Air filter and filter unit for air filter

Abstract

The present invention relates to an air filter comprising: a filter housing; a blower disposed in the filter housing and for generating an air flow from the air inlet to the air outlet; a filter unit arranged in an operating position in the filter housing between the air inlet and the air outlet, the filter unit having: a) a plurality of filter elements wherein an outer filter element and a filter element adjacent thereto are arranged at an angle to each other and are connected to each other at a joint edge; and b) a first side holder and a second side holder for securing the filter element. A first sheet made of a flexible material is secured to the outer end of the outer filter element and extends parallel to the engagement edge, the first sheet having an unattached free overhang.

Description

Technical Field

[0001] The present invention relates to an air filter having a filter housing and a filter unit arranged in the filter housing. The present invention also relates to a filter unit for such an air filter. Background Art

[0002] EP 4245999 A1 discloses an air filter having a filter housing and a filter unit. A blower is arranged in the filter housing, and the blower is used to generate an air flow from an air inlet to an air outlet. The filter unit is arranged in an operating position between the air inlet and the air outlet. The filter unit includes a plurality of plate-shaped filter elements, and two adjacent filter units form a V shape. Accordingly, the outer filter elements of the filter unit and the filter elements adjacent thereto are also arranged in a V-shaped configuration and enclose an angle of approximately 20°. These two filter elements are connected to each other at the joining edge. In order to hold the individual filter elements in the V-shaped configuration, the filter unit includes a first side holder and a second side holder spaced apart from each other. The individual filter elements extend between these side holders and are attached to the side holders.

[0003] In the air filter of EP 4425999 A1, as viewed in the direction of the air flow, the filter unit is arranged in front of the blower. To make the air filter work efficiently, it is necessary to ensure a good seal between the filter element and the filter housing. Otherwise, there is a risk that part of the air flow will pass through the filter unit through leakage and will not be filtered. Therefore, unfiltered air may enter the blower and then be released back into the environment.

[0004] Since the filter unit may become clogged with filtered particles or the like during the operation time of the air filter, it is desirable that the filter unit can be easily removed from the housing and replaced with a new or un-cleaned filter unit. However, easy replacement of the filter unit and good sealing at the same time are usually conflicting goals. In addition, if the filter unit is only a replacement part to be discarded after use, it should be simple and inexpensive. Summary of the Invention

[0005] The present invention is based on the following object: to provide an air filter that works efficiently and is easy to operate.

[0006] The object of the present invention is solved by the feature combination according to claim 1. Embodiments of the present invention can be obtained from the dependent claims of claim 1.

[0007] According to the present invention, a first sheet-like member made of a flexible material is fastened to the outer end of an external filter element. The sheet-like member extends parallel to the joining edge. The sheet-like member is not fastened over its entire width but has an unattached free overhang. In the operating position of the filter unit, the unattached free overhang abuts against a first abutment surface. The overhang is in a deformed state, and the restoring force of the flexible material presses the overhang against the first abutment surface. The fact that the overhang or the unfixed part of the sheet-like member leans against the first abutment surface with a certain force makes it easy to achieve a good and firm seal between the filter unit and the filter housing.

[0008] In one embodiment, the length of the sheet-like member is at least five times the width of the sheet-like member. The part of the sheet-like member attached to the outer end of the external filter element can be 20 to 80% of the total width of the sheet-like member.

[0009] Preferably, the flexible material is a non-woven material. Alternatively, the flexible material can be plastic or other flexible materials. The flexible material can be attached to the outer end of the external filter element, for example, by gluing. The flexibility of the overhang can be adjusted using the thickness of the sheet-like member (or non-woven fabric), the width of the overhang, and / or the choice of material used, and thus the force with which the overhang presses against the first abutment surface in a deformed state can be adjusted.

[0010] The first side retainer and the filter housing can have locking lugs and locking notches. In the locked state, the connection between the locking lugs and the locking notches holds the filter unit in the operating position. The locking lugs can be part of the first side retainer. It is also possible that the locking lugs are associated with the filter housing.

[0011] In one embodiment, the first side retainer is made of semi-flexible plastic. Preferably, polyurethane is used, which can be produced by reacting an isocyanate component with a polyol component. The first side retainer is preferably an injection molded part.

[0012] The second side retainer preferably has the same features and characteristics as the first side retainer. In one embodiment, the first side retainer and the second side retainer are mirror-symmetrical about the central axis of the filter unit.

[0013] Inside the filter housing, a frame can be provided, which has a flow cross-section that is substantially completely covered by the base of the filter unit. The frame can be rectangular. The first side edge of the frame can form the first abutment surface. The frame can be fixedly connected to the outer wall of the housing. For example, the frame can be part of a blower carrier, and the blower is fixed inside the housing through the blower carrier.

[0014] The frame may have a second side edge which is preferably perpendicular to the first side edge and forms a second abutment surface which, in the operating position of the filter unit, faces the outer surface of the first side retainer. An elongate sealing rib may be provided on the outer surface of the first side retainer which abuts against the second abutment surface and thus ensures sealing at this side edge. The sealing rib and the base body of the first side retainer are preferably formed as a single piece, which simplifies the manufacture of the first side retainer.

[0015] The sealing rib may extend over the entire length of the outer surface and form a sealing ridge at the end edge of the first side retainer which, in the operating position of the filter unit, abuts against the first abutment surface in the edge section. This edge section preferably adjoins the middle section or main section of the first side edge without a gap, in which section the (non-woven) sheet-like part abuts against the first abutment surface. The sealing ridge of the second side retainer may also abut against the first abutment surface.

[0016] To further enhance the sealing at the second side edge, the first side retainer may have a sealing lip which has a free end that abuts against the inclined part of the second abutment surface. Thus, in one embodiment, both the sealing rib and the sealing lip are in contact with the second abutment surface, thereby forming a particularly good seal. Preferably, the sealing lip extends over the entire length of the first side retainer. The sealing rib and the sealing lip may extend parallel to each other and are only spaced a small distance apart (e.g., less than 4 cm).

[0017] In one embodiment, the rectangular frame is symmetric, where the third side edge corresponds to the first side edge and the fourth side edge corresponds to the second side edge. The first side edge and the third side edge are spaced apart and extend parallel to each other. The second side edge and the fourth side edge extend transversely thereto. Preferably, the filter unit has corresponding symmetry. In particular, it has a second sheet-like part which cooperates with a third abutment surface and corresponds structurally and functionally to the first sheet-like part.

[0018] At least one guiding rib with a rear locking surface may be provided on the side wall of the filter housing, and the sheet-like part engages behind this rear locking surface when the filter unit reaches the operating position during insertion into the filter housing. The guiding rib may extend from the inner wall of the side wall towards the interior of the housing. When the filter unit is inserted, the overhang of the sheet-like part slides along the guiding rib. At the end, the guiding rib may have an inclined surface, whereby the overhang is further deformed. After passing the inclined surface, the sheet-like part then engages behind the rear locking surface.

[0019] In one embodiment, the filter insert is mainly held in the operating position by the locking connection of the locking lug and the locking notch described above.

[0020] Preferably, a plurality of guide ribs extending parallel to each other are provided. For example, each side wall may provide five to ten parallel guide ribs.

[0021] Another object of the present invention (i.e., to provide a filter unit for the above air filter) is solved by Technical Solution 11.

[0022] The filter unit according to the present invention is used in an air filter, particularly in an air filter according to Technical Solutions 1 to 10, wherein the air filter includes a filter housing and a blower disposed in the filter housing for generating an air flow in the filter housing. The filter unit according to the present invention includes a plurality of filter elements, wherein an outer filter element and an adjacent filter element are arranged in a V shape and are connected to each other at the joint edge. The filter unit further includes a first side holder and a second side holder, and the filter elements extend between the first side holder and the second side holder in the direction of the joint edge. A first sheet member made of a flexible material is attached to the outer end of the outer filter element, and the first sheet member extends parallel to the joint edge. The sheet member is not fixed over the entire width but has a free overhanging portion that is not attached. In the operating position of the filter unit in the filter housing, the overhanging portion is adapted to rest against a first abutment surface of the air filter in a deformed state, wherein the restoring force of the flexible material presses the overhanging portion sealingly against the first abutment surface.

[0023] Embodiments of the filter unit according to the present invention can be obtained from the above description of the air filter according to the present invention, which particularly describes various embodiments of the filter unit. Description of the Drawings

[0024] The present invention is explained in more detail with reference to the exemplary embodiments shown in the accompanying drawings. Shown in the drawings are:

[0025] Figure 1 An air filter is shown;

[0026] Figure 2 The air filter shown in exploded view Figure 1 ;

[0027] Figure 3 A first perspective view of the filter unit of the air filter is shown;

[0028] Figure 4 Shown Figure 3 Another perspective view of the filter unit;

[0029] Figure 5 Shown Shown Figure 1 A cross-sectional view of the air filter;

[0030] Figure 6Shows the locking connection of the locking lug and the locking notch;

[0031] Figure 7 Shows a cross-section of the first abutment surface of the filter unit; and

[0032] Figure 8 Shows a cross-section of the second abutment surface of the filter unit. Detailed implementation

[0033] Figure 1 and Figure 2 Shows an air filter, which is globally labeled 1. The air filter 1 includes a filter housing 10 and a blower 20 (see Figure 2 ), and the blower 20 is arranged at an installation position in the filter housing 10. The blower 10 generates an air flow in the filter housing 10 (see arrow 2), and this air flow enters the filter housing 10 at the air inlet 11 and leaves the filter housing 10 at the air outlet 12.

[0034] As seen in the direction of the air flow 2, the filter unit 50 is arranged in front of the blower 20. The filter unit 50 can be slid into the filter housing 10, for example, to replace a previously removed filter unit. The direction in which the filter unit 50 is pushed into the filter housing 10 corresponds to the direction of the air flow 2. The cuboid housing 10 substantially includes four side walls 13.

[0035] As Figure 5 is visible, the blower 20 is held in place inside the filter housing 10 by a blower carrier 30. The blower carrier 30 has a frame 31, and the frame 31 is attached to the side wall 13 of the filter housing 10. A funnel-shaped or frustum-shaped transition section 32 is adjacent to the frame 31, and through the transition section 32, the flow cross-section of the frame 31, which is only slightly smaller than the flow cross-section of the filter housing 10, is reduced to the flow cross-section of the inlet 21 of the blower 20.

[0036] Figure 3 and Figure 4 Shows the filter unit 50 in two perspective views. The filter unit 50 has six rectangular plate-shaped filter elements 51, and its outer filter element is denoted as 51a, and the adjacent filter element is denoted as 51b (also see Figure 5)。The other filter elements are denoted by reference numerals 51c to 51f, whereby the filter element 51f represents a further external filter element. The filter elements 51a and the adjacent filter element 51b are connected to each other at the joining edge 52 and branch off from this edge 52 at an angle of approximately 20°. Thus, the filter elements 51a, 51b are arranged in a V-shaped configuration. The remaining filter elements 51c to 51f are also arranged in this V-shaped configuration, whereby, for example, the filter element 51b forms a V-shape leading to the blower 20 or the air outlet 12 with the external filter element 51a and at the same time forms another V-shape with the filter element 51c, but now leading to the air inlet 11.

[0037] To fix the filter elements 51a to 51f, first side holders 53 and second side holders 54 spaced apart from each other are provided. The distance between the side holders 53, 54 corresponds to the length of the filter element 51, and the filter element 51 is held by the two side holders 53, 54 at the respective end faces. The groove 55 in the base body 56 of the first side holder 53 is used to fix the filter element 51 to the base body 56.

[0038] The second side holder 54 is mirror-symmetrical to the first side holder 53 and has the same structure. The components or details of the second side holder 54 are denoted by the same reference numerals as the corresponding components of the first side holder 53.

[0039] A first sheet-like part 58 made of a flexible material is attached to the outer end 57 of the external filter element 51a, and the first sheet-like part 58 extends parallel to the joining edge 52. From Figure 3 and Figure 4 it is obvious that the first sheet-like part 58 is not attached to the outer end 57 over its entire width but has a free overhanging part 59 that is not attached.

[0040] A second sheet-like part 60 is attached to the outer end 57 of the external filter element 51f, and like the first sheet-like part 58, the second sheet-like part 60 has a free non-attached overhanging part 59. From Figure 5 and Figure 7 it is clear what the function of the first sheet-like part 58 is (mutatis mutandis for the second sheet-like part). Figure 5 and Figure 7 The filter unit 30 is shown in the operating position, in which the filter unit 30 is in sealing contact with the frame 31 of the blower carrier 30. The sealing contact of the filter unit 50 against the frame 31 ensures that the air sucked in by the blower 20 does not flow unfiltered past the filter unit 50 and into the blower 20.

[0041] The first side edge 33 of the frame 31 forms a first abutment surface, against which the first sheet-like part 58 leans in the operating position of the filter unit 50 (see Figure 7)。In particular, the overhang 59 rests on this first abutment surface in a deformed state, wherein due to the deformation, the elastic restoring force presses the overhang against the first abutment surface. Thus, a seal is provided between the filter element 50 and the frame 31 along the first side edge 33.

[0042] The second side edge 34 of the frame 31 extends perpendicular to the first side edge 33 (see Figure 2 ). In order to also achieve a seal between the filter unit 50 and the frame 31 at this side edge 34, the first side retainer 53 has a sealing rib 61 on its outer surface. The sealing rib 61 extends over the entire length of the first side retainer 53 up to the two end edges 62 of the base body 56. At each end edge 62, the sealing rib 61 forms a sealing ridge 63. Additionally, a sealing lip 64 is provided, which also serves to seal at the second side edge 35. As can be clearly seen from Figure 8 (which shows a cutaway view of a cross-section transverse to this second side edge 35 and a cutaway view of the filter unit 50), in the operating position of the filter unit 50, the sealing rib 61 rests on the second side edge 34. Figure 8 The small overlap between the sealing rib 61 and the second abutment surface in is intended to clearly show that the sealing rib 61 contacts the second abutment surface in a compressed form. The sealing lip 64 (also shown in Figure 8 as having a small overlap) rests on the inclined portion 35. The free end 65 is pressed inwards (i.e., towards the opposite second side retainer 54).

[0043] The frame 31 has a third side edge 36 and a fourth side edge 37 (see Figure 1 ), whereby the third side edge 36 corresponds to the first side edge 33 and the fourth side edge 37 corresponds to the second side edge 35. In the operating position of the filter unit 50, the second sheet-like member 60 interacts with the third side edge 38, whereby the overhang 59 is also pressed against the third side edge. As shown for the second side edge 34 in Figure 8 , the fourth side edge interacts with the corresponding sealing rib 61 and sealing lip 64 of the second side retainer 54. Thus, the sheet-like members 58, 60 and the sealing ribs 61 and sealing lips 64 of the two side retainers 53, 54 form a circumferential seal between the frame 31 and the filter unit 50.

[0044] In order to hold the filter unit 50 in the operating position and press it against the frame 31 with a certain force, the first side retainer 53 (and correspondingly, the second side retainer 54) has locking lugs 66 on each end edge 62, which form a locking connection with the corresponding locking notches 14 of the housing 10 (see Figure 6)。The filter housing 10 has a total of four locking notches 14 such that each of the four locking lugs 66 of the filter unit 50 (two locking lugs for each side retainer) interacts with a locking notch. One of the locking notches 14 can be seen in Figure 1 .

[0045] Figure 6 It is also shown that the sealing ridge 63 of the end edge 62 of the second side retainer 54 contacts the third side edge 36 (the same applies to the corresponding sealing ridge 63 of the first side retainer 53 or the sealing ridge 63 of the opposite end edge 62 that interacts with the first side edge 34). Thus, the four sealing ridges 63 complete the circumferential seal between the frame 31 and the filter unit 50.

[0046] In Figure 1 's diagram, Figure 1 it is shown that the lower side wall 13 has several parallel guiding ribs 15. The upper side wall 13 of the filter housing 10 also has such guiding ribs, but they are hidden in the Figure 1 diagram. Chamfers 16 are provided at the ends of each guiding rib 15 (also see Figure 7 ). When the filter unit 50 is pushed into the filter housing, the overhang 59 slides along the guiding ribs 15 and is then further deformed by the chamfers 16 shortly before reaching the operating position, and then engages behind the locking surface 17 of the guiding chamfers 16 after reaching the operating position. However, the filter unit 50 is mainly held in the operating position by the four locking connections of the locking lugs 66 and the locking notches 14 described above. The side retainers 53, 54 are made of a semi-flexible plastic such as polyurethane, so that on the one hand, a good sealing effect is achieved by means of the sealing ribs 61, the sealing ridges 63 and the sealing lips 64, and on the other hand, the locking of the locking lugs 66 in the locking notches 14 is achieved.

[0047] List of reference numerals

[0048] 1 Air filter

[0049] 2 Air flow / arrow

[0050] 10 Filter housing

[0051] 11 Air inlet

[0052] 12 Air outlet

[0053] 13 Side wall

[0054] 14 Locking notch

[0055] 15 Guiding rib

[0056] 16 Chamfer

[0057] 17 Locking surface

[0058] 20 Blower

[0059] 21 Input

[0060] 30 Blower carrier

[0061] 31 Frame

[0062] 32 Transition section

[0063] 33 First side edge

[0064] 34 Second side edge

[0065] 35 Inclined part

[0066] 36 Third side edge

[0067] 37 Fourth side edge

[0068] 50 Filter unit

[0069] 51 Filter element (51a to 51f)

[0070] 52 Joining edge

[0071] 53 First side retainer

[0072] 54 Second side retainer

[0073] 55 Groove

[0074] 56 Substrate

[0075] 57 Outer end

[0076] 58 First sheet-like part

[0077] 59 Protrusion

[0078] 60 Second sheet-like part

[0079] 61 Sealing rib

[0080] 62 End edge

[0081] 63 Sealing ridge

[0082] 64 Sealing lip

[0083] 65 Free end

[0084] 66 Locking lug.

Claims

1. An air filter (1), comprising: - a filter housing (10); a blower (20) which is arranged in the filter housing (10) and is used to generate an air flow (2) from an air inlet (11) to an air outlet (12); a filter unit (50) arranged in an operating position between an air inlet (11) and an air outlet (12) in the filter housing (50), the filter unit (50) comprising: a plurality of filter elements (51), wherein an outer filter element (51a) and an adjacent filter element (51b) are arranged at an angle to each other and connected to each other at a junction (52), and a first side retaining member (53) and a second side retaining member (54), wherein the first side retaining member (53) and the second side retaining member (54) are used to fix the filter element (51), Characterized in that a first sheet-like piece (58) made of flexible material is attached to the outer end (57) of the outer filter element (51a) and extends parallel to the joining edge (52), the first sheet-like piece (58) is not attached over the entire width, but has an unattached free overhang (59), and in the operating position of the filter unit (50), the overhang (59) abuts against a first abutment surface in a deformed state, wherein the restoring force of the flexible material presses the overhang (59) sealingly against the first abutment surface.

2. The air filter (1) according to claim 1, characterized in that The first side retainer (53) and the filter housing (50) comprise a locking lug (66) and a locking recess (14), wherein in a locked state the connection between the locking lug (66) and the locking recess (14) holds the filter unit (50) in an operating position.

3. The air filter (1) according to one of claims 1 to 2, characterized in that A frame (31) having a flow cross section is provided in the interior of the filter housing (10), which cross section is substantially completely covered by the base of the filter unit (50), wherein a first side edge (33) of the frame (31) forms the first abutment surface.

4. The air filter (1) according to claim 3, characterized in that The base is rectangular.

5. The air filter (1) according to claim 3 or 4, characterized in that: The frame (31) has a second side edge (34) that is perpendicular to the first side edge (33) and forms a second abutment surface facing the first side retainer (53).

6. The air filter (1) according to claim 5, characterized in that An elongated sealing rib (61) is provided on the outer surface of the first side retainer (53), which sealing rib (61) abuts against the second abutment surface in the operating position of the filter unit (50).

7. The air filter (1) according to claim 6, characterized in that The sealing rib (61) extends over the entire length of the first side retainer (53) and forms a sealing ridge (63) at the end edge (62) which, in the operating position of the filter unit (50), bears against the first bearing surface.

8. The air filter (1) according to any one of claims 5 to 7, characterized in that The first side retainer (53) comprises a sealing lip (64) having a free end (65) abutting against the inclined portion (35) of the second side edge (34).

9. The air filter (1) according to any one of claims 1 to 8, characterized in that On the side wall (13) of the filter housing (10) there is at least one guide rib (15) having a rear locking surface (17), behind which the first flap (58) engages when the filter unit (50) reaches an operating position when inserted into the filter housing (10).

10. The air filter (1) according to any one of claims 1 to 9, characterized in that The flexible material is a non-woven fabric.

11. A filter unit (50) for an air filter (1), the air filter (1) comprising a filter housing (10) and a blower (20) arranged in the filter housing (10) for generating an air flow (2) in the filter housing (10), the filter unit (50) comprising: - a plurality of filter elements (51), wherein an outer filter element (51a) and an adjacent filter element (51b) are arranged in a V-shape and connected to each other at a joint edge (52), and a first lateral retaining element (53) and a second lateral retaining element (54), between which the filter element (51) extends in the direction of the joining edge (52), Characterized in that a first sheet-like piece (58) made of flexible material is attached to the outer end (57) of the outer filter element (51a) and extends parallel to the joining edge (52), the first sheet-like piece (58) is not attached over the entire width, but has an unattached free overhang (59), and in the operating position of the filter unit (50) in the filter housing (10), the overhang (59) rests in a deformed state on a first abutment surface, wherein the restoring force of the flexible material presses the overhang (59) sealingly against the abutment surface.

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