JP3691160B2 - Process for processing air filter medium and filter pack for air filter manufactured in this process - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to air filters used for air conditioning equipment for buildings air conditioning, general industry, medical equipment, etc., and clean rooms, etc., and particularly requires a thin and low pressure loss that can be applied to an individual dispersion type air conditioner. The present invention relates to a method for processing an air filter medium and a filter pack for an air filter manufactured by the processing.
[0002]
[Prior art]
A conventional processing method for this type of filter medium will be described based on the apparatus configuration shown in FIG.
First, the band-shaped filter medium 10 is sent to the creasing device 11 and creasing is performed at intervals of the folding width. Then, after the creasing is performed, the hot melt resin application device 12 applies the hot melt resin of the linear spacers to both surfaces of the filter medium 10. And after apply | coating hot-melt resin, the filter medium is folded in the zigzag shape with the filter medium folding apparatus 13, and the filter pack is manufactured.
Moreover, generally the glass fiber filter medium is used as a filter medium processed with the said conventional filter medium processing method.
[0003]
[Problems to be solved by the invention]
However, in recent years, the air conditioning method has changed from the centralized method to the individual dispersion method, and the filter used for this individual dispersion method has been required to be particularly thin and have a low pressure loss. For example, organic fibers such as polypropylene are used. An electret filter in which an electrostatic force is applied to a filter medium has attracted attention.
This organic fiber filter has the characteristic that the repulsive force is extremely strong as compared with the glass fiber filter.
Therefore, when this organic fiber filter medium is processed by the conventional processing method, the resulting filter pack is as shown in FIG.
That is, the filter pack has a curved surface of the filter medium, the gap A between the folded walls is not constant, and has a contact portion B where adjacent folded walls come into contact with each other.
Thus, when the gap A between the folding walls of the filter medium is non-uniform and has the contact portion B, there is a problem that the air flow resistance increases and the pressure loss becomes high.
Accordingly, an object of the present invention is to provide a method for processing an air filter medium in which a folded wall does not bend even if the organic fiber filter medium has a strong repulsive force, and an air filter filter pack manufactured by this process.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the air filter medium processing method according to the present invention includes a linear spacer on the surface of a thermoplastic resin filter medium, and the filter medium is folded into a zigzag shape to a certain width. In the processing method of the filter medium for air filter at the time of manufacturing, the filter medium is once folded into a certain width in the pre-process of the step of attaching the linear spacer, and the folded section of the filter medium is configured in the folded state. The heat treatment is performed at a temperature lower than the melting point of the thermoplastic resin and higher than the heat distortion temperature .
[0005]
According to a second aspect of the present invention, there is provided a method of processing a filter medium for an air filter according to the present invention, wherein a linear spacer is provided on the surface of a thermoplastic resin filter medium, and the filter medium is folded in a zigzag shape to a certain width to produce a filter pack. In the processing method of the filter medium for air filter, the process of folding the filter medium to a certain width and compressing the folded filter medium so that the folded walls of the filter medium are in close contact with each other. A step of heat treatment at a temperature lower than the melting point of the thermoplastic resin constituting the resin and at a temperature equal to or higher than the heat distortion temperature, a step of extending the filter medium folded in the step and attaching a linear spacer to the surface of the filter medium, and a linear spacer in the step The method further comprises the step of folding the filter medium provided with the filter material again.
[0006]
According to a third aspect of the present invention, there is provided a method for processing an air filter medium according to the first or second aspect of the present invention. It is characterized by carrying out by placing a filter medium between two heating plates so as to abut against each other.
[0007]
According to a fourth aspect of the present invention, the filter pack for an air filter according to the present invention is a filter pack for an air filter in which spacers are linearly attached to the surface of a filter medium made of thermoplastic resin, and the filter medium is folded in a zigzag shape to a certain width . Before attaching the spacer in a linear shape, at least the bent portion of the filter medium is heat-treated at a temperature lower than the melting point of the thermoplastic resin constituting the filter medium and above the heat distortion temperature . .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The filter medium used in the present invention is an organic fiber nonwoven fabric or a polymer film made of thermoplastic resin. The organic fiber nonwoven fabric can be used as an electret filter by imparting electrostatic force. Moreover, since both the organic fiber nonwoven fabric and the polymer film are extremely thin and do not have self-shape retention, an organic fiber nonwoven fabric made of a thermoplastic resin can be laminated on at least one surface for reinforcement.
The linear spacer is made of a polyolefin-based or polyamide-based hot-melt adhesive (hot-melt resin) alone or using a core material coated with these hot-melt adhesives, and the string, thread, ribbon The tape-shaped one is formed continuously or discontinuously.
And as an apparatus for folding such a filter medium in a zigzag shape, the air filter filter medium processing apparatus of the present invention includes a folding section for folding the filter medium and a compression section for compressing the folded filter medium so that the folded wall is in close contact with the filter medium. And a heating part for heating the folded part of the folded filter medium. And by using this apparatus and heat-treating the filter medium in a folded state, the surface of the filter medium can be folded sharply without being curved regardless of the strong repulsive force of the filter medium. Therefore, the gap between the folded walls does not become non-uniform and does not have a contact portion.
[0009]
In the present invention, the heat treatment at this time is performed by placing the filter medium between the two heating plates so that the bent portion of the filter medium comes into contact with the heating plate, thereby reducing the influence of heating to other than the bent portion. can do. Accordingly, it is possible to prevent the collection efficiency from being lowered by heating the electret filter medium.
In addition, the present invention does not affect the function of the linear spacer without affecting the function of the linear spacer by performing this heat treatment before the linear spacer attaching process. There is no inconvenience that predetermined folding cannot be performed by the spacer.
Further, according to the present invention, when the heat treatment is performed, the filter medium can be folded more sharply by compressing the folded filter media so that the folded walls are in close contact with each other. In the filter pack for an air filter of the present invention processed as described above, the folded portion of the filter medium is heat-treated, and the filter medium surface is sharply folded without being curved.
[0010]
【Example】
First, the filter medium used in the present embodiment will be described.
The filter medium used in the present example is a laminate obtained by laminating a nonwoven fabric obtained by mixing polyclar fiber, vinylon, and polyester as a reinforcing material with a modified EVA resin binder on a polypropylene nonwoven fabric subjected to electret treatment.
Embodiments of a method for processing an air filter medium according to the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram of an apparatus for performing the machining method. As shown in the figure, a folding processing device 1 for heat-treating a bent portion, a hot-melt resin coating device 2 for coating a hot-melt resin as a linear spacer, and a filter medium folding device 3 for forming a filter pack, have. The filter medium 4 is guided to each device by a plurality of rolls 5a to 5k. The folding processing device 1 includes a folding unit 1a that folds the filter medium 4 into a zigzag shape, a compression unit 1b that compresses the folded filter medium 4 so that the folded wall is in close contact, and a heating unit that heats the folding unit of the folded filter medium 4 1c. Here, the heating unit 1c is composed of two opposing upper and lower heating plates, and the filter medium 4 is disposed so that the bent portion abuts on the heating plate. Moreover, the compression part 1b is comprised from the partition board provided in the exit side of this heating part 1c. The hot melt resin coating apparatus 2 includes a tank 2a in which the hot melt resin is heated and melted, and nozzles 2b and 2c that discharge the molten hot melt resin in the tank 2a in appropriate amounts. A plurality of hot melt resins are applied to the surface of the filter medium 4 with a predetermined interval.
[0011]
Next, the processing method of the filter medium when using the above apparatus will be described.
First, the belt-shaped filter medium 4 is sent to the folding processing apparatus 1 by rolls 5a and 5b. The filter medium 4 sent to the folding processing device 1 is folded into a constant width in a zigzag manner by the folding portion 1a. The filter medium 4 folded by the folding section 1a is continuously fed in a zigzag state between the heating sections 1c composed of a pair of upper and lower heating plates. Therefore, the folded filter medium 4 moves between the heating parts 1c as it is pushed, and is sent to the outlet side of the heating part 1c. Since the zigzag filter medium 4 sent to the outlet side of the heating unit 1c is blocked by the compression unit 1b made of a partition plate or a compression rod, the filter medium 4 is compressed so that the folded walls of the filter medium 4 are in close contact with each other. The At this time, the heating unit 1c is heated at a temperature of about 60 ° C to 80 ° C. Thus, since the filter medium 4 heats a bending part in a compression state, it produces a thermal deformation in a bending part.
In this way, the filter medium 4 bent by the folding processing apparatus 1 is dammed up by a certain amount by the partition plate and is heated, and then is removed again by removing the partition plate and opening the rolls 5c to 5g. The hot melt resin is applied by the hot melt resin coating apparatus 2 via the above. First, hot melt resin is applied to one surface of the filter medium 4 from the nozzle 2b in a state where a predetermined tension is applied by the rolls 5c and 5d. Thereafter, the upper and lower surfaces of the filter medium 4 are replaced by the rolls 5c and 5d, and hot melt resin is applied to the other surface of the filter medium 4 from the nozzle 2c in a state where a predetermined tension is applied by the rolls 5f and 5g. Thereafter, the filter medium 4 is finally folded by the filter medium folding device 3 through the rolls 5h, 5i, and 5j.
In this example, since a nonwoven fabric obtained by laminating a non-woven fabric obtained by mixing polyclar fiber, vinylon, and polyester with a modified EVA resin binder to a reinforcing material as a reinforcing material was used as a filter material, the heating temperature was 60 ° C to 80 ° C. However, the present invention is not limited to this, and the heating temperature may be lower than the melting point of the thermoplastic resin constituting the filter medium and not less than the heat distortion temperature.
Further, the method of applying the hot melt resin is not limited to the present embodiment, and any method can be used as long as it functions as a linear spacer.
In this embodiment, folding is performed for the first time in the folding processing apparatus, but it is also possible to facilitate folding by providing a line before being guided to the folding processing apparatus in advance.
[0012]
【The invention's effect】
As is apparent from the above description, according to the present invention, a method for processing an air filter medium in which a folded wall is not curved even with an organic fiber filter medium having a strong repulsive force, and an air filter medium processing apparatus used for this processing And the filter pack for air filters manufactured by this process can be provided.
[Brief description of the drawings]
1 is an apparatus configuration diagram according to an embodiment of the present invention. FIG. 2 is an apparatus configuration diagram according to a conventional example. FIG. 3 is an enlarged side view of a main part of a filter pack according to a conventional example.
DESCRIPTION OF SYMBOLS 1 Folding processing apparatus 1a Folding part 1b Compression part 1c Heating part 2 Hot melt resin coating apparatus 3 Filter medium folding apparatus 4 Filter medium

Claims (4)

In the method of processing a filter medium for air filter when a filter pack is manufactured by attaching a linear spacer on the surface of a thermoplastic resin filter medium and folding the filter medium in a zigzag shape to a certain width, the step of attaching the linear spacer In the preceding step, the filter medium is once folded into a certain width, and in this folded state, the folded portion of the filter medium is heat-treated at a temperature lower than the melting point of the thermoplastic resin constituting the filter medium and above the heat distortion temperature. The processing method of the filter medium for air filters characterized by these. In a method for processing a filter medium for an air filter when a filter pack is manufactured by attaching a linear spacer on the surface of a thermoplastic resin filter medium and folding the filter medium in a zigzag shape to a certain width, the filter medium is made a certain width. The folding process and the folded filter medium are compressed so that the folded walls of the filter medium are in close contact with each other, and in this compressed state, the folded portion of the filter medium is heated at a temperature lower than the melting point of the thermoplastic resin constituting the filter medium and above the heat distortion temperature. An air filter comprising: a treatment step; a step of extending the filter medium folded in the step to attach a linear spacer to the surface of the filter medium; and a step of refolding the filter medium provided with the linear spacer in the step Processing method of filter media.   The air filter according to claim 1 or 2, wherein the heat treatment of the filter medium is performed by disposing a filter medium between two heating plates so that a bent portion of the filter medium contacts the heating plate. Processing method of filter media. In a filter pack for an air filter in which a spacer is linearly attached to the surface of the thermoplastic resin filter medium, and the filter medium is folded in a zigzag shape to a certain width, before attaching the spacer in a linear form, at least the filter medium A filter pack for an air filter , wherein the bent portion is heat-treated at a temperature lower than the melting point of the thermoplastic resin constituting the filter medium and above the heat distortion temperature .

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