JP3093540B2 - air purifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air purifier having a sensor for detecting air contamination and capable of automatic operation.

[0002]

2. Description of the Related Art Conventionally, in this type of air purifier, air contamination is detected by an air purifier main body 1 in order to perform an automatic operation of purifying air by changing an air volume in response to a change in air contamination. A detection unit 6 that adjusts the amount of air in the room to be sucked through an air inlet provided on the outer surface of the air purifier main body 1 in response to a change in the detection value of the detection unit 6, so that dust and the like in the sucked air are adjusted. Was removed by the dust collecting unit in the air purifier main body 1, and was blown into the room again from the air outlet provided on the outer surface of the air purifier main body 1. Detector 6 for detecting this air stain
A gas sensor is used as the detecting means 7 for detecting the contamination of the air by utilizing the fact that the internal resistance changes according to the concentration of the reducing gas in the air, converting it to a voltage and outputting it. 2, the reference value previously updated by the detection value of the detection unit 6 is compared with the detection value
When the increase or decrease of the output voltage exceeds the set sensitivity voltage,
Automatic operation was performed by changing the degree of dirt and air flow.

[0003]

However, in such a conventional air purifier, the mounting position of the gas sensor is that of the air blower 5.
If the position is cooled by the influence of the air blow, the temperature of the gas sensor drops when the air is blown and the internal resistance decreases, the output voltage decreases, and conversely, when the air blow stops, the temperature of the gas sensor decreases. As the output voltage increases due to the increase in internal resistance, the output of the gas sensor changes even though it is not a change in air dirt, thereby determining the degree of air dirt during automatic operation and the amount of air blown. Has the disadvantage of changing. Especially when the sensitivity voltage of the gas sensor is set to be much higher than the sensitivity of the change when the output voltage goes down, the sensitivity voltage of the gas sensor is set to be much higher than the sensitivity when the output voltage goes down in order to react quickly when the contamination of the air advances.
The malfunction appeared remarkably.

[0004]

In order to solve the above-mentioned drawbacks, the present invention focuses on this point and, in particular, comprises a blower, a detector for detecting dirt in the air, In an air purifier including a control unit that controls a blowing unit by comparing a detection value of a detection unit with a reference value that is updated based on a change in the contamination with the detection value of the contamination as an initial value, the blowing unit is stopped. For a fixed time from, the update interval of the reference value by the detection unit is shorter than the update interval when the blowing unit is operating.

[0005]

In response to an increase in the detection value due to a rise in the temperature of the detecting means when the blower section stops and the blower does not hit the detecting means of the detecting section, a predetermined time has elapsed since the blower section stopped. By setting the interval for updating the reference value to be shorter than when the blowing unit 5 is operating, it is possible to prevent an increase in the degree of contamination and malfunction of the blowing unit 5 and to ensure control in automatic operation.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An air purifier according to the present invention will be described below with reference to a preferred embodiment shown in the drawings. Reference numeral 1 denotes an air purifier main body, which is controlled by the control unit 2. Reference numeral 3 denotes an operation unit. When the user operates the operation unit 3, an operation signal is output to the control unit 2, and the control unit 2 controls the air purifier main body 1 according to the signal. Reference numeral 4 denotes a display unit which displays various information such as the operation state and operation contents of the air purifier main body 1 and the degree of air contamination and various errors based on a display signal from the control unit 2. Reference numeral 5 denotes a blower, which drives an electric blower (not shown) in accordance with a control signal of the controller 2 to inhale and clean air in the room, and then exhausts the room again. Reference numeral 6 denotes a detection unit having a detection unit 7 such as a gas sensor for electrically converting dirt in the air, and outputs an electric signal from the detection unit 7 to the control unit 2. Reference numeral 8 denotes a power supply for operating the entire air purifier.

Reference numeral 9 denotes a comparison unit which has a temperature sensor 10 for detecting room temperature. Further, when the air contamination is constant in a general temperature range of room temperature (for example, 15 ° C. to 30 ° C.), the air is blown. The change in the output voltage due to the rise in the temperature of the detection means 7 after the stoppage is stored as data, and the change in the output voltage from the detection means 7 and the temperature at which the blowing is stopped at the temperature stored as the data. The change in output voltage due to the rise is compared.

The operation of the automatic operation of the air purifier configured as described above will be described. First, the operation unit 3 is operated and the power supply 8 is operated.
Is input, the output voltage of the gas sensor 3 minutes after power-on, at which the gas sensor is stabilized, is registered in the control unit 2 as the initial value of the reference value, and "small (stop)" is set as the initial value of the contamination degree. You. In this embodiment, the degree of dirt is set to four levels of “large”, “medium”, “small (fine)”, and “small (stop)” and displayed on the display unit 4 and the blower unit 5
Airflow is "powerful", "weak", "fine", "stop"
And displayed on the display unit 4. In automatic operation, each air volume corresponds to each degree of contamination, so that when the degree of contamination becomes "large", the air volume becomes "powerful", and when the degree of contamination becomes "medium", the air volume becomes "weak" Is done.

The sensitivity of the gas sensor is set by the user switching the sensitivity changeover switch on the operation unit 3, and the degree of contamination and the update sensitivity of the reference value are determined based on the sensitivity. In this embodiment, the sensitivity is “high”, “medium”,
In three stages of “low”, the sensitivity voltage is 0.08 [V], 0.14 [V],
At 0.20 [V], they are set to 0.18 [V], 0.24 [V], and 0.30 [V], respectively, in the output voltage decreasing direction (dirty degree reduction). The reason that the sensitivity voltage is higher in the output voltage increasing direction than in the output voltage decreasing direction at each stage is to respond quickly to the increase in the degree of dirt, and to increase the air volume in a timely manner to suppress the increase in air dirt. This is because a sufficient operation time is required for the decrease in the degree of dirt, and the degree of dirt and air volume are reduced after the dirt is surely reduced.

As described above, after the power is turned on, the reference value and the initial value of the degree of contamination are set, and the sensitivity voltage is set. When the operation mode switch of the operation unit 3 is set to "automatic operation" and the start button is pressed, the automatic operation is started. Be started. First, air contamination is detected by a gas sensor (step 11), and the detected value is equal to or more than (reference value + sensitivity voltage in increasing direction) or less than (reference value-sensitivity voltage in decreasing direction), or both. Judge which of the following applies. (Step 12) If the detected value of the gas sensor is equal to or more than (reference value + sensitivity voltage in the increasing direction), it is determined whether the state has continued for 8 seconds or more. (Step 13) If the state continues for 8 seconds or more, the detection value is updated as a new reference value, the degree of dirt is raised by one step, the air volume is increased by one step, and the detection of dirt is further continued. I do. (Step 14)

When the detection value of the gas sensor is equal to or less than (reference value-sensitivity voltage in the decreasing direction), it is determined whether the state has continued for 30 seconds or more. (Step 15) If the state continues for 30 seconds or more, the detected value is updated as a new reference value, the degree of dirt is reduced by one step, the air volume is reduced by one step, and the detection of dirt is continued. I do. (Step 16) The difference between the duration of the sensitivity voltage in the increasing direction of 8 seconds or more and the sensitivity voltage in the decreasing direction of 30 seconds or more is that it responds quickly to the increase in dirt, and to the decrease in dirt. The above-mentioned continuation time is set in order to ensure that the dirt has been reduced before responding.

When the detection value of the gas sensor is larger than (reference value-sensitivity voltage in decreasing direction) and smaller than (reference value + sensitivity voltage in increasing direction), or when the detection value of the gas sensor is (reference value + sensitivity in increasing direction). Voltage) or more but the duration of the state is less than 8 seconds, and when the detection value of the gas sensor is less than (reference value-sensitivity voltage in the decreasing direction) but the duration of the state is less than 30 seconds, First, it is determined whether the blowing unit 5 is operating. (Step 17)

If the blower unit 5 is operating, it is determined whether or not 10 minutes or more have passed since the detection of the detected value (step 18), and 10 minutes or more have passed since the detection of the detected value. In this case, it is further determined whether or not the detected value is equal to or less than the reference value (step 19). If the detected value is equal to or less than the reference value, the detected value is updated as a new reference value to reduce the degree of contamination by one step (step 16). If the detected value exceeds the reference value, the reference value is not updated and only the contamination degree is reduced by one level. (Step 20) If the elapsed time from the detection of the detected value is less than 10 minutes, the dirt detection is continued. (Step 11)

If the blower 5 is stopped, it is first determined whether or not 10 minutes have passed since the blower 5 was stopped.
(Step 21) If the elapsed time since the blower unit 5 was stopped is less than 10 minutes, it is further determined whether one minute or more has elapsed since the detection of the detection value (Step 22). If one minute or more has passed since the detection, the change in the output voltage for one minute after the air supply was stopped when the dirt was constant at that temperature stored in the comparison unit 9 and the The comparison unit 9 compares the change in the detected value within one minute. (Step 23)

If the change in the detected value within one minute is sharper, it is determined that the air has become contaminated in addition to the increase in the output voltage due to the temperature rise, and the reference value is not changed. Only the degree of contamination is reduced by one step. (Step 20) Conversely, if the change in the detected value during the one minute is more gradual or the same, it is determined that the increase in the output voltage is due to only the temperature rise, and the detected value is updated as a new reference value. To lower the degree of contamination by one step. (Step 16) If the elapsed time from the detection of the detected value is less than one minute, the detection of the dirt is continued. (Step 1
1)

The elapsed time from when the blower 5 stops is 10
If the detected value is longer than 10 minutes, it is determined whether 10 minutes or more have elapsed since the detection of the detected value (step 18). Is determined to be less than or equal to the reference value (step 19). If the detected value is equal to or less than the reference value, the detected value is updated as a new reference value to reduce the degree of contamination by one step (step 16). Is exceeded, the reference value is not updated and only the degree of contamination is lowered by one step. (Step 20) If the elapsed time from the detection of the detected value is less than 10 minutes, the dirt detection is continued. (Step 11)

Here, a description will be given of a case where the blower 5 stops and the blower does not hit the gas sensor, and the temperature of the gas sensor rises. When the degree of contamination of the air is reduced by the operation of the blower unit 5 and the degree of contamination becomes “small (stop)”, the blower unit 5 is stopped, so that the ventilation does not hit the gas sensor and the temperature of the gas sensor decreases. By starting to rise, the detection value of the gas sensor also starts to rise. (Fig. 3)

Up to 10 minutes after the blower unit 5 is stopped, the reference value is updated at intervals of one minute, and the detected value of the gas sensor is equal to or more than (reference value + sensitivity voltage in the increasing direction) within one minute. When the state continues for 8 seconds or more (step 13)
The control unit 2 judges that this is not only an increase in the detected value due to the temperature rise of the gas sensor, but also that the air is obviously contaminated, and when the detected value continues for 8 seconds, the detected value is used as a reference value. And the degree of dirt is updated from "small (stop)" to "small (fine)", and the air flow is "stopped" accordingly.
, The air blower 5 starts operating. (Step 14)

If the detected value of the gas sensor for one minute does not exceed (reference value + sensitivity voltage in the increasing direction) for 8 seconds or more, the change of the detected value for one minute is compared with that for one minute. When the dirt at that temperature stored in the unit 9 is constant, the change in the output voltage after the blowing is stopped is compared by the comparing unit 9. (Step 23) If the change in the detected value in one minute is steeper than the change in the data stored in the comparing unit 9, this is due to not only the increase in the detected value due to the temperature rise of the gas sensor, but also The control unit 2 determines that the air has begun to be contaminated, and lowers the contaminant level by one step without updating the reference value. However, in reality, the contaminant level remains at the minimum “small (stop)” and the air volume is “stopped”. Remains. (Step 20)

Conversely, if the change in the detected value during one minute is more gradual or the same as the data stored in the comparing section 9, this is because the detected value is increased only by the temperature rise of the gas sensor. Is determined, the reference value is updated, and the degree of dirt is reduced by one step. However, the degree of dirt is actually the lowest “small (stop)” and the airflow is “stopped”. (Step 16) Therefore, as shown in FIG. 3, when the detected value is increased only by the temperature rise of the gas sensor, the reference values are updated to a, b, c, and d at one-minute intervals after the blower unit 5 is stopped. After 10 minutes have passed since the blower unit 5 was stopped, f to g
The interval becomes 10 minutes as in the case of updating to, and the blower unit 5 remains stopped.

Thereafter, when the detection value of the gas sensor is equal to or more than (reference value + sensitivity voltage in the increasing direction) and the state continues for 8 seconds or more, or when it is equal to or less than (reference value-sensitivity voltage in the decreasing direction), the state is changed to When 10 minutes have passed since the blower unit 5 was stopped without any state in the case where it continued for 30 seconds or more (step 21), 10 minutes after the detection value was further detected.
Determine if more than one minute has elapsed. (Step 18) If 10 minutes or more have not passed since the detection value was detected, the detection of air contamination is continued (Step 11), and if 10 minutes or more passed since the detection value was detected. When the detected value is equal to or less than the reference value (step 19), the detected value is updated to the reference value, and when the degree of contamination is other than "small (stop)", the degree of contamination is reduced by one step, and The blower unit 5 also lowers the air volume by one step (step 16), and when the detected value exceeds the reference value (step 19), the reference value is not updated and the contamination level is not "small (stop)" except for the lowest degree of contamination. In the case of (1), the degree of contamination is lowered by one step, and in response to this, the blowing unit 5 also lowers the air flow by one step (step 20), and thereafter detects a change in the detected value at intervals of 10 minutes.

Incidentally, the gas sensor of the present embodiment uses a sensor in which the increase in the detected value due to the temperature rise after the air supply is stopped is smaller than the "high" sensitivity voltage in the increasing direction. As long as is constant, the reference value and the degree of contamination are not updated due to the temperature rise due to the stop of the air supply.

[0023]

As described above, according to the present invention, the blower, the detector for detecting dirt in the air, and the reference value updated by the change in dirt with the detected value of dirt when the power is turned on as an initial value. And a control unit that controls the blowing unit by comparing the detection value of the detecting unit and the blowing unit. Prevents malfunction due to temperature rise of the detection unit when the blower unit is stopped, even if the detection unit of the detection unit is installed in the place where the air blower unit blows in the air purifier body by shortening the update interval when Since it is possible, the installation place of the detecting means is free, and an air purifier that emphasizes the design can be made.

[Brief description of the drawings]

FIG. 1 is a basic block diagram of an air purifier according to an embodiment of the present invention and a conventional example.

FIG. 2 is a flowchart of an air purifier to which one embodiment of the present invention is applied.

FIG. 3 is an operation explanatory view showing an output change of the gas sensor and an operation of the air purifier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air purifier main body 2 Control part 5 Blower part 6 Detection part 7 Detection means 9 Comparison part

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F24F 7/00 F24F 7/007

Claims (1)

(57) [Claims] 1. A blower unit 5, a detection unit 6 for detecting dirt in the air, a reference value updated by a change in dirt with a detected value of dirt when power is turned on as an initial value, and a detection value of the detection unit 6. In the air purifier provided with the control unit 2 that controls the blower unit 5 by comparing the air blower unit 5, the blower unit 5 operates the interval of the update of the reference value by the detection unit 6 for a fixed time after the blower unit 5 stops. An air purifier characterized in that the interval between updates is shorter than when the air purifier is operating.