Filter for Filtering Fluid, Bypass Valve Arrangement for a Filter, and Diffuser Device for a Filter

Abstract

A filter for filtering fluid has a filter housing with fluid inlet for fluid to be filtered and fluid outlet for filtered fluid. A filter element arranged in the filter housing separates fluid inlet fluidically from fluid outlet. A bypass valve arrangement is arranged fluidically between fluid inlet and fluid outlet such that it fluidically connects in an open state fluid inlet to fluid outlet. The bypass valve arrangement has a valve closure body arranged movably in the valve housing between a closed position and an open position. The bypass valve arrangement has a valve seat element with valve seat. The valve closure body rests sealingly at the valve seat in closed position. The valve seat element is connected to a part of the valve housing by a mechanical connection realized by relative rotation between valve seat element and part of the valve housing about a valve axis.

Claims

1. A filter for filtering fluid, the filter comprising: a filter housing comprising a fluid inlet for fluid to be filtered and a fluid outlet for filtered fluid; a filter element arranged in the filter housing such that the filter element separates the fluid inlet fluidically from the fluid outlet; a bypass valve arrangement arranged fluidically between the fluid inlet and the fluid outlet such that the bypass valve arrangement, in an open state thereof, connects the fluid inlet fluidically to the fluid outlet; wherein the bypass valve arrangement comprises a valve housing; wherein the bypass valve arrangement comprises a valve closure body arranged in the valve housing and movable between a closed position and an open position; wherein the bypass valve arrangement further comprises a valve seat element comprising a valve seat, wherein the valve closure body is configured to rest sealingly at the valve seat in the closed position; wherein the valve seat element is connected by a mechanical connection to a part of the valve housing, wherein the mechanical connection is configured to be realized by a relative rotation between the valve seat element and the part of the valve housing about a valve axis of the bypass valve arrangement.

2. The filter according to claim 1, wherein the mechanical connection between the valve seat element and the part of the valve housing is a screw connection.

3. The filter according to claim 2, wherein the valve seat element comprises an outer thread and the part of the valve housing comprises an inner thread for forming the screw connection, or wherein the valve seat element comprises an inner thread and the part of the valve housing comprises an outer thread for forming the screw connection.

4. The filter according to claim 2, wherein a thread of the valve seat element and a thread of the part of the housing form the screw connection, wherein the thread of the valve seat element and/or the thread of the part of the housing is a non-self-tapping thread.

5. The filter according to claim 2, wherein a thread of the valve seat element and a thread of the part of the housing form the screw connection, wherein the thread of the valve seat element or the thread of the part of the housing is a self-tapping thread.

6. The filter according to claim 1, wherein the valve housing comprises a valve seal section acting at least radially in relation to the valve axis of the bypass valve arrangement.

7. The filter according to claim 1, wherein the valve housing comprises a valve seal section interacting sealingly with an element seal section of the filter element.

8. The filter according to claim 1, wherein the valve seat element comprises a housing fastening element connecting the valve seat element to a part of the filter housing.

9. The filter according to claim 1, wherein the valve seat element comprises an operating section configured to operate the valve seat element when connecting the valve seat element to the valve housing.

10. The filter according to claim 1, wherein the bypass valve arrangement comprises a valve return element engaging with a first end the valve closure body and with a second end the valve housing.

11. The filter according to claim 1, wherein the valve seat element and/or the part of the valve housing comprises a seal device configured to seal a region between the valve seat element and the part of the valve housing.

12. The filter according to claim 1, wherein the filter is an in-tank filter and/or the filter is a liquid filter and/or a gas filter.

13. The filter according to claim 1, wherein the valve seat element is a hollow cylinder comprising an inner thread and/or an outer thread.

14. The filter according to claim 1, further comprising at least one diffuser device connected to the fluid outlet.

15. A bypass valve arrangement for a filter for filtering fluid, the bypass valve arrangement comprising: a valve housing; a valve closure body arranged in the valve housing and movable between a closed position and an open position; a valve seat element comprising a valve seat, wherein the valve closure body is configured to rest sealingly at the valve seat in the closed position; wherein the valve seat element is connected by a mechanical connection to a part of the valve housing, wherein the mechanical connection is configured to be realized by a relative rotation between the valve seat element and the part of the valve housing about a valve axis of the bypass valve arrangement; wherein the bypass valve arrangement is configured to be arranged fluidically between a fluid inlet and a fluid outlet of the filter such that the bypass valve arrangement, in an open state thereof, fluidically connects the fluid inlet to the fluid outlet.

16. A filter element assembly for a filter for filtering fluid, the filter element assembly comprising: a filter element comprising a receptacle; a bypass valve arrangement received in the receptacle, wherein the bypass valve arrangement is attached to an end body of the filter element such that the bypass valve arrangement, in an open state thereof, fluidically connects a raw fluid side of the filter element to a clean fluid side of the filter element; wherein the bypass valve arrangement comprises a valve closure body movable between a closed position and an open position; wherein the bypass valve arrangement further comprises a valve seat, wherein the valve closure body is configured to rest sealingly at the valve seat in the closed position.

17. A filter for filtering fluid, the filter comprising: a filter housing comprising a fluid inlet for fluid to be filtered and a fluid outlet for filtered fluid: a filter element arranged in the filter housing fluidically between the fluid inlet and the fluid outlet; a diffuser device for the filtered fluid, wherein the diffuser device is fluidically connected to the fluid outlet; wherein the diffuser device comprises fluid guiding surfaces.

18. The filter according to claim 17, wherein the diffuser device comprises a fluid guiding channel.

19. The filter according to claim 18, wherein the fluid guiding channel is delimited by at least one of the fluid guiding surfaces.

20. The filter according to claim 18, wherein a channel axis of the fluid guiding channel extends at an angle between approximately 90° and 180° in relation to a main inflow axis of the diffuser device.

21. The filter according to claim 18, wherein the fluid guiding channel comprises at least in sections a constant cross section and/or the fluid guiding channel widens at least in sections, viewed in a fluid flow direction of the filtered fluid.

22. The filter according to claim 17, wherein at least two of the fluid guiding surfaces at least in sections extend parallel to each other.

23. The filter according to claim 17, wherein at least two of the fluid guiding surfaces at least in sections extend away from each other, viewed in a fluid flow direction of the filtered fluid.

24. The filter according to claim 17, wherein at least one of the fluid guiding surfaces at least in sections is positioned at an angle between approximately 90° and 180° in relation to a main inflow axis of the diffuser device.

25. The filter according to claim 17, wherein at least two of the fluid guiding surfaces are arranged on different sides in relation to a main inflow axis of the diffuser device.

26. The filter according to claim 17, wherein at least two of the fluid guiding surfaces are arranged on the same side in relation to a main inflow axis of the diffuser device.

27. The filter according to claim 17, wherein the diffuser device further comprises at least two fluid guiding channels arranged on different sides of the diffuser device in relation to a main inflow axis of the diffuser device.

28. The filter according to claim 17, wherein the diffuser device further comprises at least two fluid guiding channels arranged on the same side of the diffuser device in relation to a main inflow axis of the diffuser device.

29. The filter according to claim 17, wherein at least one of the fluid guiding surfaces, at least in sections, extends curved and/or straight.

30. The filter according to claim 17, wherein the diffuser device further comprises at least one fluid guiding channel that, at least in sections, extends curved and/or straight

31. The filter according to claim 17, wherein the diffuser device further comprises at least one fluid guiding channel that, at least in sections, extends spirally and/or helically.

32. The filter according to claim 17, wherein the diffuser device further comprises a diffuser connection section configured to be connected to the fluid outlet of the filter housing.

33. The filter according to claim 17, wherein the diffuser device further comprises at least one connection seal element configured to seal the diffuser device relative to the fluid outlet of the filter housing.

34. The filter according to claim 17, wherein the diffuser device further comprises at least one diffuser fixation element configured to fix the diffuser device at the filter housing.

35. The filter according to claim 17, wherein the diffuser device further comprises a diffuser inlet channel connected to at least one fluid guiding channel of the diffuser device and/or extending to at least one of the fluid guiding surfaces.

36. The filter according to claim 35, wherein a main inflow axis of the diffuser device extends within the diffuser inlet channel of the diffuser device.

37. The filter according to claim 35, wherein the diffuser inlet channel, at least in sections, comprises a round cross section and/or a constant cross section.

38. A diffuser device for a filter for filtering fluid, the diffuser device comprising a diffuser connection section configured to fluidically connect the diffuser device to a fluid outlet of a filter housing of the filter, wherein the diffuser device comprises fluid guiding surfaces.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0119] Further advantages, features, and details of the invention result from the following description in which embodiments of the invention will be explained in no more detail with the aid of the drawing. A person of skill in the art will consider the features disclosed in combination in the drawing, the description, and the claims expediently also individually and combine them to expedient further combinations. The drawings show schematically embodiments of the invention.

[0120] FIG. 1 shows a longitudinal section of a tank for liquid in which a filter according to a first embodiment with a bypass valve arrangement according to a first embodiment and a diffuser device according to a first embodiment is arranged.

[0121] FIG. 2 shows a longitudinal section of the filter of FIG. 1.

[0122] FIG. 3 shows an isometric view of the filter of FIGS. 1 and 2.

[0123] FIG. 4 shows an isometric detail view of the diffuser device of the filter of FIGS. 1 to 3.

[0124] FIG. 5 shows a longitudinal section of the diffuser device of the filter of FIGS. 1 to 3.

[0125] FIG. 6 shows a detail view of the longitudinal section of the filter of FIG. 2 in the region of the connection of the bypass valve arrangement in a top end cap of a filter element of the filter.

[0126] FIG. 7 shows an isometric view of the bypass valve arrangement according to the first embodiment of the filter of FIGS. 1 to 3.

[0127] FIG. 8 shows a longitudinal section of the bypass valve arrangement according to the first embodiment of the filter of FIGS. 1 to 3.

[0128] FIG. 9 shows an isometric illustration of a filter arrangement with two filters according to the first embodiment of FIGS. 1 to 3.

[0129] FIG. 10 shows an isometric illustration of a filter arrangement with two filters according to a second embodiment.

[0130] FIG. 11 shows a longitudinal section of the filter arrangement of FIG. 10.

[0131] FIG. 12 shows an isometric illustration of a bypass valve arrangement according to a second embodiment.

[0132] FIG. 13 shows a longitudinal section of the bypass valve arrangement according to the second embodiment of FIG. 12.

[0133] FIG. 14 shows an isometric illustration of a diffuser device according to a second embodiment.

[0134] FIG. 15 shows a longitudinal section of the diffuser device according to the second embodiment of FIG. 14.

[0135] FIG. 16 shows a cross section of the diffuser device according to the second embodiment of FIGS. 14 and 15 along a section line XVI-XVI of FIG. 15.

[0136] In the Figures, same components are provided with same reference characters.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0137] In FIG. 1, a tank 10 for liquid, for example, fuel, oil, hydraulic oil, urea-water solution or the like, is illustrated. In the tank 10, a filter 12 in the form of a liquid filter as a so-called in-tank filter according to a first embodiment is arranged. The filter 12 is inserted into a top wall of the tank 10 and extends into the interior of the tank 10. Outside of the tank 10, the filter 12 is accessible from the exterior.

[0138] The filter 12 and its components are illustrated in FIGS. 2 to 8 in different perspectives, section views, and detail illustrations.

[0139] The filter 12 comprises a filter housing 14 in which a filter element 16 and a bypass valve arrangement 18 according to a first embodiment are arranged. Moreover, the filter 12 comprises a diffuser device 20 in the first embodiment. The diffuser device 20 is illustrated in detail in FIGS. 4 and 5. The bypass valve arrangement 18 is illustrated in detail in FIGS. 7 and 8. The connection of the bypass valve arrangement 18 to the filter element 16 is illustrated in detail in FIG. 6.

[0140] The filter housing 14 comprises a housing pot 22, in FIGS. 1 to 3 at the bottom, a housing connection part 24 at the center, and a housing cover 26 at the top. The housing pot 22 has approximately the shape of a hollow circular cylinder coaxial to an imaginary filter axis 28.

[0141] The filter axis 28 coincides in the embodiment with a valve axis 128 of the bypass valve arrangement 18 and a diffuser main flow axis 204 of the diffuser device 20. When in the following “radial”, “coaxial”, “axial”, “tangential”, “circumferential”, “concentric”, “eccentric” or the like is mentioned, this relates to the axis corresponding to the context, if nothing to the contrary is mentioned.

[0142] On an axial end face, in FIGS. 1 to 3 at the bottom, the housing pot 22 comprises a bottom section in which an exemplary coaxial fluid outlet 30 is located. On the oppositely positioned axial end face, at the top, the housing pot 22 comprises an installation opening 32 for the filter element 16.

[0143] The fluid outlet 30 comprises an exemplary coaxial circular cylinder outlet socket 34 which has a hollow interior. The outlet socket 34 has a smaller diameter than the housing pot 22. The outlet socket 34 extends in axial direction through the bottom of the housing pot 22. Viewed axially, the outlet socket 34 extends approximately with one half into the interior of the housing pot 22 and with the other half outside of the housing pot 22.

[0144] The portion of the outlet socket 34 which is located outside of the housing pot 22 is configured as a connection part 36 for the diffuser device 20. The connection part 36 comprises a circumferential locking collar 38. Viewed from the locking collar 38 toward the free end of the connection part 36, the outer diameter of the connection part 36 tapers conically. In front of the free end of the connection part 36, a seal receptacle 40 extends continuously circumferentially. In the seal receptacle 40, a seal ring 42 is arranged. The seal ring 42 is acting sealingly in radial direction.

[0145] The installation opening 32 of the housing pot 22 extends radially across the entire inner cross section of the housing pot 22. In the region of the end face rim which surrounds the installation opening 32, the housing pot 22 has a shoulder 44. The shoulder 44 extends at the radially outer circumferential side circumferentially and radially outwardly. In the radially outer circumferential side of the shoulder 44, two seal receptacles 46 are arranged. The seal receptacles 46 each extend circumferentially continuously. Viewed in axial direction, the seal receptacles 46 are arranged adjacent to each other. In each seal receptacle 46, a seal ring 48 is arranged. The seal rings 48 each are acting sealingly in radial direction.

[0146] At the end of the outlet socket 34 which is located in the interior of the housing pot 22, an exemplary coaxial central tube 50 is attached. Viewed from the outlet socket 34, the central tube 50 tapers toward its free end. At its free end, the central tube 50 comprises a coaxial rod-shaped attachment 52. The circumferential wall of the central tube 50 is permeable for fluid. In an exemplary fashion, the central tube 50 is inserted with one end into the outlet socket 34.

[0147] The housing connection part 24 comprises approximately the shape of a hollow circular cylinder which is open at both axial ends. The housing connection part 24 is coaxial to the filter axis 28. The housing connection part 24 comprises a fluid inlet 54 and a mounting flange 62. The fluid inlet 54 comprises an inlet socket 58 which surrounds an inlet channel 60. The inlet socket 58 extends radially outwardly on a circumferential side of the housing connection part 24. A connection flange 56 is arranged at the free end of the inlet socket 58. The connection flange 56 comprises in an exemplary fashion four screw openings at which a corresponding pipe conduit socket of a fluid supply line, not illustrated, can be detachably fastened. The housing connection part 24 is realized with the mounting flange 62 and the inlet socket 58 in a one-piece configuration.

[0148] At an axial end face rim, in FIGS. 1 to 3 at the bottom, that is facing the housing pot 22 in the mounted state, the housing connection part 24 comprises a stop web 64 at the radially inner circumferential side. The stop web 64 extends radially inwardly. An inner diameter in the region of the stop web 64 is smaller than an outer diameter of the shoulder 44 of the housing pot 22. Also, the inner diameter of the stop web 64 is larger than the outer diameter of the housing pot 22 outside of the shoulder 44. The inner diameter of the housing connection part 24 in axial direction adjacent to the stop web 64 is somewhat larger than the outer diameter of the shoulder 44 of the housing pot 22.

[0149] For mounting, the housing pot 22, with its bottom end provided with the fluid outlet 30 leading, can be inserted in axial direction through the opening at the end of the housing part 24 which is axially facing away from the stop web 64. In the mounted state, the stop web 64, as illustrated in FIGS. 2 and 6, is contacting the shoulder 44 in axial direction. The seal rings 48 are sealingly contacting radially the radially inner circumferential side of the housing connection part 24 which acts as a seal surface.

[0150] The mounting flange 62 of the housing connection part 24 is located between the inlet socket 58 and the free rim with the stop web 64. The mounting flange 62 extends circumferentially at the radially outer circumferential side of the housing connection part 24. The mounting flange 62 comprises, circumferentially distributed, four screw holes 66, for example. The axes of the screw holes 66 extend parallel to the filter axis 28. At its axial end face facing the rim of the housing connection part 24 with the stop web 64, the mounting flange 62 comprises a seal receptacle 68. A seal ring 70 is arranged in the seal receptacle 68.

[0151] When the filter 12 is mounted in tank 10, the mounting flange 62 is resting on a corresponding tank mounting section 72 of the tank 10. The mounting flange 62 is screwed with four screws to the tank mounting section 72. The seal ring 70 is positioned, acting sealingly in axial direction, on a corresponding seal surface of the tank mounting section 72.

[0152] Between the inlet 58 and the free rim which is positioned opposite the stop web 64, the housing connection part 24 comprises an inner thread 74 at its radially inner circumferential side. Between the inner thread 74 and the free rim of the axial end face of the housing connection part 24, the radially inner circumferential side of the housing connection part 24 is designed as a seal surface 76. Toward the axial free rim, the seal surface widens approximately in a funnel shape and forms thus an insertion ramp for the housing cover 26.

[0153] The housing cover 26 comprises a coaxial circular cylindrical circumferential wall. On an axial end face which is facing the housing pot 22 in the mounted state, the housing cover 26 is open. The housing cover 26 is closed at the axially oppositely positioned end face.

[0154] Axially adjacent to the open rim, the housing cover 26 comprises at its radially outer circumferential side an outer thread 78. The outer thread 78 matches the inner thread 74 of the housing connection part 24. In the mounted state, the outer thread 78 is screwed into the inner thread 74.

[0155] At the side axially opposite the free rim, a circumferentially continuous seal receptacle 80 is arranged adjacent to the outer thread 78 in the radially outer circumferential side of the housing cover 26. In the seal receptacle 80, a seal ring 82 is arranged. With mounted housing cover 26, the seal ring 82, acting sealingly in radial direction, is resting against the seal surface 76 of the housing connection part 24.

[0156] At the side of the seal receptacle 80 that is axially opposite the outer thread 78, a stop web 84 is realized. The stop web 84 extends at the radially outer circumferential side of the housing cover 26 radially outwardly. In the mounted state of the housing cover 26, the free rim of the housing connection part 24 is resting against the stop web 84. In this way, it can be prevented that the housing cover 26 is screwed in too far into the housing connection part 24.

[0157] On its closed side, the housing cover 26 is provided externally with an engagement element 86. The engagement element 86 is configured in an exemplary fashion in the form of a hexagon and coaxial to the filter axis 28. For example, a tool, for example, a wrench, can be engaged with the engagement element 86 in order to screw the housing cover 26 into the housing connection part 24 or to unscrew it therefrom.

[0158] In the interior of the housing cover 26, a coaxial holding basket 88 is arranged. The holding basket 88 has approximately the shape of a coaxial hollow circular cylinder. The holding basket 88 is connected to the closed side of the housing cover 26 in a one-piece configuration.

[0159] The holding basket 88 comprises at the free end a coaxial circumferentially continuous annular stay 94 and a plurality of basket stays 90. The basket stays 90 each extend approximately parallel to the filter axis 28 between the annular stay 94 and the closed side of the housing cover 26. Through openings 92 for fluid are realized between the basket stays 90.

[0160] The radially inner circumferential side of the annular stay 94 forms a circumferentially continuous locking projection 96. At its side which is axially facing the housing pot 22, the locking projection 96 comprises an insertion ramp for a housing fastening element 178 of the bypass valve arrangement 18. The holding basket 88 projects in axial direction past the free rim of the circumferential wall of the housing connection part 24.

[0161] The filter element 16 is designed in an exemplary fashion as a round filter element. The filter element 16 comprises a filter medium 98, for example, in the form of filter nonwoven or the like, which coaxially surrounds a coaxial support basket 100. The filter medium 98 and the support basket 100 surround an element interior 102 of the filter element 16.

[0162] At an end face which is axially facing the fluid outlet 30, the filter element 16 comprises an outlet-side end cap 104. The outlet-side end cap 104 extends in radial direction past the axial end face of the filter medium 98. At the center, the outlet-side end cap 104 comprises an insertion opening. Through the insertion opening, the central tube 50 and the inner part of the connection socket 34 project into the element interior 102.

[0163] At the radially outer circumferential side, the end cap 104 comprises a wall section extending in axial direction and in circumferential direction and surrounding the filter medium 98. At the radially inner circumferential side, the outlet-side end cap 104 is stepped forming a seal receptacle in which a seal ring 106, for example, of elastomer, is arranged. When the filter element 16 is installed, the seal ring 106 is resting at the radially outer circumferential side of the outlet socket 34, which forms a seal surface, so as to seal in radial direction.

[0164] At the end face which is axially facing the housing cover 26, the filter element 16 comprises an inlet-side end cap 108. The inlet-side end cap 108 comprises a flat base section 110 extending in radial direction and a radially outer cylindrical flow protection section 112 which is extending away from the radially outer rim of the base section 110 in the direction toward the outlet-side end cap 104. The axial length of the flow protection section 112 is designed such that the filter medium 98 is protected from a direct radial flow of fluid entering the filter housing 14 through the fluid inlet 54.

[0165] The inlet-side end cap 108 comprises a coaxial seal cylinder section 114 at the radially inner circumferential side. The seal cylinder section 114 extends in axial direction away from the flow protection section 112. In its radially inner circumferential side, the seal cylinder section 114 comprises a seal receptacle 116 in which a seal ring 118, for example, in form of an O-ring, is arranged. The seal ring 118 can be of elastomer, for example. In addition or as an alternative to the seal ring 118, the seal can also be provided by the material of the end cap 108. A seal which is acting sealingly in axial direction or axial and radial direction can be provided also.

[0166] The bypass valve arrangement 18 according to the first embodiment is shown in detail in FIGS. 7 and 8. The bypass valve arrangement 18 comprises a valve housing 120, a valve closure body 122, a valve return element 124, in an exemplary fashion in form of a coaxial coil pressure spring, and a valve seat element 126.

[0167] The valve closure body 122 is arranged axially movable relative to the valve axis 128 in the valve housing 120. The valve closure body 122 comprises a valve plate 130 and a valve rod 132. The valve plate 130 and the valve rod 132 are embodied as one piece in an exemplary embodiment.

[0168] The valve rod 132 has the shape of a hollow circular cylinder.

[0169] The valve plate 130 is arranged at an axial end of the valve rod 132 and closes there the interior of the valve rod 132. The valve plate 130 is bent at its radially outer rim toward the free end of the valve rod 132. The thus formed radially outer circumferential side of the valve plate 130 has a coaxial circular cylindrical extension and forms a guide section 135. The interior of the valve rod 132 is open at the free end.

[0170] The bent rim of the valve plate 130 forms a valve seat contact surface 133 in the region of the bend. In the closed position which is illustrated in FIGS. 1, 2, and 6 to 8, the valve seat contact surface 133 is seal-tightly resting against a valve seat 134 of the valve seat element 126. The valve plate 130 and the valve seat 134 each have as a whole a shape of rotational symmetry relative to the valve axis 128.

[0171] The valve plate 130 comprises at its axial outer side a coaxial sleeve. The outer diameter of the sleeve corresponds approximately to the inner diameter of the interior of the valve rod 132.

[0172] The valve housing 120 is configured as a valve basket or valve cage. The valve housing 120 comprises a coaxial circumferential wall. The circumferential wall comprises a plurality of flow-through openings 164 for fluid. The circumferential wall is stepped multiple times in axial direction. At an axial top side in FIGS. 7 and 8, the valve housing 120 has an installation opening 136 for the valve seat element 126. At the axial bottom side, the valve housing 120 is closed by a bottom section 146.

[0173] At the side which is facing the bottom section 146, the valve housing 120 has at the radially outer circumferential side several wings 138 which extend radially outwardly, respectively. The wings 138 are connected to the bottom section 146 in a one-piece configuration. The wings 138 end with an axial end face at the same level as the bottom side of the bottom section 146, respectively. The end faces of the wings 138 facing axially away from the bottom side of the bottom section 146 are located at axially different levels, viewed in axial direction. The end faces of the wings 138 facing axially away from the bottom side of the bottom section 146 extends along an imaginary coaxial helical line. The wings 138 can be joined, for example, with corresponding parts of the support basket 100 of the filter element 16 to a bayonet closure-type connection.

[0174] In the interior of the valve housing 120, a guide cylinder 140 extends from the bottom section 146 coaxially into a coaxial receiving space 142 for the valve return element 124. The guide cylinder 140 is connected the bottom section 146 in a one-piece configuration.

[0175] At the side of the bottom section 146 which is facing the interior of the valve housing 120, a circumferentially continuous coaxial annular guide groove 144 is arranged. The annular guide groove 144 surrounds the guide cylinder 140.

[0176] The valve rod 132 of the valve closure body 122 is positioned movably in axial direction on the guide cylinder 140. The guide cylinder 140 and the annular guide groove 144 guide the valve rod 132 during its axial movements.

[0177] The valve rod 132 comprises at its open end radially outwardly a guide ramp 150. By means of the guide ramp 150, the valve rod 132 can be inserted more easily into the annular guide groove 144 during its axial movement.

[0178] Radially outwardly of the annular guide groove 144, the bottom section 146 forms a support section 148 which extends in radial direction and circumferentially. At the support section 148, the valve return element 124, namely the coil spring, is supported with one end. With the other end, the valve return element 124 is supported at the bottom side of the valve plate 130. The valve return element 124 acts on the valve plate 130 and pushes the valve plate 130 against the valve seat 134.

[0179] The bottom section 146 passes into a circumferential receiving wall section 152 in a one-piece configuration. The receiving wall section 152 surrounds coaxially the receiving space 142 for the bottom part of the valve return element 124 which is facing the bottom section 146. The inner diameter of the receiving space 142 is somewhat larger than the outer diameter of the valve return element 124.

[0180] Behind a step in radially outward direction, the receiving wall section 152 passes into a circumferential guide space wall section 156 in a one-piece configuration. The guide space wall section 156 surrounds a coaxial guide space 158 for the valve plate 130. The receiving wall section 152 and the guide space wall section 156 are each realized by axially extending wall stays 160. The wall stays 160 extend respectively between two coaxial annular sections 162, which are spaced apart in axial direction. The central annular section 162 is positioned at the level of the step between the receiving wall section 152 and the guide space wall section 156. Between the wall stays 160, continuous flow-through openings 146 for fluid are realized, respectively. The receiving wall section 152 and the guide space wall section 156 are permeable for fluid.

[0181] In the region of the central annular section 162, the wall stays 160 of the receiving wall section 152 and the wall stays 160 of the guide space wall section 156 overlap in axial direction.

[0182] The wall stays 160 of the receiving wall section 152 comprise at their ends facing away from the bottom section 146 a respective insertion ramp 166 at the radial inner circumferential side. The insertion ramps 166 facilitate installation of the valve return element 124.

[0183] Above the wall stays 160 of the receiving wall section 152, the radially inner circumferential sides of the wall stays 160 of the guide space wall section 156 extend in axial direction. The radially inner circumferential side of the wall stays 160 of the guide space wall section 156 form radially outer guide surfaces 168. At the guide surface 168, the guide section 135 of the valve plate 130 is guided upon a movement of the valve closure body 122 in axial direction.

[0184] At the side which is axially facing away from the bottom section 146, the top annular section 162 of the guide space wall section 156 passes into a screwing and sealing section 170 in a one-piece configuration.

[0185] The radially outer circumferential side of the screwing and sealing section 170 forms a seal surface 172. The seal surface 172 has the shape of a coaxial circular cylinder wall. With the bypass valve arrangement 18 installed, the seal rings 118 of the inlet-side end cap 108 of the filter element 16 rest in radial direction seal-tightly at the seal surface 172.

[0186] The radially inner circumferential side of the screwing and sealing section 170 comprises a coaxial valve housing thread 174 in the form of an inner thread.

[0187] At the side facing axially away from the bottom section 146, the screwing and sealing section 170 passes in a one-piece configuration into a fastening flange 176 which extends circumferentially and radially outwardly.

[0188] The fastening flange 176 comprises at its side which is axially facing away from the bottom section 146 a one-piece housing fastening element 178. The housing fastening element 178 comprises a coaxial circumferentially continuous locking ring 180. The locking ring 180 is connected with a plurality of fastening stays 182 to the fastening flange 176 in a one-piece configuration. The fastening stays 182 extend respectively in axial direction and are arranged distributed in circumferential direction. When the filter 12 is mounted, the locking ring 180 locks behind the locking projection 96 of the holding basket 88 of the housing cover 26. With the housing fastening element 178 and the locking projection 96, the bypass valve arrangement 18 is held at the housing cover 26.

[0189] Radially within the housing fastening element 178, a coaxial seal cylinder section 184 is arranged. The seal cylinder section 184 is connected to the side of the fastening flange 176 which is facing away from the bottom section 146 in a one-piece configuration. The radially outer circumferential side of the seal cylinder section 184 is spaced apart relative to the radially inner circumferential side of the housing fastening element 178. The inner diameter of the seal cylinder section 184 is larger than the inner diameter of the screwing and sealing section 170. The radially inner circumferential side of the seal cylinder section 184 is configured as seal surface 186. At its rim which is facing axially away from the bottom section 146, the seal cylinder section 184 has an insertion ramp 188 at the radially inner circumferential side. The insertion ramp 188 facilitates the installation of the valve seat element 126 in the valve housing 120.

[0190] The valve seat element 126 has as a whole the shape of a stepped hollow circular cylinder which is arranged coaxially. At the side which is axially facing the bottom section 146 of the valve housing 120, the valve seat element 126 has a coaxial thread wall section 190 which is extending circumferentially and axially. The thread wall section 190 comprises at its radially outer circumferential side a valve seat element thread 192 in the form of an outer thread. The valve seat element thread 192 in the mounted state is screwed into the valve housing thread 174 and forms therewith a screw connection. The screw connection can be realized by means of a relative rotation between the valve seat element 126 and the screwing and sealing section 170 of the valve housing 120 and separated in opposite rotational direction.

[0191] The free rim of the thread wall section 190 which is facing the bottom section 146 is slanted at the radial inner circumferential side and forms thereat the valve seat 134.

[0192] The inner diameter of the thread wall section 190 is smaller than the outer diameter of the valve plate 130. In the closed state of the bypass valve arrangement 18 illustrated in FIG. 8, the radially outer circumferential side of the valve plate 130 rests under the spring force of the valve return element 124 seal-tightly at the valve seat 134.

[0193] Behind a step in radially outward direction, the thread wall section 190 passes into the operating and sealing wall section 194 in a one-piece configuration. The operating and sealing wall section 194 comprises at the radially outer circumferential side a plurality of sealing knobs 196 which extend circumferentially continuously and radially outwardly.

[0194] The outer diameter of the operating and sealing wall section 194 is somewhat smaller than the inner diameter of the seal cylinder wall section 184 of the valve housing 120. With mounted valve seat element 126, the sealing knobs 196 are resting, sealing in radial direction, at the radially inner circumferential side of the seal cylinder wall section 184.

[0195] The radially inner circumferential side of the operating and sealing wall section 194 is designed as an operating element 198. The operating element 198 comprises in an exemplary fashion the shape of a hexagon socket opening. With an appropriate tool, for example, a hexagon socket wrench, it is possible to engage the operating element 198. By operating with the tool, the valve seat element 126 can be screwed into the screwing and sealing section 170 of the valve housing 120 or can be unscrewed therefrom. Moreover, the pre-mounted bypass valve arrangement 18 can be inserted into the installation opening in the inlet-side end cap 108 by operating with the tool.

[0196] With mounted bypass valve arrangement 18, the interior of the valve seat element 126 is fluidically connected via the through openings 92 of the holding basket 88 to the fluid inlet 54. In this manner, the fluid pressure of the raw fluid side of the filter element 16 is applied. The interior of the valve housing 120 is connected via the through openings 164 to the element interior 102 of the filter element 16. In the interior of the valve housing 120, the fluid pressure of the clean fluid side of the filter element 16 is applied.

[0197] In case that the filter element 16, respectively, the filter medium 98, for example, due to separated particles, is partially or completely blocked, the pressure difference between the raw fluid side and the clean fluid side increases, i.e., between the interior of the valve seat element 126 and the interior of the valve housing 120. The pressure difference effects an opening force in axial direction on the valve plate 130. As soon as the opening force surpasses the spring force of the valve return element 124, the bypass valve arrangement 18 is opened.

[0198] Thus, the raw fluid can pass directly through the bypass valve arrangement 18 into the element interior 102 of the filter element 16 and from there to the fluid outlet 30. In this way, in case of blocked filter element 16, fluid can pass through the filter 12.

[0199] The diffuser device 20 according to the first embodiment is illustrated in detail in FIGS. 4 and 5. The diffuser device 20 comprises a diffuser connection section 200 and a fluid guiding section 202. The diffuser connection section 200 comprises a circular cylindrical diffuser connection socket 206 that is coaxial in relation to the diffuser main flow axis 204. The diffuser connection socket 206 surrounds a diffuser inlet channel 208.

[0200] In exemplary fashion, the diffuser device 20 is manufactured as one-piece component by use of thermoplastic material, for example, of a group of polyamide, polyester, polypropylene or another thermoplastic material, for example, according to an injection molding process.

[0201] The diffuser main flow axis 204 indicates the main inflow direction of the fluid out of the fluid outlet 30 of the filter element 16 into the diffuser connection section 200.

[0202] At the free end of the connection socket 206 that is facing axially the fluid outlet 30 of the filter 12, the rim is formed at the radially inner circumferential side as an insertion ramp 212. The insertion ramp 212 facilitates the insertion of the outlet socket 34 into the diffuser connection socket 206.

[0203] Axially behind the insertion ramp 212, the radially inner circumferential side of the connection socket 206 is designed as a circumferential connection seal surface 210. The connection seal surface 210 is coaxial circular cylindrical. With mounted diffuser device 20, the seal ring 42, which is located at the outlet socket 34 of the filter, is resting, acting sealingly in radial direction, on the connection seal surface 210.

[0204] Two fixation elements 214, each in an exemplary fashion of a one-piece configuration, are arranged in the form of locking elements radially outside of the diffuser connection socket 206. The fixation elements 214 are located on radially oppositely positioned sides. The fixation elements 214 each comprise a fastening arm extending parallel to the diffuser main flow axis 204. The fastening arms are connected with one end by means of a web to the radially outer circumferential wall of the diffuser connection socket 206 in a one-piece configuration. The fastening arms project in axial direction past the free rim of the diffuser connection socket 206. At the free ends of the fastening arms, a radially inwardly oriented locking nose is realized, respectively. With mounted diffuser device 20, the locking noses of the fixation elements 214 lock behind the locking collar 38 at the outlet socket 34 of the filter housing 14 and form in this way a quickly connectable locking connection, separable without being destroyed, between the diffuser device 20 and the filter housing 14.

[0205] Diffuser connection socket 206 passes at its side facing axially away from the free end into the fluid guiding section 202 in a one-piece configuration. The fluid guiding section 202 itself is also of a one-piece configuration. The fluid guiding section 202 comprises as a whole eight fluid guiding channels 216, for example. The fluid guiding channels 216 are arranged in an exemplary fashion in two channel groups. 224. Each channel group 224 comprises four of the fluid guiding channels 216.

[0206] The fluid guiding channels 216 have in an exemplary fashion identical shape and dimensions. At their radially inner side, the fluid guiding channels 216 through respective fluid connection openings 228 are connected to the diffuser inlet channel 208. In relation to the diffuser main flow axis 204, the fluid guiding channels 216 extend radially outwardly at a slant to the diffuser main axis 204. At the radially outer circumferential side, the fluid guiding channels 216 each comprise a channel outlet opening 230 that is rectangular in an exemplary fashion.

[0207] The fluid guiding channels 216 each have a rectangular cross-section in an exemplary fashion. The fluid guiding channels 216 widen in their width, tangentially to the diffuser main flow axis 204, viewed from their respective fluid connection opening 228 toward the channel outlet opening 230.

[0208] Each fluid guiding channel 216 is delimited by two central fluid guiding surfaces 218 that are oppositely positioned relative to a respective channel axis 222 and two lateral fluid guiding surfaces 220 that are also oppositely positioned relative to the channel axis 222. The fluid guiding surfaces 218 and 220 each are planar. The two central fluid guiding surfaces 218 extend parallel to each other. Also, the two lateral fluid guiding surfaces 220 extend parallel to each other. The central fluid guiding surfaces 218 and the lateral fluid guiding surface 220 of a fluid channel 216 extend perpendicularly to each other. The lateral fluid guiding surfaces 220 each have the shape of a parallelogram. The central fluid guiding surfaces 218 each have the shape of an isosceles trapezoid. The central fluid guiding surfaces 218 of a channel group 224 extend parallel to each other.

[0209] The central fluid guiding surfaces 218 each are realized at central channel walls 225. Neighboring central fluid guiding surfaces 218 of neighboring fluid channels 216 of a channel group 224 are realized on oppositely positioned sides of the same central channel wall 225. The lateral fluid guiding surfaces 220 on the same side of a channel group 224 are realized at a common lateral channel wall 227. The lateral channel walls 227 as a whole have the shape of a parallelogram. The central channel walls 225 and the lateral channel walls 227 are also planar, for example. An imaginary plane, which is defined by the rims of the channel outlet openings 230 of a channel group 224, extends parallel to the diffuser main flow axis 204. In an exemplary fashion, the planes of the rims of the channel outlet opening 230 of the two oppositely positioned channel groups 224 extend also parallel to each other.

[0210] The two channel groups 224 with the respective four fluid channels 216 are arranged on oppositely positioned sides in relation to the diffuser main flow axis 204. For example, the channel groups 224 are arranged and configured symmetrically in relation to an imaginary symmetry plane with the diffuser main flow axis 204. The channel groups 224 are located respectively on the same side of the diffuser connection socket 206 where also one of the fixation elements 214 is located. In this manner, the force introduction via the fixation elements 214 into the outlet socket 34 can be improved.

[0211] The fluid channels 216, respectively the channel axes 222, and the central fluid guiding surfaces 218 extend respectively at an acute angle 226 relative to the diffuser main flow axis 204.

[0212] The angle 226 amounts to approximately 120°, for example. The angle 226 can comprise also a different value, preferably between 90° and 180°. Due to the incline of the fluid guiding channels 216 and the central fluid guiding surfaces 218 relative to the diffuser main flow axis 204, the filtered fluid that flows into the diffuser inlet channel 208 is correspondingly deflected.

[0213] Upon operation of the filter 12, the fluid to be filtered flows through the fluid inlet 54 into the interior of the housing connection part 24. From there, the fluid to be filtered flows into an annular chamber of the housing pot 22 that surrounds the filter medium 98 radially outwardly. From the annular chamber, the fluid to be filtered flows through the filter medium 98 in radial direction from the exterior to the interior, is filtered by it, and reaches the element interior 102. The filtered fluid passes through the central tube 50 into the outlet socket 34.

[0214] In case the filter medium 98 is clogged, the fluid to be filtered passes directly through the bypass valve arrangement 18 into the element interior 102 and from there into the outlet socket 34.

[0215] The fluid flows out of the outlet socket 34 into the diffuser inlet channel 208 and flows along the diffuser main flow axis 204 in the diffuser inlet channel 208.

[0216] The fluid is distributed onto the eight fluid guiding channels 216 so that the flow cross section is enlarged as a whole. Due to the enlargement of the flow cross section, the flow is slowed and calmed. The thus already calmed fluid is then guided in the fluid guiding channels 216 along the fluid guiding surfaces 218 and 220 and, due to the widening of the fluid guiding channels 216, is further calmed. Also, the flow direction of the fluid is deflected with the fluid guiding channels 216.

[0217] The calmed fluid passes through the channel outlet openings 230 into the tank 10.

[0218] Due to the slowing of the fluid flow, it is achieved that the fluid remains longer in the tank 10 as it would be the case without the diffuser device 20. In this manner, gas that is entrained in the fluid, for example, air, can be separated better. Due to the directional deflection of the fluid flow upwardly in direction of the fluid surface in the tank 10, also gas bubbles in the filtered fluid are forced to move to the liquid surface. In this way, the gas bubbles are separated from the fluid.

[0219] In FIG. 9, a filter arrangement with two filters 12 is shown. Those elements that are similar to those of the filter 12 of FIGS. 1 through 8 are provided with the same reference characters. The filters 12 are connected fluidically in parallel. The respective fluid inlets 14 are connected to each other by a central fluid inlet socket 358 and are connectable by means of a common connection flange 56 to corresponding fluid supply line.

[0220] In FIGS. 10 and 11, a filter arrangement is illustrated with two filters 412 in perspective view and in section. In contrast to the filter 12 of FIGS. 1 through 8, in the second embodiment the bypass valve arrangements 18 of the filters 412 are arranged spatially at the bottom in the filter housings 14. Instead, the respective fluid outlets 430 are spatially arranged at the top. Diffuser devices, as in the first embodiment, are dispensed with in the embodiment of FIGS. 10 and 11.

[0221] In FIGS. 12 and 13, a bypass valve arrangement 18 according to a second embodiment is illustrated. Those elements that are similar to those of the filter 12 of FIGS. 1 through 8 are provided with the same reference characters. In contrast to the first embodiment of FIGS. 1 through 8, in the second embodiment the valve seat element 126 forms partially the circumferential wall of the valve housing 120. The valve seat 134 is located axially approximately at the center of the circumferential wall of the valve housing 120. The valve seat element thread 192 is embodied as an inner thread in the region of the free end of the circumferential wall. The valve housing thread 174 is realized as an outer thread on the part of the bottom section 146.

[0222] The guide cylinder 140 for the valve closure body 122 is hollow. The guide cylinder 140 is open at both ends and connects the interior of the valve closure body 122 to the environment below the bottom section 146.

[0223] Moreover, in the second embodiment of the bypass valve arrangement 18, instead of the operating element 198 in the form of a hexagon socket, a plurality of operating elements 498 in the form of openings are arranged, distributed circumferentially, at the end face of the valve seat element 26. The radially outer circumferential side of the bottom section 146 is designed as an external hexagon at which corresponding tools, for example, wrenches or the like, can engage for assembly of the bypass valve arrangement 18.

[0224] In FIGS. 14 to 16, a diffuser device 20 according to a second embodiment is illustrated. Those elements that are similar to those of the filter 12 of FIGS. 1 through 8 are provided with the same reference characters. In contrast to the first embodiment of FIGS. 1 through 8, in the second embodiment as a whole four channel groups 224, each with three fluid guiding channels 216, are distributed uniformly about the diffuser main flow axis 204.

[0225] The radially outer rims of the central fluid guiding surfaces 218 extend along an imaginary coaxial circular cylinder wall. The fluid guiding channels 216 widen outwardly. The central fluid guiding surfaces 218 widen in fluid flow direction.

[0226] Viewed in axial direction, the fluid guiding channels 216 each extend approximately spirally. Viewed in radial direction, the fluid guiding channels 216 each extend approximately helically.