JPH04108511A - Air cleaning filter - Google Patents

Abstract

PURPOSE:To obtain a filter low in pressure loss and strong against falling or bending by filling a large number of the cells of a core material with an adsorbent such as granulated activated carbon and bonding reticulated air permeable sheets to both surfaces of the core material and integrating the whole by a rigid frame. CONSTITUTION:A honeycomb-shape core material 1 consisting of a large number of cells 5 is formed by a method wherein thin aluminum plates are bent to be bonded by an adhesive such as a phenolic resin and, after the adhesive is lightly cured, the bonded one is cut so as to have a longitudinal dimension L, a lateral dimension W and a thickness dimension C necessary for a filter. A filter unit A is formed by filling the cells 5 of this honeycomb-shape base material 1 with a granulated adsorbent 2 and bonding reticulated air permeable sheets 3 to both surfaces of the base material 1 through cobweb-like adhesive sheets 4 and integrating the whole by upper and lower frames 6, 7. Since the granulated adsorbent and the reticulated air permeable sheets are used, pressure loss is extremely low and, since the filter is reinforced by the frames, strength sufficiently withstanding practical use is provided.

Description

[Detailed Description of the Invention] Industrial Application Fields Demands for deodorization such as dust collection in general households and removal of odors from pets and toilets are becoming stronger year by year in proportion to improvements in the degree of sealing of buildings and the spread of air conditioning equipment. It is becoming.

The present invention relates to an air purifying filter for use in an air purifier based on such requirements.

BACKGROUND OF THE INVENTION Conventionally, this type of filter has been used by simply filling a flat or zigzag filter case with granular adsorbent. This method has drawbacks such as the filling rate changes due to transportation, vibration, etc., the generation of fine powder and dirt, and the flow path of the processing fluid changes, making it no longer able to achieve its initial purification performance. .

Furthermore, in order to compensate for these drawbacks, various filter processing methods have been proposed in recent years. That is, as shown in FIG. 11, granules of the adsorbent 32 are directly sprinkled on a thermoplastic resin nonwoven fabric 31 and bonded under heat to form a filter, or as shown in FIG. Select an adhesive such as a nonwoven fabric or three-dimensional mesh elastic sheet 33, and adsorbent 32.
They were also joining together.

Of these, the former has drawbacks such as a weak bonding force between the adsorbent 32 and the nonwoven fabric 31, and the components attached to the adsorbent deteriorate due to heat during heating. Also, the air pressure drop was high. In the latter case, since an adhesive is used, the solvent and solute may have a considerable effect on the adsorption capacity of the adsorbent, resulting in a decrease in the adsorption capacity and a tendency for uneven dispersion of the adsorbent.
This method had drawbacks such as an increase in pressure loss when the amount of adsorbent used increased.

Therefore, the present inventors have previously proposed an air purifying filter that solves the above-mentioned drawbacks (pending application). below,
Its configuration will be explained with reference to FIGS. 13 to 15.

This air purifying filter has a honeycomb-like base material 34 made of a thin aluminum plate or kraft paper hardened with phenolic resin, etc.
Put the adsorbent 36 into the cell 35 of No. 4, and put the nonwoven fabric 38 on both sides.
are joined together with a spider web-like adhesive sheet 39.

The air purifier used a combination of this air purification filter and a dust collection filter.

Problems to be Solved by the Invention However, in this air purifying filter, fine particles are usually included as the adsorbent 36 inside the filter, so the fiber basis weight of the nonwoven fabric 38 must be increased.
The disadvantage was that the pressure drop was high. In addition, the pressure drop is relatively low for laminar air flow, but there is a problem in that the pressure drop increases due to lateral flow and turbulent flow that occur in actual use as they collide with the walls of the honeycomb. .

The present invention is intended to solve the above problems, and the first object is to provide an air purifying filter that has low pressure loss and is resistant to falling and bending in order to realize an air purifier with low noise and large air volume. The second objective is to provide an air purifying filter that has a dust collection function in addition to the first objective.

Means for Solving the Problems In order to achieve the above-mentioned first object, the present invention includes a core material consisting of a plurality of cells containing an adsorbent such as granulated activated carbon, and a mesh-like air permeable structure on both sides of the core material. The sheets are pasted together and the whole is made up of a rigid frame.In order to achieve the second purpose, an adsorbent such as granulated activated carbon is placed in a core material consisting of a plurality of cells. A mesh-like breathable sheet is pasted on both sides of the core material, and a wire mesh is further provided in contact with the breathable sheet on the windward side, and a dust-collecting nonwoven fabric is further provided on the windward side, so that the mesh-like breathable sheet and the dust-collecting sheet are bonded together. It is made by fixing the non-woven fabric for use in a single piece.

Effect of the present invention With the above structure, the granulated adsorbent has a relatively uniform particle size and does not contain fine particles, so even if the breathable sheet covering both sides is in the form of a mesh, the adsorbent will not leak. Therefore, the pressure loss of the air purifying filter can be extremely reduced. There are fewer bonding points between the mesh-like breathable sheet and the cells than in the case of the nonwoven fabric of conventional filters. Therefore, by framing and integrating the cell with a hard material such as resin or metal, it is possible to prevent the adhesive points from coming off due to impact from dropping or bending, thereby preventing the adsorbent inside the cell from flying out.

Furthermore, although air purifiers usually use a deodorizing filter and a dust collection filter as a set, in the present invention, the two filters are integrated by heat sealing, resin, etc. with a rigid wire mesh between them. This prevents the adhesive point from coming off due to impact from dropping or bending, and from causing the adsorbent inside the cell to fly out. Further, when the dust collection filter is an electret filter, the wire mesh can also serve as an electrode for polarizing the electret filter.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 6. Honeycomb-shaped core material 1 consisting of multiple cells
The filter is made by bending thin sheets of aluminum or kraft paper, joining them with adhesive, then hardening them with phenolic resin, etc. to make them dimensionally thick (but not changing). (Fig. 4).In this example, kraft paper was used.Generally, the dimensions of cell 5 are indicated as summer dimensions, but 1
Dimensions and C dimensions greatly affect filter performance. In other words, the optimum dimensions are set based on the particle size of the adsorbent 2 such as activated carbon, the amount used, and the pressure drop. Generally, one dimension is 2 mm to 15 mm (12 mm was used in the example)
, it is easy to use a zero dimension of 3 mm to 20 mm (7 mm was used in the example).

The filter unit A is constructed by putting an adsorbent 2 into the cells 5 of such a honeycomb-shaped base material 1, bonding a mesh-like breathable sheet 3 on both sides with a web-like adhesive sheet 4, and forming an upper frame 6 and a lower frame. 7
It is unified by As the adsorbent 2, granulated ordinary activated carbon, activated carbon impregnated with a chemical effective against odor components, zeolite, silica, or alumina are used.

The particle size of the adsorbent 2 is determined based on the adsorption capacity, but generally cylindrical extruded products with a diameter of 2 mm to 4 mm and length of 2 mm to 7 mm, or spherical products with a diameter of 2 mm to 5 mm are used. . In the example, the diameter is 2 mm and the length is 2 mm.
Granulated charcoal of mm to 5 mm was used. One or more types of adsorbent 2 may be selected, but in the example, four types were selected: one for aldehydes, one for ammonia, one for sulfur, and one for hydrocarbons.

Next, the mesh-like breathable sheet 3 is made of polyester, acrylic,
A woven fabric made of thermoplastic resin such as PP or PE, the thickness of each loose thread is approximately 0.5 mm, and the pitch between the loose threads is approximately 1.
．． ．． Use a 5mm one. Here, an acrylic fiber that had been subjected to a conductive treatment in advance was used as the breathable sheet 3 in order to serve as an electrode during electrostatic precipitating. The conductivity may be at least one of the breathable sheets 3, and the conductivity is I
It was set to be less than KΩ/c111.

The adhesive sheet 4 for joining the core material 1 and the breathable sheet 3 is a nonwoven fabric made of solvent-free heat-welding resin (nylon, polyester, etc.) with a high aperture ratio, that is, spider web. Use a shaped adhesive sheet. In addition, the upper frame 6 and lower frame 7 are made of hard polypropylene or AB to prevent the filter unit A from bending due to falling.
The rigid frame is made of S resin or the like.

Regarding the processing procedure, first, only one side of the core material 1 and the breathable sheet 3 are joined together using a spider web-like adhesive sheet 4 by hot pressing or the like, and then the adsorbent 2 is uniformly sprinkled thereon. Next, the deodorizing filter B is completed by applying vibration and leveling with a brush, etc., placing the spider web-shaped adhesive sheet 4 on top, and then placing the breathable sheet 3 on top and heating with a hot press or the like. The hot pressing conditions here are 130°C x 2 to 3 seconds. Finally, the upper frame 6 and the lower frame 7 are fitted together at the periphery of the frame with the deodorizing filter B in between, so that the filter unit A is not bent.

Filter unit A for air purification obtained in this way
The size is 460mm x 308mm x 13mm thick (454mm x 302mm x about 7.5mm thick excluding the frame).
The amount of adsorbent is about 300g, which is used in an actual air purifier as shown in Figures 5 and 6.

In Figures 5 and 6, 10 is an air intake port, 11
1 is an air outlet, and 12 is a control section. Filter A for air purification is set using a jig 13 as shown in FIG. 14 is a pre-filter for removing large dust particles in the air; 15 is an electrostatic collection filter; 16 is a motor; 17 is a fan; and 18 is an air flow path. 19 is a discharge electrode of a positive electrode for generating high voltage for electrostatic precipitation;
The conductive portion on at least one side of the filter unit A functions as the counter electrode. 2o is the body of the air purifier.

The operation of the air purifier with the above configuration will be described. As the fan section 17 rotates, air is sucked in from the air suction ports 10 on both sides, and large dust particles are first removed by the pre-filter 14. Subsequently, fine dust and smoke are positively charged by the corona discharge of the discharge electrode 19, and are captured by the electrostatic precipitator filter 15. Thereafter, gas components such as odors are adsorbed by the adsorbent 2 of the filter unit A, and purified air exits from the air outlet 11.

Note that instead of the spider web-like adhesive sheet 4 in the above embodiment,
The breathable sheet 3 may be joined by directly applying hot melt resin to the core material 1 by spraying or by applying an adhesive within a range that does not affect the adsorbent 2.

A second embodiment of the present invention will be described below with reference to FIGS. 7 to 9.

The three-dimensional knitted fabric 21 is composed of a plurality of polygonal mesh cells.
This is the core material, and polygonal meshes 22 and 23 on the front and back sides knitted with twisted threads are connected in parallel with connecting threads 24 to form a breathable partition wall 25.
It is something that has. Here, the front and back polygonal mesh 22.2
3 is made of twisted polyester yarn, and the connecting yarn 24 is a single nylon yarn. The cell dimensions are generally expressed as 1' dimensions as shown in FIG. 9, and the 1' dimensions and C' dimensions greatly affect the performance of the filter. In other words, the optimum dimensions are set based on the particle size of the adsorbent 2 such as activated carbon, the amount used, and the pressure drop. Generally 1' dimension is 2mm
~15 mm (12 mm was used in the example), and a C' dimension of 3 mm ~ 20 mm (7 mm was used in the example) is easy to use.

The filter unit A' is made by putting the adsorbent 2 into the cells 26 of such a three-dimensional knitted fabric 21, joining a breathable sheet 3 on both sides with a web-shaped adhesive sheet 4, and forming an upper frame 27 and a lower frame 28.
It is unified by As in Example 1, as the adsorbent 2, there were four types of adsorbent for aldehydes, for ammonia, for sulfur, and for hydrocarbons, each having a diameter of 2 mm and a length of 2 mm.
Granulated coal of 5 mm was used.

Also, the same breathable sheet 3 and adhesive sheet 4 as in Example 1 were used. The upper frame 27 and the lower frame 28 are also made of hard polypropylene, ABS resin, or the like to prevent them from being bent and unbonded due to a fall or the like.

The processing procedure is as follows: First, the three-dimensional knitted fabric 21 and the breathable sheet 3 are joined together on one side only by hot pressing or the like using a nest-like adhesive sheet 4, and then the adsorbent 2 is uniformly sprinkled over the top. The deodorizing filter B' is completed by smoothing it with a brush, etc., placing the spider web-shaped adhesive sheet 4 on top of it, and then placing the breathable sheet 3 on top and heating it with a hot press, etc. Hot pressing conditions Here, the temperature is 135° C.×4 to 5c11.Finally, the upper frame 27 and the lower frame 28 are fitted together at the periphery of the frame with the filter B′ in between,
The filter unit A' is integrated so that it does not bend.

Filter unit A for air purification obtained in this way
” is the same as the first example, 460 mm x 308
mm x thickness 13mm (454mm excluding frame)
x 302 mm x thickness of about 7.5 mm), and the amount of adsorbent is about 300 g, which is used in an actual air purifier as shown in Figs. 5 and 6.

Next, a third embodiment of the present invention will be described with reference to FIG.

Here, first, a deodorizing filter C was made using the same materials and the same method as the deodorizing filter B of the first embodiment. Next, on the windward side of this deodorizing filter C, a 14 mesh 5US430
An electrostatic dust collection filter 30 made of polypropylene is placed across a wire mesh 29 made of
A and the outer periphery of the deodorizing filter C were heated at 130° C. to 150° C. for 3 seconds to 7 seconds to fuse together to obtain a filter unit D. Here, the wire mesh 20 is used to supplement the strength of the deodorizing filter C, but since it also functions as a counter electrode for electric dust collection, the breathable sheet 3 does not need to be electrically conductive.

Filter unit D for air purification obtained in this way
Filter C is 186mm x 123mm x thickness approx.
5 mm, the amount of adsorbent 6 is about 50 g, and is used in an actual air purifier as shown in FIGS. 5 and 6. In this embodiment, a filter unit D is set on a jig 13 and used.

Next, the filters of the first to third Examples (Example 1.2.3) and the unreinforced deodorizing filter B (Comparative Example 1),
B' (Comparative Example 2), C (Comparative Example 3), and Figures 10-
The pressure loss and filter strength were compared with a filter using a honeycomb core using crushed coal and kraft paper (Comparative Example 4) shown in Fig. 12.

In the filter of Comparative Example 4, the dimensions of the kraft paper cells are 12 mm and the thickness of 7 mm, which are the same as in Example 1.3, and the adsorbent 36 is 6 me sh to 12 me sh (approximately 4 m
m to 2 mm), for aldehydes, for ammonia,
300g of 4 types of crushed coal for sulfur compounds and hydrocarbons
was used. In addition, the nonwoven fabric 38 is made of Bossester, acrylic,
A fibrous nonwoven fabric made of thermoplastic resin such as PP and PE and having a basis weight of 30 g/'d was used. The spider web-like adhesive sheet 39 was also the same as in each example, and the dimensions of the filter were 454 mm x 302 mm.

To evaluate the pressure loss, use the filter alone at a flow rate of 1. m/s
Measurements were made in laminar flow. In addition, filter strength indicates the number of filters that are unattached or broken out of 10 filters when the filters are dropped from a height of 70 cm onto the floor three times with their two corners facing down. The results are shown in Table 1.

As is clear from the results in Table 1, all of the filters of the examples of the present invention have extremely lower pressure loss than the conventional filter of Comparative Example 4, and have superior filter strength. It is.

Furthermore, by applying antibacterial and antifungal treatment to each breathable sheet, it is possible to suppress the growth of germs, bacteria, mold, and the like.

Effects of the Invention As is clear from the above examples, since the present invention uses a granulated adsorbent and a mesh-like breathable sheet,
It has an extremely low pressure drop, and because the filter is reinforced with a frame and the dust collection nonwoven fabric and deodorizing filter are integrated with a wire mesh in between, it has an extremely low pressure drop and is strong enough to withstand actual use. Filters can be provided.

Moreover, the air purifying filter according to the present invention enables an air purifier with low noise and large air volume.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a filter according to an embodiment of the present invention, and FIG.
3 is a partially enlarged sectional view of FIG. 1, FIG. 4 is a perspective view of the core material, and FIG. 5 is a plan view thereof. FIG. 6 is a perspective view and a sectional view of an air purifier in which the air purifying filter of the present invention is used, FIG. 7 is a longitudinal sectional view of an air purifying filter that is another embodiment of the present invention, and FIG. is a partially enlarged sectional view, Figure 9 is a perspective view of the three-dimensional knitting, and Figure 1 is a perspective view of the three-dimensional knitting.
Figure 0 is a vertical cross-sectional view of an air purifying filter that is yet another embodiment of the present invention, Figures 11 and 12 are cross-sectional views showing the configuration of conventional filters, and Figure 13 is a cross-sectional view of a filter that has been proposed so far. A sectional view of the filter, FIG. 14 is an enlarged sectional view at section E in FIG. 13, and FIG. 15 is a perspective view of the core material in FIG. 13. 2...Adsorbent, 3...Breathable sheet,
6... Upper frame, 7... Lower frame, 29...
... Wire mesh, 30 ... Electrostatic precipitator filter. Agent's name: Patent attorney Haruaki Koebi and 2 others Fig. Fig. Hibiki Kima ** ellK ball cup @H ~ Tsu N Ku wo glaze tip 1' 2 Do 0 Ko Fig. 11 Fig. 12 or 4

Claims (2)

[Claims] (1) An air purifying filter in which an adsorbent such as granulated activated carbon is placed in a core material consisting of multiple cells, a mesh-like breathable sheet is attached to both sides of the core material, and the whole is integrated with a rigid frame. . (2) Put an adsorbent such as granulated activated carbon into a core material consisting of multiple cells, attach a mesh-like breathable sheet to both sides of the core material, and then attach a wire mesh in contact with the breathable sheet on the windward side. Further, a dust collecting non-woven fabric is provided on the windward side thereof, and the air purifying filter is integrated by fixing the mesh-like breathable sheet and the dust collecting non-woven fabric.