Hydrophilic folding filter element and filter

Abstract

The hydrophilic folding filter element comprises a center rod and a shell which are coaxially arranged and are of a porous structure, and an upper end cover and a lower end cover which are fixedly arranged at the two ends of the shell and the center rod, a folding filter membrane at least comprises a filter material layer, the filter material layer is folded to form folds, and the head end and the tail end of the filter material layer are welded to form an annular structure; the filter further comprises welding connecting pieces, the filter material layer and the welding connecting pieces are made of the same hydrophilic material, and the upper end and the lower end of the filter material layer are in welding connection with the upper end cover and the lower end cover through the welding connecting pieces. According to the scheme, the filter material layer is connected with the upper end cover and the lower end cover through the welding connecting pieces, the welding connecting pieces can achieve fixed connection between the filter material layer and the upper end cover and between the filter material layer and the lower end cover, completeness of the filter element is guaranteed, and meanwhile the filter material layer can be separated from the upper end cover and the lower end cover. The upper and lower end covers are prevented from flowing to the filtering surface of the filtering material layer due to melting during hot-melt welding, and the effective filtering area of the filtering material layer is ensured.

Description

Technical Field

[0001] This utility model relates to the field of filtration technology, specifically to a hydrophilic pleated filter element and filter. Background Technology

[0002] In liquid handling processes across various industries, including food and beverage, chemical, bioengineering, pharmaceuticals, electronics, and environmental protection, filters are used extensively with different filter media. In the field of liquid sterilization, pleated microporous membrane filter cartridges are commonly used. Microporous membranes are made of polymer materials and have excellent chemical compatibility and high filtration capacity. However, due to the low intermembrane support strength, low temperature resistance, and strong hydrophobic properties of microporous membranes, pleated filter cartridges suffer from drawbacks such as low dirt holding capacity, short service life, and low flow rate, which limit their application range and fail to meet customer requirements.

[0003] For example, patent application CN 105879691A discloses a microporous membrane filter element with an asymmetric membrane structure, which includes a central rod with a porous structure arranged coaxially, a shell, and an upper end cap and a lower end cap fixed at both ends of the shell and the central rod. A pleated filter membrane is arranged around the central rod in the cavity between the central rod and the shell. It adopts a complete hot-melt welding structure, which makes the connection between the central rod, the shell, the upper and lower end caps and the pleated filter membrane firm and has good sealing performance. The pleated filter membrane is a hydrophilic microporous membrane, which has a large flow rate, strong dirt holding capacity and low wetting difficulty while ensuring sterilization performance.

[0004] However, in the microporous membrane filter cartridges mentioned above, the filter membrane is made of polyethersulfone, which has good hydrophilicity, while the supporting and connecting structures such as the central rod, outer shell, and upper and lower end caps are all made of polypropylene, which does not have hydrophilicity.

[0005] Polyethersulfone typically has a melting point above 200°C, while polypropylene typically has a melting point between 130°C and 180°C. Therefore, when the filter membrane and the upper and lower end caps are hot-melted during the welding of this microporous membrane filter element, the polypropylene end caps are prone to generating more molten liquid due to heat. This molten liquid may flow onto the surface of the filter membrane outside the welded sealing area, causing part of the filter membrane surface to be covered by polypropylene material. Moreover, the hydrophobic properties of polypropylene itself make it difficult for this part of the filter membrane to be wetted during the filtration process, thereby affecting the filtration performance of this part of the filter membrane and reducing the effective filtration area. Utility Model Content

[0006] In order to overcome the shortcomings of the prior art, this utility model provides a hydrophilic pleated filter element and filter.

[0007] The technical solution adopted by this utility model is as follows: a hydrophilic pleated filter element, including a central rod with a porous structure arranged coaxially, a shell, and an upper end cap and a lower end cap fixed at both ends of the shell and the central rod. A pleated filter membrane is provided between the central rod and the shell, which is distributed around the central rod. The pleated filter membrane includes at least one layer of filter material, which is folded to form pleats. The two ends of the filter material layer are welded together to form a ring structure.

[0008] The filter material layer is provided with welding connecting pieces at both ends. The filter material layer and the welding connecting pieces are made of the same hydrophilic material. The filter material layer is welded to the upper and lower end caps through the welding connecting pieces. The welding connecting pieces not only connect the filter material layer to the upper and lower end caps, but also act as a barrier to reduce the flow of molten liquid generated by the hot melting of the upper and lower end caps to the surface of the filter material layer during the welding process.

[0009] Preferably, the folded filter membrane further includes at least one support layer, which is folded together with the filter material layer to form pleats. Sealing aids are welded to both ends of the support layer, and these sealing aids are made of the same hydrophilic material as the filter material layer. The sealing aids at both ends of the support layer are welded to the ends of the filter material layer to form an integral structure. These sealing aids not only serve as a welding connection between the filter material layer and the support layer, but also act as a barrier, reducing the flow of molten liquid from the hot melting of the support layer onto the surface of the filter material layer during welding.

[0010] Preferably, the height of the support layer is smaller than that of the filter material layer, and there is a gap between the upper and lower ends of the support layer and the welding connecting piece. Therefore, when the support layer and the welding connecting piece are hot-melted, the support layer will not be heated and melted, ensuring that the support layer will not generate molten liquid that affects the adjacent filter material layer, thereby further ensuring product quality.

[0011] Preferably, the hydrophilic material is any one of hydrophilic PES, hydrophilic PTFE, and hydrophilic PVDF.

[0012] This utility model also provides a filter comprising the above-mentioned hydrophilic pleated filter element.

[0013] The beneficial effects of this utility model are as follows: By adopting the above solution, the filter material layer is connected to the upper and lower end caps by an additional welding connecting piece. The welding connecting piece can not only achieve a fixed connection between the filter material layer and the upper and lower end caps to ensure the integrity of the filter element, but also separate the filter material layer from the upper and lower end caps, reducing the amount of molten material from the upper and lower end caps flowing onto the filter surface of the filter material layer during hot-melt welding, thus ensuring the effective filtration area of ​​the filter material layer. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the hydrophilic pleated filter element according to Embodiment 1 of this utility model.

[0015] Figure 2 for Figure 1 Enlarged diagram of point A in the middle.

[0016] Figure 3 for Figure 1 A schematic diagram of the cross-sectional structure along the BB direction.

[0017] Figure 4 for Figure 3 Enlarged diagram of point C in the middle.

[0018] Figure 5 This is a cross-sectional structural diagram of the folded filter membrane according to Embodiment 1 of this utility model.

[0019] Figure 6 This is a schematic diagram of the structure of the filter in Embodiment 2 of this utility model. Detailed Implementation

[0020] The embodiments of this utility model will be further described below with reference to the accompanying drawings. Example 1

[0021] like Figures 1-5 As shown, a hydrophilic pleated filter element includes a central rod 1, a shell 2, an upper end cap 3, a lower end cap 4, and a pleated filter membrane 5.

[0022] The central rod 1, outer shell 2, upper end cover 3, and lower end cover 4 are all made of polypropylene. The central rod 1 and outer shell 2 are hollow and have porous surfaces. The central rod 1 and outer shell 2 are coaxially arranged. The upper end cover 3 and lower end cover 4 are respectively fixed at the upper and lower ends of the central rod 1 and outer shell 2.

[0023] The folded filter membrane 5 is folded to form pleats, and its two ends are sealed and welded together to form a ring structure. It is positioned between the central rod 1 and the outer shell 2. The upper and lower ends of the folded filter membrane 5 are respectively sealed to the upper end cap 3 and the lower end cap 4. The folded filter membrane 5 includes at least a filter material layer 51 and a support layer 52. The filter material layer 51 is made of a hydrophilic material, such as hydrophilic PES, hydrophilic PTFE, or hydrophilic PVDF. The support layer 52 can be made of polypropylene. For ease of illustration, only one layer of the filter material layer 51 and support layer 52 is shown in the accompanying drawings. However, the filter material layer and support layer are not limited to a single layer; they can be arranged in multiple layers, with the filter material layer and support layer arranged alternately.

[0024] A welding connecting piece 6 is also provided between the pleated filter membrane 5 and the upper end cover 3 and the lower end cover 4. The welding connecting piece 6 and the filter material layer 51 of the pleated filter membrane 5 are made of the same hydrophilic material. During welding, the welding connecting piece 6 can be heat-melted and welded to the upper and lower ends of the pleated filter membrane 5 first, and then the upper end cover 3 and the lower end cover 4 can be heat-melted and welded to the welding connecting pieces 6 at the upper and lower ends of the pleated filter membrane 5 respectively. Alternatively, the welding connecting piece 6 can be heat-melted and welded to the upper end cover 3 and the lower end cover 4 first, and then the upper end cover 3 and the lower end cover 4 can be heat-melted and welded to the upper and lower ends of the pleated filter membrane 5 respectively. In other words, in this embodiment, the folded filter membrane 5 is connected to the upper end cover 3 and the lower end cover 4 by an additionally provided welding connecting piece 6. Since the welding connecting piece 6 and the filter material layer 51 are made of the same hydrophilic material and have the same melting point, the welding connecting piece 6 and the filter material layer 51 can be better fused and fixed during hot-melt welding, thereby forming a more stable and reliable sealed connection, ensuring the integrity of the filter element. At the same time, after the two are hot-melt welded, the same hydrophilic properties of the welding connecting piece 6 and the filter material layer 51 ensure that the filter material layer 51 can be fully wetted, thereby ensuring the effective filtration area of ​​the filter material layer 51. In addition, the welding connecting piece 6 also acts as a barrier, separating the filter material layer 51 from the upper end cover 3 and the lower end cover 4, preventing the molten liquid from the upper end cover and the lower end cover from flowing onto the filter surface of the filter material layer after heating.

[0025] Furthermore, the height of the support layer 52 is smaller than that of the filter material layer 51, and there is a gap between the upper and lower ends of the support layer 52 and the welding connecting piece 6. Therefore, when the welding connecting piece 6 is hot-melt welded to the folded filter membrane 5, only the filter material layer 51 is hot-melt welded to the welding connecting piece 6, while the two ends of the support layer 52 will not be melted by heat. This avoids the support layer 52 from being melted by heat and affecting the adjacent filter material layer 51, thus further ensuring product quality.

[0026] In addition, sealing aids 53 are provided between the beginning and end ends of the support layer 52 and the beginning and end ends of the filter material layer 51. The sealing aids 53 are also made of the same hydrophilic material as the filter material layer 51. During welding, the sealing aids 53 are sandwiched between the support layer 52 and the filter material layer 51 at both ends of the folded filter membrane 5, and then heat-fused together using a heating wire to form a single unit. The sealing aids 53 not only serve as a welding connection between the filter material layer 51 and the support layer 52, but also act as a barrier, reducing the flow of molten liquid from the hot-melting of the support layer 52 onto the surface of the filter material layer during welding. Example 2

[0027] like Figure 6As shown, a filter includes a filter housing and a hydrophilic pleated filter element disposed within the filter housing, wherein the hydrophilic pleated filter element is the hydrophilic pleated filter element described in Example 1.

[0028] In the description of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0030] Attention all technical personnel: Although this utility model has been described according to the specific embodiments above, the inventive concept of this utility model is not limited to this utility model. Any modification that utilizes the inventive concept will be included within the scope of protection of this patent right.

Claims

1. A hydrophilic folded filter element, comprising a center rod (1), an outer shell (2) and upper and lower end caps (3, 4) fixed to the ends of the center rod and the outer shell, the center rod (1) and the outer shell (2) being provided with a folded filter membrane (5) distributed around the center rod (1); the folded filter membrane (5) comprises at least one layer of filter material (51), the layer of filter material (51) being folded to form pleats, the layer of filter material (51) being welded at its ends to form a ring structure. characterized in that The layer of filter material (51) and the welding tabs (6) are made of the same hydrophilic material, and the layer of filter material (51) is welded to the upper and lower end caps (3, 4) via the welding tabs (6).

2. The hydrophilic pleated cartridge of claim 1, wherein: The folded filter membrane (5) further comprises at least one layer of support material (52), the layer of support material (52) being folded together with the layer of filter material (51) to form pleats, and the ends of the layer of support material (52) are welded to the auxiliary sealing tabs (53). The auxiliary sealing tabs (53) are made of the same hydrophilic material as the layer of filter material (51), and the auxiliary sealing tabs (53) at the ends of the layer of support material (52) are welded to the ends of the layer of filter material (51) to form an integral structure.

3. The hydrophilic pleated cartridge of claim 2, wherein: The height of the layer of support material (52) is smaller than the height of the layer of filter material (51), and there is a gap between the ends of the layer of support material (52) and the welding tabs (6).

4. The hydrophilic pleated cartridge of claim 2, wherein: The hydrophilic material is any one of hydrophilic PES, hydrophilic PTFE and hydrophilic PVDF.

5. A filter characterized by: The hydrophilic folded filter element of any one of claims 1-4. The hydrophilic folded filter element of any one of claims 1-4.

Images