JPH08196845A - Air cleaner - Google Patents

Abstract

PURPOSE: To provide an air cleaner processing the output of a dust sensor, detecting even a small amt. of dust with precision and without any malfunction. CONSTITUTION: The output of a dust sensor 1 is inputted to a microprocessor 2 directly or through an amplifier 3, and the inputs are selected in the microprocessor 2. When the amt. of dust is small, the output is inputted through the amplifier 3, and, when the input is large, the output is directly inputted. Further, the revolving speed of a motor 5 is determined based on the value, and the lighting of an indicating lamp in an indicating circuit 6 is also determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air purifier for collecting dirt in the air, and more particularly to an output processing means of a sensor for detecting dust.

[0002]

2. Description of the Related Art As shown in FIG. 13, the output of a dust sensor mounted in a conventional air purifier is such that the output voltage with respect to the amount of dust changes substantially linearly. For example, in FIG. When trying to capture the change range of 0 to 1.0 mg / cubic meter, the output voltage of the sensor is 2 to 8
Generally, the range of V and voltage change is wide.

[0003]

However, in such an output means, when the microprocessor is to process a wide range of dust amount of 0.1 mg / cubic meter to 1 mg / cubic meter, it is usually the input voltage range of the microprocessor. Is about 0 V to 5 V, so that particularly when trying to detect a minute amount of dust with high accuracy, the resolution is low and the detection accuracy is poor, and there is a big problem that malfunction occurs such that, for example, even if a minute amount of dust is present, it cannot be detected. Was.

An object of the present invention is to solve these problems and to provide an air purifier with high detection accuracy.

[0005]

The first means of the present invention for achieving the above object is to output the output of a dust sensor through an amplifier when the dust level is low and directly when the dust level is high. A plurality of output means for outputting are provided.

The second means passes the output of the dust sensor through the amplifier when the dust level is low, and when the amount of dust reaches the saturation level of the output of the amplifier, the gain of the amplifier is varied. The problem solving means is to provide a plurality of output means for directly outputting the output of the dust sensor when the dust level exceeds a certain level.

Further, the third means is to solve the problem by providing an output means for connecting the output of the dust sensor to the amplifier and varying the gain of the amplifier according to the amount of dust.

The fourth means is to solve the problem by providing an output means for connecting the output of the dust sensor to the logarithmic amplifier.

[0009]

According to the first means of the present invention, since the amplification is performed only when the amount of dust is small, it is possible to improve the accuracy of detecting a very small amount of dust, and when the amount of dust exceeds a certain level, the output of the dust sensor itself. Since the output is performed, it is accurate when the amount is very small, and when the amount is large, the accuracy is not required, and a rough output can be achieved.

Further, according to the second means, the gain of the amplifier is varied according to the amount of dust, so that the accuracy of detecting a minute amount of dust is improved and the gain of the amplifier is varied even if the amount of dust increases. Therefore, the detection can be performed with high accuracy, and the user can be provided with an appropriate air flow rate.

According to the third means, since the dust detection accuracy is improved over the entire area, it is possible to provide an air purifier with good usability.

Further, according to the fourth means, since the accuracy of detecting a minute amount of dust can be improved with a simple structure, a small and light air cleaner can be provided.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG. Reference numeral 1 denotes a dust sensor, the output of which is directly connected to the first input terminal A of the microprocessor 2 and also to the second input terminal B via the amplifier 3. A motor 5 is connected to the output of the microprocessor 2 via a motor drive circuit 4, and a display circuit 6 is also connected to the output. Rotational speed of motor 5 and display circuit 6
The display of is switched according to the output of the dust sensor 1.

The operation of the above configuration will be described. When the relationship between the amount of dust of the dust sensor 1 and the output voltage is as shown in FIG. 2, the voltage of FIG. 2 is input to the first input terminal A of the microprocessor 2 according to the amount of dust. Becomes Further, since the output amplified by the amplifier 3 is input to the second input terminal B, assuming that the gain of the amplifier 3 is double, for example, when the dust amount is 0.5 mg / cubic meter, it is 2.5 V in FIG. Since it reaches 5V, the operating voltage of the microprocessor is 5 for dust above it.
Since it is V, it does not exceed 5 V, and eventually the voltage input as shown in FIG.

At this time, the processing of the microprocessor 2 is shown in FIG.
If the amount of dust is 0 to 0.5 mg / cubic meter, the input B is 5 V or less, so the value of the second input terminal B is 0.5 to 1 mg / cubic meter. Is 5 V, the value of the first input terminal A is taken in as the output of the dust sensor 1. 2 and 3 when the amount of dust is 0 to 0.5 mg / cubic meter.
Comparing with, the increase of the output voltage with respect to the change of the dust amount changes 0.5V when the dust amount changes by 0.1 mg / cubic meter in FIG. 2, and changes 1V in FIG. Since FIG. 3 is larger, the detection accuracy for a minute amount of dust is improved.

Next, a second embodiment of the present invention is shown in FIG.
In FIG. 5, the gain variable circuit 7 for varying the gain of the amplifier 3 is connected as shown in the figure, and the relationship between the dust amount and the output voltage of the amplifier 3 when the gain variable circuit 7 is not outputting from the microprocessor 2 is shown. 0.1 mg / as in 6 (a)
A change in the output voltage of 2.5 V with respect to a change in the amount of dust in the cubic meter, and the microprocessor 2 is set in the gain variable circuit 7.
As shown in FIG. 6B, the relationship between the dust amount and the output voltage of the amplifier 3 when it is being output is 1 V for a change in the dust amount of 0.1 mg / cubic meter.

In the processing of the microprocessor 2 at this time, as shown in FIG. 7, the input B is read as it is only when the input B is 5 V or less, and when it exceeds 5 V, the output of the gain variable circuit 7 is read, and the gain variable circuit is further read. Since the output of 7 is also subdivided and judged, subdividing a small amount of dust into
The detection accuracy can be improved.

Next, a third embodiment of the present invention is shown in FIG.
In FIG. 8, the first gain variable circuit 8 and the second gain variable circuit 9 for varying the gain of the amplifier 3 are connected as shown in the figure,
When the gain variable circuits 8 and 9 do not output from the microprocessor 2, the relationship between the dust amount of the amplifier 3 and the output voltage is shown in FIG. 9A, and the first gain variable circuit 8 outputs the dust amount from the microprocessor 2. FIG. 9B shows the relationship between the dust amount and the output voltage of the amplifier 3 when the amplifier 3 is in operation, and the relationship between the dust amount and the output voltage of the amplifier 3 when being output from the microprocessor 2 to the second gain variable circuit 9. Figure 9 (c)
And

As described above, when the gains of the variable gain circuits 8 and 9 are changed and the processing of the microprocessor 2 at this time is sequentially judged as shown in FIG. Therefore, from the time when the dust amount is small to the time when it is large, all the dust amounts can be accurately detected with a simple circuit configuration.

Next, a fourth embodiment of the present invention is shown in FIG. In FIG. 11, when the output of the dust sensor 1 is connected to the logarithmic amplifier 10, the output of the logarithmic amplifier 10 becomes as shown in FIG. 12. Therefore, for example, when the change curve of the example of FIG. 12 is used, the amount of dust is 0.5 mg / cubic meter or less. In this case, the change in the output voltage with respect to the change in the dust amount becomes large, and the change in the output voltage with respect to the change in the dust amount becomes smaller when the amount is larger than that.Therefore, the dust amount can be accurately detected with only a small input with a simple configuration. Becomes

[0021]

As is apparent from the above embodiments, the first
According to the method, a minute amount of dust can be accurately detected,
An air purifier that does not malfunction can be provided.

Further, according to the second means, a minute amount of dust can be further subdivided and detected, so that the dust can be detected with high accuracy.

Further, according to the third means, the amount of dust can be detected accurately with one input over the entire band.

Further, according to the fourth means, it is possible to detect a minute amount of dust with high accuracy with a simple structure.

[Brief description of drawings]

FIG. 1 is a block diagram of an air purifier showing a first embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the dust amount and the output voltage in the same embodiment.

FIG. 3 is a diagram showing the relationship between the amount of dust and the output voltage after amplification in the example.

FIG. 4 is a flowchart showing input selection contents in the same embodiment.

FIG. 5 is a block diagram of an air purifier showing a second embodiment of the present invention.

FIG. 6 is a diagram showing the relationship between the amount of dust and the output voltage in the example.

FIG. 7 is a flowchart showing input selection contents in the same embodiment.

FIG. 8 is a block diagram of an air purifier showing a third embodiment of the present invention.

FIG. 9 is a diagram showing the relationship between the amount of dust and the output voltage in the same example.

FIG. 10 is a flowchart showing the contents of input selection in the embodiment.

FIG. 11 is a block diagram of an air purifier showing a fourth embodiment of the present invention.

FIG. 12 is a diagram showing the relationship between the amount of dust and the output voltage in the same example.

FIG. 13 is a diagram showing a relationship between a conventional dust amount and an output voltage.

[Description of Reference Signs] 1 dust sensor 2 microprocessor 3 amplifier 7 gain variable circuit 8 first gain variable circuit 9 second gain variable circuit 10 logarithmic amplifier

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor ▲ Taka ▼ Masaki Hashi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A dust sensor for detecting suspended dust in the air is mounted, means for displaying the air volume and the degree of contamination in the air is provided by the value of the output of the dust sensor, and the output of the dust sensor is An air purifier equipped with a plurality of output means that outputs a signal through an amplifier when the level is low and directly outputs when the level is high. 2. A dust sensor for detecting floating dust in the air is mounted, and means for displaying the air volume and the degree of dirt in the air is provided by the value of the output of the dust sensor, and the output of the dust sensor is When the level is low, the output of the dust sensor is passed through the amplifier, and when the amount of dust reaches a level where the output of the amplifier becomes saturated, the gain of the amplifier is changed, and when the dust level exceeds a certain level, the output of the dust sensor is directly output. An air purifier provided with a plurality of output means. 3. A dust sensor for detecting suspended dust in the air is mounted, means for displaying the air volume and the degree of dirt in the air is provided by the value of the output of the dust sensor, and the output of the dust sensor is connected to an amplifier. An air purifier provided with output means for varying the gain of the amplifier according to the amount of dust. 4. A dust sensor for detecting suspended dust in the air is mounted, means for displaying the air volume and the degree of dirt in the air is provided by the value of the output of the dust sensor, and the output of the dust sensor is output to a logarithmic amplifier. An air purifier equipped with output means for connection.