Laundry machine effluent filtration using an agitator rotating around a filter element

Abstract

The invention relates to a rotor-assisted filter for filtering effluent of a washing machine. The rotation of the rotor supports centrifugal separation of particularly heavy particles and fibers. Filter elements are engaged into the rotor, particularly between axially extending vanes of the rotor. The filter elements can separate microplastics from the effluent. A receptacle surrounds the filter elements. Fibers, particles and microplastics are collected in the receptacle. For cleaning, the filter elements and the receptacle can be removed from the filter housing. Preferably, the receptacle is detachable from the filter elements. Sliding the receptacle along the filter elements can wipe off debris from the filter elements.

Description

Technical Field

[0001] This invention relates to a filter assembly comprising: -case; - Filter elements; - A rotor, which is rotatably mounted inside the housing and includes at least one blade. Background Technology

[0002] This filter component is known from the article "Filtersysteme für den Einsatz inanspruchsvollenAnwendungen – Auf den Prozess abgestimmt", which was published online on June 7, 2022 at https: / / prozesstechnik.in.dustrie.de / chemie / schuettguttechnik-chemie / auf-den-prozess-abgestimmt / and last accessed on September 29, 2023.

[0003] When clothes are washed, fibers and lint are released. Because clothing is often made of synthetic fibers, a certain amount of microplastics is generated during each wash cycle. Today, microplastic emissions are often considered a serious ecological problem.

[0004] If fibers and microplastics should not be released into the environment, they need to be intercepted for proper disposal. The use of filters for this purpose is generally known, for example, from WO 2021 / 070102 A1.

[0005] The article cited at the beginning describes a filter element used to filter process fluids from industrial equipment, in which a dynamic scraper moves around the filter element, which additionally rotates the liquid to be filtered. Due to centrifugal force, contaminant particles are transported from the filter element toward the housing wall and continuously discharged downwards. The hydrodynamic scraper also generates negative pressure and thus creates unstable flow conditions at the surface of the filter element. This enhances the filtration effect. Together, these two effects prevent the formation of a filter cake on the filter surface.

[0006] WO 2021 / 070102 A1 discloses a filter assembly including an inertial separator as a first filtration stage for removing the largest and heaviest particles. The inertial separator is formed by a tangential inlet and a cylindrical inner wall of a container that rotates the incoming effluent, throwing larger debris to the outside of the container under centrifugal force, where the debris settles to the bottom of the container. A second filtration stage of the filter assembly includes a cylindrical coarse mesh.

[0007] The purpose of this invention is to provide a highly efficient and easy-to-clean filter for the effluent from a washing machine.

[0008] This is achieved through the use of the filter assembly according to claim 1, the filter assembly according to claim 14, and the washing machine according to claim 15. Advantageous embodiments are given in the dependent claims and the specification. Summary of the Invention

[0009] According to the present invention, a filter assembly for filtering the effluent from a washing machine is provided. The effluent may also be referred to as wastewater. The effluent generally contains soil and material of clothing that has been washed from clothes and the like, particularly fibers and debris, which may contain microplastics.

[0010] The filter assembly includes a housing. An inlet for the outflow from the washing machine drum is typically located at the upper end of the housing. An outlet for filtered wastewater (i.e., wastewater containing fewer fibers and particles than the outflow from the drum) is typically located at the lower end of the housing.

[0011] The filter assembly also includes a filter element having a cylindrical filter media body. Preferably, the filter media body is a filter screen. The maximum pore size of the filter media body can be 150 μm, or 10 μm, preferably 50 μm, and particularly preferably 20 μm. The filter element prevents particles such as microplastics from moving forward to the outlet. During use, water passes through the filter media body radially inward.

[0012] The rotor of the filter assembly is rotatably mounted inside the housing. The rotor may also be referred to as an agitator. The rotor includes at least one blade extending along the filter element. The blade may extend parallel to or oblique to the axis of rotation of the rotor. Typically, the rotor includes at least two blades. The rotor may particularly include four or five blades. All blades may have the same cross-sectional shape. Alternatively, at least one of the blades may have a cross-sectional shape different from that of at least one of the other blades.

[0013] During use of the filter assembly, the rotor rotates around the filter media body. The rotation of the rotor causes the effluent to swirl inside the housing. Due to centrifugal force, some particles travel towards the circumferential wall of the housing. These particles generally sink downwards along the circumferential housing wall. The rotating blades can further generate pressure waves and / or locally alternating flow directions, particularly towards the radially inward or outward direction. This helps to permanently clean the filter media body and prevent clogging.

[0014] The rotor's axis of rotation generally coincides with the axis of the filter media. Directional indications, such as radial, axial, or circumferential, are generally referenced to the axis of rotation, particularly the common axis. During use, the axis of rotation, particularly the common axis, is oriented approximately vertically, for example, with a maximum inclination of up to 20°, preferably up to 10°, towards a vertical axis.

[0015] According to the present invention, the filter assembly includes a reservoir located at the bottom end of the filter element. The reservoir is used to collect particles that have been separated from the effluent by centrifugal force and by the filter element.

[0016] Preferably, the housing engages around the filter element. The housing may be cup-shaped and include an outer wall and a lower surface. Advantageously, the housing is rotationally symmetrical about the axis of the filter element. The housing is typically arranged above the outlet of the housing.

[0017] Furthermore, according to the invention, the filter element and the housing are detachably arranged inside the housing. This allows the filter element and the housing to be removed from the housing for cleaning. With the filter element and the housing separated from the housing, accumulations of contaminants containing microplastics or the like can be wiped out from the housing for proper disposal. After cleaning, the filter element and the housing are repositioned in the housing for further use of the filter assembly.

[0018] Apart from the inlet and outlet, the housing is largely closed during the use of the filter assembly. In particular, there is no waste outlet at the housing. Instead, as described previously, particles, fibers, etc., are collected in the reservoir and disposed of during maintenance.

[0019] The filter element may include a support body around which a filter media body is joined. The support body provides stability to the filter media body. Preferably, the support body includes longitudinal ribs and circumferential ribs. This design keeps a large open area of ​​the filter media body for filtration while providing sufficient stability.

[0020] The support may include end plates that seal the housing in the assembled state. This design reduces the number of parts that need to be handled during maintenance. In particular, a separate cover for the housing is not required because the end plates of the support are used to close the insertion opening of the housing. Preferably, the end plates and the housing include mating threads. This facilitates assembly and disassembly while ensuring a secure connection. Sealing elements (such as O-rings) may be arranged between the housing and the end plates. This further reduces the risk of leakage.

[0021] The support may have a shoulder for sealing abutment against the reservoir (preferably the lower surface of the reservoir). The shoulder defines the position of the reservoir in its installed state. Furthermore, the shoulder facilitates sealing the reservoir against the support to prevent water containing debris from bypassing between the reservoir and the filter element.

[0022] The support body may have a flow opening (flow window) arranged below the shoulder. The flow opening allows filtered water to drain radially inward from the filter media body toward the outlet. The flow opening may be specifically positioned between the shoulder and the end plate.

[0023] Preferably, the reservoir is detachable from the filter element. This allows the reservoir to be removed from the filter element for cleaning.

[0024] The housing can slide along the filter element, preferably with its inner edge abutting the filter element. Intuitive sliding movement is achieved without the need for disassembly and assembly tools. Furthermore, the inner edge of the housing sliding along the filter element scrapes debris from the filter media body during disassembly. Therefore, thorough cleaning can be achieved with minimal and simple manipulation. Preferably, the inner edge is located at the lower surface of the housing, which can seal against the shoulder of the support body in the installed state.

[0025] The housing may have an inwardly projecting edge for a sealing abutment against the upper edge of the outer wall of the reservoir. This prevents water containing debris from bypassing between the housing and the reservoir. Furthermore, the edge provides an upper stop for the reservoir. Specifically, the reservoir can be clamped between the edge of the housing and the shoulder of the support in the assembled state. Therefore, mispositioning of the reservoir is reliably prevented.

[0026] The rotor may have a shaft that protrudes through the upper end wall of the housing. Preferably, the shaft is rotatably mounted on the upper end wall. This design can employ standard bearings or bushings. Furthermore, the protruding shaft facilitates the attachment of a motor for driving the rotor.

[0027] The filter assembly may also include a motor, particularly an electric motor, for rotating the rotor. Preferably, the motor is attached to an extension shaft of the rotor. The motor allows the rotor to be driven independently of the washing machine's pump. In other words, a specific rotational speed of the rotor can be obtained, regardless of the flow rate of water through the washing machine.

[0028] At least one of the rotor blades may have a tapered cross-section. Preferably, the radial width of the blade decreases circumferentially over at least half of its circumferential extension. In particular, the blade may be configured with an airfoil profile. As the rotor rotates, the tapered cross-section of the rotating blades generates varying pressure and / or flow direction around the filter media. In other words, waves can be generated in the water. For example, a radially inward flow pattern can be established at the leading edge of the blade, while a radially outward flow pattern can be established at the trailing edge. This helps prevent clogging of the filter media and facilitates the removal of fibers or particles from the filter media.

[0029] At least one of the rotor blades can have a cross-section with a constant radial width. This design can save on manufacturing costs.

[0030] Preferably, blades with different cross-sections are arranged at the rotor. This results in different flow patterns, which can lead to particularly efficient cleaning and clogging prevention of the filter element during normal use.

[0031] The rotor may include a flange having at least one axially inclined rib. Preferably, several inclined ribs are provided at the flange. In the assembled state, the flange is arranged substantially adjacent to the housing. As the rotor rotates, at least one inclined rib, also referred to as the inclined edge, pushes water downward into the housing. In other words, the flange having at least one inclined rib functions as an axial flow fan.

[0032] One or more inclined ribs preferably project radially outward at the flange. Therefore, a downward flow pattern is established, particularly adjacent to the circumferential shell wall, where heavier particles accumulate due to centrifugal force.

[0033] The present invention also relates to the use of a filter assembly according to the invention, as described above, for filtering the effluent from a washing machine. This reduces the ecological impact of operating the washing machine.

[0034] The present invention also relates to a washing machine comprising a filter assembly according to the invention as described above. During washing machine operation, a smaller amount of particles (such as microplastics) are fed into the wastewater system. A washing machine typically includes a water inlet for receiving clean water, a washing drum, and a water outlet for discharging wastewater. Preferably, the filter assembly is fluidly arranged between the washing drum and the water outlet. In other words, the effluent from the washing drum is guided through the filter assembly before being discharged via the water outlet. Attached Figure Description

[0035] Other advantages and features of the invention will be appreciated from the following description of embodiments of the invention, which shows important details in the accompanying drawings and claims. The various features described above or explained below can be implemented individually or together in any useful combination in variations of the invention.

[0036] Figure 1 A schematic sketch illustrates a washing machine according to the invention, including a filter assembly according to the invention; Figure 2 A filter assembly according to the invention is shown in a schematic perspective view; Figure 3 A schematic longitudinal section is shown from Figure 2 Filter components; Figure 4 A schematic partial cross-sectional view is shown from Figure 2 The filter assembly, wherein the filter element and housing are removed from the housing; Figure 5 A schematic perspective view shows the situation when the container is removed. Figure 2 Filter elements of a filter assembly; Figure 6 A schematic perspective view shows the source Figure 2 The rotor of the filter assembly; Figure 7 A schematic cross-sectional view is shown. Figure 6 The rotor. Detailed Implementation

[0037] Figure 1 A washing machine 10 is shown. The washing machine 10 includes a rotatable drum 12 for receiving clothes or similar items to be washed. Fresh water is fed into the drum 12 via a water inlet 14 of the washing machine 10. Wastewater (outflow) from the drum 12 is discharged into a wastewater system (not depicted) via a water outlet 16 of the washing machine 10. A filter assembly 20 is fluidly arranged between the drum 12 and the water outlet 16. The filter assembly 20 may be arranged on the outside of the washing machine 10, such as... Figure 1 As depicted, or may be arranged within the housing of the washing machine 10 (not depicted). The filter assembly 20 prevents debris that may contain microplastics from being fed into the wastewater system.

[0038] Figure 2 and Figure 3 A filter assembly 20 of a washing machine 10 is shown. The filter assembly 20 includes a housing 22 having a cylindrical circumferential wall 24. In the depicted embodiment, the upper end wall 26 of the housing 22 is screwed into an upper housing portion 28, which is then connected to the upper end of the circumferential wall 24. A lower housing portion 30 is connected to the lower end of the circumferential wall 24. An inlet 32 ​​of the filter assembly 20 is formed at the upper housing portion 24. The inlet 32 ​​tangentially guides the fluid flow into the housing 22. Advantageously, an initial centrifugal force is generated for the wastewater. The wastewater can rotate at least partially around and outside the filter media body 50 under the action of the initial centrifugal force. The initial centrifugal force is supplemented by the rotation of the rotor 66, which is further described below. An outlet 34 of the filter assembly 20 is formed at the lower housing portion 30.

[0039] Filter element 36 and housing 38 are detachably mounted in housing 22, see also Figure 4 The housing 38 is detachably arranged on the filter element 36, see also Figure 5 .

[0040] Filter element 36 includes a support 40, specifically referenced to Figure 3The support body 40 has an end plate 42 that, in the assembled state, closes the housing 22 at its lower end. The end plate 42 and the lower housing portion 30 include mating threads 44a, 44b to establish a detachable connection. A sealing element 45 may be disposed between the end plate 42 and the lower housing portion 30. The end plate 42 may be provided with a tool interface 43 or have a grip (not depicted) for tool-free disassembly and assembly.

[0041] The grid section of the support 40 protrudes axially from the end plate 42 into the housing 22. The grid section includes longitudinal ribs 46 and circumferential ribs 48. A cylindrical filter media body 50 made of filter screen surrounds the grid section.

[0042] A flow opening 52 is formed between the grid section and the end plate 42 of the support 40. A fluid connection is established between the clean side (i.e., the radial internal volume of the filter media body 50) and the outlet 34 through the flow opening 52.

[0043] A circumferential shoulder 54 is formed between the flow opening 52 and the grille section. In the assembled state, the receiving seat 38 is mounted on the shoulder 54.

[0044] The housing 38 is rotationally symmetrical and includes a lower surface 56 and an outer wall 58, the outer wall 58 protruding from the lower surface 56 and extending upward.

[0045] The lower surface 56 of the housing 38 seals against the support 40. Specifically, the inner edge 60 of the lower surface 56 tightly mates with the support 40 and the filter media body 50. When removing the housing 38 from the filter element 36 during maintenance, refer to... Figure 5 The inner edge 60 scrapes particles and fibers from the filter media body 50. As the container 38 slides along the filter media body 50, these residues are automatically collected in the container 38.

[0046] In the assembled state, the upper edge 62 of the outer wall 58 seals against the inwardly projecting edge 64 of the housing 22.

[0047] Therefore, through the contact between the reservoir 38 and the housing 22 and the support 40, the reservoir 38 prevents fluid from flowing directly from the inlet 32 ​​to the outlet 34. Instead, water is forced through the filter media body 50, which prevents fibers, particles, and especially microplastics from passing through. This flow path is... Figure 3 The middle is indicated by arrow 65.

[0048] The filter assembly 20 also includes a rotor 66. The rotor 66 is mounted inside the housing 22 and engages around the filter media body 50. A shaft 68 of the rotor 66 protrudes through the upper end wall 26 of the housing 22. Seals and bearings or bushings may be disposed between the shaft 68 and the upper end wall 26. The axis of rotation of the rotor 66 coincides with the axis of the cylindrical filter media body; the common axis is identified by the numeral 70. A motor 72 for rotating the rotor 66 may be attached to the free end of the shaft 68, see reference. Figure 1 .

[0049] Rotor 66 assists in separating particles from wastewater received via inlet 32. Furthermore, rotor 66 prevents clogging of the filter media. Rotor 66 includes a plurality of blades 74, 76 extending along the filter media body 50, see in particular... Figure 6 and Figure 7 In this embodiment, blades 74 and 76 extend parallel to axis 70.

[0050] During operation, the rotating blades 74 and 76 cause the water on the outer side of the filter media body 50 to rotate around axis 70. This causes particularly heavy particles 78 to travel towards the circumferential wall 24, where they settle into the reservoir 38. Figure 3 Note that the size of particle 78 is... Figure 3 The claim is exaggerated.

[0051] In the depicted embodiment, the two blades 74 have a constant radial width 80, referenced Figure 7 .

[0052] The two blades 76 have a tapered cross-section and may resemble airfoils. The radial width 82 of the blades 76 decreases from their leading edge 84 toward their trailing edge 86. The arrow indicates the direction of rotation 88 of the rotor 66.

[0053] At the leading edge 84 of the blade 76, the rotation of the rotor 66 supports the inward flow of water through the filter media body 50. At the trailing edge 86, the rotation of the rotor 66 can cause a partial reversal of the flow pattern, i.e., water can be drawn back outward. This partial backflushing can release particles and fibers that may adhere to the filter media body, allowing them to settle into the container 38.

[0054] A circumferential flange 90 is provided at the lower end of the rotor 66. Blades 74 and 76 are each connected to the flange 90. The flange has outwardly projecting ribs 92 (which may be referred to as blades), which are inclined relative to the axis 70. When the rotor 66 rotates, the axially inclined ribs 92 push water and debris into the reservoir 38. Because the reservoir 38 is open to the filter media body 50, water can pass from the reservoir 66 through the filter media body 50, while debris is retained in the reservoir 38.

[0055] In general, the present invention relates to a rotor-assisted filter for filtering the effluent from a washing machine. The rotation of the rotor supports the centrifugal separation of particularly heavy particles and fibers. A filter element is engaged in the rotor, particularly between the axially extending blades of the rotor. The filter element separates microplastics from the effluent. A reservoir surrounds the filter element. Fibers, particles, and microplastics are collected in the reservoir. For cleaning, the filter element and reservoir can be removed from the filter housing. Preferably, the reservoir is detachable from the filter element. Debris can be wiped away from the filter element by sliding the reservoir along the filter element.

[0056] List of reference numerals Washing machine 10 Roller 12 Water inlet 14 Water outlet 16 Filter assembly 20 Casing 22 Zhou Xiangbi 24 Upper wall 26 Upper shell portion 28 Lower housing part 30 Entrance 32 Exports 34 Filter element 36 Seat 38 Support 40 End plate 42 Threads 44a and 44b Sealing element 45 Longitudinal rib 46 Zhou Xianglai s 48 Filter media 50 Flow opening 52 Shoulder 54 Lower face 56 Outer wall 58 Inner edge 60 Top edge 62 Edge 64 Arrow 65 Rotor 66 Shaft 68 Axis 70 Motor 72 Leaflets 74, 76 Particle 78 Radial width 80, 82 Leading edge 84 Back edge 86 Rotation direction 88 Flange 90 Inclined Rib 92

Claims

1. A filter assembly (20) for filtering effluent from a washing machine, the filter assembly (20) comprising: -Shell (22); - Filter element (36), the filter element (36) having a cylindrical filter media body (50), particularly a filter screen; - Rotor (66), rotatably mounted inside the housing and including at least one blade (74, 76) extending along the filter media body (50); and - Container (38), the container (38) is located at the bottom end of the filter element; in, The filter element (36) and the housing (38) are detachably arranged inside the housing.

2. The filter assembly (20) according to claim 1, wherein, The filter element (36) includes a support (40) around which a filter media body (50) is joined, preferably wherein the support (40) includes longitudinal ribs and circumferential ribs (46, 48).

3. The filter assembly (20) according to claim 2, wherein, The support (40) includes an end plate (42) that seals the housing (22) in the assembled state. Preferably, the end plate (42) and the housing include mating threads (44a, 44b).

4. The filter assembly (20) according to claim 2 or 3, wherein, The support (40) has a shoulder (54) for sealing contact with the lower surface (56) of the receiver (38).

5. The filter assembly (20) according to claim 4, wherein, The support (40) includes a flow opening (52) disposed below the shoulder (54).

6. The filter assembly (20) according to any one of the preceding claims, wherein, The housing (38) can be detached from the filter element (36).

7. The filter assembly (20) according to claim 6, wherein, The container (38) is slidable along the filter element (36), preferably wherein the inner edge (60) of the container (38) abuts against the filter element (36).

8. The filter assembly (20) according to any one of the preceding claims, wherein, The housing (22) has an inwardly projecting edge (64) for sealing abutment against the upper edge (62) of the outer wall (58) of the housing (38).

9. The filter assembly (20) according to any one of the preceding claims, wherein, The rotor (66) has a shaft (68) that protrudes through the upper end wall (26) of the housing (22).

10. The filter assembly (20) according to any one of the preceding claims further includes a motor (72), particularly an electric motor, for rotating the rotor (66), preferably wherein the motor (72) is attached to the protruding shaft (68) of the rotor (66).

11. The filter assembly (20) according to any one of the preceding claims, wherein, At least one of the blades (76) has a tapered cross section, preferably wherein the radial width (82) decreases in the circumferential direction over at least half of the circumferential extension of the blade (76).

12. The filter assembly (20) according to any one of the preceding claims, wherein, At least one of the blades (74) has a cross section with a constant radial width (80).

13. The filter assembly (20) according to any one of the preceding claims, wherein, The rotor (66) includes a flange (90) having at least one axially inclined rib (92).

14. Use of the filter assembly (20) according to any one of claims 1 to 13 for filtering the effluent from the washing machine (10).

15. A washing machine (10) comprising a filter assembly (20) according to any one of claims 1 to 13.

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