An air cleaner assembly and design method

Abstract

The application relates to an air filter assembly and a design method, and relates to the technical field of engine intake systems. A guide pipe is arranged in a lower shell, the length of the guide pipe is set according to target noise, and the included angle is determined according to the length and shell parameters. The guide pipe guides airflow to the central area of a filter element, makes the main airflow uniformly diffuse, avoids local rapid blockage, significantly improves the dust holding capacity of the filter element, and prolongs the replacement period. Meanwhile, the guide pipe increases airflow resistance along the path, consumes gas energy, and effectively reduces intake pneumatic noise. The assembly adopts a support plate matched with multiple connecting supports to realize multi-point support, uniformly disperses weight and vibration load, prevents shaking and loosening, and improves installation stability. Independent supports optimize the vibration transmission path, facilitate independent design of modes to avoid excitation frequencies, reduce resonance risks, attenuate vibration transmission to a vehicle body, and improve the NVH performance of the vehicle. The problems of short service life, high noise caused by uneven airflow distribution, poor fixing and damping, and low support mode are solved.

Description

Technical Field

[0001] This invention relates to the field of engine intake system technology, specifically to an air filter assembly and its design method. Background Technology

[0002] The air filter assembly is a key component of a car engine's intake system. Its main function is to filter impurities, dust, and particulate matter from the air entering the engine, preventing cylinder wear and ensuring the engine's normal operating performance and lifespan. A typical air filter assembly usually includes a housing, a filter element housed within the housing, and a mounting bracket for securing the assembly to the vehicle body or engine compartment.

[0003] In existing technology, the function of an automotive intake system is to provide clean air to the engine. It generally consists of an intake manifold, an air filter, and an intake pipe. The intake manifold introduces outside air into the air filter, where it is filtered and then enters the engine. The air filter assembly typically uses a split structure, mainly comprising an upper housing, a lower housing, and a filter element assembly housed between them. The upper and lower housings are mostly made of engineering plastics and molded using injection molding. They are sealed and fixed together by peripheral clips, bolts, or spring clips, forming a closed intake chamber. The filter element assembly is usually composed of folded filter paper, sealed at both ends with polyurethane foam, and installed in a designated position within the housing, dividing the chamber into a dirty air chamber and a clean air chamber. The intake manifold of the air filter assembly is usually directly connected to the side of the lower or upper housing. After entering the housing chamber through the intake manifold, the airflow flows directly to the filter element surface. The air inlet of an air filter is usually located in a certain part of the housing (depending on the overall layout). After the air enters, it is filtered by the filter screen and then enters the air pipe from the air outlet.

[0004] However, in common air filter assemblies, the airflow is unevenly distributed after entering the housing, directly impacting local areas of the filter element. This may cause dust to accumulate too quickly in those areas, forming local blockages, shortening the replacement cycle and lifespan of the air filter assembly. Furthermore, high-speed airflow can easily generate aerodynamic noise when entering the housing and flowing through the filter element, which can affect the overall NVH performance of the vehicle and impact the user experience. Summary of the Invention

[0005] This application provides an air filter assembly and design method, which can solve the problem that in common air filter assemblies in the prior art, the airflow is unevenly distributed after entering the housing, directly impacting local areas of the filter element. This may cause dust to accumulate too quickly in the area, forming local blockages, shortening the replacement cycle and service life of the air filter assembly. In addition, high-speed airflow is prone to generating aerodynamic noise when entering the housing and flowing through the filter element, which can easily affect the NVH performance of the whole vehicle and affect the user experience.

[0006] Poor vibration damping at the mounting points of the air filter assembly or the absence of vibration damping measures leads to increased vibration and noise in the assembly; the mounting bracket of the air filter assembly has an excessively low modal value or a complex structural design to improve the modal value.

[0007] In a first aspect, embodiments of this application provide an air filter assembly, comprising: The outer casing includes an upper casing and a lower casing, with an air inlet pipe provided on the outer side of the lower casing; A filter element is disposed at the opening of the lower housing, and the upper housing presses against the filter element on the side away from the lower housing, so as to cooperate with the lower housing to clamp the filter element; An air guide tube is disposed inside the lower housing. One end of the air guide tube is connected to the air inlet tube. The air guide tube has a set length, and the length direction of the air guide tube has a set angle with the length direction of the lower housing.

[0008] In one embodiment, a mounting bracket is further included, the mounting bracket comprising: Support plate, which is used to connect to the vehicle body; Multiple connecting brackets are disposed on the support plate, and the upper end of the connecting brackets is connected to the lower housing.

[0009] In one embodiment, the lower housing is provided with mounting seats that correspond one-to-one with the connecting brackets in the circumferential direction. The mounting seat has a slot in the middle, and a sleeve is inserted in the slot. A bolt passes through the sleeve and is fixed on the connecting bracket to connect the lower housing and the connecting bracket.

[0010] In one embodiment, a shock-absorbing pad is further provided in the slot, and the shock-absorbing pad is sleeved on the outside of the sleeve and located between the sleeve and the inner wall of the slot.

[0011] In one embodiment, the support plate is provided with a support plate reinforcing rib, and one of the connecting brackets has a cross-section in the shape of a "Z" and the support plate reinforcing rib passes through the bottom of the connecting bracket.

[0012] In one embodiment, the upper housing is provided with a plurality of square pins, and the lower housing is provided with pin sleeves that correspond one-to-one with the square pins, the square pins and pin sleeves cooperating to form a fixing point.

[0013] Secondly, this application also provides a method for designing an air filter assembly, which is used to design the above-mentioned air filter assembly, including the following steps: Based on the current noise level and the preset target noise level, the set length of the air duct is obtained; Based on the set length of the air duct and the structural parameters of the lower shell, the set included angle of the air duct is obtained.

[0014] In one embodiment, after obtaining the set included angle of the air duct based on the set length of the air duct and the structural parameters of the lower housing, the method further includes: Based on the structural parameters of the lower shell, the maximum length of the air duct is obtained; If the set length of the air guide tube is greater than the maximum length of the air guide tube, the maximum length of the air guide tube shall be used as the set length, and the resistance parameter of the inner wall of the air guide tube shall be adjusted.

[0015] In one embodiment, adjusting the resistance parameter of the inner wall of the air guide tube includes: Based on the noise value corresponding to the maximum length of the air duct and the preset target noise value, the noise difference is obtained; Based on the noise difference, the frictional resistance change along the airflow through the air duct is obtained; Based on the change in frictional resistance of the airflow through the air duct, adjust the contact area between the inner wall of the air duct and the airflow and / or adjust the resistance coefficient of the inner wall of the air duct.

[0016] In one embodiment, obtaining the set included angle of the air duct based on the set length of the air duct and the structural parameters of the lower housing includes: Based on the set length of the air guide tube and the structural parameters of the lower shell, the range of the set included angle of the air guide tube is obtained; Based on the structural parameters of the lower shell, the angle corresponding to the maximum cancellation value of the airflow reflection in the air guide tube is obtained; If the angle corresponding to the maximum cancellation value of the airflow reflection in the air duct is outside the set angle selection range of the air duct, the angle value closest to the angle corresponding to the maximum cancellation value of the airflow reflection in the air duct within the set angle selection range of the air duct is selected as the set angle of the air duct.

[0017] The beneficial effects of the technical solutions provided in this application include: In designing this air filter assembly, the outer casing includes an upper casing and a lower casing. An air inlet pipe is located on the outer side of the lower casing, and the filter element is positioned at the opening of the lower casing. The upper casing presses against the filter element on the side furthest from the lower casing to cooperate with the lower casing in holding the filter element. An air guide pipe is located inside the lower casing, with one end connected to the air inlet pipe. The air guide pipe has a predetermined length, and its length direction forms a predetermined angle with the length direction of the lower casing. During the design process: based on the current noise level and a preset target noise level, the predetermined length of the air guide pipe is obtained; based on the predetermined length of the air guide pipe and the structural parameters of the lower casing, the predetermined angle of the air guide pipe is obtained. By setting an air guide pipe with a predetermined length and angle inside the lower casing, the flow direction and outlet position of the airflow after entering the lower casing chamber can be precisely controlled. The combination of the predetermined length and angle of the air guide pipe can guide the outlet to a specific optimized area on the filter element surface, allowing the main airflow to diffuse evenly from the center outwards. Compared to existing technologies where intake airflow directly impacts localized areas of the filter element, causing rapid blockage, this solution allows for more even dust accumulation on the filter element surface, significantly increasing the filter's dust holding capacity and thus extending the air filter assembly's replacement cycle and lifespan. The increased length of the air duct enhances the airflow path within the duct, increasing the friction area between the airflow and the duct wall, thereby increasing airflow resistance, consuming some gas energy, and effectively reducing aerodynamic noise generated by the intake airflow. This solution addresses the common problem in existing air filter assemblies where uneven airflow distribution after entering the housing directly impacts localized areas of the filter element, potentially leading to rapid dust accumulation and blockage, shortening the air filter assembly's replacement cycle and lifespan. Furthermore, the high-speed airflow entering the housing and flowing through the filter element easily generates aerodynamic noise, potentially affecting the vehicle's NVH performance and impacting the user experience.

[0018] The structure employing a support plate and multiple connecting brackets achieves multi-point support between the air filter assembly and the vehicle body. Compared to traditional single-point or few-point fixing methods, multi-point support can more evenly distribute the weight of the assembly and the vibration load during operation, effectively preventing the air filter assembly from shaking, shifting, or loosening under vehicle bumps or engine vibrations, significantly improving the stability and overall rigidity of the installation connection. Furthermore, the independent mounting brackets serve as transitional connectors between the air filter assembly and the vehicle body, optimizing the vibration transmission path. With the support plate connected to the vehicle body and the connecting brackets connected to the lower housing, this structure facilitates independent design and optimization of the bracket's modal characteristics, ensuring its natural frequencies avoid common excitation frequencies of the engine and vehicle body, reducing resonance risks, and thus blocking or attenuating vibration transmission to the vehicle frame, further improving the overall NVH performance of the vehicle. This solves the problems of poor vibration damping at the fixing points of the air filter assembly or the lack of vibration damping measures in existing technologies, leading to increased assembly vibration and noise; and the problems of excessively low modal characteristics or complex structural designs for the air filter assembly mounting brackets to improve modal characteristics. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of an embodiment of an air filter assembly according to the present invention.

[0021] Figure 2 This is a schematic diagram of the mounting bracket in an embodiment of an air filter assembly according to the present invention.

[0022] Figure 3 This is a schematic diagram of the outer casing in an embodiment of an air filter assembly according to the present invention.

[0023] Figure 4 This is a schematic diagram of the upper housing structure in an embodiment of an air filter assembly according to the present invention.

[0024] Figure 5 This is a schematic diagram of the lower housing structure in an embodiment of an air filter assembly according to the present invention.

[0025] Figure 6 This is a schematic diagram of the air duct structure in an embodiment of an air filter assembly according to the present invention.

[0026] Figure 7 This is a schematic diagram of a connecting bracket in an embodiment of an air filter assembly according to the present invention.

[0027] Figure 8 This is a schematic diagram of the filter element in an embodiment of an air filter assembly according to the present invention.

[0028] In the diagram: 1. Outer shell; 11. Upper shell; 111. Square pin; 112. Air outlet pipe; 113. Upper retaining seat; 12. Lower shell; 121. Air inlet pipe; 122. Mounting seat; 1221. Slot; 123. Pin sleeve; 124. Lower retaining seat; 2. Filter element; 3. Air guide pipe; 4. Mounting bracket; 41. Support plate; 411. Support plate reinforcing rib; 42. Connecting bracket; 5. Sleeve; 6. Shock-absorbing pad; 7. Snap ring. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0030] This application provides an air filter assembly and design method, which can solve the problem that in common air filter assemblies in the prior art, the airflow is unevenly distributed after entering the housing, directly impacting local areas of the filter element. This may cause dust to accumulate too quickly in the area, forming local blockages, shortening the replacement cycle and service life of the air filter assembly. In addition, high-speed airflow is prone to generating aerodynamic noise when entering the housing and flowing through the filter element, which can easily affect the NVH performance of the whole vehicle and affect the user experience.

[0031] Poor vibration damping at the mounting points of the air filter assembly or the absence of vibration damping measures leads to increased vibration and noise in the assembly; the mounting bracket of the air filter assembly has an excessively low modal value or a complex structural design to improve the modal value.

[0032] like Figure 1 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 8 As shown, in one aspect, this application provides an air filter assembly, which includes: The outer casing 1 includes an upper casing 11 and a lower casing 12, with an air inlet pipe 121 provided on the outer side of the lower casing 12; The filter element 2 is disposed at the opening of the lower housing 12, and the upper housing 11 presses against the side of the filter element 2 away from the lower housing 12 to cooperate with the lower housing 12 to clamp the filter element 2. The air guide tube 3 is located inside the lower housing 12. One end of the air guide tube 3 is connected to the air inlet tube 121. The air guide tube 3 has a set length, and the length direction of the air guide tube 3 has a set angle with the length direction of the lower housing 12.

[0033] In designing this air filter assembly, the outer casing 1 includes an upper casing 11 and a lower casing 12. An air inlet pipe 121 is located on the outer side of the lower casing 12. The filter element 2 is positioned at the opening of the lower casing 12. The upper casing 11 presses against the side of the filter element 2 away from the lower casing 12 to cooperate with the lower casing 12 in holding the filter element 2. An air guide pipe 3 is located inside the lower casing 12, with one end connected to the air inlet pipe 121. The air guide pipe 3 has a set length, and the length direction of the air guide pipe 3 forms a set angle with the length direction of the lower casing 12. During the design process: based on the current noise level and a preset target noise level, the set length of the air guide pipe 3 is obtained; based on the set length of the air guide pipe 3 and the structural parameters of the lower casing 12, the set angle of the air guide pipe 3 is obtained. By providing an air guide pipe 3 with a set length and a set angle inside the lower casing 12, the flow direction and outlet position of the airflow after entering the lower casing 12 chamber can be precisely controlled. The designed length and angle of the air guide tube 3, when combined, guide the air outlet to a specific optimized area on the surface of the filter element 2, allowing the main airflow to diffuse evenly from the center outwards. Compared to existing technologies where the intake airflow directly impacts localized areas of the filter element, causing rapid localized blockage, this solution results in more uniform dust accumulation on the filter element surface, significantly increasing the filter element's dust holding capacity and thus extending the replacement cycle and lifespan of the air filter assembly. The designed length of the air guide tube 3 increases the airflow path within the tube, increasing the friction area between the airflow and the tube wall, thereby increasing the airflow resistance along the path, consuming some gas energy, and effectively reducing aerodynamic noise generated by the intake airflow. This solves the common problem in existing air filter assemblies where uneven airflow distribution after entering the housing directly impacts localized areas of the filter element, potentially leading to rapid dust accumulation and localized blockage, shortening the replacement cycle and lifespan of the air filter assembly. Furthermore, high-speed airflow entering the housing and flowing through the filter element easily generates aerodynamic noise, which can affect the overall vehicle NVH performance and impact the user experience.

[0034] In this example, the upper shell 11 has reinforcing ribs on both its inner and outer sides, while the lower shell 12 has vertical reinforcing ribs and mesh reinforcing ribs. The cross-section of the air duct 3 is triangular, with rounded corners at each end. The purpose of the rounded corners is to reduce abrupt changes in the airway and avoid generating sharp airflow noise. The upper shell 11 is equipped with an air outlet pipe 112.

[0035] like Figure 1 and Figure 2 As shown, in some optional embodiments, a mounting bracket 4 is also included, which includes: Support plate 41, which is used to connect to the vehicle body; Multiple connecting brackets 42 are mounted on the support plate 41, and the upper end of the connecting brackets 42 is connected to the lower housing 12.

[0036] In this embodiment, the air filter assembly also includes a mounting bracket 4, which comprises a support plate 41 and multiple connecting brackets 42. The support plate 41 is used to connect to the vehicle body; the multiple connecting brackets 42 are disposed on the support plate 41, and the upper end of the connecting brackets 42 is connected to the lower housing 12. The structure of the support plate 41 and multiple connecting brackets 42 achieves multi-point support between the air filter assembly and the vehicle body. Compared with traditional single-point or few-point fixing methods, multi-point support can more evenly distribute the weight of the assembly and the vibration load during operation, effectively preventing the air filter assembly from shaking, shifting, or loosening under vehicle bumps or engine vibration, significantly improving the stability and overall rigidity of the installation connection. Furthermore, the independent mounting bracket 4 serves as a transitional connector between the air filter assembly and the vehicle body, optimizing the vibration transmission path. The support plate 41 is connected to the vehicle body, and the connecting bracket 42 is connected to the lower housing 12. This structure facilitates the independent design and optimization of the bracket's own modes, so that its natural frequency avoids the common excitation frequencies of the engine and the vehicle body, reducing the risk of resonance, thereby blocking or attenuating the transmission of vibration to the vehicle body frame, and further improving the NVH performance of the whole vehicle.

[0037] like Figure 1 , Figure 2 and Figure 5 As shown, in some optional embodiments, the lower housing 12 is provided with mounting seats 122 corresponding to the connecting brackets 42 in the circumferential direction. The mounting seat 122 is provided with a slot 1221 in the middle. A sleeve 5 is inserted in the slot 1221. Bolts pass through the sleeve 5 and are fixed on the connecting brackets 42 to connect the lower housing 12 and the connecting brackets 42.

[0038] In this embodiment, the lower housing 12 is provided with mounting seats 122 corresponding to the connecting brackets 42 in the circumferential direction. A slot 1221 is provided in the middle of the mounting seat 122, and a sleeve 5 is fitted into the slot 1221. Bolts pass through the sleeve 5 and are fixed to the connecting brackets 42 to connect the lower housing 12 and the connecting brackets 42. The sleeve 5 serves as an intermediate force transmission medium between the bolt and the mounting seat 122 of the lower housing 12, bearing the axial clamping force when the bolt is tightened. This structure avoids the metal bolt directly pressing against the plastic mounting seat 122, effectively preventing cracking, deformation, or creep loosening of the mounting seat 122 due to localized stress concentration, ensuring the integrity and durability of the connection structure, and extending the service life of the assembly. The slot 1221 in the middle of the mounting seat 122 can pre-position and clamp the sleeve 5. During assembly, the sleeve 5 can be pre-locked in the slot 1221 to prevent it from falling off. Assembly workers do not need to support the sleeve 5 while tightening bolts, achieving self-fixation of the sleeve 5, reducing assembly difficulty, and significantly improving assembly efficiency on the production line. The sleeve 5, positioned within the slot 1221 and serving as a passageway for the bolts, forms a physical isolation interface between the metal bolts and the lower housing 12. Combined with the material properties of the sleeve 5, it can buffer and absorb some of the vibration energy from the connecting bracket 42, reducing the direct transmission of vibration to the air filter housing, helping to reduce abnormal noises caused by structural resonance, and further improving the overall NVH performance of the vehicle.

[0039] like Figure 1 and Figure 5 As shown, in some optional embodiments, a shock-absorbing pad 6 is also provided in the slot 1221. The shock-absorbing pad 6 is sleeved on the outside of the sleeve 5 and located between the sleeve 5 and the inner wall of the slot 1221.

[0040] In this embodiment, a shock-absorbing pad 6 is also provided inside the slot 1221. The shock-absorbing pad 6 is sleeved on the outside of the sleeve 5 and located between the sleeve 5 and the inner wall of the slot 1221. The shock-absorbing pad 6 can effectively absorb and attenuate the high-frequency vibration energy transmitted from the engine or body, blocking the direct transmission path of vibration to the air filter housing. This structure not only reduces the structural noise generated by the vibration of the housing, but also avoids abnormal noise caused by the relative movement between the housing and the bracket, significantly improving the NVH performance of the entire vehicle. During vehicle operation, the air filter assembly is subjected to continuous vibration and impact. Without the shock-absorbing pad 6, the sleeve 5 and the inner wall of the plastic slot 1221 are prone to hard friction and collision, which will lead to wear, fraying, or even cracking of the inner wall of the slot 1221 over a long period of time. After setting the shock-absorbing pad 6, soft isolation is achieved, eliminating the risk of hard contact, protecting the structural integrity of the mounting base 122, and extending the service life of the assembly.

[0041] like Figure 2As shown, in some optional embodiments, the support plate 41 is provided with a support plate reinforcing rib 411, and one of the connecting brackets 42 has a cross-section of a "Z" shape, with the support plate reinforcing rib 411 partially passing through the bottom of the connecting bracket 42.

[0042] In this embodiment, the support plate 41 is provided with a support plate reinforcing rib 411, and one of the connecting brackets 42 has a Z-shaped cross-section, with the support plate reinforcing rib 411 partially passing under the connecting bracket 42. The Z-shaped cross-section of the connecting bracket 42 itself has high bending stiffness, and together with the reinforcing rib on the support plate 41, especially the design of the reinforcing rib passing under the connecting bracket 42, a composite reinforcement structure is formed. This structure significantly improves the local stiffness of the support plate 41 near the connection point and the overall stiffness of the bracket assembly, effectively increasing the natural frequency of the bracket assembly, allowing it to avoid common excitation frequencies of the engine and body, reducing the risk of resonance, and thus significantly improving the NVH performance of the entire vehicle. Furthermore, the support plate reinforcing rib 411 passing under the Z-shaped connecting bracket 42 makes full use of the space inside the cross-section of the connecting bracket 42, avoiding interference between the reinforcing rib and the connecting bracket 42 in planar arrangement. This allows for the maintenance of structural strength without increasing the overall height or width of the bracket assembly, which is beneficial for the compact layout of the engine compartment and conforms to the design trend of vehicle lightweighting and miniaturization.

[0043] like Figure 2 and Figure 7 As shown, in this example, there are three connecting brackets 42. The support plate reinforcing rib 411 is H-shaped, which can improve the modal strength of the support plate 41 by about 1 MPa. One of the remaining two connecting brackets 42 has a Z-shaped cross-section and four point-like reinforcing ribs. Another connecting bracket 42 also has a Z-shaped cross-section and four point-like reinforcing ribs, which can improve the modal strength of the connecting bracket 42 by about 0.5 MPa. The other connecting bracket 42 includes a support portion and a connecting portion. The support portion has flanges on both sides, V-shaped reinforcing ribs and straight reinforcing ribs, and point-like reinforcing ribs at the connection between the support portion and the connecting portion. The edge of the connecting portion has flanges, which together can improve the modal strength by about 2 MPa. The connecting portion also has a process groove to avoid quality defects such as wrinkles, cracks, and deformation caused by material extrusion during part stamping. The design positions of the reinforcing ribs and flanges are obtained through CAE analysis. The aforementioned reinforcing ribs and flanges can together improve the modal strength by about 4 MPa.

[0044] like Figure 4 and Figure 5 As shown, in some optional embodiments, the upper housing 11 is provided with a plurality of square pins 111, and the lower housing 12 is provided with pin sleeves 123 corresponding to the square pins 111 one by one. The square pins 111 and the pin sleeves 123 cooperate to form a fixing point.

[0045] In this embodiment, the upper housing 11 is provided with multiple square pins 111, and the lower housing 12 is provided with pin sleeves 123 corresponding to the square pins 111. The square pins 111 and pin sleeves 123 cooperate to form fixing points. The mating surfaces of the square pins 111 and pin sleeves 123 are non-circular, possessing inherent anti-rotation characteristics. During the fastening process of the upper housing 11 and lower housing 12, the cooperation of the square pins 111 and pin sleeves 123 effectively restricts the relative circumferential rotation between the two, ensuring that the upper housing 11 and lower housing 12 maintain a precise angular positional relationship after assembly. This is crucial for ensuring the docking accuracy of the air intake and exhaust pipes with the vehicle's piping, avoiding piping installation stress caused by housing misalignment. Furthermore, the square pin structure has higher shear strength, resisting multidimensional vibration loads generated during vehicle operation and preventing fretting wear or loosening between the upper housing 11 and lower housing 12. The distributed design of multiple fixing points further evens out the stress at the connection, improving the overall rigidity of the housing connection.

[0046] like Figure 3 , Figure 4 and Figure 5 As shown, in this example, after the square pin 111 and the pin sleeve 123 cooperate to form a fixing point, the upper retaining seat 113 on the upper housing 11 and the lower retaining seat 124 on the lower housing 12 are fixed by the retaining spring 7.

[0047] like Figure 1 As shown, on the other hand, this application also provides a design method for an air filter assembly, which is used to design the above-mentioned air filter assembly, including the following steps: Based on the current noise level and the preset target noise level, the set length of the air duct 3 is obtained; Based on the set length of the air duct 3 and the structural parameters of the lower shell 12, the set included angle of the air duct 3 is obtained.

[0048] In designing this air filter assembly, the outer casing 1 includes an upper casing 11 and a lower casing 12. An air inlet pipe 121 is located on the outer side of the lower casing 12. The filter element 2 is positioned at the opening of the lower casing 12. The upper casing 11 presses against the side of the filter element 2 away from the lower casing 12 to cooperate with the lower casing 12 in holding the filter element 2. An air guide pipe 3 is located inside the lower casing 12, with one end connected to the air inlet pipe 121. The air guide pipe 3 has a set length, and the length direction of the air guide pipe 3 forms a set angle with the length direction of the lower casing 12. During the design process: based on the current noise level and a preset target noise level, the set length of the air guide pipe 3 is obtained; based on the set length of the air guide pipe 3 and the structural parameters of the lower casing 12, the set angle of the air guide pipe 3 is obtained. By providing an air guide pipe 3 with a set length and a set angle inside the lower casing 12, the flow direction and outlet position of the airflow after entering the lower casing 12 chamber can be precisely controlled. The designed length and angle of the air guide tube 3, when combined, guide the air outlet to a specific optimized area on the surface of the filter element 2, allowing the main airflow to diffuse evenly from the center outwards. Compared to existing technologies where the intake airflow directly impacts localized areas of the filter element, causing rapid localized blockage, this solution results in more uniform dust accumulation on the filter element surface, significantly increasing the filter element's dust holding capacity and thus extending the replacement cycle and lifespan of the air filter assembly. The designed length of the air guide tube 3 increases the airflow path within the tube, increasing the friction area between the airflow and the tube wall, thereby increasing the airflow resistance along the path, consuming some gas energy, and effectively reducing aerodynamic noise generated by the intake airflow. This solves the common problem in existing air filter assemblies where uneven airflow distribution after entering the housing directly impacts localized areas of the filter element, potentially leading to rapid dust accumulation and localized blockage, shortening the replacement cycle and lifespan of the air filter assembly. Furthermore, high-speed airflow entering the housing and flowing through the filter element easily generates aerodynamic noise, which can affect the overall vehicle NVH performance and impact the user experience.

[0049] In some optional embodiments, after obtaining the set included angle of the air duct 3 based on the set length of the air duct 3 and the structural parameters of the lower housing 12, the method further includes: Based on the structural parameters of the lower shell 12, the maximum length of the air duct 3 is obtained; If the set length of the air guide tube 3 is greater than the maximum length of the air guide tube 3, the maximum length of the air guide tube 3 shall be used as the set length, and the resistance parameter of the inner wall of the air guide tube 3 shall be adjusted.

[0050] In this embodiment, after obtaining the set included angle of the air duct 3 based on its set length and the structural parameters of the lower housing 12, the method further includes: obtaining the maximum length of the air duct 3 based on the structural parameters of the lower housing 12; if the set length of the air duct 3 is greater than its maximum length, the maximum length of the air duct 3 is used as the set length, and the resistance parameter of the inner wall of the air duct 3 is adjusted. By obtaining and verifying the maximum length of the air duct 3 based on the structural parameters of the lower housing 12, interference between the designed air duct 3 and the internal structure of the lower housing 12, the filter element 2, or other components due to excessive length can be effectively avoided. This ensures the feasibility of the design scheme in physical space, reduces the cost of design changes and mold modifications caused by layout conflicts in the later stages, and is particularly suitable for vehicle platforms with compact engine compartment layout space, improving the success rate of the design. When the air duct 3 cannot reach its theoretical optimal length (set length) due to space constraints, compensation is made by adjusting the resistance parameter of the inner wall of the air duct 3. This means that the total energy consumption level can be maintained by increasing the frictional resistance per unit length while shortening the length. This compensation mechanism ensures that even in a less-than-ideal layout space, sufficient gas energy can still be consumed to achieve the preset target noise level, thus avoiding the need to sacrifice NVH performance due to space constraints.

[0051] In some optional embodiments, adjusting the resistance parameters of the inner wall of the air guide tube 3 includes: Based on the noise value corresponding to the maximum length of the air duct 3 and the preset target noise value, the noise difference is obtained; Based on the noise difference, the frictional resistance change value of the air duct 3 through the airflow is obtained; Based on the change in frictional resistance of the airflow through the air duct 3, adjust the contact area between the inner wall of the air duct 3 and the airflow and / or adjust the resistance coefficient of the inner wall of the air duct 3.

[0052] In this embodiment, adjusting the resistance parameters of the inner wall of the air duct 3 specifically includes: obtaining a noise difference based on the noise value corresponding to the maximum length of the air duct 3 and a preset target noise value; obtaining the change in frictional resistance of the air duct 3 through the airflow based on the noise difference; and adjusting the contact area between the inner wall of the air duct 3 and the airflow and / or adjusting the resistance coefficient of the inner wall of the air duct 3 based on the change in frictional resistance of the airflow through the air duct 3. Adjusting the contact area or resistance coefficient of the inner wall provides a second dimension of control in addition to length. This means that even on vehicle platforms with limited space where long air ducts cannot be arranged, the same noise reduction effect can still be achieved by optimizing the inner wall structure, significantly improving the adaptability of the design scheme to different vehicle platforms and the degree of design freedom. A quantitative mapping relationship between noise difference, frictional resistance change, and structural parameters is established. By calculating the difference between the noise value at the maximum length and the target noise value, the amount of frictional resistance change that needs to be compensated is accurately determined. This transforms the design process from trial and error based on experience to data-driven, precise compensation. Even when the length of the air duct 3 is limited and cannot reach the theoretical optimal value, the noise reduction loss caused by insufficient length can be compensated by precisely adjusting the inner wall parameters, ensuring that the noise value of the final product is strictly controlled within the preset target range, thus improving the success rate of the design.

[0053] In some optional embodiments, obtaining the set included angle of the air duct 3 based on the set length of the air duct 3 and the structural parameters of the lower housing 12 includes: Based on the set length of the air duct 3 and the structural parameters of the lower shell 12, the range of the set included angle of the air duct 3 is obtained. Based on the structural parameters of the lower shell 12, the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 is obtained; If the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 is outside the set angle selection range of the air duct 3, the angle value closest to the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 within the set angle selection range of the air duct 3 shall be selected as the set angle of the air duct 3.

[0054] In this embodiment, based on the set length of the air duct 3 and the structural parameters of the lower housing 12, the set angle of the air duct 3 is obtained. Specifically, this includes: obtaining the selection range of the set angle of the air duct 3 based on the set length of the air duct 3 and the structural parameters of the lower housing 12; obtaining the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 based on the structural parameters of the lower housing 12; if the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 is outside the selection range of the set angle of the air duct 3, the angle value closest to the angle corresponding to the maximum cancellation value of airflow reflection in the air duct 3 within the selection range of the set angle of the air duct 3 is selected as the set angle of the air duct 3. When the theoretically optimal noise reduction angle (the angle corresponding to the maximum cancellation value) exceeds the physically feasible range, by selecting the closest angle within the range as the set angle, it is ensured that the noise reduction effect brought by airflow reflection interference is preserved as much as possible under limited space conditions. This optimal selection strategy in a suboptimal solution maximizes the balance between the contradiction between layout space and NVH performance. By pre-determining the selection range of the included angle based on the length of the air duct 3 and the structural parameters of the lower housing 12, angle schemes that would cause interference between the air duct 3 and the internal structure of the lower housing 12, the filter element 2, or other components can be eliminated in the early stages of design. This avoids problems such as assembly difficulties, component damage, or obstruction of airflow channels caused by unreasonable angle design, ensuring the engineering feasibility of the design scheme and the safety of production assembly.

[0055] In this example, the angle of the air duct 3 creates a specific relative position between the air outlet and the side wall of the lower housing 12. The reflected airflow after impacting the side wall interferes with and cancels out the subsequent pulse airflow, further reducing intake whistling noise. This combined noise reduction method effectively reduces intake noise and improves the overall NVH performance of the vehicle without significantly affecting engine power output and fuel economy. The distance between the air outlet and the side wall of the lower housing 12 is less than 70mm.

[0056] In this example, the air duct 3 is set at an angle of approximately 35° and has a length of approximately 190 mm, which increases the dust holding capacity of the filter element 2 by approximately 80% compared to a solution without an air duct.

[0057] In the description of this application, it should be noted that the terms "upper," "lower," 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 application and simplifying the description, and 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 of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0058] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An air filter assembly, characterized in that, comprising: a housing (1), which includes an upper shell (11) and a lower shell (12), wherein an air inlet pipe (121) is arranged on the outer side of the lower shell (12); a filter element (2), which is arranged at the opening of the lower shell (12), wherein the upper shell (11) is pressed against the side of the filter element (2) away from the lower shell (12), so as to cooperate with the lower shell (12) to clamp the filter element (2); an air guide pipe (3), which is arranged on the inner side of the lower shell (12), wherein one end of the air guide pipe (3) is communicated with the air inlet pipe (121), the air guide pipe (3) has a set length, and a set included angle is formed between the pipe length direction of the air guide pipe (3) and the length direction of the lower shell (12).

2. An air filter assembly as described in claim 1, characterized in that, Further comprising a mounting bracket (4), wherein the mounting bracket (4) includes: a support plate (41), which is used for connecting with a vehicle body; a plurality of connecting brackets (42), which are arranged on the support plate (41), wherein the upper end of each connecting bracket (42) is connected with the lower shell (12).

3. An air filter assembly as described in claim 2, characterized in that, Mounting seats (122) in one-to-one correspondence with the connecting brackets (42) are arranged in the circumferential direction of the lower shell (12), a clamping groove (1221) is formed in the middle of each mounting seat (122), a sleeve (5) is clamped in the clamping groove (1221), and a bolt passes through the sleeve (5) and is fixed on the connecting bracket (42), so as to connect the lower shell (12) and the connecting bracket (42).

4. An air filter assembly as described in claim 3, characterized in that, A damping soft pad (6) is further arranged in the clamping groove (1221), and the damping soft pad (6) is sleeved on the outer side of the sleeve (5) and located between the sleeve (5) and the inner wall of the clamping groove (1221).

5. An air filter assembly as described in claim 2, characterized in that, Support plate reinforcing ribs (411) are arranged on the support plate (41), wherein one of the connecting brackets (42) has a several-shaped cross section, and part of the support plate reinforcing rib (411) passes under this connecting bracket (42).

6. An air filter assembly as described in claim 1, characterized in that, A plurality of square pins (111) are arranged on the upper shell (11), pin sleeves (123) in one-to-one correspondence with the square pins (111) are arranged on the lower shell (12), and the square pins (111) and the pin sleeves (123) cooperate to form fixing points.

7. A design method for an air filter assembly, characterized in that, A method for designing the air filter assembly according to any one of claims 1 to 6, comprising the following steps: acquiring the set length of the air guide pipe (3) based on the current noise value and a preset target noise value; acquiring the set included angle of the air guide pipe (3) based on the set length of the air guide pipe (3) and the structural parameters of the lower shell (12).

8. The air filter assembly design method as described in claim 7, characterized in that, After the step of acquiring the set included angle of the air guide pipe (3) based on the set length of the air guide pipe (3) and the structural parameters of the lower shell (12), the method further comprises: acquiring the maximum length of the air guide pipe (3) based on the structural parameters of the lower shell (12); If the set length of the air guide pipe (3) is greater than the maximum length of the air guide pipe (3), taking the maximum length of the air guide pipe (3) as the set length, and adjusting the resistance parameter of the inner wall of the air guide pipe (3).

9. The air filter assembly design method as described in claim 8, characterized in that, The step of adjusting the resistance parameter of the inner wall of the air guide pipe (3) comprises: Based on the noise value corresponding to the maximum length of the air duct (3) and the preset target noise value, the noise difference is obtained; Based on the noise difference, the frictional resistance change value of the air duct (3) through the airflow is obtained; Based on the change in frictional resistance of the airflow through the air duct (3), the contact area between the inner wall of the air duct (3) and the airflow and / or the resistance coefficient of the inner wall of the air duct (3) are adjusted.

10. The air filter assembly design method as described in claim 7, characterized in that, The method of obtaining the set included angle of the air duct (3) based on the set length of the air duct (3) and the structural parameters of the lower shell (12) includes: Based on the set length of the air guide tube (3) and the structural parameters of the lower shell (12), the set angle selection range of the air guide tube (3) is obtained; Based on the structural parameters of the lower shell (12), the angle corresponding to the maximum cancellation value of the airflow reflection of the air duct (3) is obtained; If the angle corresponding to the maximum cancellation value of the airflow reflection of the air duct (3) is outside the set angle selection range of the air duct (3), the angle value closest to the angle corresponding to the maximum cancellation value of the airflow reflection of the air duct (3) within the set angle selection range of the air duct (3) is selected as the set angle of the air duct (3).

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