fan

Abstract

The utility model discloses a fan relates to air outlet equipment technical field, wherein, this fan includes air outlet barrel and fan assembly, and the air outlet barrel inside forms air outlet channel, and the air outlet barrel includes the wind ring, and the wind ring is located in the air outlet channel, and the first flow channel is formed in the wind ring, and the second flow channel is formed between the outer periphery of wind ring and the inner wall of air outlet channel, fan assembly includes the fan blade and the fan body, and the partial structure of fan blade is located in the first flow channel, and the fan blade is connected with the fan body, and the fan body can drive the fan blade rotation to disturb the airflow flow direction air outlet end of air outlet channel.

Description

Technical Field

[0001] This utility model relates to the field of air outlet equipment technology, and in particular to a fan. Background Technology

[0002] Typically, fan blades, driven by a motor inside the fan body, rotate and disturb the air, creating airflow to achieve airflow. To prevent users from being injured by the fan blades, an air outlet is usually installed on the outside of the fan blades.

[0003] In related technologies, in order to ensure a larger air blowing area, the fan blades and the air outlet are usually set to be mismatched. This makes it impossible for the air outlet to tightly wrap the fan blades, resulting in the airflow lacking effective guidance and constraint after leaving the fan blades, and quickly spreading in all directions, which significantly reduces the blowing efficiency. Utility Model Content

[0004] The main purpose of this invention is to propose a fan that aims to solve the technical problem of significantly reduced air blowing efficiency in related technologies.

[0005] To achieve the above objectives, the present invention provides a fan comprising: An air outlet duct, wherein an air outlet channel is formed inside the air outlet duct, the air outlet duct includes an air gathering ring, the air gathering ring is located inside the air outlet channel, a first flow channel is formed inside the air gathering ring, and a second flow channel is formed between the outer periphery of the air gathering ring and the inner wall of the air outlet channel; A fan assembly, comprising fan blades and a fan body, wherein the fan blades are disposed within the air outlet channel, and a portion of the structure of the fan blades is disposed within the first flow channel, the fan blades are connected to the fan body, and the fan body is capable of driving the fan blades to rotate, thereby disturbing the airflow to the air outlet end of the air outlet channel.

[0006] In one embodiment, the wind-gathering ring is located in the middle of the air outlet channel and is disposed near the air outlet end of the air outlet channel. The outer periphery of the wind-gathering ring is provided with a plurality of guide vanes along its circumferential direction. The plurality of guide vanes are located in the second flow channel and are connected to the inner wall of the air outlet duct.

[0007] In one embodiment, the guide vane is arranged in an arc shape; Alternatively, the guide vanes may be inclined to the rotation center axis of the fan body.

[0008] In one embodiment, the air outlet includes a first cover and a second cover, which together form the air outlet channel. The first cover is provided with an air outlet, which is connected to the air outlet end of the air outlet channel. The air gathering ring is disposed at the air outlet, and the outlet ends of the first flow channel and the second flow channel coincide with the air outlet.

[0009] In one embodiment, the first cover further includes a grille disposed at the air outlet, and the air-gathering ring is connected to the grille.

[0010] In one embodiment, half of the fan blade along its axial direction is located within the first flow channel; And / or, the cross-sectional area of ​​the first flow channel is set to gradually decrease along the air outlet direction.

[0011] In one embodiment, the fan blade includes an inner hub, an outer hub, an inner fan blade, and an outer fan blade; the inner hub is connected to the fan body, the outer hub is sleeved on the outer periphery of the inner hub and coaxially arranged with the inner hub; the outer fan blade is connected to the outer periphery of the outer hub, and the inner fan blade is disposed between the inner hub and the outer hub, connecting the inner hub and the outer hub.

[0012] In one embodiment, the outer hub has a notch, and the groove wall of the notch gradually expands from one end near the air outlet to the end away from the air outlet.

[0013] In one embodiment, the outer hub includes a first guide wall and a second guide wall connected to each other, the outer fan blade is connected to the first guide wall, and the inner fan blade is connected to the second guide wall and the inner hub; the second guide wall is inclined, and the side of the first guide wall facing the second guide wall is at an angle to the side of the second guide wall facing the first guide wall.

[0014] In one embodiment, the outer fan blades are arranged inclined to the rotation center axis of the fan body.

[0015] The fan provided by this invention, through its structural design of an air outlet and fan assembly, solves the problems of low blowing efficiency and uneven airflow distribution in traditional fans. Due to the presence of the concentrating ring, the airflow around the fan blades is precisely guided into the air outlet channel, making the airflow more orderly upon entering the channel and significantly reducing airflow scattering and eddy currents. This not only allows more airflow to pass through the outlet channel efficiently, effectively increasing air pressure and volume, but also increases the effective cross-sectional area of ​​the outlet channel by concentrating the airflow. Under the guidance of the concentrating ring, the airflow velocity is increased, and the air pressure increases accordingly, making the fan's airflow more powerful and uniform, significantly improving the overall performance and user experience of the fan, and further enhancing blowing efficiency. Simultaneously, part of the fan blade structure is located within the first flow channel, where the concentrated airflow is pressurized, while another part of the fan blades can agitate the airflow through the second flow channel towards the air outlet. Thus, the convergence of these two airflows ensures both powerful airflow and a large blowing area. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the structure of the first embodiment of the fan provided by this utility model; Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure in the diagram; Figure 3 A schematic diagram of the structure of the second embodiment of the fan provided by this utility model; Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure in the diagram; Figure 5 A schematic diagram of the fan blade provided by this utility model; Figure 6 A schematic diagram of the cross-sectional structure of the fan blade provided by this utility model; Figure 7 A schematic diagram of the third embodiment of the fan provided by this utility model.

[0018] Explanation of icon numbers: 1000, Fan; 1, Air outlet; 1a, Air outlet channel; 1b, First flow channel; 1c, Second flow channel; 11, Condensing ring; 11a, Guide vane; 12, First cover; 121, Grille; 2, Fan assembly; 21, Fan blade; 211, Inner hub; 212, Outer hub; 212a, Notch; 213, Inner fan blade; 214, Outer fan blade; 22, Fan body.

[0019] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0021] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0023] This utility model proposes a fan 1000.

[0024] Please see Figure 2 , Figure 4 as well as Figure 7 In one embodiment of the present invention, the fan 1000 includes an air outlet duct 1 and a fan assembly 2. An air outlet channel 1a is formed inside the air outlet duct 1. The air outlet duct includes a concentrating ring 11, which is located inside the air outlet channel 1a. A first flow channel 1b is formed inside the concentrating ring 11, and a second flow channel 1c is formed between the outer periphery of the concentrating ring 11 and the inner wall of the air outlet channel 1a. The fan assembly 2 includes a fan blade 21 and a fan body 22. Part of the structure of the fan blade 21 is disposed in the first flow channel 1b. The fan blade 21 is connected to the fan body 22, and the fan body 22 can drive the fan blade 21 to rotate, thereby disturbing the airflow to the air outlet end of the air outlet channel 1a.

[0025] In this embodiment, it should be noted that the fan 1000 provided by this utility model can be a household floor fan, a table fan 1000, etc., and is not limited here. The air outlet duct 1 is set on the air outlet side of the entire fan 1000, and the air concentrator ring 11 is located in the air outlet channel 1a, dividing the air outlet channel 1a into two flow channels, namely the first flow channel 1b and the second flow channel 1c. The first flow channel 1b is located in the air concentrator ring 11 and is relatively small, which can concentrate and accelerate the airflow; the second flow channel 1c is located between the outer periphery of the air concentrator ring 11 and the inner wall of the air outlet channel 1a, and is relatively large, which can guide the airflow along the inner wall of the air outlet channel 1a. Through the design of the air concentrator ring 11, the airflow is concentrated and accelerated when passing through the air concentrator ring 11, reducing the disorderly diffusion of the airflow and improving the concentration and stability of the airflow. At the same time, the design of the second flow channel 1c can further optimize the distribution of the airflow, so that the airflow flows more evenly to the air outlet. Understandably, the air outlet channel 1a is divided into a first flow channel 1b and a second flow channel 1c by the concentrating ring 11, thereby achieving airflow diversion and reducing airflow turbulence. The first flow channel 1b is wider than the second flow channel 1c. The presence of the concentrating ring 11 causes the airflow velocity to increase and the pressure to decrease when passing through the concentrating ring 11. This pressure reduction creates a low-pressure zone, causing the airflow from the second flow channel 1c to be drawn into the first flow channel 1b, further increasing the airflow in the first flow channel 1b. The first flow channel 1b is equipped with fan blades 21, which, when connected to the fan body 22, generate a powerful airflow, enabling the air outlet duct 1 to output a large air volume. Furthermore, the airflow generated by the fan assembly 2 is further compressed and accelerated when passing through the concentrating ring 11, resulting in higher speed and stronger impact force at the air outlet. The second flow channel 1c is narrower than the first flow channel 1b, with a lower airflow velocity and relatively higher pressure. This reduces the eddies and energy loss of the airflow in the outlet duct 1, and better guides the airflow, allowing it to be output more smoothly at the outlet and improving the utilization efficiency of the airflow.

[0026] The fan 1000 provided by this utility model, through its structural design of an air outlet duct 1 and a fan assembly 2, solves the problems of low blowing efficiency and uneven airflow distribution in traditional fans 1000. Due to the presence of the concentrating ring 11, the airflow around the fan blades 21 can be precisely guided into the air outlet channel 1a, making the airflow more orderly upon entering the air outlet channel 1a and significantly reducing airflow scattering and eddy currents. This not only allows more airflow to pass through the air outlet channel 1a efficiently, thereby effectively increasing wind pressure and airflow volume, but also increases the effective cross-sectional area of ​​the air outlet channel 1a by concentrating the airflow. Under the guidance of the concentrating ring 11, the airflow velocity is increased, and the wind pressure increases accordingly, making the fan 1000's airflow more powerful and uniform, significantly improving the overall performance and user experience of the fan 1000, and further enhancing blowing efficiency. Meanwhile, part of the structure of the fan blade 21 is in the first flow channel, which can be pressurized by the concentrated airflow in the first flow channel. Another part of the fan blade 21 can disturb the airflow and flow towards the air outlet through the second flow channel. Thus, under the combined airflow of the two airflows, not only is the airflow force guaranteed, but the blowing area is also guaranteed.

[0027] In one embodiment of the present invention, the wind-gathering ring 11 is located in the middle of the air outlet channel 1a and is set near the air outlet end of the air outlet channel 1a. Multiple guide vanes 11a are provided on the outer periphery of the wind-gathering ring 11 along its circumferential direction. The multiple guide vanes 11a are located in the second flow channel 1c and are connected to the inner wall of the air outlet duct 1.

[0028] In this embodiment, it should be noted that, to enhance airflow concentration, the air-gathering ring 11 is located in the middle of the air outlet channel 1a and close to the air outlet end. This effectively concentrates the airflow within the first flow channel 1b. This design makes the airflow more concentrated and directional at the air outlet, enabling more effective coverage of the target area and thus increasing the blowing area. Combined with... Figure 4 It is understood that the air-concentrating ring 11 is arranged in a ring shape, and the air-concentrating ring 11 can be fixedly connected to the circumferential inner wall of the air outlet channel 1a by means of welding, threaded connection, etc., which is not limited here. In another embodiment, the air-concentrating ring 11 can also be arranged in a trumpet shape, gradually expanding from the middle of the air outlet channel 1a towards the air outlet, so that the airflow is gradually concentrated when entering the air-concentrating ring 11, and then gradually diffuses at the air outlet, improving the coverage of the airflow. Figure 4It should be noted that the guide vanes 11a are used to connect the air outlet duct 1 and the air concentrator ring 11, thereby maintaining stable support between the air outlet duct 1 and the air concentrator ring 11. Multiple guide vanes 11a are spaced apart on the outer periphery of the air concentrator ring 11, and are installed on the outer peripheral wall of the air concentrator ring 11 by means of, but not limited to, welding or bolting. The shape of the guide vanes 11a can be straight blades, curved blades, etc., which is not limited here. Straight blades allow the airflow to smoothly change direction when passing through the guide vanes 11a; curved blades allow the airflow to change direction more effectively when passing through the guide vanes 11a, reducing airflow turbulence and energy loss. Since multiple guide vanes 11a are distributed within the second flow channel 1c, turbulence and energy loss within the second flow channel 1c can be effectively reduced. By guiding the airflow smoothly, the guide vanes 11a can reduce irregular airflow movement, making the airflow more stable.

[0029] In one embodiment of this utility model, the guide vane 11a is arranged in an arc shape.

[0030] In this embodiment, the guide vane 11a is arc-shaped, which can guide the airflow more naturally, reduce airflow resistance and turbulence when the airflow turns, and allow the airflow to flow more smoothly, thereby increasing the airflow speed. The arc-shaped guide vane 11a reduces airflow resistance, allowing the airflow to enter the first flow channel 1b more smoothly from the second flow channel 1c, improving the stability and uniformity of the airflow. This design can reduce airflow scattering, allowing the airflow to more effectively cover the target area at the outlet, thereby increasing the blowing area.

[0031] In one embodiment of this utility model, the guide vane 11a is inclined to the rotation center axis of the fan body 22.

[0032] In this embodiment, the tilt angle of the guide vane 11a can effectively change the direction of airflow. When airflow encounters the tilted guide vane 11a, the surface of the guide vane 11a guides the airflow along the tilt direction of the guide vane 11a. This design can reduce airflow resistance and turbulence when turning, allowing the airflow to change direction more smoothly. The tilted guide vane 11a can more effectively change the direction of airflow, allowing the airflow to be distributed more evenly when passing through the guide vane 11a. This design can reduce airflow scattering, increase airflow concentration, and allow the airflow to more effectively cover the target area at the outlet, thereby increasing the blowing area.

[0033] In one embodiment of the present invention, the air outlet duct 1 includes a first cover 12 and a second cover. The first cover 12 and the second cover together form an air outlet channel 1a. The first cover 12 is provided with an air outlet, which is connected to the air outlet end of the air outlet channel 1a. An air gathering ring 11 is provided at the air outlet. The outlet end of the first flow channel 1b and the outlet end of the second flow channel 1c coincide with the air outlet.

[0034] In this embodiment, combined with Figure 2 and Figure 4 The first cover 12 is part of the air outlet duct 1, and its main function is to form an air outlet and connect with the air outlet end of the air outlet channel 1a. The second cover (not shown in the figure) cooperates with the first cover 12 to jointly enclose the air outlet channel 1a. It plays a role in supporting and guiding the airflow, ensuring that the airflow flows smoothly within the air outlet channel 1a. The first cover 12 and the second cover can be connected by means of integral molding, bolt connection, snap-fit, etc. The shapes of the first cover 12 and the second cover include, but are not limited to, cylindrical, conical, and trumpet shapes, etc., and are not limited here. Figure 2 The air-concentrating ring 11 is located in the air outlet area of ​​the first cover 12. The air-concentrating ring 11 optimizes the airflow distribution, making the airflow more concentrated and uniform, reducing energy loss, and improving airflow utilization efficiency. By reducing the cross-sectional area of ​​the airflow, the air-concentrating ring 11 increases the airflow velocity as it passes through it. This increased velocity further increases the airflow pressure, thus significantly improving wind pressure. Simultaneously, the air-concentrating ring 11 reduces airflow scattering at the air outlet, making the airflow more concentrated, improving its coverage and directionality, thereby increasing the blowing area.

[0035] In one embodiment of the present invention, the first cover 12 further includes a grille 121 disposed at the air outlet, and the wind-gathering ring 11 is connected to the grille 121.

[0036] In this embodiment, combined with Figure 1 , Figure 2 as well as Figure 3 The grille 121 and the air-concentrating ring 11 can be connected by welding, integral molding, bolting, or other methods, which are not limited here. The air-concentrating ring 11 and the grille 121 can effectively guide the airflow, allowing it to flow along a predetermined path when passing through them, reducing airflow turbulence and non-uniformity. The air-concentrating ring 11 and the grille 121 can reduce airflow scattering at the air outlet, making the airflow more concentrated and improving its coverage and directionality.

[0037] In one embodiment of the present invention, half of the fan blade 21 along its axial direction is located within the first flow channel 1b; And / or, the cross-sectional area of ​​the first flow channel 1b is set to gradually decrease along the air outlet direction.

[0038] In this embodiment, half of the fan blade 21 along its axial direction is located within the first flow channel 1b. This part of the fan blade can directly utilize the guiding and constraining effect of the first flow channel to concentrate and pressurize the airflow. The other part of the fan blade 21 is located outside the first flow channel 1b, that is, the overlapping part of the first flow channel 1b and the second flow channel 1c. This part of the fan blade can effectively disturb the airflow. Through disturbance, the airflow is more uniform, avoiding the accumulation or stagnation of airflow in local areas and improving the flow efficiency of the airflow. When the airflow pressurized by the first flow channel 1b within the wind-gathering ring 11 and the airflow disturbed by the second flow channel 1c converge at the air outlet, the two airflows interact to form a stronger air outlet effect.

[0039] To further pressurize the airflow, the cross-section of the first flow channel 1b is gradually reduced, thereby driving the airflow from the area with a larger cross-section to the area with a smaller cross-section. This design can increase the airflow pressure, resulting in higher pressure at the air outlet.

[0040] In one embodiment of this utility model, the fan blade 21 includes an inner hub 211, an outer hub 212, an inner fan blade 213, and an outer fan blade 214; the inner hub 211 is connected to the fan body 22, the outer hub 212 is sleeved on the outer periphery of the inner hub 211 and is coaxially arranged with the inner hub 211; the outer fan blade 214 is connected to the outer periphery of the outer hub 212, and the inner fan blade 213 is disposed between the inner hub 211 and the outer hub 212 and connects the inner hub 211 and the outer hub 212.

[0041] In this embodiment, combined with Figure 5 It is understandable that the inner fan blade 213 and the outer fan blade 214 of the fan blade 21 respectively adopt a combination of axial flow blades and centrifugal blades. Specifically, the outer fan blade 214 adopts an axial flow blade, which has a large air volume and low wind speed; the inner fan blade 213 adopts a centrifugal blade, which has a small air volume and high wind speed. The combination of the two increases the air volume and wind speed of the fan body 22. In addition, the outer fan blade 214 and the inner fan blade 213 can be staggered, that is, the outer fan blade 214 and the inner fan blade 213 will have a phase difference, that is, the airflow does not arrive at the same position at the same time, in order to reduce the instability of the airflow and make the airflow more continuous and stable, thereby increasing the flow rate. This arrangement of the fan assembly 2 greatly improves the airflow velocity and wind force in the air outlet channel 1a. It should be noted that the airflow pressure generated by the inner fan blade 213 with centrifugal blades is relatively large. After the airflow generated by the inner fan blade 213 is mixed with the airflow generated by the outer fan blade 214, the wind force of the mixed airflow can be increased, which is beneficial to enhancing the wind force of the exhaust.

[0042] In one embodiment of the present invention, the outer hub 212 is provided with a notch 212a, and the groove wall of the notch 212a gradually expands from the end near the air outlet 1 to the end away from the air outlet 1.

[0043] In this embodiment, combined with Figure 6 The gradually expanding groove wall design of the notch 212a effectively guides the airflow, allowing it to flow along a predetermined path as it passes through the notch 212a, reducing turbulence and non-uniformity. To prevent the airflow between the inner fan blade 213 and the outer fan blade 214 from failing to converge, a notch 212a is provided on the peripheral wall of the outer hub 212. The notch 212a is correspondingly located on the peripheral wall between adjacent outer fan blades 214 connected to the outer hub 212, ensuring that the airflow can smoothly flow from the inner fan blade 213 to the outer fan blade 214 as it passes through the outer hub 212, and finally enter the air outlet duct 1.

[0044] In one embodiment of the present invention, the outer hub 212 includes a first guide wall and a second guide wall connected together, an outer fan blade 214 is connected to the first guide wall, and an inner fan blade 213 is connected to the second guide wall and the inner hub 211; the second guide wall is inclined, and the side of the first guide wall facing the second guide wall and the side of the second guide wall facing the first guide wall are set at an angle.

[0045] In this embodiment, both the first and second guide walls are used to achieve a guiding effect. It is understood that after air enters the air intake channel in the fan blade structure, it passes through the second guide wall and the inner hub 211, where it is disturbed by the outer fan blade 214. Under the influence of the disturbance from the outer fan blade 214, due to the inclined arrangement of the second guide wall, the airflow experiences centrifugal force between the second guide wall and the inner hub 211, causing the airflow to flow along the second guide wall. The airflow generated by the outer fan blade 214 is then blown out obliquely along the inclined surface of the second guide wall, thus guiding and exhausting the airflow and reducing turbulence or noise. Simultaneously, the inclined arrangement of the second guide wall allows the airflow to be blown obliquely out of the air intake channel in the fan blade structure, enabling the airflow disturbed by the outer fan blade 214 to better converge with the airflow disturbed by the outer fan blade 214, thereby improving the high-speed blowing effect. Furthermore, the use of a first guide wall and a second guide wall in the outer hub 212 can reduce the complexity of the fan blades during the manufacturing process, thereby reducing the amount of material used in the production of the outer hub 212.

[0046] In one embodiment of this utility model, the outer fan blade 214 is inclined to the rotation center axis of the fan body 22.

[0047] In this embodiment, it should be noted that, in conjunction with Figure 6 To facilitate smoother airflow, the inclined outer fan blades 214 more effectively guide the airflow and reduce resistance as it passes through them. Furthermore, by altering the airflow direction, their speed as they pass through the outer fan blades 214 can be increased. It should be noted that all arrows in the diagram below indicate the direction of airflow.

[0048] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A fan, characterized in that, The fan includes: An air outlet duct, wherein an air outlet channel is formed inside the air outlet duct, the air outlet duct includes an air gathering ring, the air gathering ring is located inside the air outlet channel, a first flow channel is formed inside the air gathering ring, and a second flow channel is formed between the outer periphery of the air gathering ring and the inner wall of the air outlet channel; A fan assembly, comprising fan blades and a fan body, wherein the fan blades are disposed within the air outlet channel, and a portion of the structure of the fan blades is disposed within the first flow channel, the fan blades are connected to the fan body, and the fan body is capable of driving the fan blades to rotate, thereby disturbing the airflow to the air outlet end of the air outlet channel.

2. The fan as described in claim 1, characterized in that, The wind-gathering ring is located in the middle of the air outlet channel and is set near the air outlet end of the air outlet channel. Multiple guide vanes are provided on the outer periphery of the wind-gathering ring along its circumference. The multiple guide vanes are located in the second flow channel and are connected to the inner wall of the air outlet duct.

3. The fan as described in claim 2, characterized in that, The guide vanes are arranged in an arc shape; Alternatively, the guide vanes may be inclined to the rotation center axis of the fan body.

4. The fan as described in claim 1, characterized in that, The air outlet includes a first cover and a second cover, which together form the air outlet channel. The first cover has an air outlet, which is connected to the air outlet end of the air outlet channel. The air gathering ring is located at the air outlet, and the outlet ends of the first flow channel and the second flow channel coincide with the air outlet.

5. The fan as described in claim 4, characterized in that, The first cover also includes a grille disposed at the air outlet, and the air-gathering ring is connected to the grille.

6. The fan as claimed in any one of claims 1 to 5, characterized in that, Half of the fan blade along its axial direction is located within the first flow channel; And / or, the cross-sectional area of ​​the first flow channel is set to gradually decrease along the air outlet direction.

7. The fan as claimed in any one of claims 1 to 5, characterized in that, The fan blades include an inner hub, an outer hub, an inner fan blade, and an outer fan blade; the inner hub is connected to the fan body, the outer hub is sleeved on the outer circumference of the inner hub and is coaxially arranged with the inner hub; the outer fan blade is connected to the outer circumference of the outer hub, and the inner fan blade is disposed between the inner hub and the outer hub, and connects the inner hub and the outer hub.

8. The fan as described in claim 7, characterized in that, The outer hub has a notch, and the groove wall of the notch gradually expands from the end near the air outlet to the end away from the air outlet.

9. The fan as described in claim 7, characterized in that, The outer hub includes a first guide wall and a second guide wall connected to each other. The outer fan blade is connected to the first guide wall, and the inner fan blade is connected to the second guide wall and the inner hub. The second guide wall is inclined, and the side of the first guide wall facing the second guide wall is at an angle to the side of the second guide wall facing the first guide wall.

10. The fan as claimed in claim 7, characterized in that, The outer fan blades are inclined to the rotation center axis of the fan body.

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