JP2005021788A - Air cleaning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce discharge sound or noise of an air cleaning apparatus which collects dust and deodorizes odor by discharge. <P>SOLUTION: This air cleaning apparatus is provided with: a discharge electrode 2 and a counter electrode 3; and a high-frequency, tiny pulse width, high voltage application device 4 which applies the high voltage of the high-frequency tiny pulse width between both electrodes. The thickness of the discharge electrodes is adjusted to be 1.0 to 2.0 mm. This prevents resonance due to pulse voltage application. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air purifying apparatus that reduces abnormal noise generated in a purifying apparatus that removes harmful substances, odor components and dust in air, destroys or inactivates microorganisms by discharging.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an air purification device using electric discharge applies a DC high voltage between electrodes installed in an air flow path to charge dust and collect dust at a collector installed at the rear, or to apply DC high voltage + By applying a pulsed voltage and generating a corona discharge while maintaining the dust collection performance, the odorous substance is decomposed by the oxidation reaction of radicals to purify the air (for example, Patent Document 1). reference).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-51735
[Problems to be solved by the invention]
However, the energy of the corona discharge generated by the above conventional method is such that the current value at the time of voltage application is about several hundreds to several thousand μA, so the pulse width is as wide as about several tens μs and the energy of discharge is small, so deodorization The performance and dust collection performance are very small. Moreover, it is more difficult to remove harmful substances and to kill or inactivate microorganisms / viruses that require a discharge with higher energy, and sufficient air purification cannot be performed. Therefore, a high voltage with a very small pulse width at a high frequency is applied to the discharge electrode to generate much larger energy than the energy of corona discharge, greatly improving the conventional deodorizing performance, removing harmful substances, It will be possible to reliably destroy and inactivate viruses. However, when a pulse voltage as described above is applied between the electrodes and discharged, a discharge sound is generated, and there is a problem that it is very uncomfortable when operated indoors. SUMMARY OF THE INVENTION An object of the present invention is to provide an air purification device that reduces discharge noise generated in a purification device that discharges harmful substances, odor components and dust in the air, destroys microorganisms, or inactivates them by discharging. It is what.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the air purifying apparatus according to the first aspect of the present invention is a high-voltage applying device for disposing a counter electrode on both sides of a discharge electrode and applying a high voltage for generating a discharge between the electrodes. The thickness of the discharge electrode is 1.0 to 2.0 mm.
[0006]
In the air purifying apparatus according to the second aspect of the present invention, L ≧ a, where L is the distance between the protrusions and a is the bottom of the protrusion.
[0007]
According to a third aspect of the present invention, there is provided an air purification apparatus of the present invention in which the both ends of the discharge electrode are not electrically connected.
[0008]
Here, the high frequency minimum pulse width high voltage application device includes, for example, a switching circuit such as an IGBT in the voltage doubler circuit, generates a voltage having a high frequency pulse waveform, and further boosts the voltage with a high voltage transformer. This is an electrical circuit that applies a high voltage with a pulse width, and the type thereof is not limited at all.
[0009]
In order to kill or inactivate microorganisms and viruses, it is important to generate a discharge called a streamer discharge having a high discharge energy among corona discharges. In order to efficiently generate radicals within a specific spatial distance, a method of applying a pulse waveform voltage is most suitable. In order to apply energy sufficient to kill or inactivate microorganisms and viruses, it is better to shorten the pulse width because the energy level increases, and it is preferable to shorten the pulse width to about 1 μsec or less. The voltage varies depending on the distance between the discharge electrode and the counter electrode. By making the applied voltage into a pulse shape, the rise time becomes steep from 0 V to a high voltage, the movement of ions between electrodes is reduced, and electrons that collide with molecules and create ions and radicals can be accelerated efficiently.
[0010]
Microorganisms and viruses destroy outer walls by collision of accelerated electrons, ions, radicals, etc. generated by streamer discharge, and also destroy DNA and RNA. In addition, since the discharge electrode has protrusions, the discharge energy concentrates on the protrusions, and streamer discharge having higher energy than that of the prior art can be obtained. This can increase the number of collisions of electrons, ions, radicals, etc. when air containing microorganisms and viruses passes through the discharge region, and can sufficiently destroy or inactivate microorganisms and viruses, improving air purification efficiency. To do. In addition, the harmful substances and odor components can be decomposed by a synergistic effect of electrons, ions, radicals and the like generated by the streamer discharge. It is also possible to collect electric dust by applying a positive pulse or negative pulse between the electrodes to charge the dust and then collecting it with a reverse-potential collector electrode or electric filter installed behind. .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The air purifying apparatus according to the first embodiment of the present invention is an air purifying apparatus provided with a high voltage applying apparatus for disposing a counter electrode on both sides of a discharge electrode and applying a high voltage for generating a discharge between the two electrodes. In this case, the discharge electrode having a thickness of 1.0 mm to 2.0 mm allows a high frequency minimum pulse to apply a high voltage having a minimum pulse width of a high frequency between the discharge electrode provided with the protrusion, the counter electrode, and the electrode. A streamer discharge with stable high energy is obtained by applying a voltage with a wide high voltage application device, and when air containing harmful substances or microorganisms passes through the discharge part, it is caused by ions, radicals, accelerated electrons, etc. The outer wall of microorganisms and viruses can be destroyed, DNA and RNA can be destroyed, air purification efficiency can be improved, and the discharge noise generated by streamer discharge can be reduced. That.
[0012]
【Example】
An embodiment of the present invention will be described below with reference to the drawings.
[0013]
(Example 1)
In FIG. 1, 1 is an air purification device, 2 is a discharge electrode, 3 is a counter electrode, 4 is a high frequency minimum pulse width high voltage application device, 5 is a positive electrode, 6 is a ground or negative electrode, and 7 is an airflow passage region. is there.
[0014]
2 is a cross-sectional view of FIG. 1, wherein 8 is an air purification device upstream airflow, 9 is an air purification device downstream airflow, and 10 is a discharge region.
[0015]
FIG. 3 is an enlarged side view of the electrode portion.
[0016]
The operation of the above configuration will be described below.
[0017]
The air purification apparatus 1 includes a discharge electrode 2 and a counter electrode 3. The plus electrode 5 of the high frequency minimum pulse width high voltage application apparatus 4 is connected to the discharge electrode 2, and the ground or minus electrode 6 is connected to the counter electrode 3. The streamer discharge is performed in the discharge region 10 by applying a high frequency minimum pulse width high voltage to the discharge electrode 2 by the high frequency minimum pulse width high voltage applying device 4.
[0018]
The generation mechanism of this streamer discharge is that electrons are created by the ionization of neutral molecules in front of the avalanche of electrons, which causes the next new avalanche, and these avalanches merge one after another, and the avalanche progresses at high speed. And most of the current is due to electrons.
[0019]
Electrolysis between the discharge electrode 2 and the counter electrode 3 has a significant electric field concentration in the vicinity of the discharge electrode 2, so that if the voltage is sufficient, a large amount of ions and photons are produced by avalanche electrons. By using the discharge electrode 2 as a positive electrode, a large amount of photons are emitted in all directions near the discharge electrode 2 and absorbed by neutral molecules in the vicinity. An avalanche is formed and flows out into positive ions to form a plasma column. In this case, negative ions and positive ions toward the earth are concentrated at the high density on the front of the plasma, and in addition to electric field concentration, a particularly strong electric field is formed between the space charge and the space charge of the new electron avalanche group that scatters, This further promotes light emission.
[0020]
Since the above is performed in the discharge region 10, when the air flow is passed through the air purification device upstream air flow 8 and the air purification device downstream air flow 9 in the discharge region 10, microorganisms and viruses are included in the air purification device upstream air flow 8. In the discharge region 10, the outer wall and protein are destroyed by high-speed scattering of ions, radicals, accelerated electrons, and the like while the microorganisms pass through the discharge region 10. Furthermore, DNA and RNA are deformed, that is, microorganisms and viruses are destroyed or inactivated during passage and pass to the downstream airflow 9.
[0021]
However, in order to reliably destroy or inactivate microorganisms and viruses during the passage in the discharge region 10, the discharge when the air flow is passed as in the air purification device upstream air flow 8 and the air purification device downstream air flow 9. The relationship between the passing air speed of the air flow in the region 10 and the pulse frequency for applying a high voltage is important. That is, before the microorganisms pass through the discharge region 10, a high voltage must be applied at least once and the outer wall and protein must be destroyed by high-speed scattering of a large amount of electrons.
[0022]
For example, in an air conditioner or the like, the wind speed of the airflow passing through the air conditioner indoor unit is about 1 m / s. When the width of the discharge region 10 is several mm to several tens mm, it is necessary to apply a high voltage at a high frequency of several hundreds to several kHz.
[0023]
In order to cause a larger amount of electrons to be scattered at high speed, it is advantageous to raise the voltage instantaneously, and the generation of ozone harmful to the human body can be reduced if the voltage application time is shorter. That is, it is necessary to apply a high voltage with a minimum pulse width.
[0024]
As described above, according to the configuration described above, the discharge pulse 2 and the counter electrode 3 are considered to have a minimum pulse width that increases the voltage instantaneously and reduces the generation of ozone by the high frequency minimum pulse width high voltage application device 4. Although it is necessary to apply a high voltage with a very small pulse width at a high frequency, in order to satisfy the three conditions, the circuit becomes very complicated and large. Therefore, even when a gas containing harmful substances, microorganisms or viruses passes between both electrodes at a very high speed, the protrusion 11 is formed so that the number of collisions between the microorganisms and ions, radicals, accelerated electrons, etc. caused by discharge can be increased. By applying a high voltage and a high voltage with a minimum pulse width to the provided discharge electrode 2, it becomes possible to generate a streamer discharge having stable high energy. That is, when harmful substances, microorganisms, and viruses in the air pass through the discharge region 10, the number of collisions of electrons, ions, radicals, etc. due to discharge increases, and the air purification effect in one pass can be improved. . However, when the thickness of the discharge electrode 2 is small, resonance occurs due to vibration of streamer discharge generated by application of a pulse voltage, and discharge noise is generated. Therefore, the optimum thickness was examined while varying the thickness of the discharge electrode 2. The discharge was performed at a frequency of 2 kHz, a pulse width of about 1 μsec, and a voltage of 5 kv. The discharge energy becomes larger when the discharge electrode is made thinner. However, due to the disadvantage that the strength becomes weaker, it becomes easier to cut or weakens against corrosion, so if it is made thinner, careful examination is necessary depending on the usage conditions. However, when the condition is 1.0 to 2.5 mm, resonance hardly occurs and the discharge sound is lowered. Moreover, as the thickness increases, the discharge energy greatly decreases, and the degradation performance of harmful substances and microorganisms decreases.
[0025]
(Example 2)
Another embodiment will be described with reference to FIG. A discharge electrode 21 is provided with a substantially triangular projection 11 for increasing the energy of the streamer discharge, and has an action of concentrating the discharge energy when a pulse voltage is applied. The arrangement interval is arranged with an interval of L ≧ a, where a is the length of the bottom side of the protrusion 11. Other configurations are the same as those in the first embodiment. Further, this operation can remove harmful substances and sterilize air containing microorganisms and viruses in the same manner as in the first embodiment, but a plurality of intervals are installed at intervals longer than the length of the bottom side of the protrusion 11. As a result, it is possible to obtain a discharge in which the adjacent streamer discharges do not overlap with each other. As a result, streamer discharge with low input voltage and high efficiency can be obtained. Decomposition of harmful substances and odor components, microorganisms and viruses It becomes possible to sterilize. By disposing the protrusions 11 on the discharge electrode 21 with an interval of L ≧ a, the discharge sound generated by resonance due to the vibration of the streamer discharge is lowered.
[0026]
Example 3
Another embodiment will be described with reference to FIG. Reference numeral 22 denotes a discharge electrode. The discharge electrode 22 is made of a single wire made of stainless steel or tungsten, and is routed between a plurality of opposed electrodes 3. A pulse voltage is applied from one of the discharge electrodes 22, and the other Is fixed so that it is not electrically connected to anything. In this way, the generation of TV noise can be reduced by applying the pulse voltage after being fixed. The discharge electrode 22 was electrically connected at both end faces to form a loop, and an experiment was conducted with a discharge condition of a frequency of 2 kHz, a pulse width of about 1 μsec, and a voltage of 5 kv. However, those that did not connect in a loop were not abnormal in each channel.
[0027]
【The invention's effect】
As is clear from the above embodiment, in the air purification apparatus provided with a high voltage application device for disposing a counter electrode on both sides of the discharge electrode and applying a high voltage for generating a discharge between the two electrodes, By changing the thickness from 1.0 mm to 2.0 mm, as a result, resonance due to application of a pulse voltage is less likely to occur, and the discharge sound is reduced.
[0028]
Further, by disposing the protrusions on the discharge electrode with an interval of L ≧ a, it is possible to further reduce the discharge sound generated by resonance due to the vibration of the streamer discharge.
[0029]
Also, wire-like discharge electrodes are routed between a plurality of opposed electrodes, a pulse voltage is applied from one of the discharge electrodes, and the other is fixed so that it is not electrically connected to any other place. As a result, it is possible to reduce discharge noise and further reduce TV noise.
[Brief description of the drawings]
FIG. 1 is a front view of an air purification apparatus according to the present invention. FIG. 2 is a cross-sectional view of the air purification apparatus of the present invention. FIG. 3 is an enlarged view of a side surface of an electrode section. FIG. 5 is a front view of the second air purification device.
DESCRIPTION OF SYMBOLS 1 Air purification apparatus 2, 21, 22 Discharge electrode 3 Counter electrode 4 High frequency minimum pulse width high voltage application apparatus 5 Positive electrode 6 Ground or minus electrode 7 Airflow passage area 8 Air purification apparatus upstream airflow 9 Air purification apparatus downstream airflow 10 Discharge Region 11 protrusion

Claims (3)

In an air purifying apparatus in which a counter electrode is provided on both sides of a discharge electrode and a high voltage applying device for applying a high voltage for generating a discharge is provided between both electrodes, the thickness of the discharge electrode is 1.0 mm to 2.0 mm. An air purification device characterized by 2. The air purifier according to claim 1, wherein L ≧ a, where L is an interval between the protrusions and a is a base of the protrusions. The air purifier according to claim 1 or 2, wherein both ends of the discharge electrode are routed so as not to be electrically connected.

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