FILTER DEVICE WITH DRAINAGE MEANS IN THE COVER

Abstract

A suspended filter device may include a ring filter element arranged in a receiving space. A cover may be securable to a housing from beneath for closing the receiving space. A drainage element may be arranged at the bottom of the cover in an installed state, and a pin may be disposed on the filter element and be configured to close the drainage element. A dome may engage into an interior of the filter element from below when the cover is installed. A guide contour may be disposed on a free end of the dome and interact with a guide element disposed on the filter element. A spring may be supported on the cover and on the dome, and may be configured to prestress the ring filter element in an upward direction into the housing via the dome.

Claims

1. A suspended filter device, comprising: a ring filter element arranged in a receiving space, a cover and a housing, wherein the cover in an installed state for closing the receiving space is securable to the housing from beneath, wherein the housing includes an inlet and an outlet, a drainage element arranged in the installed state below the ring filter element on the cover through which the receiving space can be drained, an eccentrically and axially projecting pin arranged on the ring filter element, wherein the pin closes the drainage element when the ring filter element is inserted in the receiving space and the receiving space is closed with the cover, tubular dome that engages into an interior of the ring filter element from below when the cover is installed, a guide contour disposed on a free end of the dome, wherein the guide contour interacts with a guide element that is arranged on the ring filter element and facilitates an alignment of the pin relative to the drainage element, a spring arranged between the cover and the ring filter element, wherein the spring is supported on the cover and on the dome and the ring filter element is preloaded upwards into the housing via the dome, wherein the guide contour on the dome includes an axial groove, wherein the axial groove guides the guide element during assembly and is arranged relative to the pin so that the pin is insertable into the drainage element on a cover side when the guide element engages the axial groove, wherein the guide contour is configured as a bevelled cannula, and wherein the axial groove is arranged on a low point of the bevelled cannula, and wherein at least one of: the filter element is connected in a torque-proof manner with the cover and is axially displaceable when opening or closing the cover, and the filter element is removable together with the cover from the housing and the filter element is removable from the cover via a pulling force.

2. The filter device according to claim 1, wherein the spring is configured so that in a relaxed state the spring lifts the dome and the ring filter element an extent sufficient for the pin to disengage from the drainage element and the ring filter element is still held on the dome.

3. The filter device according to claim 1, wherein the spring includes a coil spring and is held in a spring guide contour arranged both in the cover and the dome.

4. The filter device according to claim 1, wherein the guide element includes a guide pin which is directed radially inwards or radially outwards.

5. The filter device according to claim 1, wherein the guide element is arranged on a support structure-like internal frame of the ring filter element, and wherein the internal frame is enclosed at an end face by a respective end disc.

6. The filter device according to claim 1, further comprising a sealing lip arranged at least on the end disc that is proximate to the guide element wherein the sealing lip sealingly bears against an outer surface of the tubular dome when the ring filter element is installed.

7. The filter device according to claim 6, wherein the end disc and the sealing lip are formed in one piece.

8. The filter device according to claim 1, further comprising another tubular dome disposed on the housing and arranged to engage in the interior of the ring filter element from the top.

9. The filter device according to claim 1, wherein the guide element is a guide pin.

10. The filter device according to claim 9, wherein the guide pin is arranged on an internal frame of the ring filter element.

11. The filter device according to claim 10, further comprising an end disc coupled to an end face of the ring filter element, wherein the end disc includes a sealing lip that sealingly bears against an outer surface of the dome when the ring filter element is installed.

12. The filter device according to claim 2, wherein the spring is a coil spring.

13. The filter device according to claim 12, wherein the coil spring is mounted in a spring guide contour, and wherein the spring guide contour is disposed in at least one of the cover and the dome.

14. A suspended filter device for an internal combustion engine, comprising: a housing including an inlet and an outlet; a ring filter element arranged in a receiving space; a cover for closing the receiving space and securable to the housing; a drainage element disposed on the cover and arranged beneath the ring filter element for draining the receiving space; an axially projecting pin arranged eccentrically on the ring filter element, wherein the pin closes the drainage element when the ring filter element is inserted into the receiving space and the receiving space is closed by the cover; a guide element arranged on the ring filter element; a tubular dome arranged to engage into an interior of the ring filter element when the cover is installed, wherein the dome has a free end that includes a guide contour configured to interact with the guide element and facilitate an alignment of the pin relative to the drainage element; a spring arranged between the cover and the ring filter element when the cover is installed, wherein the spring is supported on the cover and the dome so that the ring filter element is preloaded upwards into the housing via the dome; wherein the guide contour includes an axial groove configured to guide the guide element during assembly, wherein the axial groove is arranged so that the pin is insertable into the drainage element on a cover side when the guide element engages the axial groove; and wherein the guide contour is configured as a beveled cannula, and wherein the axial groove is arranged on a low point of the beveled cannula.

15. The filter device according to claim 14, wherein the filter element is connected with the cover in a torque-proof manner.

16. The filter device according to claim 15, wherein the filter element is axially displaceable only when opening or closing the cover.

17. The filter device according to claim 15, wherein the filter element is removable together with the cover from the housing, and wherein the filter element is removable from the cover via a pulling force.

18. The filter device according to claim 14, wherein the filter element is removable together with the cover from the housing, and wherein the filter element is removable from the cover via a pulling force.

19. The filter device according to claim 14, wherein the spring has a length dimensioned in a relaxed state to lift the dome together with the ring filter element an extent sufficient for the pin to disengage from the drainage element and the ring filter element is still held on the dome.

20. The filter device according to claim 14, wherein the spring is mounted in a spring guide contour arranged in at least one of the cover and the dome.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] There it shows, in each case schematically,

[0018] FIG. 1 a filer device according to the invention in a sectional representation,

[0019] FIG. 2 a detail representation from FIG. 1 in the region of a spring preloaded dome with preloaded spring,

[0020] FIG. 3 a representation as in FIG. 2, however with at least partly relaxed spring,

[0021] FIG. 4 an internal view of a cover of the filter device,

[0022] FIG. 5 a representation as in FIG. 4, however with partly sectioned dome,

[0023] FIG. 6 an exploded representation of the cover of the filter device with spring and dome.

DETAILED DESCRIPTION

[0024] According to FIGS. 1 to 3, a filter device 1 according to the invention, for example an oil or fuel filter, comprises a receiving space 2, in which a ring filter element 3 is arranged suspended. The filter device 1 additionally comprises a housing 4, which can be closed with a cover 5 from beneath. The cover 5 in this case can be screwed to the housing 4 from below. In order to be able to remove the liquid that is present in the housing 4 or in the cover 5 during a change of the ring filter element 3 and thereby drain the receiving space 2, a drainage means 6 is provided below on the cover 5, which, with the filter device 1 ready for operation, is closed by an eccentrically arranged and axially projecting pin 7 on the ring filter element 3. According to the invention, a first tubular dome 8 is additionally provided, which with mounted filter device 1 engages into an interior of the ring filter element 3 from beneath. On an upper free end of the first dome 8 a guide contour 9 is arranged here, which interacts with a guide element 10 that is arranged on the ring filter element 3 and brings about alignment of the pin 7 relative to the drainage means 6. Likewise provided is a spring 11, which supports itself on the one hand on the cover 5 and on the other hand on the dome 8 and via the same preloads the ring filter element 3 upwards into the housing 4. When disconnecting the cover 5, the spring 11 causes the ring filter element 3 to be preloaded upwards into the housing 4 at all times and because of this when screwing the cover 5 downwards is released with its pin 7 from the drainage means 6, as a result of which the fluid, for example oil or fuel that is present in the receiving space 2, can be drained. Even before the cover 5 can thus be completely unscrewed from the housing 4, the receiving space 2 is drained. However, following the unscrewing of the cover 5, i.e. following its disconnection from the housing 4, the ring filter element 3 remains on the first dome 8 and thus on the cover 5, as a result of which easy removal by an assembler or worker is made possible. A new ring filter element 3 is subsequently placed onto the dome 8 in the cover 5, wherein when closing the cover by turning or screwing on the cover 5 the spring 11 is preloaded and because of this pushes the ring filter element 3 into the housing 4 or on a second dome 12 arranged up there. Through the increased friction between the second dome 12 and for example an upper end disc 13 of the ring filter element 3, the ring filter element 3 by way of the guide contour 9 on the first dome 8 or cover 5 turns so that the pin 7 can be introduced into the drainage means 6 in an accurately fitting manner. Compared with suspended filter devices known from the prior art, the ring filter element 3 in the case of the filter device 1 according to the invention, does not remain in the housing 4 following complete unscrewing of the cover 5, but can be simply removed with the cover 5.

[0025] The length of the spring 11 in this case is dimensioned so that in the relaxed state it lifts the first dome 8 and in addition to this the ring filter element 3 so far that on the one hand the pin 7 no longer engages in the drainage means 6 closing the same and on the other hand the ring filter element 3 is still held on the first dome 8. Such a situation is shown for example in FIG. 3. With completely screwed-on cover 5, as is shown for example according to FIGS. 1 and 2, the pin 7 engages in the drainage means 6 thereby closing the same. In the present case, the spring 11 is formed as a coil spring and held in a spring guide contour 14, 14 both in the cover 5 and also in the first dome 8. The spring guide cover 14 in the cover 5 is clearly evident from FIGS. 1 to 5, whereas the spring contour 14 on the dome 8 is evident from FIGS. 1 to 3 and 6. The spring guide contour 14 on the cover side engages about the spring 11 and additionally comprises a third dome 15, which engages in the interior of the spring 11. Both the cover 5 and also the first dome 8 can be formed as plastic injection moulding in a cost-effective manner, wherein the respective spring guide contours 14, 14 are simultaneously injection-moulded on.

[0026] Looking at the guide contour 9 on the dome side it is evident that the same has an axial groove 16, to which the guide element 10 is guided during the assembly of the filter device 1. This axial groove 16 is arranged relative to the pin 7 so that the latter can be introduced into the drainage means 6 on the cover side, provided the guide element 10 enters the axial groove 16. The guide contour 9 can be formed in the manner of a bevelled cannula, wherein the axial groove 16 is arranged on the lowest point. The guide element 10 can for example be formed as a guide pin which is directed radially to the inside or radially to the outside. In the present case, the guide element 10 is arranged on a support structure-like internal frame 17 of the ring filter element 3, wherein this internal frame 17 is enclosed on the face end by the upper end disc 13 and a lower end disc 18.

[0027] On the lower end disc 18, which is adjacent to the guide element 10, a sealing lip 19 is arranged, which with installed ring filter element 3 sealingly bears against an outer surface of the tubular first dome 8 and thereby fluidically separates an interior from an exterior. The end disc 18 and the sealing lip 19 in this case can be preferentially formed in one piece, in particular as a one-piece plastic injection moulding.

[0028] With the filter device 1 according to the invention it is possible for the first time, with suspended filter housings 4, to make possible a low-contamination and thereby clean replacement of the ring filter element 3. With previous filter devices with suspended filter housings, a drainage screw had to be opened before opening the cover in order to remove for example the old oil from the receiving space. Although embodiments were known in the case of which an axially projecting pin that is eccentrically moulded onto an end disc closes a drainage means in the cover, both embodiments however had in common that after the removal of the cover the ring filter element remained suspended in the filter bowl, i.e. in the present case in the housing 4, and the worker therefore had to hold the smudgy ring filter element with his hands in order to change it. With the filter device 1 according to the invention this is no longer necessary since when screwing on the cover 5 the spring 11 provided according to the invention lifts the ring filter element 3 and extracts the pin 7 from the drainage means 6, as a result of which the fluid, for example oil, that is present in the receiving space 2 can be drained. Following drainage of the receiving space 2, the cover 5 can be completely unscrewed and removed, wherein in this case the ring filter element 3 remains on the dome 8 on the cover 5 and can therefore be easily changed.

[0029] When unscrewing the cover 5, the ring filter element 3 is disconnected from the housing 4 since the ring filter element 3 during the rotary movement is still fixed by the pin 7 in the drainage means 6 and the retaining forces of the upper O-ring located between ring filter element 3 and dome 12 are relaxed. In order to further amplify the disconnecting effect, the middle upper mounting could be additionally embodied conical, as a result of which the contact between ring filter element 3 and housing 4 when turning on is lost very early on.

[0030] The assembly of a new ring filter element 3 is similarly easy since the same need to be merely placed onto the dome 8 on the cover 5 and subsequently the cover 5 screwed to the housing. By means of the guide contour 9 and the guide element 10, alignment of the pin 7 relative to the drainage means then takes place, so that the pin 7 with completely screwed-on cover 5 is sealingly pushed into the drainage means 6.