JPH10148200A - Simplified air-cleaning filter and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove pollen, etc., in air by utilizing an electric fan to clean indoor air. SOLUTION: In this constitution, a synthetic fiber electret nonwoven fabric 11; composed of a polyolefine fiber having a surface charge density of at least 5×10<-11> coulomb/cm<2> , a mean weight fiber diameter of less than 50μm, and a METSUKE of 2-200g/cm<2> , and manufactured by a melting blow method; is adopted as an internal insulation, and an electric fan mounting means is fitted. This filter features high purifying effect because a fine particle such as floating follen is electrically attracted, caught, and removed when feeding air contacts an electret fiber for composing the nonwoven fabric. Consequently, the filter can be used by opening small ventilating holes in the internal insulation to relax resistance to the transmission of air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes a simple air purifying filter mounted on a fan for capturing and removing minute suspended matters floating in the air, and a fan for easily purifying air. The present invention relates to a simple air cleaning method.

[0002]

2. Description of the Related Art If it is possible to easily purify air using a fan, it is convenient and very useful.
Various types of filters, such as the fan filter described in Japanese Utility Model Application Laid-Open No. 61-19698, the fan cap described in Japanese Utility Model Application Laid-Open No. 62-126593, the fan described in Japanese Utility Model Application Laid-Open No. 2-69096, and the like. Air cleaning means have been proposed.

[0003]

Recently, in addition to air pollution in urban areas, so-called hay fever has spread nationwide, so that fine particles that easily float in the air using a fan or the like can be removed. There is a growing need for devices and methods that can be captured and cleaned. However, filters that are effective at removing fine particles have a large resistance when air passes through the filter, and when installed in the ventilation path of an electric fan, the amount of air passing therethrough decreases dramatically, and the amount of air that bypasses the filter Became dominant and could not achieve a sufficient cleansing effect. In the end, many attempts to keep indoor air clean using a portable and simple device such as a fan have been offered as ideas, but they have not been embodied and used in daily use. As a result of the research, the present inventor has completed a practical apparatus and method that can easily realize a clean living space using a fan, and provides the apparatus and method.

[0004]

The present invention will be described with reference to the drawings. FIG. 1 is a plan view of an embodiment of a simple air cleaning filter of the present invention, FIG. 2 is a front view thereof, and FIGS. 3 and 4 are perspective views of embodiments of the simple air cleaning filter of the present invention. .

[0005] The present invention provides that the surface charge density is at least 5x.
A simple air purifying filter, comprising: a synthetic fiber electret nonwoven fabric having 10 ^-11 coulomb / cm ^2; and means for mounting the nonwoven fabric on a fan. The synthetic fiber electret nonwoven fabric used in the present invention has a weight average fiber diameter of 100 μm.
m, the basis weight is ² to 200 g / m ² , and a nonwoven fabric made of a polyolefin fiber produced by a melt blow method can be preferably used. further,
The synthetic fiber electret nonwoven fabric may be used by forming small holes for ventilation. In the present invention, as means for attaching the synthetic fiber electret nonwoven fabric to the electric fan, for example, the nonwoven fabric may be fixed to a frame formed in a pot bottom shape and attached to the electric fan.

Further, according to the present invention, any one of the above filters for simple air cleaning is mounted on a front guard portion and / or a rear guard portion of an electric fan, and the air to be blown is brought into contact with the synthetic fiber electret nonwoven fabric for cleaning. A simple air cleaning method is provided. The contact between the air and the synthetic fiber electret nonwoven fabric can be realized by allowing the air to pass through the synthetic fiber electret nonwoven fabric or to flow along the surface of the synthetic fiber electret nonwoven fabric.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A simple air cleaning filter and a simple air cleaning method of the present invention will be specifically described. The present invention combines a fan and a filter using a synthetic fiber electret nonwoven fabric as a filter medium, and pollen floating in the air by allowing room air to pass through the filter medium or circulate in contact with the filter medium without passing through. And the like to capture the amount of fine particles and reduce the concentration thereof. However, the present invention is for the purpose of purifying air, and cooling air from a fan cannot always be expected.

In the simple air cleaning filter of the present invention, the filter is permanently polarized positively and negatively to form an electric field around the filter, and has a surface charge density of at least 5 × 10 ^-11 coulomb / cm ²
The nonwoven fabric made of the synthetic fiber electret is used as a filter medium. Generally, in a synthetic fiber electret nonwoven fabric, the more efficiently the polarized structure is highly arranged in the thickness direction, the higher the collection efficiency of fine particles. The surface charge density of the electretized nonwoven fabric used in the present invention is at least 5 × 10 ⁻¹¹ coulomb / cm ² , preferably 1 × 1.
This is a level exceeding 0 ^-10 coulomb / cm ² . The higher the surface charge density is, the more preferable it is. When the surface charge density is 5 × 10 ⁻¹¹ coulomb / cm ² or less, there is no great difference from the conventional filter in the performance of capturing fine particles depending on the use conditions.

According to the knowledge of the present inventors, the upper limit of the surface charge density value is set to about 5 × 10 ⁸ coulomb / cm ^{2, in} order to stably perform electret processing.
It is also practical from the point of view of the sufficient effect of capturing minute suspended matter.

As the fiber material constituting the fiber electret, polyolefin fibers, especially polypropylene fibers, are preferred. Polypropylene fibers have chemical resistance and are characterized by being easily electretized. For the purposes of the present invention, fibers having a weight average fiber diameter not exceeding 100 μm are used. Practically, the range of 2 to 50 μm is preferable. Generally, those manufactured by melt-blowing spinning are preferred. Non-woven fabric can be obtained by any suitable means, for example,
It can be made into an electret by using a method described in JP-A-102476 (electret processing and sheet manufacturing method).

The basis weight of the electret nonwoven fabric used in the present invention is preferably in the range of ^{2 to} 200 g / m ² , and particularly preferably 5 to 200 g / m ^2.
Range to 100 g / m ² is preferred. In general, with the same basis weight, the thinner the fiber, the larger the surface area and the higher the collection efficiency of the filter for fine particles, and the larger the thickness, the smaller the pressure loss. For fibers of the same thickness, the greater the basis weight, the higher the collection efficiency, but the greater the pressure loss.

When the resistance of the filter medium is large, the filter medium can be used with a reduced basis weight or with a number of small holes for ventilation. The synthetic fiber electret nonwoven fabric not only prevents the passage of fine particles by a certain thickness and a compact structure like a conventional filter medium, but also, in addition, air blown by a fan constitutes the nonwoven fabric. It is considered that when contacting the electretized fibers, microparticles such as pollen floating in the air are electrically sucked, captured, and removed.

On the other hand, the blowing pressure of the electric fan is not usually large. Even if the filter medium is simply attached, air may leak from the surroundings or make noises without passing through the filter medium due to the large resistance of the filter medium to the blowing. This problem can be solved by fixing it inside a duct like a ventilation fan, but it is not realistic to attach a ventilation duct to the fan for use for the original purpose of the fan or for the purpose of the present invention. Nor is it easy. By the way, the filter device of the present invention is characterized in that the entire amount of air including fine particles does not necessarily need to pass through the filter medium. Therefore, it is possible to use the filter medium by opening small holes for ventilation, generally many small holes for ventilation. The term “small holes” as used herein does not refer to voids formed between the constituent fibers of the nonwoven fabric, but small holes having a larger pore diameter than the voids, and generally 50 to 100 m.
If it is a small hole of about m, one or more, if it is a small hole of several mm to several tens of mm, a large number of holes may be provided,
It refers to a hole especially opened for ventilation holes related to the blowing characteristics of a fan. By opening such small holes for ventilation in the filter medium, some air flows to the small holes along the surface of the filter medium, during which it is sucked and captured by the synthetic fiber electret nonwoven fabric as the filter medium, and The resistance of the filter medium to the blowing is reduced. The optimal diameter and distribution of pores are determined by the performance of synthetic fiber electret nonwoven fabric, ventilation performance,
What is necessary is just to determine in consideration of the balance with the blowing property as a fan, etc.

[0014] The simple air cleaning filter of the present invention comprises the electret nonwoven fabric and a means for supporting the filter medium and mounting it on a fan. Usually, the filter is mounted such that a portion of the electret nonwoven is located along the outside and / or inside of the guard on the front or back of the fan. In general, there is a situation that it is easy to attach, and in many cases, it is attached to the outside of the front guard on the blower side, and the inner surface of the rear guard on the suction side can be avoided from a safety point of view. Although there is no particular limitation on the mounting means, a fan having the electret nonwoven fabric 11 fixed to a frame 12 which can be easily mounted on the guard of the fan is mounted on the fan, or a fastener 22 is mounted on the electret nonwoven fabric 21 to attach the fan 22 to the fan. Fastened to a guard or, for example, electret nonwoven fabric on the front side and a net (net or mesh) on the back side
Means such as preparing the bag constituted by 34 and covering it with a guard is preferable.

In order to fix the electret non-woven fabric 11 in accordance with the guard of the electric fan, the non-woven fabric 11 is fixed by using the frame 12, for example, a plastic belt which is deformed flexibly and has high shape retention, a paper tape containing a soft wire, or the like. The center part formed by using the pan-shaped bottom frame 12,
The electret nonwoven fabric 11 is attached. The peripheral portion of the frame body can be sandwiched between, for example, a front guard and a rear guard of the electric fan so that the air sent by the electric fan passes through the electret nonwoven fabric, and the frame can be tightly fixed.

Further, a fastener 22 such as a hook may be directly or indirectly attached to the peripheral portion 24 of the electret nonwoven fabric 21 and attached to a guard or the like. For example, if the hook 22 is fixed to a guard via a rubber string or a spring 23, it can be easily attached and detached and securely fixed. A bag-shaped fan-mounted filter comprising an electret nonwoven fabric or an electret nonwoven fabric 31 and a net 34 and having an opening 32 may be used to cover the guard from the front side of the fan with the opening side on the back side.
It is preferable to attach a string or a rubber string around the opening 33 so that the opening 33 can be squeezed or opened to be attached to the electric fan.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The simple air purifying filter of the present invention is mounted on a rear guard of a fan and used indoors to confirm the effect. Example 1 A simple air purifying filter made of a synthetic fiber electret nonwoven fabric having a weight average fiber diameter of about 8 μm, a thickness of about 0.25 mm, and a basis weight of about 20 g / m ² was attached to a back guard of a fan, and the indoor air filter was installed. The microparticles floating in the air were captured and separated over time. Table 1 shows the measurement results of the particles captured and separated by the filter.

Comparative Example 1 The same synthetic fiber electret nonwoven fabric as used in Example 1 was allowed to stand for 9 hours in the same room at the same time as in Example 1, and the particles separated and captured were measured. Table 1 shows the results.

Example 2 A simple air purifying filter made of a synthetic fiber electret nonwoven fabric having a weight average fiber diameter of about 3 μm, a thickness of about 0.15 mm, and a basis weight of about 20 g / m ² was attached to the back guard of a fan. As in Example 1, the particles were used in a room for 9 hours to capture and separate fine particles floating in the air. Table 1 shows the measurement results of the particles captured and separated by the filter.

Comparative Example 2 The same synthetic fiber electret nonwoven fabric as used in Example 2 was allowed to stand for 9 hours in the same room at the same time as in Example 2, and the particles captured and separated were measured. Table 1 shows the results.

[0021]

[Table 1]

[0022]

The filter for simple air cleaning of the present invention is
By using a synthetic fiber electret nonwoven fabric as a filter medium, it is possible to capture pollen and other fine particles with a small pressure loss, so that it can be installed in a fan to easily clean air in rooms and the like. A fan using the present invention is extremely convenient because it can move to an arbitrary room or the like and clean the room. In addition, since the present invention has a very simple configuration, the price is low, and attachment / detachment and replacement are easy.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1;

FIG. 3 is a perspective view of an embodiment of the present invention.

FIG. 4 is a perspective view of an embodiment of the present invention.

[Explanation of symbols]

11, 21, 31: Electret nonwoven fabric (filter material) 12: Frame 21: Filter 22: Fastener (hook) 23: Rubber string 24: Peripheral part 31: Filter
32: Opening 33: Around the opening (elastic string) 34: Net (mesh,
Net)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Mikio Jinno, Inventor 2-9-29 Kamimaezu, Naka-ku, Nagoya-shi, Aichi Tsuchi Indoor Co., Ltd. No. 3 Toray Industries, Inc. Osaka Works (72) Inventor Masami Nakano 3-3-1 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Toray Industries, Inc. Osaka Works

Claims (5)

[Claims] 1. A simple air cleaning system comprising a synthetic fiber electret nonwoven fabric having a surface charge density of at least 5 × 10 ^-11 coulomb / cm ² and means for mounting the nonwoven fabric on a fan. filter. 2. The synthetic fiber electret nonwoven fabric according to claim 1,
The weight average fiber diameter does not exceed 100 μm, and the basis weight is 2 to 20.
A 0 g / m ^2, a simplified air cleaning filter according to claim 1, characterized in that it consists of polyolefin fibers non-woven fabric produced by a melt blow method. 3. The synthetic fiber electret nonwoven fabric according to claim 1,
3. A simple air purifying filter according to claim 1, wherein a small hole for ventilation is provided. 4. A method according to claim 1, wherein the means for attaching the nonwoven fabric to the electric fan is a frame formed in the shape of a pot bottom, and the nonwoven fabric is fixed to the frame. Simple air purifying filter. 5. A simple air purifying filter according to claim 1, wherein said filter is a front guard of a fan and / or
Alternatively, a simple air cleaning method is provided in which the air to be blown is attached to a back guard portion and the air to be blown is brought into contact with the synthetic fiber electret nonwoven fabric to clean the air.