Filter insert for a filter device

Abstract

A filter insert for a filter device, having a filter element arranged on a longitudinal axis extending there through and a front-side flow opening arranged on the front side of the filter element with the longitudinal axis extending through the flow opening. The filter element has, with respect to the longitudinal axis, at least one flattened portion with a reduced radial extension or a through hole along the periphery of the flow opening the shortest interior distance in the filter element immediately adjacent to the front-side flow opening is shorter than the inside diameter of the front-side flow opening.

Claims

1. A filter insert for a filter device, comprising: a filter element arranged on a longitudinal axis extending there through; a front-side flow opening arranged on the front side of the filter element with the longitudinal axis extending through the flow opening; wherein the filter element has an elongate cross section; and wherein the filter element has, with respect to the longitudinal axis, at least one flattened portion with a reduced radial extension or a through hole along the periphery of the flow opening; wherein the shortest interior distance (a) in the filter element immediately adjacent to the front-side flow opening is shorter than the inside diameter (d) of the front-side flow opening; and wherein the front-side flow opening is arranged on the filter element on a flow pipe around which the filter element engages at least partially, at least one flow opening being disposed in the wall of the flow pipe in a section around which the filter element engages.

2. The filter insert as set forth in claim 1, wherein the filter element encloses a clean space at least partially within an interior of the filter element; and wherein the front-side flow opening on the filter element is in flow communication with the clean space.

3. The filter insert as set forth in claim 1, wherein the longitudinal axis extending through the front-side flow opening lies transverse to a direction of flow of the filter element.

4. The filter insert as set forth in claim 1, wherein a plug-in part is plugged into the flow pipe, the plug-in part being shorter in length than the flow pipe.

5. The filter insert as set forth in claim 4, wherein the plug-in part is plugged via the front-side flow opening into the flow pipe.

6. The filter insert as set forth in claim 5, wherein the plug-in part has a tulip-shaped widening in a region arranged in the flow pipe.

7. The filter insert as set forth in claim 1, wherein flow-conducting elements are arranged on an exterior side of the flow pipe.

8. The filter insert as set forth in claim 1, wherein transverse to the longitudinal axis of the flow opening, a hollow base for connecting to a housing-side fastening element is introduced into the filter insert, which is separated in a flow-tight manner from a filtered side of the filter element; wherein the hollow base projects through an interior of the filter element.

9. The filter insert as set forth in claim 1, wherein the hollow base is arranged within the flow pipe.

10. The filter insert as set forth in claim 1, wherein the filter element engages around the front-side flow opening over an angular range of at least 180 degrees about the longitudinal axis; wherein the filter element has a through hole on a periphery of the front-side flow opening that is no more than 90 degrees with respect to a circumferential direction of the front-side flow opening.

11. The filter insert as set forth in claim 1, wherein the filter element engages around the front-side flow opening over an angular range of no more than 90 degrees; wherein two opposing filter elements are arranged on the front-side flow opening.

12. The filter insert as set forth in claim 1, wherein an interior distance of the filtering medium of the filter element is shorter than an inside diameter of the front-side flow opening.

13. The filter insert as set forth in claim 1, wherein the filter element is embodied as a folded filter, having folded filtering medium.

14. The filter insert as set forth in claim 1, wherein the filter element has an at least approximately U-shaped cross section; wherein legs of the U-shaped cross section enclose a filtered side of the filter element; and wherein the front-side flow opening lies transverse to a longitudinal extension of the legs.

15. The filter insert as set forth in claim 1, wherein a secondary outflow opening is arranged on a filtered side of the filter element and spaced apart from the front-side flow opening; wherein the secondary outflow opening is associated with a secondary nozzle in a filter housing in which the filter element is arranged.

16. A filter insert for a filter device, comprising: a filter insert with a filter element, according to claim 1; wherein an open recess is arranged in the filter element proximate to the front side into which a connecting piece having the front-side flow opening is inserted.

17. The filter insert as set forth in claim 16, wherein the connecting piece has two tabs covering the recess.

18. The filter insert as set forth in claim 17, wherein at least one tab of the two tabs is convexly arched and rises over an outside of the filter element.

19. The filter insert as set forth in claim 1, wherein the filter element encloses a different-sized area face at its opposing end plates; wherein a transition from the front end plate to the opposing rear end plate is conical.

20. The filter device as set forth in claim 1, wherein the shortest interior distance (a) in the filter element immediately adjacent to the front-side flow opening along a tangent to an outside diameter of the flow opening is shorter than the inside diameter (d) of the front-side flow opening; wherein the flow pipe is centered on and elongated along the longitudinal axis; and wherein the filter element has a first interior distance in the filter element in a first direction traverse to the longitudinal axis is shorter than a second interior distance in a different second direction traverse to the longitudinal axis.

21. A filter device, comprising: a filter insert according to claim 1; a filter housing with a receiving space for receiving the filter insert; a housing nozzle arranged on the filter housing and communicating with a filtered side of the filter element whose diameter is at least 50% of a height of the receiving space for the filter insert.

22. The filter device as set forth in claim 21, wherein the height of the receiving space in the filter housing is no more than half of a width and/or a length of the receiving space.

23. A filter insert for a filter device, comprising: a filter element arranged on a longitudinal axis extending there through; a front-side flow opening arranged on the front side of the filter element with the longitudinal axis extending through the flow opening; wherein the filter element has an elongate cross section; and wherein the filter element has, with respect to the longitudinal axis, at least one flattened portion with a reduced radial extension or a through hole along the periphery of the flow opening; wherein the shortest interior distance (a) in the filter element immediately adjacent to the front-side flow opening is shorter than the inside diameter (d) of the front-side flow opening, and, the filter element engages around the front-side flow opening over an angular range of at least 180 degrees about the longitudinal axis; wherein the filter element has a through hole on a periphery of the front-side flow opening that is no more than 90 degrees with respect to a circumferential direction of the front-side flow opening.

24. The filter insert as set forth claim 23, wherein the front-side flow opening is arranged on the filter element on a flow pipe around which the filter element engages at least partially, at least one flow opening being disposed in the wall of the flow pipe in a section around which the filter element engages.

25. A filter insert for a filter device, comprising: a filter element arranged on a longitudinal axis extending there through; a front-side flow opening arranged on the front side of the filter element with the longitudinal axis extending through the flow opening; wherein the filter element has an elongate cross section; and wherein the filter element has, with respect to the longitudinal axis, at least one flattened portion with a reduced radial extension or a through hole along the periphery of the flow opening; wherein the shortest interior distance (a) in the filter element immediately adjacent to the front-side flow opening is shorter than the inside diameter (d) of the front-side flow opening, and, the filter element has an at least approximately U-shaped cross section; wherein legs of the U-shaped cross section enclose a filtered side of the filter element; and wherein the front-side flow opening lies transverse to a longitudinal extension of the legs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Additional advantages and expedient embodiments can be derived from the other claims, the description of the figures and the drawings.

(2) FIG. 1 shows a perspective view of a filter device with a filter insert in a receiving space of a filter housing, the filter insert having two diagonally opposing filter elements with a U-shaped cross section arranged on an outflow pipe, and the outflow pipe being connected to a housing nozzle on the filter housing,

(3) FIG. 2 shows the filter device according to FIG. 1 from another perspective,

(4) FIG. 3 shows a partially sectional top view of the filter device,

(5) FIG. 4 shows a side view of the filter device with a representation of the housing nozzle for discharging the cleaned fluid,

(6) FIG. 5 shows a section through the filter device,

(7) FIG. 6 shows an enlarged representation of detail VI from FIG. 5,

(8) FIG. 7 shows an enlarged representation of detail VII from FIG. 5,

(9) FIG. 8 shows a sectional, schematic representation of a filter insert with a filter element embodied as a folded filter that engages partially around an outflow opening,

(10) FIG. 9 shows another exemplary embodiment with two separate filter elements, each of which borders on the outflow opening,

(11) FIG. 10 shows another exemplary embodiment with a single filter element at the outflow opening,

(12) FIG. 11 shows a perspective view of a filter insert whose basic structure corresponds to that of FIG. 9, in a partially installed state,

(13) FIG. 12 shows the filter insert according to FIG. 11 in the completely installed state,

(14) FIG. 13 shows a design variant of a filter insert with an oval-shaped outflow opening,

(15) FIG. 14 shows a design variant of a filter device with two separate filter inserts in a receiving space of the filter housing,

(16) FIG. 15 shows a design variant of a filter insert with additional secondary outflow opening arranged on the filtered side of the filter element with a parallel offset to the central outflow opening,

(17) FIG. 16 shows a top view of the filter insert from FIG. 15,

(18) FIG. 17 shows a perspective view of a filter device with a filter insert according to FIGS. 15 and 16,

(19) FIG. 18 shows a sectional view of the filter device from FIG. 17,

(20) FIG. 19 shows a top view of another embodiment of a filter insert.

(21) FIG. 20 shows an exploded view of a filter insert with a filter element with an elongate cross section, a recess being disposed in the filter element in the region of a front side into which a connecting piece is inserted,

(22) FIG. 21 shows a front view of the filter insert according to FIG. 20,

(23) FIG. 22 shows a top view of the filter insert in the assembled state,

(24) FIG. 23 shows a side view of the filter insert,

(25) FIG. 24 shows a perspective view of the filter insert in the assembled state.

(26) In the figures, similar components are designated by the same reference symbols.

DETAILED DESCRIPTION

(27) FIGS. 1 and 2 show a perspective view of a filter device 1, which is embodied as an air filter for a combustion engine and has, in a receiving space 3 in a filter housing 2, a filter insert 4 for filtering the conveyed combustion air. The filter insert forms a structural unit and includes two filter elements 5 and an outflow pipe 6. The two filter elements 5 are arranged on diagonally opposing sides of the outflow pipe 6 and each have an approximately U-shaped cross section. Optionally, V-shaped cross sections of the filter elements can also be considered. The filter elements 5 are each flowed through radially from the outside to the insidein the direction of the outflow pipe 6by the fluid to be filtered. Flow openings are disposed in the wall of the outflow pipe 6 that are connected to the filtered side of the filter elements 5, whereby the fluid travels after filtration via the flow openings into the outflow pipe 6 and is discharged axially via the outflow pipe 6.

(28) One or more flow-conducting devices can be arranged in the outflow pipe 6 and/or in the filter elements 5 to guide the fluid.

(29) A housing nozzle 7 is arranged on the outer wall of the filter housing 2 that includes a recess in the housing wall and to which the outflow pipe 6 is connected. The front-side opening of the outflow pipe 6 forms the outflow opening 8, which rests directly against the housing nozzle 7. A channel or pipe can be connected on the side of the housing nozzle 7 opposite the outflow pipe to discharge the cleaned fluid. In the embodiment as an air filter, the outflow pipe 6 can, as a component of the filter insert 4 and of the housing nozzle, form a part of the suction conduit through which the cylinders of the combustion engine are supplied with fresh air.

(30) As can be seen particularly from FIG. 3, the filter element 5 has a supporting frame 9 that supports the filtering means or medium through which the fluid to be filtered flows. The filter element 5 has an approximate U-shape, the free front sides of the legs of the U-shape resting against the lateral surface of the outflow pipe 6. Accordingly, the rounded U-shape lies on the side facing away from the outflow pipe 6.

(31) The legs of each U-shaped filter element 5 engage around an intermediate clean space, which communicates via the flow openings in the wall of the outflow pipe 6 with the interior of the outflow pipe. On the front side, the filter elements 5 and thus the interposed clean space is sealed by end plates 10 and 11. On the side opposite the outflow opening 8, the end plate 10 additionally seals the rear opening of the outflow pipe 6 as well.

(32) The diameter of the outflow pipe 6 and of the outflow opening 8, which corresponds to the clear diameter of the outflow pipe on its outflow side, is approximately the same size as the height of the filter element 5. The filter elements 5 do not enclose the outflow pipe 6 completely, but rather leave two angular segments along the periphery of the outflow pipe 6 free. The free front sides of the U-shaped filter elements 5 rest against the outer wall of the outflow pipe 6, an angular segment of less than 180, for example approximately 90, on the outer periphery of the outflow pipe 6 being covered by each filter element 5.

(33) The height of the filter insert 4 is significantly shorter than the width or length of the filter insert. The height is particularly no more than half as large as the width and/or the length of the filter insert. The same applies to the dimensions of the receiving space 3 in the filter housing 2 for receiving the filter insert 4.

(34) As can be seen in the sectional representation according to FIG. 5 and from the detailed illustrations according to FIGS. 6 and 7, the receiving space 3 in the filter housing 2 is to be sealed by a detachable housing cover 12. A conduit 13 is connected to the housing nozzle 7, which is plugged into a recess in the filter housing 2, through which the cleaned fluid is discharged. Via the outflow opening 8 that forms the front side of the outflow pipe 6, a plug-in part 14 is plugged into the outflow pipe 6 whose length is less than the length of the outflow pipe 6. The conduit 13 is embodied as a nozzle that is integrally formed with the plug-in part 14, the nozzle 14 projecting only slightly beyond the outflow opening 8 of the outflow pipe 6 and having an overall smaller diameter than the conduit 13. The plug-in part 14 has a diameter that changes over its axial length, initially decreasing continuously starting from the front-side region lying immediately outside of the outflow opening and widening in the manner of a tulip on the opposing front side that projects into the outflow pipe 6. By means of the plug-in part 14, the noise characteristics and possibly the flow characteristics as well can be influenced.

(35) As can be seen in the enlarged illustration according to FIG. 6, a knurl or groove portion 15 can be arranged on the front-side end region of the outflow pipe 6 on the outside with which the outflow pipe 6 is inserted into the larger-sized housing nozzle 7, whereby a sufficiently robust and flow-tight connection is achieved between the outflow side of the outflow pipe 6 and the housing nozzle 7. A corresponding knurl or groove portion can also be arranged on the outer lateral surface of the nozzle-like conduit 13 that is integrally formed with the plug-in part 14, the knurl or groove portion being engaged around by another portion of the housing nozzle 7. This knurl or groove portion can optionally also be embodied as a separate component that is arranged between the outer lateral surface of the nozzle-like conduit 13 and the interior of the housing nozzle 7.

(36) A hollow base 16 is introduced into the outflow pipe 6 through which the outflow pipe 6 passes completely in the radial direction. The hollow base has an elongate, substantially oval-shaped cross section and is used to secure the filter insert 4 in the filter housing 2. The hollow base 16 has a circumferential wall that separates the interior of the hollow base from the interior of the outflow pipe 6 in a flow-tight manner. The interior of the hollow base 16 serves to receive the housing-side fastening elements 17, 18 (FIGS. 5, 7), which are integrally formed with the filter housing 2 and the housing cover 12 and extend orthogonally to the longitudinal axis of the outflow pipe 6 and project into the interior of the hollow base 16. The fastening elements 17, 18 each form a dome that has a smaller cross section than the inside of the hollow base 16, thus enabling a relative axial displacement of the outflow pipe 6 and filter insert 4 along the longitudinal axis of the outflow pipe. The dome-like fastening elements 17, 18 are interconnected via a screw 19 that is inserted via the housing cover 12.

(37) For assembly, the filter insert 4 is first placed into the receiving space 3 of the filter housing 2, the dome-like fastening element 17, which is integrally formed with the filter housing 2 and rises from the bottom of the receiving space, projecting into the interior of the hollow base 16 in the outflow pipe 6. The outflow pipe 6 is then displaced along its longitudinal axis such that the front-side portion of the outflow pipe 6 is pushed with the knurl 15 or groove portion into the housing nozzle 7, which is arranged on the filter housing 2. After that, the plug-in part 13, 14 can be inserted axially via the outflow opening 8 into the outflow pipe 6. Finally, the housing cover 12 is put in place and the dome-like, downwardly projecting fastening element 18 on the housing cover 12 is inserted into the interior of the hollow base 16 in the outflow pipe 6 until the dome-like fastening elements 17, 18 are arranged coaxially to one another and can be securely interconnected by means of the screw 19.

(38) FIGS. 8 to 10 show schematic representations of various exemplary embodiments for filter inserts 4 with filter elements 5 and an outflow opening 8. The outflow opening is located on the front side of the outflow pipe 6, whose inside diameter d, as can be seen in FIG. 8, is larger than the interior distance a between the inner-lying tips of the filter element 5 embodied as a folded filter. The filter element 5 is U-shaped, so that the tips inside of them enclose a clean space whose clear height corresponds to the interior distance a. Insofar as the outflow pipe 6 does not have a round but an oval-shaped cross section, the relationships refer to the radial inner extension of the outflow pipe with respect to the height in the direction of the interior distance a of the filter element 5.

(39) According to one advantageous embodiment, the radial extension d of the outflow pipe 6 is approximately equal to or shorter than the housing height with respect to the vertical direction or the direction of the interior distance a of the filter element 5.

(40) The filter element 5 has two U-shaped portions that are interconnected on one side of the outflow pipe 6, whereas a through hole 20 is disposed on the opposite side on the circumferential side of the outflow pipe 6. The through hole 20 extends in the circumferential direction of the outflow pipe 6 over an angular segment of approximately 90. The free ends of the filter element 5 rest against opposing sides of the through hole on the lateral surface of the outflow pipe 6. In the continuous portion, which is at the top in FIG. 8, the inner-lying tips of the filter element 5 contact the lateral surface of the outflow pipe 6, whereas, as a result of the shorter interior distance a, the tips lying inside of them project farther inward on the opposite side of the filter element.

(41) In the exemplary embodiment according to FIG. 9, the filter insert 4 has two individual, mutually separate filter elements 5, each of which has a U-shaped basic cross section and is embodied as a folded filter. The free front sides of the legs of the U-shaped filter elements rest against the lateral surface of the outflow pipe 6 and engage around a respective angular segment that covers about 90. The two filter elements 5 are arranged diagonally across from one another, whereby, on the periphery of the outflow pipe 6 between the two filter elements 5, a through hole 20 is formed above and below that also extends respectively over an angular segment of about 90. The parallel legs in the U-shaped basic cross section can also be aligned at a certain angle in relation to one another, thus resulting in a V-shaped arrangement or a combined U- and V-shaped arrangement.

(42) In the exemplary embodiment according to FIG. 10, the filter insert 4 includes only one single U-shaped filter element 5, which is embodied as a folded filter and whose free front sides rest against the outer periphery of the outflow pipe 6. The filter element 5 engages around an about 90 angular segment on the periphery of the outflow pipe 6. Accordingly, the through hole 20 covers an angular segment of about 270.

(43) Another exemplary embodiment of a filter insert 4 is shown in FIGS. 11 and 12. The filter insert 4 includes a central outflow pipe 6 to which a supporting frame 9 is connected, a supporting frame 9 being provided for a respective filter element 5 on diagonally opposing sides of the outflow pipe 6. A hollow base 16 is introduced for assembly-related purposes into the outflow pipe 6 in the aforedescribed manner which passes through the outflow pipe 6 orthogonally to its longitudinal axis. Each filter element 5 optionally consists of an outer filtering or covering layer 21 and, in all cases, of an inner-lying filtering means 22, which rests directly on the U-shaped supporting frame 9, so that the filter element 5 with the two layers 21, 22 also has an overall U-shaped cross section. Flow openings 23 are disposed in the wall of the outflow pipe 6 through which the clean space between the legs of the U-shape of the filter element 5 is connected to the interior of the outflow pipe 6.

(44) At the axial ends, the filter elements 5 are covered by end plates 10 and 11, respectively.

(45) In the exemplary embodiment according to FIG. 13, the filter insert 4 also has two filter elements 5 arranged on diagonally opposing sides of the outflow pipe 6 and U-shaped in cross section. The housing nozzle 7 has an oval-shaped cross section; the outflow pipe 6 and the front-side outflow opening 8 are also expediently provided with an oval-shaped cross section. In the preceding exemplary embodiments, on the other hand, the outflow pipe, outflow opening and housing nozzle each have a round cross section.

(46) FIG. 14 shows another design variant of a filter device 1 in which two separate filter inserts 4 are received in the receiving space 3 of the filter housing 2. The filter inserts 4 are of equal construction and, like in the first exemplary embodiment, each consists of two cross-sectionally U-shaped filter elements 5 on diagonally opposing sides of an outflow pipe 6 that is connected to a housing-side nozzle 7.

(47) FIGS. 15 to 18 show another exemplary embodiment of a filter insert 4 and filter device 1 with a filter insert. The filter insert 4 depicted in FIGS. 15 and 16 has basically the same construction as the filter insert shown in FIGS. 11 and 12 and includes a centrally arranged outflow pipe 6 as well as two diagonally opposing filter elements 5 provided with a U-shaped cross section whose open U-side borders the outflow pipe 6. The filter elements 5 are flowed through in the transverse direction with respect to the longitudinal axis of the outflow pipe 6, the filtered side of the filter elements 5 being connected via flow openings in the wall of the outflow pipe 6 to the interior of the outflow pipe, whereby the filtered fluid is discharged axially via the outflow pipe 6 and the front-side outflow opening 8, which is immediately adjacent to the housing nozzle 7.

(48) In addition to the outflow opening 8, a second outlet referred to as a secondary outflow opening 24 is provided on the filtered side of the filter insert 4. The secondary outflow opening 24 is located on the same front side of the filter insert as the primary outflow opening 8, but with a parallel offset. The secondary outflow opening 24 is introduced into the end plate 11 and, in relation to the central outflow opening 8, is laterally offset and adjacent to the U-shape of one of the two filter elements 5. A secondary outflow opening 24 is provided only in the region of the filter element 5, whereas the second filter element 5 has no such secondary outflow opening. However, it can be expedient to provide on both filter elements 5 a respective secondary outflow opening that is offset with respect to the central outflow opening 8. Furthermore, it is possible to arrange the secondary outflow opening 24 on the front side of the filter element opposite the primary outflow opening 8.

(49) A secondary nozzle 25 is associated with the secondary outflow opening 24 and, when mounted in the filter housing 2 (FIGS. 17, 18), projects through a recess in the side wall of the filter housing 2. The secondary nozzle 25, like the housing nozzle 7 associated with the primary outflow opening 8, is provided with a groove portion on the outer lateral surface with which the nozzles 7, 25 are seated in a frictional or force-fitted manner in the recesses in the side wall of the filter housing 2.

(50) FIG. 19 shows another exemplary embodiment of a filter insert 4 that has basically the same construction as in the exemplary embodiment according to FIGS. 11, 12. U-shaped filter elements, whose open U-side is immediately adjacent to the outflow pipe 6, are respectively located on diametrically opposed sides of an outflow pipe 6. Cleaned gas on the interior of the filter elements 5 is conveyed via flow openings into the outflow pipe 6 and discharged from same axially via a front-side outflow opening 8.

(51) Flow-conducting elements 26, embodied so as to be curved, are located on the outer wall of the outflow pipe 6 and extend inward from the outer wall of the outflow pipe 6 in the direction of the respective filter elements 5. The flow-conducting elements [2]6 are intended to support the discharging of the cleaned gas from the interior of the filter elements 5 via the flow openings in the wall into the outflow pipe 6. Several flow-conducting elements 26 are distributed over the axial length of the outflow pipe 6 and extend into each of the two diametrically opposed filter elements 5.

(52) Another exemplary embodiment of a filter insert 4 is shown in FIGS. 20 to 24. The filter insert 4 includes a filter element 5 having an elongate cross section and enclosing an interior space that forms the clean space for the fluid to be cleaned, which flows radially from the outside to the inside through the filtering means of the filter element 5. The cleaned fluid is discharged from the inner-lying clean space axially via an outflow opening 8, whose longitudinal axis coincides with the longitudinal axis of the filter element 5. The outflow opening 8 is formed by a flow ring 29 of a connecting piece 27, which includes, in addition to the flow ring 29, two tabs 30 and 31, which are integrally formed with the flow ring 29. The tabs 30 and 31 are located on a front side of the flow ring 29 and project in the installed state into a recess 28, which is open at the edge and introduced into the filter element 5 in the region of a front side.

(53) The recess 28 extends over the entire height of the filter element 5with respect to the longitudinal axis 32 of the filter elementso the recess 28 extends both through the lower and the upper layer of the filter element. The recess 28 has a rounded cross section that is particularly oval-shaped and includes about half of an oval.

(54) The cross-sectional surface of the tabs 30 and 31 is adapted to the recess 28. In the installed state, the tabs 30 and 31 project into the recess 28 in the region of the opposing outer sides on the long sides of the filter element 5. The overall surface area of the tabs 30 and 31 is preferably slightly larger than the corresponding surface area of the recess 28, in which case each tab 30 and 31 rests in a flow-tight manner on the respective outer side of the filter element 5 or is connected in a flow-tight manner to the outer side, for example through welding or adhesion.

(55) The tabs 30 and 31 are convex with an outwardly oriented curvature. As can be seen from the perspective representations according to FIGS. 20 and 24 as well as from the side view according to FIG. 23, an additional flow path aligned orthogonally to the longitudinal axis 32 is created for the effluent cleaned fluid from the interior of the filter element 5. In the region of the recess 28, a portion of the cleaned fluid runs orthogonally to the longitudinal axis 28 in the direction of the tabs 30 and 31 and is then diverted in the axial direction by the curvature on the inner wall of each tab 30, 31. The majority of the flow can flow off immediately in the axial direction via the flow ring 29.

(56) In the region of each front side, the filter element 5 is provided with an end plate 10 and 11, respectively. The end plate 11 on the side adjacent to the recess 28 can be connected to the connecting piece 27 and lies between the tabs 30 and 31. A flow opening is disposed in the end plate 11 that lies coaxial to the outflow opening 8.

(57) A longitudinal slot 33, through which cleaned fluid can also be discharged from the filter element 5, is disposed in the end plate 10, which is arranged on the side opposite the connecting piece 27 on the front side of the filter element 5.

(58) As is indicated schematically in FIG. 20 on the front side with the recess 28, the filter element 5 is embodied as a folded filter.

(59) Furthermore, a supporting frame 9 that imparts additional stability to the filter element 5 is integrated into the filter element 5. A recess corresponding to the recess 28 in the filter element 5 is also disposed in the supporting frame 9 adjacent to a front side.

(60) As can be seen in FIG. 23, the filter element 5 has, with respect to the longitudinal axis 32, a cone angle at which the longitudinal perimeter sides of the filter element are inclined in relation to the longitudinal axis. As a result, the area cross section that is enclosed by the opposing end plates 11 and 10 of the filter element 5 changes. In the region of the connecting piece 27, which is inserted with its tabs 30 and 31 into the recess 28 of the filter element 5, the front end plate 11 of the filter element has a larger enclosed cross section than on the opposing rear end plate 10. The cone angle lies in a range, for example, from no more than 5 or no more than 2.