Axial flow fan blade with blade folded edges and axial flow fan

Abstract

The utility model relates to the field of fan equipment, in particular to an axial flow fan blade with blade folding edges and an axial flow fan, which comprise a central hub support and a plurality of blades. The center hub support comprises a shaft sleeve used for being connected with the rotating shaft, and the multiple blades are regularly connected to the center hub support in the circumferential direction. The blade front edge of the blade is bent backwards along the edge of the blade to form a folded edge, and the folded edge is fixed to the back pressure face of the blade front edge in an attached mode. The scheme has the advantages that the blade bending resistance is improved, blade deformation is reduced, noise is lowered, and the fan performance is improved.

Description

Technical Field

[0001] This utility model relates to the field of fan equipment, and in particular to an axial flow fan blade with folded blade edges and an axial flow fan. Background Technology

[0002] Axial flow fans have a wide range of applications in daily life. Axial flow refers to airflow that moves in the same direction as the axis of the fan blades; examples include electric fans and air conditioner outdoor unit fans. Axial flow fans with axial flow blades are typically used in applications requiring high flow rates but low pressure, and are widely used in the air conditioning industry. Common axial flow fans mainly consist of a hub and multiple blades arranged around the hub. Although the structure is simple, the detailed structural parameters of each part of the axial flow fan require very high precision, significantly impacting its operation and noise control.

[0003] In recent years, the detailed design of axial fan blades has been continuously improved. However, most axial fan blades are currently manufactured using one-piece injection molding of plastic, which results in insufficient bending resistance of the blades. During high-intensity operation, the blades are prone to collapse and deformation due to airflow resistance, leading to a series of problems. For example, the impeller airflow decreases, affecting the overall performance of the fan; poor impeller dynamic balance may lead to increased vibration; and increased noise affects the comfort of the user environment.

[0004] Of particular note is that the leading edge of the blade is the first part to cut into the air during operation, bearing significant friction and impact. When airflow is drawn in from this side, the leading edge of the blade interacts violently with the air, making this area more prone to deformation. This not only affects the aerodynamic performance of the blade but may also accelerate fatigue damage and shorten its service life.

[0005] Furthermore, existing axial fan blades often generate significant noise when operating at high speeds. This noise originates not only from friction between the blades and the air but may also stem from airflow turbulence caused by blade deformation. This noise issue is particularly pronounced in applications with stringent noise control requirements, such as ventilation systems in residential air conditioning or office environments.

[0006] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0007] To address the aforementioned problems, the primary objective of this invention is to provide an axial flow fan blade with folded blade edges, which offers advantages such as improved blade bending resistance, reduced blade deformation, lower noise, and enhanced fan performance.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An axial flow fan blade with a folded blade edge has the following technical solution: it includes a central hub support and multiple blades; the central hub support includes a bushing for connecting a rotating shaft, and the multiple blades are regularly connected to the central hub support in a circumferential direction; the leading edge of the blade is bent backward along its edge to form a folded edge, and the folded edge is fitted and fixed to the back pressure surface of the leading edge of the blade.

[0010] Furthermore, this application also proposes that the width of the folded edge gradually increases from the outer edge of the blade to the inner edge of the blade.

[0011] Furthermore, this application also proposes that the trailing edge of the blade is provided with serrations.

[0012] Furthermore, this application also proposes that the central hub bracket is constructed as a metal hub bracket, and the bushing is formed at the center of the central hub bracket; the central hub bracket also includes a plurality of connecting arms arranged circumferentially on the outer side of the central hub bracket, and the blade is connected to the outer end of the connecting arm.

[0013] Furthermore, this application also proposes that the outer end of the connecting arm is attached and fixed to the back pressure surface of the blade.

[0014] Furthermore, this application also proposes that through holes are provided on the outer end of the connecting arm and at the corresponding position of the blade, and the through holes on the connecting arm and the through holes on the blade are aligned and riveted together.

[0015] The second objective of this utility model is to provide an axial flow fan, including the aforementioned axial flow fan blade with folded blade edges.

[0016] As described above, this application provides an axial flow fan blade and an axial flow fan with folded blade edges, comprising a central hub support and multiple blades. The central hub support includes a bushing for connecting a rotating shaft, and the multiple blades are regularly connected to the central hub support circumferentially. The leading edge of each blade is bent backward along its edge to form a folded edge, which is fitted and fixed to the back pressure surface of the leading edge of the blade. By providing a backward-bent folded edge at the leading edge of the blade, the structural strength of the blade is enhanced, the bending resistance of the blade is improved, and the risk of deformation during high-intensity operation is reduced. Simultaneously, the folded edge structure can also optimize airflow and reduce operating noise, thus possessing the advantages of improved blade bending resistance, reduced blade deformation, reduced noise, and improved fan performance. Attached Figure Description

[0017] Figure 1 This application provides a three-dimensional schematic diagram of the pressure surface of an axial flow fan blade.

[0018] Figure 2 This application provides a three-dimensional schematic diagram of the back pressure surface of an axial flow fan blade.

[0019] Figure 3 The present application provides a schematic diagram of the blade structure. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0023] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., 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 according to the specific circumstances.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] Example 1:

[0026] like Figures 1-3 As shown, this embodiment relates to an axial flow fan blade with a folded blade edge, including a central hub support 1 and multiple blades 2. The central hub support 1 includes a bushing 11 for connecting a rotating shaft, and the multiple blades 2 are regularly connected to the central hub support 1 circumferentially. The leading edge 21 of the blades 2 is bent backward along its edge to form a folded edge 22, which is fitted and fixed to the back pressure surface 23 of the leading edge 21. In this design, the central hub support 1 and the multiple blades 2 constitute the basic structure of the axial flow fan blade. The central hub support 1 is connected to the rotating shaft through the bushing 11 to ensure stable rotation of the fan blade. The multiple blades 2 are regularly connected to the central hub support 1 circumferentially to ensure uniform force distribution on the fan blade. The leading edge 21 of the blades is bent backward along its edge to form a folded edge 22, which is fitted and fixed to the back pressure surface 23 of the leading edge 21. With the folded edge 22 on the leading edge 21 of the blades in this design, the strength of the blades 2 is enhanced, and the impeller is less prone to deformation and vibration when rotating at high speed. This invention effectively reduces the deformation of blade 2 caused by airflow friction and impact during operation, thereby improving the durability and operational stability of the wind turbine blade. It also overcomes the problems of reduced impeller airflow, poor impeller dynamic balance, and increased noise caused by blade 2 deformation. Compared with existing technologies, this application significantly enhances the deformation resistance of blade 2 by providing a folded edge 22 at the leading edge 21 of the blade. Especially during high-speed operation, it effectively reduces blade 2 deformation caused by airflow friction and impact, thereby improving the service life and operational stability of the wind turbine blade.

[0027] In this design, the shape of the folded edge 22 can be straight, curved, or other suitable, and the specific shape can be adjusted according to the design requirements of the blade 2. The material of the folded edge 22 can be the same as that of the blade 2, or a higher strength material can be used to further improve the resistance to deformation. The folded edge 22 can be fixed by welding, riveting, or bonding to ensure that the folded edge 22 is in close contact with the back pressure surface 23 of the blade leading edge 21.

[0028] like Figure 2 and 3As shown, in this design, the width of the flange 22 gradually increases from the outer edge 24 to the inner edge 25 of the blade. Specifically, the width variation of the flange 22 can be achieved in various ways; for example, the width of the flange 22 can increase linearly or according to a certain curved pattern. As a preferred embodiment, the width of the flange 22 increases linearly from the outer edge 24 to the inner edge 25 of the blade to ensure a more uniform distribution of airflow on the blade 2. In addition, the width variation of the flange 22 can also be achieved by adjusting the thickness of the flange 22 to further optimize the airflow distribution. By adjusting the width of the flange 22 to gradually increase from the outer edge 24 to the inner edge 25 of the blade, the airflow distribution on the blade 2 can be optimized. This design makes the flange 22 of the blade 2 adopt a progressive structure, with the flange 22 narrower near the blade tip and wider near the blade root, and the center of gravity closer to the impeller hub rotation center, resulting in more stable operation, better strength, and a more reasonable distribution of dynamic balance. Therefore, this design helps reduce uneven airflow distribution on blade 2, improving the efficiency and stability of the blade. By gradually increasing the width of the flange 22, the direction and speed of the airflow can be better controlled, reducing noise and vibration caused by uneven airflow and improving overall performance. Compared with existing technologies, the technical solution of this application has significant advantages in solving the technical problem of uneven airflow distribution caused by uneven flange 22 width.

[0029] Furthermore, serrations 26 are provided on the trailing edge of blade 2. The serration structure 26 can be implemented in various ways; for example, the shape of the serrations 26 can be triangular, trapezoidal, or other geometric shapes, and the size and spacing of the serrations 26 can be adjusted according to specific airflow conditions and the size of blade 2. Specifically, the height and width of the serrations 26 can be designed to be uniformly distributed or gradually distributed to adapt to different airflow separation requirements. As a preferred embodiment, the edges of the serrations 26 can be designed with a smooth transition to reduce local pressure concentration when airflow passes through. By setting the serration structure 26, the airflow separation at the trailing edge of blade 2 is more stable, reducing airflow impact and eddy current generation, thereby effectively reducing noise and vibration. The design of the serration structure 26 can disperse airflow, reduce local pressure concentration, further improve the aerodynamic performance of blade 2, and enhance the operational stability and efficiency of the axial flow fan. Compared with the prior art, this technical solution significantly improves the aerodynamic performance of blade 2 through simple structural improvements and solves the technical problem of noise and vibration generated by airflow impact at the trailing edge of blade 2 during operation.

[0030] In the specific design, the central hub support 1 is constructed as a metal hub support, with a bushing 11 formed at the center of the central hub support 1. The central hub support 1 also includes multiple connecting arms 12 arranged circumferentially on the outer side of the central hub support 1, with the blades 2 connected to the outer ends of the connecting arms 12. Specifically, the metal hub support can be made of aluminum alloy, stainless steel, or other high-strength metal materials to ensure its stability and durability during high-intensity operation. The bushing 11, formed at the center of the central hub support 1, can be achieved through casting, forging, or machining to ensure precise fit with the rotating shaft. The number of connecting arms 12 can be adjusted according to the specific requirements of the blades 2, typically from 3 to 6. The outer ends of the connecting arms 12 can be fixed to the blades 2 through welding, riveting, or bolting to ensure a strong connection. Thus, this technical solution, by adopting the design of the metal hub support and connecting arms 12, significantly improves the overall strength and rigidity of the axial flow fan blades and reduces the risk of vibration and deformation of the blades 2 during high-intensity operation. The use of metallic materials allows the hub bracket to better cope with airflow resistance, extending the service life of the axial flow fan blades. Furthermore, the circumferential arrangement of the connecting arm 12 makes the connection between the blade 2 and the hub bracket more stable, further improving the operating efficiency and stability of the fan blades. Compared with existing technologies, this solution has significant advantages in structural strength and operational stability, effectively solving the problem of blade 2's tendency to deform under high-intensity operation.

[0031] Furthermore, the outer end of the connecting arm 12 is bonded and fixed to the back pressure surface 23 of the blade 2. Specifically, the outer end of the connecting arm 12 can be directly bonded and fixed to the back pressure surface 23 of the blade 2 by means of bonding, welding, or mechanical fixation. As a preferred embodiment, the outer end of the connecting arm 12 and the back pressure surface 23 of the blade 2 can be bonded together with a high-strength adhesive to ensure a firm connection between the two. In addition, the outer end of the connecting arm 12 can also be fixed to the back pressure surface 23 of the blade 2 by welding, such as spot welding, laser welding, or other suitable welding methods. Mechanical fixation methods include using bolts, rivets, or other fasteners to fix the outer end of the connecting arm 12 to the back pressure surface 23 of the blade 2. Through this direct bonding and fixing method, the connection strength between the connecting arm 12 and the blade 2 is significantly enhanced, avoiding the problem of loosening or falling off the connection due to airflow resistance during high-intensity operation. Specifically, the outer end of the connecting arm 12 is directly bonded and fixed to the back pressure surface 23 of the blade 2, reducing the interference of the connection structure on the airflow of the blade 2 and ensuring a stable connection between the blade 2 and the connecting arm 12. This effectively improves the overall structural strength and operational stability of the axial flow fan, solving the technical problem of insecure fixing between the outer end of the connecting arm 12 and the back pressure surface 23 of the blade 2. Compared with existing technologies, this solution simplifies the connection structure through direct bonding and improves the reliability and durability of the connection, thus exhibiting better performance during the high-intensity operation of the axial flow fan.

[0032] In the specific design, through holes are provided on the outer end of the connecting arm 12 and the corresponding location on the blade 2. The through holes on the connecting arm 12 are aligned with the through holes on the blade 2 and then riveted together. The through holes can be circular, elliptical, or other shapes suitable for riveting, and their diameter and number can be adjusted according to actual needs. Riveting can be done using traditional rivets or other types of riveting methods, such as blind riveting or pull riveting. As a preferred embodiment, high-strength metal materials can be selected for riveting to ensure the strength and durability of the connection. By aligning the through holes on the connecting arm 12 with those on the blade 2 and then riveting them together, a stronger connection between the connecting arm 12 and the blade 2 is ensured. This fixing method not only improves the stability of the structure but also enhances the bending resistance of the blade 2 during high-intensity operation, thus preventing the blade 2 from collapsing and deforming due to airflow resistance. Through riveting, the connection between the connecting arm 12 and the blade 2 is tighter, reducing noise and vibration that may occur during operation and further improving the overall performance of the axial flow fan. Therefore, the technical solution of this application effectively solves the technical problem of the unstable fixing between the connecting arm 12 and the blade 2, and provides a more reliable and efficient connection method.

[0033] Example 2:

[0034] This embodiment provides an axial flow fan, which includes an axial flow blade with a folded edge 22. This axial flow blade adopts the design described in Embodiment 1. This technical solution solves the problem of blade 2's easy deformation under high-intensity operation by applying the axial flow blade with the folded edge 22 to the axial flow fan. The folded edge 22 structure enhances the bending resistance of the blade 2, reduces blade 2 deformation, thereby improving the fan's operating efficiency and stability. Simultaneously, the width variation of the folded edge 22 and the serration design 26 further optimize airflow, reduce noise, and improve the overall performance of the fan. Compared with the prior art, this technical solution has significant advantages in blade 2 bending resistance and noise control, effectively improving the service life and operating effect of the axial flow fan.

[0035] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0036] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. An axial flow fan blade with folded blade edges, comprising a central hub support (1) and a plurality of blades (2); the central hub support (1) includes a bushing (11) for connecting a rotating shaft, and the plurality of blades (2) are regularly connected to the central hub support (1) circumferentially; characterized in that: The blade (2) has a folded edge (22) formed by bending the leading edge (21) of the blade backward along its edge. The folded edge (22) is attached and fixed to the back pressure surface (23) of the leading edge (21) of the blade.

2. An axial flow fan blade with folded blade edges according to claim 1, characterized in that: The width of the folded edge (22) gradually increases from the outer edge (24) of the blade to the inner edge (25) of the blade.

3. An axial flow fan blade with folded blade edges according to claim 1, characterized in that: The trailing edge of the blade (2) is provided with serrations (26).

4. An axial flow fan blade with folded blade edges according to claim 1, characterized in that: The central hub bracket (1) is constructed as a metal hub bracket, and the bushing (11) is formed at the center of the central hub bracket (1); the central hub bracket (1) also includes a plurality of connecting arms (12) arranged circumferentially on the outside of the central hub bracket (1), and the blade (2) is connected to the outer end of the connecting arm (12).

5. An axial flow fan blade with folded blade edges according to claim 4, characterized in that: The outer end of the connecting arm (12) is attached and fixed to the back pressure surface (23) of the blade (2).

6. An axial flow fan blade with folded blade edges according to claim 4, characterized in that: Through holes are provided on the outer end of the connecting arm (12) and at the corresponding position on the blade (2). The through holes on the connecting arm (12) are aligned with the through holes on the blade (2) and then riveted together.

7. An axial flow fan, characterized in that: The axial flow fan blade with blade folds as described in any one of claims 1 to 6.

Images