Filter device and filter element

Abstract

The present invention relates to a filter device comprising a filter housing 10 comprising at least an upper housing portion 12 and a lower housing portion 14, which at least partially removably receives a filter element 16, wherein the filter device comprises a control device 22 for controlling fluid flow in the upper housing portion 12, the control device 22 is controlled such that it disconnects a fluid connection between a fluid inlet 24 and a fluid outlet 26 in a shut-off position and releases the fluid connection in an open position, and the control device 22 is controlled by an actuator 44 on the filter element such that the control device 22 moves to the shut-off position when the lower housing portion 14 is separated from the upper housing portion 12 and the open position is established when the lower housing portion 14 is attached to the upper housing portion 12, wherein the control device 22 comprises at least one coupling The present invention relates to a filter device comprising a rotary slide valve housing 46 having elements 48, 50, wherein at least one connecting element 48, 50 cooperates with corresponding connecting elements 54, 56, 58, 60 on the filter element 16 as an actuator 44 to form at least one connecting portion 52, 53, and when the lower housing portion 14 is attached or removed, at least one of the corresponding connecting elements 54, 56, 58, 60 drives into contact with one associated connecting element 48, 50 of the rotary slide valve housing 46 in each case, and when the rotary slide valve housing 46 moves from the closed position to the open position or from the open position to the closed position, and thereafter when the rotary slide valve housing 46 is in either the open position or the closed position, the respective connecting portions 52, 53 are immediately released.

Description

Technical Field

[0001] The present invention relates to a filter device having a filter housing comprising at least an upper housing part and a lower housing part, which at least partially and interchangeably receives a filter element. The filter housing comprises a control device for controlling the fluid flow in the upper housing part. The control device separates the fluid connection between the fluid inlet and the fluid outlet in the blocking position and releases the fluid connection in the release position. The control device is controlled such that, by means of an operating device on the filter element, when the lower housing part is separated from the upper housing part, the control device moves to the blocking position and when the lower housing part is attached to the upper housing part, the release position is established.

[0002] The present invention further relates, in particular, to a filter element intended for use in the above filter device.

Background Art

[0003] Patent Document 1 (German Patent Application Publication No. 102021002511) discloses a filter device having a filter housing. The filter housing comprises at least two connection points such as an inlet for unfiltered medium and an outlet for filtered medium and receives an exchangeable filter element. A valve device is provided as a control device, which in the open position enables a fluid flow between one of these two connection points and the filter element and in the closed position blocks this fluid flow. Further, the valve device can be moved in both directions between the open position and the closed position by means of an operating device on the filter element. The valve device comprises a spring-loaded inlet valve arranged in the fluid flow between the inlet and the outer surface of the filter element and a spring-loaded outlet valve arranged in the fluid flow between the inner surface of the filter element and the outlet.

[0004] Patent Document 2 (German Patent Application Publication No. 102021002024) discloses a similar filter device and related filter element, wherein an inlet valve is positioned in the fluid flow between the inlet and the outer surface of the filter element, and comprises an inlet valve closing member as a control device, the inlet valve closing member being formed by a cylinder wall portion having an opening, the wall portion being guided to move within a slit in the filter housing such that, in the release position of the control device, its opening overlaps with the inlet.

[0005] When attaching the filter element to the filter device, the filter element is first inserted into the lower housing and then pushed into the upper housing of the filter device. The lower housing is then screwed into the upper housing, thereby rotating the inserted filter element and moving the inlet valve to the open position. When the filter element is fully screwed in and thus attached to the upper housing, the corresponding connecting elements on the lower end cap of the filter element and on the bottom of the lower housing can slide against each other via their respective inclined surfaces, thus realizing a kind of ratchet joint, and the lower housing can be fully screwed into the upper housing to obtain the operating position without further rotation of the filter element in this process. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] German Patent Application Publication No. 102021002511 Specification [Patent Document 2] German Patent Application Publication No. 102021002024 [Patent Document 3] German Patent Application Publication No. 10201401437 [Overview of the initiative] [Problems that the invention aims to solve]

[0007] Based on this prior art, the present invention aims to further improve known solutions, particularly in a way that enables the control of fluid flow with respect to a hydraulic device in a functionally reliable manner. [Means for solving the problem]

[0008] The above problems are solved by a filter device having the features of claim 1 and a filter element having the features of claim 1.

[0009] According to a characteristic feature of claim 1 of the present invention, the control device comprises a rotary slide valve housing having at least one coupling element, the at least one coupling element cooperating with a corresponding coupling element on the filter element as an actuator to form at least one coupling portion, and when the lower housing portion is attached or removed, at least one of the corresponding coupling elements in each case makes driving contact with one associated coupling element of the rotary slide valve housing, and when the rotary slide valve housing moves from the shut-off position to the open position or from the open position to the shut-off position, and thereafter when the rotary slide valve housing is in either the open position or the shut-off position, the respective coupling portions are immediately released, and all the essential operating elements for operating the control device are realized between the rotary slide valve housing and the adjacent end of the filter element, thereby providing functional reliability. Furthermore, this configuration can be implemented in particular space-saving manner. In addition, since there is a direct application of force between the actuator of the filter element and the adjacent rotary slide valve housing as a control device, operation can be performed without interference. Furthermore, spring valves, which are generally prone to failure, no longer need to be used in the control system. Fluid flow from a hydraulic device connected to a filter device and / or filter element can be obtained particularly safely.

[0010] In a particularly preferred embodiment of the filter device according to the present invention, each coupling is provided to be configured in the form of a ratchet coupling and to have two adjacent opposing pairs of spring tongues as corresponding coupling elements on the end cap of the filter element, projecting in a manner that elastically yields into the movement path of at least one control cam as one coupling element of the rotary slide valve housing. In this way, each control cam of the rotary slide valve housing forms its respective coupling element, and the two adjacent opposing pairs of spring tongues form the corresponding coupling element on the filter element. Thus, unlike the prior art, the ratchet coupling can be moved from the bottom side of the filter element to its top side and no longer interact with the lower housing portion, but rather interacts with the rotary slide valve housing within the upper housing portion, and the lower housing portion as a whole can form a filter container that is closed to the outside and screwed as a whole onto the filter head as the upper housing portion in the operating position. In this way, the filter container is not divided into one part integrally formed with the filter head and another part for the rotational movement of the filter element via a ratchet joint on the bottom side, thus simplifying the overall configuration of the filter device and allowing for cost-effective production. The necessary sealing between the filter container and the filter head is also simplified. This is also true for the removal and reinstallation of the filter container from the filter head.

[0011] In a further preferred embodiment of the filter device according to the present invention, a rotary slide valve housing is provided having two fluid passage points and two shut-off walls, which can be moved to cover the fluid inlet and outlet in an open or shut-off position.

[0012] The central positioning of the rotary slide valve housing within the filter head allows for the blocking of both the fluid inlet and outlet when the element is changed, thereby increasing functional reliability. In the desired embodiment, the absence of the filter element in the device results in increased pressure loss, which is usually due to oversight and can be detected.

[0013] In a further preferred embodiment of the filter device according to the present invention, the rotary slide valve housing is provided to have an additional control cam that is guided by a sliding guide in the upper housing portion and restricts the movement of the rotary slide valve housing between the shut-off position and the open position. Thanks to the sliding guide, the position of the rotary slide valve housing is fixed at its end position, thus eliminating the possibility of failure.

[0014] In a more particularly preferred embodiment of the filter device according to the present invention, a drive unit is provided between the filter element and the lower housing portion, which drives the filter element received in the lower housing portion in the same direction during relative movement between the fixed upper housing portion and the lower housing portion which is movable toward the upper housing portion. By connecting the filter container as the lower housing portion to the filter element via the corresponding drive unit, both friction lock and shape lock connections are achieved, thereby enabling reliable rotational drive for the filter element both when screwing the filter container onto the filter head and when screwing the filter container off the filter head, thereby ensuring that the actuator always operates the control device.

[0015] In a more preferred embodiment of the filter device according to the present invention, the rotary slide valve housing has an annular seal on the fluid outlet side within the upper housing portion, which, in the open position, seals the fluid transition area between the fluid outlet and the inner fluid passage within the rotary slide valve housing. To a person of the ordinary art, it is surprising that only one annular seal is required on the outlet side of the filter device, and that no further sealing device is required, especially on the inlet side. Therefore, one seal on the outlet side, where the fluid pressure is lower than on the inlet side of the filter device, is sufficient.

[0016] In a more preferred embodiment of the filter device according to the present invention, the inner fluid passage is provided to penetrate perpendicularly within the rotary slide valve housing and, at its free end facing away from the fluid outlet, has a connecting inclined portion on its interior for fluid connection of the filter element. Thanks to the perpendicular fluid guide, flow loss and cavitation are avoided, and thanks to the predetermined geometric shape of the aforementioned connecting inclined portion, a certain degree of counterfeit prevention is achieved, thereby ensuring that only the original high-quality filter element can be used as a replacement element in the filter device.

[0017] In a further preferred embodiment, the rotary slide valve housing is provided to have an additional internal fluid passage, which in the open position forms a fluid connection between the fluid inlet and the fluid chamber formed in the operating position by the filter element and the lower housing portion. In this way, an inclined plane can be formed in the fluid supply side, i.e., the fouling side, within the rotary slide valve housing in the filter head, which helps to avoid flow loss and cavitation.

[0018] In a more particularly preferred embodiment of the filter device according to the present invention, the rotary slide valve housing has at least one safety valve, which, in its shut-off position, opens and releases the corresponding passage when fluid flows through the rotary slide valve housing from the fluid inlet to the fluid outlet, bypassing the fluid chamber in the lower housing portion, and preferably a contamination indicator is connected to the corresponding passage. This ensures that if an undesirable flow occurs through the filter device when no filter element is inserted, a pre-pressure valve forming a safety valve is activated via a safety passage in the rotary slide valve housing, which opens when a set pre-pressure is reached, ensuring that a fluid safety connection is formed between the inlet and outlet without dangerous pressure rise. Preferably, if a contamination indicator, which may be configured as a differential pressure indicator, is connected to each passage, this contamination indicator can detect a fault. This ensures that the absence of a filter element in the operating position of the filter device can be reliably detected and avoided. The technical structure of such a contamination indicator is shown as an example in Patent Document 3 (German Patent Application Publication No. 10201401437) of the patent holder, and will not be discussed in further detail here.

[0019] Preferably, at least one bypass valve is housed within the rotary slide valve housing, and the bypass valve is further provided to release the fluid passage between the fluid inlet and fluid outlet during operation when the degree of contamination of the filter element exceeds a predetermined level in the open position, thereby bypassing the filter element. In this way, the function of the hydraulic system connected to the filter device can be ensured, and the system will be supplied with fluid at a predetermined pressure even if the filter element is clogged or blocked.

[0020] The object of the invention relating to improved control of fluid flow in a hydraulic device in a functionally reliable manner is also achieved by a filter element having the features of claim 11. According to the present invention, a filter element having an end cap on at least one free end face, comprising the element material, comprises individual connecting elements projecting outward as part of at least one connecting element on this end cap, so that an actuator is formed directly on the upper end of the filter element, and this actuator enables functionally reliable control of the fluid flow between the fluid inlet and outlet via further connecting elements on the control device of the filter device. In particular, the interaction between the actuator on the filter element and the control device on the filter housing of the filter device makes it impossible to reliably operate the filter device if the filter element is missing. In this way, operator error can be eliminated and reliable control of fluid flow in a hydraulic system fluid-connected to the filter element is guaranteed.

[0021] The end cap connecting element is preferably provided to be formed from at least one pair, preferably two pairs, of mutually adjacent and opposing spring tongues, each of which protrudes inward by a predetermined distance along the travel path. In this way, a key component of a kind of ratchet joint is provided on the filter element, thereby ensuring that the control device, generally in the form of a rotary slide valve housing, continues to operate periodically even when the filter element has not yet been completely removed or inserted into its operating position.

[0022] The travel path is preferably formed by shell-shaped guide surfaces as part of each connecting portion, these guide surfaces protruding beyond the associated end caps and each formed at the end by spring tongues. This combination of the travel path and the elastically flexible spring tongues ensures, on the one hand, reliable guidance of the connecting elements between the rotary slide valve housing and the filter element, which can be connected to each other, and on the other hand, allows the actuator to be deactivated as soon as the rotary slide valve housing is in the respective shut-off or open position within the filter housing.

[0023] In a further particularly preferred embodiment of the filter element according to the invention, the shell-shaped guide surface is surrounded outwardly by a retaining ring, which at least partially projects beyond the guide surface when viewed in the axial direction and is firmly connected, preferably integrally connected, to the associated end cap via webs. Preferably, the retaining ring projects beyond the edge of the end cap and has at least one projecting drive part in the direction of the end cap. In this way, the retaining ring and its drive part provide opportunities for frictional and form-locking fixation, and furthermore, the connecting element on the filter element is protected from mechanical damage. Also, this combination of the retaining ring and the connecting element results in a rigid independent structure for the filter element via the associated end cap.

[0024] In a particularly advantageous way, a socket joint is rotatably incorporated into the central opening of the end cap, and this socket joint is provided with a connection point that can be tilted in a predetermined direction for forming a fluid passage inside the filter element. The retaining ring provides options for a rigid connection for receiving the filter element, but the central fluid passage starting from the inside of the filter element can be achieved in a sealed manner via a movable, particularly tiltable connection point. In this process, on the one hand, it is surprising to those skilled in the art that the filter element as a whole can be firmly fixed and positioned via the retaining ring, and variability can be obtained via the socket joint with respect to the fluid passage, which also has the advantage that it can directly compensate for the difference in tolerances between the element holder and the fluid passage.

[0025] Particularly space-saving, the end of the element material surrounds the socket joint within the end cap holder so that the socket joint is supported outwardly by the element material, and the socket joint with its connection point can be moved without any force to the operating position for carrying fluid, making it possible to adapt the socket joint without hindrance.

[0026] In the following, a filter device according to the present invention will be described in more detail using an embodiment shown in the drawings. The following drawings are shown in principle, and the scale is not indicated in principle. [Brief explanation of the drawing]

[0027] [Figure 1] Figure 1 shows the overall filter device in a longitudinal cross-section, with the fluid inlet located on the left side and the fluid outlet on the right side. [Figure 2] Figure 2 shows a cross-section of the upper part of the filter device according to Figure 1, rotated 180° around the longitudinal axis of the filter device. The fluid inlet is located on the right side and the fluid outlet is located on the left side, and these are fluidly connected to each other in the open position shown in the figure. [Figure 3] Figure 3 is a representation corresponding to Figure 2, where the fluid connection between the fluid inlet and fluid outlet is isolated at the shut-off position. [Figure 4] Figure 4 shows the display corresponding to Figure 3 with the filter element removed and the safety valve open. [Figure 5] Figure 5 shows a partial view in which the connecting element of the rotary slide valve housing in the upper housing section contacts the corresponding connecting element on the end cap of the filter element, establishing a connecting connection. [Figure 6] Figure 6 shows the coupling engagement according to Figure 5 in a plan view, which includes two opposing coupling elements of the rotary slide valve housing and the corresponding pair of coupling elements on the end caps of the filter elements. [Figure 7] Figure 7 shows the cap configuration of the end cap shown in Figure 6, related to the filter element shown in Figures 1 to 3. [Figure 8] Figure 8 shows a longitudinal section passing through the end cap shown in Figure 7. [Figure 9] Figure 9 shows a portion of the rotary slide valve housing in the form of an exploded assembly view, with an adjacent portion of the lower housing having a filter element inserted together with the associated upper end cap. [Figure 10] Figure 10 shows an inclined view of the rotary slide valve housing according to Figure 9. [Figure 11] Figure 11 shows the individual components of the rotary slide valve housing shown in Figures 9 and 10 in a longitudinal cross-section. [Figure 12] Figure 12 shows the individual components of the rotary slide valve housing shown in Figures 9 and 10 in a bottom view. [Modes for carrying out the invention]

[0028] The filter device shown in Figure 1 has a filter housing 10 comprising an upper housing portion 12 and a lower housing portion 14, which are also referred to in technical terms as a filter head or filter container. The lower housing portion 14 is intended to receive a filter element 16 in a replaceable manner. The upper housing portion 12 is generally positioned at rest or in a fixed position as part of the overall hydraulic device, and the lower housing portion 14 can be firmly connected to the upper housing portion 12 in a releasable manner via a threaded portion 18. In particular, the lower housing portion 14, which forms a threaded portion 18 having a corresponding male thread, can be screwed into the female thread of the upper housing portion 12 in a releasable manner. Referring to Figure 1, a peripheral annular groove 20 is located above the male thread of the lower housing portion 14, and this groove is intended to receive an annular seal (not shown) at this point to seal the inside of the filter device from the environment.

[0029] The control device 22 is housed within the upper housing 12 to control the fluid flow. The control device 22 shuts off the fluid connection between the fluid inlet 24 and the fluid outlet 26 when in the shut-off position shown in Figure 3, and reopens this connection when in the open position shown in Figure 1. Both the fluid inlet 24 and the fluid outlet 26 are connected to the hydraulic (overall) device via standard piping (not shown). In this way, a fluid, for example, in the form of a hydraulic medium, can be cleaned of contaminating particles by the filter device shown in Figure 1. For this purpose, the unfiltered medium flows through the fluid inlet 24 into a hollow cylindrical fluid chamber 28, whose outer circumference is separated by the cylindrical inner wall of the lower housing 14 and by the outer jacket of a filter element 16, which is usually pleated.

[0030] Next, the unfiltered fluid flow flows from the fluid chamber 28 from the outside to the inside, through the element material 30 to be cleaned, and into the inside 32 of the filter element 16. While the fluid flow passes through the element material 30, the element material 30 is supported along the outer jacket of a hollow cylindrical support tube 34, the fluid passage 36 of the support tube 34 is only partially shown in Figure 1. The element material 30 removes any contaminating particles from the fluid flow, and as a result, the inside 32 of the filter element 16 forms the so-called filtered side of the filter device during operation. The cleaned fluid then passes through the fluid outlet 26 via a right-angled inner fluid passage 38 in the control device 22 for further use. Thus, together with the filter element 16, a further inner fluid passage 39 is formed by the flow path from the inlet 24 into the fluid chamber 28.

[0031] The element material 30 of the filter element 16 is received between the upper end cap 40 and the lower end cap 42, as shown in Figure 1. The end caps 40 and 42 function in the usual way as end enclosures for the free end faces of the element material 30. The specific structure of the upper end cap 40 will be described in more detail below, but the lower end cap 42 is supported in the usual way by the container or the bottom of the lower housing portion 14 or by the filter container, respectively.

[0032] The upper end cap 40 has an actuator 44, which allows the control device 22 to be operated such that when the lower housing portion 14 is separated from the upper housing portion 12, the control device 22 moves to the shut-off position, and when the lower housing portion 14 is attached to the upper housing portion 12, the release position shown in Figure 1 is established.

[0033] Figure 2 illustrates the upper housing portion 12 of the filter device, rotated 180° with respect to its longitudinal axis. The fluid inlet 24 is located on the right side in Figure 2, and the fluid outlet 26 is located to its left. The components shown in Figure 2 correspond to the solution according to Figure 1. As further shown in Figure 2, the control device 22 has a rotary slide valve housing 46 with two coupling elements 48, 50, which are diametrically opposed to each other with respect to the aforementioned longitudinal axis, and these coupling elements 48, 50 interact with the corresponding coupling elements 54, 56, 58, 60 on the filter element 16 as an actuator 44 to form two coupling portions 52, 53, and when the lower housing portion 14 is attached or removed, at least one of the corresponding coupling elements 54, 56, 58, 60 drives and engages with the respective associated coupling elements 48, 50 of the rotary slide valve housing 46 in each case, which moves from the shut-off position according to Figure 3 to the open position shown in Figures 1 and 2, or from the open position to the shut-off position, and as soon as the rotary slide valve housing 46 is in one of the shut-off and open positions, the respective coupling portions 52, 53 are subsequently released.

[0034] The solutions for each connection on the upper cap 40 can be seen in particular in Figure 7. Two semishells 62, 64 are provided projecting axially upward from the fluid permeable center of the upper cap 40, and these two semishells 62, 64 are preferably integral parts of the upper cap 40, which can be produced, for example, by plastic injection molding or 3D printing. The two semishells 62, 64 each have connecting elements 54, 60 or 56, 58 corresponding to their mutually opposing free ends. Thus, the adjacent corresponding connecting elements 54 and 56 or 58 and 60 each form part of the connecting portion 52 or 53. Each corresponding connecting element 54, 56, 58, 60 is formed from an elastically flexible spring tongue portion having an inwardly projecting locking lug 66 at its free end. Each spring tongue with a locking lug 66 is formed by a bottom recess 68 within each half-shell 62, 64, as a bottom recess opposite to the upper end cap 40 70, and this bottom recess extends horizontally as essentially a continuous surface in the operating position of the filter device. In this process, the spring tongues with the protruding locking lugs 66 protrude inward in the view shown in Figure 7 by a predetermined distance along a circular movement path 72, which is also demarcated by the inner guide surfaces 74 of the half-shells 62, 64.

[0035] When the lower housing portion 14 is screwed into the upper housing portion 12 counterclockwise from below as seen in Figures 5 and 6, and when the control device 22 or the rotary slide valve housing 46 is in a position to shut off the fluid connection between the inlet 24 and outlet 26 as shown in Figure 3, the locking lugs 66 of the corresponding diametrically opposed coupling elements 54, 58 of the two half-shells 62, 64 together carry the adjacent opposing coupling elements 48 and 50 of the control device 22, and as soon as they engage with each other from below as part of the screwing process, rotate the rotary slide valve housing 46 to the released position shown in Figures 1 and 2. If the rotary slide valve housing 46 is rotated to its corresponding released position, but the lower housing portion 14 with the filter element 16 is potentially not yet fully screwed in, the respective coupling portions 52, 53 function as ratchet joints, and the coupling elements 48, 50 located at their end positions are passed by the corresponding coupling elements 54, 60; 56, 58 without triggering further action. Therefore, when the lower housing portion 14 is screwed in further, the control device 22 or the rotary slide valve housing 46 will remain in the open position shown in Figures 1 and 2, respectively.

[0036] To replace the used filter element 16 with a new one, the lower housing portion 14 is unscrewed from the upper housing portion 12 in a clockwise direction, opposite to the aforementioned direction of rotation, and the locking lugs 66 of the corresponding connecting elements 56, 60 are brought into contact with the control cams or connecting elements 48, 50 of the rotary slide valve housing 46, which are diametrically opposite to each other with respect to the longitudinal axis of the device, thereby moving the rotary slide valve housing 46 from the open position shown in Figures 1 and 2 to the closed position for the fluid passage shown in Figure 3. Figures 5 and 6 show possible rotational states in the process as the rotary slide valve housing 46 attempts to move from its closed position to the initial position for carrying fluid or to the open position.

[0037] In particular, as can be seen from Figures 2 and 3, the rotary slide valve housing 46 is configured as a shut-off valve or plug valve as part of a switching valve, and has two fluid passage points 76, 78 (Figure 2) as well as two shut-off walls 80, 82 (Figure 3), which can be moved to cover the fluid inlet 24 and fluid outlet 26 in the open and shut-off positions, respectively. In this case, the two opposing arrows in Figure 3 inside the inlet 24 and outlet 26 indicate that in both possible fluid flow directions, the filter element 16 is separated from the corresponding fluid passage in the shut-off position in any case.

[0038] As can be seen from Figures 2 and 9-11, the rotary slide valve housing 46 has an additional cylindrical control cam 84 on the upper side as seen in the above figures, which is an integral part of the rotary slide valve housing 46 and is supported circumferentially by a kind of center or spring centering means 86. The corresponding additional control cam 84 is guided within an associated sliding guide 88 (Figure 2) in the upper housing portion 12 so as to restrict the possible movement of the rotary slide valve housing 46 between the shut-off position as shown in Figure 3 and the open position as shown in Figure 2 in both rotational directions. In this way, when relative movement occurs between the lower housing portion 14 and the upper housing portion 12 during the screwing or unscrewing process, it is prevented that the rotary slide valve housing 46 will be continuously driven unintentionally through the respective connecting portions 52, 53 to reach an undesirable intermediate position.

[0039] As can be seen further from Figures 2, 3, 10, and 12, the rotary slide valve housing 46 has an annular seal on the side of the fluid outlet 26 within the upper housing portion 12, which is not shown in detail, but rather only the associated receptacle 90 for the annular seal. Since the annular seal needs to cover several fluid openings, as will be described in detail, the associated annular receptacle 90 is provided with an intermediate portion 92 that extends linearly between adjacent curves 94, thereby forming a kind of flattened oval-shaped sealing body.

[0040] As shown in particular in Figure 4, which shows the filter device in its shut-off position with the filter element 16 not inserted into the lower housing portion 14 of the container shape, a possible flow path is opened between the fluid inlet 24 and the fluid outlet 26, and the possible flow path is indicated by the flow arrow. In the corresponding fluid passage, two diametrically opposed shut-off walls 80 and 82 each have further fluid openings 96 and 98, and through these further fluid openings 96 and 98, the possible fluid flow from the fluid inlet 24 passes through the fluid opening 96 facing the first shut-off wall 80 to the inside of the rotary slide valve housing 46, and from there passes through the further fluid opening 98 of the shut-off wall 82 to the side where the fluid outlet 26 is located. The rotary slide valve housing 46, which is configured in the form of a hollow chamber structure, has corresponding free flow paths between the inner support chamber walls of the rotary slide valve housing 46.

[0041] Furthermore, according to the cross-sectional view through the rotary slide valve housing 46 shown in Figure 11, two safety valves 100 are located within the possible flow path shown in Figure 4. Each safety valve 100 is configured as a so-called double valve; that is, each safety valve 100 also functions as a bypass valve 102. For this purpose, each valve 100, 102 is provided with an associated pair of closures 104 and 106, respectively, which are assigned to each other in pairs and supported on a connecting spring 108 configured as a compression spring. Thus, both the safety valve function and the bypass function can be performed with a single valve structure. The preload pressure for each valve function can be predetermined via the connecting spring 108, and when the pressure at the fluid inlet 24 exceeds a predetermined threshold, the two associated safety valves 100 open, one of which is only partially shown in Figure 4. Therefore, if flow is improperly routed through the aforementioned safety holes in the form of further fluid openings 96, 98 within the rotary slide valve housing 46 to a filter device without filter elements 16, each pre-pressure valve or safety valve 100 will be opened with the bypass valve 102 closed, and thus no unacceptably high fluid pressure will accumulate on the inlet side 24 of the filter device.

[0042] A contamination indicator 110 is screwed into the upper housing 12 from above and is configured as a differential pressure sensor for measuring and recording the differential pressure between two fluid channels 112, one of which leads to the inside of the upper housing 12 and guides the rotary slide valve housing 46 rotatably, as shown in Figure 4, while the other fluid channel 112 leads to the fluid outlet 26. Thus, if the set pre-pressure is exceeded, this excess can be detected by the differential pressure or contamination indicator 110, and the filter device can be used to rule out erroneous operation by the operator, i.e., operation of the filter device without the filter element 16 can be ruled out. Particularly as can be seen from Figure 10, the fluid passage points 78 and further fluid openings 98 within the barrier wall 82 are, optionally, edged by oval annular seals within the associated receptacle 90 and thus sealed from the environment.

[0043] When the filter device is in its filtration operation position as shown in Figure 2, and so-called blockage of the filter element 16 occurs due to contaminating particulate matter, the bypass valve 102 opens, bypassing the fluid chamber 28 containing the filter element 16 and opening a direct path from the fluid inlet 24 to the fluid outlet 26, so that the function of the entire hydraulic system to which the filter device is connected is not impaired, or even interrupted. Figure 12 shows the respective holders for the valves 100, 102 and the closing section 106 for the respective spring-loaded bypass valves 102, as viewed from below the rotary slide valve housing 46.

[0044] As can be seen from Figures 11 and 12, a wedge-shaped flow divider 116 is provided in the area of ​​the lower connector 114 that is visible at the upper end region of the screwed lower housing portion 14 along with its free lower end 117. This divider reduces pressure loss during operation on both the outlet and inlet sides of the rotary slide valve housing 46. In this process, the flow divider 116 is rotated to the center of the outlet 26 or inlet 24 in the open position.

[0045] The connection of the filter element 16 of the lower housing portion 12 to the upper end cap 40 will be described in more detail below, similar to the structure of the upper end cap 40.

[0046] In particular, as shown in Figures 7 and 8, the upper end cap 40 has a peripheral circular retaining ring 118 that is enlarged in diameter at its outer circumference. This retaining ring protrudes axially and radially beyond the element holder 120 on the ring side and serves to hold the upper free end face of the pleated element material 30, which is not shown in Figures 7 and 8 for simplification. The retaining ring 118 is integrally connected to the upper side 70 of the end cap 40 via diagonally extending retaining webs 122, and two diametrically opposed retaining webs 122 are provided with intersecting webs 124 for further reinforcement. The retaining ring 118, which has its webs 122 and 124, is in either case an integral part of the upper end cap 40, and an annular segmented flow path 126 is provided between the upper part 70 of the end cap 40 and the retaining ring 118, thereby allowing the unfiltered medium to flow from above through the fluid inlet 24 into the fluid chamber 28 having the filter element 16, and then from the outside to the inside through the element material 30, and the fluid flow flows from the fluid chamber 28 into the inside 32 of the filter element 16. The unfiltered medium flow then passes out through the element holder 120 in the hollow chamber between the cylindrical inside of the retaining ring 118 and the cylindrical outside of the upper element cap 40.

[0047] The retaining ring 118 preferably has at least one drive unit 128 at its downward-facing edge, and preferably two or three drive units 128 (Figure 6) extending equidistant from each other on the underside of the retaining ring 118. In particular, as shown in Figure 9, the lower housing portion 14 in the shape of the associated container has a rectangular recess 130 on its free upper end face, within which each drive unit 128 can be engaged from above in a precise fit. Once the retaining ring 118 is fully positioned above the lower housing portion 14, both friction lock and shape lock connections between the filter element 16 and the lower housing portion 14 are formed via the upper end cap 40 through the pair of drive units 128 in the recess 130. In this way, the filter element 16 can be driven in the same rotational direction as the lower housing portion 14 during both screw-in and screw-out operations. As shown in Figure 1, when the lower housing portion 14 is screwed into the functional or operating position, the retaining ring 118, having an upper end surface 132 and a lower end surface 134, contacts the adjacent wall of the upper housing portion 12 or the lower housing portion 14, respectively, and fixes its position. In this way, secure fastening and fixing of the filter element 16 in the operating position is achieved via the retaining ring 118 between the upper housing portion 12 and the lower housing portion 14.

[0048] Furthermore, as can be seen particularly in Figure 8, the socket joint 136 is provided concentrically with respect to the central opening of the element cap 40, and has a shell portion 138 which is rotatably guided within the shell holder 140 in the form of a spherical cap. The hollow cylindrical shell portion 136 has an annular sealing surface 144 at its center, on at least one retaining web 142 which is preferably annularly connected to the inside of the rotatable shell portion 138, and this annular sealing surface 144 forms a seal with the rotary slide valve housing 46, which is rotatable in the operating position, as soon as the rotary slide valve housing 46 makes contact with the upper side of the sealing ring 144 and its lower free edge 117 of the connector 114. For this purpose, the sealing ring 144 preferably has an inclined or roof-shaped sealing edge 146 which forms a seal with the free end face of the lower contact surface 117 of the connector 114 of the rotary slide valve housing 46 (Figure 5). The peripheral seal edge 146 is freely rotatable via the socket joint 136, i.e., the shell portion 138, which is rotatable within the shell holder 140 having its connection point 145, and is movably positioned so as to automatically adapt to the connection geometry of the connector 114 of the rotary slide valve housing 46. In this way, tolerance differences between the connector 114 and the seal ring 144 within the socket joint 136 can be compensated. Even if the connector 114 has an extreme inclination at its free lower end, as shown in Figure 2, the seal ring 144 can easily compensate for this difference via the socket joint 136, forming a securely sealed inner fluid passage 38 between the outlet side 26 of the filter device and the inside or filtration side 32 of the filter element 16 via the seal edge 146 of the seal ring 144. Furthermore, protection from counterfeits can be achieved by selecting an appropriate connection geometry on the control device 22 or on the rotary slide valve housing 46. This is not equivalent to the prior art.

Claims

1. A filter device comprising a filter housing (10) comprising at least an upper housing portion (12) and a lower housing portion (14) that at least partially resizablely receives a filter element (16), wherein the filter device comprises a control device (22) for controlling fluid flow in the upper housing portion (12), the control device (22) is controlled such that it disconnects a fluid connection between a fluid inlet (24) and a fluid outlet (26) in a shut-off position, and releases the fluid connection in an open position, and the control device (22) is controlled by an actuator (44) on the filter element such that the control device (22) moves to the shut-off position when the lower housing portion (14) is separated from the upper housing portion (12), and the open position is established when the lower housing portion (14) is attached to the upper housing portion (12), The control device (22) comprises a rotary slide valve housing (46) having at least one coupling element (48, 50), wherein the at least one coupling element (48, 50) cooperates with the corresponding coupling elements (54, 56, 58, 60) on the filter element (16) as an actuator (44) to form at least one coupling portion (52, 53), and when the lower housing portion (14) is attached or removed, at least one coupling element of the corresponding coupling elements (54, 56, 58, 60) drives into contact with one associated coupling element (48, 50) of the rotary slide valve housing (46) in each case, causing the rotary slide valve housing (46) to move from the closed position to the open position or from the open position to the closed position, and thereafter, when the rotary slide valve housing (46) is in either the open position or the closed position, the respective coupling portions (52, 53) are immediately released.

2. The filter device according to claim 1, wherein each of the connecting portions (52, 53) is configured in the form of a ratchet joint and has two adjacent opposing pairs of spring tongues as corresponding connecting elements (54, 60; 56, 58) on the end cap (40) of the filter element (16), which protrude in a manner that elastically yields into the travel path (72) of at least one control cam as one connecting element (48, 50) of the rotary slide valve housing (46).

3. The filter device according to claim 1 or 2, wherein the rotary slide valve housing (46) has two fluid passage points (76, 78) and two shut-off walls (80, 82), and the two shut-off walls (80, 82) can be moved to cover the fluid inlet (24) and the fluid outlet (26) in the open position or the shut-off position, respectively.

4. The filter device according to any one of claims 1 to 3, characterized in that the rotary slide valve housing (46) is guided by a sliding guide (88) in the upper housing portion (12) and has a further control cam (84) that restricts the movement of the rotary slide valve housing (46) between the shut-off position and the open position.

5. The filter device according to any one of claims 1 to 4, wherein a drive unit (128) is provided between the filter element (16) and the lower housing portion (14), and the drive unit (128) drives the filter element (16) received in the lower housing portion (14) along the same direction when relative movement occurs between the fixed upper housing portion (12) and the lower housing portion (14) which is movable toward the upper housing portion (12).

6. The filter device according to any one of claims 1 to 5, wherein the rotary slide valve housing (46) has an annular seal receptacle (90) on the side of the fluid outlet within the upper housing portion (12), and the annular seal seals the fluid transfer portion between the fluid outlet (26) and the inner fluid passage (38) within the rotary slide valve housing (46) in the open position.

7. The filter device according to any one of claims 1 to 6, characterized in that the inner fluid passage (38) penetrates perpendicularly within the rotary slide valve housing (46) and has a free end facing away from the fluid outlet (26) having a connecting inclined portion for fluid connection of the filter element (16) on the inside (32) of the inner fluid passage (38).

8. The filter device according to any one of claims 1 to 7, wherein the rotary slide valve housing (46) has a further inner fluid passage (39), and the further inner fluid passage (39) forms a fluid connection between the fluid inlet (24) and the fluid chamber (28) formed in the operating position by the filter element (16) and the lower housing portion (14) in the open position.

9. The filter device according to any one of claims 1 to 8, wherein the rotary slide valve housing (46) has at least one safety valve (100), and the at least one safety valve (100), in its shut-off position, opens when fluid flows through the rotary slide valve housing (46) from the fluid inlet (24) to the fluid outlet (26), opening the corresponding passage, bypassing the fluid chamber (28) in the lower housing portion (14), and preferably a contamination indicator (110) is connected in the corresponding passage.

10. The filter device according to any one of claims 1 to 9, wherein at least one bypass valve (102) is received within the rotary slide valve housing (46), and the at least one bypass valve (102), in the open position, opens the flow path between the fluid inlet (24) and the fluid outlet (26) during operation when the degree of contamination of the filter element (16) exceeds a predetermined level, thereby bypassing the filter element.

11. A filter element intended for use in a filter device according to any one of claims 1 to 10, wherein the filter element comprises an element material (30) having an end cap (40) on at least one free end face, A filter element characterized in that the end cap (40) comprises individual connecting elements (54, 56, 80, 60) that protrude outward as part of at least one connecting portion (52, 53).

12. The filter element according to claim 11, characterized in that the connecting elements (54, 56, 58, 60) of the end cap (40) are formed by at least one pair, preferably two pairs, of mutually adjacent and opposing spring tongues, each protruding inward by a predetermined distance along the movement path (72).

13. The filter element according to claim 11 or 12, characterized in that the movement path (72) is formed by shell-shaped guide surfaces (74) as part of the respective connecting portions (52, 53), the shell-shaped guide surfaces (74) protrude beyond the associated end caps (40), and in each case are formed at their ends by spring tongues.

14. The filter element according to any one of claims 11 to 13, characterized in that the shell-shaped guide surface (74) is outwardly surrounded by a retaining ring (118), the retaining ring (118) protrudes at least partially beyond the guide surface (74) when viewed from the axial direction, and is securely connected, preferably integrally connected, to the associated end cap (40) via webs (122, 124).

15. The retaining ring (118) protrudes beyond the edge of the end cap (40) and has at least one protruding drive portion (128) in the direction of the end cap (40), characterized in that the filter element is as described in any one of claims 11 to 14.

16. The filter element according to any one of claims 11 to 15, characterized in that a socket joint (136) is rotatably incorporated into the central opening of the end cap (40), and the socket joint has a connection point (145) that can be tilted in a predetermined direction to form a fluid passage (38) inside (32) of the filter element (16).

17. The filter element according to any one of claims 11 to 16, characterized in that the end of the element material (30) surrounds the socket joint (136) within the element holder (120) of the end cap (40).

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