JPH0679195A - Air cleaner - Google Patents

Abstract

PURPOSE:To provide an air cleaner for improving the dust collection effect without decreasing the blasting volume into a clean room or the like. CONSTITUTION:An air cleaner comprises a fan 1 provided with an impeller 3 disposed rotatably in a case 2, an air filter 4 disposed on the suction opening of the fan 1, a static filter 5 and the like disposed on the blasting opening side of the fan 1 and a power source device 6 for charging the static filter 5 and other electric surfaces by applying the voltage to the static filter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air cleaner having high dust collection efficiency.

[0002]

2. Description of the Related Art An air cleaning system used in a clean room or the like has, for example, an air filter (HEPA filter) arranged at a blower opening of a ceiling duct to blow the sucked outside air into the room through the air filter and to air-condition Air is circulated in the room through the machine, and dust is collected by the air filter in the process of this circulation.

In the case of a HEPA filter, for example, an air filter can capture dust having a particle size of 0.3 to 0.5 μm or more, but finer dust can be collected if the filter has a fine mesh. Therefore, the cleanliness of the room can be further improved. HEP
If a ULPA filter with a finer mesh than the A filter is used, dust of 0.1 μm or more can be captured.

However, if a fine air filter such as a ULPA filter is used, the air resistance applied to the air filter becomes large, and the desired air flow cannot be obtained.
On the contrary, the dust collection efficiency is reduced. Therefore, it is not always necessary to use a fine filter as the air filter to be attached.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems existing in the prior art. In a clean room or the like, the dust collection efficiency can be improved without reducing the amount of air blown into the room. The purpose is to raise.

[0006]

In order to solve the above problems, the air cleaner of the present invention focuses on a certain phenomenon. Generally, when an air filter is attached to the suction port side of a fan to drive the fan to collect dust, soot-like dust adheres to the impeller surface of the fan over time. This is because the plastic impeller is electrostatically charged and dust is electrostatically adsorbed to the impeller surface by the electrostatic charge, and the phenomenon that the plastic surface is sooted even in the clean room is observed. A prominent example of this electrostatic attraction is the adhesion of dust to the rear surface of the cathode ray tube in a television receiver.

The present invention positively utilizes the above phenomenon,
By arranging an air filter and an electrostatic filter on the suction port side and the ventilation port side of the fan, respectively, dust is electrostatically adsorbed on the surface of the electrostatic filter charged to a high potential, and the amount of air blown into the room is reduced. The present invention provides an air purifier that can improve dust collection efficiency without the need.

[0008]

[Operation] In addition to the dust collecting action of the electrostatic filter being added to the dust collecting action of the air filter, the dust collecting effect is further enhanced, and the desired dust collecting action is achieved without using a fine filter. Dust can be done. Therefore, since it is not necessary to make the filter fine, there is no need to reduce the amount of air blown into the room, the conventional problems can be solved, and the dust collection efficiency can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an air purifier according to the present invention is shown in FIG.
It will be described with reference to FIGS. FIG. 1A is a schematic sectional view of an air cleaner according to the present invention. In FIG. 1A, 1 is a fan, for example, 120 mm × 120
It is configured by internally mounting an impeller 3 which is self-excitedly rotated in a square cylindrical case 2 of mm, and the rotation of the impeller 3 causes an air flow in an axial direction around the impeller 3 to occur. An air filter (HEPA filter) 4 is arranged on the suction inlet side of the fan 1.
Further, the electrostatic filter 5 is arranged on the discharge port side of the fan.

The electrostatic filter 5 is used by connecting a power source device (for example, a flyback transformer) 6 to the electrode portion and charging the surface to a high potential. Reference numeral 7 denotes an insulating guard, which serves as a protective cover for preventing an object from directly touching the charged electrostatic filter 5.

FIG. 1 (b) is a graph showing the degree of dust collection when air passes through the air cleaner of FIG. 1 (a) in an easy-to-understand manner. The vertical axis represents the dust particle size. It represents. The air filter (HEPA filter) 4 is 0.
Since dust with a particle size of 3 μm or more can be captured, the air passing through the inside of the fan has a particle size smaller than that, and the particle size is further reduced by passing through the electrostatic filter 5 next.

As shown in FIG. 2, the electrostatic filter 5 is a net-like assembly of electrode rods 8 made of copper or the like. As shown in FIG. 3, the surface of the electrode rods 8 is coated with a ferroelectric film 9. In addition to facilitating charging, the surface area provided for electrostatic adsorption is increased. As a ferroelectric material forming the ferroelectric film 9, vinyl chloride is preferable because it is inexpensive and easily charged, but there is no problem even if other materials are used.

In the air cleaner having such a structure,
The power supply device 6 charges the electrostatic filter 5, and the fan 1
When the air is driven, external air is sucked and passes through the air filter 4, dust in the air is captured, and air discharged from the fan 1 passes between the electrode rods 8 of the electrostatic filter 5 and the fine air in the air is discharged. Dust is electrostatically adsorbed on the electrode surface. As a result, even though the HEPA filter is used as the air filter 4, it is possible to obtain a dust collecting effect equal to or higher than that of the ULPA filter.
Even if a fine filter is not used, the dust collection performance will be significantly improved.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 4 shows an electrostatic filter 10 arranged on the blower port side of the fan 1, in which a large number of strip-shaped electrode plates 11 such as blinds are arranged in parallel, and a ferroelectric film is formed on these surfaces. 9 is a coating-treated product.

In the past, an electric dust collector has existed for a long time, but this device supplies an extra-high voltage DC voltage between the discharge electrode (-) and the dust collector electrode (+) so that the surrounding area of the discharge electrode is high. The gas is locally dielectrically broken down to generate a so-called corona discharge, and particles in the air passing between the electrodes are forcibly charged (-) to be collected on the dust collecting electrode. It is completely different from the electric filter. Further, the air purifier of the present invention can be applied not only to a clean room, but also to a room requiring a clean environment such as for medical purposes, and can be adapted to various fan sizes.

[0016]

As described above, the air cleaner of the present invention is equipped with not only the air filter but also the electrostatic filter, and positively utilizes the electrostatic adsorption phenomenon of dust on the charged surface of the plastic. Since it is configured, it is possible to capture dust that is smaller than the dust that can be captured only by the air filter, and it is possible to collect dust without reducing the air flow rate, which can greatly improve dust collection efficiency. Is.

[Brief description of drawings]

FIG. 1 shows an embodiment of an air cleaner of the present invention, (a)
Is a schematic cross-sectional view, and (b) is an explanatory diagram of dust collecting characteristics.

FIG. 2 is an enlarged perspective view showing a part of the electrostatic filter of FIG.

FIG. 3 is a cross-sectional view of an electrode rod forming the electrostatic filter of FIG.

FIG. 4 is an enlarged perspective view showing another example of the electrostatic filter of FIG.

[Explanation of symbols]

 1 Fan 2 Case 3 Impeller 4 Air Filter (HEPA Filter) 5, 10 Electrostatic Filter 6 Power Supply Device 7 Insulating Guard 8 Electrode Rod 9 Ferroelectric Film 11 Electrode Plate

Claims (4)

[Claims] 1. A fan having an impeller rotatably provided in a case, an air filter arranged on the suction port side of the fan, an electrostatic filter arranged on the blower port side of the fan, and the static filter. A power supply device for applying a voltage to an electric filter to charge the electrode surface of the electrostatic filter. 2. The air purifier according to claim 1, wherein the electrode portion of the electrostatic filter is constructed by assembling electrode rods in a net shape. 3. The air cleaner according to claim 1, wherein the electrode portion of the electrostatic filter is formed by arranging a large number of strip-shaped flat plates in parallel. 4. The air purifier according to claim 1, wherein the surface of the electrode portion of the electrostatic filter is coated with a ferroelectric film.