JP2009295034A - Fire decision device and fire alarm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fire decision device which effectively determines a fire and operates with low power consumption, and a fire alarm using the fire decision device. <P>SOLUTION: The fire decision device includes a smoke sensor 4, a CO sensor 3, a calculation means 2 of calculating a smoke density gradient Gs, a smoke density difference maximum value ¾d¾max, and a CO density gradient Gco, and an elapsed time measuring means 2 of measuring an elapsed time Ts until smoke density reaches first set smoke density and second set smoke density, and determines a fire on the basis of the smoke density gradient Gs, the smoke density difference maximum value ¾d¾max, the elapsed time Ts, and the CO density gradient Gco. Further, the fire decision device includes a decision operation stop means of stopping the operation for determining a fire when the smoke density exceeds the first set smoke density and then the smoke density becomes below the first set smoke density without exceeding the second set smoke density a predetermined number of times or more within a predetermined period. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fire / non-fire discrimination device and a fire alarm using the fire / non-fire discrimination device.

  Conventional fire alarms include, for example, a thermal sensor that detects temperature rise, a smoke sensor that detects smoke, a flame sensor that detects flame, and a CO sensor that detects carbon monoxide (CO) concentration. There are a single type having a sensor and a composite type having these sensors combined. A ministerial ordinance that establishes technical standards for residential fire alarms and automatic fire alarm equipment for houses stipulates having smoke sensors.

  A smoke fire alarm with a smoke sensor reacts to dust accumulation and cigarette smoke in the living room, and reacts to smoke and water vapor generated during cooking in the kitchen. May occur. For this reason, smoke fire alarms have not been approved for use in the kitchen. However, in recent years, it has become mandatory to install fire alarms in single-family homes, and smoke-based fire alarms have been adopted in the technical standards, and smoke-type fire alarms can be used in the kitchen. It is becoming increasingly important.

  In addition, from an experiment simulating a house fire, there is a fire in which the toxic CO concentration rises before the amount of smoke increases, such as futon kun burning with sleeping cigarettes. Sometimes, in the worst case, there is a risk that the CO concentration or carbon monoxide hemoglobin (COHb) will reach a dangerous area before the smoke fire alarm is given, and will be delayed.

  On the other hand, an international standardization organization (ISO) has proposed an alarm device that detects CO generated together with smoke at the time of a fire and issues an alarm when the CO concentration exceeds a threshold value. The threshold value of CO concentration is determined based on the experiment of EN standard fire test standard TF3, and the threshold value is as low as 50 ppm. However, since the CO concentration generated from the combustion equipment (stove, fan heater, etc.) used on a daily basis can be higher than 50 ppm, such a low CO concentration threshold is used to operate the combustion equipment. May react and give a false alarm.

  As described above, with conventional fire alarms, even if a physical quantity such as smoke that exceeds the threshold is detected, is it due to a fire, or is it due to a non-fire caused by cooking or use of a combustor? It was not possible to make a judgment, and a false alarm was generated or a fire could not be detected early.

In order to solve the above problems, as a conventional fire alarm device, as a method for discriminating between fire and non-fire, 1) a method of changing an operation level according to smoke rising time and comparing it with a threshold (for example, Patent Document 1) 2) A method for setting a fire area and a non-fire area and selecting which area from smoke and CO concentration (for example, refer to Patent Document 2), 3) of smoke and CO concentration A method of determining a fire based on a change rate (for example, see Patent Document 3) has been proposed.
JP 2006-146738 A JP 2006-146843 A JP 2006-277138 A

  In the case of a fire, depending on the type and amount of combustibles, smoke may be emitted gradually or suddenly from a certain point. In the former case, it is possible to distinguish between fire and non-fire by the above-described conventional method, but it is not clear whether the latter case can be effectively distinguished.

  Further, when the fire alarm is a battery-driven type, it is required to extend the life of the battery by suppressing power consumption as low as possible. Further, the sensor output fluctuates due to external noise, and the power consumption may increase due to unnecessary operation of the fire alarm.

  Therefore, in view of the above-described problems, the present invention can effectively distinguish between a real fire and a non-fire, and operates with low power consumption. A fire using the fire / non-fire discrimination device The purpose is to provide an alarm.

  The invention according to claim 1, which has been made to solve the above-mentioned problems, includes a smoke sensor for detecting a smoke concentration, a CO sensor for detecting a CO concentration, and a smoke concentration detected at a predetermined detection timing by the smoke sensor. Is linearly approximated based on a plurality of measured data of the smoke density that continuously varies between the first set smoke density and the second set smoke density set higher than the first set smoke density. The slope of the linear expression is calculated as the smoke density slope Gs, and the maximum difference between the smoke density measured data and the smoke density value represented by the primary expression is calculated as the smoke density difference maximum value | d | max. Calculating means for calculating, as a CO concentration gradient Gco, a slope of a linear expression approximated linearly based on a plurality of measured CO concentration data detected at the same time as the measured data of the smoke concentration Cs; The slope Gs is preset. Smoke density gradient determining means for determining whether or not the smoke density gradient threshold value is less than or not, and whether or not the smoke density difference maximum value | d | max is less than a preset smoke density difference threshold value A smoke density difference determining means for determining the elapsed time, an elapsed time measuring means for measuring an elapsed time Ts until the smoke density reaches the second set smoke density from the first set smoke density, and the elapsed time measuring means The elapsed time determination means for determining whether or not the elapsed time Ts measured in step S1 exceeds a preset elapsed time threshold, and the CO concentration gradient Gco is a predetermined CO concentration gradient threshold. A combination of the determination results of the CO concentration gradient determination means for determining whether or not the value exceeds the smoke concentration gradient determination means, the smoke concentration difference determination means, the elapsed time determination means, and the CO concentration gradient determination means. But A combination for determining each of the determination results of the smoke determination means, the smoke concentration difference determination means, the elapsed time determination means, and the CO concentration inclination determination means as the fire In the fire / non-fire discrimination device for judging fire / non-fire, the smoke concentration exceeds the first set smoke concentration. Discriminating to stop the fire / non-fire discriminating operation when the number of times when the number of times that the second set smoke concentration is less than the first set smoke concentration becomes equal to or greater than the predetermined number within a predetermined period. An operation stop means is further provided.

  The invention according to claim 2 made to solve the above-mentioned problem is a fire alarm using the fire / non-fire discrimination device according to claim 1, wherein the fire / non-fire discrimination device discriminates a fire. If so, a fire / non-fire discrimination operation is performed by the first fire determination means for determining whether or not the smoke concentration exceeds a predetermined first fire determination smoke threshold, and the determination operation stop means. A second fire determination means for determining whether or not the smoke concentration is higher than the first fire determination smoke threshold and exceeds a predetermined second fire determination smoke threshold; When the first fire determination means determines that the smoke concentration exceeds the first fire determination smoke threshold, or the second fire determination means determines that the smoke concentration is the second fire determination smoke. If it is determined that the threshold has been exceeded, a fire alarm is reported. And informing means for, characterized in that it comprises.

  The invention according to claim 3, which has been made to solve the above problem, sets a predetermined delay time in the fire alarm device according to claim 2 when it is determined that the fire / non-fire discrimination device is non-fire. And a delay time setting means for determining whether or not the smoke concentration has exceeded the second fire determination smoke threshold over the predetermined delay time set by the delay time setting means. A fire determination unit, and the notification unit further notifies a fire alarm when the third fire determination unit determines that the smoke concentration exceeds the second fire determination smoke threshold value. It is characterized by that.

  According to the first aspect of the present invention, since fire / non-fire is discriminated based on the smoke density gradient Gs, the smoke density difference maximum value | d | max, the elapsed time Ts, and the CO density gradient Gco, it is particularly preferable to use fire and cooking. It is possible to effectively distinguish non-fire due to. In addition, when the number of times that the smoke density is less than the first set smoke density without exceeding the second set smoke density after the smoke density exceeds the first set smoke density is greater than or equal to the predetermined number within a predetermined period, Since a discrimination operation stop means for stopping the fire / non-fire discrimination operation is further provided, the wasteful fire / non-fire discrimination operation due to external noise can be stopped to reduce power consumption.

  According to the second aspect of the present invention, when the fire / non-fire discriminating apparatus determines that a fire has occurred, the smoke concentration exceeds the first fire determination smoke threshold value, or the discrimination / operation stop means causes the fire / non-fire. When the fire detection operation is stopped, a fire alarm is notified when the smoke concentration exceeds the second fire determination smoke threshold value, which is higher than the first fire determination smoke threshold value. It is possible to make a distinction and make a reliable notification.

  According to the third aspect of the present invention, when it is determined that the fire / non-fire determination device is non-fire, the smoke concentration is set to the second fire determination smoke threshold over the set delay time. A fire alarm can be notified when it exceeds.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a fire alarm using a fire / non-fire discrimination device according to the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a fire alarm using a fire / non-fire discrimination device according to an embodiment of the present invention. The fire alarm 1 includes a microcomputer (hereinafter referred to as a microcomputer) 2, a CO sensor 3, a smoke sensor 4, an alarm output unit 5, an external output unit 6, and a storage unit 7.

  The microcomputer 2 includes a CPU 2a, a ROM 2b, and a RAM 2c, and the CPU 2a executes various processes including control according to the present embodiment in accordance with a control program stored in the ROM 2b. The RAM 2c appropriately stores data, programs, and the like necessary for the CPU 2a to execute various processes.

  The CO sensor 3 detects the CO concentration in the air and outputs a sensor output corresponding to the CO concentration. The CO sensor 3 may be any sensor that can detect the CO concentration. For example, a catalytic combustion type, an electrochemical type, an NDIR type, or the like is used.

  The smoke sensor 4 detects the amount of smoke in the air and outputs a sensor output corresponding to the amount of smoke. There are various types of smoke sensors. In this embodiment, as the smoke sensor 4, a photoelectric type including a light emitting element and a light receiving element that receives irregularly reflected light from smoke particles is used.

  The alarm output unit 5 is for outputting a fire alarm under the control of the microcomputer 2, such as a sound output circuit such as a buzzer or a speech processor that emits an alarm sound or an alarm voice message, or a display output circuit such as an LED or LCD that displays an alarm. Etc. are configured. The external output unit 6 includes a communication circuit that transmits an alarm signal output from the microcomputer 2 to an external system, a security center, or the like.

  The memory | storage part 7 is a non-volatile memory means comprised by EEPROM (Electrically Erasable and Programmable ROM) etc., for example. The storage unit 7 stores a first set smoke density, a second set smoke density, an elapsed time threshold value, a smoke density gradient threshold value, and a CO concentration gradient preset for use in the determination process described later. A threshold value, a smoke concentration difference threshold value, a first fire determination smoke threshold value, a second fire determination threshold value, and a CO alarm concentration value are stored.

  Next, operation | movement of the fire alarm 1 which has the above-mentioned structure is demonstrated. In the present invention, in order to solve the above-described problems, the cooking test and the fire test shown in FIGS. 2 and 3 are performed, and a fire / non-fire discrimination method is obtained based on the test results.

  FIG. 2 shows the cooking test results. In FIG. 2, as cooking test items, the types and conditions of the objects are “Sanma 1 animal_GT + R (1)”, “Sanma 1 animal_R (2)”, “Sanma 1 animal_R (3)”, “Meat “Vegetable_GT + R (1)”, “Meat vegetable_GT + R (2)”, “Meat vegetable_GT + R (3)”, “Meat_Ventilation-free (1)”, “Meat_Ventilation-free (2)” and “Meat_Ventilation-free” (3) ”, the smoke density gradient Gs between Csth1 (% / m) <smoke density Cs <Csth2 (% / m) (smoke density Cs is set lower than the fire judgment smoke threshold The first set smoke density Csth1 (for example, 2.5)% / m, and the second set smoke density Csth2 (for example, 6) that is set lower than the fire determination smoke threshold and higher than the first set smoke density. ) Smoke density gradient in smoke density change characteristics during continuous fluctuations between% / m), (Actual measurement value) − (primary formula) | maximum smoke density difference | d | max and elapsed time Ts between Csth1 <Cs <Csth2 (while smoke density Cs continuously varies between Csth1 and Csth2) Elapsed time) and CO concentration gradient Gco between Csth1 <Cs <Csth2 (CO concentration change characteristic while smoke concentration Cs continuously fluctuates between first set smoke concentration Csth1 and second set smoke concentration Csth2) (CO concentration gradient).

  Here, for example, in “One Sanma_GT + R (1)”, one Sanma is a test that uses a fish grilling net to burn Sanma and generate smoke. GT is a display when the ventilation fan directly above the gas table is operated, and R is a ventilation fan installed on the ceiling. (1) indicates that the number of tests is the first. “Meat vegetable_GT + R” is a product in which pork belly is fried to some extent in a frying pan, vegetables are added, smoke is generated, and ventilation fans GT and R are operated. “Meat_No ventilation” means that when the pork loin is baked in a frying pan and smoke is generated, the ventilation fan is not activated.

  FIG. 3 shows the fire test results. In FIG. 3, as the fire test items, smoke density gradient Gs and maximum smoke density difference | d for sinter, stove duvet (100% cotton), stove duvet (50% cotton poly), tempura and urethane | Max, elapsed time Ts, and CO concentration gradient Gco.

  For example, “Kun-yaki (1)” represents the first test in which a fire that caused a smoldering fire was generated by sandwiching a heater serving as a fire source between 100% cotton futon and heating at 450 ° C. for 17 minutes. ing. "Stove futon (100% cotton)" is a situation where a 100% cotton futon is placed in contact with a heater so as to face a reflective electric stove with a 1kW reflector, and the stove is ignited to generate a fire. Tested. “Stove duvet (50% cotton poly)” is the same test as a stove duvet (100% cotton) on a 50% cotton 50% polyester duvet. “Tempura” is made by putting salad oil in a pan and continuously heating it with a gas stove to ignite it. “Urethane” is a product that ignites nude urethane with a lighter or the like to cause a fire.

  The fire test was conducted in a fire test room simulating the residence of a general house, and the cooking test was conducted in a cooking test room simulating a kitchen of a general house.

  FIG. 4 is a diagram schematically showing a cooking test room simulating a kitchen of a general house. As shown in FIG. 4, in a room in which a gas table GR is arranged at one corner of a room, a large ventilation fan GT is arranged on the upper wall, and a small ventilation fan R is arranged on the ceiling, the gas table GR is used and The cooking test was performed with the ventilation fans GT and R not being driven. Then, CO concentration and smoke concentration data were collected for the case where measurement was performed with the fire alarm 1 arranged on the wall facing the wall with the door D, that is, the right wall of the gas table GR.

  FIG. 5 is a diagram schematically showing a fire test chamber. As shown in FIG. 5, with the fire alarm 1 placed on the top of the wall facing the wall with the sliding door HD and the vent V and the fire source placed near the center of the floor, the CO concentration and smoke concentration Data was collected.

The calculation method of the smoke density gradient Gs and the smoke density difference maximum value | d | max in FIGS. 2 and 3 is as follows. For example, consider a case where the smoke density Cs generated by fire or cooking changes as shown in FIG. 6 while increasing from Csth1 to Csth2. In FIG. 6, the smoke sensors 4 measure the measurement times t0, t1, t2, t3,. . . , Tn are measured data of smoke density Cs detected at Cs0, Cs1, Cs2, Cs3,. . . , Csn. The trapezoidal area formed by the smoke density Cs0 at time t0 and the smoke density Cs1 at time t1 (time integrated value of the smoke density Cs) is A1, and is formed by the smoke density Cs1 at time t1 and the smoke density Cs2 at time t2. The area of the trapezoidal part is A2, and the area of the trapezoidal part formed in the same manner is A3,. . . . , An, and the area of each trapezoidal part is obtained. Finally, the total area (time integrated value of smoke density Cs from time t0 to tn) S, which is the sum of all trapezoidal parts from time t0 to time tn, is as follows: Ask.
S = ΣAn (1)

Next, the smoke density Cs0 at the time t0 and the area of the rectangular portion formed between the times t0 and tn (a constant portion of the integrated value of the smoke density Cs from the time t0 to tn) Ss are obtained as follows.
Ss = Cs0 × (tn−t0) (2)

Next, the area Ss of the rectangular portion is subtracted from the total area S, and an upper area (a variation portion of the integrated value of the smoke density Cs from time t0 to tn) St obtained by removing the rectangular portion from the trapezoidal portion is obtained.
St = S−Ss (3)

Next, assuming a triangle having an area comparable to the obtained St between times t0 and tn, and assuming that the height is h, it can be expressed by the following equation.
St = {(tn−t0) × h} / 2 (4)

Next, the height h is obtained from the above equation (4).
h = 2St / (tn-t0) (5)

Next, when the obtained height h is divided by (tn−t0), the smoke concentration gradient Gs (% / m / sec) is obtained as follows as the average gradient of the smoke concentration Cs from the time t0 to the time tn. .
Gs = h / (tn−t0) = 2St / (tn−t0) ² (6)

As described above, the smoke density gradient Gs can be obtained. Then, when the change in the smoke density Cs during the time t from the time t0 to the time tn is expressed in the form of the primary expression y = ax + b, the following has the smoke density gradient Gs (= a) obtained as described above. The linear expression can be approximated by a linear expression.
Cs = {2St / (tn−t0) ² } t + b (7)
Here, t is time and b is an intercept.

  And the measured data Cs0, Cs1, Cs2, Cs3,. . . , Csn and the smoke density value represented by the linear expression approximated by the above-mentioned linear approximation, the maximum value is calculated as the smoke density difference maximum value | d | max.

  The CO concentration gradient Gco can also be obtained in the same manner as the method for calculating the smoke concentration gradient Gs described above based on the CO concentration during the time t0 to tn, but the description thereof is omitted here.

  FIG. 7 shows, as an example, (a) a graph representing the measured value of the smoke concentration Cs and the linear expression obtained as described above from the measured value in the case of the cooking test “one samurai_GT + R”, and (b ) It is a graph showing the density difference between the measured value and the primary expression. In the graph of FIG. 7A, the linear expression is represented by Cs = 0.01t−2.106. From the graph of FIG. 7B, the maximum value of | (actual value) − (primary expression) | It can be seen that d | max is 1.438.

  From the experimental results shown in FIGS. 2 and 3, the parameters for fire / non-fire determination are set to Gs <so that the object of the fire test is determined to be fire and the object of the cooking test is determined to be non-fire. th1 (th1 is an optimum value by verification with an actual machine, for example, in a range of 0.15 to 0.18), | d | max <th2 (th2 is an optimum value by verification with an actual machine, For example, it is in the range of 1.4 to 1.7.), Ts> th3 (th3 is an optimum value by verification with an actual machine, for example, in the range of 20 to 50 seconds) and Gco> th4 ( th1 is an optimum value obtained by verification with an actual machine, and is set in a range of 0.4 to 0.6, for example.

Combining the parameters set as described above, the following judgment conditions are used to distinguish between fire and non-fire and whether the fire is a smoldering fire or a general fire other than a smoldering fire. I did it.
Discrimination condition A. If Gs <th1 and Gco> th4, it is determined that the fire is fired.
Discrimination condition B. If Gs <th1 and | d | max <th2 and Ts> th3, it is determined as a smoldering fire.
Discrimination condition C.I. If | d | max <th2 and Gco> th4, it is determined as a general fire.
Discrimination condition D. If Gs <th1 and | d | max <th2, it is determined as a general fire.
Discrimination condition E.E. If none of the above applies, it is determined as non-fire.
The priority order of each condition is A>B>C>D> E.

  FIG. 8 is a diagram showing a fire / non-fire discrimination pattern based on the discrimination conditions described above. In this fire / non-fire discrimination pattern, th1, th2, th3, and th4 are set as a smoke concentration gradient threshold value, a smoke concentration difference threshold value, an elapsed time threshold value, and a CO concentration gradient threshold value, respectively. Stored in the unit 7.

  As a result of the determination based on the above-mentioned fire / non-fire determination conditions, when it is determined that the fire is a smoldering fire, a fire alarm is notified when the smoke concentration Cs rises to, for example, 8% / m. The general fire judgment smoke threshold is 10% / m. In the present invention, the smoke detection sensitivity is set by setting a smoke density lower than that as the fire judgment smoke threshold for fire smoldering judgment. increase. When it is determined that the fire is a general fire, a fire alarm is notified when the smoke density Cs rises to, for example, 10% / m.

  On the other hand, as a result of the determination based on the above-mentioned fire / non-fire determination conditions, when it is determined that the fire is not a fire, the fire determination smoke threshold is set to a general 10% / m, and the smoke density Cs is 10%. When it is continuously detected a predetermined number of times (for example, 20 times) that exceeds / m, a fire alarm is notified. That is, in this case, the fire alarm is notified with a delay by a time required for continuous detection a predetermined number of times (for example, 20 times) from the time when the smoke concentration Cs exceeds the first 10%.

  Next, refer to the flowcharts shown in FIGS. 11 to 19 for the detailed operation of the fire detection process of the fire alarm executed by the control of the CPU 2a of the microcomputer 2 based on the setting of the fire / non-fire discrimination condition as described above. While explaining.

  In FIG. 11, the CPU 2a performs a fire monitoring process after turning on the power, and first determines whether the monitoring state is waiting, measuring, or alarm monitoring (step S1). If the monitoring state is standby, then fire monitoring (standby) processing is performed (step S2), and then the process returns to step S1. If the monitoring state is being measured, then fire monitoring (during measurement) processing is performed (step S3), and then the process returns to step S1. If the monitoring state is alarm monitoring, then fire monitoring (alarm monitoring) processing is performed (step S4), and then the process returns to step S1.

  For details of the fire monitoring (standby) process in step S2, as shown in FIG. 12, it is first determined whether or not a predetermined long measurement interval tb (for example, 10 seconds) has elapsed (step S11). If so, the sensor outputs of the CO sensor 3 and the smoke sensor 4 are read every tb seconds (step S12). Next, based on the read sensor outputs of the CO sensor 3 and the smoke sensor 4, the CO concentrations Cco and Conversion calculation processing for obtaining the smoke density Cs is performed and stored in the storage unit 7 (step S13).

  Next, it is determined whether or not the obtained smoke density Cs exceeds a preset first set smoke density Csth1 (step S14). If the smoke density Cs does not exceed Csth1, then the process returns to step S11, and if it exceeds, then it is determined whether or not the logic invalid flag is “0” (step S15).

  Here, the logic invalid flag is the above-mentioned stop in order to prevent wasteful power consumption due to repeated operation / stop of the fire / non-fire discrimination logic described later due to external noise. This flag is stored in the storage unit 7 in order to stop the logic for fire / non-fire determination when the operation is repeated a predetermined number of times.

  FIG. 9 is a diagram for explaining an example of the external noise, and shows a noise waveform in the sensor output of the smoke sensor 4 with respect to the trigger waveform of the oscilloscope. This example shows how the sensor output fluctuates due to noise from the inverter of the fluorescent lamp, and a periodic fluctuation in which the maximum amplitude Csi corresponds to about 5% / m of the smoke density is seen. In the present invention, as will be described later, since the fire / non-fire discrimination logic operates based on the actually measured data in the smoke concentration range from Csth1 to Csth2, the external noise that falls within the range of Csth1 to Csth2 as described above. On the other hand, the logic repeatedly operates and stops unnecessarily, which consumes battery power.

  Therefore, when the logic for fire / non-fire discrimination is to be stopped, this flag is set to “1” and stored in the storage unit 7, and the logic for fire / non-fire discrimination is not to be stopped (ie, When the logic for fire / non-fire determination is operating), this flag is set to “0” and stored in the storage unit 7.

  If the logic invalid flag is “0”, the monitoring state is then switched to measurement (step S16), and the process is then terminated. If the logic invalid flag is not “0” (that is, if the logic for fire / non-fire discrimination is stopped), then the monitoring state is switched to alarm monitoring (step S17), and then the fire type Is determined to be a general fire (step S18), and then the process is terminated.

  As described above, when the smoke density Cs is equal to or higher than Csth1, if the logic invalid flag is “0”, the operation of the above-described steps S15 to S18 is performed by switching the monitoring state to measuring and performing a fire.・ If the non-fire detection logic is activated and the logic invalid flag is “1”, the monitoring state is switched to alarm monitoring without performing fire / non-fire detection, and alarm monitoring is performed as a general fire. It is what is started.

  For details of the fire monitoring (measuring) process in step S3, as shown in FIG. 13, it is first determined whether or not a predetermined short measurement interval ta (for example, 1 second) has elapsed (step S31). If so, the sensor outputs of the CO sensor 3 and smoke sensor 4 are read every time ta seconds elapse (step S32). Next, based on the read sensor outputs of the CO sensor 3 and smoke sensor 4, the CO concentration Cco and Conversion calculation processing for obtaining the smoke density Cs is performed and stored in the storage unit 7 (step S33).

  Next, it is determined whether or not the obtained smoke density Cs exceeds a preset second set smoke density Csth2 (step S34). If the smoke density Cs exceeds Csth2, then a fire logic determination process is performed (step S35), then the monitoring state is switched to alarm monitoring (step S36), and then the process ends.

  If the smoke density Cs does not exceed Csth2, then the count of the elapsed time Ts is incremented by 1 (the count value is updated by 1 every ta seconds) (step S37: elapsed time measuring means). The reason why the first set smoke density Csth1 is set to 2.5% is that the output fluctuation error of the smoke sensor 4 is estimated to be about 1% / m, for example, and an unnecessary fire / This is to prevent the non-fire discrimination logic from operating. In addition, the reason why the second set smoke density is 6% is that the appraisal standard is “do not ring for 5 minutes at 5% / m”, and the fire determination threshold value in the fire determination described later is 7 to 7 This is for setting in a range of 10% / m.

  Next, it is determined whether or not the smoke density Cs is lower than the first set smoke density Csth1 (step S38). If the smoke density Cs is not lower than the first set smoke density Csth1, then the process returns to step S34. If the smoke density Cs is lower than the first set smoke density Csth1, the monitoring state is then switched to standby (step S39), and then the count value of the logic stop count counter stored in the storage unit 7 is added. 1 (step S40), and then it is determined whether or not the count value of the number of logic stoppages is equal to a preset stoppage number threshold Kth (for example, 5 to 20 times) (step S41). If the logic stop count is equal to the stop count threshold value Kth, then the logic invalid flag is set to “1” (step S42), and then the process is terminated. If the logic stop count is not equal to the stop count threshold value Kth, the processing ends.

  The logic stop count and the logic invalid flag stored in the storage unit 7 are cleared every predetermined period, for example, every 25 hours measured by a separate 25 hour timer. Since this clearing is performed every 25 hours, the time for clearing is shifted by one hour per day. Then, if the logic stop occurs for the number of times equal to the stop count threshold value Kth within 25 hours, the logic invalid flag is set to “1”. When the logic invalid flag is set to “1”, in the fire monitoring (standby) process shown in FIG. 12, the operation of the fire alarm device shifts to fire monitoring (alarm monitoring), and discrimination between fire and non-fire is performed. Proceed to the general fire determination process described later without performing the operation.

  FIG. 10 is a diagram for explaining the timing of external noise and logic invalidation. In FIG. 10, the discriminating logic is repeatedly turned on and off for periodic external noise that falls within the smoke density Csth1 to Csth2 range, and this on / off is more than the stop count threshold value Kth within 25 hours. If it occurs, this indicates that the fire / non-fire discrimination logic after that point is invalidated.

  For details of the fire logic determination process in step S35, first, as shown in FIG. 14, the smoke concentration gradient Gs, the CO concentration gradient Gco, and the smoke concentration difference maximum value | d | max are calculated (step S51: calculation means). The smoke density gradient Gs and the smoke density difference maximum value | d | max are calculated, for example, when the smoke density Cs converted from the sensor output from the smoke sensor 4 measured every second is continuously between Csth1 and Csth2. It is calculated by the above-described calculation method based on actually measured data of a plurality of smoke concentrations Cs that fluctuate periodically. The slope Gco of the CO concentration Cco is calculated by, for example, a plurality of smokes in which the smoke concentration Cs converted by the sensor output from the smoke sensor 4 measured every second continuously varies between Csth1 and Csth2. The calculation is based on the actual measurement data of the concentration Cs and the actual measurement data of the CO concentration Cco detected at the same time. When the actual measurement data is equal to or lower than Csth1, the calculation is canceled, and from the time when Csth1 is exceeded, the measurement data of a plurality of smoke concentrations Cs that continuously vary between Csth1 and Csth2 is again used. Is calculated.

  Next, the Gs_flag, | d | max_flag, Ts_flag, and Gco flag are all set to “0” and stored in the storage unit 7 (step S52).

  Next, it is determined whether or not the smoke concentration gradient Gs is less than a preset smoke concentration gradient threshold th1 (step S53: smoke concentration gradient determining means). If the smoke density gradient Gs is less than th1, then the Gs_flag stored in the storage unit 7 is rewritten from “0” to “1” (step S54), and then the process proceeds to step S55. If the smoke density gradient Gs is not less than th1, the process proceeds directly to step S55.

  In step S55 (smoke density difference determination means), the CPU 2a determines whether or not | d | max is less than a preset smoke density difference threshold th2. If | d | max is less than th2, then the | d | max_flag stored in the storage unit 7 is rewritten from “0” to “1” (step S56), and then the process proceeds to step S57. If | d | max is not less than th2, the process proceeds directly to step S57.

  In step S57 (elapsed time determination means), the CPU 2a determines whether or not the elapsed time Ts exceeds a preset elapsed time threshold th3. If the elapsed time Ts exceeds th3, the CPU 2a then rewrites the Ts_flag stored in the storage unit 7 from “0” to “1” (step S58), and then proceeds to step S59. If Ts does not exceed th3, the process proceeds directly to step S59.

  In step S59 (CO concentration gradient determination means), the CPU 2a determines whether or not the CO concentration gradient Gco exceeds a preset CO concentration gradient threshold th4. If the CO concentration gradient Gco exceeds th4, the Gco_flag stored in the storage unit 7 is then rewritten from “0” to “1” (step S60), and then the process proceeds to step S61. If Gco does not exceed th4, the process proceeds directly to step S61. Next, it is determined whether or not the CO concentration is equal to or higher than the CO alarm concentration (for example, 300 ppm) (step S61). If the CO concentration is equal to or higher than the CO alarm concentration, then the Gco_flag stored in the storage unit 7 is rewritten from “0” to “1” (step S62), and then the process proceeds to step S63. If Gco does not exceed th4, the process proceeds directly to step S63.

  Next, the CPU 2a determines whether or not the Gs_flag stored in the storage unit 7 is “1” and the Gco_flag is “1” (step S63). If the Gs_flag is “1” and the Gco_flag is “1”, then the fire type is determined as smoldering fire based on the fire / non-fire determination pattern shown in FIG. 8 (step S64), and then the process is performed. finish.

  If the Gs_flag is not “1” and the Gco_flag is not “1”, then it is determined whether the Gs_flag is “1”, the | d | max_flag is “1”, and the Ts_flag is “1”. (Step S65). If the Gs_flag is “1”, the | d | max_flag is “1”, and the Ts_flag is “1”, then the fire type is set to smoldering fire based on the fire / non-fire discrimination pattern shown in FIG. It discriminate | determines (step S66) and then complete | finishes a process.

  If the Gs_flag is “1” and the | d | max_flag is not “1” and the Ts_flag is not “1”, then whether the | d | max_flag is “1” and the Gco_flag is “1”. Is determined (step S67). If the | d | max_flag is “1” and the Gco_flag is “1”, then the fire type is determined to be a general fire based on the fire / non-fire determination pattern shown in FIG. 8 (step S68). The process proceeds to step S72.

  If the | d | max_flag is not “1” and the Gco_flag is not “1”, then it is determined whether the Gs_flag is “1” and the | d | max_flag is “1” (step S69). . If the Gs_flag is “1” and the | d | max_flag is “1”, then the fire type is determined to be a general fire based on the fire / non-fire determination pattern shown in FIG. 8 (step S70). The process proceeds to step S72.

  If the Gs_flag is not “1” and the | d | max_flag is not “1”, then the fire type is determined to be non-fire based on the fire / non-fire determination pattern shown in FIG. 8 (step S71). The process proceeds to step S72.

  In step S72, the CPU 2a determines whether or not the CO concentration is equal to or higher than the CO alarm concentration (for example, 300 ppm). If the CO concentration is equal to or higher than the CO alarm concentration, then the fire type is re-determined as smoldering (step S73), and then the process ends. If the CO concentration is not higher than the CO alarm concentration, then the process is terminated.

  If it is determined in step S72 that the CO concentration is equal to or higher than the CO alarm concentration, the reason for re-determining a fire that has been determined as a general fire or a non-fire is as follows.

  Among those determined to be non-fire, any parameter such as Gs, | d | max, Ts, Gco, etc. indicates non-fire depending on various conditions even though a fire has actually occurred. In some cases, it may be determined as non-fire, especially in the case of a smoldering fire. For example, as the smoke concentration Cs increases from Csth1 to Csth2 by many smoldering fire tests, the increase in the CO concentration is very slow, and any of the parameters Gs, | d | max, Ts, Gco Is known to be a non-fire value. It has also been found that the CO concentration when the smoke concentration becomes Csth2 or more is higher than the CO alarm concentration in all the numerous smoldering fire tests.

  On the other hand, in the CO alarm device that detects the CO alarm by detecting the CO concentration, the JIA test regulation 6.2 “Incomplete combustion gas detection part reliably and promptly detects the generated carbon monoxide. "In the case of a smoldering fire, when the smoke concentration becomes Csth2 or more, the CO alarm is already set to CO. It is considered that an alarm has been issued.

  Therefore, even if it is determined in step S71 that there is no fire, if it is determined in step S72 that the CO concentration is greater than or equal to the CO alarm concentration, a fire such as a smoldering fire may have occurred. For this reason, it is determined again as a smoldering fire in step S73. Even if it is determined that the fire is a general fire in step S68 or S70, if the CO concentration is equal to or higher than the CO alarm concentration, there is a high possibility of a full-scale fire. I decided to redo it. Thus, as will be described later, in the smoldering fire determination process, the fire determination smoke threshold value for issuing a fire alarm is a value (for example, 10%) set in the general fire determination process or the non-fire determination process. / M) is set to a lower value (for example, 8% / m), and the fire alarm is issued early. By re-determining it as a smoldering fire, the fire alarm is issued early. Become.

  As described above, the CPU 2a determines fire / non-fire according to the fire / non-fire determination pattern of FIG. 8 in the above-described fire logic determination processing.

  For details of the fire monitoring (alarm monitoring) process in step S4, as shown in FIG. 15, it is first determined whether the fire type is smoldering, general fire or non-fire (step S81). If the fire type is smoldering, then smoldering fire determination processing is performed (step S82), and the processing is then terminated. If the fire type is a general fire, then a general fire determination process is performed (step S83), and then the process ends. If the fire type is non-fire, then non-fire determination processing is performed (step S84), and the processing is then terminated.

  As shown in FIG. 16, the details of the smoldering fire determination process in step S81 are first determined as to whether the alarm state is being monitored or being alarmed (step S101). If it is determined that monitoring is in progress, it is then determined whether or not a long measurement interval tb has elapsed (step S102). If it has elapsed, sensor outputs of the CO sensor 3 and smoke sensor 4 are output every tb seconds. Is converted (step S103), then, based on the sensor outputs of the read CO sensor 3 and smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs is performed and stored in the storage unit 7 (step S104). .

  Next, it is determined whether or not the obtained smoke density Cs exceeds a preset first fire determination smoke threshold, for example, 8% / m (set lower than a typical 10% / m). (Step S105).

  If the smoke concentration Cs does not exceed the first fire determination smoke threshold, then whether or not the smoke concentration Cs falls below a preset smoldering determination end threshold (for example, 2.5% / m) (Step S106), if it is below, then the process is terminated, and if not below, the process returns to step S101.

  If the smoke density Cs exceeds the first fire determination smoke threshold, then the fire alarm flag is set to “1” (step S107). Thereby, the CPU 2a issues an alarm for notifying the occurrence of a fire. That is, the CPU 2a generates an alarm signal and outputs the alarm signal to the alarm output unit 5. The alarm output unit 5 issues an alarm by sounding an alarm sound or displaying an alarm display. Moreover, the external output part 6 sends out the message | telegram etc. for alert | reporting a fire outbreak to an external system, a security center, etc. as needed.

  Next, the CPU 2a sets a continuous check counter to “0” (step S108), and then returns to step S101.

  If it is determined in step S101 that an alarm is being issued, it is then determined whether or not a short measurement interval ta has elapsed (step S109). If it has elapsed, the CO sensor 3 and the smoke sensor 4 are each time ta seconds have elapsed. (Step S110), and then, based on the read sensor outputs of the CO sensor 3 and smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs, respectively, is performed and stored in the storage unit 7 ( Step S111).

  Next, it is determined whether or not the obtained smoke density Cs exceeds the first fire determination smoke threshold (step S112). If the smoke density Cs does not exceed the first fire determination smoke threshold value, then the count of the continuous check counter is incremented by 1 (step S113), and then the count value of the continuous check counter is set in advance ( For example, it is determined whether it is equal to 3 times (step S114). If the count value of the continuous check counter is equal to the preset number of times (for example, 3 times), then the fire alarm flag is set to “0” (step S115). Thereby, CPU2a cancels | releases the alarm which alert | reports a fire occurrence. Next, the CPU 2a sets the alarm state to monitoring (step S116), and then returns to step S101.

  On the other hand, if the smoke density Cs exceeds the first fire determination smoke threshold value in step S112, then the count of the continuous check counter is reset to “0” (step S117), and then the process returns to step S101.

  Thus, in the smoldering fire determination process, if the smoke concentration Cs exceeds the first fire determination smoke threshold, a fire alarm is immediately issued, and the smoke concentration Cs is the first fire determination smoke threshold. If the following is detected three times in succession, the fire alarm is canceled.

  As shown in FIGS. 17 and 18, the details of the general fire determination process in step S83 are first determined as to whether the alarm state is monitoring, before alarm determination, or during alarm determination (step S201). If it is determined that monitoring is in progress, it is then determined whether or not a long measurement interval tb has elapsed (step S202). If it has elapsed, sensor outputs of the CO sensor 3 and smoke sensor 4 are output every tb seconds. (Step S203), and then, based on the sensor outputs of the read CO sensor 3 and smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs is performed and stored in the storage unit 7 (step S204). .

  Next, it is determined whether or not the obtained smoke density Cs exceeds a preset second fire determination smoke threshold (for example, 10% / m) (step S205).

  If the smoke density Cs does not exceed the second fire determination smoke threshold, then whether or not the smoke density Cs falls below a preset general fire determination end threshold (for example, 2.5% / m) (Step S206), if it is below, then the process is terminated, and if not below, the process returns to Step S201.

  If the smoke density Cs exceeds the second fire determination smoke threshold, then the count of the up / down counter is set to “1” (step S207), and then the alarm state is switched before the alarm is confirmed (step S207). S208), and then returns to step S201.

  If it is determined in step S201 that the alarm is not yet confirmed, it is then determined whether or not a short measurement interval ta has passed (step S209). If it has passed, the CO sensor 3 and the smoke sensor are passed every ta seconds. 4 is read (step S210), and then, based on the read sensor outputs of the CO sensor 3 and smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs is performed and stored in the storage unit 7. (Step S211).

  Next, it is determined whether or not the obtained smoke density Cs exceeds the second fire determination smoke threshold (step S212). If the smoke density Cs does not exceed the second fire determination smoke threshold, then the count of the up / down counter is decremented by 1 (step S213), and then the count value of the up / down counter becomes equal to “0”. It is determined whether or not (step S214). If the count value of the up / down counter is equal to “0”, the alarm state is then switched to monitoring (step S215), and then the process returns to step S201. If the count value of the up / down counter is not equal to “0”, the process returns to step S201.

  If the smoke density Cs exceeds the second fire determination smoke threshold value in step S212, then the count of the up / down counter is incremented by 1 (step S216), and then the count value of the up / down counter is preset. It is determined whether or not it has become equal to the count value (for example, “5”) (step S217). If the count value of the up / down counter is equal to “5”, then the count value of the up / down counter is reset to “0” (step S218). Next, the CPU 2a sets a fire alarm flag to “1” (step S219). Thereby, the CPU 2a issues an alarm for notifying the occurrence of a fire. That is, the CPU 2a generates an alarm signal and outputs the alarm signal to the alarm output unit 5. The alarm output unit 5 issues an alarm by sounding an alarm sound or displaying an alarm display. Moreover, the external output part 6 sends out the message | telegram etc. for alert | reporting a fire outbreak to an external system, a security center, etc. as needed. Next, the CPU 2a switches the alarm state to alarming (step S220), and then returns to step 201. On the other hand, if the count value of the up / down counter is not equal to “5”, the process returns to step S201.

  If it is determined in step S201 that an alarm is being issued, it is then determined whether or not a short measurement interval ta has elapsed (step S221), and if it has elapsed, the CO sensor 3 and the smoke sensor 4 every ta seconds have elapsed. (Step S222), and based on the read sensor outputs of the CO sensor 3 and the smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and the smoke concentration Cs, respectively, is performed and stored in the storage unit 7 ( Step S223).

  Next, it is determined whether or not the obtained smoke density Cs exceeds the first fire determination smoke threshold value (step S224). If the smoke density Cs does not exceed the first fire determination smoke threshold, then the count of the up / down counter is incremented by 1 (step S225), and then the count value of the up / down counter becomes equal to “2”. It is determined whether or not (step S226). If the count value of the up / down counter is equal to “2”, then the fire alarm flag is set to “0” (step S227). Thereby, CPU2a cancels | releases the alarm which alert | reports a fire occurrence. Next, the CPU 2a switches the alarm state during monitoring (step S228), and then returns to step S201.

  If the smoke density Cs exceeds the first fire determination smoke threshold value in step S224, it is then determined whether or not the count of the up / down counter is equal to “0” (step S229). If the count of the up / down counter is not equal to “0”, then the count value of the up / down counter is decremented by 1 (step S230), and then the process returns to step S201. If the count of the up / down counter is equal to “0”, the process directly returns to step S201.

  Thus, in the general fire determination process, if the smoke concentration Cs exceeds the second fire determination smoke threshold value five times, a fire alarm is issued and the smoke concentration Cs is the second fire determination smoke threshold value. The fire alarm will be canceled if it falls below twice in succession.

  As shown in FIG. 19, the details of the non-fire determination process in step S84 are first determined as to whether the alarm state is monitoring, before alarm confirmation, or during alarming (step S301). If it is determined that monitoring is in progress, it is then determined whether or not a long measurement interval tb has elapsed (step S302). If it has elapsed, sensor outputs of the CO sensor 3 and smoke sensor 4 are output every tb seconds. Is converted (step S303), and then conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs is performed based on the read sensor outputs of the CO sensor 3 and smoke sensor 4, respectively, and stored in the storage unit 7 (step S304). .

  Next, it is determined whether or not the obtained smoke density Cs exceeds a preset second fire determination smoke threshold (for example, 10% / m) (step S305).

  If the smoke density Cs does not exceed the second fire determination smoke threshold value, then whether or not the smoke density Cs falls below a preset non-fire determination end threshold value (for example, 2.5% / m) (Step S306), if it is below, then the process is terminated, and if not below, the process returns to step S301.

  If the smoke density Cs exceeds the second fire determination smoke threshold, then the count of the continuous check counter is set to “1” (step S307), and then the alarm state is switched before the alarm is confirmed (step S307). S308), and then returns to step S201.

  If it is determined in step S301 that the alarm has not been confirmed, it is then determined whether or not a short measurement interval ta has elapsed (step S309). If it has elapsed, the CO sensor 3 and the smoke sensor are analyzed every ta seconds. 4 is read (step S310), and then, based on the read sensor outputs of the CO sensor 3 and smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and smoke concentration Cs is performed and stored in the storage unit 7. (Step S311).

  Next, it is determined whether or not the obtained smoke density Cs exceeds the second fire determination smoke threshold (step S312). If the smoke density Cs does not exceed the second fire determination smoke threshold value, then the count of the continuous check counter is reset to “0” (step S313), and then the alarm state is set to monitoring (step S313). S314), and then returns to step S301.

  If the smoke concentration Cs exceeds the second fire determination smoke threshold, then the count of the continuous check counter is incremented by 1 (step S315), and then the count value of the continuous check counter is set in advance ( For example, it is determined whether or not it is equal to 20 times (step S316). If the count value of the continuous check counter is not equal to the preset number of times (for example, 20 times), the process returns to step S301. If the count value of the continuous check counter is equal to a preset number of times (for example, 20 times), then the fire alarm flag is set to “1” (step S317). Thereby, the CPU 2a issues an alarm for notifying the occurrence of a fire. That is, the CPU 2a generates an alarm signal and outputs the alarm signal to the alarm output unit 5. The alarm output unit 5 issues an alarm by sounding an alarm sound or displaying an alarm display. Moreover, the external output part 6 sends out the message | telegram etc. for alert | reporting a fire outbreak to an external system, a security center, etc. as needed. Next, the CPU 2a switches the alarm state to alarming (step S318), and then returns to step 301.

  If it is determined in step S301 that an alarm is being issued, it is then determined whether or not a short measurement interval ta has elapsed (step S319). If it has elapsed, the CO sensor 3 and the smoke sensor 4 are analyzed every ta seconds. (Step S320), and based on the read sensor outputs of the CO sensor 3 and the smoke sensor 4, conversion calculation processing for obtaining the CO concentration Cco and the smoke concentration Cs, respectively, is performed and stored in the storage unit 7 ( Step S321).

  Next, it is determined whether or not the obtained smoke density Cs exceeds the second fire determination smoke threshold (step S322). If the smoke density Cs does not exceed the second fire determination smoke threshold, then the fire alarm flag is set to “0” (step S323). Thereby, CPU2a cancels | releases the alarm which alert | reports a fire occurrence. Next, the CPU 2a switches the alarm state during monitoring (step S324), and then returns to step S301. If the smoke density Cs exceeds the first fire determination smoke threshold, then the process returns to step S301.

  Thus, in the non-fire determination process, if the smoke concentration Cs exceeds the second fire determination smoke threshold value 20 times in succession, a fire alarm is issued and the smoke concentration Cs is the second fire determination smoke. If it falls below the threshold value once, the fire alarm is immediately canceled.

  In this way, in the non-fire determination process, if the smoke concentration Cs exceeds the second fire determination smoke threshold value 20 times continuously (that is, after the delay time corresponding to 20 consecutive times has elapsed), a fire occurs. If it does not exceed 20 times continuously, it is determined as non-fire and no fire alarm is issued. Therefore, not only false alarms during non-fire based on generation of temporary CO and smoke such as cigarettes, but also false alarms during non-fire based on CO and smoke generated during cooking are reduced. become.

  As is clear from the above description, in the flowcharts of FIGS. 11 to 19, step S37 corresponds to the elapsed time measuring means in the claims, step S51 corresponds to the calculating means in the claims, and step S53 is the claims. Step S55 corresponds to the smoke density difference determination means in the claims, step S57 corresponds to the elapsed time determination means in the claims, and step S59 corresponds to the CO concentration inclination determination means in the claims. Steps S64, 66, 68, and 70 correspond to the fire determination means in the claims, and step S71 corresponds to the non-fire determination means in the claims. Further, step S105 corresponds to the first fire determination means in the claims, step S212 corresponds to the second fire determination means in the claims, and steps S107 and 219 correspond to the notification means in the claims. ing. Steps S15 to S18 and S38 to S42 correspond to the determination operation stop means in the claims. Step S316 corresponds to the delay time setting means in the claims, step S312 corresponds to the third fire determination means in the claims, and step S317 corresponds to the notification means in the claims.

  As described above, according to the present invention, it is possible to effectively distinguish between a fire and a non-fire according to the degree of increase in smoke concentration, and it is possible to reliably notify a fire. In addition, the number of operations of the fire / non-fire discrimination logic due to external noise can be suppressed, the operation of the logic that is not necessary originally can be limited, and the power consumption of the battery can be suppressed.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various deformation | transformation and application are possible.

  For example, the data of the smoke density Cs may be an instantaneous value or a moving average value.

  Further, if it is determined in step S72 in FIG. 14 that the CO concentration is equal to or higher than the CO alarm concentration and it is determined again as a smoldering fire in step S73, the first in steps S105 and S112 in FIG. The fire judgment smoke threshold may be switched to a lower value (for example, 7% / m) to make it easier to generate a fire alarm.

  In the above-described embodiment, the case where the present invention is applied to a fire alarm device has been described. However, the present invention is not limited to this, and the present invention can also be applied to a combined alarm device having both functions of a CO alarm device and a fire alarm device.

It is a block diagram which shows the structure of the fire alarm using the fire / non-fire discrimination apparatus which concerns on embodiment of this invention. It is a figure which shows a cooking test result. It is a figure which shows a fire test result. It is a figure which shows roughly the cooking test room which imitated the kitchen of the general house. It is a figure which shows a fire test chamber schematically. It is a figure for demonstrating the calculation method of smoke density inclination Gs and smoke density difference maximum value | d | max. (A) is an example of a graph representing the measured value of the smoke concentration and the primary expression obtained as described above from the measured value, and (b) is an example of a graph representing the density difference between the measured value and the primary expression. FIG. It is a figure which shows a fire / non-fire discrimination pattern. It is a figure for demonstrating an example of external noise. It is a figure explaining the timing of external noise and logic invalidity. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG. It is a flowchart which shows the detailed operation | movement of the fire detection process of the fire alarm device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fire alarm device 2 Microcomputer 2a CPU (Calculation means, smoke concentration inclination determination means, CO concentration inclination determination means, CO concentration determination means, elapsed time measurement means, elapsed time determination means, fire determination means, non-fire determination means, first Fire determination means, second fire determination means, third fire determination means, delay time setting means, part of notification means, discrimination operation stop means)
3 CO sensor 4 Smoke sensor 5 Alarm output part (part of the notification means)
7 Memory part

Claims (3)

A smoke sensor for detecting the smoke density, a CO sensor for detecting the CO density, and a smoke density detected at each predetermined detection timing by the smoke sensor is higher than the first set smoke density and the first set smoke density. Based on a plurality of measured data of the smoke density that continuously fluctuates between the set second smoke densities, a slope of a linear expression approximated linearly is calculated as a smoke density slope Gs, and the smoke density The maximum value of the difference between the actually measured data of the smoke and the smoke density value represented by the linear expression is calculated as the smoke density difference maximum value | d | max, and a plurality of values detected at the same time as the measured data of the smoke density Cs are calculated. Based on the actual measurement data of the CO concentration, the calculating means for calculating the slope of the linear expression approximated linearly as the CO concentration gradient Gco, and the smoke concentration gradient Gs is less than a preset smoke concentration gradient threshold value. Smoke density to determine whether or not Determination means, smoke density difference determination means for determining whether or not the smoke density difference maximum value | d | max is less than a preset smoke density difference threshold value, and the smoke density is the first value. The elapsed time measuring means for measuring the elapsed time Ts from the set smoke density to the second set smoke density, and the elapsed time Ts measured by the elapsed time measuring means is a preset elapsed time threshold. Elapsed time determining means for determining whether or not the value exceeds a value, CO concentration gradient determining means for determining whether or not the CO concentration gradient Gco exceeds a preset CO concentration gradient threshold value, and A smoke determination means for determining a fire according to a combination of determination results of the smoke concentration gradient determination means, the smoke concentration difference determination means, the elapsed time determination means and the CO concentration gradient determination means; and the smoke concentration gradient determination means , Non-fire determination for determining non-fire when the determination results of the smoke concentration difference determination means, the elapsed time determination means, and the CO concentration gradient determination means do not correspond to the combination for determining the fire A fire / non-fire discrimination device that distinguishes between fire and non-fire,
When the number of times that the smoke density is less than the first set smoke density without exceeding the second set smoke density after the smoke density exceeds the first set smoke density becomes a predetermined number of times or more within a predetermined period In addition, the fire / non-fire discrimination device further comprises a discrimination operation stop means for stopping the fire / non-fire discrimination operation. A fire alarm using the fire / non-fire discrimination device according to claim 1,
First fire determination means for determining whether or not the smoke concentration exceeds a predetermined first fire determination smoke threshold when the fire / non-fire determination device determines that a fire has occurred;
When the discrimination operation of the fire / non-fire is stopped by the discrimination operation stop means, the smoke concentration is higher than the first fire judgment smoke threshold and exceeds a predetermined second fire judgment smoke threshold. A second fire determination means for determining whether or not
When the first fire determination means determines that the smoke concentration exceeds the first fire determination smoke threshold, or the second fire determination means determines that the smoke concentration is the second fire determination smoke. If it is determined that the threshold value has been exceeded, a notification means for notifying a fire alarm;
A fire alarm device comprising: In the fire alarm according to claim 2,
A delay time setting means for setting a predetermined delay time when it is determined as a non-fire by the fire / non-fire determination device;
And third fire determination means for determining whether or not the smoke concentration has exceeded the second fire determination smoke threshold over the predetermined delay time set by the delay time setting means. ,
The notification means further notifies a fire alarm when the third fire determination means determines that the smoke concentration exceeds the second fire determination smoke threshold value. .

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