JP2004325046A - Filter unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a filter unit holding a high performance filter such as a HEPA filter, and provide efficient usage of a building facility space. <P>SOLUTION: The filter unit 2 has a positioning means 40 capable of positioning a plurality of high performance filters 1, and a holding means 50 for holding positions of the high performance filters. Air flow passing planes 11 and 12 of the high performance filter are slanted at predetermined angles α/2 and β/2 with respect to an air flow direction. An upstream side open space 3 and a downstream side open space 4 are formed between the high performance filters, or between the high performance filter and an inner wall face of a casing 21. A passage cross section of the upstream side open space expands in a direction opposite to the air flow direction and converges in the air flow direction, and a passage cross section of the downstream side open space expands in the air flow direction and converges in the direction opposite to the air flow direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a filter unit, and more particularly, to a filter unit that accommodates a high-performance filter such as a HEPA filter in a compact manner and enables efficient use of building equipment space.
[0002]
[Prior art]
Semiconductor manufacturing plants, hospitals, pharmaceutical research facilities, radioisotope (RI) handling facilities, biohazard facilities, etc. include clean rooms that require advanced special air conditioning equipment, biology laboratories, pathology laboratories, and biologically hazardous substances. A handling room and the like are provided, and in this kind of special air conditioning equipment, a high-performance filter such as a HEPA (High Efficiency Particulate Air) filter is interposed in an air supply system or an exhaust system duct (see Patent Documents 1 to 4). The HEPA filter is known as a high-performance filter capable of collecting 99.97% or more of particles having a monodisperse average particle diameter of 0.3 μm in the DOP test method. In recent years, high-performance filters, such as UPLA filters, have been put to practical use that can further improve the collection efficiency and achieve a collection efficiency of 99.9997% or more for 0.15 μm particles. In addition, there are known activated carbon filters for preventing the external release of odorous substances or radioisotopes, etc., chemical filters such as alkali adsorption filters used in museums, etc., and further, salt damage removing filters intended to prevent salt damage. I have.
[0003]
Since such a high-performance filter (hereinafter, simply referred to as “high-performance filter” in the present specification) must be replaced when the collection performance is reduced or at the time of periodic inspection, the outer dimensions of the filter are specified. In this industry, there is almost a supply system that can supply filter products to any facility at any time. For example, the dimensions of the HEPA filter are generally standardized to the standard dimensions of frame dimensions = 610 mm × 610 mm (front dimensions).
[0004]
Conventionally, this type of high-performance filter is generally used as a filter unit in which the filter is housed in a filter housing or a filter casing, and an air flow inlet and an air flow outlet of the filter unit are air-conditioning equipment, an air supply duct or Connected to the exhaust duct. If desired, a relatively large self-contained unit-type filtration device incorporating a blower in the housing is provided in an air-conditioning machine room, an exhaust system, or the like.
[0005]
[Patent Document 1] JP-A-6-304429
[0006]
[Patent Document 2] JP-A-8-42884
[0007]
[Patent Document 3] Japanese Patent Application Laid-Open No. 11-197429
[0008]
[Patent Document 4] JP-A-2002-310473
[0009]
[Problems to be solved by the invention]
In such a high-performance filter, the wind speed of the airflow passing through the filter is relatively strictly regulated in order to reliably achieve the collection efficiency. For example, in the case of the above HEPA filter, the processing air volume is generally 50 m. ³ / Min or less, and the passing wind speed (surface wind speed) is limited to 2.5 m / s or less. Further, if a gap or a minute gap is formed in the connection between the filters or the connection between the filter and the housing (or casing), untreated air that does not pass through the filter medium of the filter may leak to the downstream side. Also, the amount of leakage of the filter unit is also strictly regulated. Due to the limitation of the passing wind speed and the leak amount, the arrangement of the high-performance filters has an arrangement in which the surface wind speed is reduced and the hermetic treatment is easy, that is, the high-performance filters are arranged so as to cross the airflow direction and In general, a filter array having an airflow passage surface orthogonal to the airflow is employed.
[0010]
However, such a filter arrangement increases the overall size of the filter unit. For example, when four filters with a front dimension of 610 mm × 610 mm are arranged in the filter unit, the width dimension (inner dimension) of the filter unit is at least. It must be designed to be 2440 mm. On the other hand, the filter unit is arranged in a limited space of building equipment, such as an air-conditioning machine room or a space above a ceiling, so that a wide variety of building equipment (ducts, piping, wiring, air-conditioning equipment, plumbing sanitation equipment, electricity In the building equipment space where devices and the like are mixed, it causes pressure on or restricts the use space of other building equipment.
[0011]
The present invention has been made in view of such circumstances, and a purpose thereof is to compactly house a high-performance filter such as a HEPA filter and enable efficient use of the building equipment space. It is to provide a filter unit.
[0012]
Means and Action for Solving the Problems
In order to achieve the above object, the present invention provides a filter unit having a high-performance filter and a casing that can accommodate the filter.
Positioning means for positioning the plurality of high-performance filters in a direction in which the airflow passage surface is inclined at a predetermined angle (α / 2) with respect to the airflow direction; and holding means for holding the positions of the high-performance filters. Have
An upstream open space in which the flow path cross section expands and converges in the airflow direction in the airflow direction is formed between the high-performance filters or between the high-performance filter and the inner wall surface of the casing, A downstream open space in which the flow path section expands in the airflow direction and converges in the direction opposite to the airflow direction is formed between the high-performance filters or between the high-performance filters and the inner wall surface of the casing. The present invention provides a filter unit characterized in that:
[0013]
According to the configuration of the present invention, the high-performance filter forms an upstream open space that expands toward the upstream side, and the upstream open space opens relatively large at the upstream opening of the filter unit. Accept airflow entering the unit. The air flow is diverted in the upstream open space and passes through a high-performance filter. The high-performance filter also forms a downstream open space that expands toward the downstream side, and the downstream open space is relatively large at the downstream opening of the filter unit, and the airflow that has passed through the filter medium of the high-performance filter. Is deflected in the downstream open space and flows out to the downstream flow path. In such a filter arrangement, the surface wind speed of the airflow passage surface is greatly reduced for the same airflow as compared with a conventional filter unit in which the airflow passage surface is arranged in a direction orthogonal to the airflow. Conversely, when the surface wind speed is set to the same surface wind speed as that of the conventional filter unit, the processing air volume can be greatly increased.
[0014]
Further, in the filter unit having the above-described configuration, the proximity between the high-performance filters or the proximity between the high-performance filter and the inner wall surface of the casing is formed at the converging portion of the open space. Can be airtight.
[0015]
Therefore, according to the filter unit of the present invention, the width or the area of the cross section orthogonal to the airflow is significantly reduced for a predetermined processing air volume, and the overall size is reduced. Conversely, if there is room for the filter unit installation space, it is possible to increase the number of filters that can be arranged in substantially the same space, thereby reducing the surface wind speed of each filter, improving the collection efficiency, Alternatively, the life of the filter or the usable period can be extended.
[0016]
Note that the pressure loss of the airflow passing through the filter unit having the above configuration is expected to show a slightly increasing tendency as compared with the conventional filter unit (the airflow passage surface is arranged in a direction orthogonal to the airflow). However, such an increase in pressure loss can be compensated for by an increase in the blowing pressure. On the other hand, an increase in the amount of leak air of the filter unit is naturally expected due to such an increase in the blowing pressure. However, such a leak can be relatively easily prevented by the hermetic treatment of the adjacent portion, and The disadvantages of filter unit design and manufacture associated with this type of hermetic treatment are considered to be far less trivial than the significant benefits of the present invention of large and compact filter units.
[0017]
From another viewpoint, the present invention relates to a filtering device including the filter unit having the above configuration, wherein the filter units are vertically and horizontally aligned so that the upstream openings of the filter units face the upstream airflow. A filtering device characterized by the following.
[0018]
Such a filtering device can be significantly reduced in size as compared with a filtering device incorporating a conventional filter unit, and the installation space of the filtering device can be considerably reduced. In addition, if the filter is designed to have the same overall dimensions as the conventional filtration device, it accommodates a much larger number of filters than in the past, reduces the surface wind speed of each filter, and prolongs the life or usable period of the filter. Can be
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Preferably, the inclination angles (α / 2, β / 2) are set within an angle range of 5 to 25 degrees, and the convergence angle (α) of the upstream open space and the convergence angle (α) of the downstream open space. Are set to substantially the same angle value. More preferably, when a casing capable of accommodating a predetermined number n of high-performance filters in a state where the airflow passage surface is arranged in a direction perpendicular to the airflow direction is used, the inclination angle is at least 3 × n in the casing. The angle is set so that the high-performance filters can be accommodated.
[0020]
Preferably, the connection between the high-performance filters or the connection between the high-performance filter and the inner wall surface of the casing is subjected to airtight treatment by airtight means.
More preferably, the positioning means has a guide member that regulates an inclination angle and a position of the high-performance filter, and the holding means contacts the frame of the high-performance filter to form the frame on the guide member. It has an abutment for holding. Preferably, the holding means further includes a pressing portion that abuts against the frame of the high-performance filter and presses the frame against the guide member.
[0021]
FIG. 1 is a schematic cross-sectional view and a perspective view showing a filter arrangement according to a preferred embodiment of the present invention.
As shown in FIG. 1, a plurality of (four in the present embodiment) high-performance filters 1 are accommodated in a casing 21 of the filter unit 2. The center line C2 of the filter unit 2 is oriented in the airflow direction of the upstream airflow A and the downstream airflow B. The angle 間 の between the center line C1 of each high-performance filter 1 and the center line C2 of the filter unit 2 is set within an angle range of 65 to 85 degrees. Adjacent high-performance filters 1 are interconnected at hermetic connection portions 15 and 16, and the high-performance filter 1 and the casing 21 are connected at hermetic connection portions 17. The airtight connection parts 15, 16, 17 are vertically continuous over the entire height of the filter 1.
[0022]
The upstream open space 3 is formed between the airflow passage surfaces 11 of the adjacent high-performance filters 1. The open space 3 expands in the direction facing the upstream airflow A and converges in the airflow direction. A downstream open space 4 through which the filtered airflow B that has passed through the high-performance filter 1 flows out to the downstream flow path is formed between the airflow passage surface 12 of the high-performance filter 1 and the airflow passage surface 12 and the casing. 21 is formed. The downstream open space 4 expands in the airflow direction and converges toward the upstream flow path.
[0023]
The convergence angles α and β of the open spaces 3 and 4 are set to an angle in the range of 10 to 50 degrees, preferably an angle in the range of 20 to 30 degrees. In the present embodiment, the angles α and β are set to the same angle.
[0024]
FIG. 2 is a schematic cross-sectional view showing a comparative example of the filter arrangement.
FIG. 2A shows a conventional filter arrangement as a comparative example. The airflow passage surfaces 11 and 12 of each high-performance filter 1 are orthogonal to the airflow directions of the airflows A and B.
The found area of the airflow passage surfaces 11, 12 viewed from the upstream flow path and the downstream flow path in the airflow direction or in the opposite direction shows the maximum value. Assuming that the wind speed distribution in the flow path of the airflow A is uniform, the width × height of the airflow passage surfaces 11, 12 is set to 600 mm × 600 mm, and the processing air volume is 200 m. ³ / Min, this filter arrangement requires four high-performance filters 1 to regulate the surface wind speed to 2.5 m / s or less, and the width W of the filter unit 2 is designed to be at least 2400 mm. I have to do it.
[0025]
FIG. 2B shows a comparative example in which the airflow passage surfaces 11 and 12 of each high-performance filter 1 are arranged in parallel to the airflow directions of the airflows A and B. The high-performance filters 1 are separated from each other at a predetermined interval. A flow path closing plate 38 orthogonal to the air flow direction of the air flows A and B interconnects the upstream ends and downstream ends of the high performance filter 1, and the flow path closing plate 39 connects the upstream end of the casing 21 and the high performance filter 1. Connect the ends. The air flow A flows into the upstream open space 5, collides with the flow path closing plates 38 and 39, largely turns the air flow direction, passes through the filter media of the high-performance filters 1 on both sides, and flows into the downstream open space 6. I do. The airflow that has flowed into the open space 6 turns the airflow direction by 90 degrees in the open space 6 and flows out to the downstream flow path. In the open spaces 5 and 6, a turbulent state or a stagnant state of the airflow A occurs, and a relatively large pressure loss occurs. Therefore, the open spaces 5 and 6 require a width approximately equal to the width of each high-performance filter 1. . For this reason, the filter unit using the filter arrangement shown in FIG. 2B has to be eventually designed to have the same width W as the filter unit shown in FIG. 2A.
[0026]
On the other hand, in the filter unit 2 of the present invention shown in FIG. 1, the open spaces 3 and 4 in which the cross-sectional area of the flow path converges or expands in the airflow direction are formed by turning, turbulence or stagnation of the airflow accompanied by a large pressure loss. A state is not generated, and the surface wind speed distribution of the air flow passage surfaces 11 and 12 is not largely unevenly distributed.
[0027]
As shown in FIG. 1, in the filter unit 2 of the present embodiment including four high-performance filters 1, the width × height = 600 mm × 600 mm of the airflow passage surfaces 11 and 12, and the processing air volume = 200 m ³ / Min, and even if the width W is set to about 600 mm, theoretically, the surface wind speed of each high-performance filter 1 can be regulated to 2.5 m / s or less. Preferably, two filter units 2 are arranged in parallel, and the processing air volume of each filter unit 2 is set to 100 m. ³ It is desirable to set the pressure to about / min in order to suppress an increase in pressure loss and secure a desired collection efficiency. Also in this case, the total width of the filter units 2 arranged in parallel is about 1200 mm, which is half that of the conventional dimensions (about 2400 mm).
[0028]
【Example】
FIG. 3 is a front view, a side view, and a rear view showing the structure of a four-sheet type filter unit according to a preferred embodiment of the present invention, and FIG. 4 is a cross-sectional view showing a method of attaching a high-performance filter to the filter unit. It is a front view and a partial enlarged sectional view.
[0029]
The filter unit 2 shown in FIGS. 3 and 4 has a configuration in which four high-performance filters 1 are accommodated in a zigzag arrangement or a bellows arrangement. Each high-performance filter 1 is composed of a general-purpose HEPA filter, and has a general standard width, height and thickness, that is, 610 mm, 610 mm, and a width, height and thickness of 60 to 70 mm. The casing 21 of the filter unit 2 has dimensions of width W ≒ 620 mm, height 高 620 mm, and depth D ≒ 630 mm, and the outer shape of the filter unit 2 is substantially a regular hexahedron. The inclination angle α / 2 (= β / 2) of each high-performance filter 1 with respect to the airflow direction is set in a range of 10 to 15 degrees, for example, 13 or 14 degrees.
[0030]
The casing 2 includes left and right side walls 22, a top plate 23, and a bottom plate 24, and square flange portions 27, 28 are attached to the opening edges of the upstream end opening 25 and the downstream end opening 26. As shown in FIG. 3 (A), the small opening surface of the rectangular frame 18 of each high-performance filter 1 is exposed and the upstream open space 3 is opened in the upstream end opening 25 that opens so as to face the airflow A. I do. A bar material 15a and a sealing material 15b (FIG. 4E) constituting the hermetic connecting portion 15 extend vertically at the center of the opening 25. The upper end and the lower end of the bar 15a are fixed to the top plate 23 and the bottom plate 24. As shown in FIG. 3C, a downstream open space 4 opens in the downstream end opening 26 that opens toward the downstream flow path. A pair of metal plates constituting the hermetic connecting portion 16 extend vertically. The upper and lower ends of the metal plate are fixed to the top plate 23 and the bottom plate 24. The center of the metal plate is slightly bent so as to make surface contact with the fore-edge surface of the rectangular frame 18.
[0031]
As shown in FIG. 4, a guide mechanism 40 and a filter holding mechanism 50 for positioning and fixing each high-performance filter 1 at a predetermined position are provided in the casing 2.
The guide mechanism 40 includes a pair of upper and lower guide members 41 extending in the direction of the inclination angle α / 2 (= β / 2), and the horizontal legs 42 of the respective guide members 41 are, as shown in FIG. The vertical strip 43 of each guide member 41 is fixed to the top plate 23 and the bottom plate 24 and rises or hangs down from the leg 42. The downstream end portions of the respective guide members 41 are close to each other and continue to the metal plate of the hermetic connection portion 16 as shown in FIG. As shown in FIG. 4A, when the high-performance filter 1 is inserted from the upstream opening 25 along the guide member 41, the high-performance filter 1 slides under the guidance of the guide member 41, and moves downstream of the square frame 18. The fore-edge surface comes into surface contact with the airtight connection portion 16. The direction and the horizontal position of the high-performance filter 1 are regulated by the guide member 41, and are positioned in the direction of the inclination angle α / 2 (= β / 2).
[0032]
The filter holding mechanisms 50 are respectively arranged between the paired guide members 41.
The holding mechanism 50 includes a rod portion 51 extending in the direction of the center line C1 (FIG. 1), a screw 52 that can be relatively displaced with respect to the rod portion 51, and a pair of left and right filter presses that are pushed out on both sides by screwing the screw 52. A portion 53 and a pair of guide rollers 54 that can abut on the downstream end of the frame 18 are provided. The guide roller 54 cooperates with the vertical band portion 43 of the guide member 41 to hold the downstream end of the high-performance filter 1 at a predetermined position. Is pressed toward the vertical band portion 43 to fix the upstream end of the high-performance filter 1 at a predetermined position.
[0033]
Thus, by the positioning action of the guide mechanism 40 and the holding action of the holding mechanism 50, each high-performance filter 1 is fixed at a predetermined position in the casing 21, and the frame 18 of the high-performance filter 1 is closed by the airtight connecting parts 15, 16. , 17 and the guide member 41 are in line contact or surface contact.
[0034]
FIG. 5 is a cross-sectional view, a front view, a rear view, and a side view showing the structure of the two-sheet type filter unit.
The filter unit 2 shown in FIGS. 3 and 4 has a configuration in which four high-performance filters 1 are housed, whereas the filter unit 2 ′ shown in FIG. I do. The structure of the filter unit 2 ′ corresponds to the configuration of a half part of the filter unit 2 described above. The width W ′ of the casing 21 ′ is set to a size of about 300 mm, and the inclination angle α / 2 (= β / 2) of the high-performance filter 1 is set within an angle range of 10 to 30 degrees. Each part of the filter unit 2 ′ has substantially the same structure as the above-described filter unit 2.
[0035]
FIG. 6 is a plan view, a side view, and a rear view showing the entire configuration of a filtering device containing the filter units 2 and 2 ′ having such a configuration.
The filtering device 70 is manufactured as a self-supporting device that can be arranged in an air-conditioning machine room or an exhaust treatment room of a building, and has an in-machine space that can accommodate the filter units 2 and 2 ′. The metal housing 71 of the filtering device 70 is composed of an assembly of left and right side wall panels 74, a top panel 75 and a bottom panel 76, and an inspection door 72 for in-machine inspection and an in-machine lighting device 73 are disposed at appropriate positions on the side wall panel 74. Is done. Both ends of the housing 71 are open, and air-conditioning equipment or air-conditioning ducts (shown by phantom lines) are connected to the upstream and downstream outer edges 77 and 78, respectively.
[0036]
The filter units 2 and 2 ′ are housed inside the filtering device 70 as shown in FIG. In the filtering device 70 shown in FIG. 6, the filter units 2 in three stages and two rows and the filter units 2 ′ in three stages and one row are arranged and arranged in the filtering device 70.
If the width w of the internal space of the filtration device 70 can be designed to be substantially a multiple of the width W of the filter unit 2, only the filter unit 2 may be housed in the filtration device 70.
[0037]
The filter units 2 and 2 ′ are arranged such that the upstream open space 3 faces the upstream airflow A, and receives the airflow A into the open space 3 and transfers the downstream airflow B from the downstream open space 4 as described above. leak. The hermetic treatment of the joint between the filter units 2 and 2 ′ and the hermetic treatment between the filter units 2 and 2 ′ and the housing 71 are performed according to a known hermetic treatment method.
[0038]
The width w of the filtering device 70 accommodating the filter units 2 and 2 'is the same as that of the related art in which each high-performance filter 1 is accommodated in a state of being arranged so as to be orthogonal to the airflow direction as shown in FIG. It is reduced to about 1/2 to 1/4 compared to the filtration device. For this reason, the space in which other building equipment and the like can be arranged can be greatly expanded, or the surface wind speed of each high-performance filter 1 is reduced, and the life or replacement time of the high-performance filter 1 is lengthened. be able to.
[0039]
Since the height h of the filtering device 70 is equivalent to that of the conventional filtering device, the height dimension does not increase. Further, since the high-performance filter 1 is inclined with respect to the directions of the air flows A: B, the depth dimension d of the filtering device 70 is slightly increased as compared with the conventional filtering device. However, since the depth dimension d coincides with the continuous direction of the air-conditioning duct or the air-conditioning equipment, as will be apparent to those skilled in the art, a slight increase in the depth dimension d is due to design considerations such as equipment layout usually performed by those skilled in the art. Can be overcome or eliminated relatively easily.
[0040]
The inventor performed a leak test using the filter unit 2 shown in FIGS. FIG. 7 shows the results of the leak test.
The leak test was carried out by interposing a test filter unit in a blow duct connected to the blower and changing the blow rate and pressure of the blower stepwise. The test filter unit has a structure in which a high-performance filter 1 in which the airflow passage surface 11 is blocked impermeable by a blind plate is attached to the filter unit 2, and substantially the total air volume passing through the test filter unit is: It can be considered that it corresponds to the amount of leak air from the filter unit 2.
[0041]
As a result of measuring the leak air flow (leak air flow) of the test filter unit, a leak rate (air flow%) value of 0.0001 or less was obtained at a blowing pressure of 400 Pa as shown in FIG. This means that in the filter unit 2, the amount of air flowing through the connection portion of the high-performance filter 1 and the gap around the outer periphery, that is, the amount of leaked air, is very small.
[0042]
FIG. 8 is a table showing the DOP test results of the filter unit 2.
As a result of performing the DOP test of the filter unit 2, as shown in FIG. 8, the filter unit 2 exhibited a performance that passed a predetermined standard (P <0.03% or E> 99.97%) of the HEPA filter. Each measurement result in FIG. 8 is a measurement result by a particle counter, and the leakage rate P and the efficiency E are respectively: leakage rate P = upstream-side fine particle concentration / downstream-side fine particle concentration × 100%; and efficiency E = 100−P. (%).
[0043]
9 to 12 are a plan view and a perspective view illustrating the details of the structure of various filter holding mechanisms. FIG. 9 shows the filter holding mechanism 50 shown in FIG. The filter holding mechanism 50 has a flat plate-shaped rod portion 51 disposed at the center of the left and right high-performance filters 1. Slots 66 and 67 extending in the longitudinal direction are formed in the rod portion 51. Vertical support shafts 61 and 63 erected on the bottom plate 24 pass through the slots 66 and 67. The rod portion 51 is engaged with the support shafts 61 and 63 so as to be displaceable in the axial direction.
[0044]
The pair of guide rollers 54 disposed at the downstream end of the rod 51 freely rotate about a vertical shaft 54a. Each roller 54 comes into rolling contact with the frame 18 of the filter 1, guides the downstream end of the filter 1 to a predetermined position, and cooperates with the vertical band 43 of the guide member 41 to filter the filter. The position of 1 is regulated. A pantograph mechanism 55 is provided at an upstream end of the rod portion 51. The pantograph mechanism 55 is constituted by a plurality of link members and a pivot portion, and is configured to press the filter pressing portion 53 against the frame 18 (FIG. 4) of the filter 1. The pressing member 53 is formed of a roller or a pressing plate that can contact the frame plate 18. The filter holding mechanism 50 shown in FIG. 9 includes a roller-type pressing member 53 on one side and a plate-like pressing member 53 on the opposite side.
[0045]
FIG. 10A illustrates a pantograph mechanism 55 having a plate-shaped pressing member 53 on both sides, and FIG. 10B illustrates a pantograph mechanism 55 having a roller-type pressing member 53 on both sides. I have. The bracket 56 is fixed to the rod part 51, and the bracket 57 is fixed to the movable part 59 of the pantograph mechanism 55. The bracket 60 is fixed to the bottom plate 24, and the rod portion 51 passes through an opening of the bracket 60.
[0046]
As shown in FIG. 9, the brackets 56 and 57 are separated from each other in the axial direction of the rod portion 51 by a distance X2, and the brackets 56 and 60 are separated from each other in the axial direction of the rod portion 51 by a distance X1. A screw 52 having an external screw passes through the brackets 56, 57, 60. The screw 52 of the present example is composed of a head-all screw bolt, and a plurality of nuts 58 are screwed to the screw 52. The bolt head and the nut 58 firmly clamp the bracket 60, and the screw 52 is fixed to the bottom plate 24 via the bracket 60. The two upstream nuts 58 abut against the brackets 56 and 57, respectively, and regulate the positions of the brackets 56 and 57. The distance X1 can be variably set by rotating the nut 58 abutting on the bracket 56 and adjusting the position of the nut 58. The distance X2 can be reduced by rotating the nut 58 in contact with the bracket 57 and adjusting the position of the nut 58. By adjusting the distance X1, the axial position of the rod portion 51 can be set, and the rod portion 51 can be positioned at the optimum position. By reducing the distance X2, the movable part 59 can be displaced, and the pantograph mechanism 55 can be expanded. Due to the expansion of the pantograph mechanism 55, the left and right pressing members 53 press the frame 18 of the high-performance filter 1 against the vertical strip 43 of the guide member 41, and the filter 1 is fixed at a predetermined position.
[0047]
FIG. 11 is a plan view and a perspective view showing a modification of the filter holding mechanism.
The filter holding mechanism 50 shown in FIG. 11 includes a support shaft 68 fixed to the rod portion 51, and a swing lever 69 rotatably supported by the support shaft 68. The roller type pressing member 53 is attached to the tip of the swing lever 69. The swing lever 69 presses the frame 18 of the high-performance filter 1 against the vertical band 43 of the guide member 41 by the right and left pressing members 53 in the expanded position shown in FIG. Secure in position. The pressing member 53 is separated from the frame 18 by the rotation of the swing lever 69 in the direction indicated by the arrow in FIG. 11B, and the filter 1 can be taken out of the casing. The swing lever 69 includes a stopper 69a that regulates the rotational movement of the lever.
[0048]
FIG. 12 is a plan view and a perspective view showing another modified example of the filter holding mechanism.
The filter holding mechanism 70 shown in FIG. 12 is composed of a jig which can be inserted between the high-performance filters 1 and, as shown in FIG. 12 (B), includes upper and lower filter pressing plates 71, 72 and pressing plates 71, 72. Vertical struts 73 and 74 are provided for connection. The pressing plates 71 and 72 have a planar shape of an isosceles triangle, and include left and right edges parallel to the guide member 41. A pair of upper and lower screw insertion holes 75 is formed in the support column 74 that interconnects the apexes of the pressing plates 71 and 72. As shown in FIG. 12A, the female screw portion 77 is fixed to the airtight connecting portion 16, and the male screw 76 inserted into the insertion hole 75 is screwed into the female screw portion 77. By the tightening of the male screw 76, the filter holding mechanism 70 moves to the downstream side as a whole, and the side edges of the pressing plates 71 and 72 move the frame 18 of the high-performance filter 1 to the vertical band portion 43 of the guide member 41. To fix the filter 1 at a predetermined position.
If desired, pressing means 78 such as rollers or protrusions are provided on the side edges of the pressing plates 71,72. Thus, the filter holding mechanism 70 is inserted between the filters 1 in a wedge manner, and fixes the filter 1 in a predetermined position by tightening the male screw 76, and allows the filter 1 to be removed by releasing the male screw 76. .
[0049]
As described above, the preferred embodiments of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and various modifications or changes may be made within the scope of the invention described in the claims. Obviously, such modifications and variations are also included in the scope of the present invention.
[0050]
For example, the filter unit may be designed to have a structure in which three high-performance filters or five or more high-performance filters can be installed.
Further, the present invention is not limited to a filter unit for a HEPA filter, a UPLA filter, a chemical filter, or a filter for removing salt damage. It can be applied preferably, and this will exhibit advantages such as a smaller filter unit or a longer filter replacement cycle.
[0051]
Further, as the structure of the filter holding mechanism, another structure such as a latch type or a spring type holding mechanism may be applied.
[0052]
【The invention's effect】
As described above, according to the above configuration of the present invention, it is possible to provide a small-sized filter unit that accommodates a high-performance filter such as a HEPA filter in a compact manner and enables efficient use of the building equipment space.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view and a perspective view showing a filter arrangement according to a preferred embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view showing a comparative example of a filter arrangement.
FIG. 3 is a front view, a side view, and a rear view showing a structure of a four-sheet interior filter unit according to a preferred embodiment of the present invention.
4A and 4B are a cross-sectional view and a partially enlarged cross-sectional view showing a method of attaching a high-performance filter to the filter unit shown in FIG.
FIG. 5 is a cross-sectional view, a front view, a rear view, and a side view showing the structure of a two-sheet type filter unit according to another embodiment of the present invention.
FIG. 6 is a plan view, a side view, and a rear view showing an entire configuration of a filtration device containing the four-sheet type and two-sheet type filter units shown in FIGS.
FIG. 7 is a table showing the results of a leak test performed using the filter units shown in FIGS. 3 and 4.
FIG. 8 is a table showing DOP test results of the filter units shown in FIGS. 3 and 4.
FIG. 9 is a plan view illustrating the details of the structure of the filter holding mechanism shown in FIG. 4;
FIG. 10 is a perspective view of the filter holding mechanism shown in FIG.
FIG. 11 is a plan view and a perspective view showing a modification of the filter holding mechanism.
FIG. 12 is a plan view and a perspective view showing another modified example of the filter holding mechanism.
[Explanation of symbols]
1 high-performance filter
2, 2 'filter unit
3 Upstream open space
4 Downstream open space
11, 12 Air flow passage surface
15, 16, 17 airtight joint
21 Casing
40 Guide mechanism
50 Filter holding mechanism
A upstream airflow
B Downstream airflow

Claims (8)

In a filter unit having a high-performance filter and a casing that can accommodate the filter,
Positioning means for positioning the plurality of high-performance filters in a direction in which the airflow passage surface is inclined at a predetermined angle (α / 2) with respect to the airflow direction; and holding means for holding the positions of the high-performance filters. Have
An upstream open space in which the flow path cross section expands and converges in the airflow direction in the airflow direction is formed between the high-performance filters or between the high-performance filter and the inner wall surface of the casing, A downstream open space in which the flow path section expands in the airflow direction and converges in the direction opposite to the airflow direction is formed between the high-performance filters or between the high-performance filters and the inner wall surface of the casing. A filter unit characterized in that: The filter unit according to claim 1, wherein the inclination angle (α / 2) is set within an angle range of 5 to 25 degrees. The inclination angle (α / 2) is such that at least 3 × n sheets of the high-performance filters are accommodated in a casing capable of accommodating a predetermined number n of the high-performance filters in a state where the airflow passage surface is arranged in a direction orthogonal to the airflow direction. The filter unit according to claim 1, wherein the filter unit is set at an angle capable of accommodating the filter. The joint between the high-performance filters or the joint between the high-performance filter and the inner wall surface of the casing is subjected to an airtight treatment by an airtight means. The filter unit according to the item. The convergence angle (α) of the upstream open space and the convergence angle (β) of the downstream open space are set to substantially the same angle value. The filter unit according to the item. The positioning unit has a guide member that regulates an inclination angle and a position of the high-performance filter, and the holding unit contacts the frame of the high-performance filter and holds the frame on the guide member. The filter unit according to claim 1, further comprising a contact portion. The filter unit according to claim 6, wherein the holding unit further includes a pressing portion that presses the frame body against the guide member. A filter device comprising the filter unit according to any one of claims 1 to 7, wherein the filter units are arranged vertically and horizontally so that an upstream opening of each filter unit faces an upstream airflow. A filtering device, characterized in that:

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