Axial fan and air conditioner

Abstract

The utility model relates to the technical field of air conditioners, and discloses an axial flow fan and an air conditioner. The axial fan includes a blade including: a blade body; and the flow guide structure is positioned on the suction surface of the blade main body and is arranged at the root of the blade main body. The distance between the flow guide structure and the blade outer edge is larger than that between the flow guide structure and the blade inner edge, that is, compared with the blade tip, the flow guide structure is closer to the blade root. In the rotating process of the fan, the flow guide structure can guide air flow to flow and scatter the air flow, so that an area with higher pressure at the root of the blade can be divided into a plurality of small areas, the pressure of each small area is reduced, channel vortexes can be inhibited, and the operation noise of the axial flow fan is reduced to a greater extent.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, and in particular to an axial flow fan and an air conditioner. Background Art

[0002] The axial flow fan used in the existing air conditioner outdoor unit is usually composed of a hub and a plurality of blades, and the plurality of blades are evenly distributed along the circumference of the hub. When the fan is running at a high speed, the blades hit the air, thereby generating periodic pressure pulsation and forming noise.

[0003] To this end, a related art discloses an axial flow fan blade, and discloses: a plurality of blades are all arranged on the outer peripheral wall of the hub, and the plurality of blades are arranged at intervals along the circumference of the hub; wherein, a blade is defined as a first blade, and in the rotation direction of the axial flow fan blade, another blade adjacent to the first blade is defined as a second blade, and the central angle formed by the most protruding point on the leading edge of the first blade, the most protruding point on the leading edge of the second blade and the center of the hub is the blade angle; among the blade angles independently formed by three adjacent blades, two adjacent blade angles are α and β respectively, and the condition is satisfied: α≠β; along the direction away from the hub, the trailing edge of the blade is sequentially provided with a sawtooth portion and a protrusion, and the sawtooth portion is provided between the opposite ends of the trailing edge; wherein the sawtooth portion includes a plurality of sawteeth sequentially provided at intervals along the direction away from the hub; the trailing edges of two adjacent blades are provided with different sawtooth portions and different protrusions; in the projection along the axial direction of the hub, the outer edges of the sawtooth constitute a Bezier curve, and the outer edges of the protrusion constitute a Bezier curve. By distributing several blades unevenly around the axis of the hub, it is avoided that the evenly distributed blades periodically hit the air when rotating at high speed, and the fundamental frequency of the rotational noise formed coincides with the fixed frequency of the fan blades to cause beating vibration, which causes the superposition of rotational noise and thus produces abnormal noise problems.

[0004] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0005] Technicians have found that there is an extremely high pressure area at the root of the blade, and there are two channel vortices with opposite exit directions between two adjacent blades at the root of the blade. The relevant technology cannot solve or alleviate the problem of the high pressure area at the root and the channel vortex.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Utility Model Content

[0007] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0008] The embodiments of the present disclosure provide an axial flow fan and an air conditioner to solve or alleviate the problems of high pressure areas at the root of blades and channel vortices.

[0009] According to a first aspect of an embodiment of the utility model, an axial flow fan is provided, comprising a blade, wherein the blade comprises: a blade body; and a flow guide structure located on a suction surface of the blade body and arranged at a root of the blade body.

[0010] In the axial flow fan provided by the embodiment of the present disclosure, the distance between the guide structure and the outer edge of the blade is greater than the distance between the guide structure and the inner edge of the blade, that is, the guide structure is arranged closer to the root of the blade than to the tip of the blade. During the rotation of the fan, the guide structure can guide the flow of air and break up the air, thereby dividing the high pressure area at the root of the blade into multiple small areas, reducing the pressure of each small area, and suppressing the channel vortex, thereby greatly reducing the operating noise of the axial flow fan.

[0011] Optionally, the flow guiding structure extends to the trailing edge of the blade body.

[0012] The trailing edge of the blade body is an important noise source. Therefore, the guide structure extends to the trailing edge of the blade body, which has little effect on the aerodynamic performance of the fan. It can also break up and disturb the airflow at the trailing edge of the blade body, thereby reducing the noise at the trailing edge and achieving noise reduction of the fan.

[0013] Optionally, the guide structure includes a plurality of guide ribs, each guide rib extends along the circumferential direction of the axial flow fan, and the plurality of guide ribs are sequentially arranged along the radial direction of the axial flow fan.

[0014] The provision of the guide ribs can break up the airflow at the guide ribs, disturb the airflow, prevent the airflow from colliding after being broken up by the guide ribs, and transform the relatively high pressure area on the suction surface into multiple smaller high pressure areas, thereby reducing the noise of the fan operation. Moreover, setting the guide structure in the form of guide ribs can also enhance the strength of the blades.

[0015] Optionally, along the rotation direction of the axial flow fan, the distance between two adjacent guide ribs decreases.

[0016] The airflow gradually flows from the area where the distance between the two guide ribs is smaller to the area where the distance between the two guide ribs is larger, so that the airflow gradually becomes stable, avoiding the collision of the airflow and the generation of noise.

[0017] Optionally, the ratio of the height of the guide rib to the radius of the axial fan is greater than or equal to 0.012 and less than or equal to 0.022; and / or, the ratio of the length of the guide rib to the radius of the axial fan is greater than or equal to 0.05 and less than or equal to 0.10; and / or, the ratio of the width of the guide rib to the radius of the axial fan is greater than or equal to 0.05 and less than or equal to 0.10.

[0018] It can prevent the guide ribs from being too small in height, width and length, which will result in a poor turbulence effect, and it can also prevent the guide ribs from being too large, which will affect the aerodynamic performance of the fan.

[0019] Optionally, the outer surface of the guide rib includes: a first outer surface; a second outer surface, and the first outer surface and the second outer surface are arranged in sequence along the rotation direction of the axial flow fan, the first outer surface is a first inclined surface and / or the second outer surface is a second inclined surface, wherein, along the rotation direction of the axial flow fan, the first inclined surface is inclined toward the air outlet direction of the axial flow fan, and the second inclined surface is inclined away from the air outlet direction of the axial flow fan.

[0020] The inclination direction of the first inclined surface and the second inclined surface can reduce the resistance of the first outer surface to the air flow and the resistance of the second outer surface to the air flow, thereby preventing the guide ribs from affecting the aerodynamic performance of the axial flow fan.

[0021] Optionally, the trailing edge of the blade body is provided with a sawtooth structure, and the flow guide structure and the sawtooth structure are sequentially arranged along the direction from the inner edge to the outer edge of the blade body.

[0022] The sawtooth structure can guide the surrounding air flow and reduce the impact of the air flow vortex, thereby reducing the vibration and noise generated when the fan rotates.

[0023] Optionally, the trailing edge of the blade body is provided with a groove.

[0024] Drawing on the groove structure that can reduce the noise and resistance of fish swimming, the trailing edge of the blade body is treated similarly. After the groove is set on the trailing edge of the blade body, it forms a groove similar to the tail fin or pectoral fin of a fish. As a result, this structure makes the boundary layer turbulent before reaching the trailing edge of the blade body, effectively reducing eddy noise, while reducing the weight of the fan and the motor load.

[0025] Optionally, there are multiple sawtooth structures, and the multiple sawtooth structures are arranged in sequence along the radial direction of the axial flow fan, and the groove is arranged between two adjacent sawtooth structures.

[0026] The groove is set between two adjacent sawtooth structures. The two sawtooth structures are equivalent to the feathers on the two wings of an owl in flight, and the groove is equivalent to the gap between the two wings. By utilizing the excellent aerodynamic and acoustic airfoil characteristics of an owl in flight, this feature is intelligently segmented and applied to the trailing edge design of the blade, which can finely control the flow at the trailing edge of the blade and greatly improve the flow and noise performance of the wind blade.

[0027] According to a second aspect of an embodiment of the utility model, an air conditioner is provided, comprising an outdoor unit, the outdoor unit comprising: an axial flow fan as described in any one of the above embodiments.

[0028] The air conditioner provided in the embodiment of the second aspect of the present application comprises the axial flow fan described in any one of the embodiments of the first aspect, and thus has all the beneficial effects of the axial flow fan described in any one of the above embodiments, which will not be elaborated here.

[0029] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0031] Figure 1 It is a surface pressure distribution diagram of the suction surface of the blade in the prior art;

[0032] Figure 2 It is a vector distribution diagram of the local blade outlet velocity in the prior art;

[0033] Figure 3 is a surface pressure distribution diagram of a blade suction surface provided by an embodiment of the present disclosure;

[0034] Figure 4 is a local vector distribution diagram of blade outlet velocity provided by an embodiment of the present disclosure;

[0035] Figure 5 is a schematic structural diagram of an axial flow fan provided by an embodiment of the present disclosure from a first perspective;

[0036] Figure 6 yes Figure 5 The structural schematic diagram of the axial flow fan from a second viewing angle is shown;

[0037] Figure 7 yes Figure 5 The structural schematic diagram of the axial flow fan from the third perspective is shown;

[0038] Figure 8yes Figure 7 The enlarged structural diagram of the middle A part;

[0039] Fig. 9 yes Figure 7 A schematic diagram of the enlarged structure of the middle B part;

[0040] Fig.10 yes Figure 5 The structural schematic diagram of the axial flow fan from the fourth perspective is shown;

[0041] Fig.11 yes Figure 5 The structural schematic diagram of the axial flow fan from the fifth viewing angle is shown;

[0042] Fig.12 yes Fig.11 The enlarged structural diagram of the middle C part;

[0043] Fig.13 yes Figure 5 The structural schematic diagram of the axial flow fan from a sixth viewing angle is shown;

[0044] Fig.14 yes Figure 5 The schematic diagram of the partial structure of the axial flow fan is shown.

[0045] Reference numerals:

[0046] 100. Axial-flow fan; 1. Hub; 2. Blades; 21. Blade body; 211. Root; 212. Tip; 213. Leading edge; 214. Trailing edge; 215. Inner edge; 216. Outer edge; 217. Sawtooth structure; 218. Groove; 219. Tooth-shaped structure; 2191. Tooth top; 2192. Tooth root; 220. Suction surface; 2201. Sub-suction surface; 221. Pressure surface; 222. Weight reduction hole; 23. Guide structure; 231. Guide rib; 2311. First outer surface; 2312. Second outer surface. DETAILED DESCRIPTION

[0047] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0048] The terms "first", "second", etc. in the specification and claims of the disclosed embodiments and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate for the disclosed embodiments described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0049] In the embodiments of the present disclosure, the terms "upper", "lower", "inside", "middle", "outside", "front", "back" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the embodiments of the present disclosure and their embodiments, and are not intended to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction. Moreover, in addition to being used to indicate directions or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in certain circumstances. For those of ordinary skill in the art, the specific meanings of these terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0050] In addition, the terms "disposed", "connected", and "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0051] Unless otherwise stated, the term "plurality" means two or more.

[0052] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0053] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A, or B, or, A and B.

[0054] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

[0055] Combination Figure 5-14 As shown, an embodiment of the present disclosure provides an axial flow fan 100 for an air conditioner.

[0056] The air conditioner includes an outdoor unit and an indoor unit. The outdoor unit includes an axial flow fan 100 and an outdoor heat exchanger. The outdoor unit is provided with an air inlet and an air outlet. The axial flow fan 100 is used to drive air flow to be sucked in from the air inlet, and after heat exchange with the outdoor heat exchanger, the air flows out from the air outlet.

[0057] The axial flow fan 100 includes a hub 1 and blades 2 .

[0058] like Figure 6 As shown, each blade 2 includes an inner edge 215, an outer edge 216, a leading edge 213 and a trailing edge 214. Figure 6 The front edge of the blade 2 forms a leading edge 213 of the blade 2, the rear edge of the blade 2 forms a trailing edge 214 of the blade 2, and the leading edge 213 and the trailing edge 214 of the blade 2 are arranged opposite to each other.

[0059] The outer edge of the trailing edge 214 and the leading edge 213 of the same blade 2 is connected to form the outer edge 216 of the blade 2, and the inner edge of the trailing edge 214 and the leading edge 213 of the same blade 2 is connected to form the inner edge 215 of the blade 2. The inner edge 215 of the blade 2 is connected to the peripheral wall of the hub 1, and each blade 2 also includes two side surfaces along the axial direction of the hub 1 to form a suction surface 220 and a pressure surface 221 respectively.

[0060] The blade 2 includes a root 211 and a tip 212. The root 211 is connected to the hub 1. The inner edge of the root forms the inner edge, and the outer edge of the tip forms the outer edge. Figure 7 and Fig. 9 As shown, the suction surface 220 of the tip 212 is provided with a plurality of tooth-shaped structures 219 , each tooth-shaped structure 219 extends from the inner edge 215 to the outer edge 216 of the blade 2 , and the plurality of tooth-shaped structures 219 are sequentially arranged along the circumference of the axial flow fan 100 .

[0061] The extension direction of each tooth-shaped structure 219 and the arrangement of multiple tooth-shaped structures 219 in sequence along the circumference of the axial flow fan 100 imitate the shape of the multi-layer feathers of a bird's wing. The distribution of feathers in the wings of the biological world is used for bionics, so that the blade 2 can fully disperse the impact airflow at the multiple tooth-shaped structures 219, effectively disperse the rotation base frequency generated by the airflow impacting the multiple tooth-shaped structures 219 of the blade 2, prevent the superposition of noises with the same frequency, and effectively reduce the rotation noise of the axial flow fan 100, thereby improving the noise reduction effect of the axial flow fan 100.

[0062] Alternatively, if Figure 7 As shown, the suction surface 220 of the blade 2 is provided with a weight-reducing hole 222 , and the multi-segment tooth-shaped structure 219 is provided between the weight-reducing hole 222 and the trailing edge 214 of the blade 2 .

[0063] There are multiple weight-reducing holes 222, which are sequentially arranged along the circumference of the axial flow fan 100. The area of ​​the weight-reducing holes 222 gradually decreases along the wind direction from the trailing edge 214 to the leading edge 213 of the blade 2. The weight-reducing holes 222 can not only reduce the weight of the blade 2, but also have a certain effect on improving the noise of the axial flow fan 100.

[0064] The multi-segment tooth-shaped structure 219 is disposed between the weight-reducing hole 222 and the trailing edge 214 of the blade 2, so that the multi-segment tooth-shaped structure 219 does not affect the setting of the weight-reducing hole 222. Moreover, compared with the multi-segment tooth-shaped structure 219 disposed between the leading edge 213 of the blade 2 and the weight-reducing hole 222, the present application disposes the multi-segment tooth-shaped structure 219 between the trailing edge 214 of the blade 2 and the weight-reducing hole 222, that is, the distance between the multi-segment tooth-shaped structure 219 and the trailing edge 214 of the blade 2 is smaller than the distance between the multi-segment tooth-shaped structure 219 and the leading edge 213, which can reduce the noise of the trailing edge 214 of the blade 2, and has a more significant effect on reducing the noise of the axial flow fan 100.

[0065] Alternatively, if Figure 7 and Fig. 9 As shown, one segment of the multi-segment tooth structure 219 is disposed at the trailing edge 214 of the blade 2 .

[0066] The tooth-shaped structure 219 provided on the trailing edge 214 of the blade 2 can be used to guide the airflow, reduce the collision between airflows, and reduce noise.

[0067] The suction surface 220 of the blade 2 is provided with a multi-segment toothed structure 219 including a multi-segment suction surface 2201. Along the direction from the leading edge 213 to the trailing edge 214 of the blade 2, the multi-segment suction surface 2201 is arranged in sequence to form a step shape so that the thickness of the blade 2 gradually decreases. A segment of toothed structure 219 is provided between two adjacent segments of the suction surface 2201.

[0068] like Fig.14 As shown, the connection between two adjacent sections of the suction surface 2201 forms a step, so that the suction surface 220 of the blade 2 is provided with a plurality of sections of tooth-shaped structures 219 to form a stepped layered structure, and the thickness of the blade 2 is provided with a plurality of sections of tooth-shaped structures 219 gradually decreases along the direction from the leading edge 213 to the trailing edge 214 of the blade 2. The number of steps is equal to the number of sections of the tooth-shaped structures 219 and corresponds one to one. A section of tooth-shaped structure 219 is provided at one step, so that the suction surface 220 of the blade 2 is provided with a plurality of sections of tooth-shaped structures 219 to form a wave-like layered sense, so as to further simulate the characteristics of the wing, and form a multi-level and multi-dimensional wing noise reduction structure, similar to a multi-layer fish scale-like stacked structure, which effectively improves the vortex and separation noise of the trailing edge 214.

[0069] The height difference between any two adjacent sections of the suction surface 2201 may be equal or unequal. In other words, the thickness of the blade 2 where the multi-section toothed structure 219 is provided may be a decreasing arithmetic progression or not along the direction from the leading edge 213 to the trailing edge 214 of the blade 2.

[0070] Optionally, the thickness of the blade 2 at the locations of at least two sections in the multi-section toothed structure 219 is equal.

[0071] The thickness of the blade 2 at the locations where two sections of the tooth-shaped structures 219 are located may be equal, or the thickness of the blade 2 at the locations where more than two sections of the tooth-shaped structures 219 are located may be equal.

[0072] The thickness of the blade 2 at the positions of at least two sections in the multi-section tooth-shaped structure 219 is equal, which also has the effect of reducing noise and can prevent the blade 2 from being too thin.

[0073] Alternatively, if Figure 6 As shown, the trailing edge 214 of the blade 2 is provided with a groove 218 , and the multi-stage tooth-shaped structure 219 is provided on a side of the groove 218 facing away from the hub 1 .

[0074] Drawing on the groove 218 structure that can reduce the noise and resistance of fish swimming, a similar treatment is performed on the trailing edge 214 of the blade 2. After the groove 218 is set on the trailing edge 214 of the blade 2, a groove 218 similar to that at the tail fin or pectoral fin of a fish is formed. Thus, this structure makes the boundary layer turbulent before reaching the trailing edge 214 of the blade 2, effectively reducing eddy noise, while reducing the weight of the fan and the load on the motor.

[0075] Optionally, at least one segment of the tooth-shaped structure 219 among the multiple segments of the tooth-shaped structure 219 penetrates through the groove wall of the groove 218 .

[0076] When at least one section of the tooth-shaped structure 219 passes through the groove wall of the groove 218 , the length of the section of the tooth-shaped structure 219 can be increased, thereby enhancing the noise reduction effect of the tooth-shaped structure 219 .

[0077] It is understandable that all segments of the tooth-shaped structure 219 may not penetrate the groove wall of the groove 218 to avoid the strength of the blade 2 at the groove 218 being too low.

[0078] The depth of the groove 218 is L7, and 0.1≤L7 / R≤0.16.

[0079] When L7 / R is less than 0.1, the depth of the groove 218 is small and the noise reduction effect of the groove 218 is not obvious; when L7 / R is greater than 0.16, the depth of the groove 218 is too large and the strength of the blade 2 is reduced.

[0080] The opening width of the groove 218 is L8, and 0.2≤L8 / R≤0.31.

[0081] When L8 / R is less than 0.2, the opening width of the groove 218 will be small, and the noise reduction effect of the groove 218 will not be obvious; when L8 / R is greater than 0.31, the opening width of the groove 218 will be too large, and the strength of the blade 2 will be reduced.

[0082] Optionally, the tooth tops 2191 of two adjacent sections of the tooth-shaped structure 219 are arranged opposite to each other, and the tooth roots 2192 are arranged opposite to each other, which can simplify the molding process of the blade 2 while ensuring the noise reduction effect.

[0083] The tooth-shaped structure 219 can guide the airflow, reduce the impact between the airflows, and reduce vibration and noise. The tooth tops 2191 of two adjacent sections of the tooth-shaped structure 219 are arranged relative to each other, and the tooth roots 2192 are arranged relative to each other, which can better guide the airflow, so that the airflow direction guided by each section of the tooth-shaped structure 219 remains consistent, reducing the impact force between the airflows, thereby further reducing vibration and noise.

[0084] It is understandable that the tooth tops 2191 of two adjacent layers of tooth-shaped structures 219 may be staggered with each other, and the tooth roots 2192 may be staggered with each other.

[0085] Optionally, the distance between the tooth tops 2191L10 of two adjacent sections of the tooth-shaped structure 219 is greater than or equal to 10 mm. Alternatively, the distance between the tooth roots 2192L9 of two adjacent sections of the tooth-shaped structure 219 is greater than or equal to 10 mm.

[0086] The distance between the tooth tops 2191 or the tooth roots 2192 of two adjacent tooth structures 219 is less than 10 mm. The distance between the two adjacent tooth structures 219 is too small, so the impact effect of the airflow guided by the two adjacent tooth structures 219 is strong, which is not conducive to vibration reduction and noise reduction.

[0087] Therefore, the distance between the tooth tops 2191 of two adjacent tooth structures 219 is set to be greater than or equal to 10 mm, or the distance between the tooth roots 2192 of two adjacent tooth structures 219 is set to be greater than or equal to 10 mm. This can reduce the impact force between the airflows guided by the two adjacent tooth structures 219, which is beneficial to vibration reduction and noise reduction.

[0088] Optionally, the distance L10 between the tooth tops 2191 of two adjacent sections of the tooth-shaped structure 219 is greater than or equal to 12 mm and less than or equal to 20 mm, such as 12 mm, 14 mm, 16 mm, 18 mm or 20 mm. Alternatively, the distance L9 between the tooth roots 2192 of two adjacent sections of the tooth-shaped structure 219 is greater than or equal to 12 mm and less than or equal to 20 mm, such as 12 mm, 14 mm, 16 mm, 18 mm or 20 mm.

[0089] Each tooth structure 219 includes a plurality of teeth connected in sequence along the direction from the inner edge 215 to the outer edge 216 of the blade 2, and the distances between the teeth are equal or unequal.

[0090] The number of teeth in each tooth-shaped structure 219 is 3-10. If the number of teeth is less than 3, the width of a single tooth will be too large or the distance between two adjacent teeth will be too large, causing the blade 2 to divert too much airflow when rotating, resulting in the blade 2 being unable to accelerate the surrounding air force, causing the outdoor heat exchanger to be unable to exchange heat normally; if the number of teeth is greater than 10, the width of a single tooth will be too small or the distance between two adjacent teeth will be too small, causing the tooth-shaped structure 219 to divert airflow and reduce fan vibration and noise.

[0091] The toothed structure 219 on the same blade 2 is greater than or equal to 2 segments, for example Fig.14 The number of toothed structures 219 can be determined flexibly according to the size and shape of the blade 2, and is within the protection scope of the present application.

[0092] The teeth of the tooth structure 219 may be in various shapes such as V-shape, arc-shape, trapezoidal, rectangular, etc., which are not limited here and are all within the protection scope of this application.

[0093] The blade 2 includes a blade body 21 and a flow guide structure 23. The multi-stage tooth structure 219 is provided on the blade body 21. The leading edge 213, trailing edge 214, root 211, tip 212, inner edge 215, outer edge 216, and suction surface 220 of the blade 2 are respectively the leading edge 213, trailing edge 214, root 211, tip 212, inner edge 215, outer edge 216, and suction surface 220 of the blade body 21.

[0094] The flow guiding structure 23 is located on the suction surface 220 of the blade body 21 and is provided at the root 211 of the blade body 21 .

[0095] Pressure distribution diagram of the suction surface 220 of the blade body 21 Figure 1 And the appropriate distribution diagram of blade 2 outlet velocity Figure 2 It can be seen that in the related art, there is a relatively high pressure area (such as Figure 1 In addition, it can be seen from the velocity vector diagram that there are two channel vortices with opposite exit directions (such as Figure 2 (indicated by the arrow in the middle).

[0096] like Figure 8 , Figures 10 to 12 As shown, a flow guide structure 23 is provided at the root 211 of the blade body 21, which can break up the airflow at the root 211 of the blade body 21, so that the broken up airflow is evenly dispersed, thereby suppressing the channel vortex and reducing the high-pressure area, which can play a certain role in noise reduction.

[0097] Pressure distribution diagram of the suction surface 220 of the blade body 21 Figure 3 And the appropriate distribution diagram of blade 2 outlet velocity Figure 4 It can be seen that the existence of the guide structure 23 not only suppresses the outlet channel vortex (such as Figure 4 The relatively high pressure area of ​​the suction surface 220 is transformed into three smaller high pressure areas (such as Figure 3 (as shown in the enlarged image on the right side of the figure), which reduces the high-voltage area and can reduce noise.

[0098] Optionally, the flow guiding structure 23 extends to the trailing edge 214 of the blade body 21 .

[0099] The trailing edge 214 of the blade body 21 is an important noise source. Therefore, the guide structure 23 extends to the trailing edge 214 of the blade body 21, which has little effect on the aerodynamic performance of the fan. It can also break up and disturb the airflow at the trailing edge 214 of the blade body 21, thereby reducing the noise at the trailing edge 214 and achieving noise reduction of the fan.

[0100] Optionally, the guide structure 23 includes a plurality of guide ribs 231, which are arranged protruding from the suction surface 220 of the blade body 21. Each guide rib 231 extends along the circumference of the axial flow fan 100, and the plurality of guide ribs 231 are arranged in sequence along the radial direction of the axial flow fan 100.

[0101] The arrangement of the guide rib 231 can break up the airflow at the guide rib 231, disturb the airflow, prevent the airflow after being broken up by the guide rib 231 from colliding, and change the relatively high pressure area of ​​the suction surface 220 into multiple smaller high pressure areas, thereby reducing the noise of the fan operation. Moreover, setting the guide structure 23 in the form of the guide rib 231 can also enhance the strength of the blade 2.

[0102] It can be understood that the guide structure 23 can also be other structural forms besides the guide ribs 231, such as guide grooves.

[0103] Optionally, the distance between two adjacent guide ribs 231 decreases along the rotation direction of the axial flow fan 100. In this way, the airflow gradually flows from the smaller distance between the two guide ribs 231 to the larger distance between the two guide ribs 231, making the airflow gradually smoother and avoiding the collision of the airflow and the generation of noise.

[0104] Along the rotation direction of the axial flow fan 100 , the distance between two adjacent guide ribs 231 gradually decreases.

[0105] The width of the guide ribs 231 may be increased along the flow direction of the axial flow fan 100, thereby reducing the distance between two adjacent guide ribs 231; or the guide ribs 231 may be inclined, thereby reducing the distance between two adjacent guide ribs 231 along the rotation direction of the axial flow fan 100.

[0106] The radius of the axial flow fan 100 is defined as R, and the height of the guide rib 231 is defined as H. 0.012≤H / R≤0.022.

[0107] When H / R is less than 0.012, it means that the height of the guide rib 231 is relatively small, the turbulence effect of the guide rib 231 is not strong, and the noise reduction effect will be worse; when H / R is greater than 0.022, it means that the height of the guide rib 231 is relatively large, the guide rib 231 will affect the airflow and reduce the aerodynamic performance of the fan.

[0108] The length L1 of the guide rib 231 is 0.05≤L1 / R≤0.1.

[0109] When L1 / R is less than 0.05, it means that the guide rib 231 is short, the turbulence effect of the guide rib 231 is not strong, and the noise reduction effect will be worse; when L1 / R is greater than 0.1, it means that the guide rib 231 is high, the guide rib 231 will affect the airflow and reduce the aerodynamic performance of the fan.

[0110] The width L4 of the guide rib 231 is 0.05≤L4 / R≤0.1.

[0111] When L4 / R is less than 0.05, it means that the width of the guide rib 231 is small, the turbulence effect of the guide rib 231 is not strong, and the noise reduction effect will be worse; when L4 / R is greater than 0.1, it means that the width of the guide rib 231 is large, the guide rib 231 will affect the airflow and reduce the aerodynamic performance of the fan.

[0112] The average distance L5 between two adjacent guide ribs 231 is 0.03≤L5 / R≤0.06.

[0113] When L5 / R is less than 0.03, it means that the distance between two adjacent guide ribs 231 is small, the flow disturbance effect of the guide rib 231 is not strong, and the noise reduction effect will be worse; when L5 / R is greater than 0.06, it means that the distance between two adjacent guide ribs 231 is large, the flow disturbance effect of the guide rib 231 will also be worse, and the noise reduction effect will be worse.

[0114] The distance L2 between the guide rib 231 closest to the inner edge 215 of the blade body 21 and the inner edge 215 of the blade body 21 is 0.15≤L2 / R≤0.2.

[0115] The distance L3 between the guide rib 231 closest to the outer edge 216 of the blade body 21 and the inner edge 215 of the blade body 21 is 0.05≤L3 / R≤0.08.

[0116] The number of the guide ribs 231 is greater than or equal to two. Figure 7 As shown, there are three guide ribs 231 on each blade.

[0117] Optionally, the outer surface of the guide rib 231 includes a first outer surface 2311 and a second outer surface 2312 .

[0118] Along the rotation direction of the axial flow fan 100, the first outer surface 2311 and the second outer surface 2312 are arranged in sequence, the first outer surface 2311 is a first inclined surface and / or the second outer surface 2312 is a second inclined surface, along the rotation direction of the axial flow fan 100, the first inclined surface is inclined toward the air outlet direction of the axial flow fan 100, and the second inclined surface is inclined away from the air outlet direction of the axial flow fan 100.

[0119] The inclination directions of the first inclined surface and the second inclined surface can reduce the resistance of the first outer surface 2311 to the air flow and the resistance of the second outer surface 2312 to the air flow, thereby preventing the guide ribs 231 from affecting the aerodynamic performance of the axial flow fan 100 .

[0120] The first outer surface 2311 and the second outer surface 2312 may be flat surfaces or curved surfaces such as arc-shaped surfaces.

[0121] Optionally, the trailing edge 214 of the blade body 21 is provided with a sawtooth structure 217 , and the flow guide structure 23 and the sawtooth structure 217 are sequentially arranged along the direction from the inner edge 215 to the outer edge 216 of the blade body 21 .

[0122] The sawtooth structure 217 can guide the surrounding air flow and reduce the impact of the air flow vortex, thereby reducing the vibration and noise generated when the fan rotates.

[0123] Alternatively, if Fig.13 As shown, there are multiple sawtooth structures 217 , and the multiple sawtooth structures 217 are sequentially arranged along the radial direction of the axial flow fan 100 , and the groove 218 is arranged between two adjacent sawtooth structures 217 .

[0124] The groove 218 is arranged between two adjacent sawtooth structures 217. The two sawtooth structures 217 are respectively equivalent to the feathers on the two wings of an owl when it is flying, and the groove 218 is equivalent to the gap between the two wings. By utilizing the excellent aerodynamic and acoustic airfoil characteristics of an owl in flight, such characteristics are intelligently segmented and applied to the design of the trailing edge 214 of the blade 2, so that the flow of the trailing edge 214 of the blade 2 can be finely controlled, greatly improving the flow and noise performance of the wind blade.

[0125] The distance between the guide rib 231 closest to the outer edge 216 of the blade body 21 and the sawtooth structure 217 is L6, and 0.04≤L6 / R≤0.07.

[0126] According to a second aspect of an embodiment of the utility model, an air conditioner is provided, including an outdoor unit, the outdoor unit including: an axial flow fan 100 as described in any one of the above embodiments.

[0127] The air conditioner provided by the embodiment of the utility model comprises the axial flow fan 100 described in any one of the above embodiments, and thus has all the beneficial effects of the axial flow fan 100 described in any one of the above embodiments, which will not be described in detail here.

[0128] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An axial flow fan, characterized in that: Including blades, the blades include: Blade body; The flow guide structure is located on the suction side of the blade body and is arranged at the root of the blade body; The trailing edge of the blade body is provided with a sawtooth structure, and the flow guide structure and the sawtooth structure are sequentially arranged along the direction from the inner edge to the outer edge of the blade body.

2. The axial flow fan according to claim 1, characterized in that: The flow guiding structure extends to the trailing edge of the blade body.

3. The axial flow fan according to claim 1, characterized in that: The flow guiding structure comprises a plurality of flow guiding ribs, each of which extends along the circumferential direction of the axial flow fan, and the plurality of flow guiding ribs are sequentially arranged along the radial direction of the axial flow fan.

4. The axial flow fan according to claim 3, characterized in that: Along the rotation direction of the axial flow fan, the distance between two adjacent guide ribs decreases.

5. The axial flow fan according to claim 3, characterized in that: The ratio of the height of the guide rib to the radius of the axial flow fan is greater than or equal to 0.012 and less than or equal to 0.022; and / or, The ratio of the length of the guide rib to the radius of the axial flow fan is greater than or equal to 0.05 and less than or equal to 0.10; and / or, The ratio of the width of the guide rib to the radius of the axial flow fan is greater than or equal to 0.05 and less than or equal to 0.

10.

6. The axial flow fan according to claim 3, characterized in that: The outer surface of the guide rib includes: a first outer surface; The second outer surface, along the rotation direction of the axial flow fan, the first outer surface and the second outer surface are arranged in sequence, the first outer surface is a first inclined surface and / or the second outer surface is a second inclined surface, wherein, along the rotation direction of the axial flow fan, the first inclined surface is inclined toward the air outlet direction of the axial flow fan, and the second inclined surface is inclined away from the air outlet direction of the axial flow fan.

7. The axial flow fan according to any one of claims 1 to 6, characterized in that: The trailing edge of the blade body is provided with a groove.

8. The axial flow fan according to claim 7, characterized in that: There are multiple sawtooth structures, which are arranged in sequence along the radial direction of the axial flow fan, and the groove is arranged between two adjacent sawtooth structures.

9. An air conditioner, characterized in that: Including outdoor unit, the outdoor unit includes: An axial flow fan as claimed in any one of claims 1 to 8.

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