JPH0866642A - Method for detecting deterioration of dust collection efficiency in air cleaner - Google Patents

Abstract

PURPOSE: To detect the dust collection efficiency or its deterioration to judge the necessity of cleaning or exchanging by periodically or automatically measuring the dust collection efficiency of an air cleaner. CONSTITUTION: This air cleaner 1 consists of an ionizing part 4 and a dust collecting part 2, and the characteristic of the circuit formed with the ionizing part 4 or dust collecting part 2 as a capacitor is measured. Concretely, a high voltage generating circuit 5 is connected to the discharging part or charging part formed with the ionizing part 4 or dust collecting part 2 as a capacitor, and the discharging characteristic or charging characteristic of the ionizing part 4 or dust collecting part 2 is digitized and sampled by a CPU 8 to compare the sampled value with the reference value. Otherwise, the discharging voltage or charging voltage of the ionizing part 4 or dust collecting part 2 is compared with the reference value by a comparator circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting dust collection efficiency or deterioration thereof, which is reduced by dust or the like adhering to an ionization section or a dust collection section in an air cleaner for an automobile or the like.

[0002]

2. Description of the Related Art It is well known that, for example, in an air cleaner of an automobile, dust adheres to the ionization section or the dust collecting section, and the dust collecting efficiency of the entire cleaner decreases with time. In order to eliminate this decrease in dust collection efficiency, it is common to clean or replace the ionization section or the dust collection section in order to remove the dust that has adhered. Therefore, the means for determining the replacement time is important. Conventionally, based on the dust collection efficiency deterioration characteristics calculated from the performance of the dust collection unit, a method of periodically replacing the dust collection unit by setting a theoretical cleaning or replacement interval, an ionization unit or a collection unit measured by a dedicated measuring instrument. The main method was to calculate the dust collection efficiency from the number of dust particles in the dust part and clean or replace it when the calculated value is lower than the reference value.

[0003]

Although the above method is not necessary, the ionization section or the dust collection section can be cleaned or replaced,
Even if the dust collection efficiency is already inferior, it may not be cleaned or replaced until the time of cleaning or replacement, and the method is economically inefficient because it is processed regardless of the actual dust collection efficiency of the purifier. Is. In addition, since the measuring instrument for measuring the number of dusts is expensive and labor-intensive, this method is not a very economical means either, and there is no standard for when to measure the number of dusts. Therefore, it is not practical.

The ideal method is to measure the dust collection efficiency of the purifier on a regular basis and determine that cleaning or replacement is necessary if the measured value is below a predetermined reference value.
Therefore, the deterioration of the dust collection efficiency due to the adhesion of dust is grasped as a change in the electrical characteristics of the ionization section or the dust collection section, the electrical characteristics are measured, and the measured values are automatically processed. Alternatively, it was decided to examine the means to detect the deterioration.

[0005]

As a result, the developed one is an air purifier consisting of an ionization part and a dust collection part, and is cleaned by measuring the circuit characteristics in which the ionization part or the dust collection part is configured as a capacitor. It is a method for detecting deterioration of dust collection efficiency in an air purifier that detects dust collection efficiency of a container or deterioration thereof. The object to be detected is one of the ionization part and the dust collection part, or both in parallel or in combination. If it is determined that the dust collection efficiency has deteriorated as a result of the detection, it may be indicated to the outside by lighting a lamp, a buzzer alarm, or the like.

Specifically, in an air purifier comprising an ionization section and a dust collection section, a high voltage generation circuit is connected to a discharge circuit or a charging circuit in which the ionization section or the dust collection section is configured as a capacitor, and the ionization section or the dust collection section is connected. The discharge or charge characteristics of the dust collector are digitized and sampled by the CPU to compare the sample value with the reference value, or the discharge voltage or charge voltage of the ionizer or dust collector is compared with the reference value by a comparison circuit. There is a method of detecting the dust collection efficiency of the ionization section or the dust collection section or its deterioration by comparison. The former can be called a soft method and the latter can be called a hard method. In the hardware method, in order to specify the comparison reference for each measurement, the output of the comparison circuit is latched within a predetermined time from the start of measurement. In addition to this, the measurement method may be measurement of impedance characteristics and frequency characteristics of a circuit in which the ionization section or the dust collection section is configured as a capacitor. The high voltage generator used is
It can also be used as the power supply for the air purifier.

[0007]

In the air purifier, the ionization section and the dust collection section each have a property as a condenser. However, the electrostatic capacity of the ionization part or the dust collection part is not constant, and it gradually increases due to the adhesion of dust. In the method for detecting dust collection efficiency deterioration of the present invention, the ionization section or the dust collection section is measured by measuring the characteristics of the discharge circuit or the charging circuit in which the ionization section or the dust collection section whose capacity increases as described above is configured as a capacitor. The degree of dust collection efficiency is detected, and when it is determined that the dust collection efficiency has deteriorated, it is displayed to the outside and the appropriate time for cleaning or replacing the ionization part or the dust collection part is known. is there. The characteristics of the discharge circuit or the charging circuit are represented as a time constant including the capacity of the ionization section or the dust collection section, and can be detected as a change in voltage in time series.

In the soft method, this output is A / D
Digitize with a conversion circuit etc. and compare the sample value (voltage value) after a certain time with the reference value (voltage value) to calculate the degree of deterioration of dust collection efficiency, or the sample value (voltage value) is constant Compare the time to reach the value (voltage value) with the reference value (time),
Calculate the dust collection efficiency or its deterioration degree. The CPU, for example, outputs a signal to the outside when the calculated value becomes negative, and displays a warning by a lamp, a buzzer, or the like.

In the hardware method, the output from the discharge circuit or the charging circuit is compared with a reference value (voltage value) by a comparison circuit, and the output can be obtained from this comparison circuit only when the dust collection efficiency deteriorates. The latch circuit holds the output from the comparison circuit after a predetermined time from the start of measurement, outputs the held output to the outside, and displays a warning by a lamp, a buzzer or the like. For example, when the charging circuit is configured with the dust collecting part as a capacitor, and the lamp is lit when the output of the comparison circuit, which is (output from the charging circuit-reference value), is negative,
If the capacity becomes large due to the adhesion of dust, the output of the charging circuit will gradually decrease after a predetermined time, and the lamp will turn on when it falls below the reference value, and the dust collection efficiency or its deterioration, that is, the cleaning or replacement time must be known. Will be able to.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, referring to the drawings, an embodiment will be described in which a device for replacing the dust collecting portion 2 of a vehicle-mounted air purifier 1 is constructed by using the dust collecting efficiency monitoring method of the present invention. explain. FIG. 1 is a circuit configuration diagram in which the output voltage of a discharge circuit in which the dust collecting unit 2 of the purifier 1 is configured as a capacitor is processed by a soft method, and when the replacement time of the dust collecting unit 2 is warned to the outside by lighting the lamp 3. 2 is a circuit configuration diagram for performing similar processing by a hardware method. Even if the discharge circuit is configured by using the ionization section 4 instead of the dust collection section 2 as a capacitor, equivalent processing can be performed.

First, a soft method will be described. FIG.
As can be seen from FIG. 3, the air purifier 1 including the ionization section 4 and the dust collecting section 2 is connected to the high voltage generating circuit 5, and the resistor 6 is inserted in parallel with the dust collecting section 2 to form a discharge circuit. To do.
The output extracted from the dust collector 2 is converted into a voltage value suitable for processing by the CPU 8 by the voltage conversion circuit 7, and is digitized by the A / D conversion circuit 9. The CPU 8 performs processing such as ON / OFF of the high voltage generation circuit 5, sampling of the digitized discharge voltage value, and lighting of the notification lamp 3 according to the result of the calculation processing. As described above, the CPU 8 is convenient because it can perform various kinds of processing comprehensively and in cooperation with each other.

The procedure for detecting the deterioration of the dust collecting efficiency of the dust collecting portion 2 and displaying it to the outside by the notification lamp 3 is as follows. First, a high voltage is applied to the purifier 1 whose high voltage generating circuit 5 is turned on by the CPU 8, and the dust collecting unit 2 is charged as a capacitor. When the high voltage generation circuit 5 is turned off by the CPU 8 in this state, the charging voltage is discharged through the resistor 6, and the discharging voltage is the voltage conversion circuit 7 and the A / D conversion circuit 9
Is input to the CPU 8 through and sampled.

The CPU 8 samples the digitized discharge voltage value under constant conditions. The sampling conditions include a. Discharge time with respect to the reference voltage or b. Discharge voltage after a fixed time. In this embodiment using the CPU 8, both can be selected by software. In any case, the time until the measurement is started is determined with reference to the turning off of the high voltage generation circuit 5 by the CPU 8. In the present embodiment, the sample value of the discharge voltage after 5 seconds from turning off the high voltage generating circuit 5 and the reference value are compared, and if the difference becomes negative (that is, the sample value exceeds the reference value). , CPU 8 lights the notification lamp 3.

FIG. 3 shows the dust collection efficiency and the high voltage generation circuit 5.
The graph which shows the relationship with the discharge voltage 5 seconds after turning off is shown. As can be seen from this graph, the discharge voltage increases when the dust collection efficiency is low. If the dust collection efficiency is
If the dust collecting unit 2 is replaced when the discharge voltage drops to 20%, it can be understood that the notification lamp 3 may be turned on when the discharge voltage falls below about 500V. The sample value processed by the CPU 8 is not the discharge voltage itself. Therefore, a conversion table corresponding to this graph is stored in the CPU 8 and the comparison with the reference value as described above is guided by the arithmetic processing.

Next, a hardware method will be described. In FIG. 2, the discharge circuit in which the dust collecting unit 2 is configured as a capacitor is the same as that in the soft method. However, ON / OFF of the high voltage generation circuit 5 is not a soft switch using a CPU but a hard switch or a soft switch based on a signal from another circuit. This switch turns on the timer 11 for controlling the delay of the latch circuit 10 at the same time as turning off the high voltage generation circuit 5. The discharge voltage of the dust collector 2 is passed through the voltage conversion circuit 7 to the voltage comparison circuit 12
Is input to the + (plus) side, and the reference voltage is input from the reference voltage generating circuit 13 to the other- (minus) side. The latch circuit 10 latches the output of the voltage comparison circuit 12 by the timer 11 after a fixed time from the turning off of the high voltage generation circuit 5, and the display drive circuit 14 is activated by the latched output to turn on the notification lamp 3.

In this hardware method, the sampling condition of the discharge voltage is limited to the discharge voltage value after a fixed time from turning off the high voltage generating circuit 5, and the discharge voltage value after the constant time is compared with the reference value. As possible, the latch circuit 10 holds the output of the voltage comparison circuit 12 which is the difference between the two. In the present embodiment, the output of the voltage comparison circuit 12 becomes (discharge voltage value-reference value), so this output becomes positive, that is, the discharge voltage is increased because the dust adheres to the dust collecting unit 2 and the capacity increases. When it becomes higher, the notification lamp 3 is turned on.
The reference value here is a value determined from the graph shown in FIG. 3, and is a voltage value corresponding to a discharge voltage value of about 500 V when the dust collection efficiency is reduced to 20%, for example. Since the discharge voltage is lowered by the voltage conversion circuit 7, this reference value also uses a value smaller than the above value. This reference value may be derived from a conversion table created in advance.

When comparing the software method and the hardware method, it is clear that the former can perform integrated processing including the purifier by the CPU and can change the sampling condition for obtaining the sample value. Can be changed or a new function can be added. On the other hand, in the latter, the only condition that can be changed is the delay time until the latch and the reference voltage, but since the measurement of dust collection efficiency can be realized with a simple circuit, it can be built in a purifier, etc. Have significant advantages. However, it is not necessary to use both separately, and they may be used in combination. For example, a circuit by a hardware method may be provided in the front stage for each of the dust collecting section and the ionization section having a different degree of deterioration of the dust collection efficiency, and a circuit by a soft method for processing both may be provided in the subsequent stage.

Finally, an example in which the dust collecting unit 2 is used as a capacitor to configure a charging circuit will be described. FIG. 4 is a circuit configuration diagram in which the output voltage of the charging circuit configured by the dust collecting unit 2 as a capacitor is processed by a soft method, and when the dust collecting efficiency is deteriorated, an alarm lamp 3 is turned on to warn the outside. Yes, FIG. 5 is a circuit configuration diagram for performing similar processing by a hardware method. Even if the charging circuit is configured by using the ionization unit 4 instead of the dust collection unit 2 as a capacitor, equivalent processing can be performed.

As can be seen by comparing FIG. 4 and FIG. 1 or FIG. 5 and FIG. 2, the basic circuit configuration is the same even when a charging circuit in which the dust collecting unit 2 is configured as a capacitor is used. However, in order to utilize the charging characteristics, a. The resistor 15 is inserted in series with the dust collector 2, b. The measurement starts after the high voltage generation circuit 5 is turned on (in the discharge circuit described above, (The measurement starts after the voltage generation circuit 5 is turned off). Therefore, contrary to the case of the discharge circuit described above, when the charging voltage after a fixed time becomes equal to or less than the reference value or when the time until the charging voltage reaches the constant value becomes long, the dust collecting unit 2 collects. It is considered that the dust efficiency has deteriorated, and an alarm lamp 3 warns the outside.

In addition to the example illustrated this time, the ionization part or the dust collection part is regarded as a single capacitor, and the charging characteristic by the DC constant current is measured, or an AC circuit combined with a coil instead of a resistor is constructed, The impedance characteristic and the frequency characteristic may be measured. However, when using this AC circuit, the AC voltage to be applied to the ionization section or dust collection section must be prepared separately from the high voltage generation circuit, and it must be linked to the ON / OFF state of the air purifier. Since it is not possible to make measurements, it is necessary to turn the air purifier off and then start the measurement circuit again. From this point, it can be said that the method of measuring the output voltage of the discharge circuit or the charging circuit in conjunction with ON / OFF of the above-described high voltage generation circuit is a simpler and more practical method.

[0021]

According to the dust collection efficiency monitoring method of the present invention, the dust collection efficiency of the ionization section or the dust collection section can be measured each time the air purifier is turned ON / OFF, and the deterioration of the dust collection efficiency is monitored almost every day. As a result, the proper cleaning or replacement time can be indicated to the outside. As a result, the air purifier can always be used while maintaining a certain capacity or more, and economically efficient cleaning or replacement can be performed.

When the soft method is used, by re-storing the conversion table for determining the reference value, it is possible to deal with various air purifiers with the same circuit configuration, and it is possible to reduce the unit cost of the device. Become. Further, since the sampling conditions can be adjusted and changed by software, it is possible to easily change the measurement error and the reference value due to the deterioration of the device, and to extend the usable period. In addition, in a soft method, the CPU can directly display the dust collection efficiency as a specific number.

On the other hand, when the hard method is used, it is the same as the soft method that the reference value is changed according to the conversion table for determining the reference value so as to have versatility. Adjusting and changing the sampling conditions is less flexible than the soft method, but since the entire device can be downsized,
It is also possible to incorporate it into a smaller air purifier to make an integrated product, and it is possible to improve the added value of the air purifier.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram in which a discharge circuit is processed by a soft method.

FIG. 2 is a circuit configuration diagram for processing a discharge circuit by a hardware method.

FIG. 3 is a graph showing the relationship between dust collection efficiency and discharge voltage.

FIG. 4 is a circuit configuration diagram in which a charging circuit is processed by a soft method.

FIG. 5 is a circuit configuration diagram for processing a charging circuit by a hardware method.

[Explanation of symbols]

 1 Air Purifier 2 Dust Collection Part 4 Ionization Part 5 High Voltage Generation Circuit 7 Voltage Conversion Circuit 8 CPU 9 A / D Conversion Circuit 10 Latch Circuit 11 Timer 12 Voltage Comparison Circuit 13 Reference Voltage Generation Circuit

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Eiichi Ozawa 5-3-8 Shiba, Minato-ku, Tokyo Within Mitsubishi Motors Corporation (72) Inventor Hiroshi Motomi 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Co., Ltd. (72) Inventor Yasukichi Akamatsu 1410 Shimohira, Kasaoka, Okayama Prefecture Hirta Industrial Co., Ltd. Junji Ishii, 1410 Shimohira, Kasaoka, Okayama Prefecture, within the Hirta Industrial Co., Ltd. (72) Inventor, Masaaki Miyake, 1410, Mohei, Kasaoka, Okayama, within the Hirta Industrial Co., Ltd. 958 Address Takayoshi Sangyo Co., Ltd. (72) Inventor Masakatsu Iwamoto 958 Ikeuchi, Kana-gun, Kagawa-gun, Kagawa-gun

Claims (3)

[Claims] 1. An air purifier comprising an ionization part and a dust collection part, which detects the dust collection efficiency of the purifier or its deterioration by measuring the circuit characteristics in which the ionization part or the dust collection part is configured as a capacitor. A method for detecting deterioration of dust collection efficiency in an air purifier. 2. An air purifier comprising an ionization section and a dust collection section, wherein a high voltage generation circuit is connected to a discharge circuit or a charging circuit in which the ionization section or the dust collection section is configured as a capacitor, and the ionization section or the dust collection section is connected. Dust collection in an air purifier that detects the dust collection efficiency of the ionization unit or dust collection unit or its deterioration by digitizing the discharge characteristic or charge characteristic of the unit and sampling to the CPU and comparing the sample value with the reference value. Method of detecting deterioration of efficiency. 3. An air cleaner comprising an ionization part and a dust collection part, wherein a high voltage generation circuit is connected to a discharge circuit or a charging circuit in which the ionization part or the dust collection part is configured as a capacitor, and the ionization part or the dust collection part is collected. A method for detecting deterioration of dust collection efficiency in an air purifier, which detects the dust collection efficiency of an ionization section or a dust collection section or its deterioration by comparing the discharge voltage or charge voltage of the section with a reference value.