JP3255897B2 - Air quality detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor for detecting indoor air contamination of a building air conditioner, a house, and the like, and a detecting device provided with the sensor.

[0002]

2. Description of the Related Art In recent years, energy saving has been promoted in houses and buildings.
In addition, airtightness has been improved to improve air conditioning efficiency.
On the other hand, such tightness is caused, for example, by smoking
Dust, H _Two, CO and other gases, building materials, etc.
Aldehyde, volatile organic gas (VOC gas), stove
And NO generated from burning appliances such as_X, SO_X, CO_Twoetc
Gas, CO produced by human breathing_TwoAnd also tobacco
Odors such as odor, body odor, putrefaction odor, and bad odor remain in the room.
And contaminates indoor air, adversely affecting occupants. Building
In accordance with the building environmental hygiene management standards, CO_TwoBased on concentration
Despite standard ventilation, the V
Problem with sick building syndrome caused by OC gas
It has become. Therefore, such indoor polluted air
Energy-saving and comfort while maintaining ventilation and air purifiers.
Discharge and removal are required.

[0003] Further, there is a demand for measurement using a human sense of smell as an index of indoor air pollution.

[0004] Therefore, it has been known to detect indoor air pollution using a CO ₂ concentration or gas sensor and perform ventilation or air cleaning.

Conventionally, this type of air quality detecting device has generally been configured as shown in Japanese Patent Application Laid-Open No. 1-181026. Hereinafter, the configuration will be described with reference to FIG.

As shown in the figure, a carbon monoxide sensor 101
A, the hydrogen sensor 101B, the propane sensor 101C, the oxygen sensor 101D, and the smoke sensor 101E output analog signals to the comparators 102A to 102E, respectively. Comparator 1
The reference levels of 02A to 02E are set in advance, and when the indoor air pollution increases and the sensor output exceeds the reference level, the output becomes, for example, "H".

Further, each output of the comparators 102A to 102E is
It is input to the calculating means 103. The calculating means 103 performs an OR operation and calculates one of the outputs of the sensors 101A to 101E.
If at least the reference level is exceeded, a signal is output to the output means 104 to operate the ventilation fan.

[0008]

In such a conventional air quality detecting device, when setting a reference level and obtaining a sensor output, a reference value is obtained from a sensor signal, and a difference between the reference value and the sensor output is used. The reference value generally uses a sensor signal in clean outside air.

However, in the room to be measured,
Gas generated from building materials, furniture, and the like is present as a background in comparison with clean outside air. For example, hydrocarbons such as methane, alcohols, VOC gas, aldehyde and the like. Although these gases are detrimental to health at high concentrations, they are present at low levels without any health problems and their concentrations and components vary from room to room. Therefore, there is a problem that the sensor signal in the clean outside air is obtained only when a window is opened or a ventilation fan is operated in a house, and in an office building, a large amount of outside air is introduced in the middle period of spring or autumn.

Further, many sensors used in the air quality detection device are semiconductor gas sensors, and the output and sensitivity of these sensors change with time and with the temperature and humidity of the atmosphere. Therefore, there is a problem that the reference value must be updated and the temperature and humidity must be corrected.

[0011] The present invention solves the above-mentioned problem, and monitors the minimum value of the sensor signal for more than half a year, so that spring,
The clean outside air level obtained in the middle of autumn is reliably detected as a reference value.

A second object is to correct the obtained reference value by temperature and humidity so that even if the reference value is obtained in a season where the climate is completely different, the change of the indoor air pollution state is not affected by the temperature and humidity. Is to detect with high accuracy.

[0013]

A first means for achieving the first object of the present invention comprises one or more sensors for detecting contamination of indoor air and a signal from the sensors for a predetermined time. Sampling means for sampling each time, and 1
Minimum value calculating means for calculating the minimum value of the signal of the sensor for a certain period of not less than days and not more than six months, minimum value storing means for storing the minimum value output from the minimum value calculating means for at least six months, and the minimum value storing means A clean level calculating means for obtaining an output of the sensor in the clean air from the minimum value stored in the sensor; and a dirt amount for calculating a dirt amount of the indoor air by comparing the output value of the clean level calculating means with a signal of the sensor as a reference value. The apparatus is provided with a calculating means and an output means for outputting the amount of dirt to the outside.

A second aspect of the present invention for achieving the second object is as follows.
Means for detecting temperature and humidity of indoor air, and reference value correcting means for correcting the output value of the clean level calculating means from the temperature and humidity output from the temperature and humidity sensor. This is an additional configuration.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, the minimum value of a sensor signal for the past six months or more is stored and used as a reference value so that the minimum value is always obtained in the middle period of spring or autumn. The reference value of the obtained clean outside air level can be obtained.

According to the configuration of the second means, the reference value is corrected based on the temperature and humidity obtained by the temperature and humidity sensor, so that the temperature and humidity environment when the reference value is obtained and the temperature and humidity at the time of measurement are obtained. Even in different cases, an accurate clean outside air level can be obtained.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. The same parts as those in the conventional example are denoted by the same reference numerals, and description thereof is omitted.

As shown in FIG. 1, a plurality of sensors 1 for detecting contamination of indoor air output sensor signals to sampling means 2. The sampling means 2 samples the sensor signal at regular intervals and outputs the sensor signal to the dirt amount calculation means 9.

The minimum value calculating means 14 is a sampling means 2
The minimum value of the sensor output for a certain period is calculated from the output of (1) and is output to the minimum value storage means 15. The minimum value storage means 15 stores the minimum value output from the minimum value calculation means 14 for at least six months (for example, when the minimum value calculation means 14 calculates the minimum value of the sensor signal for one week, the minimum value storage means 15). Stores 53 or more minimum values). The clean level calculating means 16 calculates a clean outside air level sensor signal from the minimum values stored in the minimum value storing means 15 and outputs the signal to the dirt amount calculating means 9 as a clean level.

The output means 10 outputs the dirt amount, which is the output of the dirt amount calculation means 9, to an LED, a panel meter, a ventilator, an air purifier, or the like.

As the sensor 1, various types of sensors can be used as long as they are sensitive to pollutants representing the polluted state of indoor air to be detected. For example, when detecting smoking, a hydrogen sensor or a CO sensor as a cigarette sensor, or when detecting a VOC gas, an alcohol sensor,
When detecting a person or combustion, a carbon dioxide gas sensor, and when detecting a bad odor, a bad odor sensor includes a hydrogen sulfide sensor, an ammonia sensor and the like. Further, the number of the sensors 1 may be any number of one or more types according to the detection target.

Here, the sensor signal is used for ventilation (ventilation fan operation,
The operation shown in FIG. 2 is performed in response to a load such as opening of a window and introduction of outside air) or tobacco. The sensor signal indicates a clean level signal when a ventilating operation is performed and outside air is introduced. When the ventilating operation is stopped, the sensor 1 detects a gas existing as a background in the room and indicates a background level signal. Changes depending on the contamination of

The gas existing as the background is mainly of hydrocarbon type, alcohol type and organic solvent type, and the concentration is several tens to several hundreds PPb in total, which is a level which is not a problem for human health. Existing.

According to the above configuration, the minimum value of the sensor signal for at least the past six months is stored, and the clean level is obtained from the minimum value group. Can be used as a value.

As described above, according to the air quality detecting device of the first embodiment of the present invention, the clean outside air level, which is the reference value of the sensor signal, is obtained from the minimum value over the past six months or more, and is obtained by introducing outside air in the middle period. Since the clean outside air level is used as the reference value, the degree of contamination of the indoor air can be accurately obtained.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. The same portions as those in the conventional example and the embodiment of the present invention are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 3, the temperature and humidity sensor 17 measures the temperature and humidity in the room, and outputs the room temperature and the humidity to the reference value correcting means 18. The clean level calculating means 16 outputs the clean level to the reference value correcting means 18. The reference value correction means 18 corrects the clean level output from the clean level calculation means 16 with the room temperature and humidity output from the temperature and humidity sensor 17 and outputs the corrected value to the dirt amount calculation means 9 as a reference value.

According to the above configuration, the cleanness level sensor signal can be corrected in temperature and humidity to be used as a reference value.

As described above, according to the air quality detecting device of the second embodiment of the present invention, the temperature and humidity at the time of updating the reference value and the temperature and humidity at the time of measurement are different from each other in order to correct the temperature and humidity of the reference value. Even in this case, the degree of contamination can be accurately obtained.

[0030]

As is apparent from the above embodiments, according to the present invention, a large amount of outside air is introduced in the middle period of spring or autumn by using the minimum value of the sensor signal in the past six months as a reference value. Thus, an air quality detection device can be provided which has an effect of always having the clean outside air level obtained as a reference value.

Furthermore, even when the temperature and humidity at the time of updating the reference value and the temperature and humidity at the time of measurement are different from each other by correcting the reference value with the room temperature and the humidity obtained by the temperature and humidity sensor, contamination of the indoor air can be accurately detected. It is possible to provide an air quality detecting device having an effect capable of detecting.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an air quality detection device according to a first embodiment of the present invention.

FIG. 2 is a graph showing a trend of a sensor signal of the air quality detection device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of an air quality detection device according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional air quality detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor 2 Sampling means 3 Signal storage means 4 Change amount calculating means 5a Output drop determining means A 5b Output drop determining means B 6 Change amount integrating means 7 Clean determining means 8 Clean level storing means 9 Dirt amount calculating means 10 Output means 11 Stable Degree monitoring means 12 Background level storage means 13 Reference value storage means 14 Minimum value calculation means 15 Minimum value storage means 16 Clean level calculation means 17 Temperature / humidity sensor 18 Reference value correction means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-199142 (JP, A) JP-A-63-101741 (JP, A) JP-A-7-151720 (JP, A) JP-A-6-171720 317549 (JP, A) JP-A-6-130014 (JP, A) JP-A-4-369338 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 27/00-27 / 24 F24F 11/02

Claims (2)

(57) [Claims] 1. A sensor for detecting contamination of indoor air, one or more sensors, sampling means for sampling a signal of the sensor at predetermined time intervals, and a sensor which is at least one day and no more than six months from a sensor signal sampled by the sampling means. Minimum value calculating means for calculating the minimum value of the sensor signal for a certain period, minimum value storing means for storing the minimum value output from the minimum value calculating means for at least half a year, and minimum value stored in the minimum value storing means A clean level calculating means for obtaining an output of the sensor in the clean air, a dirt amount calculating means for calculating a dirt amount of the indoor air by comparing an output value of the clean level calculating means with a signal of the sensor as a reference value, An air quality detection device including an output unit that outputs a dirt amount to the outside. 2. A temperature and humidity sensor for detecting temperature and humidity of indoor air, and a reference value correcting means for correcting an output value of the clean level calculating means based on temperature and humidity output from the temperature and humidity sensor. Air quality detector.