Axial flow fan and air conditioner outdoor unit

Abstract

The utility model relates to the technical field of air conditioners, in particular to an axial flow fan and an air conditioner outdoor unit, and the axial flow fan comprises a mounting disc, blades and a first reinforcing part; the blades are arranged on the peripheral wall of the mounting disc; the first reinforcing parts are arranged on the pressure face of the blade and close to the front edge side of the blade, the multiple first reinforcing parts are distributed in the circumferential direction of the blade, and circumferential gaps are formed between the adjacent first reinforcing parts. The structural strength of the blades is improved, and therefore the strength requirement of the axial flow fan is met.

Description

Technical Field

[0001] This utility model relates to the field of air conditioning technology, and more specifically, to an axial flow fan and an outdoor unit for air conditioning. Background Technology

[0002] Currently, the fans in air conditioner outdoor units are usually axial fans, and most axial fans are made of plastic injection molding in one piece.

[0003] With the continuous development of air conditioning technology, axial fans are also gradually moving towards lightweight design, such as removing the bushings on the hub and reducing the thickness of the blades. However, the lightweight design of axial fans will reduce their structural strength, making them more susceptible to damage and affecting their performance in actual use. At the same time, during the injection molding process, it is easy to produce excessively thick local injection molding, resulting in large injection deformation, which does not meet the production requirements of axial fans. Utility Model Content

[0004] This utility model solves, to at least a certain extent, one of the technical problems in the related art.

[0005] Therefore, this application aims to provide an axial flow fan and an outdoor air conditioning unit, which, while removing the bushing at the shaft center of the mounting plate, provides a first reinforcing part between the blade pressure surface and the outer peripheral wall of the mounting plate to enhance the blade strength without the bushing, and at the same time solves the problem of stress concentration at the connection between the blade root and the mounting plate.

[0006] This application provides a recessed molding on the suction surface of the blade corresponding to the first reinforcing part, which improves the stress concentration problem at the connection between the blade root and the mounting plate and the stability of the fan injection molding.

[0007] To achieve the above objectives, this utility model provides an axial flow fan, comprising:

[0008] Installation disk;

[0009] Blades, which are located on the outer peripheral wall of the mounting plate;

[0010] The first reinforcing part is disposed on the pressure surface of the blade and close to the leading edge of the blade. The starting end of the first reinforcing part is disposed at the junction of the blade root and the outer peripheral wall of the mounting disk, and extends radially along the blade. Multiple first reinforcing parts are provided, and the multiple first reinforcing parts are distributed along the circumferential direction of the blade, and there is a circumferential gap between adjacent first reinforcing parts.

[0011] In this technical solution, to address the stress concentration issue at the connection between the blade root and the mounting plate in a bushing-less design, a first reinforcing section is installed in the high-stress zone at the leading edge root. This directly enhances the bending stiffness of the connection area, avoiding the risk of root fracture due to the absence of a bushing. Simultaneously, the first reinforcing section radially covers the blade root to the middle region, forming a continuous stress transmission path, dispersing centrifugal force and aerodynamic loads, and suppressing crack initiation. Multiple first reinforcing sections are arranged circumferentially along the blade, with circumferential gaps between adjacent sections, reducing material usage and avoiding injection molding shrinkage deformation caused by excessive local thickness.

[0012] In some embodiments of this application, the first reinforcing part is an arc-shaped reinforcing part, with the center of its arc curvature facing the leading edge of the blade, and the radius of curvature of the first reinforcing part is set to be between 1 / 10 and 1 / 20 of the blade diameter.

[0013] In the technical solution, the first reinforcing part is set as an arc-shaped reinforcing part, and the center of the arc curvature faces the leading edge of the blade, so that the windward side of the first reinforcing part forms a guide surface, which guides the airflow to smoothly transition along the pressure surface and reduces the leading edge separation vortex; a specific ratio of curvature radius balances the centrifugal force load and material distribution, further improving the blade strength.

[0014] In some embodiments of this application, the height of the first reinforcing part gradually decreases from the starting end to the ending end of the first reinforcing part; the height of the starting end of the first reinforcing part is set to be between 0.5% and 1.5% of the blade diameter.

[0015] In the technical solution, the height of the first reinforcing section decreases from the blade root to the blade root 234, so that the mass distribution of the reinforcing section is consistent with the attenuation trend of the centrifugal force of the blade, reducing the rotational inertial torque. At the same time, the gradient height disrupts the periodicity of the blade's natural frequency, effectively suppressing the resonance amplitude.

[0016] In some embodiments of this application, the width of the first reinforcing part is set to be between 2mm and 4mm.

[0017] In the technical solution, limiting the width range of the first reinforcing part can effectively avoid injection molding shrinkage marks. If the width of the first reinforcing part is too small, it will easily lead to insufficient filling. If the width of the first reinforcing part is too large, it will cause airflow disturbance.

[0018] In some embodiments of this application, the circumferential gap between adjacent first reinforcing parts is set to be between 2mm and 3mm.

[0019] In the technical solution, limiting the circumferential gap range between adjacent first reinforcing parts can effectively optimize the flowability of the injection molding melt during the injection molding process. If the circumferential gap is too small, it is easy to form weld lines, and if the circumferential gap is too large, it is easy to weaken the structural continuity.

[0020] In some embodiments of this application, the suction surface of the blade is provided with a recessed molding, and the recessed molding corresponds to the positions of a plurality of first reinforcing parts.

[0021] In the technical solution, a concave molding is provided on the suction surface of the blade corresponding to the first reinforcing part. The concave molding of the suction surface releases compressive stress by locally thinning the material, which is conducive to forming a symmetrical stress neutralization structure, extending the fatigue life of the blade root, and improving the injection molding stability during the production process.

[0022] In some embodiments of this application, the opening edge of the recessed molding is the first edge near the leading edge of the blade, and the opposite edge to the first edge is the second edge. The opening width of the recessed molding is the vertical projection distance between the first edge and the second edge in the chord length direction of the blade, and the opening width of the recessed molding gradually decreases from the root of the blade to the tip of the blade.

[0023] In the technical solution, by designing a gradient change in the opening width of the concave molding, it matches the load distribution of the first reinforcing part set on the suction surface of the blade. The increase in width near the blade root side enhances the bending stiffness of the starting end of the first reinforcing part, while the contraction of width at the end away from the blade root side avoids local mass redundancy and achieves a balance between lightweight and strength.

[0024] In some embodiments of this application, the lines connecting the leading edge of the blade root and the leading edge of the blade tip to the axis of the mounting disk form an angle Φ, and the lines connecting the two endpoints of the first edge to the axis of the mounting disk form an angle ω, wherein ω satisfies:

[0025]

[0026] Where D is the blade diameter.

[0027] In the technical solution, the geometric features of the concave profile are dynamically adapted to the blade size through the linear correlation between ω, Φ and D. This allows the stress release path of the concave profile to match the blade's spanwise bending deformation trend, thus avoiding local stress concentration.

[0028] In some embodiments of this application, the edge of the recessed molding corresponding to the first edge in the depth direction is the third edge, and the edge opposite to the third edge is the fourth edge. The bottom width of the recessed molding is the vertical projection distance between the third edge and the fourth edge in the blade chord direction. The opening width of the recessed molding is greater than the bottom width of the recessed molding and is in a preset ratio.

[0029] In the technical solution, by increasing the cross-sectional area of ​​the recessed molding opening, the uniformity of melt flow during injection molding can be improved, thereby enhancing injection molding stability; at the same time, the shrinking pit bottom structure can increase local stiffness.

[0030] In addition, this application also provides an outdoor unit for an air conditioner, comprising:

[0031] The housing includes the housing air inlet and the housing air outlet;

[0032] The heat exchanger is located inside the casing, near the air inlet of the casing.

[0033] The compressor is located inside the casing;

[0034] The fan, located inside the casing, is situated on the leeward side of the heat exchanger and near the air outlet of the casing. The fan includes:

[0035] Electric motor;

[0036] As mentioned above, the axial fan has a mounting plate connected to the motor, and the motor output shaft passes through the center of the mounting plate.

[0037] In the above embodiments, an axial flow fan and an outdoor air conditioning unit improve the fan structure by setting multiple circumferentially spaced first reinforcing parts on the blade pressure surface and setting gradient-changing concave profiles on the corresponding positions on the suction surface, achieving synergistic optimization of aerodynamic performance and structural strength. The first reinforcing parts are distributed at a uniform angle on the blade pressure surface, and their cross-sectional shape gradually narrows from the blade root to the blade tip, forming a progressive support structure that effectively disperses the centrifugal load during rotation. The concave profiles on the suction surface change gradient along the spanwise direction, and the opening width gradually expands from the blade root to the blade tip, forming a continuous acceleration flow channel that suppresses boundary layer separation and reduces flow losses. Through the alignment design of the pressure surface and the suction surface, the blade's resistance to deformation is enhanced, and the airflow distribution characteristics are optimized. While reducing noise, the fan's structural strength and operational stability are significantly improved, thus achieving a balance between lightweight and high reliability, and effectively improving injection molding stability. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of an outdoor air conditioning unit according to an embodiment of this application;

[0039] Figure 2 This is a schematic diagram of the overall structure of an outdoor air conditioning unit according to an embodiment of this application;

[0040] Figure 3 This is a schematic diagram of the overall structure of the concealed front panel of the outdoor unit of an air conditioner according to an embodiment of this application;

[0041] Figure 4 This is a schematic diagram of the pressure surface structure of a fan blade according to an embodiment of this application;

[0042] Figure 5 This is a schematic diagram of the suction surface structure of a fan blade according to an embodiment of this application;

[0043] Figure 6This is a schematic diagram of the first reinforcing part according to an embodiment of this application;

[0044] Figure 7 This is a schematic diagram of the structure of the first reinforcing part and the second reinforcing part according to the embodiments of this application;

[0045] Figure 8 This is a schematic diagram of blade wind speed zone division according to an embodiment of this application;

[0046] Figure 9 This is a schematic diagram of the structure of the first sub-reinforcing part according to an embodiment of this application;

[0047] Figure 10 This is a schematic diagram of a fan structure according to an embodiment of this application;

[0048] Figure 11 yes Figure 10 Enlarged view of a portion of point A in the middle;

[0049] Figure 12 This is a schematic diagram of a fan structure according to an embodiment of this application;

[0050] Figure 13 yes Figure 12 Enlarged view of a section at point B in the middle;

[0051] Figure 14 This is a front view of a fan structure according to an embodiment of this application.

[0052] Figure 15 This is a partial structural cross-sectional view of the fan according to an embodiment of this application;

[0053] Figure 16 This is a schematic diagram of a fan structure according to an embodiment of this application;

[0054] Figure 17 This is a schematic diagram of a fan structure according to an embodiment of this application;

[0055] Figure 18 This is a partial planar structural diagram of a fan according to an embodiment of this application;

[0056] Figure 19 This is a partial planar structural diagram of a fan according to an embodiment of this application;

[0057] Figure 20 yes Figure 17 Enlarged view of a section at point C;

[0058] Figure 21 This is a cross-sectional view of the fan according to an embodiment of this application;

[0059] Figure 22 yes Figure 21 A magnified view of a portion of point D in the middle.

[0060] In the above figures:

[0061] 100. Casing; 200. Fan; 300. Heat exchanger; 400. Compressor;

[0062] 101. Air inlet; 102. Air outlet;

[0063] 110. Top plate; 120. Front side plate; 130. Bottom plate;

[0064] 201. Motor; 202. Fan;

[0065] 210. Mounting plate; 230. Blade; 231. Leading edge; 232. Trailing edge; 233. Blade root; 234. Blade tip;

[0066] 310. First Reinforcement Section; 320. Second Reinforcement Section;

[0067] 330. Third Reinforcing Section; 331. First Sub-Reinforcing Section; 332. Second Sub-Reinforcing Section;

[0068] 24. First reinforcement section;

[0069] 27. Second reinforced part; 271. First edge; 272. Second edge; 273. Third edge; 274. Fourth edge;

[0070] 203. First plane; 204. Second plane; 205. Third plane; 206. Fourth plane; 207. Fifth plane;

[0071] 220. Sleeve; 240. First reinforcing member; 250. Second reinforcing member; 260. Third reinforcing member; 270. First mating part; 280. Gasket; 290. Second mating part;

[0072] 251. First connecting plate; 252. Second connecting plate; 253. Third connecting plate;

[0073] 261. First fixing ring; 262. Second fixing ring; 263. Reinforcing plate. Detailed Implementation

[0074] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0075] In the description of this application, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "level," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used 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. 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0076] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0077] As attached Figures 1 to 3 As shown, in an illustrative embodiment of the outdoor unit of the air conditioner of this utility model, the outdoor unit includes a housing 100, which forms the overall appearance of the outdoor unit; the top and bottom of the housing 100 are opposite ends, and the height direction of the housing 100 is from the top to the bottom; the left and right sides of the housing 100 are opposite sides, and the length direction of the housing 100 is from the left to the right; the front and rear sides of the housing 100 are opposite sides, and the thickness direction of the housing 100 is from the front to the rear.

[0078] The housing 100 includes a top plate 110, which is located at the top of the housing 100 and forms the top surface of the housing 100.

[0079] The housing 100 includes a base plate 130, which is located at the bottom of the housing 100 and forms the bottom surface of the housing 100. The base plate 130 and the top plate 110 are arranged opposite each other along the height direction of the housing 100.

[0080] The housing 100 includes a front side panel 120, which is located on the front side of the housing 100 and forms the front side surface of the housing 100.

[0081] The housing 100 includes a rear side panel located at the rear of the housing 100, which forms the rear side surface of the housing 100. It should be noted that in some embodiments, the housing 100 may not include a rear side panel to increase the air intake volume of the outdoor unit of the air conditioner.

[0082] The housing 100 includes an air inlet 101, which is located on the outer periphery of the housing 100.

[0083] The housing 100 includes an air outlet 102, which is located on the front side of the housing 100.

[0084] like Figure 3 As shown, the outdoor unit of the air conditioner includes a compressor 400, which is located inside the casing 100 and connected to the base plate 130. The compressor 400 is used to drive the flow of refrigerant.

[0085] The outdoor unit of the air conditioner includes a heat exchanger 300, which is located inside the casing 100. The heat exchanger 300 is used to exchange heat with the air passing through it. The heat exchanger 300 is placed on the base plate 130. The windward side of the heat exchanger 300 faces the air inlet 101, and the leeward side of part of the heat exchanger 300 faces the air inlet side of the fan 200. The operation of the fan 200 accelerates the heat exchange between the air and the heat exchanger 300, thereby increasing the heat exchange effect of the heat exchanger 300.

[0086] like Figure 2 and Figure 3 As shown, the outdoor unit of the air conditioner includes a fan 200, which is located inside the casing 100 and on the leeward side of the heat exchanger 300. The air outlet side of the fan 200 faces the air outlet 102. By operating the fan 200, air from outside the casing 100 is introduced into the casing 100 through the air inlet 101, and air from inside the casing 100 is output to the outside of the casing 100 through the air outlet 102.

[0087] In this embodiment, the fan 200 is an axial flow fan, and the fan 200 includes a motor 201. The output shaft of the motor 201 is arranged along the thickness direction of the housing 100, that is, the rotation axis of the fan 200 is arranged along the thickness direction of the housing 100.

[0088] The fan 200 includes a fan 202, which is connected to the output shaft of a motor 201. The motor 201 provides power to make the fan 202 rotate.

[0089] In related technologies, a bushing is usually provided in the fan 202 to increase the structural strength of the connection between the fan 202 and the output shaft of the motor 201. This prevents the connection between the fan 202 and the output shaft of the motor 201 from collapsing and being damaged due to the weight of the fan 202 itself when it rotates, thus affecting the normal use of the fan 200. However, the bushing not only increases the overall weight of the fan 202, but also increases the difficulty of injection molding the fan 202 shaft, making it prone to problems during production and installation.

[0090] In some embodiments, such as Figure 3 and Figure 4 As shown, the fan 202 includes a mounting plate 210 for connecting the motor 201, and the output shaft of the motor 201 passes through the axis of the mounting plate 210.

[0091] The fan 202 includes blades 230, which are disposed on the outer peripheral wall of the mounting plate 210. There are multiple blades 230. In this embodiment, there are 3 blades 230. The 3 blades 230 are spaced around the outer peripheral wall of the mounting plate 210. There is a certain curvature at the connection between the blades 230 and the mounting plate 210, that is, the blades 230 rotate at a certain angle to facilitate the flow of outside air along the axis of the fan 202.

[0092] The blade 230 includes a leading edge 231, which is an edge on the blade 230 that extends outward from the outer peripheral wall of the mounting disk 210. The leading edge 231 is the edge on the forward side of the blade 230 in the direction of rotation.

[0093] The blade 230 includes a trailing edge 232, which is another edge on the blade 230 that extends outward from the outer peripheral wall of the mounting disk 210. The trailing edge 232 forms the opposite side edge of the blade 230 in the direction of rotation. In the direction of rotation, the leading edge 231 is located in front of the trailing edge 232, and the trailing edge 232 is located behind the leading edge 231.

[0094] The blade 230 includes a leaf tip 234, which is the outermost edge of the blade 230. The leaf tip 234 connects the outermost end of the leading edge 231 and the trailing edge 232.

[0095] The blade 230 includes a blade root 233, which is the edge where the blade 230 connects to the mounting plate 210.

[0096] The leading edge 231 and the trailing edge 232 are two edges on the blade 230 that extend outward from the outer peripheral wall of the mounting disk 210; the leading edge 231 forms the edge on the forward side of the blade 230 in the direction of rotation, and the trailing edge 232 forms the edge on the opposite side of the blade 230 in the direction of rotation. In the direction of rotation, the leading edge 231 is located ahead of the trailing edge 232, and the trailing edge 232 is located behind the leading edge 231.

[0097] In axial flow fans, the pressure surface of the blades is usually the front side of blade 230, that is, the side of blade 230 facing the air outlet of the outdoor unit of the air conditioner. On the pressure surface, the airflow velocity is lower and the static pressure is higher.

[0098] In axial flow fans, the suction surface of the blades is usually the back of the blade 230, that is, the side of the blade 230 that faces away from the air outlet of the outdoor unit of the air conditioner. On the suction surface, the airflow velocity is higher and the static pressure is lower.

[0099] In some embodiments, such as Figures 4-6 As shown, the fan 202 includes a first reinforcing part 310, which is disposed on the suction surface of the blades.

[0100] The first reinforcing part 310 is disposed near the leading edge 231 of the blade 230, and the first reinforcing part 310 extends from the root 233 of the blade 230 to the tip 234 of the blade 230.

[0101] The fan 202 includes a second reinforcing part 320, which is disposed on the suction surface of the blades.

[0102] The second reinforcing part 320 is disposed near the trailing edge 232 of the blade, and the second reinforcing part 320 extends from the root 233 of the blade 230 to the tip 234 of the blade 230.

[0103] The first reinforcing section 310 and the second reinforcing section 320 extend continuously along the span of the blade 230, forming a skeleton-like support structure that significantly improves the bending and torsional stiffness of the blade 230. The first reinforcing section 310 is located on the leading edge 231 side of the blade 230, which reduces leading edge separation vortices by smoothing the airflow attachment; the second reinforcing section 320 is located on the trailing edge 232 side of the blade 230 to suppress wake vortex shedding and reduce wake turbulent kinetic energy. This reduces vibration and deformation during operation, effectively suppresses airflow separation, reduces noise and improves efficiency, while reducing stress concentration and the risk of fatigue fracture.

[0104] In some embodiments, the widths of the first reinforcing portion 310 and the second reinforcing portion 320 increase linearly with the increase of the radial distance from the axis of the mounting plate 210.

[0105] In this embodiment, as Figure 6As shown, taking the width variation law of the first reinforcing part 310 as an example, the linear relationship between the width of the first reinforcing part 310 and the radial distance from the axis of the mounting plate 210 is as follows:

[0106] H = 0.2506 × R + 11.5 mm

[0107] Wherein, H is the width of the first reinforcing part 310, and R is the radial distance from the axis of the mounting plate 210.

[0108] like Figure 6 As shown, if the width of the first reinforcing strip near the blade root 233 is defined as H1, and the width near the blade tip 234 is defined as H2, then H1 < H2. Since the blade tip 234 of the blade 230 will bear greater centrifugal force and aerodynamic load than the blade root 233 side when the axial fan is running, the blade tip 234 side needs a wider reinforcing section to provide support. The wider reinforcing section significantly enhances the support strength of this area, suppresses the risk of local deformation or fracture caused by stress concentration, and at the same time, the width reduction of the blade root 233 side avoids the accumulation of redundant material. Under the premise of ensuring structural stability, lightweight design is achieved, the mass distribution of the blade 230 is optimized to reduce energy consumption, and the flow field disturbance caused by the sudden change in thickness is reduced, thereby comprehensively improving the fatigue resistance, aerodynamic efficiency and operational reliability of the blade 230.

[0109] In some embodiments, the thickness of the first reinforcing portion 310 and the second reinforcing portion 320 decreases linearly with the increase of the radial distance from the axis of the mounting plate 210.

[0110] In this embodiment, taking the thickness variation law of the first reinforcing part 310 as an example, the linear relationship between the width of the first reinforcing part 310 and the radial distance from the axis of the mounting plate 210 is as follows:

[0111] B = -0.0096 × R + 3.8 mm

[0112] Wherein, B is the width of the first reinforcing part 310, and R is the radial distance from the axis of the mounting plate 210.

[0113] If the thickness of the first reinforcing strip near the blade root 233 is defined as B1, and the width near the blade tip 234 is defined as B2, then B1 > B2. Since the blade tip 234 rotates at high speeds during axial fan operation, its thickness needs to be reduced to decrease centrifugal force. Conversely, the blade root 233 of the blade experiences higher stress, requiring increased thickness to enhance bending resistance. By increasing the thickness of the first reinforcing strip near the blade root 233 and increasing its width at the blade tip 234, a better match between the dynamic load and structural strength of the blade 230 is achieved: reducing the thickness at the blade tip 234 mitigates the centrifugal force generated by high-speed rotation, reducing vibration and fatigue damage caused by uneven mass distribution; increasing the thickness at the blade root 233 significantly improves bending resistance and suppresses the risk of microcrack propagation caused by stress concentration. Simultaneously, the overall blade 230 optimizes its aerodynamic shape through a gradual transition in thickness and width, reducing flow separation and turbulence disturbance, thereby enhancing structural stability while reducing operating noise.

[0114] In some embodiments, the first reinforcing portion 310 and the leading edge 231 of the blade 230 have a first gap, and the first gap is constant.

[0115] In this embodiment, the first gap S1 is constant, and the first gap S1 can be set as follows: S1≥20mm and S1≤40mm.

[0116] In some embodiments, when S1≥20mm, the width of the first gap is sufficient to suppress the formation of a local backflow zone between the reinforcing part and the blade by the leading edge airflow, reduce broadband noise caused by airflow pulsation, and reduce the possibility of insufficient melt filling due to the gap being too small, thus ensuring the stability of the injection molding process; when S1≤40mm, the width of the first gap is adapted to the gradient distribution law of the centrifugal force when the blade rotates, so that the dynamic stress borne by the blade root region decreases, and the geometric continuity between the gap edge and the leading edge of the blade suppresses the initiation and propagation of fatigue cracks.

[0117] In some embodiments, when S1 = 20 mm, it can effectively suppress the leading edge airflow disturbance while ensuring the structural support strength of the blade root region, which is suitable for small blades; when S1 = 40 mm, it can reduce flow resistance under high-speed conditions and adapt to the centrifugal force distribution requirements of large blades; for medium-sized blades, when S1 = 30 mm, it can balance the drag reduction effect and structural reliability.

[0118] By setting a constant first gap between the first reinforcing part 310 and the leading edge 231 of the blade 230, the formation of a local backflow zone between the leading edge airflow can be prevented, reducing broadband noise caused by airflow pulsation; on the other hand, the constant gap simplifies mold design and improves the stability of the injection molding process.

[0119] In some embodiments, such as Figure 7As shown, a second gap is formed between the first reinforcing part 310 and the second reinforcing part 320, and the width of the second gap increases linearly with the increase of the radial distance from the axis of the mounting plate 210.

[0120] In this embodiment, as Figure 7 As shown, the width of the second gap is defined by the two intersection points of the chord length line of any radial position of the blade 230 with the trailing edge of the first reinforcing part 310 and the leading edge of the second reinforcing part 320. The chord length refers to the straight-line distance from the leading edge 231 to the trailing edge 232 of the blade 230 at any radial position.

[0121] by Figure 7 Taking the chord line L1 at the indicated position as an example, the intersection point of L1 and the rear edge of the first reinforcing part 310 is P1, the intersection point of L1 and the front edge of the second reinforcing part 320 is P2, and the width of the second gap is the straight-line distance between the intersection point P1 and the intersection point P2 in the chord direction.

[0122] by Figure 7 Taking the chord length line L2 at the indicated position as an example, the intersection point of L2 and the rear edge of the first reinforcing part 310 is P3, the intersection point of L1 and the front edge of the second reinforcing part 320 is P4, and the width of the second gap is the straight-line distance between the intersection point P3 and the intersection point P4 in the chord length direction.

[0123] The aforementioned intersection points form a constant angle with the lines connecting them to the axis of mounting plate 210; at any radial position of the fan, i.e., at any radial distance from the axis of mounting plate 210, the angle f remains unchanged. Figure 7 Taking the positions shown in the diagram as an example, the lines connecting intersection point P1 and intersection point P2 to the axis of mounting plate 210 form an angle f1, and the lines connecting intersection point P3 and intersection point P4 to the axis of mounting plate 210 form an angle f2, where f1 = f2.

[0124] In this embodiment, the included angle f satisfies: 40°≤f≤60°.

[0125] The linearly increasing gap width is adapted to the drag reduction requirements of the high-speed region on the tip 234 side of blade 230, reducing flow losses and lowering local turbulence intensity; the geometric constraint of constant included angle ensures the directional guidance of the gap on the airflow, suppresses circumferential flow separation and weakens vortex shedding energy, while the included angle range balances the structural support strength and the expansion efficiency of the airflow channel, avoiding stress concentration or flow disturbance caused by excessively large or small angles. Ultimately, while improving the fan's operating efficiency and quietness, it ensures the deformation resistance and long-term reliability of blade 230 under dynamic loads.

[0126] In some embodiments, such as Figures 8-9 As shown, the fan 202 includes a third reinforcing part 330, which is configured according to the wind speed range.

[0127] In this embodiment, the wind speed zone is divided based on the outer diameter R of the mounting plate 210. h Using this as the starting point, the blade is radially divided into three annular regions: a low-speed region, a high-speed region, and a low-speed zone. The outer diameter R of the mounting plate 210 is used as the reference point. h Starting from the radius at the tip of the blade and ending at the radius, the radial range of each region extends outward in a ratio of 3:4:3.

[0128] Wind speed zones include low-speed zones, and low-speed zones (R) h <R≤R 低速 The radial range of ) accounts for 3 / 10 of the total design area.

[0129] The wind speed area includes the medium speed area, the medium speed area (R 低速 <R≤R 高速 The radial range of ) accounts for 4 / 10 of the total design area.

[0130] Wind speed zones include high-speed zones, where R > R. 高速 The radial range of ) accounts for 3 / 10 of the total design area.

[0131] like Figure 8 As shown, in some embodiments, the third reinforcing part 330 includes a first sub-reinforcing part 331, which is disposed in the low-speed region of the blade. The radial range of the low-speed region of the blade is from the outer diameter of the mounting disk 210 to the preset low-speed radius. A plurality of first sub-reinforcing parts 331 are distributed in concentric circles with equal radial spacing around the axis of the mounting disk 210, and are distributed at equal angular intervals along the circumferential direction on the same circumference.

[0132] In some embodiments, the first sub-reinforcing portion 331 is configured as an arc-shaped strip protrusion.

[0133] In this embodiment, the circumferential radius R1 corresponding to the starting position of the first sub-reinforcing part 331 is:

[0134] R1 = 1.05 × R h

[0135] That is, the first sub-reinforcing part 331 starts at a radial position 5% of the outer diameter of the mounting plate 210.

[0136] like Figure 9 As shown, the radial distribution pattern of the first sub-reinforcing part 331 is set as follows: the radial spacing c between adjacent concentric circles is:

[0137] c = 0.05 × R h

[0138] That is, forming concentric circles with equal radial spacing;

[0139] The radial distribution pattern of the first sub-reinforcing part 331 is set as follows:

[0140] The starting point and ending point of the first sub-reinforcement 331 are respectively connected to the axis of the mounting plate 210 to form a width angle α, which satisfies: α ≥ 8° and α ≤ 10°.

[0141] In some embodiments, when a ≥ 8°, the circumferential coverage angle of the first sub-reinforcement 331 can cover the key separation point in the low-speed region, enhancing laminar flow adhesion and reducing near-wall frictional resistance; when a ≤ 10°, the circumferential coverage angle of the first sub-reinforcement 331 limits the circumferential extension length of the protrusion, preventing airflow channel blockage and maintaining flow stability.

[0142] In some embodiments, when a = 9°, frictional resistance and pressure loss are synergistically optimized, and the uniformity of injection filling is improved.

[0143] The circumferential spacing angle between adjacent first sub-reinforcing parts 331 is b = a + 2°, ensuring that the spacing angle is always greater than the width angle of 2°.

[0144] The radial spacing design of the first sub-reinforcing section 331 optimizes the mass distribution, reduces rotational inertia torque, lowers vibration risk, and reduces local stress concentration, thereby improving fatigue life. On the other hand, the width angle and spacing angle of the first sub-reinforcing section 331 are coupled to control the balance between the structural coverage and the unobstructed flow channel, reducing the possibility of airflow blockage and achieving drag reduction and noise reduction.

[0145] like Figure 8 As shown, in some embodiments, the third reinforcing part 330 includes a second sub-reinforcing part 332, which is disposed in the low-speed region of the blade. The radial range of the medium-speed region of the blade is from a preset low-speed radius to a preset high-speed radius. A plurality of second sub-reinforcing parts 332 are distributed in concentric circles with equal radial spacing around the axis of the mounting disk 210, and are distributed at equal angular intervals along the circumferential direction on the same circumference.

[0146] The second sub-reinforcing part 332 is a polygonal dot-shaped protrusion. The side length of the polygonal dot-shaped protrusion decreases linearly with the increase of the radial distance from the axis of the mounting plate 210.

[0147] In this embodiment, the second sub-reinforcing part 332 is a polygonal dot-shaped protrusion with a side length of n. n can be set to any regular polygon greater than or equal to 6. Taking a regular hexagon as an example, the linear relationship between its side length l and the radial distance from the axis of the mounting plate 210 is set as follows:

[0148] l = -0.0181 × R + 5.6 mm

[0149] The polygonal dot-shaped protrusions in the second sub-reinforcement section 332 achieve synergistic optimization of aerodynamic performance and structural strength in the mid-speed region of the blade. The side length of the polygonal dot-shaped protrusions decreases linearly with the radial distance from the axis of the mounting plate 210, which reduces high-speed airflow disturbance and flow resistance on the blade tip 234 side near the blade 230. On the side away from the blade tip 234, polygonal dot-shaped protrusions with larger side lengths are used to enhance structural support strength and guide stable adhesion of low-speed airflow. On the other hand, the regular distribution of equal radial spacing and circumferential equal angles simplifies mold design and ensures the accuracy and consistency of injection molding.

[0150] In some embodiments, the high-speed region of the blade is set as a smooth surface, without additional reinforcement.

[0151] The axial flow fan provided in this application improves the fan structure by setting a first reinforcing part 310 and a second reinforcing part 320 on the suction surface of the blades, and setting a third reinforcing part 330 according to the wind speed region of the blades, thereby achieving synergistic optimization of structural strength and aerodynamic performance: the first reinforcing part 310 suppresses airflow separation, the second reinforcing part 320 weakens vortex shedding, effectively improving the lift coefficient and reducing high-frequency noise; the third reinforcing part 330 is divided into low-speed and medium-speed regions, specifically optimizing flow stability and turbulent mixing efficiency, reducing frictional resistance and achieving effective noise reduction.

[0152] In other embodiments, different structures than those described above can be used to improve the strength of the shaftless axial fan. The following is a detailed explanation... Figures 10-15 This embodiment will be described in detail.

[0153] In some embodiments, such as Figures 10-11 As shown, the fan 202 includes a first reinforcing part 24, which is disposed on the blade pressure surface and close to the leading edge 231 of the blade 230. The starting end of the first reinforcing part 24 is disposed at the junction of the blade root 233 of the blade 230 and the outer peripheral wall of the mounting plate 210 and extends radially along the blade 230. Multiple first reinforcing parts 24 are provided, and the multiple first reinforcing parts 24 are arranged circumferentially along the blade 230, and there is a circumferential gap between adjacent first reinforcing parts 24.

[0154] Because stress concentration is prone to occur at the connection between the blade root 233 and the mounting plate 210 in a bushingless axial fan, a first reinforcing part 24 is provided in the high-stress area at the root of the leading edge 231 to directly enhance the bending strength of the connection area and reduce the risk of root fracture due to the lack of bushing. At the same time, the first reinforcing part 24 covers the root to the middle area of ​​the blade 230 radially, forming a continuous stress transmission path, dispersing centrifugal force and aerodynamic load, and inhibiting crack initiation.

[0155] In this embodiment, the number of the plurality of first reinforcing parts 24 is set to 3, and the specific number can be adjusted according to the size of the blade 230 and the design requirements.

[0156] Three first reinforcing parts 24, evenly distributed along the circumference of the blade 230, form a triangular reinforcement zone, providing symmetrical support at the junction of the blade root 233 and the mounting plate 210. This ensures that centrifugal force is evenly distributed circumferentially, avoiding stress concentration on one side. Compared to a single reinforcing part design, the arrangement of three reinforcing parts significantly improves the bending stiffness of the blade root 233 region, while keeping the weight increase within a reasonable range, meeting lightweight design requirements.

[0157] In some embodiments, the first reinforcing part 24 is an arc-shaped reinforcing part, the center of its arc curvature is directed toward the leading edge 231 of the blade 230, and the radius of curvature of the first reinforcing part 24 is set to be between 1 / 10 of the blade diameter and 1 / 20 of the blade diameter.

[0158] The first reinforcing part 24 is configured as an arc-shaped reinforcing part, with the center of the arc curvature facing the leading edge 231 of the blade 230. This forms a guide surface on the windward side of the first reinforcing part 24, guiding the airflow smoothly along the pressure surface, reducing separation vortices at the leading edge 231, and thus reducing stress in the high-stress area of ​​the blade 230. Compared with triangular and zigzag reinforcing parts, the arc-shaped reinforcing part can better disperse stress and reduce stress concentration in the high-stress area of ​​the blade 230. The sharp angles of triangular and zigzag reinforcing parts may lead to stress concentration, reducing the strength enhancement effect of the blade 230. On the other hand, the smooth structure of the arc-shaped reinforcing part can reduce local stress in the mold and enhance the stability during the injection molding process.

[0159] The diameter of blade 230 refers to twice the straight-line distance from the outermost tip of blade 230 (the blade tip) to the axis of mounting plate 210, expressed as:

[0160] D = 2r

[0161] Where D is the diameter of blade 230, and r is the distance from the blade tip to the axis of mounting plate 210.

[0162] The radius of curvature is a geometric parameter that describes the degree of curvature of a curve or surface. The larger the radius of curvature, the smaller the degree of curvature of the curve or surface. The radius of curvature of the first reinforcing part 24 represents the degree of curvature of the first reinforcing part 24. It can be set to between 1 / 10 of the diameter of the blade 230 and 1 / 20 of the diameter of the blade 230, expressed as: R≥D / 20 and R≤D / 10.

[0163] Where D is the diameter of blade 230 and R is the radius of curvature of the first reinforcement part 24.

[0164] In some embodiments, when R≥D / 20, the radius of curvature of the first reinforcement 24 is adapted to the attenuation gradient of the blade centrifugal force, forming a continuous stress transmission path and suppressing stress abrupt changes in the blade root region; when R≤D / 10, the radius of curvature of the first reinforcement 24 enhances the leading edge airflow guiding effect, which can reduce the energy of the separation vortex and reduce flow loss.

[0165] In some embodiments, when R = 3D / 40, the dynamic stress distribution and aerodynamic performance are synergistically optimized, the blade root fatigue life is extended, and the uniformity of injection molding filling is improved.

[0166] In some embodiments, the radius of curvature of the first reinforcing part 24 affects its stress distribution under centrifugal force. The radius of curvature of the first reinforcing part 24 can be set to 1 / 15D to ensure that the curvature of the first reinforcing part 24 is consistent with the centrifugal force attenuation gradient when the blade 230 rotates, forming a continuous stress transmission path and avoiding stress abrupt changes.

[0167] In some embodiments, the height of the first reinforcement portion 24 gradually decreases from the starting end to the ending end of the first reinforcement portion 24; the height of the starting end of the first reinforcement portion 24 is set to be between 0.5% of the diameter of the blade 230 and 1.5% of the diameter of the blade 230.

[0168] Since the blade root 233 region is the area with the greatest stress when the axial fan rotates, the starting end of the first reinforcement part 24, that is, the position where it is located at the junction of the blade root 233 of the blade 230 and the outer peripheral wall of the mounting plate 210, is set to the highest height, thereby effectively enhancing the structural strength of the area with the greatest stress.

[0169] The first reinforcing section 24 extends from the starting end towards the blade tip 234, its height gradually decreasing until it reaches 0 mm. This decreasing height towards the blade tip 234 aligns with the radial attenuation trend of centrifugal force, reducing inertial loads caused by redundant material at the blade tip and minimizing rotational energy consumption. Simultaneously, the linear height reduction eliminates abrupt changes in cross-section, reducing stress concentration points and effectively extending the fatigue life of the blade 230. Furthermore, the gradient structure of the first reinforcing section 24 without right-angle transitions reduces localized stress in the mold, enhancing stability during the injection molding process.

[0170] The initial height of the first reinforcing part 24 is set to be between 0.5% and 1.5% of the blade diameter, expressed as: H0 ≥ 0.5%D and H0 ≤ 1.5%D. Wherein, H0 is the initial height of the first reinforcing part 24.

[0171] In some embodiments, when H0≥0.5%D, by increasing the height of the starting end, the bending stiffness of the blade root region is significantly enhanced, the maximum stress concentration factor of the blade root is reduced, and the centrifugal force attenuation gradient is matched to reduce rotational energy consumption; when H0≤1.5%D, by limiting the maximum height of the starting end, the possibility of redundant material accumulation at the blade root is reduced, achieving lightweight design, and the gradient transition structure eliminates abrupt changes in cross-section and suppresses the initiation of fatigue cracks.

[0172] In some embodiments, when H0 = 1.0%D, dynamic load adaptability can be better optimized, pneumatic efficiency can be improved, and injection molding process stability can be enhanced.

[0173] In some embodiments, the starting end height of the first reinforcement 24 can be set to 0.1%D. The starting height of 0.1%D forms a micro-reinforcement anchor point at the junction of the blade root 233, which specifically improves the bending stiffness and reduces the possibility of material redundancy in traditional large-size reinforcements.

[0174] In some embodiments, the width e of the first reinforcing part 24 is set to be between 2mm and 4mm, that is, the width e of the first reinforcing part 24 satisfies: e≥2mm and e≤4mm.

[0175] In some embodiments, when e≥2mm, increasing the width effectively reduces the possibility of insufficient filling of the injection melt, ensuring the structural integrity of the reinforced part, while suppressing cooling shrinkage caused by local thinning; when e≤4mm, limiting the maximum width reduces turbulent disturbance when airflow passes through, maintaining the flow stability of the suction surface to reduce broadband noise.

[0176] In some embodiments, when e = 3 mm, the synergistic optimization of injection molding process stability and aerodynamic performance can be better achieved. Limiting the width range of the first reinforcing part 24 can effectively reduce injection molding shrinkage marks. If the width of the first reinforcing part 24 is too small, it will easily lead to insufficient filling. If the width of the first reinforcing part 24 is too large, it will cause airflow disturbance.

[0177] In some embodiments, the circumferential gap d between adjacent first reinforcing parts 24 is set to be between 2mm and 3mm, that is, the circumferential gap d between adjacent first reinforcing parts 24 satisfies: d≥2mm and d≤3mm.

[0178] In some embodiments, when d≥2mm, the flowability of the injection molten metal is effectively optimized by increasing the circumferential gap between adjacent first reinforcing parts 24, while suppressing weld lines caused by excessively small circumferential gaps; when e≤4mm, the structural continuity and strength of the first reinforcing parts 24 are ensured by limiting the maximum value of the circumferential gap between adjacent first reinforcing parts 24.

[0179] In some embodiments, when d = 2.5 mm, synergistic optimization of injection molding process stability and structural strength can be achieved.

[0180] Limiting the circumferential gap range between adjacent first reinforcing parts 24 can effectively optimize the flowability of the injection molding melt during the injection molding process. If the circumferential gap is too small, weld lines are easily formed, while if the circumferential gap is too large, the structural continuity is easily weakened.

[0181] In some embodiments, such as Figures 12-13 As shown, the suction surface of the blade 230 is provided with a second reinforcement part 27 and the second reinforcement part 27 corresponds to the positions of a plurality of first reinforcement parts 24.

[0182] In this embodiment, the centerline position of the second reinforcing part 27 corresponds to the centerline position of the three first reinforcing parts 24 located in the middle. The second reinforcing part 27 is provided on the blade suction surface corresponding to the first reinforcing part 24. The second reinforcing part 27 on the suction surface releases compressive stress by locally thinning the material, which is beneficial to forming a symmetrical stress neutralization structure, extending the fatigue life of the blade root 233, and improving the injection molding stability during the production process.

[0183] In some embodiments, the opening edge of the second reinforcing part 27 near the leading edge 231 of the blade 230 is the first edge 271, and the opposite edge to the first edge 271 is the second edge 272. The opening width of the second reinforcing part 27 is the vertical projection distance between the first edge 271 and the second edge 272 in the chordal direction of the blade 230, and the opening width of the second reinforcing part 27 gradually decreases from the root 233 of the blade 230 towards the tip 234.

[0184] In this embodiment, the opening width of the second reinforcing part 27 gradually decreases from the leaf root 233 of the blade 230 towards the leaf tip 234. The opening width at the end closer to the leaf root 233 is h2, and the opening width at the end farther from the leaf root 233 is h1. The ratio between the two can be set as follows:

[0185] h2 = 1.5h1

[0186] The width of the opening at the end furthest from the leaf root 233 is h1, and h1 can be set as: h1≥1.5e and h1≤3e.

[0187] In some embodiments, when h1≥1.5e, a larger opening width can enhance the structural continuity of the blade root region, thereby suppressing injection molding cooling deformation and reducing the stress concentration factor; the opening width enhances the structural continuity of the blade root region, suppresses injection molding cooling deformation and reduces the stress concentration factor; when h1≤3e, by limiting the maximum value of the opening width, the expansion rate of the airflow channel can be effectively controlled, thereby maintaining the velocity gradient of the suction surface and suppressing boundary layer separation.

[0188] In some embodiments, when h1 = 2.25e, synergistic optimization of structural strength and aerodynamic performance can be achieved, extending the fatigue life of the blade root and improving the uniformity of injection molding filling.

[0189] The opening width of the second reinforcement part 27 gradually decreases from the blade root 233 to the blade tip 234, matching the load distribution of the first reinforcement part 24 located on the blade suction surface. The increase in width near the blade root 233 strengthens the bending stiffness of the starting end of the first reinforcement part 24, while the contraction of width away from the blade root 233 avoids local mass redundancy, achieving a balance between lightweight and strength.

[0190] On the other hand, the opening width gradually decreases from the blade root 233 to the blade tip 234, which can form a constricted flow channel, accelerate the airflow through the concave area, suppress the separation of the suction surface boundary layer, and reduce operating noise.

[0191] In some embodiments, such as Figure 14 As shown, the lines connecting the leading edge 231 of the blade root 233 and the leading edge 231 of the blade tip to the axis of the mounting disk 210 form an angle Φ, and the lines connecting the two endpoints of the first edge 271 to the axis of the mounting disk 210 form an angle ω, where ω satisfies:

[0192]

[0193] Where D is the blade diameter.

[0194] In some embodiments, the edge of the second reinforcing portion 27 corresponding to the first edge 271 in the depth direction is the third edge 273, and the edge opposite to the third edge 273 is the fourth edge 274. The bottom width of the second reinforcing portion is the vertical projection distance between the third edge 273 and the fourth edge 274 in the chordal direction of the blade 230. The opening width of the second reinforcing portion 27 is greater than the bottom width of the second reinforcing portion and is in a preset proportion. The opening width of the second reinforcing portion 27 is greater than the bottom width of the pit and is in a preset proportion.

[0195] In this embodiment, as Figure 15 As shown, the opening width of the second reinforcing part 27 is x2, and the bottom width of the second reinforcing part 27 is x1. The ratio between the two can be set as follows:

[0196] x2 = 2x1

[0197] In this embodiment, the centerline of the recessed molding corresponds to the location of the maximum thickness of the blade 230 cross-section, and the depth L of the second reinforcing part 27 is set as follows:

[0198] L = 2x1

[0199] The width of the concave molding gradually expands from the bottom of the concave area to the opening, forming a near-trapezoidal shape. This creates a gradually expanding flow channel, accelerating the airflow through the concave area. At the same time, the deep eddy generation effect disrupts the low-speed boundary layer, delays flow separation, dissipates turbulent kinetic energy, reduces broadband noise, and weakens the stress in the high-stress area of ​​the blade at 230°. Meanwhile, the contracted bottom structure can increase local stiffness.

[0200] On the other hand, by increasing the cross-sectional area of ​​the opening of the second reinforcing part 27, the uniformity of melt flow during injection molding can be improved, thereby enhancing injection molding stability.

[0201] The aforementioned axial fan achieves synergistic optimization of aerodynamic performance and structural strength by incorporating multiple circumferentially spaced first reinforcing sections 24 on the blade pressure surface and gradient-varying second reinforcing sections 27 on the corresponding suction surface. The first reinforcing sections 24 are evenly distributed on the blade pressure surface, with their cross-sectional shape gradually narrowing from the blade root 233 to the blade tip, forming a progressive support structure that effectively disperses centrifugal loads during rotation. The second reinforcing sections 27 on the suction surface exhibit a gradient along the spanwise direction, with the opening width gradually increasing from the blade root 233 to the blade root 234, forming a continuous acceleration channel that suppresses boundary layer separation and reduces flow losses. Through the alignment design of the pressure and suction surfaces, the deformation resistance of the blade 230 is enhanced, and the airflow distribution characteristics are optimized. This significantly improves the structural strength and operational stability of the fan 202 while reducing noise, thus achieving a balance between lightweight design and high reliability.

[0202] In other embodiments, different structures than those described above can be used to improve the strength of the shaftless axial fan. The following is a detailed explanation... Figures 16-20 This embodiment will be described in detail.

[0203] like Figure 16 As shown, the fan 202 includes a sleeve 220, which is axially arranged along the mounting plate 210, and the outer peripheral wall of the mounting plate 210 is connected to the inner wall of the sleeve 220.

[0204] like Figure 16 As shown, the fan 202 includes blades 230, which are disposed on the outer peripheral wall of the mounting plate 210. There are multiple blades 230. In this embodiment, there are 3 blades 230. The 3 blades 230 are spaced around the outer peripheral wall of the sleeve 220. There is a certain curvature at the connection between the blades 230 and the sleeve 220, that is, the blades 230 rotate at a certain angle to facilitate the flow of outside air along the axis of the fan 202.

[0205] The fan 202 includes a first reinforcing member 240, which is disposed on the side of the mounting plate 210 facing the motor 201. The first reinforcing member 240 is connected to the inner wall of the sleeve 220. The length direction of the first reinforcing member 240 is arranged along the radial direction of the mounting plate 210. Multiple first reinforcing members 240 are provided and arranged circumferentially along the mounting plate 210.

[0206] like Figure 17As shown, the fan 202 includes a second reinforcing member 250, which is disposed on the side of the mounting plate 210 away from the first reinforcing member 240. The second reinforcing member 250 is connected to the inner wall of the sleeve 220. The length direction of the second reinforcing member 250 is arranged along the radial direction of the mounting plate 210. Multiple second reinforcing members 250 are provided and arranged along the circumference of the mounting plate 210. The second reinforcing members 250 and the first reinforcing member 240 are staggered along the axial direction of the mounting plate 210.

[0207] In this embodiment, the number of first reinforcing members 240 is set to 3, and the included angle between the line connecting two adjacent first reinforcing members 240 and the axis of the mounting plate 210 is equal; the number of second reinforcing members 250 is set to 6, and the included angle between two adjacent second reinforcing members 250 and the axis of the mounting plate 210 is equal.

[0208] By providing a first reinforcing member 240 and a second reinforcing member 250 on both sides of the mounting plate 210, the structural strength of the mounting plate 210 can meet the strength requirements of the axial fan even without a bushing. Simultaneously, the inclusion of the first reinforcing member 240 and the second reinforcing member 250 prevents the fan 202 from easily denting during injection molding due to difficulty in controlling the intermediate thickness after the bushing is removed, thus improving the injection molding stability of the mounting plate 210 and the first and second reinforcing members 240 and 250.

[0209] In some embodiments, such as Figure 16 As shown, the first reinforcing member 240 has an overall shape of a right trapezoid. The two right-angled sides of the first reinforcing member 240 are connected to the inner wall of the sleeve 220 and the mounting plate 210, respectively. The inclined side of the first reinforcing member 240 faces the axial direction of the mounting plate 210 and is inclined from the side of the first reinforcing member 240 away from the mounting plate 210 toward the mounting plate 210, so as to increase the stability of the structure between the sleeve 220 and the mounting plate 210.

[0210] In some embodiments, such as Figure 16 and Figure 18 As shown, at the line connecting the blade 230 and the outer peripheral wall of the sleeve 220, the edge on the blade 230 that first contacts the incoming flow is the leading edge of the blade 230, and is defined as the blade leading edge; the edge on the blade 230 that the fluid last leaves is the trailing edge of the blade 230, and is defined as the blade trailing edge.

[0211] The first reinforcing member 240 and the central axis of the mounting plate 210 define a first plane 203. The line connecting the trailing edge of the blade 230 to the axis of the mounting plate 210 and the central axis of the mounting plate 210 define a second plane 204. The first plane 203 and the second plane 204 define an included angle α.

[0212] To improve stress distribution, taking the second plane 204 as the starting plane, if the first plane 203 rotates clockwise along the central axis of the mounting plate 210, the included angle α between the first plane 203 and the second plane 204 is greater than 0°; if the first plane 203 rotates counterclockwise along the central axis of the mounting plate 210, α is less than 0°. When the included angle α is greater than -5°, there is a situation where the included angle between the first plane 203 and the second plane 204 in the clockwise direction is too large. In this case, it is easy to cause stress concentration on the corresponding first reinforcing member 240, which is easily affected by wind. The installation plate 210 structure is damaged. When the included angle α < 10°, the range of the included angle between the first plane 203 and the second plane 204 in the counterclockwise direction is too large. In this case, during operation, the airflow will cause some of the first reinforcing members 240 to bear greater stress, which will damage the structure of the installation plate 210. When the included angle α satisfies: α > -5°, α < 10°, the stress concentrated on the installation plate 210 can be effectively distributed to the first reinforcing member 240, thereby increasing the structural stability of the installation plate 210.

[0213] In some embodiments, such as Figure 20 As shown, the second reinforcing member 250 includes a first connecting plate 251, and the adjacent side walls of the first connecting plate 251 are respectively connected to the inner wall of the sleeve 220 and the mounting plate 210.

[0214] The second reinforcing member 250 includes a second connecting plate 252. The side of the second connecting plate 252 facing the first connecting plate 251 is connected to the first connecting plate 251. The side of the second connecting plate 252 facing the mounting plate 210 is connected to the mounting plate 210. The height of the side of the second connecting plate 252 away from the mounting plate 210 decreases from the sleeve 220 towards the axis of the mounting plate 210. That is, the side of the second connecting plate 252 away from the mounting plate 210 is inclined towards the axis of the mounting plate 210.

[0215] The second reinforcing member 250 includes a third connecting plate 253, which is connected to the second connecting plate 252 on the side facing the second connecting plate 252 and to the mounting plate 210 on the side facing the mounting plate 210. The side of the third connecting plate 253 that is connected to the second connecting plate 252 extends radially toward the axis along the mounting plate 210.

[0216] The first connecting plate 251, the second connecting plate 252, and the third connecting plate 253 are integrally formed.

[0217] In some embodiments, such as Figure 17 and Figure 19As shown, the second reinforcing member 250 and the central axis of the mounting plate 210 define a third plane 205, and the line connecting the leading edge of the blade to the axis of the mounting plate 210 and the central axis of the mounting plate 210 define a fourth plane 206. The third plane 205 and the fourth plane 206 define an included angle β.

[0218] When the included angle β > 5°, there is a possibility that the included angle range between the third plane 205 and the fourth plane 206 is too large. In this case, stress concentration will occur on some of the second reinforcing members 250, which will damage the structural stability of the mounting plate 210. If the structural strength of the mounting plate 210 meets the requirements, the corresponding second reinforcing members 250 need to be thickened or the number increased, which will increase the cost. When the included angle β < 12°, there is a possibility that the included angle range between the third plane 205 and the fourth plane 206 is too small. In this case, the stress distribution will be too concentrated, resulting in uneven distribution of structural strength on the mounting plate 210, which will damage the structural stability of the mounting plate 210. When the included angle β needs to satisfy β > 5° and β < 12°, although the centrifugal force generated by the weight of the blades 230 will accumulate on the second reinforcing member 250 adjacent to the root of the leading edge of the blades 230 when the fan 202 is rotating, the included angle range between the third plane 205 and the fourth plane 206 can effectively improve this problem and protect the structural stability of the mounting plate 210.

[0219] In some embodiments, in order to further enhance the structural strength of the mounting plate 210 and improve the stability of the connection between the mounting plate 210 and the output shaft of the motor 201, the fan 202 includes a third reinforcing member 260. The third reinforcing member 260 and the second reinforcing member 250 are located on the same side of the mounting plate 210, and the third reinforcing member 260 is located at the end of the second reinforcing member 250 facing the axis of the mounting plate 210.

[0220] like Figure 17 and Figure 20 As shown, the third reinforcing member 260 includes a first fixing ring 261, the outer peripheral wall of which is connected to the third connecting plate 253.

[0221] The third reinforcing member 260 includes a second fixing ring 262, which is located at the center of the mounting plate 210. A first fixing ring 261 is sleeved on the outer periphery of the second fixing ring 262, and the output shaft of the motor 201 passes through the center of the second fixing ring 262.

[0222] The third reinforcing member 260 includes a reinforcing plate 263, which is disposed between the first fixing ring 261 and the second fixing ring 262 for connecting the first fixing ring 261 and the second fixing ring 262. The length direction of the reinforcing plate 263 is radially arranged along the mounting plate 210.

[0223] By setting the third reinforcing member 260, the structural strength at the center of the mounting plate 210 is further increased. When the output shaft of the motor 201 passes through the center of the mounting plate 210, the second fixing ring 262 is sleeved on the output shaft of the motor 201. On the one hand, the second fixing ring 262 increases the contact area between the shaft of the mounting plate 210 and the output shaft of the motor 201, making the stress distribution of the overall structure of the mounting plate 210 more uniform when the output shaft of the motor 201 rotates. This reduces the possibility of structural damage to the shaft of the mounting plate 210 caused by the centrifugal force generated by the weight of the blades 230 when the output shaft of the motor 201 rotates. On the other hand, the reinforcing plate 263 is disposed between the first fixing ring 261 and the second fixing ring 262. The outer peripheral wall of the second fixing ring 262 is connected to the second reinforcing member 250, so that the reinforcing plate 263 provides effective support for the first fixing ring 261. The third reinforcing member 260 and the second reinforcing member 250 form an organic whole, thereby further strengthening the structural strength of the mounting plate 210 to meet the strength requirements of the axial fan 202.

[0224] In some embodiments, such as Figure 20 As shown, in order to disperse the stress concentrated on the second reinforcing member 250 and the mounting plate 210, multiple reinforcing plates 263 are provided offset from the second reinforcing member 250 along the axial direction of the mounting plate 210, and the number of reinforcing plates 263 is equal to the number of second reinforcing members 250.

[0225] In some embodiments, the number of blades 230 is increased as needed. When the number of blades 230 increases, the number of second reinforcing members 250 and reinforcing plates 263 is also increased to ensure that the structural strength of the mounting plate 210 meets the requirements of the axial fan 202. Let the number of blades 230 be X, then the number of second reinforcing members 250 and reinforcing plates 263 is 2X.

[0226] In some embodiments, in order to further enhance the connection strength between the second reinforcing member 250 and the third reinforcing member 260, the length direction of the reinforcing plate 263 and the central axis of the mounting plate 210 define a fifth plane 207, and the fifth plane 207 and the third plane 205 define an included angle γ.

[0227] When the included angle γ > 50°, there is a possibility that the included angle range between the third plane 205 and the fifth plane 207 is too large. In this case, the stress in some areas of the mounting plate 210 cannot be effectively dispersed when under load, and the stress distribution on some of the second reinforcing members 250 and the third reinforcing members 260 is too concentrated, resulting in poor structural stability of the mounting plate 210 and easy damage to the mounting plate 210 when affected by wind. When the included angle γ < 70°, there is a possibility that the included angle range between the third plane 205 and the fifth plane 207 is too small. In this case, the stress will be too concentrated, and the second reinforcing members 250 and the third reinforcing members 260 in some areas of the mounting plate 210 will bear a higher proportion of the load, and the structure of the mounting plate 210 in this area will be easily damaged. When the included angle γ satisfies γ > 50° and γ < 70°, the stress on the second reinforcing member 250 is effectively dispersed, resulting in high connection strength between the second reinforcing member 250 and the third reinforcing member 260.

[0228] In some embodiments, a gasket 280 is provided at the connection between the output shaft of the motor 201 and the mounting plate 210 to diffuse the stress concentrated at the axis of the mounting plate 210 and avoid local stress concentration that could cause the surface of the mounting plate 210 to be crushed.

[0229] In some embodiments, such as Figure 16 and Figure 18 As shown, to facilitate the installation of the gasket 280, a first mating part 270 is provided at the axis of the mounting plate 210, and the first mating part 270 and the first reinforcing member 240 are located on the same side. By providing the first mating part 270 and the gasket 280, the structural strength at the axis of the mounting plate 210 is further enhanced, avoiding any impact on the safe operation of the fan 202.

[0230] In some embodiments, such as Figure 16 and Figure 18 As shown, to prevent problems such as collapse at the connection between the shaft of the mounting plate 210 and the output shaft of the motor 201 during the operation of the fan 202, which would affect the safe operation of the fan 202, the first mating part 270 is set as a positive n-shaped deformation recess with rounded corners, and the gasket 280 is embedded in the deformation recess. Here, n is the number of sides of the first mating part 270, and n ≥ 4. When n = 4, the side length of the polygon is c = 32 mm; when n is greater than 4, the length of the perpendicular segment from the center of the polygon to the side length is d = 32 / (n-4)^0.5.

[0231] In some embodiments, such as Figure 21 and Figure 22 As shown, the recess thickness of the first mating part 270 is θ≥2.5, θ≤4.5mm.

[0232] In some embodiments, such as Figure 17 and Figure 18As shown, to further increase the structural strength at the axis of the mounting plate 210 opposite to the first mating part 270, a second mating part 290 is provided at the axis of the mounting plate 210. The second mating part 290, the second reinforcing member 250, and the third reinforcing member 260 are located on the same side of the mounting plate 210. The cross-sectional shape of the second mating part 290 is circular, and the thickness of the second mating part 290 is set to θ'.

[0233] In some embodiments, such as Figure 21 and Figure 22 As shown, when θ' ≥ 1.0θ (θ is the thickness of the recess on the front of the fan 202), there is a possibility that the thickness of the second mating part 290 is too thick. This can easily lead to material accumulation in the second mating part 290, making the local area too rigid and creating new stress concentration points. This prevents effective stress dispersion and instead generates high stress points in the surrounding area, easily causing the second mating part 290 to crack under stress, damaging the structural stability of the mounting plate 210. When θ' ≤ 1.2θ, there is a possibility that the thickness of the second mating part 290 is too thin. The second mating part 290 may not provide sufficient support, making the first mating part 270 prone to deformation and stress concentration, which may damage the structural stability of the mounting plate 210. When θ' satisfies θ'≥1.0θ and θ'≤1.2θ, the structural strength of the second mating part 290 is sufficient to support the strength of the first mating part 270. At the same time, there will be no new stress concentration points due to the excessive thickness of the second mating part 290. This increases the structural strength of the mounting plate 210 and effectively protects the stability of the mounting plate 210.

[0234] When the front recess is a quadrilateral, the radius Rh of the second mating part 290 feature on the back is 2a; when the front recess is a positive n-shaped deformation, and n is greater than 5, the radius Rh of the second mating part 290 feature on the back is 2b.

[0235] The aforementioned axial fan, by providing a first reinforcing member 240, a second reinforcing member 250, and a third reinforcing member 260 on both sides of the mounting plate 210, ensures that the axial fan 202 can meet its structural strength requirements at the center of the mounting plate 210 without the need for a bushing. Furthermore, the second and third reinforcing members 250 and 260 increase the injection molding stability of the mounting plate 210 and its related structures during production, thereby reducing production costs and improving production efficiency. The relative arrangement of the first mating part 270 and the second mating part 290 further strengthens the structure at the center of the mounting plate 210 where it connects to the output shaft of the motor 201.

[0236] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0237] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An axial flow fan, characterized in that, It includes: Installation disk; Blades, which are disposed on the outer peripheral wall of the mounting plate; A first reinforcing part is disposed on the pressure surface of the blade and close to the leading edge of the blade. The starting end of the first reinforcing part is disposed at the junction of the blade root and the outer peripheral wall of the mounting disk, and extends radially along the blade. Multiple first reinforcing parts are provided, and the multiple first reinforcing parts are distributed circumferentially along the blade, and there is a circumferential gap between adjacent first reinforcing parts.

2. The axial flow fan according to claim 1, characterized in that, The first reinforcing part is an arc-shaped reinforcing part, with its arc curvature center facing the leading edge of the blade, and the curvature radius of the first reinforcing part is set between 1 / 10 and 1 / 20 of the blade diameter.

3. The axial flow fan according to claim 1, characterized in that, From the starting end of the first reinforcing part to the ending end of the first reinforcing part, the height of the first reinforcing part gradually decreases; the height of the starting end of the first reinforcing part is set between 0.5% and 1.5% of the blade diameter.

4. The axial flow fan according to claim 1, characterized in that, The width of the first reinforcing part is set between 2mm and 4mm.

5. The axial flow fan according to claim 1, characterized in that, The circumferential gap between adjacent first reinforcing parts is set to be between 2mm and 3mm.

6. The axial fan according to claim 1, characterized in that, The suction surface of the blade is provided with a concave molding, and the concave molding corresponds to the positions of multiple first reinforcing parts.

7. The axial fan according to claim 6, characterized in that, The opening edge of the recessed molding is the first edge near the leading edge of the blade, and the second edge is opposite to the first edge. The opening width of the recessed molding is the vertical projection distance between the first edge and the second edge in the chordal direction of the blade, and the opening width of the recessed molding gradually decreases from the blade root towards the blade root 234.

8. The axial flow fan according to claim 7, characterized in that, The lines connecting the leading edge of the blade root and the leading edge of the blade tip to the axis of the mounting disk form an angle Φ, and the lines connecting the two endpoints of the first edge to the axis of the mounting disk form an angle ω, where ω satisfies: Where D is the blade diameter.

9. The axial flow fan according to claim 8, characterized in that, The recessed molding has a third edge corresponding to the first edge in the depth direction, and a fourth edge opposite to the third edge. The bottom width of the recessed molding is the vertical projection distance between the third edge and the fourth edge in the chordal direction of the blade. The opening width of the recessed molding is greater than the bottom width of the recessed molding and is in a preset ratio.

10. An outdoor unit for an air conditioner, characterized in that, It includes: The housing includes the housing air inlet and the housing air outlet; A heat exchanger is disposed inside the housing and is located near the air inlet of the housing; A compressor, which is located inside the housing; A fan, disposed inside the casing, is located on the leeward side of the heat exchanger and is positioned near the air outlet of the casing. The fan includes: Electric motor; The axial fan as described in any one of claims 1-9, wherein the mounting plate of the axial fan is connected to the motor, and the output shaft of the motor is disposed through the axis of the mounting plate.

Images