Filter element

Abstract

The invention relates to a filter element (10) having a first fluid path (12) on a raw side (60) for filtering a first fluid (64) and a second fluid path (14) having a fluid line (16) on a clean side (62) for carrying a second fluid (66). The filter element (10) is provided at least on one side with a first end plate (20). Here, the fluid line (16) is arranged in the central inner region (36) of the filter element (10) and connected with the end plate (20) for joint disassembly, especially securely connected to the filter element. The invention further relates to a filter system (100) including such a filter element (10).

Claims

1. A filter element, including: a hollow filter media body consisting of: a filter media for filtering a fluid, the filter media circumferentially surrounding and closed circumferentially about a longitudinal element axis and having an open interior region (36) concentric with and arranged on the longitudinal element axis; wherein axial, as used herein, is a direction parallel to the longitudinal element axis; wherein radial, as used herein, is a direction transverse to the longitudinal element axis; the hollow filter media body of filter media, having: a radially outer surface of the filter media of the hollow filter media body forming an inflow face; a radially inner surface of the filter media, within the open interior region (36) of the hollow filter media body, forming an outflow face; a first axial end of the filter media hollow body; and an opposite second axial end of the filter media hollow body; the filter element including: a first end plate (20) arranged directly on the first axial end of the filter media hollow body; a second end plate (21) arranged directly on the opposite second axial end of the filter media hollow body, the filter media extending continuously from the first end plate to the second end plate; an air outflow fluid line (16) formed as a tube and connected to the first end plate, the air outflow fluid line (16) extending axially through an opening in the second end plate into the open interior region of the hollow filter media body; and wherein the air outflow fluid line (16) is securely connected to the first end plate.

2. The filter element according to claim 1, wherein the air outflow fluid line (16) extends from the first axial end of the filter media hollow body to the opposite second axial end of the filter media hollow body through the open interior region (36) and circumferentially surrounded by the hollow filter media body.

3. The filter element according to claim 1, wherein the filter element (10) has an inflow port (122), by means of which the fluid line (16) can be connected to a non-return valve (18), and/or throttle unit during installation of the filter element (10) in a housing (101) of a filter system (100); wherein the inflow port (122) is a stub-shaped protrusion of the air outflow fluid line (16), which protrudes outwardly from an end face of the filter element (10) and/or is arranged coaxially to a longitudinal element axis (129) of the filter element.

4. The filter element according to claim 3, wherein the inflow port (122) has a seal ring (34) for sealing engagement with a valve, the non-return valve (18) and/or throttle unit.

5. The filter element according to claim 1, wherein the filter element has an air outflow port (131), by means of which the air outflow fluid line (16) can be connected to a housing-side outflow channel (40) during installation of the filter element (10) in a housing (101) of a filter system (100).

6. The filter element according to claim 5, wherein the air outflow port (131) is formed as a stub-shaped protrusion on the air outflow fluid line (16) arranged coaxially to the longitudinal element axis (129).

7. The filter element according to claim 6, wherein the air outflow port (131) has a seal ring (48) configured for sealing engagement to a housing-side outflow channel during installation of the filter element (10) in a housing (101).

8. The filter element according to claim 6, wherein the filter element has two circumferential seals (133, 134) in the region of the end face which is below in the installed filter element (10); wherein one of the seals (133) or both seals are oriented radially outward and/or one of the seals (134) or both of the seals are oriented radially inward.

9. The filter element according to claim 6, wherein the stub-shaped protrusion of the air outflow fluid line (16) forms a drain device (50) with a receptacle of the housing, the drain device (50) opening during disassembly of the filter element from the housing (101).

10. A filter system, including a filter housing (101); a filter element according to claim 1 replaceably arranged in a filter housing (101); wherein the filter system (100) includes a receptacle (106) for the air outflow fluid line (16) and/or a receptacle (42) for a non-return valve (18).

11. The filter system according to claim 10, wherein the air outflow fluid line (16) of the filter element is provided for ventilating a fuel management system of an internal combustion engine.

12. The filter system according to claim 10, wherein the non-return valve (18) is attached to an interior side of an upper housing part (102) of the filter housing (101).

13. The filter system according to claim 12, wherein the non-return valve (18) is arranged above the filter body (11) of the filter element (10).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages appear from the following description of drawings. The drawings illustrate exemplary embodiments of the invention. The drawings, description and claims contain numerous features in combination. A person skilled in the art will expediently also consider the features individually and combine them into appropriate further combinations.

(2) FIG. 1 shows a longitudinal section through a filter system according to one embodiment of the invention for fuel filtration in a motor vehicle;

(3) FIG. 2 shows an enlarged view of the upper part of the longitudinal section of FIG. 1 with details of the arrangement of a fluid line and a non-return valve of the filter system;

(4) FIG. 3 shows a longitudinal section through a filter system according to another embodiment for fuel filtration in a motor vehicle with a direct arrangement of a non-return valve in a fluid line;

(5) FIG. 4 shows an enlarged view of the upper part of the longitudinal section of FIG. 3 with details of the arrangement of a non-return valve for ventilation in a fluid line;

(6) FIG. 5 shows a longitudinal section through a filter system according to a further embodiment for fuel filtration in a motor vehicle with two O-rings for sealing a filter element against a filter housing;

(7) FIG. 6 shows a longitudinal section through a filter element with a water separating function, as can be used in the filter system represented in FIG. 5;

(8) FIG. 7 shows a longitudinal section through a filter element without a water separating function, as can be used in the filter system represented in FIG. 5;

(9) FIG. 8 shows an isometric representation of a filter element with a quick coupling according to another embodiment of the invention;

(10) FIG. 9 shows a section through a filter element according to FIG. 8;

(11) FIG. 10 shows a longitudinal section through a filter element with a water separating function according to a further embodiment of the invention;

(12) FIG. 11 shows a longitudinal section through a filter system with a water separating function according to a further embodiment of the invention;

(13) FIG. 12 shows a longitudinal section through a filter system according to a further embodiment for fuel filtration in a motor vehicle with an arrangement of a non-return valve on a housing cover;

(14) FIG. 13 shows a longitudinal section through the filter element of the filter system according to FIG. 12, and

(15) FIG. 14 shows a longitudinal section through a filter system according to a further embodiment for fuel filtration in a motor vehicle with an arrangement of a non-return valve in the fluid line fixed to the element;

DETAILED DESCRIPTION

(16) In the figures, identical or similar components are provided with the same reference characters. The figures are only exemplary and are not meant to be limiting.

(17) The invention is illustrated with reference to a fuel filter, however it may also be provided for other filter systems with corresponding adaptation of the construction.

(18) FIG. 1 shows a longitudinal section through a filter system 100 according to one embodiment of the invention for fuel filtration in a motor vehicle. The filter element 100 has a filter element 10 having a first fluid path 12 for filtering a first fluid 64 from a raw side 60 to a clean side 62 and a second fluid path 14 having a fluid line 16 through a clean side 62 for carrying a second fluid 66 which is connected with the raw side 60, which filter element 10 is provided with a first end plate 20, wherein the fluid line 16 is arranged centrally in the inner region 36 of the filter element 10 and is connected to the end plate 20 for joint disassembly, especially securely connected to the filter element, and the end plate 20 has a bore 38 which is designed such that the fluid line 16 is connected via the bore 38 with an outer region 44 on the raw side 60 of the filter element 10.

(19) During start-up of the filter system 100, the second fluid 66, and thus typically air, are in the fluid line 16, while during operation, the fluid line 16 is filled with the first fluid 64, thus for example fuel, of the raw side 60.

(20) The filter system 100 comprises a central filter housing 101 in two parts, an upper housing part 102 and a lower housing part 104. The upper housing part 102 may be connected here via a screw connection 56 with the lower housing part 104, and be fixed via an inner O-ring seal 58. A hollow cylindrical filter element 10 sits centrally arranged in the filter housing 101, through which correspondingly flows a first fluid 64, in particular fuel, radially from the outer region 44 into an inner region 36 by means of the first fluid path 12, marked by an arrow, said fluid thereby being filtered. The filtering takes place here in the filter body 11 of the hollow cylindrical filter element 10.

(21) In an embodiment not shown, a reverse direction of flow from inside to outside is also conceivable with a corresponding adjustment of the positions of the respective components.

(22) The filter element 10 is connected via a quick coupling 70 in the form of a snap connection with the upper housing part 102, and can thus be pulled out with the unscrewed upper housing part 102 from the lower housing part 104, for example during a change of the filter element 10 for maintenance.

(23) The filter body 11 itself preferably consists of folded filter paper and can be designed to be replaceable. The filter body 11 is stiffened on its inner side by means of a central tube 25, whereby a collapse pressure resistance of the filter body 11 is realized. The filter system 100 can be opened for replacement, for example, via the two-part filter housing 101. The filter element 10 is sealed against the lower housing part 104 with two O-ring seals 46, and in this way separates the outer region 44 from the inner region 36 of the first fluid path, i.e. the raw side 60 from the clean side 62 of the filter system 100. The filtered fluid 64 flows downward via the inner region 36 of the filter element 10 and is conveyed further, for example to the injection system of an internal combustion engine. After removal of the upper housing part 102, the filter element 10 can be pulled out upward, whereby, by means of the arrangement of the two O-ring seals 46, the first fluid 64 still located on the raw side 60 in the outer region 44 of the filter system 100 may drain via an emptying channel 54 and may not enter the clean side 62, i.e. the inner region 36 of the filter element 10 and thus the internal combustion engine. A first end plate 20 is mounted on the upper end of the filter element 10, said cover being flatly and sealingly applied on the filter element 10 and to which cover is adjoined a fluid line 16 in the inner region 36 of the filter element. The fluid line 16 is inserted at the lower end with an O-ring seal 48 into a receptacle 106 of the lower housing part 104. A drain device 50 is likewise mounted on the lower end of the fluid line 16, which, during a replacement of the filter element 10, protects the clean side 62 of the tank system from contamination by separating the first 64 and second fluid 66. A non-return valve 18 is centrally arranged in the upper end plate 20, which non-return valve can be fixed on the upper end plate 20 and/or on the upper housing part 102 via a snap connection 22 and which is sealed against the upper end plate 20 via an O-ring seal 34. The non-return valve 18 is expediently designed as a minimum pressure valve with a non-return function and an opening pressure on the order of 0.4 bar, and is usually always open during operation of an internal combustion engine. A second fluid path 14, which may serve for ventilating the filter system 100, thus leads via the outer region 44 of the filter element 10 into the non-return valve 18 and through a bore 38 in the in the upper end plate 20, which serves as a throttle bore for setting a defined flow resistance and which is preferably designed with a size of 0.5 mm, into the fluid line 16. Air which has been entrained with the fuel from a tank system may thus be led back out of the filter system 100 by means of the non-return valve 18 and the fluid line 16 via an outlet 40. If an internal combustion engine connected to the filter system 100 is turned off, for example in start/stop operation, and as a result no fuel is resupplied from the corresponding tank system, the non-return valve 18 may thus close. The pressure in the filter element 10 is thereby maintained, and the fuel remains in the filter system 100. This provides the conditions for a rapid start of the internal combustion engine. After the re-opening of the non-return valve 18, the ventilation of the filter system 100 again begins to operate.

(24) The filter element 10 is provided with a second end plate 21 on the side opposite the first end plate 20, wherein the fluid line 16 is connected with the second end plate 21.

(25) FIG. 2 shows an enlarged view of the upper part of the longitudinal section of FIG. 1 with details of the arrangement of a fluid line 16 of a non-return valve 18 in the first end plate 20 of the filter element 10. The non-return valve 18 itself is embedded with its valve body 30 in a valve support 32, for example pressed thereinto. The valve support 32, in turn, is inserted by means of an O-ring seal 34 in a corresponding receptacle 42 of the end plate 20 and thus establishes a sealed connection to the end plate 20. The valve support 32 may be fixed on the upper housing part 102 via a snap-on connection 60, so that, when the upper housing part 102 is removed, the non-return valve 18 is pulled out of the receptacle 42 of the upper end plate 20 and remains in the upper housing part 102. In cross-section, the valve body 30 displays the usual design of a non-return valve with a ball 26, which is pressed into a valve seat by means of a spring 28. The end plate 20, in turn, sits sealingly on the filter element 10 and has a connection via the bore 38 to the support tube 24 designed as the fluid line 16. The second fluid path 14 for ventilating the filter system 100 thus leads via the outer region 44 of the filter element 10 through the non-return valve 18 via the bore 38 into the support tube 24 of the filter element 10, said support tube being designed as a fluid line 16.

(26) In FIG. 2 can also be seen the quick coupling 70, in the form of a snap connection, with which the filter element 10 is connected with the upper housing part 102 and which can be pulled out of the lower housing part 104 with said upper housing part.

(27) FIG. 3 shows a longitudinal section through a filter system 100 according to another embodiment of the invention for fuel filtration in a motor vehicle with a direct arrangement of a non-return valve 18 in a fluid line 16. The construction of the filter system 100 is similar to the filter system shown in FIG. 1 with a flow direction from the outside to the inside, which is indicated by the radial arrows from an outer region 44 into an inner region 36 through the filter element 10, i.e. from the raw side 60 into the clean side 62 of the filter system 100.

(28) A hollow cylindrical filter element 10 is arranged in a two-part filter housing 101, wherein the filter element 10 can be designed to be replaceable. The filter system 100 can be opened for replacement, for example, via the two-part filter housing 101. The upper housing part 102 may be connected here via a screw connection 56 with the lower housing part 104, and be fixed via an inner O-ring seal 58.

(29) The filter element 10 is connected via a quick coupling 70 in the form of a bayonet connection with the upper housing part 102, and can thus be pulled out with the unscrewed upper housing part 102 from the lower housing part 104, for example during a change of the filter element 10 for maintenance.

(30) A first fluid path 12 shows the route of the first fluid to be filtered, for example fuel, from an outer region 44 of the filter element 10 radially through the periphery into an inner region 36, i.e. from a raw side 60 to a clean side 62 of the filter system 100. In contrast to the filter system shown in FIG. 1, however, the non-return valve 18 here is arranged directly in the fluid line 16, which in turn is formed in the support tube 24, and radially closes sealingly with the support tube 24 via an O-ring seal 34. The non-return valve 18 may be fixed on the upper housing part 102 via its valve support 32 by means of a snap connection 22. The support tube 24 is an integral component of the filter element 10 and connected to the first end plate 20. The second fluid path 14 for ventilating the filter system 100 leads in a manner analogous to FIG. 1 from the outer region 44 of the filter element 10 through the non-return valve 18 into the fluid line 16, which also opens into an outlet 40. The fluid line 16 is inserted at the lower end with an O-ring seal 48 into a receptacle 106 of the lower housing part 104. A drain device 50 is likewise mounted on the lower end of the fluid line 16, which, during a replacement of the filter element 10, protects the clean side of the tank system from contamination by separating the first 64 and second fluid 66. As in the embodiment of FIG. 1, during replacement of the filter element 10 from the lower housing part 104, the first fluid 64 still located in the raw region on the raw side 60 of the filter system 100 may drain via an emptying channel 54 and may not enter the clean side 62, i.e. the inner region 36 of the filter element 10 and thus the internal combustion engine, by means of the arrangement of the two O-ring seals 46.

(31) FIG. 4 shows an enlarged view of the upper part of the longitudinal section of FIG. 3 with details of the arrangement of the non-return valve 18 for ventilation in the fluid line 16. The non-return valve 18 is embedded with its valve support 32, in which the valve body 30 is arranged, directly in the fluid line 16, for example pressed thereinto, said fluid line being formed in the support tube 24 and being radially sealed with an O-ring seal 34 with respect to the filter element 10. Alternatively, the non-return valve 18 may be arranged in the upper housing part 102 and be fixed there, for example via a snap connection 22. If the upper housing part 102 is then place onto the filter element 10 which is inserted in the lower housing part 104, the non-return valve 18 may thus be pushed into the fluid line 16 formed in the support tube 24 and may be sealed via the O-ring seal 34. The second fluid path 14 for ventilating the filter system 100 thus leads in an analogous manner to the filter system shown in FIG. 1 from the outer region 44 of the filter element 10 via the non-return valve 18, the function of which is represented by a ball 26 which is pressed into a valve seat by means of a spring 28, into the support tube 24 which is formed as a fluid line 16, from where the air can be redirected back into the tank system. The manner of operation of the non-return valve 18 occurs in an analogous manner to the filter system shown in FIG. 1. If an internal combustion engine connected to the filter system 100 is turned off, for example in start/stop operation, and as a result no fuel is resupplied from a tank system, the non-return valve 18 may thus close. The pressure in the filter element 10 is thereby maintained, the fuel remains in the filter system 100. This provides the conditions for a quick start of the internal combustion engine. After re-opening of the non-return valve 18, the ventilation of the filter system 100 again begins to operate.

(32) FIG. 5 shows a longitudinal section through a filter system 100 according to a further embodiment of the invention for fuel filtration in a motor vehicle with two O-rings 46 for sealing a filter element 10 against a filter housing 101. The construction of the filter system 100 is similar to the filter system shown in FIG. 3 with a flow direction from the outside to the inside, which is indicated by arrows from an inner region 44 into an inner region 36 in the filter element 10, i.e. from a raw side 60 to a clean side 62 of the filter system, and differs from the embodiment shown in FIG. 3 in that the receptacle of the filter element is designed differently in the lower housing part 104. The filter element 10 has two O-ring seals 46 of the same diameter which sealingly close an emptying channel 54. During replacement of the filter element 10, i.e. when the filter element 10 is pulled out of the lower housing part 104, the first fluid 64 which is still in the outer region 44 may drain by means of this emptying channel 54, so that it does not enter the clean side 62, i.e. the inner region 36 of the filter element 10 and thus into the internal combustion engine.

(33) As in the embodiment shown in FIG. 1, the filter element 10 is connected via a quick coupling 70 in the form of a snap connection with the upper housing part 102, and can thus be pulled out with the unscrewed upper housing part 102 from the lower housing part 104, for example during a change of the filter element 10 for maintenance.

(34) The other functional behavior of the filter system 100 according to the embodiment shown in FIG. 5 corresponds to the embodiment shown in FIG. 3. Here, too, the fluid line 16 is inserted at the lower end with an O-ring seal 48 into a receptacle 106 of the lower housing part 104. A drain device 50 is likewise mounted on the lower end of the fluid line 16, which, during a replacement of the filter element 10, protects the clean side of the tank system from contamination by separating the first and second fluid.

(35) A water separating device 69 can be seen coaxially to the support tube 24, which comprises a coalescer 74, which is arranged concentrically about the fluid line 16 on a clean side 62 of the filter element 10, as well as an end separator 68, which is arranged concentrically about the fluid line 16 between the coalescer 74 and the fluid line 16. The end separator 68 has a sealing lip 52 on the lower end for connecting to an outlet, via which separated water can be fed into a water collection chamber. The end separator 68 is supported by lying against the support tube 24, which is used for ventilating the filter element 10.

(36) FIG. 6 shows a longitudinal section through a filter element 10 with a water separating function, as can be used in the filter system 100 represented in FIG. 5. The filter element 10, which has a first end plate 20 as an upper closure, is stiffened by means of a central support tube 24, which acts as the fluid line 16. The support tube 24 has an O-ring seal 48 on the lower end for sealing when inserted into a filter housing 101, as well as a drain device 50 for separating the first 64 and second fluid 66 when the filter element 10 is changed and thus removed from the filter housing 101. The sealing of the filter element 10 itself to the filter housing 101 occurs via two O-ring seals 46 of the same diameter, which are used to separate the raw side 60 and the clean side 62 of the filter element 10 during replacement through draining of the first fluid 64 still located on the raw side 60 by means of an emptying channel 54. A water separating device 69 can be seen coaxially to the support tube 24, which comprises a coalescer 74 as well as an end separator 68, which has a sealing lip 52 on the lower end for connecting to an outlet, via which separated water can be separately led into a collection chamber. The end separator 68 is supported by lying against the support tube 24. The end plate 20 carried bayonet elements of a quick coupling 70 for connecting the filter element 10 with the upper housing part 102.

(37) FIG. 7 shows a longitudinal section through a filter element 10 without a water separating function, as can be used in the filter system 100 represented in FIG. 5. The filter element 10 has the same features as the filter element 10 shown in FIG. 6, except for the missing water separating device 69 for water separation, so that reference is made to the figures in question for the sake of avoiding unnecessary repetition.

(38) FIG. 8 shows an isometric representation of a filter element 10 with a quick coupling 70 according to another embodiment of the invention. On the upper end plate 20, the filter element 10 has connecting elements of a quick coupling 70, which are designed in the form of bayonet hooks. With these bayonet hooks, a quick and secure connection can be made to an upper housing part 102, on which the filter element 10 can also be removed from the lower housing part 104 during a replacement of the filter element 10, for example for maintenance purposes. A support tube 24 as a fluid line 16 extends centrally beyond the upper end plate 20 of the filter element 10, said support tube having a seal 34 at its upper edge in the form of a molded seal 72, which is arranged sealingly about the support tube 34. The lower end plate 21, which closes the filter body 11 downward, has a seal 46 at its outer periphery for separating a clean side 62 and a raw side 60 of the filter element 10 during installation in a filter housing 101.

(39) FIG. 9 shows a section through the filter element 10 as shown in FIG. 8. It can be seen in the sectional view that the seal 46 at the lower end plate 21 comprises two individual seals 46 in the form of O-rings, which seal the filter body 11 on its outside and inside, and thus separate the raw side 60 from the clean side 62 of the filter element. The inside of the filter body 11 is supported by a central tube 25, which in turn supports a coalescer 74 of a water separating device 69 on its inside. The separation of the coagulated water drops then occurs at the end separator 68 of the water separating device 69 (see FIG. 11), which is arranged concentrically about the support tube 16 and is connected therewith by means of a stiffening rib 78. The molded seal 72 at the upper end of the support tube 16 can also clearly be seen in the section, which molded seal remains on the filter element 10 during replacement thereof and is thus also exchanged with the filter element 10.

(40) FIG. 10 shows a longitudinal section through a filter element 10 with a water separating function according to a further embodiment of the invention and corresponds to the isometric representation of FIG. 9.

(41) FIG. 11 shows a longitudinal section through a filter system 100 with a water separating function according to a further embodiment of the invention. The construction of the filter system 100 is similar to the filter system shown in FIG. 5 with a flow direction from the outside to the inside, which is indicated by arrows from an inner region 44 into an inner region 36 in the filter element 10, i.e. from a raw side 60 to a clean side 62 of the filter system, and differs from the embodiment shown in FIG. 3 in that the receptacle of the filter element is designed differently in the lower housing part 104.

(42) On its lower end plate 21, the filter element 10 has two O-ring seals 46 which seal the filter body 11 respectively on its outside and inside and thus separate the raw side 60 from the clean side 62. During replacement of the filter element 10, i.e. when the filter element 10 is pulled out of the lower housing part 104, the first fluid 64 which is still in the outer region 44 may drain by means of an emptying channel 54, so that it does not enter the clean side 62, i.e. the inner region 36 of the filter element 10 and thus into the internal combustion engine. The filter element 10 is connected via a quick coupling 70 in the form of a bayonet connection with the upper housing part 102, and can thus be removed from the lower housing part 104 with the upper housing part 102 during replacement of the filter element 10 for maintenance purposes. The non-return valve 18 of the second fluid path 14 is seated in the valve support 32, which is connected in turn via a snap connection 22 with the upper housing part 102. In contrast to the other embodiments illustrated in FIGS. 1, 3, 5, the valve support 32 is bell-shaped and can thus slide over the molded seal 72, so as to seal the second fluid path 14 of the fluid line 16, which is formed in the support tube 24. When changing the filter element 10, this can be pulled out with the upper housing part 102. Here, the valve support 32 remains with the non-return valve 18 on the molded seal 72. When the filter element 10 is completely removed from the lower housing part 104, the upper housing part 102 can be removed via the quick coupling 70 with the valve support 32 and the non-return valve 18 arranged therein can be withdrawn from the filter element 10. Here, the valve support 32 is also withdrawn from the molded seal 72, which remains in this case on the support tube 24. When a new filter element 10 is inserted, a new molded seal 72 is thus also used.

(43) The other functional behavior of the filter system 100 according to the embodiment shown in FIG. 5 corresponds to the embodiment shown in FIG. 5. Here, too, the fluid line 16 is inserted at the lower end with an O-ring seal 48 into a receptacle 106 of the lower housing part 104. A drain device 50 is likewise mounted on the lower end of the fluid line 16, which, during a replacement of the filter element 10, protects the clean side of the tank system from contamination by separating the first and second fluid.

(44) A water separating device 69 can be seen coaxially to the support tube 24, which comprises a coalescer 74, which is arranged concentrically about the fluid line 16 on a clean side 62 of the filter element 10, as well as an end separator 68, which is arranged concentrically about the fluid line 16 between the coalescer 74 and the fluid line 16. The end separator 68 is supported via the stiffening element 78 by lying against the support tube 24, which is used for ventilating the filter element 10. The separated water passes through a water drain 114 into a water collection chamber 112, from where it can be discharged via an outlet 116.

(45) The clean side 62 of the filter element 10 opens into an outlet 108, from where the filtered fluid 64 can be conducted into an internal combustion engine. The fluid line 16 opens into an outlet 110, which can be fed back into a tank space.

(46) FIG. 12 shows a longitudinal section through a filter system 100 according to a further embodiment for fuel filtration in a motor vehicle with an arrangement of a non-return valve 18 on a housing cover 102. In general, the functional behavior of the filter system 100 according to the embodiment shown in FIG. 12 corresponds to the embodiments shown in the preceding figures. A replaceable filter element 10 is arranged in the housing 101 of the filter system 100. A first fluid path 12 shows the route of the first fluid 64 to be filtered, for example fuel, from an outer region 44 of the filter element 10 (raw side 60) radially through a filter body 11 of the filter element 10 into an inner region 36 (clean side 62). The non-return valve 18 is arranged above the filter body 11 of the filter element 10 and is fixed on the housing cover 102 by means of a snap connection 22. The non-return valve 18 has a receptacle 121 for an element-side non-return valve port 122. The second fluid path 14 for ventilating the filter system 100 leads from the outer region 44 of the filter element 10 through the non-return valve 18 into the fluid line 16 fixed to the element, which opens into an outlet 40 in the form of a housing-side outflow channel. In particular, the manner of function of the non-return valve 18 corresponds to that of the already-described embodiments.

(47) The fluid line 16 is part of the replaceable filter element 10. It extends from the end face of the filter element 10, which is arranged above in the installed state, to the opposite, lower end face through the inner region 36 surrounded by the filter body 11.

(48) The filter body 11 has a star-folded filter media web, which is used for particle filtration. A wound coalescer 74 is likewise provided within the star-folded filter media web. A water separating element 68, for example with a hydrophobic mesh fabric, in turn follows the coalescer 74 in the direction of flow, which water separating element is however arranged for example within the coalescer 74 and at the height thereof. An annular water discharge gap 126 is formed between the coalescer medium 74 and the water separating element 68. The annular water discharge gap 126 is connected below with a water collection area 112 of the filter system 100. The inner region 36 surrounded by the water separating element 68 is provided on the lower end face with a clean fuel outlet 128.

(49) In FIG. 13, the filter element 10 of the filter system 100 according to FIG. 12 is shown in isolation. The non-return valve port 122 is formed as a stub-shaped protrusion of the fluid line 16, which protrudes on the upper end face of the filter element 10 and is arranged coaxially to the longitudinal element axis 129. It is provided with a seal oriented radially outward in the form of an applied O-ring 34 for sealing against the non-return valve 18.

(50) The filter element 10 comprises an outflow port 131 on the lower end face, by means of which the fluid line 16 can be connected to the discharge 110 during installation of the filter element 10 in the housing 101 of the filter system 100. The outflow port 131 is also designed as a stub-shaped protrusion of the fluid line 16, which is arranged coaxially to the longitudinal element axis 129. It has a circumferential seal which is oriented radially outward in the form of an applied O-ring 48. A drain device 50 is likewise mounted on the lower end of the fluid line 16, which, during a replacement of the filter element 10, protects the clean side 62 of the tank system from contamination by separating the first 64 and second fluid 66.

(51) In addition, the filter element 10 has two circumferential seals 133, 134 on the lower end face, wherein the seal 133 is oriented radially outward and the seal 134 is oriented radially inward. The seal 133 abuts against the inner housing wall and is used for sealing the outer annular space 44 from an emptying area 54 formed as a groove (FIG. 12). The other seal 134 abuts against a housing stub 136 and is used for sealing the water collection area 127 against the emptying area 135. The element-side clean fuel outlet 128 is surrounded by a stub-shaped protrusion 137, which additionally surrounds the outflow pot 131 and is mounted on a housing-side stub 138, which encloses an annular channel of the fuel outlet 108.

(52) FIG. 14 shows a longitudinal section through a filter system 100 according to a further embodiment of the invention for fuel filtration in a motor vehicle with an arrangement of a non-return valve 18 in the fluid line 16 fixed to the element. The fluid line 16 is formed in this example from a section 141 provided through the end plate 20 of the filter element 10 and a section 142 extending in the inner region of the filter media body 119. As in the example according to FIG. 12, the fluid line 16 is exchanged together with the filter element 10, wherein at the same time the non-return valve 18 integrated in section 141 is also exchanged. The filter system 100 according to FIG. 14 is similar to the other embodiments in construction and function, so that reference is made in general to the preceding descriptions, wherein advantageous differences also arise from FIG. 14.