An under-the-sink water filter and a control method thereof

Abstract

The application provides a kitchen wastewater filter and a control method thereof, and relates to the technical field of filters. The kitchen wastewater filter comprises a connecting head and a filter core. The bottom of the connecting head is provided with a containing cavity with a spiral guide groove and water inlet and outlet ports. The top end of the filter core is provided with a stepped joint, the outer peripheral wall of which is provided with a screw joint clamping half, and the joint is provided with at least two radial platforms with radial sealing elements. When the filter core is rotated and locked, the screw joint clamping half slides along the spiral fitting surface to drive the axial displacement of the joint, so that the sealing elements form an interference fit. When the locking terminal position is reached, the water inlet and outlet ports are in communication with the filter core channel. The application converts the rotary torque into axial thrust through spiral fitting, reduces the installation resistance, realizes single-hand quick disassembly, cooperates with the multi-stage stepped sealing structure, ensures the accurate alignment of the waterway and the two-stage physical isolation, and uses mechanical limiting to eliminate the collapse or water leakage hidden danger caused by improper installation, and significantly improves the sealing reliability.

Description

Technical Field

[0001] This invention relates to the field of filter technology, and more specifically, to a sink drain filter and its control method. Background Technology

[0002] Under-sink water filters are typically installed in narrow cabinets under the kitchen sink to filter kitchen water. Their filter cartridges are consumables that need to be replaced periodically. Due to the limited space under the sink, large blind spots, and inconvenient operating posture, the connection and replacement structure of the filter cartridges places high demands on ease of operation, reliable sealing, and prevention of misinstallation.

[0003] Currently, most common under-sink water filter connection structures use threaded screw connections or snap-on quick-installation methods. Threaded screw connections require rotating the filter element multiple times along the threads to complete installation and sealing, which is extremely inconvenient in confined spaces, especially when the filter element is wet and slippery, making it difficult to apply force with one hand. Furthermore, during tightening, the sealing ring rubs and twists synchronously with the threaded surface, easily becoming damaged due to excessive local compression or twisting, leading to seal failure and leakage. While snap-on quick-installation structures reduce the number of rotations to some extent, their locking and sealing actions are usually separate—axial positioning is often achieved first through the snap, followed by an additional clamping mechanism or manual pressing to position the seal. This cumbersome installation process easily leads to false locking or the safety hazard of water flowing through before the seal is properly tightened.

[0004] Furthermore, with existing connection structures, after locking, the connection between the inlet / outlet and the internal flow channel of the filter element often requires additional alignment confirmation by the operator. If water is forced through when the flow channel is not aligned, not only will normal filtration fail, but the filter element or connector may even be damaged due to pressure buildup. More critically, the rotational torque applied by the operator in traditional structures is mainly used to overcome thread friction or snap-fit ​​resistance, and it is difficult to reliably convert it into axial clamping force that meets sealing requirements. Over-tightening often leads to plastic deformation of the seal, while over-tightening often results in leakage at the sealing interface. There is a lack of repeatable and controllable pre-tightening methods for the seal.

[0005] The aforementioned problems result in existing under-sink water filters relying heavily on operator experience and feel during filter replacement, making it difficult to guarantee installation consistency and sealing reliability. This is incompatible with the development trend of tool-free, error-proof, and quick-replacement under-sink equipment. Therefore, there is an urgent need for an under-sink water filter connection solution that can simultaneously complete locking, sealing, and flow channel opening in a single, small-angle rotation operation, and can stably convert rotational torque into the axial clamping force required for sealing. Summary of the Invention

[0006] The technical problem to be solved by the present invention is how to achieve reliable locking, sealing and pressing of the filter element and precise conduction of the inlet and outlet water channels simultaneously through a single, small-angle rotation operation, and to stably convert the rotational torque into the axial pressing force required for sealing. In order to overcome the above-mentioned defects of the prior art, the present invention provides an under-sink water filter and its control method.

[0007] This invention provides an under-sink water filter, including a connector and a filter element; The connector has a receiving cavity at the bottom, and a spiral guide groove is formed on the inner peripheral wall of the receiving cavity. The lower groove wall of the spiral guide groove forms a spiral mating surface. The connector is provided with an inlet port and an outlet port leading to the receiving cavity. The filter element has a stepped connector at the top, and the outer peripheral wall of the stepped connector has a screw-fitted flap that matches the spiral guide groove. The filter element has an inlet channel and an outlet channel. The stepped connector has at least two radial platforms from top to bottom, and each radial platform has a radial seal. When the filter element is rotated and locked, the screw-on clip slides and rises along the spiral mating surface, causing the stepped connector to move upward axially, so that the radial seal and the inner wall of the accommodating cavity form an interference fit; when the screw-on clip reaches the locking end position of the spiral guide groove, the water inlet port is connected to the water inlet channel, and the water outlet port is connected to the water outlet channel.

[0008] Compared with existing technologies, the under-sink water filter disclosed in this application has the following advantages: Through the cooperation of the spiral guide groove and the screw-on locking flap, the circumferential rotational torque is converted into axial clamping thrust, significantly reducing the force threshold required to overcome sealing resistance. This allows users to easily complete quick disassembly and assembly with one hand in the narrow and obstructed space under the sink. Simultaneously, combined with the multi-stage stepped radial sealing structure of the connector from top to bottom, when the locking flap slides along the spiral surface to the locking terminal position, it can achieve precise alignment of the inlet and outlet water paths and double-stage radial interference clamping, physically isolating raw water and pure water to prevent cross-contamination. Furthermore, the mechanical terminal limiting mechanism ensures absolute consistency between physical locking and water flow, eliminating the risk of detachment or leakage caused by improper blind installation from the structural root, significantly improving the overall sealing reliability of the system and the user maintenance experience.

[0009] In one possible implementation, a limiting block is provided at the end of the spiral guide groove. When the screw-on clip slides along the spiral mating surface to abut against the limiting block, it is stopped to limit the rotation stroke of the filter element.

[0010] Compared with existing technologies, the limit stop can provide a definite rotation stop point when the screw-on clip arrives, preventing excessive twisting from damaging the seal, while ensuring that the filter element stops precisely in the preset locking position, thereby reliably achieving accurate alignment and sealing with the inlet and outlet water channels.

[0011] In one possible implementation, the angle between the helical mating surface and the horizontal plane is 5° to 15°; the top surface of the screw-on latch is provided with an inclined guide surface that is consistent with the slope of the helical mating surface.

[0012] Compared with existing technologies, this angle range and the matching inclined guide surface can smoothly and linearly convert the rotational operating force into axial clamping force, reducing operating resistance while ensuring uniform pressure on the radial seal, thus avoiding seal failure or screwing sticking caused by local stress concentration.

[0013] In one possible implementation, the stepped connector includes a first radial platform and a second radial platform arranged from top to bottom, the water inlet channel is located at an eccentric position of the stepped connector, and the water outlet channel is located at the center position of the stepped connector; the radial seal includes a first radial seal disposed on the first radial platform and a second radial seal disposed on the second radial platform, the first radial seal physically separating the water inlet channel and the water outlet channel in the radial direction.

[0014] Compared with existing technologies, by using a combination of graded isolation of double-layer radial seals and eccentric / central flow channel layout, independent inlet and outlet flow channels are constructed within the narrow space of the stepped joint. This not only prevents media leakage outside the joint surface, but also structurally eliminates the risk of cross-contamination between inlet and outlet water inside the joint, significantly improving sealing reliability and isolation.

[0015] In one possible implementation, the connector is fitted with an anti-slip cover, the outer surface of which is integrally formed with interwoven anti-slip patterns.

[0016] Compared with existing technologies, the combination of the anti-slip outer cover and the one-piece molded interwoven texture increases the frictional resistance between the palm and the outer cover when manually turning, making it easier to hold the connector stably in wet, slippery, and confined under-sink environments, thereby reliably applying reverse support force to complete the filter cartridge installation and removal operations.

[0017] In one possible implementation, the filter element has a central guide tube axially arranged inside. The upper end of the central guide tube is sealed and connected to the water outlet channel, and the lower end penetrates the filter medium area of ​​the filter element and extends to the bottom of the inner cavity of the filter element.

[0018] Compared with existing technologies, by setting a central guide pipe and extending the outlet to the bottom of the filter element cavity, the raw water must flow from top to bottom through all the filter media before entering the central pipe and being output upwards. This extends the water flow path, ensures sufficient filtration, avoids dead zones and short-circuiting phenomena, and at the same time completely isolates the inlet and outlet channels in terms of structure.

[0019] In one possible implementation, the inlet port and outlet port are symmetrically arranged on both sides of the top of the connector, forming a T-shaped layout with the connector; the connector has an inlet flow channel cavity and an outlet flow channel cavity, and a partition wall is provided between the inlet flow channel cavity and the outlet flow channel cavity; the inlet flow channel cavity extends horizontally from the inlet port and then bends downward, communicating with the inlet cavity in the receiving cavity; the outlet flow channel cavity extends upward from the outlet cavity in the receiving cavity and then bends horizontally, communicating with the outlet port; both the inlet port and the outlet port have quick-connect fittings at their free ends.

[0020] Compared with existing technologies, the T-shaped symmetrical layout and the independent inlet and outlet water flow channel design with built-in partition walls enable the raw water and purified water to be physically isolated throughout the connection, avoiding cross-contamination. At the same time, the symmetrically configured quick-connect pipe joints facilitate quick connection of pipelines in the narrow space under the sink, simplifying installation.

[0021] Another technical solution of the present invention is to provide a control method for an under-sink water filter, comprising the following installation steps: S1. Initial positioning: Insert the stepped connector of the filter element into the receiving cavity of the connector, so that the screw-on clip enters the inlet of the spiral guide groove; S2. Twisting and pressurizing: Rotate the filter element to make the screw-on clip slide upward along the spiral mating surface, driving the stepped connector to generate axial displacement into the accommodating cavity; S3. Limiting and Connecting: Continue rotating the filter element until the screw-on clip abuts against the limiting block and is stopped. At this time, the radial seal enters a sealing state with an interference fit with the inner wall of the accommodating cavity. The water inlet port is connected to the water inlet channel, and the water outlet port is connected to the water outlet channel.

[0022] Compared with existing technologies, by connecting the three continuous actions of axial insertion, rotation, and limiting stop of the filter element connector, the axial compression and sealing of the filter element and the precise alignment and conduction of the inlet and outlet water channels are completed simultaneously in a short-stroke rotation operation. This allows locking, sealing, and channel switching to be achieved automatically without the need for separate force or additional alignment confirmation. This simplifies the operation process and eliminates the risk of structural damage or leakage caused by water being turned on before the seal is tightened or the channels are aligned. At the same time, the limiting stop provides a clear stop point to avoid over-tightening and ensure the repeatability and sealing reliability of the filter element each time it is installed. This is especially suitable for scenarios where filter elements can be quickly replaced with one hand in narrow spaces under the sink.

[0023] In one possible implementation, the following disassembly steps are also included: S4. Unlocking the circuit: Rotate the filter element in the opposite direction to the rotation direction in the installation step, so that the screw-on clip slides downward along the spiral mating surface, causing the stepped connector to move axially away from the receiving cavity, so that the radial seal is disengaged from the interference fit with the inner wall of the receiving cavity; S5. Disconnection and removal: When the screw-on clip slides to the inlet of the spiral guide groove, the filter element is removed vertically downwards.

[0024] Compared with existing technologies, the single continuous action of rotating the filter element in the opposite direction simultaneously releases the interference fit of the seal and cuts off the flow channel. When the screw-on clip returns to the inlet of the guide groove, it automatically returns to the unlocked state that can be axially disengaged. This allows the disassembly operation to be completed in one go without additional unlocking steps, completely avoiding damage to the seal or splashing of residual water caused by pressurized disassembly. It is both safe and fast.

[0025] In one possible implementation, in step S2, the rotation locking angle of the filter element is limited to between 60° and 120°.

[0026] Compared with existing technologies, the operation stroke required for filter cartridge installation is limited to a short turning angle of 60° to 120°. While ensuring that the spiral mating surface provides sufficient axial compression displacement to achieve a reliable seal, the operator can complete the locking with a single wrist turn without changing the grip posture, which is especially suitable for the operation constraints of narrow spaces under the sink. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of an under-sink water filter according to the present invention; Figure 2 This is a top view of an under-sink water filter according to the present invention; Figure 3 For the present invention Figure 2 A sectional view along the middle AA; Figure 4 For the present invention Figure 2 A sectional view along the middle edge BB; Figure 5 This is a schematic diagram of the filter element structure of an under-sink water filter according to the present invention; Figure 6 This is an exploded view of the connection of an under-sink water filter according to the present invention; Figure 7 This is a top view of the connector of an under-sink water filter according to the present invention.

[0028] Explanation of reference numerals in the attached figures: 1-Connector; 11-Accommodation cavity; 12-Helical guide groove; 121-Helical mating surface; 122-Limit stop; 13-Water inlet port; 14-Water outlet port; 2-Filter element; 21-Stepped connector; 22-Screw-on snap-fit ​​flap; 221-Inclined guide surface; 23-Inlet channel; 24-Outlet channel; 25-Radial platform; 251-First radial platform; 252-Second radial platform; 26-Radial seal; 261-First radial seal; 262-Second radial seal; 27-Central guide tube; 3- Anti-slip outer cover. Detailed Implementation

[0029] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0030] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0031] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0033] Example 1

[0034] See Figures 1 to 7 As shown in the figure, this application discloses a sink water filter, including a connector 1 and a filter element 2.

[0035] The connector 1 has a receiving cavity 11 at the bottom. A spiral guide groove 12 is provided on the inner peripheral wall of the receiving cavity 11. The lower groove wall of the spiral guide groove 12 forms a spiral mating surface 121. The connector 1 is provided with an inlet port 13 and an outlet port 14 leading to the receiving cavity 11. The filter element 2 has a stepped connector 21 at the top. The outer peripheral wall of the stepped connector 21 has a screw-fitting flap 22 that matches the spiral guide groove 12. The filter element 2 has an inlet channel 23 and an outlet channel 24. The stepped connector 21 has at least two radial platforms 25 from top to bottom. Each radial platform 25 is provided with a radial seal 26.

[0036] When the filter element 2 is rotated and locked, the screw-on latch 22 slides and rises along the spiral mating surface 121, causing the stepped connector 21 to move upward axially, so that the radial seal 26 forms an interference fit with the inner wall of the accommodating cavity 11; when the screw-on latch 22 reaches the locking end position of the spiral guide groove 12, the water inlet port 13 is connected to the water inlet channel 23, and the water outlet port 14 is connected to the water outlet channel 24.

[0037] By cooperating with the spiral guide groove 12 and the screw-on clip 22, the circumferential rotational torque is converted into axial clamping thrust, which greatly reduces the force threshold required to overcome sealing resistance. This allows users to easily complete quick disassembly and assembly with one hand in narrow spaces under the sink where visibility is obstructed. At the same time, combined with the multi-stage stepped radial sealing structure of the connector from top to bottom, when the clip slides along the spiral surface to the locking terminal position, it can achieve precise alignment of the inlet and outlet water passages and double-stage radial interference clamping. This physically isolates the raw water and pure water to prevent cross-leakage. The mechanical terminal limiting mechanism also ensures absolute consistency between physical locking and water passage conduction, eliminating the risk of detachment or leakage caused by improper blind operation installation from the structural root, and significantly improving the overall sealing reliability of the system and the user maintenance experience.

[0038] In this embodiment, a limiting block 122 is provided at the end of the spiral guide groove 12. When the screw-on latch 22 slides along the spiral mating surface 121 and abuts against the limiting block 122, it is stopped to limit the rotation stroke of the filter element 2. The limiting block 122 can provide a definite rotation stop point when the screw-on latch 22 arrives, preventing excessive twisting from damaging the seal, while ensuring that the filter element 2 is accurately stopped in the preset locking position, thereby reliably achieving accurate alignment and sealing with the inlet and outlet water channels 24.

[0039] The angle between the helical mating surface 121 and the horizontal plane is 5° to 15°; the top surface of the screw-on latch 22 is provided with an inclined guide surface 221 with the same slope as the helical mating surface 121. This angle range and the matching inclined guide surface 221 can smoothly and linearly convert the rotational operating force into axial clamping force, reducing operating resistance while ensuring that the radial seal 26 is uniformly compressed, avoiding seal failure or screwing jamming caused by local stress concentration.

[0040] In this embodiment, the stepped connector 21 includes a first radial platform 251 and a second radial platform 252 arranged from top to bottom. The water inlet channel 23 is located at an eccentric position of the stepped connector 21, and the water outlet channel 24 is located at the center position of the stepped connector 21. The radial seal 26 includes a first radial seal 261 disposed on the first radial platform 251 and a second radial seal 262 disposed on the second radial platform 252. The first radial seal 261 physically isolates the water inlet channel 23 and the water outlet channel 24 in the radial direction.

[0041] By combining the graded isolation of the double-layer radial seal 26 with the layout of the eccentric / central flow channel, independent inlet and outlet flow channels are constructed within the narrow space of the stepped joint 21. This not only prevents the medium from leaking outside the joint surface, but also structurally eliminates the risk of cross-contamination between inlet and outlet water inside the joint, significantly improving sealing reliability and isolation.

[0042] In this embodiment, the connector 1 is fitted with an anti-slip cover 3, and the outer surface of the anti-slip cover 3 is integrally formed with interwoven anti-slip textures. The cooperation between the anti-slip cover 3 and the integrally formed interwoven textures increases the frictional resistance between the palm and the cover when manually turning, making it easier to hold the connector 1 stably in a wet, slippery, and confined under-sink environment, thereby reliably applying reverse support force to complete the disassembly and assembly of the filter element 2.

[0043] The inlet port 13 and the outlet port 14 are located on the top outer side of the connector 1. They extend outward in opposite directions along the horizontal direction and are arranged with their central axes collinear, so that the horizontal pipeline structure formed by the inlet port 13 and the outlet port 14 is arranged in a T-shaped symmetrical structure that intersects the vertical central axis of the connector 1 perpendicularly.

[0044] The water inlet port 13 has an inlet channel inside. The inlet channel extends horizontally inward from the free end of the water inlet port 13 to the middle area of ​​the connector 1, and then bends downward at an angle to extend into the cavity 11. The water outlet port 14 has an outlet channel inside. The outlet channel extends from the inside of the cavity 11 to the middle area of ​​the connector 1, then bends downward at an angle and extends outward in a horizontal direction away from the inlet channel.

[0045] The bend transition sections of the inlet and outlet water channels are independently distributed back-to-back in the central converging area of ​​connector 1. They are physically isolated from each other by an integrally formed solid wall. Screws and fasteners for fastening the internal water channel structure and resisting internal water pressure impact are transversely inserted on the side wall of the central converging area.

[0046] Both the inlet port 13 and the outlet port 14 have quick-connect fittings coaxially embedded in their external free end holes. The inner cavities of the quick-connect fittings are connected to the horizontal extensions of the inlet and outlet channels, respectively, and are configured to form a quick-locking and fluid-sealing fit with the external water supply and outlet pipelines.

[0047] The T-shaped symmetrical layout and the independent inlet and outlet water channels with built-in partition walls ensure that the raw water and purified water are physically isolated throughout the connection head 1, avoiding cross-contamination. At the same time, the symmetrically configured quick-connect pipe fittings facilitate quick connection of pipes in the narrow space under the sink, simplifying installation.

[0048] In this embodiment, the filter element 2 has an overall axially symmetrical cylindrical structure, including a shell, a central guide tube 27 disposed inside the shell, a top cover assembly disposed on the top of the shell, and a support base disposed on the bottom of the shell. Its specific connection relationships and structural features are as follows: 1. Outer shell and inner cavity structure The outer shell is a hollow cylindrical shell with an internal accommodating space, closed at the bottom and open at the top.

[0049] The inner peripheral wall of the outer shell and the outer peripheral wall of the central guide tube 27 together form an annular filter media receiving cavity for filling the filter media (the specific cross-sectional texture of the filter media is not shown in the attached figure).

[0050] 2. Top cover assembly and quick-connect sealing structure The top open end of the housing is sealed with a top cover assembly, which extends upward to form a stepped connector 21 for rotational insertion into the receiving cavity 11 of the connector 1.

[0051] The outer wall of the stepped connector 21 has a multi-level stepped cylindrical structure, including a first radial platform 251 and a second radial platform 252 arranged from top to bottom. The water inlet channel 23 is located at the eccentric position of the second radial platform 252 of the stepped connector 21, and the water outlet channel 24 is located at the center of the first radial platform 251 of the stepped connector 21. The outer peripheral surface of the first radial platform 251 is provided with a first radial seal 261, and the outer peripheral surface of the second radial platform 252 is provided with a second radial seal 262. The first radial seal 261 physically isolates the water inlet channel 23 and the water outlet channel 24 in the radial direction.

[0052] The first radial seal 261 and the second radial seal 262 are arranged at intervals in the axial direction, so as to form a double radial seal after the connector 1 is inserted, thereby achieving physical isolation between the inlet channel and the outlet channel and preventing cross-flow between raw water and purified water.

[0053] The stepped connector 21 has an inlet channel inside that communicates with the eccentric position of the second radial platform 252.

[0054] 3. Central guide tube 27 structure The central guide tube 27 is vertically arranged along the central axis of the outer casing. The top end of the central guide tube 27 is tightly inserted into and fluidly connected to the central channel of the top cover assembly, and its bottom end extends axially downward to a position near the bottom of the outer casing. The interior of the central guide tube 27 forms an independent central water flow channel, which, together with the outer filter media receiving cavity, forms an "inward-inward-outward" filtration channel.

[0055] 4. Bottom support and limiting structure A support base is fixedly installed on the bottom inner surface of the outer casing. The cross-section of the support base is a stepped disc-shaped structure. The center of the support base protrudes upward to form a limiting sleeve. The lower end of the central guide pipe 27 is inserted into and abuts against the limiting sleeve, thereby radially limiting and axially supporting the lower end of the central guide pipe 27 to prevent it from shifting under water pressure. Fluid gaps or water passages are left around and inside the support base to maintain fluid communication between the filter media receiving cavity and the opening at the lower end of the central guide pipe 27, forming a complete water circulation reversal point.

[0056] Example 2

[0057] This embodiment relates to a control method for a drain filter, including the following installation steps: S1. Initial Positioning: Insert the stepped connector 21 of the filter element 2 into the receiving cavity 11 of the connector 1, so that the screw-on clip 22 enters the inlet of the spiral guide groove 12. The inlet of the receiving cavity 11 is provided with an asymmetrical guide part, which only allows the screw-on clip 22 to be inserted at a uniquely matched initial angle position, thereby achieving physical prevention of misinstallation.

[0058] S2. Tightening and pressurizing: Rotate the filter element 2 to make the screw-on clip 22 slide upward along the spiral mating surface 121, which drives the stepped connector 21 to generate axial displacement into the accommodating cavity 11.

[0059] S3. Limiting and Connecting: Continue rotating the filter element 2 until the screw-on clip 22 abuts against the limiting block 122 and is stopped. At this time, the radial seal 26 enters a sealing state with an interference fit with the inner wall of the accommodating cavity 11. Until the screw-on clip 22 abuts against the limiting block 122 and generates an elastic pre-compression of 0.5mm to 1.5mm, the water inlet port 13 is connected to the water inlet channel 23, and the water outlet port 14 is connected to the water outlet channel 24. After the radial seal 26 and the inner wall of the accommodating cavity 11 form a complete seal, the water inlet channel 23 and the water outlet channel 24 can finally achieve final connection through the internal structure.

[0060] S4. Unlock the circuit: Rotate the filter element 2 in the opposite direction of rotation in the installation steps, so that the screw-on clip 22 slides down along the spiral mating surface 121, causing the stepped joint 21 to move axially away from the receiving cavity 11, so that the radial seal 26 is disengaged from the interference fit with the inner wall of the receiving cavity 11.

[0061] S5. Disconnection and removal: When the screw-on clip 22 slides to the inlet of the spiral guide groove 12, remove the filter element 2 vertically downwards.

[0062] By connecting the three consecutive actions of axial insertion, rotation, and limiting stop of the filter element 2 connector, the axial compression and sealing of the filter element 2 and the precise alignment and conduction of the inlet and outlet water channels are completed simultaneously in a short-stroke rotation operation. This allows locking, sealing, and channel switching to be achieved automatically without the need for separate force or additional alignment confirmation. This simplifies the operation process and eliminates the risk of structural damage or leakage caused by water being turned on before the seal is tightened or the channels are aligned. At the same time, the limiting stop 122 provides a clear stop point to avoid over-tightening and ensure the repeatability and sealing reliability of the filter element 2 each time it is installed. This is especially suitable for scenarios where filter element 2 can be quickly replaced with one hand in narrow spaces under the sink.

[0063] By rotating the filter element 2 in a single, continuous motion, the interference fit of the seal is released and the flow channel is cut off simultaneously. When the screw-on clip 22 retracts to the inlet of the guide groove, it automatically returns to the unlocked state that can be axially disengaged. This allows the disassembly operation to be completed in one go without any additional unlocking steps, completely avoiding damage to the seals or splashing of residual water caused by pressurized disassembly. It is both safe and quick.

[0064] In step S2, the rotation locking angle of filter element 2 is limited to between 60° and 120°.

[0065] The required operating stroke for installing the filter element 2 is limited to a short turning angle of 60° to 120°. While ensuring that the spiral mating surface 121 provides sufficient axial compression displacement to achieve a reliable seal, the operator can complete the locking with a single wrist turn without changing the grip posture, which is especially suitable for the operation limitations of narrow spaces under the sink.

[0066] In the description of the embodiments of this application, it should be noted that the terms "inner" and "outer" and other terms indicating direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0067] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A drain filter for under-sink water, characterized in that, Includes connector (1) and filter element (2); The connector (1) has a receiving cavity (11) at the bottom. A spiral guide groove (12) is provided on the inner peripheral wall of the receiving cavity (11). The lower groove wall of the spiral guide groove (12) forms a spiral mating surface (121). The connector (1) is provided with an inlet port (13) and an outlet port (14) leading to the receiving cavity (11). The filter element (2) is provided with a stepped connector (21) at the top. The outer peripheral wall of the stepped connector (21) is provided with a screw-fitting flap (22) that is compatible with the spiral guide groove (12). The filter element (2) is provided with an inlet channel (23) and an outlet channel (24). The stepped connector (21) is provided with at least two radial platforms (25) from top to bottom. Each radial platform (25) is provided with a radial seal (26). When the filter element (2) is rotated and locked, the screw-on latch (22) slides and rises along the spiral mating surface (121), causing the stepped connector (21) to move upward axially, so that the radial seal (26) and the inner wall of the accommodating cavity (11) form an interference fit; when the screw-on latch (22) reaches the locking end position of the spiral guide groove (12), the water inlet port (13) is connected to the water inlet channel (23), and the water outlet port (14) is connected to the water outlet channel (24).

2. The under-sink water filter according to claim 1, characterized in that, The end of the spiral guide groove (12) is provided with a limiting block (122). When the screw-on clip (22) slides along the spiral mating surface (121) and comes into contact with the limiting block (122), it is stopped to limit the rotation stroke of the filter element (2).

3. The under-sink water filter according to claim 1, characterized in that, The angle between the spiral mating surface (121) and the horizontal plane is 5° to 15°; the top surface of the screw-on card (22) is provided with an inclined guide surface (221) with the same slope as the spiral mating surface (121).

4. The under-sink water filter according to claim 1, characterized in that, The stepped connector (21) includes a first radial platform (251) and a second radial platform (252) arranged from top to bottom. The water inlet channel (23) is located at an eccentric position of the stepped connector (21), and the water outlet channel (24) is located at the center position of the stepped connector (21). The radial seal (26) includes a first radial seal (261) disposed on a first radial platform (251) and a second radial seal (262) disposed on a second radial platform (252), wherein the first radial seal (261) physically isolates the water inlet channel (23) from the water outlet channel (24) in the radial direction.

5. The under-sink water filter according to claim 1, characterized in that, The connector (1) is covered with an anti-slip cover (3), and the outer surface of the anti-slip cover (3) is integrally formed with interwoven anti-slip patterns.

6. The under-sink water filter according to claim 1, characterized in that, The filter element (2) has a central guide tube (27) axially arranged inside. The upper end of the central guide tube (27) is sealed and connected to the water outlet channel (24), and the lower end penetrates the filter medium area of ​​the filter element (2) and extends to the bottom of the inner cavity of the filter element (2).

7. The under-sink water filter according to claim 1, characterized in that, The inlet port (13) and outlet port (14) are symmetrically arranged on the top two sides of the connector (1), forming a T-shaped layout with the connector (1); The connector (1) is provided with an inlet flow channel cavity and an outlet flow channel cavity, and a partition wall is provided between the inlet flow channel cavity and the outlet flow channel cavity; the inlet flow channel cavity extends horizontally from the inlet port (13) and then bends downward to communicate with the inlet cavity in the accommodating cavity (11); the outlet flow channel cavity extends upward from the outlet cavity in the accommodating cavity (11) and then bends horizontally to communicate with the outlet port (14); The free ends of the water inlet port (13) and the water outlet port (14) are both equipped with quick-connect pipe connectors.

8. A control method for a sink drain filter according to any one of claims 2 to 7, characterized in that, The installation process includes the following steps: S1. Initial positioning: Insert the stepped connector (21) of the filter element (2) into the receiving cavity (11) of the connector (1) so that the screw-on clip (22) enters the inlet of the spiral guide groove (12); S2. Twisting and pressurizing: Rotate the filter element (2) to make the screw-on clip (22) slide and rise along the spiral mating surface (121), causing the stepped connector (21) to move axially into the accommodating cavity (11); S3. Limiting and Connecting: Continue rotating the filter element (2) until the screw-on latch (22) abuts against the limiting block (122) and is stopped. At this time, the radial seal (26) enters a sealing state with interference fit with the inner wall of the accommodating cavity (11). The water inlet port (13) is connected to the water inlet channel (23), and the water outlet port (14) is connected to the water outlet channel (24).

9. The control method for the under-sink water filter according to claim 8, characterized in that, The following disassembly steps are also included: S4. Unlock the circuit: Rotate the filter element (2) in the opposite direction to the rotation direction in the installation step, so that the screw-on clip (22) slides down along the spiral mating surface (121), causing the stepped connector (21) to generate axial displacement in the direction away from the accommodating cavity (11), so that the radial seal (26) is disengaged from the interference fit with the inner wall of the accommodating cavity (11); S5. Disconnection and removal: When the screw-on clip (22) slides to the entrance of the spiral guide groove (12), the filter element (2) is removed vertically downward.

10. The control method for the under-sink water filter according to claim 8, characterized in that, In step S2, the rotation locking angle of the filter element (2) is limited to between 60° and 120°.

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