Cartridge for water purifier and water purifier

Abstract

To provide a safe water purifier cartridge having no risk that a granular material such as active carbon may scatter around or water may spout out even when a water purifier cartridge comes to break up because the cartridge has been used far beyond an assumed service period due to user's negligence of replacement.SOLUTION: A water purifier cartridge includes a bottomed cylindrical cartridge case, a filter material housed inside the cartridge case, and a lid fixed around an opening of the cartridge case, where the lid includes a disk-shaped ceiling part and a cylindrical part hanging from a peripheral part of the ceiling part, and a thin part having thin thickness is formed on a surface of the ceiling part, the surface facing an inside of the cartridge case.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a replaceable water purifier cartridge attached to a main body switch of a water purifier that filters tap water in a household kitchen.

Background Art

[0002] Water purifiers that purify tap water at home are widely used. Various filter materials such as activated carbon that removes free residual chlorine, mold odor, and trihalomethane in tap water, ion exchangers that remove lead, and hollow fiber membranes that remove turbidity are housed in the water purifier cartridges of water purifiers. Many water purifier cartridges have a case and a lid, and their internal spaces are filled with various filter materials.

[0003] Since the amount of filtered water that these filter materials can handle is limited, it is common to continue using the water purifier while periodically replacing the water purifier cartridge. Each time the faucet of the water purifier is opened and closed, water pressure is applied. As the clogging of the filter material progresses, the water pressure increases. However, since it is replaced with a new water purifier cartridge when the filtering function deteriorates, it does not lead to damage. The pressure resistance of the water purifier cartridge is designed with a safety factor based on the maximum operating water pressure and the service life.

[0004] However, despite such design considerations, if the user neglects to replace the water purifier cartridge and uses it significantly beyond the assumed service life, the clogging of the filter material progresses more than expected and a water pressure exceeding the maximum operating water pressure is applied, or the number of times the water pressure is applied significantly exceeds the assumption, the water purifier cartridge may be damaged. When the case of the water purifier cartridge is damaged, there is a problem that granular filter materials such as activated carbon scatter and the kitchen floor is soiled.

[0005] In view of this problem, Patent Document 1 proposes a water purifier cartridge in which the pressure resistance of the lid is made smaller than the pressure resistance of the case. Even when a large water pressure is applied inside the water purifier cartridge, before the case is damaged, a small crack will appear in the lid with a weak pressure resistance, and water will leak out from there. Therefore, even if the lid is damaged, the case will not be damaged, so the granular filter medium will not scatter around.

[0006] Further, Patent Document 2 proposes a storage container having a container body with a crack generation part and a lid member covering one end of the container body. Since the crack generation part is provided at one end of the container body, even if a crack occurs in the crack generation part when a large water pressure is applied to the container body, the lid member will not have a crack. Furthermore, the water leaking from the crack can move between the container body and the lid member and reach the outside, releasing the internal pressure.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, in the technology of Patent Document 1, at the moment when the lid that has withstood a large water pressure is damaged, the crack generated in the lid may expand all at once. If the crack in the lid spreads too much, there is a concern that water will spurt out from the crack in the lid even if the filter medium does not scatter around, and as a result, the kitchen floor will be flooded.

[0009] Also, in the technology of Patent Document 2, since the range of the male screw part, which is the crack generation part, is wide, a crack may accidentally enter the root of the male screw. And if the container body, which has withstood a large water pressure, breaks all at once starting from the crack generation part at the root of the male screw, it cannot be denied that the contained filtering material may scatter around or water may spurt out.

[0010] In view of the above problems, the present invention provides a safe water purifier cartridge in which, even if the user neglects to replace the water purifier cartridge and uses it significantly beyond the assumed usage period until the water purifier cartridge is damaged, granular filtering materials such as activated carbon do not scatter around or water does not spurt out.

Means for Solving the Problems

[0011] The water purifier cartridge of the present invention for solving the above problems includes a bottomed cylindrical cartridge case, a filtering material housed inside the cartridge case, and a lid fixed near the opening of the cartridge case. The lid has a disk-shaped top surface portion and a cylindrical portion hanging down from the peripheral edge portion of the top surface portion. A thin portion with a thin wall thickness is formed on the surface of the top surface portion facing the inside of the cartridge case.

[0012] The water purifier cartridge of the present invention is preferably in any of the following aspects. · With the inner diameter of the cylindrical portion being D and the center of the top surface portion being the center of the circle, the thin portion is outside the circle with a diameter of 0.05D and crosses the range from the circle with a diameter of 0.07D to the circle with a diameter of 0.8D. · The thin portion spreads radially with the center of the top surface portion as the center point. · With the thickness of the top surface portion other than the thin portion being t, the thickness of the thinnest part of the thin portion is 0.3t or more and 0.7t or less. · It has an inner lid disposed between the lid and the filtering material and partitioning the lid and the filtering material. The inner lid has a watertight engagement portion that is watertightly engaged with the cartridge case, and a flange portion that protrudes radially upward from the upper portion of the watertight engagement portion. With the height of the cylindrical portion being L1 and the length from the upper surface of the inner lid to the upper surface of the flange portion being L2, L1 > L2 is satisfied.

[0013] The water purifier of the present invention is equipped with the cartridge for water purifier of the present invention.

Effect of the Invention

[0014] According to the cartridge for water purifier of the present invention, even if the user neglects to replace the cartridge for water purifier and uses it significantly beyond the assumed usage period, and even if the water purifier cartridge reaches the point of destruction, minute cracks will occur in the thin-walled portion provided on the top surface of the lid body, and a small amount of water will leak to release the water pressure. Therefore, water will not spurt out and the filter material will not scatter around. The user can notice from the small amount of water leakage from the cracked thin-walled portion that they have been using it significantly beyond the usage period.

[0015] According to the cartridge for water purifier in a preferred embodiment of the present invention, with the inner diameter of the cylindrical portion of the lid body being D and the center of the top surface being the center of the circle, the thin-walled portion is outside the circle with a diameter of 0.05D and crosses the range from the circle with a diameter of 0.07D to the circle with a diameter of 0.8D. Therefore, even if the lid body is damaged, there is a low possibility that the crack will spread to the peripheral edge of the top surface of the lid body all at once.

[0016] Also, according to the cartridge for water purifier in another preferred embodiment of the present invention, since the thin-walled portion spreads radially with the center of the top surface of the lid body as the center point, the thin-walled portions are symmetrically arranged with respect to the center of the top surface of the lid body, which is the most easily deformed part, so that the load is evenly applied to the lid body.

[0017] Also, according to the cartridge for water purifier in another preferred embodiment of the present invention, with the thickness of the portion other than the thin-walled portion on the top surface being t and the thickness of the thinnest part of the thin-walled portion being 0.3t or more and 0.7t or less, it is possible to satisfy the pressure resistance strength of the cartridge for water purifier with a further safety factor based on the maximum operating water pressure and the usage period.

[0018] Further, according to a preferred cartridge for a water purifier according to another aspect of the present invention, an inner lid that partitions the lid body and the filter material is disposed between the lid body and the filter material. This inner lid has a watertight engagement portion that is watertightly engaged with the cartridge case, and a flange portion that protrudes radially upward from the upper portion of the watertight engagement portion. Let the height of the cylindrical portion of the lid body be L1 and the length from the upper surface of the inner lid to the upper surface of the flange portion be L2. Since L1 > L2 is satisfied, the top surface of the lid body and the upper surface of the inner lid do not come into contact with each other, and it is possible to prevent the inner lid from contacting the thin-walled portion of the lid body where the strength of the lid body is weak.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0020] Embodiment examples of the present invention will be described based on the drawings. FIG. 1 is a longitudinal sectional view of a cartridge for a water purifier according to an embodiment of the present invention. FIG. 2 is a front view of a faucet-connecting type water purifier in which the cartridge for a water purifier according to an embodiment of the present invention is connected to a main body switch. The arrows represent the flow of water, the arrow directed toward the main body switch 20 represents raw water, and the arrow emerging from the purified water outlet 12 of the cartridge 1 for a water purifier represents purified water.

[0021] Each member constituting the cartridge 1 for a water purifier will be described. The cartridge 1 for a water purifier is formed by a bottomed cylindrical cartridge case 2 with an open upper end and a lid body 3 fixed to the upper end opening of the cartridge case 2. A hollow fiber membrane bundle 9 and granular filter media 10 are housed in the internal space formed thereby.

[0022] The cartridge case 2 has a raw water inlet 11 on the side surface near the lower end and a purified water outlet 12 at the center of the lower end surface. On the inner surface of the lower end portion of the cartridge case 2, a cylindrical portion is provided for fitting the end portion on the side having the opening of the hollow fiber membrane bundle 9 of the hollow fiber membrane module 18 so as to surround the purified water outlet 12. A bayonet mechanism for connecting to the main body switch 20 is provided around the inlet opening of the raw water inlet 11.

[0023] The hollow fiber membrane module 18 houses a hollow fiber membrane bundle 9 formed by bundling a predetermined number of hollow fiber membranes and bent into an inverted U shape inside a substantially cylindrical inner cylinder 4. The inner surface of the lower end side of the inner cylinder 4, the lower end side of the hollow fiber membrane bundle 9, and the lower end sides of the hollow fiber membranes are sealed and fixed with a potting material such as polyurethane or epoxy resin. The lower end surface of the hollow fiber membrane bundle 9 is open and faces the purified water outlet 12. As the material of the hollow fiber membrane, hydrophilized polysulfone is preferably used. A combination of a plurality of types of hollow fiber membranes with different materials may also be used. If a hydrophobic polyethylene or polypropylene hollow fiber membrane is inserted, air mixed in the water can be efficiently discharged. Although the hollow fiber membrane bundle 9 is bent into an inverted U shape, it may be a linear hollow fiber membrane bundle whose upper end opening is sealed with an adhesive or heat fusion.

[0024] The inner cylinder 4 is made of synthetic resin and consists of a cylindrical support cylinder 31 and a non-woven fabric 33. A plurality of lattice-shaped openings 32 are provided on the circumferential surface of the support cylinder 31, and the non-woven fabric 33 is fixed so as to cover the openings 32. The non-woven fabric 33 has the function of preventing the facing granular filter medium 10 from leaking and allowing the water to be treated to pass through. The mesh size of the non-woven fabric 33 is smaller than the particle size of the granular filter medium 10.

[0025] The outer cylinder 5 is made of synthetic resin and consists of a cylindrical support cylinder 34 and a non-woven fabric 36. Similar to the inner cylinder 4, a plurality of lattice-shaped openings 35 are provided on the circumferential surface of the support cylinder 34, and the non-woven fabric 36 is fixed so as to cover the openings 35. The non-woven fabric 36 has the function of preventing the facing granular filter medium 10 from leaking and allowing the water to be treated to pass through. The mesh size of the non-woven fabric material 36 is smaller than the particle size of the granular filter medium 10.

[0026] There is a reduced-diameter portion at the lower end of the outer cylinder 5, which is fitted to the outer periphery near the lower end of the inner cylinder 4. That is, a cylindrical space is formed by the outer cylinder 5 and the inner cylinder 4 so that the granular filter medium 10 described later can be filled.

[0027] The outer peripheral surface of the lower end of the outer cylinder 5 has a plurality of convex portions 5a discretely arranged radially outward. The plurality of convex portions 5a contact the inner wall surface of the cartridge case 2, and by more reliably forming and holding the gap 14, a raw water flow path can be ensured, the pressure loss can be reduced, and the flow rate of the cartridge can be maximized.

[0028] The granular filter medium 10 is filled in the cylindrical space formed by the inner cylinder 4 and the outer cylinder 5 described above. As the granular filter medium 10, activated carbon made from coconut shells, ion exchangers suitable for removing lead, etc. can be used in appropriate combinations. When the particle size is reduced, the surface area increases, and the adsorption capacity and ion exchange capacity can be enhanced. It is preferable to adopt a filter medium with an average particle size of 30 to 150 μm.

[0029] In the manufacturing process, granular filter media 10 is filled between the upper end of the inner cylinder 4 and the upper end of the outer cylinder 5. During filling, vibration and air intake are used for the granular filter media 10 to increase the filling density to 0.50 - 0.75 g / mL, enhancing the filtering capacity as a water purifier cartridge. After filling is completed, an elastic member 8 is placed on top of the granular filter media 10, and then an inner lid 6 is further fitted from above. When the elastic member 8 is in close contact with the granular filter media 10 and the inner lid 6, raw water will not short-circuit through the granular filter media 10 (i.e., raw water will not pass between the elastic member 8 and the granular filter media 10). As the elastic member 8, polyolefin foam or silicone rubber can be used.

[0030] The inner lid 6 is disc-shaped and has a concave portion 6a at the center, a cylindrical portion 6b at the outer periphery, and a flange portion 6c that protrudes radially from the cylindrical portion 6b. The concave portion 6a is watertightly engaged with the inner peripheral surface near the upper end of the inner cylinder 4 via an O-ring 37, preventing raw water that does not contact the granular filter media 10 from reaching the hollow fiber membrane bundle 9 inside the inner cylinder 4.

[0031] The cylindrical portion 6b of the inner lid 6 is watertightly engaged with the inner peripheral surface near the upper end of the cartridge case 2 via an O-ring 38. The cylindrical portion 6b, the flange portion 6c, and the O-ring 38 constitute a watertight engagement portion that is watertightly engaged with the cartridge case. That is, the internal space formed by the lower surface of the inner lid 6 and the cartridge case 2 is the water receiving portion, and the upper surface side of the inner lid 6 is the non-water receiving portion. Although the inner lid 6 and the cartridge 2 must withstand water pressure, since the strength of the inner lid 6 is designed to be smaller than that of the cartridge 2, if damage occurs, it will be the inner lid 6. It is preferable to use a transparent ABS resin, AS resin, or acrylic resin for the material of the inner lid 6. Using a transparent resin for the inner lid 6 allows confirmation that there are no abnormalities during assembly.

[0032] The lid 3 consists of a disc-shaped top surface portion 3a and a cylindrical portion 3b having an outer diameter smaller than the outer diameter of the top surface portion 3a that hangs down from the peripheral edge of the top surface portion 3a. A thin portion 3c is formed on the surface of the top surface portion 3a facing the inside of the cartridge case. The cylindrical portion 3b is fixed to the inner peripheral surface near the opening of the cartridge case 2. Since the lid 3 and the cartridge case 2 are fixed and integrated, the strength is high. When water flows through the water purifier cartridge 1, water pressure is applied to the space formed by the lower surface of the inner lid 6 and the cartridge case 2, and a force is applied to the inner lid 6 to pull it upward. The upper surface of the flange portion 6c of the inner lid 6 contacts the lower end of the cylindrical portion 3b of the lid, but the lid 3 does not come off from the cartridge case 2. FIG. 6 is an enlarged view of the upper part of the water purifier cartridge according to an embodiment of the present invention. As shown in FIG. 6, since the height L1 of the cylindrical portion 3b of the lid is longer than the length L2 from the upper surface of the inner lid 6 to the upper surface of the flange portion 6c, the upper surface of the inner lid 6 does not contact the top surface of the lid 3. Since the strength of the welded portion between the lid 3 and the cartridge case 2 is designed to be higher than the strength of the inner lid 6, if damage occurs, the inner lid 6 will be damaged first.

[0033] Fig. 3(a) is a perspective view of the lid 3 viewed from below, (b) is a bottom view, and (c) is a cross-sectional view taken along line A-A shown in the bottom view. Four thin portions 3c are provided on the surface of the top surface portion 3a of the lid 3 facing the inside of the cartridge case. Taking the inner diameter of the cylindrical portion 3b of the lid 3 as D and the center of the top surface portion 3a as the center of the circle, the thin portion 3c is outside the circle with a diameter of 0.05D and crosses the range from the circle with a diameter of 0.07D to the circle with a diameter of 0.8D. The four thin portions 3c spread radially with the center of the top surface portion 3a as the center point. Two of the thin portions 3c are arranged diagonally with the center of the top surface portion in between, and the remaining two are arranged at positions rotated by 90°. As shown in FIG. 3, taking the thickness of the part other than the thin part of the top surface portion as t, the thickness of the thinnest part of the thin part is 0.3t or more and 0.7t or less. Considering the pressure resistance, the cross-sectional shape of the thin portion 3c is not sharp and is preferably an inverted U shape. Since the thin portion 3c is provided on the surface of the top surface portion 3a facing the inside of the cartridge case, it cannot be seen from above. It is extremely rare for the user to be aware of the thin portion 3c, which is preferable in terms of appearance.

[0034] As shown in FIG. 4, the thin portion 3d may have a shape with eight locations. As shown in FIG. 5, in a perspective view seen from below, the thin portion 3e may have a shape like the Chinese character "く" and be arranged symmetrically with respect to a line passing through the center of the top surface.

[0035] When the cylindrical portion 3b of the lid body 3 is welded to the vicinity of the opening and the inner peripheral surface of the cartridge case 2 by ultrasonic welding, it is preferable because the lid body 3 is firmly fixed to the cartridge case 2. However, a male screw may be provided on the cylindrical portion 3b, a female screw may be provided on the vicinity of the opening and the inner peripheral surface of the cartridge case 2, and fastening may be performed with screws.

[0036] The use of the water purifier cartridge 1 configured as described above will be described. The raw water that enters from the raw water inlet 11 is guided to the cylindrical gap 14, passes through the outer cylinder 5, the granular filter medium 10, and the inner cylinder 4 in that order in the radial direction, and reaches the hollow fiber membrane bundle 9. By contacting the granular filter medium 10, free residual chlorine, mold odor, trihalomethane, lead, etc. in the raw water are removed. Next, the turbidity of the water is removed by the hollow fiber membrane bundle 9 to become purified water, which is discharged from the purified water outlet 12.

[0037] Since the amount of filtered water that the filter medium can process is limited, the user continues to use the water purifier while periodically replacing the water purifier cartridge. Each time the faucet of the water purifier is opened and closed, a water pressure load is applied, and when the clogging of the filter medium progresses, the water pressure increases. However, since it is replaced with a new water purifier cartridge when the filtering function deteriorates, it will not lead to damage.

[0038] However, if the user neglects to replace the cartridge and uses it significantly beyond the assumed service life, the clogging of the filter medium progresses more than expected, and a water pressure load exceeding the maximum operating water pressure is applied, and the number of times of the water pressure load significantly exceeds the assumption. In such a case, in the water purifier cartridge 1 of the present invention, when the lid 3 can no longer withstand the repeated water pressure load, small cracks will form from the thin-walled portion 3c provided in the lid 3, leading to damage to the cartridge. The leaked water only comes out weakly from the cracks, and the user can see it and notice that the use has exceeded the assumed service life by a large margin.

Example

[0039] [Example 1] The bottomed cylindrical cartridge case has a wall thickness of 3.6 mm and an inner diameter of the opening of 54 mm. The lid has a top surface thickness of 3 mm, an outer diameter of the top surface of 59 mm, an outer diameter of the cylindrical portion of 55 mm (including the welding mark of ultrasonic welding), an inner diameter of the cylindrical portion of 50 mm, and a height of the cylindrical portion of 8.5 mm. The thin-walled portions are provided at four locations in the range from a circle with a diameter of 11 mm to a circle with a diameter of 37 mm with the center of the top surface of the lid as the center of the circle. Two of the thin-walled portions are arranged diagonally across the center of the top surface, and the remaining two are arranged at positions rotated by 90° on the surface of the top surface facing the inside of the cartridge case. The thickness of the thinnest part of the thin-walled portion is 1 mm. The thickness of the concave portion of the inner lid is 0.7 mm, and the length from the upper surface of the inner lid to the upper surface of the flange portion is 8 mm. Granular activated carbon and a polysulfone hollow fiber membrane were used for the filter medium. The filter medium was filled between the inner cylinder and the outer cylinder inside the cartridge case, and an elastic member and an inner lid were mounted in order. Finally, the lid was fixed near the opening of the cartridge case by ultrasonic welding to form a water purifier cartridge.

[0040] This cartridge for a water purifier was attached to a durability test apparatus, and pressurization and depressurization were repeated using the electromagnetic valve on the upstream side of the raw water inlet. As a result, the cartridge for the water purifier did not break until 4,000 cycles. At this point, it was assumed that the cartridge for the water purifier needed to be replaced. However, pressurization and depressurization were further repeated until breakage occurred. As a result, cracks appeared in the lid at 6,000 cycles and water leaked. At this time, the cartridge case did not break, and cracks occurred at the location corresponding to the thin-walled part of the lid, and only a small amount of water leaked weakly, and the filter material did not scatter around, nor did the water spurt out.

[0041] [Comparative Example 1] A cartridge for a water purifier identical to that of Example 1 was manufactured, except that a thin-walled part was not provided on the top surface of the lid.

[0042] This cartridge for a water purifier was attached to a durability test apparatus, and pressurization and depressurization were repeated using the electromagnetic valve on the upstream side of the raw water inlet in the same manner as in Example 1. As a result, the cartridge for the water purifier did not break until 4,000 cycles. At this point, it was assumed that the cartridge for the water purifier needed to be replaced. However, pressurization and depressurization were further repeated until breakage occurred. As a result, cracks appeared in the inner lid at 6,000 cycles, and cracks appeared at the joint between the top surface part and the cylindrical part of the lid at 9,000 cycles. The filter material did not scatter around, but water spurted out from the cracks in the lid.

Explanation of Reference Numerals

[0043] 1 Cartridge for water purifier 2 Cartridge case 3 Lid 3a Top surface part 3b Cylindrical part 3c Thin-walled part 3d Thin-walled part 3e Thin-walled part 4 Inner cylinder 5 Outer cylinder 5a Protrusion 6 Inner lid 6a Recess 6b Cylindrical part 6c Flange part 8 Elastic member 9 Hollow fiber membrane bundle 10 Granular filter medium 11 Raw water inlet 12 Clean water outlet 14 Gap 18 Hollow fiber membrane module 20 Body switch 31 Support cylinder 32 Opening 33 Non-woven fabric 34 Support cylinder 35 Opening 36 Non-woven fabric 37 O-ring 38 O-ring D Inner diameter of the cylindrical part L1 Height of the cylindrical part L2 Length from the upper surface of the inner lid to the upper surface of the flange part

Claims

1. A cartridge for a water purifier, comprising: a bottomed cylindrical cartridge case; a filter medium housed inside the cartridge case; and a lid fixed near an opening of the cartridge case, wherein the lid has a disk-shaped top surface portion and a cylindrical portion hanging down from a peripheral edge portion of the top surface portion, and a thin-wall portion with a small thickness is formed on a surface of the top surface portion facing the inside of the cartridge case. A cartridge for a water purifier.

2. With the inner diameter of the cylindrical portion being D and the center of the top surface portion being the center of a circle, the thin-wall portion is located outside a circle with a diameter of 0.05D and crosses a range from a circle with a diameter of 0.07D to a circle with a diameter of 0.8D. The cartridge for a water purifier according to Claim 1.

3. The thin-wall portion spreads radially with the center of the top surface portion as a center point. The cartridge for a water purifier according to Claim 1 or 2.

4. With the thickness of the top surface portion other than the thin-wall portion being t, the thickness of the thinnest portion of the thin-wall portion is 0.3t or more and 0.7t or less. The cartridge for a water purifier according to any one of Claims 1 to 3.

5. An inner lid is disposed between the lid and the filter medium to partition the lid and the filter medium. The inner lid has a watertight engagement portion that engages with the cartridge case in a watertight manner, and a flange portion protruding radially upward from an upper portion of the watertight engagement portion. With the height of the cylindrical portion being L1 and the length from the upper surface of the inner lid to the upper surface of the flange portion being L2, the cartridge for a water purifier according to any one of Claims 1 to 4 satisfies L1 > L2.

6. A water purifier equipped with the cartridge for a water purifier according to any one of Claims 1 to 5.

Images