JP2602326B2 - Automatic ventilation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an automatic ventilator, and in particular, determines the start of cooking, automatically drives a ventilation fan, and generates hot air generated during cooking.
The present invention relates to a control system of an automatic ventilation device that detects contaminated air such as smoke, odor, gas, and the like, and automatically controls the ventilation amount (air volume) of a ventilation fan based on the detected value.

[Conventional technology]

As a conventional automatic ventilator, there is an automatic ventilator that detects a flame based on the presence or absence of ultraviolet rays and drives a ventilation fan for a predetermined time as described in Japanese Utility Model Application Laid-Open No. 62-95216. Also, JP-A-56-1423
As described in Japanese Patent Publication No. 33, there is an apparatus that stores a sensor output signal for a long time and compares it with a new output signal to detect a change in the sensor output signal to drive a ventilation fan. Further, as described in Japanese Utility Model Application Laid-Open No. 62-67134, there is a device that compares an output signal of a temperature sensor and an output signal of a gas sensor and drives a ventilation fan with a larger control amount (high-speed rotation side).

A technique of storing the output signal of a sensor for a long time, comparing the output signal with a new output signal, and automatically controlling the output signal according to a change in the output signal of the sensor is disclosed in JP-A-54-2526 and JP-A-52-59347. No., etc.

[Problems to be solved by the invention]

In the above-described prior art, a sensor is used, and a ventilation fan is driven by an output signal from the sensor. However, no consideration has been given to the deterioration over time of the detection capability or the detection accuracy of the sensor used. Further, the prior art described above is
Immediately cope with fire extinguishing (fire) caused by overheating of cooked items and cooking extinguishing of cooked items such as gas cookers (heating devices). Such considerations have not been made and there are functional issues.

SUMMARY OF THE INVENTION It is an object of the present invention to be able to start operation almost simultaneously with the start of cooking, to detect and discharge contaminated air such as hot air, smoke, odor, and gas generated at the time of cooking, and to measure the detection ability of a sensor used over time. It is an object of the present invention to provide an automatic ventilation device capable of self-detecting deterioration, determining the life of a sensor before malfunction occurs, and displaying the life of the sensor by a display and an alarm. It is still another object of the present invention to provide an automatic ventilation device having a function of preventing loss of time-lapse deterioration detection data due to a power failure or the like.

Another object of the present invention is to be able to start operation almost simultaneously with the start of cooking, detect and discharge contaminated air such as hot air, smoke, odor, and gas generated during cooking, and to extinguish flames and reduce gas fired power. It is an object of the present invention to provide an automatic ventilation device capable of switching a ventilation amount in order to quickly cope with an abnormal situation such as a raw gas leak due to an incomplete closing of an adjustment operation unit or a fire due to overheating. It is still another object of the present invention to provide an automatic ventilator that gives notification by display and alarm when an abnormal situation occurs and when the sensor is in service.

[Means for solving the problem]

To achieve the above object, an ultraviolet sensor for detecting radiation emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, and a fan capable of discharging contaminated air, A control circuit for processing the output signal of each of the sensors to control the fan motor; and a means for detecting self-aging of the sensor and a means for informing the service life of the sensor. as a means, each time reaching the time degradation detection condition is satisfied when a predetermined operating temperature the rated operating temperature of the gas sensor: T ₀ and this lower predetermined set operating temperature is changed to T _1, the operating temperature T ₀ and the resistance value of the gas sensor in the T ₁ R _T0 and deterioration determination index from R _T1: while calculating and storing the _{P n = R T1 / R T0} , the initial value of the deterioration determination index: moth with P ₀ Computing the change Q _n = P _n / P ₀ of the degradation determination index from the sensor initial use, further the deterioration with time self-correction means of the gas sensor, the change in the deterioration determination index: a plurality of contaminated air commensurate with Qn It has a life level notifying means for setting a detection level, displaying a life, and issuing a warning or a synthesized voice.

Also, an ultraviolet sensor for detecting ultraviolet rays emitted from the flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and output signals of the sensors. And a control circuit for controlling the fan motor, and a means for detecting self-aging of the sensor and a means for informing the life of the sensor. A device which has a life notifying means for accumulating and storing the time during which the flame is detected from the start of use and for notifying by a life display and an alarm or a synthesized voice when the accumulated time reaches a predetermined time. It is.

Further, the deterioration determination index when the gas sensor used: the change in P _n and the deterioration determination index: as Q _n and means for storing a detection level after the self-correction of the contaminated air detection level, a non-volatile memory: Backup by EEPROM or battery means It is good to use any of the CMOS RAMs having.

Further, it is preferable that the predetermined time-dependent deterioration detection condition of the gas sensor is such that the fluctuation of the output signal of each sensor is equal to or less than a predetermined value and continues for a predetermined time.

Also, an ultraviolet sensor for detecting ultraviolet rays emitted from the flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and output signals of the sensors. , A control circuit for controlling the fan motor, a raw gas leak informing means, an abnormal temperature rise informing means, a time-dependent deterioration self-detection means and a sensor life informing means of the sensor, and the time-dependent deterioration of the sensor. As the self-detecting means and the sensor life informing means, every time a predetermined time deterioration detection condition is met, the operating temperature of the gas sensor is rated operating temperature: T
₀ and this lower predetermined set operating temperature: T ₁ is changed, the operating temperature T ₀ and the resistance value of the gas sensor in the T ₁ R _T0
Calculates and stores a deterioration determination index from P _T and R _T1 : P _n = R _T1 / R _T0 , and uses the initial value of the deterioration determination index: P ₀ to change the deterioration determination index from the initial use of the gas sensor: Q _n = Calculating P _n / P ₀ , furthermore, as a means for self-correction of deterioration of the gas sensor over time, change of the deterioration determination index: setting a plurality of contaminated air detection levels commensurate with Qn, further, life display, and alarm Alternatively, it has a life informing means for informing by a synthetic voice.

Also, an ultraviolet sensor for detecting ultraviolet rays emitted from the flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and output signals of the sensors. , A control circuit for controlling the fan motor, a raw gas leak informing means, an abnormal temperature rise informing means, a time-dependent deterioration self-detection means and a sensor life informing means of the sensor, and the time-dependent deterioration of the sensor. As the self-detecting means and the sensor life informing means, the time during which the ultraviolet ray sensor detects the flame is accumulated and stored from the start of use, and when the accumulated time reaches a predetermined time, a life display and It has a service life informing means for informing by alarm or synthesized voice.

As means for accumulating and storing the time of detecting the flame of the ultraviolet sensor, a nonvolatile memory: an EEPROM or a CMOS RAM having a backup means by a battery
It is good to use either of them.

Also, an ultraviolet sensor for detecting ultraviolet rays emitted from the flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and output signals of the sensors. And a control circuit for controlling the fan motor to process the raw gas leak, a raw gas leak notification unit, an abnormal temperature rise notification unit, a self-deterioration deterioration detection unit for the sensor, and a sensor life notification unit. As a means, when the level of the output signal of the ultraviolet sensor falls below a first predetermined value and the amount of change of the output signal of the gas sensor increases above a second predetermined value, a live gas leak display and an alarm or synthesis are performed. It has a means for giving notification by voice.

Also, an ultraviolet sensor for detecting ultraviolet rays emitted from the flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and output signals of the sensors. And a control circuit for controlling the fan motor to process the fan motor, a raw gas leak notification unit, an abnormal temperature rise notification unit, a self-detection unit for detecting deterioration with time of the sensor, and a sensor life notification unit. As means, when the level of the output signal of the ultraviolet sensor is higher than a third predetermined value and the amount of change in the output signal of the temperature sensor is higher than a fourth predetermined value, an abnormal temperature rise display and an alarm are issued. Alternatively, it has a means for performing notification by a synthetic voice.

At this time, when the level of the output signal of the ultraviolet sensor drops below a first predetermined value and the amount of change in the output signal of the gas sensor increases above a second predetermined value, the control circuit sets the fan Controlling the fan motor so as to maximize the amount of ventilation caused by the air conditioner, the level of the output signal of the ultraviolet sensor increases from a third predetermined value, and the amount of change in the output signal of the temperature sensor changes to a fourth predetermined value. When the value exceeds the value, the fan motor may be controlled so that the ventilation amount of the fan is set to zero.

[Operation] The ultraviolet sensor detects ultraviolet rays emitted from the flame of a cooking appliance such as a gas stove, and outputs an ultraviolet detection signal corresponding to the level of the intensity of the ultraviolet rays to the control circuit. The gas sensor detects contaminated air and outputs a gas detection signal corresponding to the concentration level to the control circuit. The temperature sensor detects the temperature of the hot air and outputs a temperature detection signal corresponding to the temperature level to the control path.

The control circuit obtains the generation of ultraviolet rays accompanying the ignition from the ultraviolet ray detection signal, instantaneously determines the start of cooking, and drives the fan motor (and the fan). Further, the control circuit determines the presence or absence and the density of the contaminated air and hot air using the level change of the gas detection signal and the level change of the temperature detection signal, and responds to the rise in the concentration of the contaminated air and the temperature of the hot air. Drive the motor. Furthermore, it is necessary to control the fan motor with the same amount of change in the gas sensor output as the initial setting value for a long period of time to determine the presence or absence and concentration of the contaminated air, and to examine the degree of deterioration of the gas sensor over time in order to perform normal ventilation. Therefore, in order to examine how much deteriorated gas sensor, the gas sensor is varied to a lower operating temperatures T ₁ then rated operating temperature T ₀ of the operating temperature, deterioration wins determined from the resistance value of the gas sensor in each of the operating temperature Index: PR _T1 / R _T0 is obtained, and the deterioration judgment index in the early stage of gas sensor use: Change from Po: Qn = Pn
By calculating / Po, the degree of deterioration of the gas sensor is known from this Qn, and the detection level of contaminated air is reset according to the degree of deterioration, and self-correction of the deterioration with time of the gas sensor is performed. The result of the self-correction (detection level) is stored in a nonvolatile memory (for example, EERPOM) provided in the control circuit. When the self-correction cannot finally be performed due to the deterioration with time, a message indicating that the gas sensor has reached the end of its service life is displayed, and an alarm or a synthesized voice is issued.

The deterioration with time of the ultraviolet sensor that detects the ignition of the cooking utensil is obtained by accumulating the time during which the ultraviolet sensor detects the flame from the start of use and storing the accumulated time. When the accumulated time reaches a predetermined time, a life display and a warning or a synthesized voice is issued.

In addition, since the deterioration judgment index of the gas sensor: Po, and the change of the deterioration judgment index: Qn, the polluted air detection level after self-correction with time deterioration, and the flame detection integrated time of the ultraviolet sensor are stored in the nonvolatile memory, There is no malfunction even if a power failure occurs.

Further, when the ultraviolet detection signal is lower than the first predetermined value and the level change of the gas detection signal is higher than the second predetermined value, the control circuit may cause the flame to extinguish or the gas-fired power adjustment operation unit to be incomplete. It is determined that a raw gas leak has occurred due to an improper closure; an accident such as a fire occurs when the ultraviolet detection signal increases above a third predetermined value and the level change of the temperature detection signal increases above a fourth predetermined value. Judge that
The fan motor is controlled according to each situation.

Thereby, the fan motor and the fan start operating almost at the same time as the start of cooking, operate according to the level of hot air or contaminated air, and switch the ventilation amount immediately in response to an abnormal situation, thereby improving the function. .

Further, the control circuit gives a notification by display, alarm or synthesized voice when an abnormal situation occurs and when the sensor has reached the end of its life, so that the user can prevent the accident from spreading.

〔Example〕

Before describing the embodiments, basic matters according to the present invention will be described.

The present inventors have conducted various studies on the performance of the gas sensor for detecting the degree of contamination of the contaminated air with respect to the deterioration with time.As a result, when the performance of the gas sensor deteriorates, the operating temperature of the gas sensor is set to the rated operating temperature: T ₀ and lower operating temperature T ₁ is changed, the operating temperature resistance of the gas sensor in T ₀ and T _1: from R _T0 and R _T1, when obtaining the R _T1 / R _T0, the ratio of the resistance value with respect to the respective operating temperature: the value of P = R _T1 / R _T0 are newly found to come reduced compared to the gas sensor using the initial. This phenomenon will be described below with reference to FIGS. 3, 4, and 5.

FIG. 3 shows the rated operating temperature of a semiconductor gas sensor having a reducing gas detecting gas-sensitive part and a heater for heating the gas-sensitive part in a normal air atmosphere at the operating temperature T ₀ and lower operating temperature T ₁ . FIG. 4 is a characteristic diagram showing resistance values at the time of FIG. In the figure, the characteristic 41 is the characteristic at the beginning of use of the gas sensor,
42, 43, 44 and 45 are characteristics in the case where the performance has deteriorated with time due to long-term use. The ratio of the resistance of the gas sensor at each operating temperature of T ₀ and T ₁ : P = R _T1 / R _T0 decreases as the performance deteriorates with time. Therefore, P is referred to as a deterioration determination index.

Next, FIG. 4 shows a change in the sensitivity of contamination detection due to the deterioration of the gas sensor with time. The resistance of the gas sensor in a normal air atmosphere and the resistance in a polluted atmosphere (for example, hydrogen gas: 4
In 0 ppm: ratio of resistance of gas sensor at a pollutant atmosphere concentration equivalent to 10 to 15 cigarettes smoked in a 6 tatami room): K =
When R _AIR / R _H2 is the contamination detection sensitivity of the gas sensor,
It indicates the change in the contamination detection sensitivity due to aging, and the sensitivity increases with aging. FIG. 5 is a characteristic diagram showing the relationship between the above-mentioned contamination detection sensitivity due to the deterioration of the gas sensor over time: K = R _AIR / R _H2 and the change of the deterioration judgment index: Qn = Pn / Po. A good correlation is shown except when the initial performance degradation is small. Degradation judgment index P of gas sensor performance and change of deterioration judgment index: Qn = Pn /
Po is measured by changing the gas sensor from the rated operating temperature: T ₀ (° C) to a lower operating temperature: T ₁ (° C).
Temperature at this time: T ₁ (° C) is 1/2 of rated operating temperature: Tc (° C)
It is desirable that the temperature be 7/8 or less. T ₁ <12T ₀
In the case of, it takes time to change the operating temperature to T ₁ (° C) and to obtain stable gas sensor characteristics (R _T1 ).
Not practical. When T ₁ > 7 / 8T ₀ , the value of the deterioration determination index: P = R _T1 / R _T0 becomes small, and the accuracy of the deterioration detection performance decreases, which is not desirable.

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

FIG. 2 is an example of a structural view of the automatic ventilation device of the present invention. FIG. 2 (a) is a front view in which the front cover 29 of the main body 20 of the automatic ventilation device is removed, and a part is cut away. FIG. 2 (b) shows the main body 20 of the automatic ventilation device.
It is the side view which notched a part of. The illustrated automatic ventilation device is installed above the cooking place and near the ceiling.

In FIG. 2, 1 is a gas sensor for detecting polluted air (hereinafter, referred to as contaminated air), 2 is a temperature sensor for detecting hot air, and 3 is a UV sensor for detecting ultraviolet rays emitted from a flame of a gas stove (not shown). An ultraviolet ray detecting tube (ultraviolet ray sensor); 24, a fan for discharging contaminated air; and 25, a fan motor for driving the fan 24. Hereinafter, the fan 24 and the fan motor 25 are collectively referred to as a ventilation fan.

26 is a grease filter that captures and removes particulate matter such as oil mist from contaminated air, 27 is a control circuit that controls the ventilation operation of ventilation fans (24, 25), and 12 is the extinguishing of the gas stove flame or gas-fired power adjustment An abnormality notification device for notifying abnormal situations such as the occurrence of raw gas leakage due to incomplete closing of the operation unit and the occurrence of fire due to overheating, 13 is the service life of the gas sensor (1) and ultraviolet sensor (3). The sensor life informing devices 28 and 28 'for informing are lamp houses for storing lamps (not shown) for illuminating the lower part of the main body 20 . 29 is the cover provided to increase the capture efficiency of contaminated air, 30 is left on the ceiling surface (not shown),
A curtain plate that guides contaminated air to ventilation fans (24, 25), 31 is a fan 24
This is an exhaust port for discharging contaminated air taken in by the air to the outside.

When the gas is ignited by a gas stove provided below the main body 20 and a flame is generated, the ultraviolet ray detecting tube 3 detects the ultraviolet ray radiated from the flame and sends a signal indicating the presence or absence (and a signal of the intensity level) to a control circuit. Supply 27. The control circuit 27 receives the signal from the ultraviolet ray detecting tube 3 and drives the ventilation fans (24, 25).

As a result, contaminated air such as hot air and smoke generated by the flame of the gas stove is discharged to the main body of the automatic ventilation system installed above.
Guided to 20. And mainly, the contaminated air is
Collected by the fan through the grease filter 26
Inhaled to 24. At this time, a part of the contaminated air whose particle components have been captured and removed by the grease filter 26 is sucked into the fan 24 after passing through a place where the gas sensor (reducing gas sensor) 1 and the temperature sensor 2 are installed.

The temperature sensor 2 detects the temperature of the contaminated air and supplies a signal of the temperature level to the control circuit 27. Similarly, the gas sensor 1 detects smoke, odor, gas, etc. in the contaminated air,
A signal corresponding to the level is supplied to the control circuit 27. The control circuit 27 detects the contaminated air from the signals supplied from the temperature sensor 2 and the gas sensor 1 and continuously drives the ventilation fan. The contaminated air sucked by the fan 24 is discharged to the outside through the exhaust port 31.

As shown, the gas sensor 1 and the temperature sensor 2 are installed behind the grease filter 26 so as to maintain the detection performance over a long period of time and maintain reliability. For the same reason, the ultraviolet detecting tube 3 is housed in a case 21 having a closed structure except for the surface facing the gas stove, and is installed at a position farthest from the flow path of the contaminated air.

Next, the configuration of the control system in the automatic ventilation device of the present invention will be described with reference to the block diagram of FIG.

In FIG. 1, reference numerals 1 to 3 denote the sensors described in FIG. 2, respectively. In particular, 1 has a gas-sensitive part for detecting a reducing gas and a heater part for heating the gas-sensitive part. A semiconductor type reducing gas sensor (gas sensor) 3 is an ultraviolet detecting tube having a built-in pulse generator (not shown), which converts the intensity of the incident ultraviolet light into the number of pulses per unit time and outputs the result. It is. Reference numeral 7 denotes a microcomputer (hereinafter abbreviated as a microcomputer). Reference numeral 4 denotes a pulse counter which counts pulses output from the ultraviolet detecting tube 3 after being reset by the microcomputer 7 and supplies the count value to the microcomputer 7.

Reference numeral 5 denotes a multiplexer (analog switch) that switches and outputs the output of the gas sensor 1 and the output of the temperature sensor 2 according to a switching signal from the microcomputer 7. 6
Converts the output of multiplexer 5 to a digital signal,
An A / D converter that supplies this digital signal to the microcomputer 7. Reference numeral 8 denotes a RAM (random access memory) in which data is recorded by the microcomputer 7 and the data is read.
It is. Reference numeral 9 denotes a ROM (read only memory) from which constant data stored in advance is read by the microcomputer 7. Ten
In the case where a power failure occurs, data such as a sensor deterioration determination index of the gas sensor 1 calculated by the microcomputer 7, a polluted air detection level reset by the deterioration self-correction, and an integrated time when the ultraviolet sensor 3 detects ultraviolet light are recorded. Non-volatile memory (EEPROM or battery backed up) that can be read without data loss
CMOS RAM).

Reference numeral 11 denotes a motor control circuit that controls the number of revolutions of the fan motor 25 in accordance with the output signal of the microcomputer 7. The fan 24 shown in FIG. 2 changes the ventilation volume by changing the rotation speed of the fan motor 25. Reference numeral 12 denotes an abnormality notification device that uses a lamp display and an alarm or a synthesized voice to notify an abnormality such as a raw gas leak or a fire. 14 the operating temperature of the gas sensor in accordance with the output signal of the microcomputer 7 during aging deterioration detection of the gas sensor 1, the rated operating temperature: T ₀ lower than this from the operating _{temperature: T 1 (1 / 2T 0} ≦ T 1 ≦ 7 / 8T _{This is} a sensor operating temperature control circuit for changing the temperature to ₀ ). Reference numeral 13 denotes a sensor for displaying a sensor life and issuing an alarm or synthesizing a voice based on an output signal from the microcomputer 7 when the microcomputer 7 determines that the gas sensor 1 and the ultraviolet sensor 3 are near the end of their life due to aging. It is a life notification device. The control circuit 27 described with reference to FIG.
Pulse counter 4, multiplexer 5, A / D converter 6, RAM8, RO
M9, a nonvolatile memory 10, a motor control circuit 11, and a gas sensor operating temperature control circuit 14.

Next, the operation of the control system of the present embodiment shown in FIGS. 1 and 2 will be described with reference to the flowcharts of FIGS.

6 and 7 are diagrams showing the algorithm of the microcomputer 7. FIG. Now, it is assumed that the user connects the automatic ventilation device of the present invention to a power supply. The microcomputer 7 starts operating at the same time when the power is turned on. This point is called START1 in Fig. 6.
Shown as 40. Thereafter, the microcomputer 7 sets the pulse counter 4
Reset to prepare for UV detection (step 14
1).

Then, the microcomputer 7 controls the multiplexer 5 to
The output signal of the gas sensor 1 and the output signal of the temperature sensor 2 are read via the A / D converter 6 (step 14).
2). The microcomputer 7 stores the read output signal of the gas sensor 1 in the RAM 8 as a gas sensor output (concentration) reference value SENφ. Similarly, the output signal of the temperature sensor 2 is stored in the RAM 8 as the temperature reference value THφ (step 143).
Thereafter, similarly to step 141, the output signal of the gas sensor and the output signal of the temperature sensor 2 are read again. The output signal of the gas sensor 1 at this time is stored in the RAM 8 as the gas sensor output SEN1. The output signal of the temperature sensor 2 is stored in the RAM 8 as a measured temperature value TH1 (step 1).
44). Then, the microcomputer 7 sets the gas sensor output reference value SEN
The output ratio SC between φ and the gas sensor output value SEN1 is calculated from SEN1 / SENφ. This ratio SC is also stored in the RAM 8. further,
The temperature difference TC between the measured temperature value TH1 and the temperature reference value THφ is expressed as TH1−
Calculated by THφ. The microcomputer 7 stores the temperature difference TC in the RAM 8
(Step 145).

Next, it is determined whether a predetermined time TM3 has elapsed (step 146). Here, the time TM3 indicates a cycle of the timing of detecting the ultraviolet rays. If the time TM3 has elapsed, the microcomputer 7 resets the pulse counter 4 as shown in step 147.

Next, the output of the pulse counter 4 is read, and the read ultraviolet ray measurement value PC is stored in the RAM 8 (step 14).
8). Here, when the ultraviolet ray measurement value PC is equal to or larger than a predetermined set value N, the ultraviolet ray detection tube 3 detects the ultraviolet ray radiated from the flame of the gas stove, and outputs a pulse output based on the detection result to the pulse counter 4. Indicates that it was output.

Note that the microcomputer 7 regards the time when the gas stove is ignited (ignited) as the start time of cooking, and proceeds with the process. If the ultraviolet ray measurement value PC is less than the set value N, the microcomputer 7 determines that the gas stove is in an unused state (step 155 in FIG. 7).

When the gas stove is not used, whether the ventilation fan is stopped, that is, the microcomputer 7
It is determined whether or not 25 is stopped through the motor control circuit 11 (step 156 in FIG. 7). When the ventilation fan is stopped, the process proceeds to step 157, and when the ventilation fan is driven, the process proceeds to step 159.

In step 157, it is determined whether there is hot air, smoke, odor, gas or the like generated by cooking. Specifically, the steps
The output ratio SC calculated in 145 is compared with the output ratio reference value SCD stored in the ROM 9 in advance. In addition, the temperature difference TC and the ROM
9 is compared with the temperature difference reference value THD1. Here, if SC <SCD and TC ≦ THD1, hot air, smoke, smell,
It is determined that there is no generation of gas or the like, and the process proceeds to step 162 (renewal of the reference value). On the other hand, this SC <SCD and T
If the condition of C ≦ THD1 is not satisfied, it is determined that hot air, smoke, odor, gas, and the like have been generated by cooking, and the flow proceeds to the determination processing of step 159. Step 1
If the ultraviolet ray measurement value PC satisfies PC ≧ N at 55, it is determined that the gas stove is ignited (ignited) and cooking has been started, and the ignition detection time integration is started by the timer built in the microcomputer 7 (step 158). Move to 159. Step 15
In step 9, the output ratio SC of the gas sensor is compared with the output ratio reference value SCD. Further, the temperature difference TC stored in the ROM 9 in advance is compared with the temperature difference reference value THD2.

As a result of the comparison, if SC ≧ SCD or TC ≧ THD2,
The microcomputer 7 drives the ventilation fan (step 160). If the result of the comparison does not satisfy the above condition, the ventilation fan is driven for a predetermined (designated) time (step 161).

Next, after the reference value is updated in step 162, the process proceeds to ultraviolet sensor life detection (step 163). Then, in step 164, a steady operation mode for detecting air pollution and a mode for detecting deterioration of the gas sensor are selected. The determination value S is for determining the cycle of the deterioration detection mode,
Now, if N ≧ S in step 164, N is initialized to 0 (step 165), and then the deterioration detection of the gas sensor (step 1)
Go to 66). After any one of the processes shown in steps 160, 161 and 166, that is, one of the processes of driving the ventilation fan, driving the ventilation fan for the designated time, detecting the life of the ultraviolet sensor, and detecting the deterioration of the gas sensor, terminates the automatic operation (step 167). Unless the switch (not shown) is pressed, the process returns to step 144 in FIG. 6, and the processes from step 144 onward are repeated.

Next, the updating of the reference value in step 162 in FIG. 7 will be described with reference to the flowchart in FIG.

The update of the reference value (step 162) is a process for preventing a malfunction due to an environmental change other than cooking. The cycle of the update process is determined by a predetermined time TM1, as shown in step 170. When the time TM1 has elapsed, the microcomputer 7
The gas sensor output value SEN1 stored in the ROM 8 is reset as the gas sensor output reference value SENφ, and the new SENφ is stored in the RAM8.
To memorize. Similarly, the microcomputer 7 calculates the temperature measurement value TH1
Is stored in the RAM 8 as a new temperature reference value THφ (step 171). As described above, in updating the reference value (step 162 in FIG. 7), the gas sensor output reference value SENφ and the temperature reference value THφ are updated. As described above, updating the reference values SENφ and THφ for controlling has an advantage in that a long-period input signal detected by each sensor (1, 2) can be removed.

Next, the driving of the ventilation fan in step 160 in FIG. 7 will be described with reference to the flowchart in FIG.

First, according to the output ratio SC based on the gas sensor output reference value SENφ, a value for determining a ventilation amount (air volume), that is, a control amount FS1 of the ventilation fan is calculated (step 172). Similarly, the control amount FS2 of the ventilation fan is calculated according to the temperature difference TC (step 173). These control variables FS1, FS2
Is calculated based on the specifications of the fan and the fan motor 25 and the control function of the motor control circuit 11 by a preset design equation or an experimental equation.

The microcomputer 7 compares the control amount FS1 thus calculated with the control amount FS2 (step 174). Then, the motor control circuit 11 is operated using the larger control amount (step 175 or step 176). According to such a driving method, there is a merit that an optimum ventilation amount can be assigned to each of the gas components (concentrations) of the temperature of the contaminated air.

Next, the driving of the ventilation fan for the specified time in step 161 in FIG. 7 will be described with reference to the flowchart in FIG.

The driving of the ventilation fan for the designated time is a process for sufficiently discharging the remaining contaminated air when the degree of contamination of the contaminated air is reduced by the driving of the ventilation fan from the start of driving. Specifically, when the ventilation fan is driven, the driving is forcibly continued for a predetermined time TM2.

In FIG. 10, the processing from step 178 to step 182 is the same as the processing for driving the ventilation fan (from step 172 to step 176) in FIG. When the predetermined time TM2 has elapsed, the microcomputer 7 stops the ventilation fan using the motor control circuit 11 (step 183). And step 1 in FIG.
Similarly to 71, the gas sensor output reference value SENφ and the temperature reference value THφ are updated (step 184).

Next, detection of the life of the ultraviolet sensor in step 163 in FIG. 7 will be described with reference to the flowchart in FIG. In the ultraviolet sensor life detection (step 163), in step 158 of the flowchart in FIG. 7, the microcomputer 7 integrates the time during which the ultraviolet sensor 3 detects the ignition of the gas stove by the built-in timer, and stores the integrated time: TML in a nonvolatile manner. The data is read from the memory 10 and compared with a predetermined time: TM4 (step 18).
5) If the TML has not reached TM4, the process proceeds to step 164 in FIG. However, if TML ≧ TM4, the microcomputer 7 determines that the ultraviolet sensor has deteriorated with time and has reached the end of its life, and notifies the life of the ultraviolet sensor (step 186). That is, the microcomputer 7 sends a signal to the sensor life informing device 13 shown in FIG. 1, notifies the user of the life of the ultraviolet sensor and issues an alarm or a synthesized voice by a voice synthesis IC, and stops the automatic driving function. .

Next, the deterioration detection of the gas sensor in step 166 in FIG. 7 will be described with reference to the flowchart in FIG. The microcomputer 7 first reads the initial value: P ₀ of the deterioration determination index P from the non-volatile memory 10 and reads the sensor operation temperature control circuit 14.
After setting the operating temperature to the rated operating temperature T ₀ (step 188), set the air pollution detection level to SC = SCD (step 189), measure the gas sensor output: SEN1, SC =
SEN1 / SENφ is calculated (step 190), the presence or absence of contaminated air is determined (step 191). When it is determined that contaminated air is generated, the process immediately returns to the main routine of FIG.
After the determination in 167, the air pollution detecting operation in step 144 in FIG. 6 is performed. If it is determined in step 191 that no contaminated air is generated, a specific resistance value _{T0 of the} gas sensor is calculated from the sensor output: SEN1 (step 192). Next, a signal is sent to the sensor operating temperature control circuit 14 to set the operating temperature of the gas sensor to the operating temperature for deterioration detection: T ₁ (° C.) (1 / 2T ₀ ≦ T ₁ ≦ 7 / 8T ₀ ) (step 193). after again, operating temperature: T ₁ to the corresponding dirty air detection level: set SCD '(step 19
4), Gas sensor output: Measure SEN2, SC = SEN2 / SENφ
(Step 195), and the presence or absence of contaminated air is determined again (Step 196). If it is determined that there is a possibility of generating contaminated air with SC ≧ SCD ′, the process immediately returns to Step 167 of the main routine in FIG. If it is determined that no contaminated air is generated due to SC <SCD ′, the intrinsic resistance value R _T1 of the sensor is calculated from SEN2 (step 197), and then the deterioration determination index: Pn = R _T1 / R _T0 is calculated (step 198). Then, it is determined whether the initial value Po of the deterioration determination index read from the nonvolatile memory 10 is 0 (step 199). If Po is 0, step 198
Is set as the initial value Po of the deterioration judgment index, and is stored in the nonvolatile memory 10 (step 20).
1) After returning to the main routine, perform a steady operation. If P is not 0 and the value is read into the non-volatile memory 10, a change in the deterioration determination index: Qn = Pn / Po is calculated (step 200), and this Qn and the predetermined deterioration compared to degrees determination level K ₃ (step 202), if K ₃ or less,
The microcomputer 7 determines that the gas sensor is extremely deteriorated and has reached the end of its life, and sends a signal to the sensor life informing device 13 to display the life of the gas sensor and to notify the life of the gas sensor by an alarm or synthesized voice (step 203). However, unless Qn is K ₃ or less, then deterioration degree determination level K ₁ (K _1> K ₃₎ as compared to (step 204), when Qn is not K ₁ or less, no cause performance degradation And returns to the main routine to perform a steady operation thereafter. If Qn is K ₁ below has caused performance degradation of the gas sensor, it is determined that the necessary self-correction, after the sensor has been degraded self-correction (step 205), microcomputer 7 sensor operation temperature control circuit To the operating temperature: T
It was allowed to return to T ₀ when contaminated air detected (step 206)
Thereafter, the process returns to step 167 of the main routine.

Next, the sensor deterioration self-correction (step 205) will be described with reference to the flowchart of FIG. In FIG. 13, in step 207, first, the change of the deterioration determination index: Qn is read from the nonvolatile memory 10, and then the deterioration determination levels K ₁ , K ₂ ,
Compared to K _3, depending on the degree of each degradation, contamination of the air detection level, after been reconfigured (step 208, 209, 210, and 211) to the SCD2 and SCD3 (SCD2 <SCD3), 1 of the main routine
The operation returns to the normal operation of steps 67 and 144, and the polluted air detection operation is performed.

Characteristic diagrams when the automatic ventilator of the present embodiment is actually driven are shown in FIGS. 14 to 17 and will be described in detail.

FIG. 14 is a characteristic diagram showing an operation when grilled fish is cooked using a gas stove. The horizontal axis represents time t, and the vertical axis represents the gas sensor output value SEN1 and the measured temperature value TH1.
Is shown. In FIG. 14, the solid line is the gas sensor output value SEN1
, And the dashed line indicates the measured temperature value TH1. In the drawing, the setting positions of the output ratio reference value SCD and the temperature difference reference values THD1 and THD2 are indicated by a two-dot chain line.

Time t ₁₀ represents a time update (FIG. 7 step 162) is performed for the reference value. In this point t _10, since the gas stove is not yet ignited, the count value PC of the pulse counter 4 for counting the output of the ultraviolet detector tube 3 is 0. The ignition of the gas stove is made at time t _11, UV detection pipe 3 supplies detect the ultraviolet rays emitted from the gas stove flames, a pulse corresponding to the pulse counter 4 to the radiation intensity of the ultraviolet.

The pulse counter 4 counts the output of the ultraviolet detection tube 3. Since the count value PC satisfies the condition (PC ≧ N) shown in step 155 in FIG.
The determination processing of 159 is performed. At time t ₁₁ in FIG. 14, yet,
Output change of gas sensor 1 and temperature sensor 2 is small, SC ≧
In order not to satisfy the condition of SCD or TC ≧ THD2, the ventilation fan is driven for a designated time described in step 161 of FIG. Here, the time from ignition of the gas stove to driving of the ventilation fan is extremely short.

Thereafter, the gas sensor output value SEN1 increases due to leakage of raw gas at the time of ignition of the gas stove. Eventually, time t
_When it becomes ₁₂ , the condition of step 159 in FIG. 7, that is, SC ≧ SCD is satisfied. As a result, the microcomputer 7 executes step 160 in FIG.
Driving of the ventilation fan described in (1) is performed. During the use of the gas stove, the count value PC keeps a relationship of PC ≧ N.

On the other hand, the gas sensor 1 detects gas components such as smoke, odor, and gas generated by burning fish. For this reason,
The gas sensor output value SEN1 as shown in time t ₁₄ from the time point t ₁₂ of Figure 14 is increased. In this case, the ventilation volume (air volume) of the ventilation fan is automatically controlled according to the value of the output ratio SC. At the same time, the temperature of the hot air generated by the gas stove increases with the elapse of the cooking time. The temperature sensor 2 detects the temperature of the hot air.

Temperature measurements TH1 as shown Thus from the time t ₁₂ in FIG. 14 to time t ₁₃ is increased. Becomes a time t _13, the conditions of FIG. 7 step 159, i.e. to satisfy the TC ≧ THD2. As a result, as shown in FIG. 9, the microcomputer 7 controls the ventilation amount (air volume) of the ventilation fan using the larger one of the control amount FS1 and the control amount FS2.

Cooking is completed and the stove fire extinguishing is carried out at time t _14, the count value PC of the pulse counter 4 becomes zero.
Further, the gas sensor output value SEN1 and the temperature measurement value TH1 start to decrease. Output ratio SC based on gas sensor output value SEN1
The condition at the time t ₁₅ FIG. 7 step 159 (SC ≧ SCD) ₅
Will not be satisfied. However, as before the temperature difference TC
Is to satisfy the condition of step 159 (TC ≧ THD2),
To time t ₁₆ is driven ventilation fan according to the temperature difference TC (FIG. 7 step 160) is performed.

Past time t _16, but not satisfy the conditions of FIG. 7 step 159, the specified time driving the ventilating fan in FIG. 7 step 161 is performed. By driving the ventilation fan for a specified time, the remaining hot air and contaminated air are discharged. Thereafter, when the specified time TM2 (for example, several minutes to several tens of minutes) is made at time t ₁₇ and passed, the microcomputer 7 stops the ventilation fan, and updates the reference value (FIG. 10 step 183,
184).

At the time t ₁₇ or later, the count value PC of the pulse counter 4
Is 0, and the ventilation fan is stopped. Microcomputer 7
Performs the determination processing of step 157 in FIG. 7, and the condition SC <SCD
And TC ≦ THD1 are satisfied, and step 16
Update the reference value of 2. The updating of the reference value is performed with the time TM1 as one cycle as shown in step 170 of FIG.

Next, the operation in the case where water is heated by the gas stove will be described with reference to the characteristic diagram of FIG. The description method in FIG. 15 is the same as that in FIG.

In Figure 15, time t ₂₀ represents a time update (FIG. 7 step 162) is performed for the reference value. Thereafter, when the ignition of the gas stove is made at time t _21, UV detection pipe 3
Detects the ultraviolet rays emitted from the flame of the gas stove and supplies a pulse to the pulse counter 4. Pulse counter 7
The counter value PC of the condition (PC
.Gtoreq.N), and the determination process of step 159 in the microcomputer 7 is performed.

At time t ₂₁ of FIG. 15, in order not to satisfy the condition of the SC ≧ SCD or TC ≧ THD2, performs specified time driving the ventilating fan in FIG. 7 step 161. The driving of the fan motor 25 of the ventilation fan is started almost simultaneously with the ignition of the gas stove. Thereafter, the gas sensor output value SENI increases due to the leakage of raw gas at the time of ignition of the gas stove.

Eventually, the time t ₁₂ when the condition of FIG. 7 step 159,
That is, SC ≧ SCD is satisfied. As a result, the microcomputer 7 drives the ventilation fan described in step 160 of FIG. In the case of a water heater, smoke, smell, gas, etc. are not usually generated,
The gas sensor output value SEN1 decreases. Then, at time t ₂₃ not satisfy the condition of step 159 (SC ≧ SCD).

Therefore, the microcomputer 7 switches the operation from driving the ventilation fan in step 160 to driving the ventilation fan for the specified time in step 161. On the other hand, the temperature of the hot air generated by the gas stove increases. This temperature rise includes the temperature rise of the surrounding air. The condition in step 159 before the specified time TM2 has elapsed, that is satisfied TC ≧ THD2, driving the ventilating fan again step 160 at time t ₂₄ is performed.

Hot water boiling, the gas stove of the extinguishing is performed at time t _25, the count value PC is zero of the pulse counter 4, and the temperature measurement value TH1 starts falling. As a result, no longer satisfied at t ₂₆ in FIG. 7 step 159 conditions (TC ≧ THD2). Then, the microcomputer 7 switches the operation from the driving of the ventilation fan in step 160 to the driving in step 161 again. Thereafter, at a time point t ₂₇ specified time TM2 has elapsed, the microcomputer 7 stops the ventilation fan, and updates the reference value (Fig. 10 step 183 and 184).

At the time t ₂₇ or later, the count value PC has become a 0,
Ventilation fan is off. The microcomputer 7 performs step 15 in FIG.
The process advances from step 7 to step 162 to update the reference value. As a result, automatic ventilating device of this embodiment is the same state as the state at time t _20.

Next, an operation in the case where the flame of the gas stove extinguishes during cooking due to boiling, boiling over, or blowing of wind will be described with reference to the characteristic diagram of FIG. In addition,
16 is the same as that of FIG. 15, and is a diagram showing the operation when water is heated by a gas stove, and is a characteristic diagram when a gas flame goes out on the way.

In FIG. 16, time point t ₃₀ indicates the time the update is performed for the reference value. Thereafter, when the ignition of the gas stove is made at time t _31, UV detection pipe 3 detects the occurrence of UV by the ignition, the microcomputer 7 drives the ventilation fan through the motor control circuit 11. In addition, the output value SEN1 of the gas sensor increases due to leakage of raw gas at the time of ignition of the gas stove.

Becomes a time t _32, the microcomputer 7 is a gas sensor output value SEN
The ventilation fan is driven (step 160 in FIG. 7) according to 1. At the time t ₃₃ ~ time t _34, the microcomputer 7 performs the specified time driving the ventilating fan according to the seventh FIG step 161. The above operation is the same as the operation in FIG.

Eventually, the hot water is gradually boiled temperature of hot air rises, the driving of the ventilation fan again FIG. 7 step 160 at time t ₃₄ is performed. Then, hot water at the time t ₃₅ is violently boiling and cow,
Hot water flows out occurs extinction of the gas stove flame at the time t _36. At the same time as the flame goes out, the count value PC of the pulse counter 4 becomes 0, and the measured temperature value TH1 starts to decrease.

On the other hand, the gas sensor output value SEN1 greatly increases in a short time due to generation of a large amount of raw gas. As a result, in step 149 of FIG. 6, PC <N and SC ≧ SCD
Is satisfied, and the microcomputer 7 determines that an abnormal situation (going out) has occurred. Then, the microcomputer 7 operates the motor control circuit 11 using the maximum control amount (step 150 in FIG. 6).

Therefore, the generated raw gas is rapidly discharged. Further, the microcomputer 7 sends a signal to the abnormality notifying device 12 to perform blinking of a lamp, warning by a buzzer, or notification by a synthesized voice. (Step 151 in FIG. 6).

Next, the operation when the cooking product (tempura oil) is ignited due to overheating or the like will be described with reference to the characteristic diagram of FIG.

Also in FIG. 17, as in the case of FIG. 16, the time t ₄₀
Indicates the time when the reference value was updated. Thereafter, when the ignition of the gas stove is made at time t _41, UV detection pipe 3 detects the occurrence of UV by the ignition, the microcomputer 7 drives the ventilation fan through the motor control circuit 11. In addition, the output value SEN1 of the gas sensor increases due to leakage of raw gas at the time of ignition of the gas stove.

Becomes a time t _42, the microcomputer 7 is a gas sensor output value SEN
The ventilation fan is driven (step 160 in FIG. 7) according to 1. At the time t ₄₃ ~ time t _44, the microcomputer 7 performs the specified time driving the ventilating fan according to the seventh FIG step 16. The above operation is the same as the operation in FIG.

Eventually, the uplink temperature of cooking oil is the temperature of the hot air also increases, driving the ventilation fan again FIG. 7 step 160 at time t ₄₄ is performed. Further excessive heating was performed,
At t ₄₅ , the temperature of the tempura oil becomes abnormally high and the smell of the tempura oil increases. The cooking oil is ignited at last time t _46, fire. Simultaneously with the occurrence of the fire, the count value PC of the pulse counter 4 rapidly increases and becomes equal to or more than a second set value N 'which is much larger than the set value N.

Slightly later, the temperature measurement value TH1 also sharply increases, and the temperature difference TC becomes equal to or more than the third lower temperature reference value THD2 'which is much larger than the temperature difference reference value THD2. The set value N 'and the temperature difference reference value THD2' are values stored in the ROM 9 in advance. As a result, in step 152 in FIG. 6, PC ≧ N ′, TC ≧ TH
The condition D2 'is satisfied, and the microcomputer 7 determines that an abnormal situation (fire occurrence) has occurred. Then, the microcomputer 7 stops driving the ventilation fan (FIG. 6, step 153).
For this reason, ventilation is stopped and the progress of the fire is slowed (weakened). Further, the microcomputer 7 includes an abnormality notification device 12
Signal, and a warning is given by blinking a lamp, a buzzer or a synthesized voice (step 15 in FIG. 6).
Four).

The automatic ventilation device according to the present invention is provided with a microcomputer 7.
Alternatively, an abnormality notification unit connected to the abnormality notification device 12 may be incorporated, and an external device (for example, a telephone) may be controlled via the unit, and a notification or the like using the external device may be performed when a flame goes out or a fire occurs. it can.

It should be noted that the signal of the ultraviolet sensor for measuring the degree of the flame can be stably operated even if the signal is controlled using not the absolute value of the output but the change value of the output.

〔The invention's effect〕

According to the present invention, the driving of the ventilation fan can be started almost simultaneously with the start of cooking, the ventilation fan can be automatically controlled by detecting hot air or contaminated air, and the reference value can be set according to the environmental conditions of the place where it is used. The automatic setting automatically improves the usability.In addition, the self-diagnosis of the degree of performance deterioration of the gas sensor can be automatically performed, and the self-correction can be performed according to the deterioration.
Since the correction contents are stored in the non-volatile memory, they are not adversely affected by a power failure or the like.
Malfunction is less likely to occur. Furthermore, since the life of the gas sensor and ultraviolet sensor can be reported, high reliability can be maintained for a long time, and abnormal situations such as extinguishing of flame during cooking and ignition (fire) can be automatically and promptly dealt with. Moreover, it is possible to provide an automatic ventilator capable of notifying a user by display and alarm.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a control system of an automatic ventilation device according to one embodiment of the present invention, FIG. 2 is a diagram showing a structure of the automatic ventilation device according to one embodiment of the present invention, and FIG. From, various elapsed time, a characteristic diagram showing the relationship with the specific resistance value of the gas sensor when the operating temperature of the gas sensor is changed, FIGS. 4 and 5 are characteristic diagrams showing the performance of the gas sensor over time, 6 to 13 are diagrams showing a flowchart of the microcomputer 7 shown in FIG. 1, and FIGS. 14 to 17 are characteristic diagrams when the automatic ventilation device of the present invention is driven. 1 ... reducing gas (gas) sensor 2 ... temperature sensor 3 ... ultraviolet sensor (ultraviolet detection tube) 4 ... pulse counter 5 ... multiplexer 6 ... A / D converter 7 ... … Microcomputer, 8… RAM, 9… ROM, 10… Non-volatile memory, 11… Motor control circuit, 12… Abnormality notification device, 13… Sensor life notification device, 14 …… Sensor operating temperature control circuit.

Continued on the front page (72) Inventor Toshio Shinozaki 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Home Appliances Research Laboratory, Hitachi, Ltd. (72) Inventor Yasutaka Noguchi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Inside the Home Appliance Research Laboratory (72) Katsuo Takashima 1-1-1 Higashitaga-cho, Hitachi City, Ibaraki Prefecture Inside Taga Sangyo Co., Ltd. (56) References JP-A-59-15735 (JP, A) JP-A-62-166238 ( JP, A) JP-A-62-69040 (JP, A) JP-A-57-64517 (JP, U) JP-A-62-95216 (JP, U) JP-A-62-198435 (JP, U)

Claims (10)

(57) [Claims] An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and each of the sensors A control circuit for processing the output signal of the fan motor to control the fan motor; and a means for detecting self-aging of the sensor and a means for notifying sensor life. each time reaching the time degradation detection condition is satisfied when the determined operating temperature of the rated operating temperature of the gas sensor: T ₀ and this lower predetermined set operating temperature is changed to T _1, the operating temperature T ₀ and T deterioration determination index from the resistance value of the gas sensor in the ₁ R _T0 and R _T1: P _n = as well as the operation and storage of the R _T1 / R _T0, the initial value of the deterioration determination index: a gas sensor using the initial using P ₀ Change of the deterioration determination index La: Q _n = P _n /
Calculating P ₀ , further, as a means for self-correction of deterioration with time of the gas sensor, setting a plurality of detection levels of contaminated air corresponding to the change of the deterioration determination index: Qn, furthermore, a life display, and an alarm or synthesized voice. An automatic ventilator, characterized by having a service life informing means for informing by means of: 2. An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, and a fan capable of discharging contaminated air. A control circuit for processing the output signal of the fan motor to control the fan motor; and a means for detecting self-aging of the sensor and a means for informing the life of the sensor. Lifetime notifying means for accumulating and storing the time during which the ultraviolet sensor detects a flame from the start of use and for notifying by a life display and an alarm or synthesized voice when the accumulated time reaches a predetermined time. An automatic ventilation device characterized by having: 3. A deterioration determination index when the gas sensor is used: _Pn.
And deterioration determination index changes: as Q _n and contaminated air detection level means for storing a detection level after self-correction of the non-volatile memory: and characterized by using any of the CMOS RAM having a backup means by EEPROM or battery The automatic ventilator according to claim 1, wherein 4. The method according to claim 1, wherein the predetermined time-dependent deterioration detection condition of the gas sensor is such that the output signal of each of the sensors fluctuates below a predetermined value for a predetermined time. Automatic ventilator as described. 5. An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and each of the sensors. A control circuit for processing the output signal of the fan motor to control the fan motor; a raw gas leak notification unit; an abnormal temperature rise notification unit; As time-dependent deterioration self-detecting means and sensor life notifying means, each time a predetermined time-dependent deterioration detection condition is satisfied, the operating temperature of the gas sensor is set to a rated operating temperature: T ₀ and a predetermined setting operation lower than this. temperature: T ₁ is changed, the operating temperature T ₀ and the resistance value of the gas sensor in the T ₁ R _T0 and deterioration determination index from R _T1: while calculating and storing the _{P n = R T1 / R T0} , poor The initial value of the determination index: changes in the degradation determination index from the gas sensor using an initial using _{P 0: Q n = P n} /
Calculating P ₀ , further, as a means for self-correction of deterioration with time of the gas sensor, setting a plurality of detection levels of contaminated air corresponding to the change of the deterioration determination index: Qn, furthermore, a life display, and an alarm or synthesized voice. An automatic ventilator, characterized by having a service life informing means for informing by means of: 6. An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and each of the sensors. A control circuit for processing the output signal of the fan motor to control the fan motor; a raw gas leak notification unit; an abnormal temperature rise notification unit; As the time-dependent deterioration self-detecting means and the sensor life notifying means, the time during which the ultraviolet ray sensor detects a flame is accumulated and stored from the start of use, and when the accumulated time reaches a predetermined time, An automatic ventilator having a service life informing means for providing a service life display and an alarm or performing notification by a synthesized voice. 7. A nonvolatile memory: an EEPROM as means for accumulating and storing a time during which the ultraviolet sensor detects a flame.
Or CMOS with backup means by battery
7. The automatic ventilator according to claim 2, wherein one of the RAMs is used. 8. An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and each of the sensors. A control circuit for processing the output signal of the fan motor to control the fan motor; a raw gas leak notification unit; an abnormal temperature rise notification unit; As gas leak notification means, when the level of the output signal of the ultraviolet sensor drops below a first predetermined value, and when the amount of change in the output signal of the gas sensor increases above a second predetermined value, a raw gas leak display and An automatic ventilator having means for giving an alarm or a synthesized voice. 9. An ultraviolet sensor for detecting ultraviolet rays emitted from a flame, a gas sensor for detecting contaminated air, a temperature sensor for detecting hot air, a fan capable of discharging contaminated air, and each of the sensors. A control circuit for processing the output signal of the fan motor to control the fan motor; a raw gas leak notification unit; an abnormal temperature rise notification unit; As a temperature rise notifying means, when the level of the output signal of the ultraviolet sensor is higher than a third predetermined value and the amount of change of the output signal of the temperature sensor is higher than a fourth predetermined value, an abnormal temperature rise An automatic ventilator having means for displaying and displaying a warning or a synthetic voice. 10. The control circuit, when the level of the output signal of the ultraviolet sensor falls below a first predetermined value and the amount of change of the output signal of the gas sensor increases above a second predetermined value. The fan motor is controlled to maximize the ventilation volume of the fan, the level of the output signal of the ultraviolet sensor increases from a third predetermined value, and the amount of change in the output signal of the temperature sensor increases to a fourth level. 9. The automatic ventilator according to claim 8, wherein the control circuit controls the fan motor so as to reduce the amount of ventilation by the fan to zero when the value exceeds a predetermined value.