JP2001263821A - Hot air type heater with air cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot air type heater with air cleaners for accurately detecting the contamination of air even if moisture changes due t the discharge of a combustion gas into a room in the hot air type heater where an air cleaner mounting a semiconductor type gas sensor is integrated. SOLUTION: The hot air type heater with air cleaners is provided with a semiconductor type gas sensor 4 for detecting the contamination of indoor air, a moisture detection means 5 for detecting absolute moisture in a room, a correction means 6 for correcting a signal that is detected by the gas sensor 4 with a correction coefficient that is determined by an absolute moisture being detected by the moisture detection means 5, and a means 7 for judging the degree of air contamination for judging the contamination of indoor air based on the detection signal of the gas sensor that is corrected by the correction means 6. Also, a gas sensor for detecting moisture that is the same system as the semiconductor type gas sensor and detects moisture change in response to only vapor can be used instead of the moisture detection means 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a warm air heater equipped with an air purifier, which detects air pollution by a semiconductor gas sensor and controls the air purifier optimally.

[0002]

2. Description of the Related Art Conventionally, a household air purifier is equipped with a semiconductor gas sensor for detecting air contamination during smoking or cooking, and detects air contamination based on a detection signal of the gas sensor. In addition, there is known an apparatus in which switching of the cleaning ability and indication of the degree of contamination are switched in accordance with the contamination of air.

FIG. 8 shows a configuration example of a semiconductor gas sensor (hereinafter simply referred to as a gas sensor) 21. Gas sensor 2
Reference numeral 1 denotes a gas sensing part 22 mainly composed of tin oxide and a heater part 23 for raising the temperature of the gas sensing part 22 to about 300 ° C. to about 400 ° C. High temperature gas sensing part 22
In pure air, oxygen is adsorbed on the surface of tin oxide in clean air, and at that time, oxygen captures free electrons in the tin oxide, and a potential barrier is generated at a grain boundary of the tin oxide, so that a constant electric resistance is exhibited. When the gas sensing part 22 is exposed to a pollutant gas in the air (such as hydrogen generated when a cigarette burns), the pollutant gas reacts with the adsorbed oxygen on the tin oxide surface, and the oxygen adsorbed on the tin oxide surface decreases, The potential barrier decreases, and the electric resistance decreases. The gas sensor 21 detects air pollution based on the change in the resistance value.

[0004] On the other hand, the demand for purifying indoor air while the heater is in use has led to the development of air purifiers and heaters that combine functions similar thereto. Combination with a heater is also being carried out.

[0005]

However, when the atmosphere of the gas sensing part 22 contains water vapor, the semiconductor gas sensor 21 undergoes an oxidation reaction between the water vapor and the adsorbed oxygen, resulting in a decrease in resistance value similar to the reaction with the pollutant gas. Is generated. This allows
When the absolute humidity in the room in which the air cleaning device equipped with the gas sensor 21 is installed changes, the output of the gas sensor 21 changes regardless of air pollution, and when the amount of water vapor increases, the gas sensor 21 reacts as if the pollution was detected. .

[0006] Further, when the gas warm air heater is operated, steam is generated by gas combustion. In particular, in the case of a warm air heater of the indoor air circulation type, since the combustion gas is exhausted indoors,
When the heating operation is performed, the amount of steam in the room gradually increases. Therefore, when an air purifying device having a function of detecting air pollution by mounting the gas sensor 21 is combined with a gas hot air heater, the operation of the gas hot air heater increases the amount of water vapor in the room, and the gas sensor 21 Reacts to changes in the amount of water vapor and outputs a signal indicating that there is contamination even in the absence of pollutant gas.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention is directed to a hot air heater in which an air purifier equipped with a semiconductor-type gas sensor is combined, even if the amount of water vapor changes due to discharge of combustion gas into the room. It is an object of the present invention to provide a warm air heater equipped with an air purifying device that can accurately detect contamination of air.

[0008]

According to the present invention, there is provided a warm air heater equipped with an air purifying device, comprising a semiconductor gas sensor for detecting contamination of indoor air, humidity detecting means for detecting absolute indoor humidity, and a detection signal of the gas sensor. And a degree of air pollution determining means for determining the degree of contamination of indoor air based on the detection signal of the gas sensor corrected by the correcting means. Even if the gas sensor reacts to the water vapor discharged by the combustion by the operation of the hot air heater, the humidity detecting means detects the indoor humidity condition and makes a correction according to the humidity, and outputs the water vapor. Since the change can be canceled out, the contaminated gas in the air is accurately detected without being affected by the change in the amount of water vapor in the room even during heating, and the air purifying device is operated properly. Door can be.

In addition, instead of the humidity detecting means and the correcting means based on the detection signal, a gas sensor for detecting a change in humidity is characterized by responding mainly to water vapor in the same manner as a semiconductor gas sensor. The same operation and effect can be obtained by correcting the detection signal of the gas sensor with the detection signal of the humidity detection gas sensor and providing a correction means for canceling the output change due to the humidity in the gas sensor.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A gas warm air heater with an air purifier according to one embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a gas warm air heater with an air purifier, and a gas warm air heater 2 and an air purifier 3
And are integrally combined. In the air purification device section 3,
Semiconductor type gas sensor 4 for detecting pollutant gas in air
And humidity detecting means 5 for detecting the absolute humidity in the room where the appliance is installed.

FIG. 2 shows a configuration of a control device for detecting the degree of air pollution in the air cleaning device section 3 and controlling its operation. In FIG. 2, a correcting means 6 for correcting the humidity of the output signal of the gas sensor 4 based on the absolute humidity signal detected by the humidity detecting means 5 and an air pollution degree determining means 7 for determining an air contamination state based on the corrected gas sensor output signal. A capacity control means 8 for determining the operation capacity of the air purifying device 3 based on the degree of air pollution, and a dirt display control means 9 for giving an indication of the level of dirt.

Next, the operation will be described. Figure 3 shows the room
In the state where the air cleanliness inside is almost constant, the gas hot air heater unit 2
Of gas sensor 4 with respect to the passage of time when heating operation
FIG. 6 is a diagram showing changes in a force signal (resistance value RO) and an absolute humidity s.
is there. The state of the heating operation is T ₀To T₁Up to
Combustion at capacity, T₁To T_TwoUp to T, T _Two
Thereafter, the combustion is again performed at the maximum capacity. According to FIG.
Absolute humidity due to gas combustion under air cleanliness conditions
As the (water vapor amount) s increases, the gas sensor resistance value RO decreases.
It turns out that it is less.

FIG. 4 is a diagram showing the dependence of the gas sensor resistance value RO obtained from the results of FIG. 3 on the absolute humidity s. In FIG. 4, the change in the gas sensor resistance value RO with respect to the absolute humidity s is represented by the absolute humidity 11.2 g / m ³ (20
(° C., 65% RH). This value can be determined by the above experiment.

Thus, the absolute humidity s is detected by the humidity detecting means 5 so that the correcting means 6 detects the absolute humidity s.
Can be corrected by the resistance ratio α (s) obtained experimentally in advance as described above. The correction equation is shown in equation (1).

RO / α (s) (1) The absolute humidity where α is 1 is 11.2 g / m ³ (2
0 ° C., 65% RH) is determined according to the use conditions of the device.

The air pollution degree determination means 7 determines air contamination based on the output signal of the gas sensor whose humidity has been corrected and the influence of humidity has been removed, and enables accurate operation capability control and display of the contamination level.

Next, another embodiment of the gas warm air heater with an air purifier of the present invention will be described with reference to FIGS. The same components as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted. Only different points will be described.

In FIG. 5, in the present embodiment, a humidity sensor 15 for detecting a change in humidity is provided in place of the humidity detector 5, characterized by responding mainly to water vapor in the same manner as the gas sensor 4. ing.

FIG. 6 shows a configuration of a control device for detecting the degree of air pollution in the air cleaning device section 3 and controlling its operation. In FIG. 6, a correcting means 16 for correcting the humidity of the output signal of the gas sensor 4 based on the humidity information detected by the humidity detecting gas sensor 15, and an air pollution degree determining means 7 for determining an air contamination state based on the corrected gas sensor output signal.
And an ability control means 8 for determining the operation ability of the air purifying device 3 based on the degree of air pollution, and a stain display control means 9 for notifying a guide of the stain.

Next, the operation will be described. FIG. 7 is a diagram showing the absolute humidity dependence of the gas sensor resistance value RO and the humidity detection gas sensor resistance value RS during gas combustion. In FIG. 7, the absolute humidity is 11.2 g / m for each absolute humidity s.
³ shows the resistance ratio α to the resistance value of the gas sensor 4 and the resistance ratio α1 to the resistance value of the humidity detection gas sensor 15 at (20 ° C., 65% RH). The gas sensor resistance value has a correlation of α (s) and α1 (s) with the absolute humidity s, and the value can be obtained experimentally. Also, α
(S) and α1 (s) have a linear correlation with the absolute humidity s, and can be considered by a linear approximation.
Each approximate expression is shown in Expressions (2) and (3).

Α (s) = A × s + B (2) α1 (s) = a × s + b (3) where the slope A of the equation (2) is the absolute humidity of the gas sensor 4. , And the slope a in the equation (3) is the change rate of the resistance value of the humidity detecting gas sensor 15 with respect to the change of the absolute humidity. Therefore, the correlation coefficient γ between the gas sensor 4 and the humidity detection gas sensor 15 with respect to the change in absolute humidity can be expressed by the following equation (4).

Γ = A / a (4) This value can be obtained experimentally.

In the control of a gas sensor mounted on a home air purifier, the range of the target gas is wide and its concentration is low, so that the rate of change from the reference value at a predetermined time (resistance value / It is general to judge the contamination based on the reference resistance value).

In this case, the correction means 16 sets the resistance change rate β of the gas sensor 4 (= RO / RO reference value),
The resistance change rate β1 of the humidity detection gas sensor 15 (= RS /
RS reference value), and a change in indoor humidity due to gas combustion is estimated from the change rate β1 of the humidity detection gas sensor 15. In order to cancel the influence of the humidity of the gas sensor 4, the resistance change rate β of the gas sensor 4 is corrected by the equation (5).

(Β / β1) × γ (5) The air pollution degree judging means 7 can judge the dirt based on the gas sensor signal in which the influence of the humidity has been canceled, and the actual dirt condition can be further improved. It becomes possible to control the combined driving ability and display the dirt level.

By forming the gas sensor 4 and the humidity detecting gas sensor 15 in the same sensor, the manufacturing conditions can be made uniform, the humidity dependency of each sensor can be easily managed, and the correlation between each sensor can be obtained. It will be easier.

[0028]

According to the warm air heater with an air purifier of the present invention, as is apparent from the above description, a gas sensor for detecting contaminated gas, a humidity detecting means for detecting indoor humidity or a gas sensor for detecting humidity. And a means for correcting the gas sensor output signal based on the humidity information, so that even when the output of the gas sensor fluctuates due to water vapor discharged by combustion when the warm air heater is heated, the gas sensor is based on the humidity information. Correction can be made to eliminate the influence of humidity on the output.
Therefore, even at the time of simultaneous use with the hot air heater, the gas sensor can detect the correct air pollution status, and the advantageous effects of controlling the performance of the air purifying device suitable for the indoor situation and reporting the contamination level can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a gas warm air heater with an air purifying device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a control device of the embodiment.

FIG. 3 is a diagram showing an output of a gas sensor and an output of an absolute humidity detector during a heating operation according to the embodiment.

FIG. 4 is a diagram showing the absolute humidity dependency of the gas sensor output of the embodiment.

FIG. 5 is a configuration diagram of a gas warm air heater with an air purifying device according to another embodiment of the present invention.

FIG. 6 is a block diagram of a control device of the embodiment.

FIG. 7 is a diagram showing the absolute humidity dependence of the gas sensor output and the humidity detection gas sensor output during the heating operation of the embodiment.

FIG. 8 is a conceptual diagram of a semiconductor gas sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas warm air heater with air purifier 2 Gas warm air heater unit 3 Air purifier unit 4 Gas sensor 5 Humidity detecting means 6 Correcting means 7 Air pollution degree determining means 15 Humidity detecting gas sensor 16 Correcting means

Continued on the front page (72) Inventor Itsuo Igarashi 1006 Kazuma Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd. Person Tetsuya Hiraoka 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi F-term in Osaka Gas Co., Ltd. 3L028 AC06 EB04 EC04

Claims (2)

[Claims] A semiconductor gas sensor for detecting contamination of indoor air; a humidity detecting means for detecting absolute humidity in the room;
Correction means for correcting the detection signal of the gas sensor with a correction coefficient determined by the absolute humidity detected by the humidity detection means, and air pollution degree determination for determining the contamination of the indoor air based on the detection signal of the gas sensor corrected by the correction means A hot air heater with an air purifier. 2. A semiconductor gas sensor for detecting contamination of indoor air, a humidity sensor for detecting a change in humidity, characterized by responding mainly to water vapor in the same manner as the semiconductor gas sensor, and detecting the gas sensor. Correction means for correcting the signal with the detection signal of the humidity detection gas sensor to cancel the output change due to humidity in the gas sensor, and air pollution degree determination for determining the contamination of the indoor air based on the detection signal of the gas sensor corrected by the correction means A hot air heater with an air purifier.