Filter Device

Abstract

In a filter device having a filter housing, in which a replaceable filter element (4) is housed and which has a cover member (2), and in which an element member (30) is partitioned at an end by at least one end cap (32), at least one end cap (32) of the filter element (4) is attached to a flow path (58), and a part (84) for supporting a lateral force against the filter element (4) is provided between the one end cap (32) and the flow path (58), and the filter element (4) is supported against the flow path (58) which is at least partially engaged at an end inside the filter element (4).

Description

[Technical Field]

[0001] The present invention relates to a filter device comprising a filter housing in which a replaceable filter element is housed, the filter housing having a cover member, the element member being bounded at its ends by at least one end cap. [Background technology]

[0002] Various embodiments of this type of filter device have been disclosed in the past, including those with replaceable filter elements conforming to different specifications. In this type of filter device, the filter element is used, in particular, for fluid maintenance in hydraulic systems. As shown in Patent Document 1, which discloses a filter device of the type mentioned at the beginning, such a filter device can be advantageously designed as a so-called in-tank filter device. In this solution, the filter element begins in a cover member that forms a closure for a wall opening in a container or tank storing the fluid and extends to the interior of the tank. In this case, the length of the filter element is dimensioned so that the lower end cap is below the lowest liquid level expected during operation. During filtration, unfiltered liquid enters the inner filter cavity of the filter element through the opening in the lower end cap. After flowing through the element member from the inside to the outside, the fluid reaches the interior of the tank as filtrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] German Patent Application Publication No. 102015003604(A1) Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to proceed from this prior art and to provide an apparatus of the type mentioned at the outset which is characterized by particularly favourable operating characteristics. [Means for solving the problem]

[0005] According to the invention, the above object is achieved by a filter device having the features of claim 1 in its entirety.

[0006] According to the characterizing portion of claim 1, an essential feature of the present invention is that at least one end cap of a filter element is attached to a flow passage, and a component for supporting a lateral force against the filter element is provided between the one end cap and the flow passage, supporting the filter element against the flow passage at least partially engaged at its end inside the filter element. When the filter device is installed in a container or tank and the flow passage is fixed to the tank bottom, the effective lateral force support between the end cap and the flow passage forms a safety device against displacement or twisting due to forces acting on the outside of the filter element. For example, when used in mobile work equipment, similar loads may occur due to flow forces caused by fluid sloshing due to tank movement and dynamic loads caused by acting acceleration forces acting on the filter element.

[0007] In a preferred embodiment of the filter device according to the invention, the end caps are provided with a device for supporting lateral forces, which is preferably connected to the end cap in the form of an insert. In this way, the device for supporting lateral forces can be connected to the end cap as one end of an element, which is particularly advantageous from a manufacturing point of view. Solutions are also conceivable in which the device for supporting lateral forces is an integral part of the end cap.

[0008] In a further preferred embodiment of the device according to the invention, it is provided that the device for supporting lateral forces is formed from a sleeve, one end of which has an inwardly bent edge and the other end of which forms a peripheral wall as part of the guide for the flow path, and on the outer periphery of the peripheral wall is formed a ledge-like annular flange which engages in a stepped recess in one of the end caps.

[0009] In order to improve the guidance, it may also be advantageous to provide that the peripheral wall tapers slightly in the direction of its inwardly curved edge in order to improve the contact pressure position on the outer periphery of the flow channel.

[0010] In a particularly advantageous embodiment, the inwardly curved edge of the sleeve is provided to form a kind of stop as a part supporting lateral forces, which preferably forms a possible end stop for the filter element with respect to the stationary flow passage protruding into the tank housing. In this way, a safety device is formed that prevents the filter element from accidentally falling into the tank, which may occur, especially if the filter element is removed from the lid at its opposite end for removal purposes. Furthermore, the stop can serve as an end stop when the filter element is placed around the outer periphery of the flow passage.

[0011] In this case, the free inner diameter defined by the inwardly curved edge is preferably smaller than the free inner diameter of the flow passage in the region of the adjacent free end.

[0012] More advantageously, one free end of the element member facing one end cap can be arranged to abut flat against the portion of the end cap adjacent to the recess and the ledge-shaped annular flange of the stop, so that the free end of the element member on the end face side is supported by abutting on a flat surface on both sides.

[0013] In an advantageous embodiment, a protruding receiving ridge is formed on the end cap as a further part of the guide piece, the conically converging guide surface of the receiving ridge being directed towards the receiving opening for engagement of the flow channel, the tapered guide surface thus forming a funnel-shaped insert aid when the end cap is placed on the flow channel.

[0014] To obtain a seal between the end cap equipped with the device for bearing lateral forces and the flow passages engaging at their ends in the filter element, the associated end cap is provided with an annular sealing lip which surrounds the flow passage with a predetermined abutment force.

[0015] In this case, the sealing lip can preferably be provided as a separate part of the device for supporting lateral forces, which on the one hand seals around the flow passage with a given contact force and on the other hand is stationary relative to the flow passage.

[0016] To further improve the seal, the sealing lip may have a radial flaring portion that projects toward the interior of the filter element and contracts as the flow passage engages within the end cap. Particularly advantageously, the sealing lip may be an integral component of one of the end caps and be resiliently flexible. In this case, the sealing lip may be an integral component of the end cap or may be made of a plastic with resilient properties that can be molded to the end cap.

[0017] To improve the seal, it is advantageous to define the free edge of the annular sealing lip to have a diameter smaller than the outer diameter of the flow passage in the initial state before the flow passage engages in the end cap. To facilitate the insertion of the flow passage into the assigned end cap, the conicity of the guide-receiving ridge preferably corresponds to the conicity of the inwardly curved sealing lip.

[0018] The present invention will be described in detail below based on the embodiments shown in the drawings. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 shows a perspective view of an embodiment of a filter device according to the present invention, cut vertically along a central vertical plane. [Figure 2] FIG. 2 shows an enlarged perspective view of only the lower end region of the embodiment, cut along a central vertical plane and truncated. [Figure 3] FIG. 3 shows the lower end region of the embodiment fitted in the flow path corresponding to FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] In Fig. 1, which depicts the entire embodiment configured as an in-tank filter device, the cover element is designated 2. Together with the outlet pipe 6, which forms the outer jacket of the filter element 4, the cover element 2 forms the filter housing of the filter device. The circular cover element 2 has a slightly convexly curved upper surface 8 and a trough-shaped inner chamber 10, the bottom 12 of which has a concave curvature corresponding to the curvature of the upper surface 8. The inner chamber 10 is laterally bounded by a cylindrical side wall 14 having an external thread 16. To install the filter device in a tank (not shown), the cover element 2 can be screwed with the external thread 16 of the side wall 14 to a fixing flange 20 in a wall opening in the upper tank wall of the tank.

[0021] To form a detachable connection between the lid member 2 and the filter element 4, which is a separate housing part, the filter element 4 has fastening means on the upper end cap 18 that form-fit with retaining means in the interior chamber 10 of the lid member. The fastening means of the end cap 18 comprises three fastening bars 22 on its upper side near its outer periphery, offset from one another at angular intervals of 120°, only one of which is visible in FIG. 1 . For each fastening bar 22, a retaining section 24 is molded into the bottom 12 of the interior chamber 10 of the lid member 2, within which is a blocking channel 26 extending along a circular arc section. By rotating the filter element 4 and the lid member relative to each other and moving them into the locked position shown in FIG. 1 , an angled blocking strip 28 separate from the assigned fastening bar 24 can enter the blocking channel 26. This form-fitting lock creates a kind of bayonet lock.

[0022] The filter element 4 includes a hollow, cylindrical element member 30 extending conventionally between an upper end cap 18 and a lower end cap 32. Received within the end caps 18 and 32 are a support tube 34 and the end of the outlet tube 6, which has through-holes 36 (see FIGS. 2 and 3) for fluid passage therethrough. The support tube 34 is formed by a lattice-like, fluid-permeable support structure having a plurality of spaced-apart radially extending annular segments 38 connected by elongated bars 40 (FIG. 3).

[0023] Between the annular segments 38, circumferentially arranged wings 42 extend in the form of flat strips as spacers for the inside of the outlet pipe 6, so that an intermediate space 44 is formed between the outside of the element element 30 and the outlet pipe 6. During filtering operation, when the fluid flows through the element element 30 from the inner filter cavity 46 to the outside, the intermediate space 44 forms the filtrate side of the filter arrangement, from where the filtrate flows through the through-holes 36 of the outlet pipe 6 into the interior of the tank.

[0024] The upper end cap 18 has a central opening 48 which allows passage from the filter cavity 46 to the interior chamber 10 of the lid member 2, but which is normally closed by a bypass valve closure 50 located within the interior chamber 10 of the lid member.

[0025] The bypass valve has a guide sleeve 52 that protrudes coaxially from the bottom 12 of the cover member 2, within which the shaft of the closure body 50 is displaceably guided. The bypass valve has a compression spring 54 that surrounds the guide sleeve 52 and biases the closure body 50 into the closed position, and is clamped between the closure body 50 and the bottom 12.

[0026] 2 and 3 show a detailed embodiment in the region of the lower end cap 32. The lower end cap 32 has a central opening 56 for the nonfiltrate to flow into the inner filter cavity 46. To supply the nonfiltrate, a channel is provided in the bottom region of the tank (not shown) in the form of a fixed pipe socket 58 with a rounded edge 60 at its free end. The lower end cap 32 has a flat abutment surface 62 on its upper side, which serves as a frame for the opposing ends of the element member 30 and the support tube 34. The lower end cap 32 is bounded on its radially outer side by a peripheral edge 64 that protrudes axially upward. The peripheral edge 64 has latch notches 65 on its inner side, into which latch projections 66 of the support tube 34 can engage, thereby securing the support tube 34 axially to the end cap 32. Adjacent to the peripheral edge 64, the abutment surface 62 has a flat surface that transitions radially inward to the opening 56. The recess 70, which is stepped at its radially inner end, forms the transition to the opening 56.

[0027] The end cap 52 forms an annular sealing lip 72 molded at its end axially offset from the recess 70 of the central opening 56, which has the shape of a thin tongue in cross section, opening obliquely downward from the wall of the opening 56 and then extending obliquely upward toward the filter element 4. The sealing lip 72 has elastic flexibility depending on the elastic properties of the plastic material forming the end cap 32. The end cap 52 forms a deepened recessed channel 74 in a circumferential region radially outwardly adjacent the peripheral edge 64, in which a slot-like annular chamber 80 is formed between the outer peripheral edge 76 and the inner annular body 78, and into which the outflow pipe 6 is inserted and received.

[0028] The end cap 32 extends downwardly from the recess 70 on its underside with a channel-shaped section 82, the end of which is molded with the sealing lip 72. The channel section 82, together with a guide sleeve 84, forms a guide for the tube socket 58. When the filter element 4 is installed, the tube socket 58 extends through the opening 56 in the end cap 32 into the inner filter cavity 46. The sleeve 84 has a radially outwardly projecting annular flange 88 above its lower end 86, which is received in the opening 56 in the end cap 32. The annular flange 88 is then received within the recess 70 so that the upper side of the annular flange 88 is flush with the surrounding abutment surface 62. The other upper end of the sleeve 84 has an inwardly curved edge 90 that forms a stop for the upper edge 60 of the tube socket 58.

[0029] To provide an insertion aid when installing the filter element 4, the end cap 32 includes a ring of molded, circumferentially arranged, wing-like, axially downwardly projecting guide ridges 92 as guide means adjacent the lower end of the opening 56. The guide ridges 92 have their radially inner edges forming guide surfaces 94 that extend conically upwardly and inwardly with a conicity corresponding to that of the undeformed sealing lip 72. In this manner, the guide surfaces 94 collectively define a type of insert funnel that facilitates installation of the filter element 4 into the tube socket 58.

[0030] Upon installation and insertion into the guide formed by the flow passage section 82 of the opening 56 and the sleeve 84, the radial overhang of the edge 96 of the sealing lip 72 is reduced from the position shown in Figure 2, and in the installed position shown in Figure 3, the sealing lip 72 exerts a resilient sealing force to seal against the tube socket 58. At the same time, the guide provides lateral force support within the sleeve 84 against the end cap 32, and thus the filter element 4 in the stationary, fixed tube socket 58. While lateral force support is shown for the lower end cap 32, it could also be provided for the upper end cap 18 or both end caps 18, 32, if desired. The present invention has the following aspects (configurations). [Aspect 1] A filter device comprising a filter housing, A filter device containing a replaceable filter element (4) and having a cover member (2), the element member (30) being bounded at its ends by at least one end cap (32), a filter device, characterized in that at least one end cap (32) of the filter element (4) is attached to a flow passage (58), and a part (84) for supporting a lateral force for the filter element (4) is provided between the end cap (32) and the flow passage (58), and the part (84) for supporting a lateral force supports the filter element (4) at least partially at the end with respect to the flow passage (58) that engages with the interior of the filter element (4). [Aspect 2] 2. The filter device according to claim 1, wherein the end cap (32) has the part (84) for supporting lateral forces preferably formed as an insert member connected to the end cap (32). [Aspect 3] 3. The filter device according to claim 1 or 2, characterized in that the part (84) for supporting lateral forces is formed from a sleeve, the sleeve having an inwardly bent edge (90) at one end and a peripheral wall at the other end serving as a guide for the flow passage (58), and a ledge-shaped annular flange (88) formed on the outer periphery of the peripheral wall and engaging in a stepped recess (70) in the one end cap (32). [Aspect 4] 4. The filter device according to any one of the preceding aspects, characterized in that the inwardly curved edges (90) form a kind of stop, which forms a possible end stop for the filter element (4) with respect to a stationary arranged flow channel (58). [Aspect 5] 5. The filter device according to any one of the first to fourth aspects, wherein the free inner diameter defined by the inwardly curved edge (90) is smaller than the free inner diameter of the flow channel (58) in the region of the free end. [Aspect 6] A filter device according to any one of aspects 1 to 5, wherein one free end of the element member (30) facing the one end cap (32) is in planar contact with a portion (62) of the one end cap (32), and the portion (62) is adjacent to a stepped recess (70) and a ledge-shaped annular flange (88) of the stop portion. [Aspect 7] A filter device according to any one of aspects 1 to 6, characterized in that a receiving ridge (92) is formed on the end cap (32) as a further part of the guide portion, with a conically converging guide surface (94) facing towards the receiving opening (56) for engagement with the flow channel (58). [Aspect 8] The filter device according to any one of aspects 1 to 7, wherein the end cap (32) has an annular sealing lip that surrounds the flow path (58) with a predetermined contact force. [Aspect 9] The filter device according to any one of the first to eighth aspects, wherein the sealing lip (72) is a separate part of the part (84) for supporting lateral forces, and surrounds the flow passage (58) as a seal with a predetermined abutment force and is stationary relative to the flow passage (58). [Aspect 10] A filter device according to any one of Aspects 1 to 9, wherein the sealing lip (72) has a radial protrusion that protrudes toward the interior (46) of the filter element (4), and the radial protrusion is reduced when the flow passage (58) engages with the end cap (4). [Aspect 11] A filter device according to any one of aspects 1 to 10, wherein the sealing lip (72) is an integral component of the one end cap (32) and has elastic flexibility. [Aspect 12] A filter device according to any one of aspects 1 to 11, wherein the receiving opening (56) for engaging with the flow passage (58) is defined by a sealing lip (72). [Aspect 13] 13. The filter device according to any one of aspects 1 to 12, wherein in an initial state before the flow passage (58) engages with the end cap (4), the free edge (96) of the annular sealing lip (72) has a diameter smaller than the outer diameter of the flow passage (58). [Aspect 14] 14. The filter device according to any one of the preceding aspects, wherein the conicity of the guide-receiving ridge (92) corresponds to the conicity of the protruding sealing lip (72).

Claims

1. A filter device comprising a filter housing, A filter device in which a replaceable filter element (4) is housed in the filter housing, the filter housing having a cover member (2), and the element member (30) is bounded at its ends by at least one end cap (32), the at least one end cap (32) of the filter element (4) is attached to a flow passage (58), and a part (84) for supporting a lateral force for the filter element (4) is provided between the at least one end cap (32) and the flow passage (58), and the part (84) for supporting a lateral force supports the filter element (4) at least partially at the end with respect to the flow passage (58) that engages with the interior of the filter element (4); the part (84) for supporting the lateral forces is formed from a sleeve having an inwardly curved edge (90) at one end and a peripheral wall at the other end as a guide for the flow passage (58); A filter device characterized in that a ledge-shaped annular flange (88) is formed on the outer periphery of the peripheral wall and engages within a stepped recess (70) in the at least one end cap (32).

2. 2. The filter device of claim 1, wherein said at least one end cap (32) comprises said part (84) for supporting said lateral force.

3. 3. A filter device according to claim 1 or 2, characterized in that the inwardly curved edge (90) forms a kind of stop, which forms a possible end stop for the filter element (4) with respect to the stationary arrangement of the flow passage (58).

4. 4. A filter device according to claim 1, wherein the free inner diameter defined by the inwardly curved edge (90) is smaller than the free inner diameter of the flow passage (58) in the region of its free end.

5. 4. The filter device according to claim 3, wherein one free end of the element member (30) facing the at least one end cap (32) is in planar contact with a portion (62) of the at least one end cap (32), the portion (62) being adjacent to the stepped recess (70) and the ledge-shaped annular flange (88) of the stop portion.

6. 6. A filter device according to claim 1, characterized in that a receiving ridge (92) is formed protruding from the at least one end cap (32) as a further part of the guide portion, and a conically converging guide surface (94) on the radially inner edge of the receiving ridge (92) faces towards the receiving opening (56) for engagement with the flow passage (58).

7. 7. The filter device of claim 6, wherein the at least one end cap (32) has an annular sealing lip (72) surrounding the flow passage (58) with a predetermined abutment force.

8. 8. The filter device according to claim 7, wherein the annular sealing lip (72) is another part of the part (84) for supporting the lateral force, and surrounds the flow passage (58) as a seal with a predetermined contact force and is stationary relative to the flow passage (58).

9. 8. The filter device of claim 7, wherein the annular sealing lip (72) has a radial flaring portion that projects toward the interior (46) of the filter element (4), the radial flaring portion being reduced when the flow passage (58) engages the at least one end cap (32).

10. 8. The filter device of claim 7, wherein the annular sealing lip (72) is an integral component of the at least one end cap (32) and is resiliently flexible.

11. 8. The filter device of claim 7, wherein the receiving opening (56) for engagement with the flow passage (58) is defined by the annular sealing lip (72).

12. 8. The filter device of claim 7, wherein in an initial state before the flow passage (58) engages the at least one end cap (32), the free edge (96) of the annular sealing lip (72) has a diameter smaller than an outer diameter of the flow passage (58).

13. 8. A filter device according to claim 7, characterized in that the conicity of the receiving ridge (92) corresponds to the conicity of the protruding annular sealing lip (72).

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