Filter device and a filter element that can be accommodated therein, and a method for operating such a filter element and device - Patents.com

Abstract

1. A filter device comprising a filter housing 10, the filter housing having an inlet 12 for non-filtrate and an outlet 14 for filtrate, and accommodating a replaceable filter element 16, in which when the non-filtrate flows through the filter element from the outside to the inside, a hollow cylindrical element material 18 also flows through a element material 22 closing one free end 20 of the hollow cylinder 18, in which at the other free end 24 of the hollow cylinder, an element cap 26 having a central notch 28 is used to discharge the filtrate to the outlet 14 in the filter housing 10, the outlet being connected to the central notch 28, and in which the respective element materials 18, 22 are accommodated without seals in the filter housing 10 for flowing on all sides from the outside to the inside.

Description

[Technical field]

[0001] The present invention relates to a filter device having a filter housing having an inlet for unfiltrated liquid and an outlet for filtrate, and accommodating a replaceable hollow cylindrical filter element for allowing the unfiltrate to flow through from the outside to the inside. [Background technology]

[0002] A filter element considered as an exchange element of this kind is shown in WO 2018 / 082799, in which the element material formed as a hollow body and extending between two end caps is pleated with individual filter folds, and the element material has a filter material made of cellulose. When flowed through by a fluid, the cellulose fibers act to coalesce, thereby forming enlarged drops from the water component of the emulsion, which sink downward due to the difference in density between water and oil, so that separation of the less dense medium takes place. Such a filter element performs the mentioned water separation in a functionally more reliable manner and is also advantageously formed cost-wise.

[0003] This known filter element is fixed in an apparatus with a filter housing by means of a receiving rod as part of a fixing device, and each end cap of the filter element has a space holder with a sealing function on the one hand in the fixing device and on the other hand in the middle bottom of the filter housing. In this way, additional holding means extending beyond the outer periphery of the filter element are not necessary, which allows a space-saving construction.

[0004] From EP 3 334 512 an oil filtration unit for removing solid contaminants from contaminated oil is known, which comprises: - a housing having a housing inlet suitable for receiving contaminated oil from the environment and discharging the contaminated oil at a first pressure p1 to an opening in the interior of the housing, and a housing outlet suitable for discharging filtered oil to the environment; - an oil filter for filtering contaminated oil, the oil filter being arranged in an inner opening of the housing and having a filter inlet defined by an outer surface of the oil filter, an inner filter volume suitable for receiving filtered oil at a second pressure p2 (the second pressure p2 being lower than the first pressure p1) and a filter outlet inside the housing, the filter outlet forming a fluid / liquid connection between the inner filter volume and the housing outlet for discharging the filtered oil from the inner filter volume, an end plate of the oil filter having a filter outlet, the entire end plate having a porous material through which oil can escape, so that at least a portion of the end plate forms part of the filter outlet; and the filter outlet has a hydraulic resistance, which forms part of the oil filter, which hydraulic resistance forms a fluid / liquid flow boundary between the inner filter volume and the housing outlet, whereby a second pressure p2 inside the inner filter volume is increased and filtered oil is discharged from the inner filter volume into the housing outlet at a third pressure p3, which is lower than the second pressure p2.

[0005] The associated oil filter or filter element is of hollow cylindrical design and, in so far as such, is made of cellulose material. The disk-shaped end plate of the oil filter surrounds the filter outlet of the filter housing and can have a porous material made of natural or artificial polymers and cellulose material. This known filter element as an oil filter is passed through from the inside to the outside, and a hydraulic resistance is formed by the above-mentioned end plate made of a porous material, which in so far as serves as a flow boundary between the inner filter volume and the surroundings, so that the above-mentioned pressure stage p1>p2>p3 is obtained. The purpose of this pressure stage is thus to avoid back pressure for the filter element, which occurs, for example, when a hydraulic pump unit or the like is connected to the outlet side of the filter.

[0006] In addition to the flow from the outside to the inside, for the function it is necessary that the filter material on the bottom side of the filter element has a sealing device with respect to the filter housing to be accommodated, which firstly limits the effective surface area in the filter element and, on the other hand, leads to certain installation-technical expenditures in the filter housing. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2018 / 082799 [Patent Document 2] European Patent No. 3334512 Summary of the Invention [Problem to be solved by the invention]

[0008] Based on this prior art, the object of the present invention is to further improve the known solution, in such a way that the efficiency during filtration is improved, while retaining the advantages of the known solution, i.e. ensuring a functionally more reliable filtration drive, in a technically simple construction and in a cost-friendly manner. [Means for solving the problem]

[0009] This problem is solved by a filter device having the features of patent claim 1 as a whole and a filter element according to the features of independent patent claim 2 as well as a method for driving a filter element of this kind having the features of independent patent claim 12.

[0010] In the filter device according to the invention, when the replaceable filter element is passed through by the unfiltrated liquid from the outside to the inside, the hollow-cylindrical filter element and also the component material closing one free end of the hollow cylinder are passed through, and an end cap with a central cutout is used at the other free end of the hollow cylinder to discharge the filtrate to an outlet in the filter housing, which outlet is connected to the central cutout and each filter element is accommodated in the filter housing without a seal for passing through on all sides from the outside to the inside, resulting in a single pressure stage, in which the pressure p1 outside the filter element is greater than the discharge pressure p2 inside the component material closed in a hollow-cylindrical manner towards one side. It has been shown that this results in a substantially improved purification balance for the unfiltrated liquid flow and is energetically favorable, for which also contributes that the filtrate discharge side with the through discharge opening of the hollow-cylindrical component material is accommodated inside the filter housing, so that the passing through of the filter element from the bottom side to the head side takes place. The filtration direction for the filtrate flow, which thus rises to the discharge side with reduced pressure, is also advantageous in terms of the energy balance.

[0011] Since the component material of the filter element flows entirely from the outside to the inside, and therefore no additional sealing devices of the filter housing act on the filter element at the bottom side, the entire filter area is used for filtering, and the installation engineering effort and costs are reduced by eliminating such sealing devices.

[0012] The filter element according to the invention for the filter device, both within the hollow cylindrical component material and also the component material closing the hollow cylinder, is preferably made entirely of cellulose material, which is particularly advantageous when fine particulate dirt must be separated from the fluid flow, for example when oil deterioration products (varnish) are to be separated from the fluid flow, due to the homogeneous formation of the component material. The method according to the invention ensures such a filtering drive by means of the above-mentioned device and components, and on the basis of the pressure stage p1 present in one step in the direction of p2, reduces the flow resistance and achieves a high filtering output when using the method according to the invention.

[0013] In a particularly preferred embodiment of the filter element according to the invention, the hollow cylinder of the filter element is formed from individual, preferably identical, ring-shaped filter discs, which are firmly connected to one another at their adjacent front sides in an overlapping arrangement, preferably glued to one another, and the component material closing one free end of the hollow cylinder is formed from the closed filter discs. In this way, the filter element can be constructed in any length in a modular sense by passing through identical ring-shaped filter discs in an overlapping arrangement. Furthermore, the above-mentioned filter discs can be produced in large quantities as identical structural parts in the form of series production, which is cost-effective.

[0014] In another preferred embodiment of the filter element according to the invention, all filter discs made of cellulose material have the same filter properties, in particular the same filter fineness, and the ring-shaped filter discs are all constructed identically from the component material. The above-mentioned filter discs made of cellulose are produced according to the so-called Rapid Koethen Methode in accordance with DIN EN ISO 5269-2, so that as a standardized method a high process reliability is achieved in the production.

[0015] In another preferred embodiment of the filter element according to the invention, the ring-shaped filter discs here have cutouts on the outer periphery, which are formed by incisions or by spacers adjacent between the filter discs. The resulting cutouts firstly increase the stability of the sheet composite with the individual filter discs and allow a flow guidance for the unfiltrate flow through the filter element with the filter discs from the outside to the inside. In a preferred manner, the disc-shaped filter material closing the end side of the hollow cylinder can have an additional geometry, preferably in the form of an introduction device, which fits into the interior of the hollow cylinder. For the desired flow guidance in the interior of the hollow cylindrical filter element from the bottom side to the head side of the filter element, the introduction device can preferably have a trumpet shape from the outer periphery, the largest cross section of which transitions integrally into the component material of the closed filter disc. The introduction device also provides a certain resistance for the flow through the filter element on the bottom side of the component material, which leads to an improved flow through in the head region of the element and therefore to a uniform flow distribution in the filtration drive as a whole.

[0016] In another preferred embodiment of the filter element according to the invention, the hollow-cylindrical component material is accommodated between two end caps, one of which is formed as a double accommodation and is used to fasten the component material formed in a disk-shaped closed manner to the end of the ring-shaped component material. In this way, the hollow-cylindrical component material is separated from the disk-shaped component material by means of the double accommodation and replaced by a new component material, respectively. However, preferably, the disk-shaped component material is firmly bonded or welded to the hollow-cylindrical component material at the end side, so that the disk passes into the hollow cylinder without a gap. In this way, a uniform flow is obtained even in the joining area of ​​the disk-shaped component material and the hollow-cylindrical component material, and the filter element constructed in this way is replaced as a whole by an individual new component.

[0017] For a favorable flow guidance, moreover, the two end caps each have a central cutout, the diameters of which are equal and allow the filter element to be connected to the outlet of the filter housing, the diameter of the end caps having a diameter corresponding to the inner diameter of the hollow cylinder of the filter element. Especially the last-mentioned feature allows the filtrate to be discharged without resistance in the direction of the outlet of the filter device.

[0018] Particularly preferably, the closed disk-shaped component material is formed from a filter round blank, which comes from a sheet former, in particular a rapid Köthen sheet former which is available on the market.

[0019] In a preferred method of driving a filter element in a filter device as described above, the system is used to remove dirt, preferably varnish, from a fluid, the filter material being accommodated in a filter housing having an inlet for the unfiltrated liquid and an outlet for the filtrate, according to the invention, when the filter element is passed from outside to inside by the unfiltrate, the hollow cylindrical element material is passed through as well as the element material closing one free end of the hollow cylinder, the filtrate flow is guided from inside to outside of the hollow cylinder, and the respective element material is accommodated without a seal in the associated filter housing for circulation on all sides from outside to inside. Varnish is regularly listed in the literature as not being a "solid" particle and therefore is not a proper particulate dirt; rather, it is regularly a muddy oil deterioration product.

[0020] The cellulose used for the filter element may be constructed in the form of a composite cellulose, which may be combined with fillers, additives, filter aids, and the like.

[0021] As fillers, silicates such as kaolin, carbonates such as chalk, sulfates such as gypsum, barium sulfate, oxides such as titanium dioxide, aramid fibers and / or carbon fibers are regularly used. As additives, adhesives, bonding systems, dry and wet strengthening agents, pigments, dyes, dehydration and retention agents and defoamers are suitable. As filter aids, diatomaceous earth, diatomaceous gel, perlite, zeolite or activated carbon are used.

[0022] The solution according to the invention is explained in more detail below by means of an example. The figures are principle and not to scale representations: [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 shows the entire filter device in the form of a longitudinal section, which consists of a filter housing and a accommodated filter element. [Diagram 2]FIG. 2 shows the inserted filter element with arrows relating to the flow behavior of the filter element. [Diagram 3] FIG. 3 shows a second embodiment of the filter element in detail in longitudinal section. [Figure 4] FIG. 4 shows a filter element comparable to FIG. 3 in a side view looking from outside to inside. [Diagram 5] FIG. 5 shows a third embodiment of a filter member in a perspective view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] 1 shows the filter device according to the invention as a whole in a significantly simplified form in the form of a longitudinal section. The filter device has a filter housing 10 with an inlet 12 for the unfiltrated liquid and an outlet 14 for the filtrate. In the filter housing 10, a replaceable filter element 16 is accommodated, through which, according to the representation in FIG. 2, the unfiltrated liquid flows from the outside to the inside, through both a hollow-cylindrical filter material 18 and through a filter material 22 closing the free end 20 of the hollow cylinder 18. At the other free end 24 of the filter element 16 or of the hollow-cylindrical filter material 18, a filter cap 26 with a central recess 28 is provided, which serves to drain the filtrate and is connected to the outlet 14 of the filter housing 10. A similar central recess 29 is formed by the free end of the hollow cylinder 18 (FIG. 2).

[0025] To replace the filter element 16, the head-side housing part must be separated from the base-side or cup-side housing part with the filter element 16, which is typical and will not be mentioned in more detail here. The upper element cap 26 is put on via a short tube as part of the outlet 14 and is sealed on the housing side via a sealing ring 30 as the only seal between the element 16 and the housing 10 in this area. Besides, the respective element materials 18, 22 for flowing on all sides from the outside to the inside according to the representation shown in Fig. 2 are accommodated without sealing in the filter housing 10 as shown in Fig. 1. In particular, no seal is provided in the area of ​​the bottom side of the filter housing 10 opposite the element material 22 forming the end.

[0026] In the embodiment of the filter element 16 shown in Figures 1 and 2, the end-forming member material 22 is accommodated in a base or bottom end cap 32, which is made in the form of a double receptacle and serves at the same time to fasten the closed, disk-shaped member material 22 and the hollow-cylindrical member material 18. The accommodation of such member materials of the filter element 16 in end caps forming the end of the element is known, so this will not be mentioned in more detail here. The member materials 18, 22 of the filter element 16 are preferably constructed completely, and therefore both the hollow-cylindrical member material 18 and the closed, end-forming member material 22, consist of cellulose material. The term "closed" in the sense of the present application means that the end-forming member material 22 is made porous throughout, but does not otherwise have any fluid passages, such as, for example, throttle passages for conducting fluids, which could connect its periphery with the hollow-cylindrical interior 34 of the hollow cylinder 18. To that extent, the non-filtrate is admitted to the interior 34 of the element 16 only via the porosity of the filter material 22 for passage therethrough.

[0027] As the embodiment of Fig. 3 in particular shows, the hollow cylinder 18 of the filter element 16 is made up of individual, preferably equal, ring-shaped filter disks 16, which are firmly connected, preferably glued, to one another in an overlapping arrangement or in a stacked order with their adjacent front sides. In contrast to the embodiment shown in Fig. 2, the filter disk 36 arranged at the bottom in the direction of view of Fig. 3 is not accommodated in an additional end cap 32 as the component material 22 closing the free end of the hollow cylinder 18, but is instead firmly connected, in particular firmly glued or firmly welded, directly to the filter disk 36 located at the bottom of the hollow cylindrical component material 18 in the stacked order. The filter disk 36 arranged at the top forms a receiving space for the upper component cap 26 with a central cutout, the edge of which has a groove-shaped recess 40 for receiving the sealing ring 30 according to the representation of Fig. 1. The component cap 26 grips the outer periphery of the outer edge of the uppermost filter disc 38 and is firmly bonded thereto, for example using an adhesive bond.

[0028] 3, the individual filter disks 36 can also be formed from halves 36a, 36b, which between them, viewed perpendicularly to the longitudinal axis of the filter element 16, have identically formed cutouts 42, which are formed by cutting or stamping the filter disk 36 in the form of a notch or by the two filter disk halves 36a, 36b of the filter disk 36 being adjacent to each other. Furthermore, between the filter disks 36 in the stacking sequence, there are other similar cutouts 44 formed in the same way as the cutouts 42. Each cutout 42, 44 thus tapers in a wedge shape from a rectangular central area to the edge side of the respective filter disk 36 or the adjacently arranged disk half 36a, 36b. The above-mentioned cutouts 42, 44 in the form of cutouts or stampings are arranged only on the upper side of the respective component material 18, 22 and do not penetrate into the hollow cylindrical internal space 34 of the filter element 16. The possible flow directions of the filter element 16 are also indicated by arrows in FIG. 3, with the flow taking place from the bottom side towards the interior space 34 of the filter element 16 for the filter disc 36 which is located at the bottom in the stacking order.

[0029] In the modified embodiment shown in Fig. 4, the notches 42, 44 are formed by stamping or cutting into the corresponding circumferential side, in each case the notches 42, 44 serving to strengthen the overall stability of the cellulose element and to improve the flow guidance for the non-filtrate flow from the outside into the interior 34 of the filter element 16. In this case, in each filter disc 36 or between the disc halves 36a, 36b of the filter disc 36, respectively, there are four notches 42, 44 located in a common radial plane. The disc-shaped element material 22, formed in particular with its porosity closed, is formed from a filter round blank from a sheet former.

[0030] In the embodiment shown in FIG. 5, the individual disc halves 36a, 36b have defining bars as spacers 46 extending radially towards each other forming individual filter discs, which define between themselves notches 48 which again serve for improved fluid guidance but which again do not penetrate completely into the material to be filtered, comparable to the notches 42, 44 according to the previously described embodiment.

[0031] Furthermore, as shown in FIG. 1 by dashed lines, the interior space 34 can additionally, if necessary, have a flow guide or introduction device 50 which has a trumpet shape for improved flow guidance inside the filter element 16 and whose largest cross section transitions integrally into the material of the closed lower filter disk 36.

[0032] The solution according to the invention is used in particular to remove so-called varnishes, which are regularly formed from oil degradation products (which are not listed as "solid particles" in the literature and are therefore not particulate dirt in the proper sense) from fluid streams. Applications also concern dehydration, in particular cellulose has the property of being able to absorb water. In this way, oil-water separation is also achieved. Finally, there is also the possibility of particulate filtration.

Claims

1. 1. A filter device having a filter housing (10), the filter housing having an inlet (12) for non-filtrate and an outlet (14) for filtrate, and accommodating a replaceable filter element (16), in which when the non-filtrate flows through the filter element from the outside to the inside, a hollow-cylindrical element material (18) and also an element material (22) closing one free end (20) of the hollow-cylindrical element material (18) flow through, and at the other free end (24) of the hollow-cylindrical element material (18) an element cap (26) having a central notch (28) is used to discharge the filtrate to the outlet (14) in the filter housing (10), the outlet being connected to the central notch (28), and each of the element materials (18, 22) is accommodated without a seal in the filter housing (10) for flowing on all sides from the outside to the inside.

2. 2. A filter element for a filter device according to claim 1, comprising a hollow cylindrical member material (18), the member material being provided at its free front side (20) with a member material (22) closing the hollow cylindrical member material (18), A filter element, characterized in that each of said element materials (18, 22) consists at least partly, preferably entirely, of a cellulose material.

3. the hollow cylindrical member material (18) of the filter element (16) is formed from individual, preferably equal, ring-shaped filter discs (36), said filter discs being rigidly connected to one another at their adjacent front sides in an overlapping arrangement, preferably glued to one another; and 3. A filter element according to claim 2, characterized in that the member material (22) closing one end of the hollow cylindrical member material (18) is formed from a closed filter disc (36).

4. all filter discs (36) made of cellulose material have the same filtering properties; and 4. A filter element according to claim 3, characterized in that the ring-shaped filter discs (36) are all constructed identically from the filter material.

5. A filter element as described in claim 3, characterized in that each of the ring-shaped filter discs (36) has a notch (42, 44, 48) on its outer periphery, the notch being formed by cutting, engraving or by adjacent space holders (46) between the filter discs (36a, 36b).

6. A filter element as described in claim 2, characterized in that the disk-shaped filter element (22) is provided with an additional geometric arrangement in the form of an introduction device (50), which fits into the interior (14) of the hollow cylindrical element material (18).

7. 7. The filter element according to claim 6, characterized in that the introduction device (50) has a trumpet shape from its outer periphery, the largest cross section of which merges integrally into the component material (22) of the closed filter disc (36).

8. 3. The filter element according to claim 2, characterized in that the hollow cylindrical component material (18) is housed between two end caps (26, 32), one of which (32) is formed as a double housing and is simultaneously used to fasten the component material (22) formed in a closed disk shape to an end of the hollow cylindrical component material (18).

9. the two end caps (26, 32) each have a central notch (28, 29) the diameters of which are equal; and 9. The filter element of claim 8, wherein the end cap (26) capable of connecting the filter element (16) to the outlet (14) of the filter housing (10) has a diameter substantially equal to an inner diameter of the hollow cylindrical member material (18) of the filter element (16).

10. A filter element as described in claim 2, characterized in that the closed disc-shaped element material (22) is formed from a filter round blank.

11. 11. The filter element according to claim 10, wherein the filter round blank is made by a sheet former.

12. 12. A method for driving a filter element according to any one of claims 2 to 11 in a filter device according to claim 1, said method being used for removing dirt, preferably varnish, from a fluid stream and being contained in a filter housing (10) having an inlet (12) for non-filtrate and an outlet (14) for filtrate, comprising: When the unfiltered liquid flows through the filter element (16) from the outside to the inside, the unfiltered liquid also flows through the hollow cylindrical element material (18) and through the element material (22) closing one free end of the hollow cylindrical element material (18), the filtrate flow is directed from the inside of the hollow cylindrical member material (18) to the outlet (14) of the filter housing (10); and 2. A method according to claim 1, characterized in that the respective component materials (18, 22) are accommodated without seals in said filter housing (10) for circulation on all sides from the outside to the inside.

Images