SE2151471A1

SE2151471A1 - Filter assembly

Info

Publication number: SE2151471A1
Application number: SE2151471A
Authority: SE
Inventors: Samu Pöri; Tommi Lustig
Original assignee: Leanfil Oy
Priority date: 2019-05-03
Filing date: 2020-04-30
Publication date: 2021-12-02
Also published as: SE545881C2; FI12708Y1; DE112020002239T5; FI12708U1; WO2020225477A1; FI129956B; FI20195361A1

Abstract

of the DisclosureThe invention concerns a filter assembly (16), comprising a frame having a top and a bottom side. The frame (6) defines an aperture in which a bag -like insert of a filter material may be inserted. A first tape (9) of a fastener is attached to the outer side of the frame and running around the perimeter of the frame and a second tape (13) of a fastener attached to an upper portion of the insert. The insert is arranged to fit into the frame with its open upper portion bent over the frame to cover the top side of the frame and to mate the first and second fastener tapes with each other at an outer edge of the frame, to form a sealed joint when said tapes are fully engaged with each other.

Description

TITLE OF THE INVENTION Filter Assembly FIELD OF THE INVENTION The present invention relates to air filters used in buildings. More specifically, the inventionrelates to cartridge type filters having a frame with a bag- like filter cloth arranged within the frame, which may be used as a unit to be inserted transversely in an air duct or the like.BACKGROUND OF THE INVENTION Fans or blowers are used along with ductwork to circulate air through a room or area of abuilding. The blower typically draws air from within the room through a retum air duct and thenforces the air back into the room through a supply air duct. To heat or cool the air, the blower may also force or draw the air across a heat exchanger.

To prevent dust from accumulating on various equipment, and on the ductwork downstream ofthe blower in the retum air duct, filters may be installed adj acent to the blower. Filters create apressure drop that reduces the amount of airﬂow. To minimize the pressure drop, the cross-sectional area of the filter is usually increased by adding pleats to the filter cloth, installing thefilter at an angle relative to the duct, or by forming the filter as an elongated bag that extends lengthwise into an air duct.

All filters must be cleaned or changed from time to time according to the maintenance cycle ofthe building. Used air duct filters, such as cartridge filters, are usually discarded and replaced bynew ones. Depending on the number of ducts and the blowers and their size, the number ofreplacement cartridges in one maintenance cycle may vary from one to hundreds. A typical filterusually consists of a durable metal or plastic frame, with interrnediate bars that form slots in onedirection across the frame. In these slots, filter cloth bags are fastened between the interrnediate bars or otherwise, in a pleated fashion.

When a cartridge filter is discarded, also the metallic (or plastic) frame is thrown away. This, ofcourse, is a waste of resources. Individual filter bags are usually not intended to be removablefrom the frames, and are attached to the frames by any means from undemeath. Thus the framesget dirty from the dust, debris and fatty substances (e.g. in a kitchen) that ﬂows into a retum duct, and they would need to be removed anyway.

There is thus a need for improvements in such maintenance Work, in order to find a solution tothe ﬁlter Waste problem and to reduce the amount of Work needed While performing filter changes.

The present invention aims to solve or alleviate these problems to a great extent. The invention is characterized by What is stated in the appended claims.According to an aspect of the invention, a filter assembly is provided, that comprises: - a frame having a top and a bottom side and inner and outer edges, said inner edges ofsaid frame defining an aperture, - a bag -like insert of a filter material having an open upper portion and at least one closedbottom portion, - a first tape of a fastener attached to the outer edge of said frame and running around theouter perimeter of the frame; - a second tape of a fastener attached to said upper portion of said insert.

The insert is arranged to fit into the aperture of said frame With the open upper portion bent overthe frame to at least partly cover the top side of the frame. The first second tape is mated Withthe first fastener tape to form a sealed joint at the outer edge of the frame When the tapes are fully engaged With each other.

The structural element "tape" is here used to describe any elongate fastener aimed to form asealed joint between two separate mating parts of a fastener. The Word tape is thus meant to beunderstood broadly, as an attachable carrier of a fastener, or as an integral part of the fasteneritself. A number of such exemplary tapes are disclosed, but it is clear to one skilled in the artthat any elongate fastener may be used in a manner claimed, Without departing from the scope of the invention.

In some embodiments, the frame is provided With parallel interrnediate bars across said aperturethat defines slots across the aperture. The insert may then have multiple bags formed in a pleatedfashion having a shared open upper portion and separate closed bottom portions. Each bag may then be arranged to fit into one corresponding slot.

In some other embodiments, the frame may be provided With a grid of interrnediate bars across the aperture defining a number of slots. In such cases, the insert may be formed With multiple bags having, for example, pointed and closed bottom portions and a shared open upper portion.Each bag Would then be designed to fit into one slot. A honeycomb-like structure of the grid may also be envisaged.

In some embodiments, the first tape is a first half of a zip fastener and the second tape is asecond half of a zip fastener. The insert is arranged to fit into the frame With its open upperportion bent over the frame to at least partly cover the top side of the frame. The first and secondzip fastener halves may be mated With each other to form a sealable zip fastener When pulling aslider provided in either one of said first or second zip fastener halves. An insert pin on eitherone of the first and second zip fastener halves is inserted to a slider in the opposite zip fastener half, in order to form the sealable zip fastener.

According to some embodiments, the first tape is a first half of a hook-and-loop fastener and saidsecond tape is a second half of hook-and-loop fastener. When the insert is arranged into theframe With the open upper portion bent over the frame, the second tape Will overlap the first tape to form a sealed joint When pressing said second tape to said first tape.

According to some embodiments, frame has the shape of a rectangle or a square, but of coursealso other shapes are possible, such as a circle. The frame is preferably made of a rigid material,such as Wood, metal or a polymer material. HoWever, flexible materials may also come into use, if the rigidity needed to retain the filter assembly in place is provided by other means.

In some embodiments, the interrnediate bars across the aperture defining said slots are barsattached to the frame by any means of fastening, such as nailing, gluing, Welding, or by any formof clip means, for example. Altematively, the frame and the interrnediate bars may be integral With and formed of the same material as the frame in one manufacturing process.

The invention offers considerable advantages. Apart from the obvious one of providing re-usablefilter assembly frames, the frames are also always clean as at least the upper side of the frame is always covered by the filter material.

Filter assemblies Where the frame is made of Wood may be disposed of in environmentallyfriendly Ways by recycling, or they may be bumed. Frames made of other materials may also be easily recycled, as the filter insert is removable.

No fastening of individual filter bags is needed, the Who le filter insert is just dropped on top of the frame and secured With a zipper.

BRIEF DESCRIPTION OF THE DRAWINGSFig. l shows a ﬁlter assembly according to prior art; Fig. 2 shows an exemplary frame of a filter assembly according to one embodiment of the invention; Fig. 3 shows an exemplary insert of a filter assembly according to one embodiment of the invention; Fig. 4 shows a first step of forrning an inVentiVe filter assembly according to one embodiment of the inVention; Fig. 5 shows a second step of forrning an inventive filter assembly according to one embodiment of the inVention; and Fig. 6 shows a ready filter assembly according to one embodiment of the inVention; Fig. 7 shows a ready filter assembly according to another embodiment of the inVention; Fig. 8 shows the frame of a filter assembly according to a further embodiment of the invention.DETAILED DESCRIPTION OF EMBODIMENTS In Fig. l is shown a filter assembly l according to prior art with a frame 2, interrnediate bars 4and with one filter bag 3 attached 5 between each slot formed by the interrnediate bars 4, or atthe edges, by an interrnediate bar 4 and the frame 2. The air flow direction is from the upper ortop side of the frame 2 downwards to the bags and the filtered air exits the filter through thebottoms of the bags 3.

In Fig. 2 is shown a square-shaped frame 6 of a filter assembly according to the presentinvention. The frame 6 has a top side 7a, outer edges 7b, inner edges 7c and a bottom side 7d(not shown). The inner edges 7c defines an aperture having interrnediate bars 8 across theaperture, which in tum defines three slots A, B and C. Obviously, depending on the size,circumstances and requirements of the filter assembly, the number of slots is a design criteriaand may Vary from l to any number upwards. Also shown is a ﬁrst half 9 of a zip fastener withits tape attached to the outer side 7b of the frame 6 and running around the perimeter of the frame. The zip fastener half 9 is in this exemplary embodiment is provided with a slider l0.

In Fig. 3 is shown a bag -like insert 11 of a filter material. The insert has an open upper portion14 shared by multiple bags forrned in a pleated fashion, in this case the three bags 12. A secondhalf 13 of a zip with its tape is attached to and encircling the upper portion 14 of the insert. Thematerial of the insert will depend on the application and may thus be made of a variety of materials, such as paper, cotton, polyester, etc.

An insert according to Fig. 3 may be arranged to fit into the aperture of the frame according toFig. 2 in a way that its open upper portion when bent over the frame will cover all of the top side7a of the frame. The second tape is mated with the first fastener tape to form a sealed joint at the outer edge 7b of the frame when the tapes are fully engaged with each other.

In Fig. 4 is shown a first step of forrning the inventive filter assembly. An insert 11 as shown inFig. 3 is dropped in the direction of the arrow through a frame 6. In this example, each bag 12 ofthe insert 11 will occupy one of the slots A - C of Fig. 2.

In Fig. 5 is shown a second step of forrning the inventive filter assembly, where the insert 11 isbeing ﬁtted in a frame 6 with an edge of the insert upper portion 14 bent over the frame 6 tocompletely cover the top side 7a of the frame in fig. 2, all the way down to the outer edge 7b ofthe frame until the zipper. The first and second zip fastener halves 9, 13 are mated with eachother in an ordinary fashion to form a closable zip fastener when pulling the slider 10, which may be provided in either one of the first or second zip fastener halves.

Obviously, the mating of the first and second zip fastener halves 9, 13 with each other may beeffected by an insert pin 15 on either one of the zip fastener halves, that is then inserted to the slider 10 in the opposite zip fastener half In Fig. 6 is shown a completed inventive filter assembly 16, where the slider 10 has been pulledaround the upper portion 14 of the insert 11, thus closing the zipper formed by the first andsecond halves 9, 13. As can be seen, the top of the frame 6 and interrnediate bars 8 are now covered by the insert 11.

In Fig. 7 is shown filter assembly 17 with an insert 20 according to another embodiment of theinvention. Here a first tape 18 is a first half of a hook-and-loop fastener, i.e. a Velcro® fastener,and a second tape 19 is a second half of a Velcro® fastener. In a similar fashion as shown inFigs. 2 to 6, the insert 20 is arranged to fit into a frame with an open upper portion bent over the frame to cover the top side of the frame. The hook-and-loop tape halves will then overlap each other at the outer side of the frame to form a sealed joint When pressing the second tape 19 to the first tape 18.

In Fig. 8 is shown a square-shaped frame 24 of a filter assembly according to anotherembodiment of the invention. The frame 24 has a top side 21 and interrnediate bars 22 and 23def1ning a grid across the aperture of the frame. The grid def1nes a number of slots 25 (here nineslots). An insert (not shoWn) formed With multiple bags and having a shared open upper portionand separate closed bottom portions may then be inserted in the frame 24 With one bag iin each ofthe slots 25.

It is to be understood that the embodiments of the invention disclosed are not limited to theparticular structures, process steps, or materials disclosed herein, but are extended to equivalentsthereof as Would be recognized by those ordinarily skilled in the relevant arts. It should also beunderstood that terrninology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting.

Reference throughout this specification to one embodiment or an embodiment means that aparticular feature, structure, or characteristic described in connection With the embodiment isincluded in at least one embodiment of the present invention. Thus, appearances of the phrases"in one embodiment" or "in an embodiment" in various places throughout this specification arenot necessarily all referring to the same embodiment. Where reference is made to a numericalvalue using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

As used herein, a plurality of items, structural elements, compositional elements, and/ormaterials may be presented in a common list for convenience. However, these lists should beconstrued as though each member of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as a de facto equivalent ofany other member of the same list solely based on their presentation in a common group Withoutindications to the contrary. In addition, various embodiments and example of the presentinvention may be referred to herein along With altematives for the various components thereof. Itis understood that such embodiments, examples, and altematives are not to be construed as defacto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention.

Furthermore, the described features, Structures, or Characteristics may be combined in anysuitable manner in one or more embodiments. In the description, numerous specific details areprovided, such as examples of frames, slots, fasteners, shapes, etc., to provide a thoroughunderstanding of embodiments of the invention. One skilled in the relevant art will recognize,however, that the invention can be practiced without one or more of the specific details, or withother methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

While the forgoing examples are illustrative of the principles of the present invention in one ormore particular applications, it will be apparent to those of ordinary skill in the art that numerousmodifications in form, usage and details of implementation can be made without the exercise ofinventive faculty, and without departing from the principles and concepts of the invention.Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

The verbs "to comprise" and "to include" are used in this document as open limitations thatneither exclude nor require the existence of also un-recited features. The features recited independing claims are mutually freely combinable unless otherwise explicitly stated.Furthermore, it is to be understood that the use of "a" or "an", that is, a singular form, throughout this document does not exclude a plurality.INDUSTRIAL APPLICABILITY At least some embodiments of the present invention find industrial application in the field of filters.

Claims

1. A filter assembly (16), comprising: a frame (6) having a top and a bottom side (7a, 7d) and inner and outer edges (7c, 7b), said inner edges (7c) of said frame defining an aperture, - a bag -like insert (11) of a filter material having an open upper portion (14) and at least one closed bottom portion, - a first tape (9) of a fastener attached to the outer edge of said frame and running around the outer edge (7b) of the frame; - a second tape (13) of a fastener attached to said upper portion (14) of said insert (11); and Wherein said insert (11) is arranged to fit into the aperture of said frame (6) With said open upper portion(14) bent over said frame to at least partly cover the top side (7a) of the frame and to mate saidsecond fastener tape (13) With said first fastener tape (9) to form a sealed joint at said outer edge (7d) of the frame (6) When said tapes are ﬁilly engaged With each other.

2. A filter assembly according to claim 1, Wherein said frame (6) is provided With parallelinterrnediate bars (8) across said aperture defining slots (A, B, C) across said aperture, andWherein said insert (11) has multiple bags (12) formed in a pleated fashion having a shared openupper portion (14) and separate closed bottom portions, and Wherein each bag (12) is arranged to fit into one slot (A, B, C).

3. A filter assembly according to claim 1, Wherein said frame (6) is provided With a grid ofinterrnediate bars (22, 23) across said aperture defining a number of slots (25), and Wherein saidinsert (11) is formed as multiple bags having a shared open upper portion (14) and separate closed bottom portions, and Wherein each bag is arranged to fit into one slot (25).

4. A filter assembly according to any of claims 1 - 3, Wherein said first tape (9) is a first half of azip fastener and said second tape (13) is a second half of a zip fastener, and Wherein said insert isarranged to fit into said frame (6) With said open upper portion (14) bent over said frame to at least partly cover the top side of the frame and to mate said first and second zip fastener halves (9, 13) With each other to form a sealable zip fastener When pulling a slider (10) provided in either one of said first or second zip fastener halves.

5. A filter assembly according to claim 4, Wherein the mating of said first and second zip fastenerhalves (9, 13) With each other to forrn a sealable zip fastener is effected by an insert pin (15) oneither one of the first and second zip fastener halves that is inserted to a slider in the opposite zip fastener half

6. A filter assembly according to any of claims 1 - 3, Wherein said first tape (18) is a first half ofa hook-and-loop fastener and said second tape (19) is a second half of a hook-and-loop fastener,and Wherein said insert (20) is arranged to fit into said frame With said open upper portion bentover said frame to cover the top side of the frame and to overlap said first tape With said second tape to form a sealed joint When pressing said second tape (19) to said first tape (18).

7. A filter assembly according to any of claims 1 - 6, Wherein said frame (6) has the shape of a rectangle or a square.

8. A filter assembly according to any of claims 1 - 7, Wherein said frame (6) is made of a rigid material selected any one of the folloWing: Wood, metal or a polymer material.

9. A filter assembly according to any of claims 2 - 8, Wherein said interrnediate bars (8; 22, 23) across said aperture are bars attached to the frame (6) by any means of fastening.

10. A filter assembly according to any of claims 2 - 8, Wherein said frame and said interrnediatebars (8; 22, 23) across said aperture are integral With and formed of the same material as said frame (6) in one manufacturing process.