JP7393198B2 - Filter pack and air filter - Google Patents

Description

The present invention relates to a filter pack including a pleated filter medium and an air filter.

BACKGROUND ART As an air filter that collects dust floating in the air, one that includes a filter pack and a frame body in which the filter pack is housed is used. The filter pack includes, for example, a filter medium that is pleated and folded into a zigzag shape to ensure a collection area.

When the amount of dust collected and held by the filter medium increases, it becomes difficult for air to flow through the filter medium, and pressure loss tends to increase. As a conventional air filter, one is known that is configured so that the frame body can be reused while replacing the filter pack that has reached the end of its service life when the amount of dust retained reaches a predetermined amount (for example, see Patent Document 1). ).

In the air filter of Patent Document 1, the filter frame is provided with a flange extending toward the ventilation surface only on the downstream side of the ventilation passage, and the filter pack is configured to be removable from the upstream side of the filter frame.

Japanese Patent Application Publication No. 2011-83713

Even if the above air filter is configured so that the filter pack can be replaced, if it is used in a place where a large amount of dust is floating, the amount of dust retained will quickly reach the specified amount, and the filter pack will have to be replaced more frequently. Therefore, it is not economical. Here, if the retained dust is removed from the filter pack removed from the frame and the filter pack can be stored in the frame and used again, there is no need to replace the filter pack, and the filter pack can be used continuously. However, it is not easy to remove dust from a filter medium that is pleated and folded into a zigzag shape, and requires the use of a dedicated device, for example.

An object of the present invention is to easily remove particulates retained on the filter material in a filter pack including a pleated filter material.

One aspect of the present invention is a filter pack, comprising:
A pleated filter material that collects fine particles in the gas,
a surrounding member that circumferentially surrounds the filter medium so that the folds of the pleats are exposed;
The surrounding member is
two first fixing parts fixed to the filter medium so as to sandwich the filter medium from both sides in the extending direction of the fold;
two second fixing parts fixed to the filter medium so as to sandwich the filter medium from both sides in a direction perpendicular to the direction in which the folds extend and the direction of airflow passing through the filter medium;
When the filter pack is compressed or expanded in the orthogonal direction so that the interval between adjacent pleats changes, the amount of displacement of the second fixing part along the orthogonal direction is equal to the amount of displacement of the second fixing part in the orthogonal direction. The larger the part of the second fixing part is, the further away from the
The length of the filter pack along the orthogonal direction is such that the amount of displacement of the second fixing part is greater at the first position in the direction parallel to the extending direction of the fold than at the first position. longer than the smaller second position;
Each of the fixing parts has a plate-shaped structural material made of plastic,
The structural material is
two sheets facing each other,
a plurality of ribs extending in one direction and spaced apart from each other, each of the ribs being arranged in parallel to each other to form a plurality of spaces surrounded by the ribs and the sheet and extending in one direction; has a plurality of ribs connecting the two sheets,
A bending strength of the second fixing portion in an out-of-plane direction is 3.0 N/mm ² or less .

Each of the fixing parts has a plate-like structural material,
The structural material is
sheets facing each other,
It is preferable to have a plurality of ribs extending in one direction and arranged at intervals, each connecting the sheets.

In the second fixing part, it is preferable that the rib extends in the direction in which the fold line extends.

In the first fixing part, it is preferable that the rib extends in the orthogonal direction.

Preferably, the enclosing member further includes a covering member that covers the structural member.

It is preferable that the filter medium has a pair of protrusions provided on adjacent pleated portions of the filter medium so as to come into contact with each other when the filter medium is folded.

It is preferable that the filter medium is not provided with a reinforcing material extending over the tops of the pleats so as to extend in the orthogonal direction.

Another aspect of the present invention is an air filter, comprising:
The filter pack;
a frame body in which the filter pack is housed and comes into contact with the filter pack;
The frame body has four frame side parts that extend linearly and are arranged to face each of the first fixing part and the second fixing part,
The second fixing part is characterized in that it deforms along the shape of the frame side part in response to the force of the filter medium that tends to widen the interval between adjacent pleats.

According to the above aspect, in a filter pack including a pleated filter medium, it is possible to easily remove particulates retained on the filter medium.

FIG. 1 is an external perspective view showing a filter pack according to an example of the present embodiment. (a) and (b) are diagrams explaining the operation of the filter pack. It is a figure which shows the structural material of a fixed part. FIG. 3 is a diagram showing a cross section of the air filter taken along a plane extending in the direction of air flow and the direction in which folds extend. It is a figure showing an example of a frame.

The filter pack of this embodiment will be explained below.
FIG. 1 is an external perspective view showing a filter pack 1 according to an example of the present embodiment.
The filter pack 1 includes a filter medium 3 and a surrounding member 5.

The filter medium 3 is a member that collects fine particles in the gas. The filter medium 3 is used, for example, to remove dust with a particle size of 0.7 μm or less and a concentration of 0.5 mg/ ^m3 or less, and has a collection efficiency of 65% or more by counting method, a pressure loss of 79 to 493 Pa, and dust retention. Those with a dust retention capacity of 200 to 800 g/m ² are used. In the counting method, measurement is performed by passing through air containing particles of atmospheric dust, polyalphaolefin (PAO), or silica with a particle size of 0.3 μm. Dust holding capacity is the amount of dust that the filter captures before reaching a predetermined final pressure drop. Moreover, the filter medium 3 may be, for example, a filter medium for a HEPA filter, a filter medium for a ULPA filter, or a filter medium for a gas removal filter.

The filter medium 3 is, for example, a fibrous body made of glass fiber, organic fiber, or a mixed fiber of these fibers, and is, for example, a nonwoven fabric or felt. The filter medium 3 made of glass fiber is produced, for example, by paper-making using a wet method or a dry method. The filter medium 3 made of organic fibers is produced by, for example, a spunbond method, a melt blow method, a thermal bond method, a chemical bond method, or the like. Further, the filter medium 3 may be, for example, a layered structure of a plurality of nonwoven fabrics having different collection efficiencies.

As shown in the figure, the filter medium 3 is pleated so that mountain folds and valley folds are alternately repeated. Pleating is performed using a reciprocating or rotary folding machine. The filter medium 3 is pleated and has a plurality of folds 3a.

The surrounding member 5 is a member that circumferentially surrounds the filter medium 3 so that the folds 3a of the pleats are exposed. The filter medium 3, which is pleated and folded into a zigzag shape, has an approximately rectangular parallelepiped outer shape. The folds 3a of the pleats are arranged so as to be exposed on two opposing faces of the six faces of the rectangular parallelepiped. The surrounding member 5 circumferentially surrounds the filter medium 3 by being arranged to face the other four surfaces of the rectangular parallelepiped.

The surrounding member 5 has two first fixing parts 5a, b and two second fixing parts 5c, 5d.

The first fixing parts 5a and 5b are parts that are fixed to the filter medium 3 so as to sandwich the filter medium 3 from both sides in the extending direction of the fold line 3a. In the following description, the extending direction of the fold line 3a means the extending direction of the fold line 3a extending linearly among the plurality of fold lines 3a (Z direction in FIG. 1). The length of the first fixed portions 5a, 5b in the Y direction is approximately equal to the distance between two surfaces facing in the Y direction among the inner wall surfaces of the frame 11, which will be described later.

The second fixing portions 5c and 5d are arranged in a direction (Y direction in FIG. 1) perpendicular to the extending direction of the fold line 3a and the direction of airflow passing through the filter medium 3 (X direction in FIG. 1; hereinafter also referred to as the airflow direction). This is a portion that is fixed to the filter medium 3 so as to sandwich the filter medium 3 from both sides in the Y direction (hereinafter referred to as the Y direction).

The second fixing parts 5c and 5d are second fixing parts along the Y direction when the filter pack 1 is compressed or expanded in the Y direction so that the interval between adjacent pleats (hereinafter simply referred to as pleat interval) changes. The portions 5c and 5d have a characteristic that the displacement amount is larger as the portions of the second fixing portions 5c and 5d are farther from the first fixing portions 5a and 5b, that is, they have more flexibility. The second fixing portions 5c and 5d have flexibility, so that they can bend in the Y direction so as to bulge or dent in response to a force in the Y direction. The length of the second fixed portions 5c and 5d extending linearly in the X direction is approximately equal to the distance between two inner wall surfaces of the frame 11 that face each other in the X direction.

The length of the filter pack 1 along the Y direction is such that at a first position in a direction parallel to the direction in which the fold line 3a extends, the amount of displacement of the second fixing parts 5c and 5d is smaller than at the first position. It is longer than position 2. In other words, as shown in FIG. 1, the length of the filter pack 1 along the Y direction increases as the distance from the first fixing parts 5a, 5b increases in the direction parallel to the extending direction of the fold line 3a. long. Specifically, in the filter pack 1, the second fixing parts 5c and 5d are deformed by receiving at least the force of the filter medium 3 that tends to widen the pleat interval, so that the length L1 at the first position is , is longer than the length L2 at the second position. In the filter pack 1, the filter medium 3 is folded into a zigzag shape and is further surrounded by the enclosing member 5 in a press-contact state in the Y direction, so that a force in the Y direction is applied to the second fixing parts 5c and 5d. to act. In the filter pack 1, the length L1 of the filter pack 1 is longer than the length L2 due to forces generated within the filter pack 1, including the force of the filter medium 3.

Since the second fixing parts 5c and 5d have flexibility in this way, the filter pack 1 of this embodiment can change the length along the Y direction, as shown in FIG. . FIG. 2 is a diagram illustrating the operation of the filter pack 1. In FIG. 2, illustration of the fold line 3a of the filter medium 3 is omitted. Since the second fixing parts 5c and 5d have flexibility, when the filter pack 1 receives a force to be compressed along the Y direction, the filter pack 1 is compressed in the Y direction as shown in FIG. It can be compressed in the direction and become concave inward. Furthermore, when the above-described force that compresses the filter pack 1 is released from the filter pack 1 having a shape concave inward in this way, the above-mentioned force of the filter medium 3 that tends to widen the pleat interval is applied to the second fixing portion 5c, 5d, it returns to the shape that expands in the Y direction and bulges outward, as shown in FIG. 2(a). By quickly repeating applying and releasing such a force to compress the filter pack 1 in the Y direction, for example, 2 to 10 times, at least a portion of the dust retained in the filter medium 3 can be easily removed. removed.

The bending strength of the second fixed portions 5c and 5d in the out-of-plane direction of the plane extending in the extending direction of the fold line 3a and the airflow direction is preferably 3.0 N/mm ² or less, and 1.5 N/mm ² It is more preferable that it is below. When the bending strength is in such a range, the filter material 3 is easily bent by the force of the filter medium 3 which tends to widen the pleat interval or by the force which compresses the filter pack 1 in the Y direction. Note that the lower limit of the bending strength in the out-of-plane direction of the second fixing portions 5c and 5d is, for example, 0.5 N/mm ² .

As shown in FIG. 1, the fixing parts 5a, 5b, 5c, and 5d are preferably connected to each other so as to be continuous in a circumferential manner.

It is preferable that each of the fixing parts 5a to 5d has a plate-like structural material. The plate-shaped structural member is arranged to face the four surfaces of the substantially rectangular parallelepiped filter medium 3. It is preferable that the structural material and the filter medium 3 are bonded using an acrylic adhesive, a rubber adhesive, or the like so that they do not separate during ventilation.

A preferred form of the structural material is the form shown in FIG. 3. FIG. 3 is a diagram showing the structural member 6. As shown in FIG. The structural member 6 shown in FIG. 3 includes two sheets 6a and a plurality of ribs 6b. The sheets 6a are arranged opposite to each other, ie parallel to each other. The ribs 6b each extend in one direction (vertical direction in FIG. 3) and are spaced apart from each other. The ribs 6b connect the sheets 6a, 6a, respectively. Therefore, the structural member 6 has a hollow structure in which a plurality of spaces extending in one direction are arranged in parallel to each other. The thickness of the sheet 6a and the rib 6b is, for example, 0.5 to 4 mm, respectively. The thicknesses of the sheet 6a and the ribs 6b are, for example, equal.

As a preferable material for the structural member 6 shown in FIG. 3, plastics such as polypropylene resins can be mentioned because the flexibility of the second fixing parts 5c and 5d can be easily obtained. Note that the structural member 6 shown in FIG. 3 made of plastic material is also called plastic cardboard.

In the first fixing portions 5a, 5b, the ribs 6b preferably extend in the Y direction. As a result, the first fixing parts 5a and 5b are prevented from deforming in a swollen manner in response to a force that compresses the filter pack 1 in the Y direction, compared to a case where the ribs 6b are arranged to extend in the airflow direction. Ru.

It is preferable that the structural members 6 arranged in each of the fixing parts 5a to 5d are connected to each other with an adhesive and continuous in a circumferential manner.

The structural material is not limited to the form shown in FIG. 3, and may be a plate material, for example. Preferred materials for the plate include metals such as stainless steel and aluminum, and plastics.

It is preferable that the surrounding member 5 further includes a covering member 7 that covers the structural member 6, as shown in FIG. FIG. 4 is a diagram showing a cross section of the air filter 10 along a plane extending in the airflow direction and the direction in which the folds extend (a plane perpendicular to the Y direction). In FIG. 4, the filter pack 1 is shown housed in a frame 11. As shown in FIG. Since the enclosing member 5 has the covering member 7, when the filter pack 1 is housed in the frame 11, a gap is suppressed from forming between the filter pack 1 and the frame 11, thereby preventing leakage. can. It is preferable that the covering member 7 is adhered to the structural material 6 using an acrylic adhesive, a rubber adhesive, or the like.

Preferred materials for the covering member 7 include rubber, fibrous bodies, foams, and sponges, and among them, rubber is preferred.

Examples of preferable rubbers include urethane rubbers such as polyether-based and polyester-based urethane rubbers, chloroprene rubber, and ethylene propylene diene rubber (EPDM). The density of the rubber is preferably 10 to 100 kg/m ³ , more preferably 20 to 50 kg/m ³ . According to one embodiment, the rubber is preferably a foamed rubber having a plurality of independent cells or a plurality of cells, some of which are continuous.

An example of a preferable fibrous body is a nonwoven fabric. Examples of nonwoven fabrics include those made from organic fibers such as polyester, polyamide, polypropylene, and polyethylene by a chemical bonding method, thermal bonding method, or spunbond method, and those made from glass fibers by a dry process. The glass fibers are preferably short fibers having an average fiber diameter of 1 μm or less, for example.

A preferred form of the covering member 7 is a sheet shape. The thickness of the sheet-like covering member 7 is preferably 1 to 10 mm.

It is preferable that the covering member 7 covers the entire surface of the enclosing member 5 facing the frame 11.
Further, it is preferable that the covering member 7 is bent inward in a direction orthogonal to the airflow direction at least at the downstream end of both ends of the filter pack 1 in the airflow direction. Thereby, it is possible to suppress the formation of a gap between the flange 11e provided at the downstream end of the frame 11 in the airflow direction and the filter pack 1. The length of the portion of the enclosing member 5 bent in the direction perpendicular to the airflow direction is, for example, within 30 mm at each of both ends in the airflow direction. The filter pack 1 in the example shown in FIG. 4 is bent inward in a direction perpendicular to the airflow direction at both ends in the airflow direction.

It is preferable that the filter medium 3 has a pair of protrusions (not shown) provided in adjacent pleated portions of the filter medium 3 so as to come into contact with each other when the filter medium 3 is folded. As the protrusions abut against each other, the pleat spacing is kept uniform. The protrusions are provided on the filter medium 3 by, for example, embossing. For example, the protrusions are formed so that a plurality of protrusions are arranged in a row in a direction perpendicular to the direction in which the fold line 3a extends, and a plurality of rows of protrusions are arranged at intervals in the direction in which the fold line 3a extends. has been done. Protrusions are well known, and the arrangement, height, shape, etc. of the protrusions are determined, for example, as in the "embossed protrusion" described in International Publication No. 2013/031229.

When the filter medium 3 having such protrusions is folded into a zigzag shape and a compression force is applied in the Y direction, the flat part of the filter medium 3 surrounding the protrusions bends, resulting in further Y It is easily compressed in the direction. That is, when the filter medium 3 is folded, it is likely to be compressed so that the pleat interval when the protrusions abut each other becomes even narrower. Therefore, it is possible to ensure a large difference in the amount of displacement of the second fixing parts 5c and 5d between when the filter pack 1 is compressed and when it is expanded, and the dust retained on the filter medium 3 can be efficiently removed.

On the other hand, the filter pack 1 may have a plurality of spacers (not shown) provided on the filter medium 3 in order to maintain uniform pleat intervals instead of the filter medium 3 having a plurality of protrusions. .
The spacer is a linear member extending on both sides of the fold line 3a in a direction perpendicular to the fold line 3a on the surface of the filter medium 3 facing the outside of the pleats. The spacer is provided by applying a hot melt adhesive to the surface of the filter medium 3 and solidifying it.

It is preferable that the filter medium 3 is not provided with a reinforcing material that spans the tops of the pleats so as to extend in the Y direction. The reinforcing material is made using, for example, a hot melt adhesive. When such a reinforcing material is provided in the filter medium 3, it tends to become difficult for the filter pack 1 to compress or expand in the Y direction.

The ratio (aspect ratio) of the length in the X direction (vertical length) to the length in the Y direction (horizontal length) of the filter pack 1 is set such that the ratio (vertical length: horizontal length) of the filter pack 1 increases the removal efficiency of dust retained in the filter medium 3. is determined, for example, in the range of 3:1 to 1:3.

The dimensions of the filter pack 1 are not particularly limited, but the length in the X direction (vertical length) is, for example, 300 to 800 mm, the length in the Y direction (horizontal length) is, for example, 300 to 800 mm, and the length in the Z direction ( The depth) is, for example, 50 to 300 mm.

The number of pleats included in the filter pack 1 is, for example, 50 to 200. The pleat interval is, for example, 5 to 10 mm. The folding width of the filter medium 3 (the distance between adjacent folds 3a) is 40 to 260 mm.

Next, the air filter of this embodiment will be explained.
The air filter includes a filter pack 1 and a frame 11, as shown in FIG.

The filter pack 1 is configured similarly to the filter pack 1 described above.

The frame body 11 is a member in which the filter pack 1 is housed. The filter pack 1 is housed in the frame 11 and comes into contact with the inner wall surface of the frame 1. FIG. 5 shows an example of the frame 11.
The frame body 11 has four frame sides 4a, 4b, 4c, and 4d that extend linearly. The frame side portions 4a to 4d are arranged to face the first fixing portions 5a, 5b and the second fixing portions 5c, 5d, respectively. The frame body 11 is manufactured, for example, by combining four frame members forming the frame sides 4a to 4d. The frame material is produced using, for example, a galvanized iron plate, a stainless steel plate, resin, wood, or the like.

According to one embodiment, it is preferable that the frame 11 has a flange 11e extending inward in a direction perpendicular to the airflow direction only at one end in the airflow direction. Thereby, the filter pack 1 can be moved in the airflow direction and stored in the frame 11 from the side opposite to the side in the airflow direction where the flange 11e is provided, and furthermore, the flange 11e and the filter pack 1 By abutting against each other, the space between the frame body 11 and the filter pack 1 can be kept more airtight. In addition, in the frame 11 of the example shown in FIG. 4, illustration of a protruding portion extending outward in a direction orthogonal to the airflow direction is omitted at the downstream end in the airflow direction.

In the air filter of this embodiment, the Y direction of the second fixing parts 5c and 5d of the filter pack 1 follows the shape of the frame side parts 11c and 11d under the force of the filter medium 3 which tends to widen the pleat interval. It's deformed. That is, the second fixing parts 5c and 5d extend linearly without being bent. In such an air filter, the second fixed parts 5c and 5d transmit the force of the filter medium 3, which tends to widen the pleat interval, to the inner wall surface of the frame 11, so that the second fixed parts are flexible. The effect of suppressing the formation of a gap between the second fixing portions 5c, 5d and the frame body 11 is greater than that in the case where the fixing portions do not have any properties.

The frame body 11 is not limited to the illustrated form. The frame body 11 may be, for example, a duct provided in a building or a mounting frame provided in an air conditioning room.
The air filter of this embodiment is suitably used in facilities such as factories, workshops, and kitchens, and is preferably used in places where there is a large amount of dust floating in the air.

Although the filter pack and air filter of the present invention have been described in detail above, the air filter and filter pack of the present invention are not limited to the above embodiments, and various improvements and changes can be made without departing from the gist of the present invention. Of course you can.

1 Filter pack 3 Filter medium 3a Fold line 6 Structure 6a Sheet 6b Rib 10 Air filter 11 Frame 11a, 11b, 11c, 11d Frame side 11e Flange

Claims (7)

A filter pack,
A pleated filter material that collects fine particles in the gas,
a surrounding member that circumferentially surrounds the filter medium so that the folds of the pleats are exposed;
The surrounding member is
two first fixing parts fixed to the filter medium so as to sandwich the filter medium from both sides in the extending direction of the fold;
two second fixing parts fixed to the filter medium so as to sandwich the filter medium from both sides in a direction perpendicular to the direction in which the folds extend and the direction of airflow passing through the filter medium;
When the filter pack is compressed or expanded in the orthogonal direction so that the interval between adjacent pleats changes, the amount of displacement of the second fixing part along the orthogonal direction is equal to the amount of displacement of the second fixing part in the orthogonal direction. The larger the part of the second fixing part is, the further away from the
The length of the filter pack along the orthogonal direction is such that the amount of displacement of the second fixing part is greater at the first position in the direction parallel to the extending direction of the fold than at the first position. longer than the smaller second position;
Each of the fixing parts has a plate-shaped structural material made of plastic,
The structural material is
two sheets facing each other,
a plurality of ribs extending in one direction and spaced apart from each other, each of the ribs being arranged in parallel to each other to form a plurality of spaces surrounded by the ribs and the sheet and extending in one direction; has a plurality of ribs connecting the two sheets,
A filter pack characterized in that the second fixing portion has an out-of-plane bending strength of 3.0 N/mm ² or less . The filter pack according to claim 1 , wherein in the second fixing portion, the rib extends in the direction in which the fold line extends. 3. The filter pack according to claim 1 , wherein in the first fixing part, the rib extends in the orthogonal direction. The filter pack according to any one of claims 1 to 3 , wherein the surrounding member further includes a covering member that covers the structural material. The filter medium has a pair of protrusions provided in adjacent pleated portions of the filter medium so as to come into contact with each other when the filter medium is folded, according to any one of claims 1 to 4 . filter pack. The filter pack according to any one of claims 1 to 5 , wherein the filter medium is not provided with a reinforcing material extending over the tops of the pleats so as to extend in the orthogonal direction. A filter pack according to any one of claims 1 to 6 ,
a frame body in which the filter pack is housed and comes into contact with the filter pack;
The frame body has four frame side parts arranged to face each of the first fixing part and the second fixing part,
The air filter is characterized in that the second fixing part deforms along the shape of the frame side part in response to the force of the filter medium that causes the interval between adjacent pleats to widen.

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