Multifunctional long-acting composite filter element

Abstract

The application discloses a multifunctional long-acting composite filter element and belongs to the technical field of lubricating oil filtration, which comprises an upper core body assembly and a lower core body assembly; the upper core body assembly comprises a non-woven fabric folded surface area type filtering core body; the lower core body assembly comprises a biomass volumetric filtering core body; the upper core body assembly and the lower core body assembly are combined into a composite filter element with surface area type filtering and volumetric filtering; the upper core body assembly and the lower core body assembly are connected and fixed by a middle cover plate; the inner side central parts of the upper core body assembly and the lower core body assembly are respectively provided with a central pipe; the upper end of the upper core body assembly is fixedly connected with an upper cover plate; and the lower end of the lower core body assembly is fixedly connected with a lower cover plate. Compared with a traditional paper filter element under the same conditions, the multifunctional long-acting composite filter element has the advantages of large flow, small pressure difference, good filtering fineness, high filtering efficiency, long service life and the function of repairing lubricating oil, thereby greatly prolonging the service life of the lubricating oil.

Description

Technical Field

[0001] This invention relates to the field of lubricating oil filtration technology, specifically to a multifunctional long-lasting composite filter element. Background Technology

[0002] The filtration technology industry offers a wide variety of oil filters. Currently, most filters on the market use paper, non-woven fabric, and polymer membrane filter media, and their filtration methods are all surface area filtration. Due to the manufacturing and structural characteristics of the filter media and the limitations of the filtration method, in actual operation, although the pressure difference is small, if the filter element has a high filtration fineness, the filtration efficiency is good and the working effect is good, but it will clog quickly, has a small dirt holding capacity, and a short service life. Conversely, if the filtration fineness is low, the filtration efficiency is low and the working effect is poor, but it is less prone to clogging and has a longer service life.

[0003] CN2017200403745 discloses a volumetric biomass oil purification filter element, including a central tube, an outer layer of fine filter cloth, and an outer layer of knitted filter cloth, all filled with biomass filter media. The advantages of this filter element are high filtration fineness, good filtration efficiency, large dirt holding capacity, and long service life. However, its disadvantages include high filtration resistance (i.e., high pressure differential) and relatively low flow rate. It cannot meet the mechanical requirements of low-power oil pumps, meaning its application range and conditions are significantly limited. Therefore, in the current field of filtration technology, the contradiction between filtration fineness, filtration efficiency, dirt holding capacity, service life, flow rate, and pressure differential remains unresolved. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of current internal combustion engine filtration technology, namely the contradictions between the filtration fineness, efficiency and dirt holding capacity, clogging life and flow rate and pressure difference of traditional filter elements. It provides a new type of filter element with a new filtration mode and working mechanism, namely a multi-functional composite filter element, which effectively solves the contradictions between the filtration fineness, filtration efficiency and dirt holding capacity, clogging life and flow rate and pressure difference of traditional filter elements.

[0005] To achieve the above objectives, the present invention proposes a multifunctional long-lasting composite filter element, comprising: an upper core assembly (2) and a lower core assembly (1). The upper core assembly (2) comprises a non-woven fabric folded surface area filter core, and the lower core assembly (1) comprises a biomass volume filter core. The upper core assembly (2) and the lower core assembly (1) are connected in parallel to perform filtration simultaneously, forming a composite filter element.

[0006] The upper core assembly (2) and the lower core assembly (1) are connected and fixed by a middle cover plate (4); the inner central part of the upper core assembly (2) and the lower core assembly (1) are respectively provided with a central tube, and the upper end of the upper core assembly (2) is fixedly connected to an upper cover plate (6), the upper cover plate (6) is provided with an oil outlet (61), and the lower end of the lower core assembly (1) is fixedly connected to a lower cover plate (5).

[0007] Furthermore, the upper core assembly (2) includes an upper core center tube (28), a folded filter cloth layer (26) is mounted on the outside of the upper core center tube (28), a metal support mesh (263) is attached to the inside of the folded filter cloth layer (26), and a metal outer mesh (27) is fitted on the outside of the folded filter cloth layer (26). The metal outer mesh (27), the folded filter cloth layer (26), and the upper end of the upper core center tube (28) are all connected and fixed to the upper cover plate (6). The lower end of the upper core assembly (2) is connected and fixed to the middle cover plate (4).

[0008] Furthermore, the folded filter cloth (26) used in the upper core assembly (2) is thermally composited with inner and outer layers of PET nonwoven filter material (261) and an intermediate layer of PBT nonwoven filter material (262) disposed between the two layers of PET nonwoven filter material (261). The PBT nonwoven filter material (262) is one or more layers. The inner layer of PET nonwoven filter material (261) is tightly bonded to the filter cloth layer metal support mesh (263).

[0009] Furthermore, in the two-layer PET nonwoven filter material (261), the weight of the inner PET nonwoven filter material (261) is 30-40% of the total weight of the two PET layers; the total weight of the inner and outer PET layers is 100-120 g / m², and the weight of the middle PBT nonwoven filter material (262) is 60-80 g / m²; the folded filter cloth (26) made by thermal bonding has a weight of 160-200 g / m² and a thickness of 0.6-1.2 mm.

[0010] Furthermore, the lower core assembly (1) includes a lower core center tube (14), a GP double-layer filter cloth (13) is fitted on the outside of the lower core center tube (14), a volumetric biomass filter element (12) is provided on the outside of the GP double-layer filter cloth (13), a lower core metal outer mesh (11) is fitted on the outside of the biomass filter element (12), and the lower ends of the lower core center tube (14), the GP double-layer filter cloth (13), the biomass filter element (12) and the lower core metal outer mesh (11) are all connected and fixed to the lower cover plate (5), while the upper end of the lower core assembly (1) is connected and fixed to the middle cover plate (4).

[0011] Furthermore, the GP double-layer filter cloth (13) is made of glass fiber and PET composite material, with a weight of 220±30g / ㎡, a thickness of 1.0~1.6mm, an air permeability of ≥900L / ㎡·s, and an average pore size of 80~100μm.

[0012] Furthermore, the height of the upper core assembly (2) accounts for 30%-40% of the total height of the composite filter element.

[0013] Furthermore, the upper cover plate (6) and the lower cover plate (5) can be interchanged to change the oil outlet direction.

[0014] Furthermore, there are multiple upper core components (2) and lower core components (1), and the upper core components (2) and lower core components (1) are arranged in a staggered manner.

[0015] Furthermore, a bypass port (51) is provided on the lower cover plate (5), and a bypass valve is installed at the bypass port (51); when the pressure is too high under special pressure or abnormal conditions, the bypass valve opens, and the oil is discharged directly through the bypass valve, flows through the bypass port (51), and flows out from the oil outlet (61).

[0016] Furthermore, the lower core center tube (14) and the upper core center tube (28) are respectively equipped with a lower inner support spring (15) and an upper inner support spring (29).

[0017] Furthermore, when the composite filter element filters the oil, the oil flows from the outside of the composite filter element to the central tube on the inside.

[0018] Compared with the prior art, the composite filter element of the present invention has the following advantages:

[0019] 1. The composite filter element of this invention connects and fixes a volumetric filtration biomass filter element assembly with a surface area filtration filter element assembly to form a composite filter element. This achieves: ① solving the technical bottlenecks in flow rate, pressure difference, filtration fineness, and service life in the existing filtration field; ② overcoming the shortcomings of traditional filter elements that only perform a single filtration function on engine oil, organically combining oil filtration and repair; ③ optimizing the filtration mode of traditional filter elements. Simultaneously, it greatly extends the service life of engine oil and reduces waste oil emissions, resulting in significant social and economic benefits.

[0020] 2. In this invention, the upper core assembly and the lower core assembly are connected in parallel and perform filtration simultaneously. Compared with traditional filter cartridges, it has the characteristics of large flow rate, small pressure difference, good filtration fineness, and large dirt holding capacity. If only volumetric filter cartridges are used for filtration, the high density and thickness of the filter media (generally around 20mm) of the volumetric filter cartridges result in a large pressure difference between the inlet and outlet, making them unsuitable for certain mechanical conditions. While pleated filter cartridges have thinner filter media (generally around 1mm), although their filtration fineness is insufficient and lubricating oil can pass through easily, the pressure difference between the inlet and outlet is smaller. Therefore, this invention connects pleated and volumetric filter cartridges in parallel. The pleated filter cartridges partially reduce the overall pressure difference across the entire filter cartridge assembly, making this pressure difference applicable to more conditions. Secondly, this invention improves upon existing volumetric filter cartridges by using a double-layer GP filter cloth. This cloth has better air permeability and filtration fineness than existing fine filter cloths, further reducing the pressure difference between the inlet and outlet of the volumetric filter cartridge, thus further reducing the overall pressure difference of the filter cartridge and better adapting to a wider range of mechanical conditions.

[0021] 3. The upper core assembly of this invention utilizes the characteristics and weight ratio of PET and PBT materials, employing a pleated filter layer thermally bonded together with two layers of PET non-woven fabric filter layer and a PBT filter layer positioned between the two PET filter layers. Its air permeability is 750–900 L / m²·s, significantly reducing the resistance to oil flow and lowering the pressure differential.

[0022] 4. The folded filter layer in the upper core assembly of the present invention has an average pore size of 75-80μm and a filtration fineness of 12-15μm, which is high. Moreover, it adopts a three-layer structure of PET+PBT+PET, which increases the dirt holding capacity, has good temperature resistance, and has a long service life.

[0023] a. Due to the good temperature resistance of PET (polyethylene terephthalate) (265-280℃), the pleated filter layer can be used for a long time in the high-temperature environment of internal combustion engine oil, avoiding the carbonization phenomenon caused by long-term use of ordinary paper filters.

[0024] b. Because PBT (polybutylene terephthalate) has a temperature resistance (225-235℃) between two PET layers, its structure is "sandwich sponge", and its dirt holding capacity is greater than that of a single-layer paper filter paper of the same thickness. In contrast, the filter paper layer of traditional paper filter cartridges, at the same thickness, has (1) an air permeability ≤480L / ㎡·s. (2) an average pore size of 80-95 and a filtration fineness of 20-30μm.

[0025] 5. The volumetric biomass filter element assembly of this invention uses GP double-layer filter cloth, with a weight of 220±30 g / m², a thickness of 1.0±0.2 mm, an air permeability ≥900 L / m²·s, and an average pore size of 80–100 μm. In contrast, the volumetric biomass filter element disclosed in CN2017200403745 uses fine filter cloth with a weight of 100±30 g / m², a thickness of 1 mm, an air permeability of 110–410 L / m²·s, and an average pore size of 135 μm. This demonstrates that the filter cloth layer near the central tube, by increasing air permeability and reducing the average pore size, not only reduces pressure differential and increases flow rate but also effectively improves filtration fineness.

[0026] 6. This invention also increases the dosage without changing the weight of the biomass filter media, making it more effective at repairing engine oil and increasing its dirt-holding capacity.

[0027] In summary, compared with ordinary paper filter elements, the non-woven pleated filter element assembly in the composite filter element of the present invention has higher filtration fineness, better filtration effect, larger relative dirt holding capacity, smaller pressure drop, larger flow rate, longer life and longer-lasting effect. Attached Figure Description

[0028] Figure 1 This is a front sectional view of the composite filter element of the present invention;

[0029] Figure 2 This is a top sectional view of the upper core assembly from the bb direction.

[0030] Figure 3(a) is a partially enlarged schematic diagram of the middle cover plate;

[0031] Figure 3(b) is a sectional view of the middle cover plate;

[0032] Figure 3(c) is a top view of the middle cover plate;

[0033] Figure 4 This is a schematic diagram of the upper and lower core center tubes of the present invention;

[0034] Figure 5 A simplified schematic diagram of the composite core's appearance;

[0035] Figure 6 This is a schematic diagram of the folded filter cloth layer of the upper core assembly;

[0036] Figure 7 This is a schematic diagram illustrating the principle of parallel filtration to reduce pressure difference using composite filter elements of the present invention.

[0037] The meanings of the reference numerals in the attached diagram are as follows: 1: Lower core assembly; 11: Lower core metal outer mesh; 12: Biomass filter element (volume type); 13: GP double-layer filter cloth layer; 14: Lower core central tube (perforated mesh); 15: Lower inner support spring; 2: Upper core assembly; 26: Upper core folded filter cloth layer (surface area type); 261: PET (polyethylene terephthalate); 262: PBT (polybutylene terephthalate); 263: Filter cloth layer metal support mesh; 27: Upper core metal outer mesh; 28: Upper core central tube (perforated mesh); 29: Upper inner support spring; 4: Middle cover plate; 5: Lower cover plate; 51: Pressure opening valve; 6: Upper cover plate; 61: Oil outlet. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0039] According to one embodiment of the present invention, such as Figure 1 As shown, a multifunctional long-lasting composite filter element is provided, including a lower core assembly 1, an upper core assembly 2, a middle cover plate 4, a lower cover plate 5, and an upper cover plate 6.

[0040] The lower cover plate 5 has a lower core assembly (biomass volume filter assembly) 1 fixed on its upper part. The upper end of the lower core assembly 1 is fixedly connected to the middle cover plate 4. The middle cover plate 4 has an upper core assembly 2 (non-woven fabric folded surface area filter assembly) fixedly connected above it. The upper end of the upper core assembly 2 is covered by an upper cover plate 6. That is, the upper core assembly 2 and the lower core assembly 1 are fixedly connected by the middle cover plate 4 set between the two filter assemblies. The lower core assembly 1 is a biomass volume filter assembly, and the upper core assembly 2 is a non-woven fabric folded surface area filter assembly. The inner middle of the upper core assembly 2 and the lower core assembly 1 are provided with flow channels.

[0041] See Figure 2 , Figure 6The upper core assembly (non-woven pleated surface area filter element assembly) 2 includes an upper core central tube 28. A pleated filter cloth layer 26 is fitted onto the outer side of the upper core central tube 28. The pleated filter cloth layer 26 is formed by thermally bonding two layers of PET filter material 261 and three layers of PBT filter material 262 disposed between the two layers of PET filter material 261 at 150℃-200℃, and the thickness of the thermally bonded pleated filter cloth layer 26 is 0.6-1.8mm. A filter cloth layer metal support mesh 263 is attached to the inner side of the pleated filter cloth layer 26. An annular upper core metal mesh 27 is fitted on the outside of the folded filter cloth layer 26. The upper core metal mesh 27 is used to fix the upper core folded filter cloth layer 26. The upper end of the upper core metal mesh 27 and the upper end of the upper core central tube 28 are both fixed to the upper cover plate 6. The lower end of the upper core metal mesh 27 and the lower end of the upper core central tube 28 are both connected and fixed to the middle cover plate 4.

[0042] Among them, the PET filter material 261 in the folded filter cloth layer 26 is PET, polyethylene terephthalate, with a melting point of 265-280℃, preferably below 220℃; the PBT filter paper 262 is PBT, polybutylene terephthalate, with a melting point of 225-235℃, preferably below 140℃.

[0043] like Figure 4 As shown, both the upper core center tube 28 and the lower core center tube 14 are perforated pipes; used to allow the filtered lubricating oil to flow out of the oil outlet 61 through the pipes.

[0044] See Figure 1 , Figure 5 The lower core assembly 1 includes a lower core central tube 14, the lower core central tube 14 is wrapped with a GP double-layer filter cloth 13, a biomass filter element 12 is fitted on the outside of the GP double-layer filter cloth 13, and a lower core metal outer mesh 11 is fitted on the outside of the biomass filter element 12. The lower ends of the lower core central tube 14 and the lower ends of the lower core metal outer mesh 11 are fixed to the lower cover plate 5, and the upper ends of the lower core central tube 14 and the upper ends of the lower core metal outer mesh 11 are fixed to the lower end of the middle cover plate 4.

[0045] Furthermore, the outer side of the GP double-layer filter cloth 13 is provided with multiple biomass filter media rings. The biomass filter media rings are circular and filled with biomass filter media. The multiple biomass filter media rings are fitted onto the outer side of the GP double-layer filter cloth 13 wrapped around the central tube, and stacked to form a biomass filter element 12. The biomass filter element 12 is provided with a lower core metal mesh 11.

[0046] In this invention, the lower core component 1, a volumetric biomass filter element, is surrounded by a GP double-layer filter cloth 13, made of glass fiber and PET composite material. Its weight is 220±30 g / m², thickness is 1.0±0.2 mm, air permeability is ≥900 L / m²·s, and average pore size is 80–100 μm. In contrast, the fine filter cloth used in the volumetric biomass filter element disclosed in patent CN2017200403745 has a weight of 100±30 g / m², thickness of 1 mm, air permeability of 110–410 L / m²·s, and average pore size of 135 μm. Therefore, it can be seen that the GP double-layer filter cloth near the central tube in this invention, by increasing air permeability and reducing average pore size, not only reduces pressure differential and increases flow rate but also effectively improves filtration fineness. Furthermore, without changing the weight of the biomass filter media, the increased dosage results in better oil repair performance and a larger dirt-holding capacity.

[0047] The upper cover plate 6 has an oil outlet 61;

[0048] Preferably, the upper cover plate 6 and the lower cover plate 5 can be interchanged to change the direction of the oil outlet; at the same time, this change will also change the filter element pressure difference to a certain extent.

[0049] According to another embodiment of the present invention, optionally, there are multiple upper core components 2 and lower core components 1, and the upper core components 2 and lower core components 1 are arranged in a staggered manner.

[0050] Preferably, the upper core component 2 accounts for 30%-40% of the total height of the composite filter element.

[0051] Referring to Figures 3(a)-(c), the middle cover plate 5 includes an inner ring plate 43 and an outer ring plate 42. A support plate 44 is connected to the middle of the inner ring plate 43 and the outer ring plate 42. The outer ring plate 42 is fixedly clipped to the lower end of the upper core metal mesh 27 and the upper end of the lower core metal mesh 11. The upper end of the support plate 44 is glued to the upper core folded filter cloth 26, the upper core metal mesh 27, and the upper core central tube 28. The lower end of the support plate 44 is glued to the lower core filter element 12, the lower core metal mesh 11, and the lower core central tube 14. The inner ring plate 43 is clipped to the ends of the lower core central tube 14 and the upper core central tube 28. The lower core central tube 14 and the upper core central tube 28 are respectively equipped with a lower inner support spring 15 and an upper inner support spring 29.

[0052] See Figure 7In this invention, the upper core assembly 2 and the lower core assembly 1 are connected in parallel and perform filtration simultaneously, which can reduce the pressure difference between the inlet and outlet of the filter element. If only a volumetric filter element assembly is used for filtration, the thick filter media of the volumetric filter element can easily lead to a large pressure difference between the inlet and outlet of the filter element, making it unsuitable for certain mechanical working conditions. Although the pleated filter element assembly has insufficient filtration fineness and allows lubricating oil to pass through easily, the thin filter media of the pleated filter element assembly results in a smaller pressure difference between the inlet and outlet. Therefore, this invention connects the pleated filter element assembly and the volumetric filter element assembly in parallel, which can utilize the pleated filter element assembly to partially reduce the overall pressure difference between the inlet and outlet of the filter element assembly, thereby making this pressure difference applicable to more working conditions. Secondly, this invention improves the fine filter cloth inside the volumetric filter element assembly by using GP double-layer filter cloth, which has better air permeability than the previous fine filter cloth, further reducing the pressure difference between the inlet and outlet of the volumetric filter element assembly, thereby further reducing the overall pressure difference of the filter element.

[0053] In use, the oil to be filtered flows through the composite filter element. The oil flows from the outside of the filter element to the inside for filtration. At the same time, the upper core assembly 2 and the lower core assembly 1 are used for filtration. Then, the oil enters the power system side through the oil outlet 61 and the oil outlet pipeline from the upper core central tube 28 and the lower core central tube 14. This invention has the advantages of high filtration fineness, good filtration effect, large flow rate and small pressure difference.

[0054] Although the illustrative specific embodiments of the present invention have been described above to enable those skilled in the art to understand the invention, it should be understood that the invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes will be obvious as long as they are within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of the present invention are protected.

Claims

1. A multifunctional long-lasting composite filter element, characterized in that, include: The upper core assembly (2) and the lower core assembly (1) are provided. The upper core assembly (2) includes a non-woven fabric folded surface area filter core, and the lower core assembly (1) includes a biomass volume filter core. The upper core assembly (2) and the lower core assembly (1) are connected in parallel to perform filtration simultaneously, forming a composite filter element. There are multiple upper core assemblies (2) and lower core assemblies (1). The upper core assembly (2) and the lower core assembly (1) are arranged in a staggered manner. The upper core assembly (2) and the lower core assembly (1) are connected and fixed by a middle cover plate (4); the inner central part of the upper core assembly (2) and the lower core assembly (1) are respectively provided with a central tube, and the upper end of the upper core assembly (2) is fixedly connected to an upper cover plate (6), the upper cover plate (6) is provided with an oil outlet (61), and the lower end of the lower core assembly (1) is fixedly connected to a lower cover plate (5); The upper and lower covers can be swapped to change the direction of the oil outlet; at the same time, this change will also change the pressure difference of the filter element. The upper core assembly (2) includes an upper core central tube (28), a folded filter cloth layer (26) is mounted on the outside of the upper core central tube (28), a folded metal support mesh (263) is attached to the inside of the folded filter cloth layer (26), and a metal outer mesh (27) is fitted on the outside of the folded filter cloth layer (26), and the metal outer mesh (27), the folded filter cloth layer (26), and the upper end of the upper core central tube (28) are all connected and fixed to the upper cover plate (6), and the lower end of the upper core assembly (2) is connected and fixed to the middle cover plate (4); The folded filter cloth layer (26) used in the upper core assembly (2) is made of inner and outer layers of PET nonwoven filter material (261) and an intermediate layer of PBT nonwoven filter material (262) disposed between the two layers of PET nonwoven filter material (261) through thermal bonding. The PBT nonwoven filter material (262) is one or more layers. The inner layer of PET nonwoven filter material (261) is tightly bonded to the metal support mesh (263) of the filter cloth layer. The PET filter material in the folded filter cloth layer 26 is PET, polyethylene terephthalate, with a melting point of 265-280°C. The PBT filter paper 262 is PBT, polybutylene terephthalate, with a melting point of 225-235°C. In the two-layer PET nonwoven filter material (261), the weight of the inner PET nonwoven filter material (261) is 30-40% of the total weight of the two PET layers; the total weight of the inner and outer PET layers is 100-120 g / m³. 2 The weight of the middle layer PBT nonwoven filter material (262) is 60-80 g / m. 2 The pleated filter cloth (26) made by thermal bonding has a strength of 160-200 g / m³. 2 The thickness is 0.6–1.2 mm; The lower core assembly (1) includes a lower core central tube (14), with a GP double-layer filter cloth (13) fitted on the outside of the lower core central tube (14). A volumetric biomass filter element (12) is provided on the outside of the GP double-layer filter cloth (13), and a lower core metal mesh (11) is fitted on the outside of the biomass filter element (12). The lower ends of the lower core central tube (14), the GP double-layer filter cloth (13), the biomass filter element (12), and the lower core metal mesh (11) are all connected and fixed to the lower cover plate (5), while the upper end of the lower core assembly (1) is connected and fixed to the middle cover plate (4). The GP double-layer filter cloth (13) is made of glass fiber and PET composite material, and its weight is 220±30g / m³. 2 Thickness 1.0~1.6mm, air permeability ≥900L / m 2 •s, average pore size 80–100 μm; Among them, the GP double-layer filter cloth near the center tube is used to increase air permeability, reduce average pore size, reduce pressure difference, increase flow rate, and improve filtration fineness.

2. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: The height of the upper core assembly (2) accounts for 30%-40% of the total height of the composite filter element.

3. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: The upper cover plate (6) and the lower cover plate (5) can be interchanged to change the direction of the oil outlet.

4. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: The number of the upper core assembly (2) and the lower core assembly (1) are both multiple, and the upper core assembly (2) and the lower core assembly (1) are arranged in a staggered manner.

5. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: The lower cover plate (5) has a bypass port (51) and a bypass valve is installed at the bypass port (51). When the pressure is too high under special pressure or abnormal conditions, the bypass valve opens and the oil is discharged directly through the bypass valve, flows through the bypass port (51), and flows out from the oil outlet (61).

6. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: The lower core center tube (14) and the upper core center tube (28) are respectively equipped with a lower inner support spring (15) and an upper inner support spring (29).

7. The multifunctional long-lasting composite filter element according to claim 1, characterized in that: When the composite filter element filters the engine oil, the engine oil flows from the outside of the composite filter element to the central tube on the inside.

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