Abstract
A filter device having a filter housing (2) and a filter element (15) accommodated therein, the element material (44) of which for filtering a liquid extends between two end caps (40, 42), at least one end cap (40) of which is mounted on an element receptacle (14), wherein a bearing (46, 54), providing more than one degree of freedom, is used to articulate the filter element (15) on the element receptacle (14) via its one end cap (40), characterized in that the bearing has a convex bearing surface (46) that is guided in a concave bearing surface (54) and in that the respective bearing surface (46, 54) is part of a shell (55a, 55b), at least one (55b) of which has a passage (55c) for liquid media.
Claims
1. A filter device having a filter housing (2) and a filter element (15) accommodated therein, the element material (44) of which for filtering a liquid extends between two end caps (40, 42), at least one end cap (40) of which is mounted on an element receptacle (14), wherein a bearing (46, 54), providing more than one degree of freedom, is used to articulate the filter element (15) on the element receptacle (14) via its one end cap (40), characterized in that the bearing has a convex bearing surface (46) that is guided in a concave bearing surface (54) and in that the respective bearing surface (46, 54) is part of a shell (55a, 55b), at least one (55b) of which has a passage (55c) for liquid media.
2. The filter device according to claim 1, characterized in that the bearing has at least one convex bearing surface (46) guided in at least one concave bearing surface (54).
3. The filter device according to claim 1, characterized in that the respective convex bearing surface (46) is part of the element receptacle (14) and the respective concave bearing surface (54) is part of the one end cap (40).
4. The filter device according to claim 1, characterized in that the two bearing surfaces (46, 54), in contact with each other in the manner of a plug-in or clamp connection, are spherical.
5. The filter device according to claim 1, characterized in that the element receptacle (14) is secured in the filter housing (2) preferably by means of a screw connection (12, 26).
6. The filter device according to claim 1, characterized in that the longitudinal axis of the filter element (15) can in sections be swiveled out of the longitudinal axis of the element receptacle (14) in all directions by a predeterminable swivel angle by means of the spherical bearing (46, 54).
7. The filter device according to claim 1, characterized in that a blocking device (30, 61), delimiting the maximum possible deflection angle of the filter element (15), is provided, wherein said blocking device (30, 61) acts between the end cap (40) of the filter element (15) and the element mount (14) and is formed by these two.
8. The filter device according to claim 1, characterized in that a further blocking device (64, 66, 68, 70) is provided, which, when the element receptacle (14) of the filter element (15) is screwed to a housing mount (6), arranged inside the filter housing (2), prevents the swivel motion out of a basic position, in which the longitudinal axes of the one end cap (40) and the assigned element receptacle (14) are congruent with each other, and in that, when the element receptacle (14) is secured to the housing mount (6) and in the event of further rotational motion of the one end cap (40) relative to the element receptacle (14), preferably in the screw-on direction, the further blocking device (64, 66, 68, 70) permits the swivel motion from the basic position.
9. The filter device according to claim 1, characterized in that the further end cap (42) of the filter element (15) is secured to a further housing mount (74) inside the filter housing (2), and in that the further housing mount (74) is preferably part of a housing cover (78) that is secured to a filter head (80) as part of the filter housing (2), in particular by means of at least one screw connection (84).
10. The filter device according to claim 1, characterized in that the one housing mount (6) has at least one spring-loaded bypass valve (24), which, in its open position, while at least partially bypassing the filter element (15), releases the fluid path from the inside of the filter housing (2) to its outlet (4).
11. The filter element, in particular for a filter device according to claim 1, the element material (44) of which is arranged between two end caps (40, 42) while delimiting an inner cavity (55d), characterized in that at least one of the end caps (40) has a shell-like, preferably spherically shaped, bearing surface (46), which comprises a passage (55c) for liquid media, wherein said passage (55c) is connected to the cavity (55d) in a fluid-conveying manner.
Description
[0019] The invention is explained in detail below with reference to an exemplary embodiment shown in the drawing. In the Figures:
[0020] FIG. 1 shows a perspective oblique view, sectioned in a central and vertical sectional plane, of the exemplary embodiment of the filter device according to the invention;
[0021] FIG. 2 shows an enlarged perspective oblique view, sectioned in a central vertical plane, of the one end cap and its assigned element receptacle of the filter element of the exemplary embodiment;
[0022] FIG. 3 shows a perspective oblique view, further enlarged compared to FIG. 2, showing the area of two blocking devices of the exemplary embodiment, both shown in the blocking position; and
[0023] FIG. 4 shows a representation corresponding to FIG. 3, wherein one of the blocking devices is shown in the releasing position.
[0024] With reference to the drawings, the invention is explained by way of example of a so-called in-tank filter device, which has a filter housing 2 in the form of a tubular body open at its lower end 4. The invention is equally advantageously implemented in a filter device which provides a filter housing in the form of a filter bowl closed at the bottom. Near the lower end 4, a housing mount 6 is secured to the inside of the tubular body of the filter housing 2. The housing mount 6 is formed by a two-part annular body having a coaxial internal passage 8. At the top part 10, the passage 8 continues with an upwardly projecting threaded connector 12, to the male thread of which the female thread of a threaded ring 26 of an element receptacle 14 can be screwed for the support a filter element 15. The female thread can be used to detachably secure the element receptacle 14 in the filter housing 2. In the lower part 16 of the housing mount 6 valve chambers 18, arranged distributed around the outside of the central passage 8, for bypass valves are formed, which have fluid passages from an upper circular ring surface 20 of the upper part 10 to fluid passages 22 on the lower part 16. The fluid passages 22 are normally closed by spring-loaded closing elements 24.
[0025] FIG. 1 shows the filter element 15 in the installed functional position, in which the threaded ring 26, projecting coaxially downward from the element receptacle 14, is screwed to the threaded connector 12 of the housing mount 6, wherein for the tightened screw connection, the end 28 (see FIG. 2) of the threaded ring 26 contacts the circular ring surface 20 of the upper part 10. As can be seen most clearly from FIG. 2, the threaded ring 26 extends from the underside of a planar annular top surface 30, extending in a radial plane, of the element receptacle 14, wherein from the outer periphery of said top surface 30 a bell-like sleeve 32 extends toward the threaded ring 26. The sleeve 32 has wall openings 34 and delimits an annular space 36 between itself and the threaded ring 26. In the screwed functional position, shown in FIG. 1, the lower annular edge 38 of the sleeve 32, like the end 28 of the threaded ring 26, is in contact with the circular ring surface 20 of the upper part 10 of the housing mount 6.
[0026] In a conventional manner, the filter element 15 has an element material 44, extending between the end caps 40 and 42, in the form of a hollow cylinder. The one end cap 40, shown at the bottom in FIG. 1, of the end caps 40, 42 is supported on the element receptacle 14. To form the bearing, the element receptacle 14, see FIGS. 2 to 4, has a tubular body 48 projecting coaxially upwards from the cover surface 30, wherein the radially outer wall of said tubular body 48 forms a bearing surface 46 in the form of a convexly curved annular surface. The end cap 40 has, starting from the radially inner edge of a flat contact surface 50 for the front end of the element material 44, an upwardly and downwardly projecting tubular body 52, the radially inner wall of which forms the second bearing surface 54 in the form of a concavely curved annular surface.
[0027] The figures, see in particular FIG. 2, show the bearing state, in which the tubular body 52 of the end cap 40 is fitted onto the tubular body 48 of the element receptacle 14, wherein elastic flexibility, in particular of the tubular body 48 free-standing on the cover surface 30, can be used to latch the bearing to the adjoining bearing surfaces 46, 54. The contact of the convex bearing surface 46 with the concave bearing surface 54 forms a spherical bearing in the manner of a ball joint between the end cap 40 and the element receptacle 14. The respective bearing surface 46, 54 is constituent part of membrane-like shell 55a, 55b, at least one 55b of which has a passage 55c for fluid, which is connected to a cavity 55d in the filter element in a fluid-conveying manner. The enclosure for the element material 44, contacting on the contacting surface 50 of the end cap 40, is formed on the radial inside by the tubular body 52 and on the radial outside by a sleeve surface 56, which widens upward in the radial direction to form a shell 58 surrounding the end part of the element material 44 at a radial distance.
[0028] The spherical bearing formed permits a deflection of the longitudinal axes of the element receptacle 14 relative to the filter element 15 from the aligned basic position as shown in FIGS. 1 and 2. In this aligned position, the lower edge 61 of the tubular body 52 of the end cap 40 is spaced apart from the top surface 30 of the element receptacle 14. In contrast, FIGS. 3 and 4 show a deflected state, or more precisely, the maximum possible deflection at which the lower edge 60 of the annular body 52 contacts the cover surface 30, forming a stop, of the element receptacle 14. This forms a blocking device delimiting the maximum deflection.
[0029] FIGS. 2 to 4 show closer details of a further blocking device formed by formations on the upper end edge 60 of the tubular body 48 of the element receptacle 14 and the upper end edge 62 of the tubular body 52 of the end cap 40. As shown, this blocking device has a locking block 64, projecting radially inwards from the inside of the end edge 62 of the tubular body 52 and having the form of a short rectangular rib. At the end edge 60 of the other, inner tubular body 48 a recess 66 is formed, which extends in steps 68 and 70 (see in particular FIGS. 3 and 4) across one circumferential section of the tubular body 48 each. In the first step 68, the recess 66 forms an axial deepening of the end edge 62 corresponding to the axial thickness of the locking block 64 and is limited in the circumferential direction by a projection 72, protruding slightly from the step surface, to a circumferential length only slightly greater than the length of the locking block 64 measured in the circumferential direction, see FIG. 3. The second step 70 adjoins the first step 68 at the projection 72, wherein said second step results in the end edge 62 being further recessed in the axial direction and has a greater circumferential length than the first step 68.
[0030] In this arrangement, the function of this further blocking device is as follows: FIGS. 2 and 3 show the basic position in which the axis of filter element 15 together with the end cap 40 is aligned with the longitudinal axis of the element receptacle 14. The locking body 64 of the end cap 40 is located in the first step 68 of the recess 66 of the tubular body 48 of the element receptacle 14. Because the axial extension of the first step 68 corresponds to the thickness of the locking block 64 measured in the axial direction, the spherical bearing is blocked against deflection. At the same time, the projection 72 impedes the sliding motion of the locking block 64 in the circumferential direction, so that in this basic position a rotational interlock is formed between the filter element 15 and the element receptacle 14. In the basic position, therefore, during the assembly process for installing the filter element 15 in the filter housing 2, the filter element 15 together with the element receptacle 14, forming a rigid unit therewith, can be conveniently and securely placed against the threaded ring 26 of the housing mount 6 and screwed tight by the rotary catch formed. When the screw connection is formed, the rotational interlock, formed by the projection 72, can be overcome by further rotation such that the locking block 64 overruns the projection 72 and enters the free space formed by the second step 70 of the recess 66. Due to the increased axial depth of the step 70, the locking block 64 is no longer axially supported, permitting the spherical bearing to be released and within the limits formed by the first blocking device to be deflected to compensate for misalignment.
[0031] The other, upper end cap 42, in the exemplary embodiment shown, see FIG. 1, engages with an element receptacle formed by a connector 74 that engages with the central opening 76 of the end cap 42. Instead of this form-fit engagement, a spherical bearing of the type shown on the lower end cap 40 can also be provided between the upper end cap 42 and the element receptacle concerned. The connector 74, provided in the example shown, is constituent part of a housing cover 78 that is removably secured to a filter head 80 using screw connections 85, wherein said filter head 80 has an unfiltered input 82 and, as per usual for in-tank filter devices, is attached to an opening in a tank wall not shown. In the functional position shown in FIG. 1, the end 28 of the threaded ring 26 and the end edge 38 of the element receptacle 14 are in close contact with the circular ring surface 20 of the housing mount 6. For the unfiltered matter gaining access to the bypass valves in the lower part 16 of the housing mount 6, the annular space 36 located inside the sleeve 32 forms an inflow space into which unfiltered matter enters via the wall openings 34. Openings 84 are provided in the circular ring surface 20, forming the bottom of this annular space 36, wherein said openings 84 are normally closed by the closing bodies 24 of the respective bypass valve. Injected screen grids may be provided at the wall openings 34 of the sleeve 32 to provide filtration of the flow of unfiltered matter when a bypass valve is opened by pressure. In an embodiment not shown, it is also possible to relocate the spherical bearing presented from the lower to the upper element end, or to provide such a bearing at both element ends.
