JP2016068041A - Charging filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain excellent collection efficiency at an air supply opening of a building while suppressing pressure loss.SOLUTION: A charging filter according to one embodiment is a charging filter fitted to an air supply opening for supplying air from outside a building into a room and including a first layer and a second layer such that the first layer comprises a base and a plurality of solid projections extending from a surface of the base and adjoining the second layer, the projections each have a stem part having a root-side side face and a tip-side side face, and the second layer has a base, a first angle that the root-side side face of the stem part and the base of the first layer contain being equal to or larger than 90° to less than 180°, a second angle that the tip-side side face of the stem part and the base of the second layer contain being equal to or larger than 45° to less than 180°, and a thickness being 3 to 15 mm.SELECTED DRAWING: Figure 10

Description

  One aspect of the present invention relates to a charging filter attached to an air supply opening of a building.

  2. Description of the Related Art Conventionally, an air supply port that supplies air from the outside of a building to a room and includes a filter for collecting dust in the air is known. For example, Patent Document 1 describes an air supply device that includes a dustproof filter that is exchangeably filled from the indoor side, and a stopper for removing and draining the dustproof filter. Moreover, patent document 2 describes the air supply shutter provided with the filter arrange | positioned in the back surface of a main body cover so that ventilation is possible.

JP 2007-139385 A JP 2010-249368 A

  In general, the filter attached to the air inlet of a building is a mesh filter that prevents intrusion of foreign matters (for example, dead leaves and insects) of 1 mm or more, but this mesh filter is made of pollen, sand dust, exhaust gas, It cannot collect fine particles such as smoke. Therefore, a nonwoven fabric filter that can be attached to the air supply port is provided. However, if the weight of the nonwoven fabric filter is increased in order to increase the collection efficiency, the pressure loss increases, and the outdoor air is sufficiently exhausted indoors. It will not be possible to import. Therefore, there is a demand for a filter that can obtain good collection efficiency at the air supply port of a building while suppressing pressure loss.

  A charging filter according to one aspect of the present invention is a charging filter including a first layer and a second layer, which is attached to an air supply port that supplies air from the outside of a building to a room, and includes the first layer. Comprises a base and a plurality of solid protrusions extending from the surface of the base and adjacent to the second layer, the protrusion having a stem having a root side surface and a tip side surface; The layer includes a base, the first angle formed by the base side surface of the stem and the base of the first layer is 90 ° or more and less than 180 °, and the tip side surface of the stem and the base of the second layer The second angle formed by is less than or equal to 45 ° and less than 180 °, and the thickness is 3 to 15 mm.

  In such a side surface, by ensuring a wide angle between the stem portion and the base (first angle) and an angle (second angle) formed between the stem portion and the base of the second layer, Air also flows in the vicinity of the corners forming the channel (near the root side surface and the tip side surface of the stem), and fine particles can also be collected at the corners. In addition, the inventors have found that the pressure loss and the collection efficiency can be balanced by setting the filter thickness, that is, the flow path length to 3 to 15 mm. That is, in such a side surface, it is possible to obtain good collection efficiency at the air supply port of the building while suppressing pressure loss.

  According to one aspect of the present invention, it is possible to obtain good collection efficiency at an air supply port of a building while suppressing pressure loss.

It is a perspective view of the sheet | seat (layer) used for the charging filter which concerns on embodiment. (A), (b) is a side view of the protrusion on a sheet | seat together. It is a figure for demonstrating projection of the processus | protrusion to a virtual surface. It is a figure which shows some examples of the projection image of a processus | protrusion. It is a figure which shows some examples of the projection image of a processus | protrusion. It is a figure which shows some examples of the projection image of a processus | protrusion. It is a figure which shows some examples of the projection image of a processus | protrusion. It is a figure which shows the example of the slit formed in the sheet | seat. It is a figure which shows the example of the opening formed in the sheet | seat. It is the perspective view and partial enlarged view of the charging filter which concern on embodiment. It is a perspective view of the air supply opening | mouth to which the charging filter which concerns on embodiment is attached. It is the XII-XII sectional view taken on the line of FIG. It is a disassembled perspective view of the air supply port which concerns on embodiment. It is the XIV-XIV sectional view taken on the line of FIG. It is a graph which shows the result of the pressure loss in an Example and a reference example. It is a graph which shows the result of the collection efficiency in an Example and a reference example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

  First, the structure of the charging filter according to the embodiment will be described with reference to FIGS. The term “filter” in the present specification is an apparatus or a part for removing fine particles (a minute solid or foreign matter) mixed in a gas. In the present embodiment, it is assumed that the gas is air. Examples of the fine particles include dust, dust, and pollen, but the object to be removed by the charge filter is not limited to these, and the charge filter may remove any fine particles in the gas. The charging filter according to the present embodiment is attached to an air supply port that supplies air into the room from the outside of the building.

  The charging filter includes a plurality of layers. At least some of the plurality of layers are formed by the sheet 10 shown in FIG. The sheet 10 is a thin plate-like member, and includes a base 11 and a plurality of solid protrusions 20 disposed on the base 11. The term “projection” in the present specification is a structure that extends outward from one surface of the base 11. Further, in this specification, the surface on which the protrusions 20 are present is defined as the surface of the layer, the sheet 10 or the base 11, and the surface on which the protrusions 20 are not present is defined as the layer, the sheet 10, Alternatively, it is defined as the back surface of the base 11.

  The dimension of the sheet 10 (layer) is set according to the dimension of the charging filter. The size of the charging filter varies. The charging filter according to the present embodiment is produced by winding at least one sheet 10 to obtain a roll, and cutting the roll in a direction orthogonal to the winding core, and exhibits a roll shape (details will be described later). ). The length and width of the sheet 10 can take various values. For example, the length and width of the sheet 10 can take values in various ranges from several centimeters to several tens of meters. On the other hand, the thickness of the sheet 10 is set in consideration of, for example, both a dust removal effect (dust collection effect) and securing a gas flow path, but the thickness is not limited at all. Here, the thickness of the sheet 10 is a distance from the back surface of the base 11 to the highest point of the protrusion 20. As an example, the lower limit of the thickness of the sheet 10 may be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm, and the upper limit is 3.0 mm, 2.5 mm, 2.0 mm, 1 .5 mm or 1.0 mm may be used.

  As shown in FIG. 2A, the protrusion 20 of this embodiment includes at least a stem portion 21 extending from the surface of the base 11. As shown in FIG. 2B, the projection 20 may include an umbrella portion 22 formed at the tip of the stem portion 21. In this case, the projection 20 has a bowl shape as a whole. However, the shape of the protrusion 20 is not limited to the example of FIG. 2, and various shapes can be considered as will be described later. The upper surface of the protrusion 20 (that is, the upper surface of the stem portion 21 or the umbrella portion 22) may be flat or wavy (that is, jagged).

The dimensions of the base 11 and the protrusion 20 are not limited. For example, the thickness of the base 11, the height of the protrusion 20, the height of the stem 21, the maximum width of the bottom of the stem 21, the width of the tip of the stem 21, the maximum width of the umbrella 22, and the stem 21 All the overhang amounts of the umbrella part 22 may be set arbitrarily. For example, the lower limit of the thickness of the base 11 may be 0.1 mm, and the upper limit thereof may be 0.3 mm. The lower limit of the height of the protrusion 20 may be 0.2 mm or 0.3 mm, and the upper limit may be 0.5 mm or 0.7 mm. Further, the density of the protrusions 20 on the base 11 is not limited at all. For example, the lower limit of the density of the protrusions 20 may be 139 / cm ² and the upper limit may be 760 / cm ² . The lower limit of the distance between the protrusions (the distance between the centers of the protrusion bases) may be 0.36 mm, and the upper limit may be 0.85 mm or 0.80 mm.

  The material of the sheet 10 is a thermoplastic resin, for example, polypropylene resin (PP), polyethylene resin (PE), vinyl chloride resin (PVC), ethyl methyl methacrylate resin (EMMA), ethyl acrylate resin (EA), And ethylene-vinyl acetate copolymer (EVA) resin, or a mixture of two or more thereof (for example, a mixture of polypropylene resin (PP) and polyethylene resin (PE), polypropylene resin (PP) and ethyl methyl methacrylate resin (EMMA) ), Polypropylene resin (PP) and ethyl acrylate resin (EA), polypropylene resin (PP) and ethylene-vinyl acetate copolymer (EVA) resin, polyethylene resin (PE) and ethyl methyl・ Methacrylate resin ( Mixture of MMA), a mixture of polyethylene resin (PE) and ethyl acrylate resin (EA), polyethylene resin (PE) Ethylene - a mixture of vinyl acetate copolymer (EVA) resin). Examples of PE include low density polyethylene (LDPE), high density polyethylene (HDPE), and linear low density polyethylene (LLDPE). A resin having a hardness corresponding to the shape of the protrusion 20, a mixing ratio, and the like can be selected. Moreover, an additive etc. can be added to these resin as needed.

  In the present embodiment, two examples of the manufacturing method of the sheet 10 are shown.

  One is a method described in JP-T-2005-514976. In this method, first, a plurality of rail-shaped ribs having a cross-sectional shape of protrusions are formed on a base sheet by extruding a thermoplastic resin from an extrusion die having an opening cut by electronic discharge machining. Lined strips are formed. Subsequently, the strip is pulled with a roller in a cooling tank filled with a cooling liquid such as water. Subsequently, a plurality of portions corresponding to the thicknesses of the protrusions are formed for each rib by cutting in the width direction in each rib at a plurality of positions separated from each other along the longitudinal direction of the rib. After cutting the ribs, the strip base sheet is stretched at a predetermined stretch ratio. Specifically, the base sheet is stretched along the longitudinal direction of the rib between a first pair of nip rollers and a second pair of nip rollers driven at different surface speeds. In this step, one of the first pair of nip rollers located upstream is heated to heat the base sheet, while one of the second pair of nip rollers located downstream is cooled to remove the base sheet. It may be stabilized. By this extension, a space is generated between a plurality of portions of the rib, and the portion becomes the protrusion 20.

  Another example is the technique described in JP-T-2008-532699. In this method, first, a strip-like base material in which a plurality of columnar bodies forming a plurality of projections are arranged on the surface is formed by extrusion using a template having a large number of through holes or an extruder. In addition, the protrusion which has an umbrella part can be formed by crushing the front-end | tip part with a calender roll, heating the front-end | tip part of each columnar body. One sheet 10 is obtained by this process.

  The sheet 10 is subjected to electret treatment, whereby each layer functions as a charged layer. The electret process is a process of charging the sheet 10 by corona discharge, heating and cooling, charged particle spraying, or the like. By charging the sheet 10, the effect of dust removal or filtration of each layer can be enhanced.

  Various shapes of the protrusion 20 will be described below. The feature of the shape of the protrusion 20 can be found when the protrusion 20 is viewed from the side. In the present embodiment, as shown in FIG. 3, the feature of the shape of the protrusion 20 is shown using the outer edge of the projection image P obtained by projecting the protrusion 20 onto the virtual plane V orthogonal to the base 11. The virtual plane V is set so as to intersect the direction in which the gas flows, which means that the virtual plane V is set in such a manner as to block the gas flow. 4 to 7 are projection images of various protrusions 20. In these drawings, the same reference numerals as those assigned to the protrusions are attached to the projection images for easy understanding. The first outer edge 23 and the second outer edge 24 of the projection image shown in FIGS. 4 to 7 are both outer edges corresponding to the side surfaces of the stem 21. In the present embodiment, of the side surfaces of the stem portion 21, a part including the connection portion with the base 11 is referred to as “root side surface”, and a part including the tip of the stem portion 21 is referred to as “tip side surface”. 4-7, the lower base 11 corresponds to the base of the first layer, the stem 21 (protrusion 20) corresponds to the protrusion of the first layer, and the upper base 11 (adjacent). The base 11) of the layer corresponds to the base of the second layer.

  In the pattern 1, the stem portion 21 has a tapered shape that narrows toward the tip. Neither the first outer edge 23 nor the second outer edge 24 is bent or curved and is straight. The first angle θ formed by the base 11 and the root side surface of the stem 21 is an obtuse angle. On the other hand, the second angle φ formed by the side surface on the tip side of the stem portion 21 and the base 11 of the adjacent layer is an acute angle, but is set to 45 ° or more. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20. Here, the diameter of the tip portion (or root portion) of the protrusion 20 in this specification is the maximum value of the length of the tip portion (or root portion) along the extending direction of the base 11.

  The pattern 2 shows the protrusion 20 in which the umbrella part 22 was provided in the front-end | tip of the stem part 21 shown by the pattern 1. FIG. In the present specification, regardless of whether or not the umbrella portion 22 is provided, the second angle φ indicating the shape of the corner of the flow path is such that the tip side surface of the stem portion 21 and the base 11 of the adjacent layer are Therefore, this pattern 2 is also an acute angle of 45 ° or more. Thus, the presence of the umbrella portion 22 does not affect the determination of the second angle φ. On the other hand, the diameter of the tip of the protrusion 20 having the umbrella portion 22 is the diameter of the umbrella portion 22 (the maximum value of the length of the umbrella portion 22 along the extending direction of the base 11). When the umbrella portion 22 is provided, the relationship that the diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20 is also established in the protrusion 20. The following pattern is described based on the aspect of the protrusion 20 that does not have the umbrella part 22, but the aspect that has the umbrella part 22 can be considered similarly to the pattern 2.

  In Pattern 3, the stem portion 21 has a tapered shape that narrows toward the tip. Both the first outer edge 23 and the second outer edge 24 are curved so that the entirety thereof is convex toward the inside of the projection image. A first angle (an angle formed between the base 11 and the auxiliary line M) θ formed by the base 11 and the root side surface of the stem portion 21 is an obtuse angle. On the other hand, the second angle φ formed by the side surface on the distal end side of the stem portion 21 and the base 11 of the adjacent layer is 90 °. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

  In the pattern 4, the stem portion 21 has a shape such that the central portion in the extending direction is narrowed. Both the first outer edge 23 and the second outer edge 24 are curved so that the entirety thereof is convex toward the inside of the projection image. A first angle (an angle formed between the base 11 and the auxiliary line M) θ formed by the base 11 and the root side surface of the stem portion 21 is an obtuse angle. Further, the second angle (angle formed by the auxiliary line N and the adjacent base 11) φ formed by the tip side surface of the stem 21 and the base 11 of the adjacent layer is also an obtuse angle. When the angles of all the corners of the flow path are obtuse, the gas can pass more easily near all the corners of the flow path, so that the pressure loss of the charging filter can be further suppressed, and the minute amount in the gas can be reduced. It is also possible to collect more particles. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

  In the pattern 5, the stem portion 21 has a shape such that the central portion in the extending direction is narrowed. The entire first outer edge 23 is formed in a straight line and is bent so as to be convex toward the inside of the projection image. The second outer edge 24 has the same shape as the first outer edge 23. The first angle θ formed by the base 11 and the root side surface of the stem 21 is an obtuse angle. Further, the second angle φ formed by the side surface on the distal end side of the stem portion 21 and the base 11 of the adjacent layer is also an obtuse angle. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

  In the pattern 6, the root side of the stem portion 21 has a straight column shape, and the remaining portion of the stem portion 21 has a tapered shape that narrows toward the tip. The root sides of the first outer edge 23 and the second outer edge 24 are straight lines. On the other hand, the front end sides of the first outer edge 23 and the second outer edge 24 are curved so as to be convex toward the outside of the projection image. The first angle θ formed by the base 11 and the root side surface of the stem 21 is 90 °. The second angle (angle between the auxiliary line M and the adjacent base 11) φ formed by the side surface on the tip side of the stem portion 21 and the base 11 of the adjacent layer is an acute angle of 45 ° or more. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

Patterns 7 and 8 are examples in which the projected image of the stem 21 is not line symmetric. In the pattern 7, the stem portion 21 has a tapered shape that narrows toward the tip. Neither the first outer edge 23 nor the second outer edge 24 is bent or curved and is straight. First angle theta _a formed by the (root side side surface of the stem portion 21) the root side of the base 11 and the first outer edge 23 is obtuse. First angle theta _b formed by the (root side side surface of the stem portion 21) the base 11 and the base side of the second outer edge 24 is 90 °. The distal end side of the first outer edge 23 (the leading end side surface of the stem 21), the second angle phi _a formed between the base 11 of the adjacent layers is the acute 45 ° or more. The distal end side of the second outer edge 24 (the leading end side surface of the stem 21), the second angle phi _b forming the base 11 of the adjacent layers is 90 °. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

In the pattern 8, the stem portion 21 has a tapered shape that narrows toward the tip. The first outer edge 23 is curved so that the entire outer edge 23 is convex toward the inside of the projection image. On the other hand, the second outer edge 24 is curved so that the entire outer edge 24 is convex toward the outside of the projection image. Theta _a (angle between the base 11 and the auxiliary line M _a) a first angle formed by the (root side side surface of the stem portion 21) the root side of the base 11 and the first outer edge 23 is obtuse. Base 11 and the theta _b (angle between the base 11 and the auxiliary line M _b) a first angle formed by the (root side side surface of the stem portion 21) the second base side of the outer edge 24 is 90 °. The distal end side of the first outer edge 23 (the leading end side surface of the stem 21), the second angle phi _a formed between the base 11 of the adjacent layers is also 90 °. The distal end side of the second outer edge 24 (the leading end side surface of the stem 21), phi _b (angle of the base 11 adjacent the auxiliary line N) a second angle between the base 11 of the adjacent layers is 45 A sharp angle of more than °. The diameter Lt of the tip portion of the protrusion 20 is smaller than the diameter Lb of the root portion of the protrusion 20.

  In each of the patterns 1 to 8, the first angle θ is set to 90 ° or more and less than 180 °, the second angle φ is set to 45 ° or more and less than 180 °, and the diameter of the tip of the protrusion 20 is the protrusion 20. It is smaller than the diameter of the root part. As long as these conditions regarding the first angle θ, the second angle φ, and the diameter of the protrusion 20 are satisfied, the shapes of the protrusion 20 and the stem portion 21 are not limited. The lower limit of the first angle may be 100 °, 110 °, 120 °, 130 °, 140 °, 150 °, 160 °, or 170 °, and the upper limit is 100 °, 110 °, 120 °, 130 °, 140 It may be °, 150 °, 160 °, or 170 °. The lower limit of the second angle may be 50 °, 60 °, 70 °, 80 °, 90 °, 100 °, 110 °, 120 °, 130 °, 140 °, 150 °, 160 °, or 170 °. The upper limit may be 50 °, 60 °, 70 °, 80 °, 90 °, 100 °, 110 °, 120 °, 130 °, 140 °, 150 °, 160 °, or 170 °.

  The first angle θ and the second angle φ are angles corresponding to the shape of the gas flow path (space), more specifically, the angles of the corners of the gas flow path, and are solid stems. Note that this is not an angle with respect to part 21 itself. Here, each “flow path” in the present specification is a space formed between two adjacent protrusions 20. The angles θ and φ are measured in the projected image of the protrusion 20. By setting the angle of the corner of the flow path to an obtuse angle, a right angle, or an acute angle of 45 ° or more, the gas also flows near each corner. Pressure loss can be suppressed. Further, since the gas also passes in the vicinity of the corner of the flow path, minute particles in the gas can be collected even at the corner of the flow path or a portion near the corner. As described above, the angles θ and φ are important factors that influence the ease of gas flow and the value of pressure loss, and can also affect the filtering efficiency.

  In each of the patterns 1 to 8, the tip portion of the protrusion 20 is set to be thinner than the root portion of the protrusion 20, and the root side surface of the stem portion 21 is orthogonal to the base 11 or toward the tip. It is formed so as to be constricted. By forming the protrusion 20 in this manner, when the roll is formed by winding the sheet 10, the tip portion of the protrusion 20 is flexibly deformed according to the pressure from the adjacent layer. Variation is alleviated. As a result, winding tightening and winding looseness are less likely to occur, and variations in tension are suppressed in the roll or the entire charging filter obtained by cutting the roll, so that it is difficult for the charging filter to collapse. .

  The shape of the upper surface (the upper surface of the stem portion 21 or the upper surface of the umbrella portion 22) of the protrusion 20 substantially parallel to the base 11 may be arbitrarily determined. For example, the shape of the upper surface may be a circle, an ellipse, a rectangle, or a star. Or the shape of the upper surface may be arbitrary polygons, such as a triangle and a hexagon, and may be a more complicated shape.

  The specific arrangement mode of the plurality of protrusions 20 on the base 11 is not limited. For example, the protrusions 20 may be arranged in a lattice shape, may be arranged in a staggered manner, or may be randomly arranged. The protrusions 20 may be evenly arranged on the base 11 or may be unevenly arranged. For example, in the base 11, a protrusion region where the protrusion 20 exists and a flat region where the protrusion 20 does not exist may be mixed. Alternatively, in one base 11, a region where the protrusions 20 are dense (a dense region) and a region where the protrusions 20 are sparse (a sparse region) may be mixed. The arrangement | positioning aspect of the processus | protrusion 20 is not limited to these, What kind of pattern may be sufficient if a gas flow path can be formed. Further, protrusions having different shapes (patterns) may be provided on one base 11.

  A slit or opening may be formed in the base 11. The term “slit” in this specification is a concept including a slit-like groove or a slit-like through portion. The term “groove” in the present specification indicates a state in which a notch provided on one surface of the base 11 does not penetrate the other surface. This groove may be formed on the surface of the base 11 or on the back surface. The term “penetrating portion” in this specification indicates a state in which a hole or opening provided in the base 11 penetrates from one surface to the other surface. In the present specification, the slit-like groove and the slit-like through portion are collectively referred to as “slit”. In the present embodiment, a linear slit is shown, but the shape of the slit is arbitrary. For example, a slit having a wave shape, a mountain shape, an uneven shape, or the like may be formed in the base 11. FIG. 8 shows an example of the slit 13 formed in the base 11, and FIG. 9 shows an example of the opening 14 formed in the base 11. The modes of the slit and the opening are various as described below.

  The slit can be formed by any conventionally used method (for example, a blade or laser cutting). On the other hand, the opening can be formed by, for example, expanding the base 11 on which the slit-shaped through portion is formed in a direction orthogonal to the slit row. Examples of means for expanding the base 11 include machines such as tenters and rollers, and manual work. Alternatively, the opening may be formed by cutting the base 11 into a desired shape without expanding the base 11.

  The arrangement of the slits is arbitrary. For example, slits extending without interruption from one side of the base 11 to the other side may be arranged at a predetermined interval. Or a slit may be arrange | positioned at zigzag form and may be arrange | positioned at grid | lattice form. Further, it is not necessary that the density of the slits is constant throughout the base 11, and there may be a portion where the slits are sparse and a portion where the slits are dense in one base 11.

  The length of each slit is not limited. Moreover, the length of each slit may be unified in the one base 11, and the slit of a different length may be mixed. The interval between the two adjacent slits in the extending direction of the slit is not limited, and the interval between the two adjacent slits in the direction orthogonal to the extending direction is not limited. Further, these intervals may or may not be unified in one base 11.

  The slit may extend so as to be parallel to one side of the base 11 or may be formed to be inclined at an arbitrary angle θ (0 ° <θ <90 °) with respect to the side of the base 11.

  The arrangement of the openings is also arbitrary. For example, openings that extend without interruption from one side of the base 11 to the other side may be arranged at a predetermined interval. The openings may be arranged in a staggered pattern or in a grid pattern. In one base 11, a portion with a sparse opening and a portion with a dense opening may be mixed. The interval between two adjacent openings is not limited, and the interval may or may not be unified. Further, the opening may be formed obliquely with respect to the side of the base 11. As described above, as for the arrangement of the openings, various modifications can be considered as in the case of the slits.

  The shape of the opening is not limited, and may be, for example, a rectangle, a diamond, a circle, an ellipse, a rectangle, a star, a waveform, or another polygon. Also, a plurality of shapes of openings may be mixed in one base 11.

  A slit and an opening may be mixed. Of course, the arrangement of the individual slits and openings may be arbitrarily determined.

  FIG. 10 shows a charging filter 100 according to this embodiment. This charging filter 100 is obtained by winding at least one belt-like sheet 10 around a cylindrical core 101 (that is, a core having a through hole). Alternatively, the charging filter 100 is obtained by cutting a roll obtained by winding at least one sheet 10 around the core 101 in a direction orthogonal to the extending direction of the core 101. Alternatively, a roll obtained by spirally winding at least one sheet 10 may be used as the charging filter 100 having a plurality of layers. Alternatively, the charging filter 100 may be obtained by winding a plurality of sheets having different characteristics (for example, the shape or arrangement of protrusions). The charging filter 100 has a large number of flow paths 90 through which a gas flows (see an enlarged portion in FIG. 10). A portion around which the sheet 10 is wound (a portion where a large number of flow paths 90 exist) is a filter layer 102 having a dust collecting function.

  When the slit or opening is formed in the base 11, the rigidity of the sheet 10 itself is reduced, and the sheet 10 is deformed more flexibly. Therefore, the work of winding the sheet 10 small becomes easy and adjacent. The charging filter 100 in which the two layers are more closely attached can be manufactured. By adjusting the size or shape of the slit or opening formed in the sheet 10, the flexibility of the sheet 10 can be appropriately changed according to the attribute (production method, application scene, etc.) of the charging filter.

  The diameter of the charging filter 100 is set so as to match the diameter of the flow path of the air supply port. Further, the thickness of the charging filter 100 is set in consideration of the balance between the collection efficiency of the air supply port and the pressure loss. The thickness of the charging filter 100 is the length of the charging filter 100 along the direction in which the core 101 extends. When the charging filter 100 obtained by winding the sheet 10 is provided at the air supply port of a building, the charging filter has a good balance between the collection efficiency and the pressure loss by setting the thickness of the charging filter to, for example, 3 to 15 mm. Can take. For example, the lower limit of the thickness of the charging filter may be 3 mm or 5 mm, and the upper limit thereof may be 15 mm or 10 mm.

  A method for fixing the roll and the charging filter 100 is not limited. For example, the sheet 10 may be wound after an adhesive or an adhesive is applied to the upper surface of the protrusion 20. Or you may use only the film (shrink film) which has contractility, without using an adhesive and an adhesive agent. Specifically, the charging filter 100 (or roll) is fixed by covering the outer peripheral surface of the charging filter 100 (or roll) with a shrink film. For example, when a heat-shrinkable tube is employed as the shrink film, the heat-shrinkable tube is disposed on the outer peripheral surface of the charging filter 100 (or roll), and then the tube is heated, so that the tube shrinks and the charging filter 100 Press (or roll) from the outside. Examples of heat shrink tube materials include polyethylene terephthalate (PET) and biaxially oriented polystyrene (BOPS). Alternatively, the charging filter 100 (or roll) may be pressed from the outside by winding the charging filter 100 (or roll) with the shrink film while applying tension to the shrink film. By fixing the charging filter 100 only by the shrink film, the charged state of each layer of the charging filter 100 can be kept good.

  When the charging filter is viewed toward the inlet or outlet of the charging filter, the protrusions 20 may be aligned along the stacking direction, arranged in a staggered manner, or randomly arranged. Good.

  The charging filter may include a plurality of different types of layers. For example, the charging filter may include a layer (additional functional layer) other than the layer (basic layer) formed by the sheet 10. For example, the additional functional layer may be activated carbon that removes or deodorizes organic components, an absorbent such as zeolite or aluminosilicate, or a deodorization catalyst such as copper-ascorbic acid. Alternatively, the additional functional layer may be a desiccant such as silica gel, zeolite, calcium chloride or activated alumina, a disinfectant such as a UV sterilization system, or a fragrance such as gloxal, methacrylate or a fragrance. Alternatively, the additional functional layer is made of Mg, Ag, Fe, Co, Ni, Pt, Pd or Rn, or a metal such as an oxide supported on a support such as alumina, silica alumina, zirconia, diatomaceous earth, silica zirconium or titania. An ozone removing agent containing One charging filter may include a plurality of types of additional functional layers.

  Next, the structure of the air supply port 200 to which the charging filter 100 is attached will be described with reference to FIGS. 11 is a perspective view of the air supply port 200, FIG. 12 is a cross-sectional view taken along line XII-XII of FIG. 11, FIG. 13 is an exploded perspective view of the air supply port 200, and FIG. It is XIV sectional view taken on the line.

  The air supply opening 200 is an article for supplying air into the room from the outside of the building, and is generally installed on the wall surface or ceiling. The air supply port 200 includes a cylindrical main body 210 mounted in a wall or a ceiling, a support body 220 for supporting the charging filter 100 in the main body 210, and a flow path of the air supply port 200 on the indoor side. And a plate-like panel 230 that functions as a lid for opening and closing. The charging filter 100 can also be a component of the air supply port 200.

  The cylindrical portion of the main body 210 forms a flow path 211 through which air flows. The diameter of the flow path 211, that is, the diameter of the inner wall 212 of the main body 210 is usually set to 10 to 20 cm, but the diameter of the flow path is not limited to this range. A rectangular flange 213 for fixing the main body 210 to the wall surface or ceiling surface is formed at one end (inner end portion) of the main body 210, and the end portion of the main body 210 where the flange 213 exists is located on the indoor side. To be fixed on the wall or ceiling. A receiving portion 214 for receiving a shaft portion 221 of a support body 220 described later is provided at the center of the outer end portion of the main body, and the receiving portion 214 is supported by a plurality of upstream support bars 215 extending from the inner wall 212 toward the center. . The upstream support bar 215 also serves to support the upstream surface (filter main surface) 103 of the charging filter 100 that receives the incoming air. A tapered (bullet-shaped) cap 216 is attached to the outer side (outdoor side) of the receiving portion 214.

  In the present specification, the terms “inside” and “outside” are used as necessary when the air supply port 200 is described. The term “inside” means an indoor side in a scene where the air inlet 200 is attached to a building, and the term “outside” means an outdoor side in the scene.

  The support body 220 is attached to the shaft portion 221 attached so as to pass near the center of the flow path 211, a circular support frame 222 provided on the shaft portion 221 so as to be orthogonal to the shaft portion 221, and the shaft portion 221. And a plurality of small protrusions 225 that come into contact with the core 101 of the charged filter 100. The support frame 222 includes a circular outer frame 223 having a diameter smaller than the diameter of the inner wall 212, and a plurality of downstream support bars 224 extending radially from the shaft portion 221 toward the outer frame 223. The downstream support bar 224 supports the downstream surface of the filter, which is the surface opposite to the filter main surface (upstream surface) 103. The downstream surface is a surface from which air that has passed through the charging filter 100, that is, filtered air flows out.

  The panel 230 is detachably attached to the inner end portion of the support body 220. Each time the panel 230 is pushed, the length of the support body 220 with respect to the main body 210 changes along the extending direction of the flow path 211, and the flow path 211 is opened or closed. The open state of the flow path 211 may change stepwise such as “blocking → half-opening → full opening → blocking →...”.

  The user removes the support body 220 from the main body 210. At this time, the user may remove the panel 230 from the support 220. Then, the user passes the core 101 of the charging filter 100 from the outer end portion of the support body 220 through the shaft portion 221 and moves the charging filter 100 to the support frame 222 to attach the charging filter 100 to the support body 220. At this time, since the protruding portion 225 is positioned inside the core 101, the charging filter 100 is firmly fixed to the support 220, and the charging filter 100 is prevented from being displaced in the extending direction of the shaft portion 221. Then, the user attaches the support body 220 to the main body 210, and when the panel 230 is removed from the support body 220, the user attaches the panel 230 to the support body 220. At this time, the filter main surface 103 of the charging filter 100 is in contact with the upstream support bar 215, and the downstream surface of the charging filter 100 is in contact with the downstream support bar 224. That is, the charging filter 100 is fixed in a form sandwiched between the upstream support bar 215 and the downstream support bar 224. When replacing the charging filter 100, the user removes the support body 220 from the main body 210, removes the charging filter 100 from the support body 220, and then inserts a new charging filter 100 into the air inlet 200 in the same procedure as described above. It only has to be attached.

  If the collection efficiency of the charging filter 100 attached to the air supply port 200 is indicated by the collection efficiency of particles having a median particle diameter of about 0.10 μm, the collection efficiency is 60% or more, 50% or more. , 40% or more, or 30% or more.

  The pressure loss of the charging filter 100 attached to the air supply port 200 may be 5 Pa (about 0.5 mmAq) or less, 10 Pa (about 1 mmAq) or less, 20 Pa (about 2 mmAq) or less, or 30 Pa (about 3 mmAq) or less.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to them at all.

  A sheet for forming a charging filter was formed using polypropylene as a material. Each protrusion has a stem portion and no umbrella portion, and thus has a shape as shown in FIG. The projected image of the stem portion obtained by projecting onto the virtual plane corresponds to the above pattern 1 or 3. The thickness of the base was 0.1 to 0.2 mm, the height of each protrusion was 0.3 to 0.5 mm, and the maximum width of the tip of each protrusion was 0.1 to 0.2 mm. The protrusions were formed on the base so that the individual protrusions were arranged in a lattice pattern at intervals of 0.8 mm. The electret treatment on the sheet was performed using an apparatus manufactured by Wedge Inc. having a machine width of 1200 mm. The time for the heat treatment (100 ° C.) in the electret treatment was 5 seconds, the time for the cooling treatment was also 5 seconds, and the applied voltage was 13.5 KV. Four rolls with a diameter of 150 mm were prepared by winding the sheet subjected to the electret treatment into 3 mm width, 5 mm width, 10 mm width, or 15 mm width and wound on an ABS shaft having a diameter of 3 mm. In addition, the edge part of the wound sheet | seat was fixed with the tape.

The structure (height of protrusion and filter thickness) of the charging filter of Examples 1 to 7 produced by this series of treatments was as follows.
Example 1: Projection height = 0.5 mm, filter thickness = 15 mm
Example 2: Projection height = 0.5 mm, filter thickness = 10 mm
Example 3: Projection height = 0.5 mm, filter thickness = 5 mm
Example 4: Projection height = 0.3 mm, filter thickness = 15 mm
Example 5: protrusion height = 0.3 mm, filter thickness = 10 mm
Example 6: Projection height = 0.3 mm, filter thickness = 5 mm
Example 7: protrusion height = 0.3 mm, filter thickness = 3 mm

Moreover, the following three patterns of commercial products were prepared as reference examples of the charged nonwoven fabric filter that can be attached to the air supply port.
Reference Example 1: Non-woven fabric (Filterlet (registered trademark) Air Cleaner Filter Premier Grade, manufactured by 3M)
Reference Example 2: Non-woven fabric (filterlet (registered trademark) air purifying filter high grade manufactured by 3M)
Reference Example 3: Non-woven fabric (Filterlet (registered trademark) Air Cleaner Filter Standard Grade, manufactured by 3M)

The performance of these filters was evaluated using an inspection apparatus called TSI MODEL 8130. As the particles for inspection, sodium chloride having a size indicated by a count median diameter of about 0.10 μm is used, and the density of the particles in the airflow is about 50 mg / m ³ (the variation range is 15%). It was. The flow rate was 20 to 80 cm / second. The inspection time was defined as the time until 100 mg of sodium chloride was provided in the air stream.

The filtration efficiency E (%) is expressed by the following formula, where the particle concentration in the airflow before passing through the filter is Ca (mg / m ³ ), and the particle concentration (mg / m ³ ) in the airflow after passing through the filter is Cb. can get.
E = (Ca−Cb) / Ca × 100

  Table 1 shows the pressure loss (mmAq) and the collection efficiency (%) when the flow rate is 20 cm / sec. Note that 1 mmAq = 9.80665 Pa (about 10 Pa).

  About pressure loss, when it is 2.0 mmAq (about 20 Pa) or less, it is evaluated as “Excellent”, which exceeds 2.0 mmAq (about 20 Pa) and 3.0 mmAq (about 30 Pa) or less. When it was, it was evaluated as “Acceptable”, and when it exceeded 3.0 mmAq (about 30 Pa), it was evaluated as “No good”. If the evaluation is “excellent” or “possible”, it can be said that the pressure loss requirement of the air inlet filter is satisfied.

  The collection efficiency is evaluated as “Excellent” when it is 50% or more, and “Acceptable” when it is 30% or more and less than 50%. Was less than 30%, it was evaluated as “No good”. If the evaluation is “excellent” or “possible”, it can be said that the requirements for the collection efficiency of the air inlet filter are satisfied.

Table 2 shows the pressure loss (mmAq) and the collection efficiency (%) when the flow rate is 50 cm / sec.

Table 3 shows the pressure loss (mmAq) and the collection efficiency (%) when the flow rate is 80 cm / second.

  Note that the pressure loss at the air supply port equipped with a charging filter is greatly influenced by the shape and structure of the air supply port, so it is always determined only by the indicators of “excellent”, “good”, and “bad”. is not.

  The graphs of Tables 1 to 3 are shown in FIGS. FIG. 15 is a graph showing the results of pressure loss in Examples 1 to 7 and Reference Examples 1 to 3. FIG. 16 is a graph showing the collection efficiency results of Examples 1 to 7 and Reference Examples 1 to 3. The horizontal axis in FIG. 15 is the flow velocity (cm / sec), and the vertical axis is the pressure loss (mmAq). The horizontal axis in FIG. 16 is the flow velocity (cm / second), and the vertical axis is the collection efficiency (%).

  As described above, the charging filter according to one aspect of the present invention is a charging filter including a first layer and a second layer, which is attached to an air supply port for supplying air from the outside of a building to the room. The first layer includes a base and a plurality of solid protrusions extending from the surface of the base and adjacent to the second layer, and the protrusion includes a stem portion having a root side surface and a tip side surface. And the second layer has a base, the first angle formed by the root side surface of the stem and the base of the first layer is 90 ° or more and less than 180 °, The second angle formed by the base of the second layer is 45 ° or more and less than 180 °, and the thickness is 3 to 15 mm.

  An air supply port according to one aspect of the present invention includes the above-described charging filter.

  In such a side surface, by ensuring a wide angle between the stem portion and the base (first angle) and an angle (second angle) formed between the stem portion and the base of the second layer, Air also flows in the vicinity of the corners forming the channel (near the root side surface and the tip side surface of the stem), and fine particles can also be collected at the corners. In addition, the inventors have found that the pressure loss and the collection efficiency can be balanced by setting the filter thickness, that is, the flow path length to 3 to 15 mm. That is, in such a side surface, it is possible to obtain good collection efficiency at the air supply port of the building while suppressing pressure loss.

  In the charging filter according to another aspect, the thickness may be 5 to 10 mm.

  By setting the thickness of the charging filter to 5 to 10 mm, it is possible to further balance the pressure loss and the collection efficiency.

  In the charging filter according to another aspect, the collection efficiency of particles having a median particle diameter of about 0.10 μm may be 30% or more.

  By using a charging filter that satisfies such a collection efficiency, the dust collection efficiency of the air supply port of the building is improved.

  In the charging filter according to another aspect, the pressure loss may be 30 Pa or less.

  By using a charging filter that satisfies such a standard regarding pressure loss, air can be smoothly fed into the room.

  The present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above embodiment. The present invention can be variously modified without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 10 ... Sheet | seat, 11 ... Base, 20 ... Protrusion, 21 ... Stem part, 22 ... Umbrella part, 23 ... 1st outer edge, 24 ... 2nd outer edge, 100 ... Charge filter, 101 ... Core, 102 ... Filter layer, 200 ... Air supply port, 210 ... Main body, 211 ... Flow path, 212 ... Inner wall, 215 ... Upstream support bar, 216 ... Cap, 220 ... Support body, 221 ... Shaft part, 224 ... Downstream support bar, 230 ... Panel.

Claims (5)

A charging filter including a first layer and a second layer, which is attached to an air supply port for supplying air from the outside of the building into the room,
The first layer includes a base and a plurality of solid protrusions extending from a surface of the base and adjacent to the second layer, the stem having a root side surface and a tip side surface Have
The second layer comprises a base;
The first angle formed by the base side surface of the stem and the base of the first layer is 90 ° or more and less than 180 °;
A second angle formed by the tip side surface of the stem and the base of the second layer is 45 ° or more and less than 180 °,
The thickness is 3-15 mm,
Charge filter. The thickness is 5 to 10 mm;
The charging filter according to claim 1. The collection efficiency of particles having a particle diameter median diameter of about 0.10 μm is 30% or more.
The charging filter according to claim 1 or 2. The pressure loss is 30 Pa or less,
The charging filter according to claim 1.   An air supply port comprising the charging filter according to any one of claims 1 to 4.

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