Filter Element Having Projecting Bayonet-Type Protrusion

Abstract

A filter element is provided with a filter medium and a first end disk connected to the filter medium. A first bayonet protrusion is disposed on the first end disk and designed to engage behind a first bayonet receptacle of a filter housing of a filter. The first bayonet protrusion has a free end. The first bayonet protrusion projects at least over sections thereof in a radial direction relative to a filter element longitudinal axis of the filter element past the filter medium. The free end projects in the radial direction toward the filter element longitudinal axis. A filter with a filter housing provided with a first bayonet receptacle is provided and the filter element is arranged in the filter housing such that the first bayonet protrusion on the first end disk engages behind the first bayonet receptacle of the filter housing.

Claims

1. A filter element comprising: a filter medium; a first end disk connected to the filter medium; a first bayonet protrusion disposed on the first end disk and configured to engage behind a first bayonet receptacle of a filter housing of a filter; the first bayonet protrusion comprising a free end; the first bayonet protrusion projecting at least over sections thereof in a radial direction relative to a filter element longitudinal axis of the filter element past the filter medium; the free end projecting in the radial direction toward the filter element longitudinal axis.

2. The filter element according to claim 1, wherein the first bayonet protrusion relative to the filter element longitudinal axis projects at least with sections thereof in the radial direction past the first end disk.

3. The filter element according to claim 1, wherein the first bayonet protrusion comprises a stop edge extending parallel to the filter element longitudinal axis.

4. The filter element according to claim 1, further comprising a second bayonet protrusion disposed on the first end disk and configured to engage behind a second bayonet receptacle of the filter housing, wherein the second bayonet protrusion, relative to the filter element longitudinal axis, is embodied with axial symmetry relative to the first bayonet protrusion.

5. The filter element according to claim 1, further comprising a second end disk, wherein the filter medium is arranged between the first end disk and the second end disk, and wherein the second end disk comprises a stay extending at least over sections thereof parallel to the filter element longitudinal axis.

6. A filter comprising: a filter housing comprising a first bayonet receptacle; a filter element arranged in the filter housing and comprising: a filter medium and a first end disk connected to the filter medium; a first bayonet protrusion disposed on the first end disk and engaging behind the first bayonet receptacle of the filter housing; the first bayonet protrusion comprising a free end; the first bayonet protrusion projecting at least over sections thereof in a radial direction relative to a filter element longitudinal axis of the filter element past the filter medium; the free end projecting in the radial direction toward the filter element longitudinal axis.

7. The filter according to claim 6, further comprising a central column extending at least partially in the direction of the filter element longitudinal axis, wherein the first bayonet receptacle is disposed on the central column.

8. The filter according to claim 7, further comprising a heating element arranged on the central column.

9. The filter according to claim 7, further comprising a water level electrode arranged on the central column.

10. The filter according to claim 6, wherein the filter element further comprises a second end disk, wherein the filter medium is arranged between the first end disk and the second end disk, and wherein the second end disk comprises a stay extending at least over sections thereof parallel to the filter element longitudinal axis, wherein the stay is supported on a projection of the filter housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Further features and advantages of the invention result from the following detailed description of an embodiment of the invention, with the aid of the figures of the drawing illustrating details important to the invention, as well as from the claims.

[0046] The features illustrated in the drawing are illustrated such that the inventive particularities are clearly visible. The different features can be realized each individually or several combined in any combinations in variants of the invention.

[0047] FIG. 1 shows a perspective partially sectioned view of a filter in the form of a fuel filter with a filter element.

[0048] FIG. 2 is a sectioned side view of the fuel filter of FIG. 1.

[0049] FIG. 3 is a sectioned side view of the fuel filter according to FIG. 2 with partially unscrewed cover.

[0050] FIG. 4 is a perspective view of the filter element from above.

[0051] FIG. 5 is a perspective view of the filter in operating state.

[0052] FIG. 6 is a perspective view of the filter according to FIG. 5 when demounting the filter element.

[0053] FIG. 7 shows a perspective view of the filter element from below.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0054] FIG. 1 shows a filter 10 in the form of a fuel filter, here a diesel filter, for filtering media in the form of fuel, here in the form of diesel, comprising a filter housing 12 and a filter element 14 installed in the filter housing 12. The filter housing 12 comprises a filter housing body 16 and a cover 18. The cover 18 is screwed by a thread 20 onto the filter housing body 16. For exchange of the filter element 14, the cover 18 is unscrewed from the filter housing body 16.

[0055] The filter element 14 is designed to filter out dirt and separate water in multiple stages in order to fulfill high requirements in regard to the purity and waterlessness of the filtered fuel. The filter element 14 comprises for this purpose a filter medium 22. The filter medium 22 is folded several times to a star shape in order to provide a great surface area. Following the flow of the fuel, the filter element 14 comprises a first coalescing medium 24 adjoining the filter medium 22 that is in the form of a nonwoven.

[0056] Water droplets form on the first coalescing medium 24. Downstream of the first coalescing medium 24, a coarser second coalescing medium 26 for enlarging the water droplets is provided. The second coalescing medium 26 is contacting inwardly a support body 28. Between the support body 28 and a final separator screen 30, a sedimentation gap 32 is formed. The final separator screen 30 functions as a “baffle plate” for separating the water droplets which, following the force of gravity, flow via the sedimentation gap 32 into a water collecting chamber 34 of the filter housing 12.

[0057] In the filter housing 12, water level electrodes 36, 38 are provided that are spaced apart relative to each other in order to detect when the maximum filling level of the water in the water collecting chamber 34 is reached. The water level electrodes 36, 38 are arranged in a central column 40. The central column 40 comprises a fuel drain 42.

[0058] FIG. 2 shows the fuel filter 10 in a sectioned side view. FIG. 2 shows that the central column 40 is reversibly detachably connected to the filter element 14. The central column 40 is coupled in this context by sealing rings 44, 46 to the filter element 14. Moreover, the central column 40 is reversibly detachably connected to the filter housing body 16. The central column 40 is coupled by a sealing ring 48 to the filter housing body 16. The sealing rings 44, 46, 48 are formed as radial sealing rings, respectively.

[0059] The filter element 14 is installed suspended from the filter housing body 16. For connecting the filter element 14 with the filter housing body 16, a first bayonet protrusion 52 is provided on a first end disk 50 of the filter element 14. The first bayonet protrusion 52 is designed for engaging behind a first bayonet receptacle 54 of the filter housing body 16. The first bayonet protrusion 52 and the first bayonet receptacle 54 form a part of a bayonet connection 56.

[0060] In FIG. 2, the cover 18 is completely screwed onto the filter housing body 16 or partially screwed into the latter. In this state, the bayonet connection 56 is open, i.e., the filter element 14 is vibration decoupled from the filter housing body 16.

[0061] The filter element 14 comprises a second end disk 58. The second end disk 58 is arranged opposite the first end disk 50 in direction of the filter element longitudinal axis 60. The second end disk 58 comprises an internal sealing element groove 62 whose opening is facing away from the filter element longitudinal axis 60 in radial direction. An internal sealing element 64 is arranged in the internal sealing element groove 62. The internal sealing element 64 is in the form of a radial sealing element, more precisely, in the form of an O-ring. The internal sealing element 64 separates a clean side 66 from a raw side 68 of the fuel filter 10. The internal sealing element 64 prevents fuel from passing from the raw side 68 to the clean side 66 or into the water collecting chamber 34.

[0062] The fuel filter 10 comprises a drainage device 70 in the form of a plug. Through the drainage device 70, separated water (together with purified fuel) can be drained. After drainage of the water, the drainage device 70 can be closed in order to subsequently drain—separate from water and purified fuel—unpurified fuel by unscrewing the cover 18 and exchange the filter element 14.

[0063] The internal sealing element 64 contacts with frictional connection a wall section of the cover 18. The sealing action between the internal sealing element 64 and the wall section of the cover 18 that is resting against the internal sealing element 64 has in this context a greater friction coefficient than the bayonet connection 56. When unscrewing the cover 18, the filter element 14 is thus turned together with the cover 18. In doing so, the bayonet connection 56 closes. When the bayonet connection 56 is closed, the bayonet connection 56 blocks a further rotation of the filter element 14 relative to the filter housing body 16. Upon further rotation of the cover 18 (unscrewing the cover 18), a rotation of the cover 18 relative to the filter element 14 occurs instead. The cover 18 is thus unscrewed from the filter housing body 16 while the filter element 14 stays connected to the filter housing body 16.

[0064] FIG. 3 shows the fuel filter 10 with cover 18 partially unscrewed. The internal sealing element 64 is disengaged from the cover 18. In this way, unpurified fuel from the raw side 68 can drain in the direction of arrow 72 into the cover 18. The unpurified fuel can thus be collected separate from water and purified fuel in the cover 18 prior to filter element exchange. The escape of fuel into the environment is prevented in this context by an external sealing element 74. The seal between cover 18 and filter housing body 16 by means of the external sealing element 74 is still closed when the sealing action between filter element 14 and cover 18 by the internal sealing element 64 is already canceled. In this way, the exclusive fuel drainage into the cover 18 when unscrewing the cover 18 is reliably ensured.

[0065] The external sealing element 74 is designed in the form of a radial sealing element, here in the form of an O-ring. The external sealing element 74 is arranged in an external sealing element groove 76.

[0066] For heating the fuel, in particular for filtering the diesel fuel, a heating element 78 is provided in the fuel filter 10. The heating element 78 is arranged on the central column 40. The central column 40 is connected fixedly with the filter housing body 16. The first bayonet receptacle 54 and a second bayonet receptacle 84 are formed on the central column 40.

[0067] FIG. 4 shows the filter element 14 in an individual illustration. The filter element 14 comprises the first end disk 50 and the second end disk 58. The filter medium 22 is arranged between the end disks 50, 58. On the first end disk 50, the first bayonet protrusion 52 and a second bayonet protrusion 92 are formed. The bayonet protrusions 52, 92 project in relation to the filter element longitudinal axis 60 in radial direction completely past the filter medium 22 as well as partially past the first end disk 50. The bayonet protrusions 52, 92 are designed with axial symmetry relative to the filter element longitudinal axis 60. The example of the first bayonet protrusion 52 illustrates that the bayonet protrusions 52, 92 have a free end 94 which is projecting radially toward the filter element longitudinal axis 60. In this way, sharp, free outwardly projecting edges at the bayonet protrusions 52, 92 are avoided and a large mounting space above the first end disk 50 for arranging the heating element 78 is provided. The bayonet protrusions 52, 92 have moreover a stop edge 96.

[0068] FIG. 5 shows the filter 10 (without cover) in the operating state. In the operating state, the bayonet protrusions—of which in FIG. 5 the first bayonet protrusion 52 is visible—are disengaged from the bayonet receptacles—of which in FIG. 5 the first bayonet receptacle 54 is visible.

[0069] FIG. 6 shows in contrast thereto the filter 10 (without cover) during demounting. By rotation of the cover 18 (see FIGS. 2 and 3), the bayonet protrusions—of which in FIG. 6 the first bayonet protrusion 52 is visible—are in engagement with the bayonet receptacles—of which in FIG. 6 the first bayonet receptacle 54 is visible. When exchanging the filter element, the filter element 14 is thus suspended from the filter housing body 16 after unscrewing the cover 18.

[0070] FIG. 7 shows the filter element 14 in a view from below. The filter element 14 comprises at its second end disk 58 several stays 98, 100, 102, 104, 106, 108, 110, 112. The stays 98, 100, 102, 104, 106, 108, 110, 112 serve as a turning handle for the filter element 14. Moreover, the stays 98, 100, 102, 104, 106, 108, 110, 112 serve in the mounted state of the filter element 14 as a support relative to the cover 18, as can be seen in FIG. 2 which shows in an exemplary fashion the support of the stay 100 on a projection 114 of the cover 18. The stays 98, 100, 102, 104, 106, 108, 110, 112 are of axial symmetry relative to the filter element longitudinal axis 60.

[0071] In summary, the invention concerns a filter element comprising a filter medium. The filter element is connectable by means of at least one bayonet protrusion of the filter element to a filter housing of a filter. The bayonet protrusion projects in radial direction, i.e., perpendicularly to the central longitudinal axis of the filter element, past the filter medium. Moreover, the free end of the bayonet protrusion faces in the direction toward the central filter element longitudinal axis. The configuration according to the invention of the bayonet protrusion provides a large free mounting space in the area of the bayonet protrusion and avoids injuries because the free end of the bayonet protrusion projects in radial direction inwardly.