the analog data Ta is stored as D1 in the B section of the corresponding sensor of the data memory 23 of FIG. Then, the moving average Ca is calculated by using the smoke density data of 7 points corresponding to the past 70 seconds. Specifically, as shown in FIG. 7, the five that are earlier in time use raw data, and the remaining two use moving average values that have already been calculated.

Next, in step S5, it is determined whether or not the calculated moving average Ca has reached the calculation start level Cs. If it has not reached the calculation start level Cs, the process returns to step S1 again and the processing up to step S4 is performed. repeat. When the moving average value Ca becomes equal to or higher than the calculation start level Cs in step S5, the process proceeds to step S6, the prediction calculation is executed based on the equations (1) and (2), and the second table 21 in FIG.
Predicted smoke density C after the pre-alarm predicted time t obtained from
Find p.

Subsequently, in step S7, it is determined whether or not the smoke concentration Cp obtained by the predictive calculation is equal to or higher than the fire level TA. If it is equal to or higher than the fire level TA, the process proceeds to step S10, it is determined that a pre-alarm is generated, and a pre-alarm determination output is made. Based on the pre-alarm warning process. On the other hand, if the predicted smoke concentration Cp is less than the fire level TA in step S7, the process proceeds to step S8 to compare the analog data Ta with the pre-alarm level Tp set in the first table of FIG. For example, the process proceeds to step S11, a pre-alarm is determined, and alarm processing based on the pre-alarm output is performed. If the analog data Ta is less than the pre-alarm level Tp in step S8, the process returns to step S1 and the same processing is repeated.

FIG. 9 is a block diagram of an embodiment showing another embodiment of the present invention. In this embodiment, the analog receiver 1 is used.
It is characterized in that the fire judgment of the present invention is performed by the analog relay board 30 connected to the trunk line 25 drawn from the. 9, the analog receiver 1 is provided with a trunk transmission unit 26 instead of the fire determination unit 8 and the terminal transmission unit 7 of FIG. A trunk line 25 is drawn out from the trunk line transmission unit 26, and for example, analog relay boards 30 provided on each floor are sequentially connected. The analog relay board 30 includes a trunk line transmission unit 27, and can send and receive data to and from the trunk line transmission unit 26 of the analog receiver 1 using the trunk line 25.

The analog relay board 30 is provided with the same fire judging section 8 and terminal transmitting section 7 as those provided in the analog receiver 1 of FIG. A signal line 2 which also serves as a power source is drawn out from the terminal transmission section 7, and an analog smoke detector 3 is connected to the signal line 2 which serves also as a power source.
And the repeater 4 are connected. The configuration and the processing operation of the fire determination unit 8 provided on the analog relay board 30 are the same as those shown in FIGS.

The pre-alarm judgment result and the fire judgment result by the fire judging unit 8 are sent from the trunk line transmitting unit 27 to the analog receiver 1 via the trunk line 25, and the main line transmitting unit 26 of the analog receiver 1 sends the main control unit 9 to the analog receiver 1. Given to the display operation unit 1
Pre-alarm warning processing and fire warning processing using 0,
Further, the transfer output using the transfer unit 12 is performed. The data transmission between the analog smoke sensor 3 and the analog receiver 1 or the analog relay board 30 in the above-described embodiment is based on the method using the ringing clock shown in FIG. It is also possible to adopt a data transmission system in which an address command is sent from the receiver side, and the address response data is sent back from the analog smoke detector 3 side that has received its own call.

The details of the predictive calculation performed by the second pre-alarm determining section 16 are described in JP-A-59-157789.

[0047]

As described above, according to the present invention, the analog smoke detection data sent from the analog smoke detector can be compared with the pre-alarm level and the fire level to give a two-stage fire alarm. Therefore, it is possible to make an appropriate fire judgment that combines early detection of a fire and effective prevention of false alarms by effectively utilizing the information amount of analog smoke data obtained continuously.

Further, by performing the predictive calculation, it is possible to determine whether or not there is a risk of fire at an early stage when the calculation start level is lower than the pre-alarm level, and it is possible to obtain sufficient margin time before the actual fire determination. , Appropriate preparations can be taken for subsequent fire decisions.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment showing an embodiment of the present invention.

FIG. 2 is a time chart showing a calling process of an analog smoke detector by the analog receiver of FIG.

FIG. 3 is a configuration diagram of an embodiment of a fire determination unit in FIG.

FIG. 4 is an explanatory diagram of a first table in FIG.

5 is an explanatory diagram of a second table in FIG.

FIG. 6 is a time chart showing the prediction calculation of the second pre-alarm determination means in FIG.

7 is an explanatory diagram showing a method of calculating moving average data used in the prediction calculation of FIG.

FIG. 8 is a flow chart showing the fire determination process of FIG.

FIG. 9 is a block diagram of an embodiment showing another embodiment of the present invention.

[Explanation of symbols]

 1: Analog receiver 2, 5: Power supply signal line 3: Analog smoke detector 4: Repeater 6: On / off type smoke detector 7: Terminal transmission unit 8: Fire determination unit 9: Main control unit 10: Display Operation part 11: Setting part 12: Transfer part 13, 28: Power supply part 14: CPU 15: First pre-alarm judging means 16: Second pre-alarm judging means 17: Fire judging means 18: ROM 19: RAM 20: No. 1 table 21: second table 22: terminal transmission interface 23: data memory 24: main control interface 25: trunk 26, 27: trunk transmission

Claims (6)

[Claims] 1. One or more analog smoke detectors are connected to a signal line drawn from the receiver, and the analog smoke detection signal corresponding to the smoke density associated with a fire detected by the analog smoke detector is received by the receiver. In the smoke analog type fire judging method for judging the fire by sending to the, the analog smoke detection signal sent from the analog smoke detector is compared with a predetermined pre-alarm level, and when the pre-alarm level is exceeded, It is judged as a pre-alarm, the analog smoke detection signal sent from the analog smoke detector is compared with a predetermined fire level higher than the pre-alarm level, and it is judged as a fire when the fire level is exceeded, and When the analog smoke detection signal sent from the analog smoke detector exceeds a predetermined calculation start level, the upward trend prediction calculation is performed based on the past accumulated data and the current time is calculated. Smoke analog type fire determination method characterized by determining a pre-alarm when calculating the smoke density after the pre-alarm estimated time to be after a certain time, is calculated smoke density exceeds the fire level from. 2. The smoke analog fire judging method according to claim 1, wherein one or more analog smoke detectors are connected to the signal line drawn from the receiver through a relay board, and the relay board is used. A smoke analog type fire judgment method characterized by making pre-alarm judgment and fire judgment. 3. One or more analog smoke detectors are connected to a signal line drawn from the receiver, and the analog smoke detection signal corresponding to the smoke density associated with the fire detected by the analog smoke detector is received by the receiver. In a smoke analog type fire judging device for judging a fire by sending to, the analog smoke detection signal sent from the analog smoke detector is compared with a predetermined pre-alarm level, and when the pre-alarm level is exceeded, A first pre-alarm determining means for determining a pre-alarm, and when the analog smoke detection signal sent from the analog smoke detector exceeds a predetermined calculation start level, a rising tendency based on past accumulated data Prediction calculation is performed to calculate the smoke density after the pre-alarm prediction time, which is a certain time after the current time, and the calculated smoke density exceeds the fire level higher than the pre-alarm level. And a second pre-alarm determining means for determining a pre-alarm, and an analog smoke detection signal sent from the analog smoke detector is compared with the fire level, and a fire determination for determining a fire when the fire level is exceeded. A smoke analog type fire judging device characterized by comprising: 4. The smoke analog type fire judging device according to claim 4, wherein one or a plurality of analog smoke detectors are connected to a signal line drawn from a receiver via a relay board, and the signal board is connected to the relay board. A smoke analog type fire judging device comprising the first pre-alarm judging means, the second pre-alarm judging means and the fire judging means. 5. The fire judging device according to claim 3 or 4, wherein a fire level, a pre-alarm level and a pre-alarm predicted time can be set and the set value can be changed for each of the analog smoke detectors. The fire determination device characterized in that 6. The fire judging device according to claim 1, wherein a plurality of groups having different values are defined with the fire level and the pre-alarm level as one group, and any one of the plurality of groups is selected. A fire determination device characterized by setting a fire determination level used by the fire determination means and a pre-alarm level used by the first pre-alarm means.