Filter Cartridge

Abstract

A filter cartridge for use in a filtration device for filtering liquids, the filter cartridge comprising a cap (8) displaceably mounted on a housing (2) between an actuation position, the cap (8) defining an actuation compartment (10) fluidly connected with an actuation port (19) of the housing (2), and a use position in which the volume of the actuation compartment (10) is reduced. The cap (8) comprises an actuation opening (11) and a use opening (20). In the actuation position, the actuation compartment (10) inside the cap (8) can be filled with liquid through the actuation opening (11) of the cap (8). Displacement of the cap (8) closes the actuation opening of the cap and reduces the volume of the actuation compartment to force at least a portion of the fluid from the actuation compartment through the actuation port into the housing, then through the filter material, until the cap in the use position contacts the housing, causing the use opening of the cap to overlap the inlet port of the housing, allowing fluid to pass through the inlet port and enter the housing.

Description

[Technical field]

[0001] The present invention relates to a filter cartridge for use in a filtration device for filtering liquids, the filter cartridge comprising a housing and a filter media disposed within the housing, the housing having an inlet port and an outlet port such that a fluid flow of the liquid may enter the housing through said inlet port and then pass through the filter media within the housing before exiting the housing through the outlet port. [Background technology]

[0002] Many filter devices for liquids comprise at least one filter cartridge through which the liquid to be filtered flows and can be filtered in the process. Thus, a filter material is disposed in the housing of the filter cartridge. The housing has an inlet port and an outlet port, and the filter material is disposed in the housing such that the liquid entering the housing through the inlet port contacts or passes through the filter material before exiting the housing through the outlet port. Some filter cartridges consist of one or more filter media disposed in the housing, allowing different filtering processes to be performed during one pass of the liquid. Filter cartridges used for potable water filtration usually comprise one or more filter media, such as activated carbon or ion exchange materials, which are used for the removal of unwanted water impurities, as well as for the removal of impurities that affect the taste, odor, and hardness of the water.

[0003] The filter media within the filter cartridge are depleted during use of the filter cartridge to filter increasing volumes of liquid. After filtering a large volume of liquid, the filter cartridge is depleted and must be removed and replaced with a new filter cartridge. Therefore, filter cartridges are typically removably mounted within the filter system.

[0004] Many filter cartridges include a filter medium that requires aeration or washing with water or another liquid before the filter cartridge can be used fully efficiently. In particular, hollow fiber filtration materials require complete aeration to remove all residual air between or within the hollow fibers. For practical reasons, it is known to flush the housing with some liquid (usually water) before starting actual use of the filter cartridge. If the amount of liquid used to aerate the filter medium is large enough, most or all of the air will be flushed out, improving filter efficiency during subsequent use to filter liquid flowing through the housing.

[0005] When the flow of liquid through the filter device is caused by gravity, it takes a certain amount of time for the preset amount of liquid to flow through the housing. This duration usually does not affect the daily use of such a filtering device, but for a long period of time it is inconvenient to prepare the filter cartridge at the beginning of its use and at the beginning of its service life. Usually, before starting the actual use of the filter device to filter liquid, the user inserts the filter cartridge into the filter device and waits for the preset amount of liquid to flow through the filter cartridge to remove the amount of liquid used for the first aeration of the filter cartridge.

[0006] Patent Document 1 discloses a filter apparatus with a filter cartridge and a pump, whereby the pump can be manually operated to force the liquid to be filtered through the filter cartridge. Patent Document 2 discloses a portable filter apparatus with a filter cartridge and a pump for manually operating the filter apparatus in an outdoor environment. However, such a filter device requires manual operation during the filtering process and cannot utilize gravity, which is not necessary for most applications except for flushing the filter cartridge at the first operation for a short period of time. Typically, a user does not want to have to manually operate the pump of the filter apparatus to filter a certain amount of liquid. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2010 / 091467 [Patent Document 2] U.S. Patent No. 8,343,347 Summary of the Invention [Problem to be solved by the invention]

[0008] There is therefore a need for a filter cartridge that allows for simple and quick venting prior to actual use of the filter cartridge for filtering liquids, but does not require manual operation of the filter device for each filtering process during the use and service life of the filter cartridge. [Means for solving the problem]

[0009] The present invention relates to a filter cartridge as defined in claim 1. The filter cartridge comprises a cap movably mounted on the housing between an actuation position and a use position in which the volume of the actuation compartment is reduced, in which the cap forms an actuation compartment fluidly connected to an actuation port of the housing. The cap comprises an actuation opening and a use opening, the cap being displaceable from the actuation position to the use position in which the actuation compartment inside the cap can be filled with liquid through the actuation opening of the cap. The displacement of the cap closes the actuation opening of the cap and reduces the volume of the actuation compartment to force at least a portion of the fluid from the actuation compartment through the actuation port and into the housing until the cap in the use position contacts the housing, then through the filter material so that the use opening of the cap overlaps with the inlet port of the housing, allowing the fluid to pass through the inlet port and enter the housing.

[0010] To vent the filter cartridge before using it to filter liquid, the cap can be moved or placed in an operating position, where it forms an operating compartment bounded by the cap and a part of the housing facing the cap. The operating compartment can be filled with liquid through an operating opening in the cap. The cap can then be displaced into a use position, in which the volume of the operating compartment is smaller than when the cap is in the operating position, so that liquid can be forced out of the operating compartment by any opening in the operating compartment available for liquid to be discharged from the operating compartment. By closing the operating opening in the cap, the liquid must leave the operating compartment through the housing before being discharged through the operating port into the housing and then through the outlet port of the housing. This results in a quick aeration of the filter media arranged inside the housing. This process of venting the filter cartridge can be carried out repeatedly as necessary or if considered advantageous to improve the filter efficiency during subsequent use of the filter device. To repeat the operating process, the cap can be displaced into the operating position and the operating compartment formed by the cap can be filled with liquid again. The cap can then be displaced to the use position, thereby reducing the volume of the actuation compartment and allowing excess liquid to flow out of the smaller actuation compartment and through the actuation port into the housing.

[0011] After completion of such an actuation procedure resulting in sufficient aeration of the filter cartridge, the cap remains in the use position, where the use opening of the cap overlaps with the inlet port of the housing, allowing the filter cartridge to be used indefinitely during subsequent use to filter liquids exiting the inlet port, the housing, and the outlet port. No further displacement of the cap is required during the useful life of the filter cartridge. There is no need to remove the cap or continually operate or replace the cap to perform the filtering process.

[0012] Furthermore, the cap remains attached to the housing of the filter cartridge. The cap is therefore available to carry out the actuation process again for the entire service life of the filter cartridge. There is no risk of losing or misplacing the cap, which could accelerate the aeration process of the filter cartridge.

[0013] In one embodiment, the filter cartridge includes a positive guide for guiding displacement of the cap relative to the housing. The positive (i.e., form-close) guide defines a motion sequence for displacement of the cap between the actuation position and the use position and prevents the user from displacing the cap in such a way that the venting of the filter cartridge is not accelerated. The positive guide can define a direction of movement during displacement to facilitate manual manipulation of the cap during the venting process. Additionally, the positive guide can also be designed to prevent unintentional removal of the cap from the housing of the filter cartridge.

[0014] In an embodiment, the filter cartridge includes a positive retention that holds the cap in the use position. The positive retention comprises a portion that cooperates with the cap to provide a form-locked joint. The positive retention can be provided by a latching tongue that engages a recess. The positive retention can also be provided by a spring-loaded latching element, such as a pin or bolt, that engages a corresponding recess or hole. Such positive retention prevents the cap from unintentionally shifting during use of the filter cartridge, which could interfere with or reduce the effectiveness of the filter cartridge.

[0015] In an embodiment, the housing has a side surface and a housing end face facing the cap, the cap has a side face closed on one side and adapted to surround the side face of the housing, the cap surrounds the housing end face and a part of the side face of the housing. The cross section of the housing perpendicular to the side face may be circular or elliptical. The cross section may also be rectangular or polygonal in shape. The cap can be easily displaced in an axial direction parallel to the side face and perpendicular to the cross section perpendicular to the side face. The cap can be moved to an activation position where the closed side of the cap is furthest away from the housing end face of the housing, or to a use position where the closed side of the cap is next to or in contact with the housing end face of the housing. The side face of the cap and the sealed housing provide a positive guide that prevents lateral movement of the cap relative to the housing.

[0016] In an embodiment, the side and closed side of the cap and the housing end face of the housing enclose and enclose an actuation compartment defined by the cap in the actuation position. If the housing end face of the housing and the closed side of the cap are similarly shaped, the cap can be moved to the use position with the closed side of the cap tightly pressed against the end face of the housing, thereby reducing the volume of the actuation compartment to zero in the use position.

[0017] In an embodiment, the housing has a cylindrical shape and the cap has a hollow cylindrical shape, whereby the inner diameter of the side of the cap is equal to or greater than the outer diameter of the side surface of the housing. Such shapes of the cap and housing allow rotational movement of the cap relative to the housing. When the inner and outer diameters of the respective sides match, the side surface provides a positive guide that allows displacement of the cap in the axial and circumferential directions parallel to the side. The circumferential rotational displacement of the cap can be used to easily align the cap in its use position so that the use opening of the cap overlaps with the inlet port of the housing.

[0018] In one embodiment, the positive guide comprises a groove in either the housing or the cap side. A feature or cam that protrudes beyond the other side can engage with the groove such that the course of the groove defines and limits the displacement of the cap relative to the housing. Such a positive guide, formed by interengaging grooves and corresponding formations, provides reliable guidance during displacement and can also withstand greater forces applied to the cap during actuation.

[0019] In one embodiment, the formation contained within the housing is arranged to close the actuation opening upon a first, e.g., rotational, displacement formation that forms part of the displacement of the cap from the actuation position to the use position, and further displacement after the first displacement is completed and the actuation opening is closed by the formation includes an axial displacement that reduces the size of the actuation compartment.

[0020] The structure may be provided, for example, in an extension of a side surface of the housing or may be provided in the form of an extension, the first displacement causing the structure to move and then the side surface to move into overlap with the actuation opening.

[0021] In a particular embodiment, the groove comprises an actuation section forcing a rotational displacement of the cap near the actuation position and a vent section forcing an axial displacement of the cap towards the use position. The rotational displacement near the actuation position provides a closure of the actuation opening located in the side of the cap and displaced onto a tongue-like cover formed by the formation of the housing. During the rotational displacement of the cap, the volume of the actuation compartment is not reduced and the liquid filled in the actuation compartment is not pushed out of the actuation compartment, which would result in an undesirable leakage of liquid through the not yet closed actuation opening. After the rotational displacement is completed and the actuation opening is closed by the tongue-like cover provided by the housing, further displacement of the cap includes an axial displacement defined by the vent section of the groove and reducing the size of the actuation compartment, thereby forcing a corresponding amount of liquid to flow out of the actuation compartment through the inlet port and through the filter media in the housing. At the end of the displacement, the groove may form a locking section, limiting the displacement of the cap to only the rotational displacement. Thus, pressure exerted by fluid flowing through the filter cartridge creates an axial force tending to push the cap away from the housing, which is blocked by the locking section, which only allows rotational movement of the cap when in the use position.

[0022] In one embodiment, the groove in the side surface comprises a helical arc section that provides for coaxial and rotational displacement of the cap relative to the housing. The above-mentioned use section may be helical. Thus, a screwing motion applied to the cap and housing results in the axial displacement that is required to vent the filter media within the housing. Such a screwing motion is easy to perform and combines both axial and rotational displacements to help smooth the transition from full rotational displacement at the beginning and end of full cap displacement to the primarily axial displacement required to vent the filter media.

[0023] In yet another embodiment of the invention, the actuation opening is located in the side of the cap next to the closed side of the cap, the actuation port of the housing is located in the end face of the housing facing the cap, and the outlet port of the housing is located in the end face of the housing opposite the end face of the housing facing the cap. The actuation port of the housing can be the same as the inlet port. However, depending on the design of the housing and cap, it is possible to provide a different actuation port that is open during the actuation process, while the inlet port remains covered by the cap until the cap is displaced to the use position. The location of the actuation port opposite the outlet port allows a direct flow path through the housing during the actuation process and supports complete and rapid venting of the filter cartridge.

[0024] In an embodiment of the present invention, the use opening is located in the side of the cap opposite the closed side of the cap, and the inlet port of the housing is located in the side of the housing such that the use opening of the cap placed in the use position overlaps with the inlet port of the housing and liquid passes into the housing through the inlet port overlapping with the use opening. After the activation process, the cap is placed in the end position and remains in the end position during the service life of the filter cartridge. In the end position, the use opening formed in the cap overlaps with the inlet port of the housing, which allows liquid to flow through the inlet port without adverse effects or restrictions due to the cap overlapping a large part of the housing. According to the requirements of the filter cartridge and the design of the housing, the housing may be provided with several inlet ports, and the cap may be provided with several use openings that overlap to provide a large cross-sectional area through which liquid can enter the housing during normal use of the filter cartridge.

[0025] In one embodiment, the use opening is closed by a side of the housing between the operative position and the use position.

[0026] To facilitate handling and displacement of the cap during the actuation process, the cap optionally includes a handle for manual displacement of the cap relative to the housing. The handle may be a single knob protruding from the cap. The handle may be a gripping element or a protruding loop that facilitates gripping and moving the cap.

[0027] The present invention will be more fully understood, and further features will become apparent, upon reference to the following detailed description and the accompanying drawings, in which: The drawings are merely representative and are not intended to limit the scope of the claims. Indeed, those skilled in the art will recognize, upon reading the following specification and viewing the drawings, that various modifications and variations can be made thereto without departing from the innovative concept of the present invention. Similar parts depicted in the drawings are referenced with the same numerals. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 shows a schematic diagram of a filter cartridge with a cap movably attached to the filter cartridge housing and providing for an actuation compartment, the cap being placed in an actuation position in which the filter cartridge is ready for actuation. [Diagram 2] 2 shows a cross-sectional view of the filter cartridge shown in FIG. 1 taken along line II-II in FIG. [Diagram 3] 3 illustrates a perspective view of the filter cartridge shown in FIGS. 1 and 2 with the cap disposed in an operative position. [Figure 4] FIG. 4 shows a schematic diagram of the filter cartridge shown in FIGS. 1 to 3 (with the cap placed in the use position of the filter cartridge). [Diagram 5] 5 shows a cross-sectional view of the filter cartridge shown in FIG. 4 taken along line VV in FIG. [Figure 6] FIG. 6 shows a perspective view of the filter cartridge shown in FIGS. 4 and 5 with the cap in the use position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] 1-6 illustrate an exemplary embodiment of a filter cartridge 2 comprising a housing 2 and a filter medium 3 disposed within the housing 2. The filter medium 3 comprises a hollow fiber membrane having a plurality of hollow fibers that must be vented prior to first use of the filter cartridge 1 to remove residual air from the hollow fiber membrane which would reduce the efficiency of the filter cartridge 1 during use.

[0030] The housing 2 of the filter cartridge 1 is a hollow cylinder having sides 4. The housing 2 has two inlet ports 5 located in the sides 4 on opposite portions of the housing 2. An outlet port 6 is located at a housing end face 7. The filter media 3 is disposed within the housing 2 in a manner that provides a liquid flow path such that liquid enters the housing 2 through the inlet ports 5, passes through the filter media 3, and exits the housing 2 through the outlet port 6.

[0031] The filter cartridge 1 also comprises a cap 2 movably mounted on the housing 2. The cap 8 is hollow and cylindrical and covers a housing end face 9 facing the cap 8. However, the cap 8 can be moved between an actuated position, shown in Figs. 1 to 3, and a use position, shown in Figs. 4 to 6. The cap 8 in the actuated position forms an actuating compartment 10, which is bounded by the cap 8 and the housing end face 9 of the housing 2 facing the cap 8. The cap 8 comprises an actuating opening 11, which is located in a side surface 12 of the cap 8 and provides access to the actuating compartment 10 in the cap 8. The volume of the actuating compartment 10 changes with the movement of the cap 8 relative to the housing 2, in particular with respect to the housing end face 9.

[0032] The housing 2 comprises two grooves 13 in the side 4 extending along the side 4 on opposite sides of the side 4. The grooves 13 and some other parts of the filter cartridge 1 covered by the cap 8 are shown in dashed lines. Each of the grooves 13 is formed on the inside 15 of the cap 8 and forms a positive guide for the inwardly directed projections 14. The course of each groove 13 is identical but opposite to each other. Each groove 13 comprises an actuating portion 15 which forces an independent rotational movement of the cap 8 near the operating position of the cap 8. Each of the grooves 13 then comprises a vent portion 16 having a helical course which forces an axial movement of the cap 8 in the direction towards the housing 2, resulting in a reduction in the volume of the operating compartment 10. Opposite the actuating portion 15, each groove 13 comprises a locking portion 17 which again forces an independent rotational movement of the cap 8 near the use position of the cap 8. Thus, in the use and operative positions of the cap 8, any axial force applied to the cap 8 cannot cause displacement of the cap 8 due to the sole rotational movement permitted by the course of the grooves 13 in the use and operative positions. No additional means are required to lock the cap 8 in either the operative or use positions for proper operation and use of the filter cartridge 1.

[0033] Preferably, before the first use of the filter cartridge 1, the cap 8 is manually moved into the working position. The volume of the working compartment 10 formed by the cap 8 is then filled with liquid through the working opening 11. The cap 8 is then manually displaced towards the use position. Due to the course of the grooves 13, the cap 8 starts with a rotational displacement. The working opening 11 is formed by the formation of the housing 2, which protrudes axially from the housing end face 9, and slides in rotation on a tongue-shaped cover 18 having an outer surface flush with the side face 4 of the housing 2. The working opening 11 is thereby closed by the tongue-shaped cover 18 at the beginning of the displacement of the cap 8 forced by the course of the grooves 13.

[0034] After closing of the actuation opening 11, the cap 8 is displaced along the helical course of the vent 16 of the groove 13, resulting in a decrease in the volume of the actuation compartment 10, forcing the liquid out of the actuation compartment 10 and through the cap 8 and the actuation port 19 formed therein and located in the housing end face 9 facing the actuation compartment 10. The manual displacement of the cap 8 forces the liquid to flow through the housing 2 and the filter media 3 therein, thereby venting the filter cartridge 1 by removing any residual air that may have been trapped in the filter media 3. This process can be carried out repeatedly as necessary or as deemed appropriate.

[0035] The cap 8 is then placed in a use position and the fully vented filter cartridge 1 is inserted into the filter device for filtering liquid with high efficiency. To allow easy entry of liquid into the housing 2, the cap 8 is provided with two use openings 20 located in a side 12 of the cap 8 such that each of the two use openings 20 overlaps a corresponding inlet port 5 of the housing 2 when the cap 8 is placed in the use position. Thus, liquid flowing through the filter cartridge 1 enters the housing 2 through the inlet openings 20 and the corresponding input port 5, flows through the filtration media 3 and exits the filter cartridge 1 through the outlet port 6 located opposite the cap 8.

[0036] To facilitate the manually performed venting process of the filter cartridge 1 , the cap 8 includes a handle 21 formed on an outer surface of the cap 8 and projecting away from the housing 2 .

Claims

1. 1. A filter cartridge for use in a filtration device for filtering a liquid, comprising: The filter cartridge (1) comprises a housing (2) and a filter medium (3) disposed within the housing (2); The housing (2) includes an inlet port (5) and an outlet port (6) such that a fluid flow of a liquid may enter said housing (2) through the inlet port (5) and then pass through a filter medium (3) within said housing before the fluid flow exits said housing (2) through the outlet port (6). In the filter cartridge, The filter cartridge (1) comprises a cap (8) displaceably mounted on the housing (2) between operative positions; The cap (8) defines an actuation compartment (10) in fluid communication with the actuation port (19) of the housing (2) and a use position in which the volume of the actuation compartment (10) is reduced; The cap (8) has an actuation opening (11) and a use opening (20); the cap (8) is movable from an actuated position to a use position such that in the actuated position an actuating compartment (10) inside the cap (8) can be filled with liquid through an actuating opening (11) in the cap (8); The displacement of the cap (8) closes the actuation opening (11) of the cap (8) and reduces the volume of the actuation compartment (10) until the cap in the use position contacts the housing (2), forcing at least a portion of the fluid from the actuation compartment (10) through the actuation port (19) into the housing (2), then through the filter medium (3), causing the actuation opening (19) of the cap to overlap the inlet port (5) of the housing (2), allowing the fluid to pass through the inlet port (5) and enter the housing (2). A filter cartridge comprising:

2. The filter cartridge (1) is provided with a positive guide to guide the displacement of the cap (8) relative to the housing.

2. The filter cartridge of claim 1.

3. The filter cartridge (1) is provided with a positive retention that holds the cap (8) in the use position.

3. The filter cartridge according to claim 2.

4. The housing (2) has a side surface (4) and a housing end surface (9) facing the cap (8), The cap (8) is closed on one side and has a side (12) adapted to surround the side (4) of the housing (2); The cap (8) surrounds a portion of the side surface (4) of the housing (2) and the housing end surface (9).

4. The filter cartridge according to claim 1, wherein the filter cartridge is a filter cartridge having a first opening and a second opening.

5. The housing end face (9) of the housing (2) as well as the side face (12) of the cap (8) enclose and surround an actuation compartment (10) formed by the cap (8) in the actuation position; 5. The filter cartridge according to claim 4.

6. a formation (18) contained within the housing (12) arranged to close the actuation opening (11) upon a first, e.g. rotational, displacement formation forming part of the displacement of the cap (8) from the actuation position to the use position, further displacement after the first displacement is completed and the actuation opening (11) is closed by the formation includes an axial displacement which reduces the size of the actuation compartment (10); 6. The filter cartridge according to claim 4 or 5.

7. The housing (2) is cylindrical and the cap (8) is hollow cylindrical; The inner diameter of the side surface (12) of the cap (8) is equal to or greater than the outer diameter of the side surface (4) of the housing (2); 7. The filter cartridge according to claim 4, wherein the filter cartridge is a filter cartridge having a diameter of 100 mm or less.

8. The positive guide comprises a groove (13) on either side (4, 12) of the housing (2) or the cap (8); 8. A filter cartridge according to claims 2 and 7.

9. The groove (13) comprises an actuation section (15) arranged to urge rotational displacement of the cap (8) near an actuation position and a vent section (16) arranged to urge axial displacement of the cap (8) towards a use position.

9. The filter cartridge of claim 8.

10. the grooves (13) in the sides (4, 12) have a helical arcuate cross section which simultaneously provides axial and rotational displacement of the cap (8) relative to the housing (2); 10. The filter cartridge of claim 9.

11. The actuation opening (11) is located on a side (12) of the cap (8) next to the closed side of the cap (8); The operating port (19) of the housing (2) is located in the housing end face (9) facing the cap (8); The outlet port (6) of the housing (2) is located in an end face of the housing opposite the end face (9) facing the cap (8); The filter cartridge according to any one of claims 4 to 10.

12. The use opening (20) is located in a side (12) of the cap (8) opposite the closed side of the cap (8); the inlet port (5) of the housing (2) is located in a side of the housing (2) such that a use opening (20) of the cap (8) disposed in a use position overlaps with the inlet port (5) of the housing (2) and liquid passes into the housing (2) through the inlet port (5) overlapping with the use opening (20); The filter cartridge according to any one of claims 4 to 11.

13. The use opening (20) is closed by a side surface (4) of the housing (2) between the operating position and the use position. The filter cartridge according to any one of claims 4 to 12.

14. The cap (8) is provided with a handle (21) for manually displacing the cap (8) relative to the housing (2); The filter cartridge according to any one of claims 1 to 13.

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