FILTER ELEMENT FOR USE IN A FILTER, AND FILTER COMPRISING A FILTER ELEMENT

Abstract

A filter element, in particular a replaceable filter element, more particularly for separating particles and/or gases and/or liquids, in particular a filter cartridge for use in a filter, more particularly a compressed air filter, in particular as a component of a filter comprising multiple filtration stages, includes a substantially tubular body with an annular end face that faces a filter head, an underside, and a circumferential surface. Multiple, preferably four, retaining arms, running radially in relation to the central axis, are provided in the region of the end face and a toroidal filter-element sealing surface is provided on the end face, and the retaining arms protrude in relation to the filter-element sealing surface. The filter element is usable in a filter.

Claims

1-14. (canceled)

15. A filter element comprising a substantially tubular body, having an annular end side that faces a filter head, a lower side which is spaced apart from the end side and faces away from the filter head, a circumferential face which extends along a central axis, wherein the circumferential face connects the end side and the lower side to one another, wherein a plurality of holding arms that run radially to the central axis are provided in the region of the end side, wherein an annular filter element sealing face is provided on the end side, wherein the holding arms project in relation to the filter element sealing face.

16. The filter element of claim 15, wherein the holding arms are substantially L-shaped and/or the holding arms project outwards in the axial direction and/or in the radial direction in relation to the filter element sealing face and/or the holding arms project radially outwards on the circumferential face.

17. The filter element of claim 15, wherein the holding arms are fixedly connected to the filter element sealing face.

18. The filter element of claim 15, wherein the holding arms have in each case a support face which points in the opposite direction of the filter element sealing face wherein the support face is convexly curved and/or the spacing between the filter element sealing face and the support faces in the axial direction is between 0 and 4 millimeters.

19. The filter element of claim 15, wherein the holding arms have in each case an end face which is situated at an exposed end of the respective holding arm that in the radial direction points away from the circumferential face, wherein the spacing between the center of the filter element sealing face and the end face is between 12 and 18 millimeters in the radial direction.

20. The filter element of claim 15, wherein the filter element is designed in such a manner that substantially only axial forces act on the filter element sealing face, wherein the holding arms form a counter bearing in relation to the axial forces, wherein the holding arms are flexible in the axial direction and form a compensation element between the sealing member bearing on the filter element sealing face and receptacle installations which receive the holding arms.

21. A filter having at least one filter head, one filter sleeve and one filter element, wherein a sealing member is furthermore provided which bears against the annular filter element sealing face of the filter element in such a manner that the sealing member between the filter head and the filter element separates an external space, which is situated outside the filter element and within the filter sleeve, from an internal space, which is situated within the filter element.

22. The filter of claim 21, wherein the filter sleeve is substantially tubular and is provided with an open filter sleeve end side that faces the filter head and a filter sleeve outside running along the lateral surface, wherein the filter sleeve surrounds the filter element and delimits the filter element from the environment, wherein the filter sleeve end side has receptacle installations for the holding arms, wherein the filter element is in contact with the filter sleeve only by way of the holding arms disposed in the receptacle installations and is otherwise freely suspended in the filter sleeve.

23. The filter of claim 21, wherein the receptacle installations are formed at least by continuous incisions which begin on the filter sleeve end side and run radially to the central axis, wherein the receptacle installations receive the holding arms, wherein the ends of the incisions form counter bearings which are convex in shape to match concave support faces, wherein the counter bearings absorb the compression force which is created as a result of the compression of the sealing member.

24. The filter of claim 21, wherein the sealing member is an axially acting seal, wherein the filter sleeve by means of a radial seal seals toward the filter head.

25. The filter of claim 21, wherein at least two of the receptacle installations are designed as receptacle locking installations which serve to receive the holding arms and retaining bolts, which are attached to the filter head and/or are aligned radially to the central axis, wherein the receptacle locking installations are designed in such a manner that the retaining bolts interact with the receptacle locking installations in the manner of a bayonet closure.

26. The filter of claim 21, wherein the receptacle locking installations, in addition to the axial incisions, have a fastening extension, wherein the fastening extension is formed by a further incision that starts from the axial incisions and runs substantially circumferentially around parts of the filter sleeve, wherein the fastening extension has a latching undercut which is formed by a concavity in the end region of the fastening extension proximal to the filter head.

27. The filter of claim 21, wherein a sealing arrangement for the fluid-tight sealing between the filter head and the filter element is provided, wherein the sealing arrangement, in addition to the sealing member and the filter element sealing face, comprises a filter head sealing face, wherein the annular, elastic sealing member has a filter head side that faces the filter head sealing face, an opposite filter element side that faces the filter element sealing face, an inner face encircling the inside and has an opposite outer face encircling the shell face, wherein the filter head sealing face and the filter element sealing face are composed of at least one encircling inner partial face and one encircling outer partial face, wherein the sealing arrangement is designed in such a manner that, when impinged with pressure, the sealing member, proceeding from the internal face and/or the external face, in the direction of the acting force is wedged between the inner partial faces and/or the outer partial faces.

28. The filter of claim 21, wherein at least two filter stages are provided, each having a filter head, a filter sleeve and a filter element, wherein the sealing arrangements for sealing between the filter elements and filter heads, the receptacle installations of the filter sleeves and the holding arms of the filter elements of the at least two filters are substantially of an identical design.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The invention will hereinafter be explained by means of the figures described. In the figures:

[0052] FIG. 1 shows a fragment of a sectional view of a filter stage having a sealing arrangement and a filter element;

[0053] FIG. 2 shows a fragment of a sectional view of a sealing arrangement;

[0054] FIG. 3 shows an enlarged fragment of a sectional view of a sealing arrangement;

[0055] FIG. 4 shows a force action diagram of a sealing member stressed axially and circumferentially;

[0056] FIG. 5 shows a perspective view of a filter element;

[0057] FIG. 6 shows a perspective view of a filter sleeve having a filter element;

[0058] FIG. 7 shows a partial section of a view of a filter head from below; and

[0059] FIG. 8 shows a lateral view of a multi-stage filter.

DETAILED DESCRIPTION

[0060] Shown in FIGS. 1 and 2 is a sealing arrangement 1 for a filter, in particular a compressed air filter, in particular as part of a filter having a plurality of filter stages 45, for the fluid-tight sealing between a filter element 2, in particular a filter cartridge, and a filter head 3. Furthermore shown is an annular, elastic sealing member 4 and a filter head and filter element sealing face 5, 6.

[0061] The sealing member 4 has a filter head side 7 that faces the filter head sealing face 5, an opposite filter element side 8 that faces the filter element sealing face 6, an internal face 9 encircling the inside, and an opposite external face 10 encircling the shell face. The filter head side 7 has an encircling first concavity 11 between the inner face 9 and the outer face 10, wherein the filter element side 8 also has an encircling second concavity 12 between the inner face 9 and the outer face 10.

[0062] The filter head sealing face 5 and the filter element sealing face 6 are composed of at least one encircling inner partial face 13 and one encircling outer partial face 14. It can be seen from the drawings that the filter head side 7, at least in regions, bears in an encircling manner on the filter head sealing face 5, and the filter element side 8, at least in certain regions, bears in an encircling manner on the filter element sealing face 6. The partial faces 13, 14 of the filter head sealing face 5 and the partial faces 13, 14 of the filter element sealing face 6 here ascend toward the center between the partial faces 13, 14 in such a manner that the mutual spacing of the inner partial faces 13 decreases from the inside outwards and the spacing between the outer partial faces 14 decreases from the outside inwards, in the axial direction toward the central axis 18. It can likewise be seen that the inner face 9 and outer face 10 of the sealing member 4 come to bear neither proximal to the filter head nor proximal to the filter element and accordingly only seal axially to the central axis 18.

[0063] Furthermore shown is a radial seal 46 which between the filter head 3 and the filter sleeve 33 seals the filter toward the environment or toward the surrounding atmosphere. This seal 46 is a seal 46 which substantially seals by way of forces acting radially to the central axis 18.

[0064] As can likewise be seen from FIGS. 1 and 2, the partial faces 13, 14 interact with the concavities 11, 12 in such a manner that, when impinged with pressure, the sealing member 4, proceeding from the inner face 9 and/or the outer face 10, is wedged in the direction of the acting force F.sub.1, F.sub.2, between the inner faces 13 and/or the outer faces 14 wedged. As a result of this wedging effect, the seal seat between the partial faces 13, 14 and the concavities 11, 12 is reinforced, wherein the acting force F.sub.1, F.sub.2 is created only when there is a pressure difference between the inner face 9 and the outer face 10. The forces that act on the sealing faces 5, 6 when the outer face F.sub.1 of the sealing arrangement 1 is stressed, are illustrated in FIG. 4.

[0065] As can furthermore be derived from FIG. 1, the sealing arrangement 1 is configured for use in a filter, wherein the assembly of the filter element 2 on the filter head 3 takes place along an assembly axis which runs so as to be identical to the central axis 18 of the sealing member 4.

[0066] The sealing member 4 bears on the annular filter element sealing face 6 of the filter element 2 and between the filter head 3 and the filter element 2 separates an external space 31, which is situated outside of the filter element 2, from an internal space 32, which is situated inside the filter element 2.

[0067] In FIG. 3 it is shown that the sealing member 4 on the filter head side 7 has an encircling retaining groove 15 for receiving a retaining element 16. The retaining element 16 is designed in such a manner that, when interacting with the retaining groove 15, a releasable latching connection 17 is created. The latching connection 17 holds the filter head side 7 so as to bear on the filter head sealing face 5, wherein the retaining groove 15 runs in the region of the concavities 11, 12, preferably in the base of the first concavity 11. The retaining element 16 projects between the two partial faces 13, 14 of the filter head sealing face 5. In particular, the retaining element 16 projects along a circular ring in relation to the filter head sealing face 5.

[0068] The second concavity 12 extends at least over half, preferably more than two thirds, of the width of the filter element side 8 between the inner face 9 and the outer face 10. The first concavity 11 extends at least over half, here over more than two thirds, of the width of the filter head side 7 between the inner face 9 and the outer face 10.

[0069] In an encircling sub-region of the second concavity 12, which is preferably situated in the region of the lowest point of the second concavity 12, the sealing member 4 does not bear on the filter element sealing face 6. As can be seen, the sealing member 4 does not bear in that region that is closest to the filter head sealing face 5.

[0070] As can likewise be seen from FIG. 3 and also from FIG. 4, the retaining element 16 and the retaining groove 15 are designed in such a manner that a there is a seal seat between the base of the retaining groove 15 shown in FIG. 4 and that region of the retaining element 16 that is closest to the filter element sealing face 6. This is achieved in that the depth of the retaining groove 15 of the seal in the non-assembled state of the sealing member 4 is at least as great as the height of the retaining element 16 in the direction of the central axis 18, preferably less than the height of the retaining element 16.

[0071] It is furthermore shown that the latching connection 17 is formed by a unilateral extension 19 on the retaining element 16 and a corresponding recess 20 in the sealing member 4. The extension 19 in the radial direction projects outwards to a central axis 18 of the sealing member 4 shown in FIG. 1. The opposite side of the retaining element 16 has no convexity and is flat in the direction of the central axis 18. The retaining element 16 is substantially L-shaped, this being shown in a mirror-inverted manner in FIG. 3.

[0072] The sealing member 4 shown moreover has a hardness between 60 Shore A and 80 Shore A, preferably 70 Shore A.

[0073] In FIG. 4 it is shown that the partial faces 13, 14 of the filter head sealing face 5 and the filter element sealing face 6 in the radial direction to the central axis 18 are at a mutual internal angle α of less than 180°, preferably between 130° and 170°. Furthermore, the filter head side 7 of the sealing member 4 has two annular encircling partial sealing faces 23, 24, between which the holding groove 15 extends into the sealing member 4. Both partial sealing faces 23, 24 in the radial direction to the central axis 18 have a mutual external angle αl of less than 180°, preferably between 125° and 175°.

[0074] Because the sealing member 4 in FIG. 4 is shown in the compressed state, it is obvious that the second concavity 12 in the non-assembled state has a greater depth in the direction of the central axis 18 than the partial faces 13, 14 in the direction of the filter head 3 extend toward the center between the two partial faces 13, 14. For example, a shown compression of the sealing member 4 is achieved when the height of the partial faces 13, 14 is less than 70% of the depth of the second concavity 12.

[0075] As can be seen from the distribution of forces and the exposed inner and outer faces 9, 10, the sealing member 4 is an axially acting seal which seals substantially only by way of axially acting forces.

[0076] Shown in FIG. 5 is a corresponding filter element 2 which is illustrated here as a filter cartridge. The filter element 2 has a filter element sealing face 6 which is set back from an end side 21 of the filter element 2. In other words, the end side 21 is formed by an encircling collar 22 that projects in relation to the filter element sealing face 6.

[0077] The filter element 2 shown is an exchangeable filter element 2 which can be used to separate particles and/or gases and/or liquids. In particular, this is a filter cartridge that can be conceived for use in a filter, in particular a compressed air filter. The filter may be equipped with a plurality of filter stages.

[0078] The filter element 2 shown comprises a substantially tubular body 27 having an annular end side 21 that faces a filter head 3 shown, inter alia, in FIG. 1 and FIG. 7. Furthermore, the filter element 2 has a lower side 28 which is spaced apart from the end side 21 and faces away from the filter head 3. In addition, the filter element 2 has a circumferential face 29 which extends along a central axis 18, in particular a rotation axis. As can be seen, the circumferential face 29 connects the end side 21 and the lower side 28 to one another. Furthermore shown in the region of the end side 21 are a plurality of, preferably three, particularly preferably four, holding arms 30 that run radially to the central axis 18. There is an annular filter element sealing face 6 on the end side 21. The holding arms 30 project in relation to the filter element sealing face 6 and/or in relation to the end side 21.

[0079] The holding arms 30 are substantially L-shaped. Moreover, the holding arms 30 project outwards in the axial direction and in the radial direction relative to the filter element sealing face 6 and/or the end side 21, wherein the holding arms 30 project radially outwards from the circumferential face 29.

[0080] As can likewise be seen from FIG. 5, the holding arms 30 are fixedly connected to the filter element sealing face 6, preferably configured so as to be integral to the filter element sealing face 6.

[0081] It is also shown that the holding arms 30 have in each case a support face 47 which points in the opposite direction of the filter element sealing face 6. The support face 47 is curved so as to be convex. The convex curvature of the support faces 47 here extends in the axial direction to the central axis 18, wherein the support faces 47 adjoin the free ends of the holding arms 30, preferably the end sides 49, and have a length of at least 2 millimeters and a maximum of 8 millimeters in the radial direction. A length between 3 and 6 millimeters is particularly advantageous. Such dimensions permit the easy removal of the filter element 2 and at the same time offer a sufficient support face 47 as a counter bearing to the receptacle installations 36.

[0082] The holding arms 30 have an end face 49 which is situated at that exposed end of the holding arms 30 that points radially away from the circumferential face 29 and thus away from the central axis 18. The spacing between the center of the filter element sealing face 6 and an end face 49 in the radial direction to the central axis 18 here is between 12 and 18 millimeters. A spacing between the end faces 49 and the center of the filter element sealing face 6 of between 14 and 16 millimeters is particularly advantageous. The spacing between the filter element sealing face 6 and the beginning of the support faces 47 in the axial direction is between 0 and 4 millimeters, preferably between 1 and 2 millimeters.

[0083] The filter element 2 is designed in such a manner that substantially only axial forces act on the filter element sealing face 6. The holding arms 30 form a counter bearing 50 in relation to the axial forces that are created as a result of the compression of the sealing member 4 shown in FIG. 1, the latter bearing on the filter element sealing face 6.

[0084] It is of particular advantage that the holding arms 30 are flexible in the axial direction and thus form a compensation element between the sealing member 4 bearing on the filter element sealing face 6 and the receptacle installations 36 shown in FIG. 6. The receptacle installations 36 receive the holding arms 30.

[0085] The filter element 2 at the transition between the holding arms 30 and the circumferential face 29 has centering ramps 48 which have an angle of between 70° and 5° in relation to the central axis 18 and from the circumferential face 29 extend in the direction of the holding arms 30. It is particularly advantageous if the angle between the circumferential face 29 and the centering ramps 48 is between 20° and 40°. The centering ramps 48 connect the circumferential face 29 and the support faces 47 to one another, wherein the centering ramps 48 serve to center the filter element 2 in the surrounding filter sleeve 33.

[0086] FIG. 6 shows a substantially tubular filter sleeve 33 having a filter element 2, wherein the filter sleeve 33 has an open filter sleeve end side 34 that faces the filter head 3 and a filter sleeve outside 35 running along the lateral surface. The filter sleeve 33 surrounds the filter element 2 and delimits the interior of the filter from the environment. The filter sleeve end side 34 has receptacle installations 36 for the holding arms 30, wherein the filter element 2 is in contact with the filter sleeve 33 only by way of the holding arms 30 disposed in the receptacle installations 36 and is otherwise freely suspended in the filter sleeve 33.

[0087] The receptacle installations 36 are formed at least by continuous axial incisions 38 which begin at the filter sleeve end side 34 and run radially to the central axis 18, the receptacle installations 36 receiving the holding arms 30. The ends of the incisions 38 form counter bearings 50 which are concave in shape to match the convex support faces 47 of the holding arms 30, wherein the counter bearings 50 absorb the compression force which is created as a result of the compression of the sealing member 4.

[0088] Two of the receptacle installations 36 are designed as receptacle locking installations 51 which serve to receive the holding arms 30 and the retaining bolts 37 shown in FIG. 8. The retaining bolts 37 are attached to the filter head 3 and aligned radially to the central axis 18. The receptacle locking installations 51 are designed in such a manner that the retaining bolts 37 interact with the receptacle locking installations 51 in the manner of a bayonet closure.

[0089] In addition to the axial incisions 38, the receptacle locking installations 51 have a fastening extension 39, wherein the fastening extension 39 is formed by an additional incision that starts from the axial incisions 38 and runs substantially in the circumferential direction about parts of the filter sleeve 33. The fastening extension 39 furthermore has a latching undercut 40 which is formed by a concavity in the end region of the fastening extension 39 proximal to the filter head.

[0090] Shown from below in FIG. 7 is a filter head 3, wherein the filter sleeve 33 and the filter element 2 are not shown. The filter head 3 has a filter head sealing face 5 on which the sealing member 4 shown in FIGS. 1 to 3 bears. As can be derived from the drawing, holding arm recesses 41 which are set back in relation to the filter head sealing face 5 are provided, wherein the holding arms 30 in the assembled state extend into the holding arm recesses 41.

[0091] The filter head 3 also has a hollow-cylindrical filter sleeve end side recess 42 which from the filter head sealing face 5 in a substantially axially symmetrical manner to the central axis 18 extends into the filter head 3 and, in the assembled state, receives the filter sleeve end side 34, wherein the filter sleeve end side recess 42 in the radial direction to the central axis 18 is situated outside the filter head sealing face 5.

[0092] The filter head 3 moreover has two retaining bolt bores 43, which run radially to the central axis 18 and are preferably opposite one another, wherein the retaining bolt bores 43 receive retaining bolts 37 which preferably interact with the receptacle installations 36 in the filter sleeve 33 from FIG. 6 in the manner of a bayonet closure, preferably wherein a metal-on-metal cone seal 44 is provided between the retaining bolts 37 and the filter head 3.

[0093] Shown in FIG. 8 is a multi-stage filter 45 having a plurality of filter stages, wherein the filter stages additionally or alternatively to the sealing arrangement 1 and/or the filter element 2 comprise features described above. Here, the multi-stage filter 45 includes, inter alia, filter elements 2 having different filter properties.

[0094] In such a multi-stage filter 45, the sealing arrangements 1 for sealing between the filter elements 2 and the filter heads 3 and/or the receptacle installations 36 of the filter sleeves 33 and/or the holding arms 30 of the filter elements 2 can be designed so as to be substantially identical to one another in accordance with the above features.

[0095] Moreover, at least one of the filter elements 2 can be pressurized from the outside with higher pressure than from the inside, wherein at least one of the filter elements 2 is pressurized in reverse.