Fan blade device

Abstract

The utility model discloses a fan blade device which comprises a fan blade, a plurality of first flow guide structures and a plurality of second flow guide structures. The fan blade comprises a hub part and a plurality of blade parts. The blade parts are connected to the periphery of the hub part. Each blade part is provided with a front surface and a back surface which are opposite to each other; the first flow guide structures are arranged on the blade parts and comprise a plurality of first flow guide convex blocks. The first flow guiding protruding blocks protrude out of the front faces. Each first flow guide bump is provided with a plurality of first convex parts; a first micro-channel is formed between any two adjacent first convex parts; the second flow guide structures are arranged on the blade parts and comprise a plurality of second flow guide convex blocks. The second flow guiding protruding blocks protrude out of the reverse faces. Each second flow guide bump is provided with a plurality of second convex parts; and a second micro-channel is formed between any two adjacent second convex parts.

Description

TECHNICAL FIELD

[0001] The utility model relates to a fan blade device, in particular to a fan blade device with a flow guide structure. BACKGROUND

[0002] A fan is a device capable of causing air flow by driving a fan blade to rotate. Fans are widely used. For example, fans can be household electric fans for cooling and heat dissipation fans for dissipating heat from electronic components such as CPUs in electronic devices.

[0003] Generally, a fan includes a fan blade for driving air flow and a driving motor for driving the fan blade to rotate. The structure of the fan blade greatly affects the effect and performance of the fan. However, the fan blade generates a high-speed air flow zone during operation, and the air flow vortex formed in the high-speed air flow zone generates noise due to the impact on the fan blade, thereby affecting the user's experience. Therefore, how to reduce the noise generated by the fan during operation is one of the problems that researchers should solve. SUMMARY

[0004] The utility model provides a fan blade device to reduce the noise generated by the fan blade device during operation.

[0005] An embodiment of the utility model discloses a fan blade device including a fan blade, a plurality of first flow guide structures, and a plurality of second flow guide structures. The fan blade includes a hub portion and a plurality of blade portions. The blade portions are connected around the hub portion. Each blade portion has a front surface and a back surface facing away from each other. The first flow guide structures are disposed on the blade portions and include a plurality of first flow guide protrusions. The first flow guide protrusions protrude from the front surfaces. Each first flow guide protrusion has a plurality of first protrusions. A first micro flow channel is formed between any two adjacent first protrusions. The second flow guide structures are disposed on the blade portions and include a plurality of second flow guide protrusions. The second flow guide protrusions protrude from the back surfaces. Each second flow guide protrusion has a plurality of second protrusions. A second micro flow channel is formed between any two adjacent second protrusions.

[0006] The fan blade device of the preceding paragraph, wherein the front face and the back face of each of the blade portions each further has a third reference line and a fourth reference line, the third reference line is parallel to the second reference line, the fourth reference line is parallel to the first reference line, the fourth reference line is close to the leeward side of the blade portion and is located at 3 / 4 of the third reference line, at least part of the first flow guide protrusions are distributed between the leeward side of the blade portion and the fourth reference line located on the front face, and at least part of the second flow guide protrusions are distributed between the leeward side of the blade portion and the fourth reference line located on the back face.

[0007] The fan blade device of the preceding paragraph, wherein the front face and the back face of each of the blade portions each further has a third reference line and a fourth reference line, the third reference line is parallel to the second reference line, the fourth reference line is parallel to the first reference line, the fourth reference line is close to the leeward side of the blade portion and is located at 3 / 4 of the third reference line, at least part of the first flow guide protrusions are distributed between the leeward side of the blade portion and the fourth reference line located on the front face, and at least part of the second flow guide protrusions are distributed between the leeward side of the blade portion and the fourth reference line located on the back face.

[0008] The fan blade device of the preceding paragraph, wherein the first protrusions include a first sub-protrusion and two second sub-protrusions, the first sub-protrusion is located between the two second sub-protrusions, the height of the first sub-protrusion is greater than the height of the two second sub-protrusions, the second protrusions include a third sub-protrusion and two fourth sub-protrusions, the third sub-protrusion is located between the two fourth sub-protrusions, and the height of the third sub-protrusion is greater than the height of the two fourth sub-protrusions.

[0009] The fan blade device of the preceding paragraph, wherein the angle between the first sub-protrusion of each of the first flow guide protrusions and a straight line extending radially from the hub portion is greater than or equal to 10 degrees and less than or equal to 170 degrees, and the angle between the third sub-protrusion of each of the second flow guide protrusions and a straight line extending radially from the hub portion is greater than or equal to 10 degrees and less than or equal to 170 degrees.

[0010] The fan blade device, wherein a maximum height of the first sub-convex part and a maximum height of the third sub-convex part are 0.6 mm, a maximum height of each of the two second sub-convex parts and a maximum height of each of the two fourth sub-convex parts are 0.42 mm, a maximum distance between the first sub-convex part and any of the two second sub-convex parts and a maximum distance between the third sub-convex part and any of the two fourth sub-convex parts are 0.45 mm, and a maximum distance between the first sub-convex part and any of the two first micro flow channels and a maximum distance between the third sub-convex part and any of the two second micro flow channels are 0.25 mm.

[0011] The fan blade device, wherein an included angle between a vertical line connecting a vertex of each of the first sub-convex parts to a corresponding front surface and a line connecting the vertex of the first sub-convex part to any of the two first micro flow channels is 37 degrees, and an included angle between a vertical line connecting a vertex of each of the third sub-convex parts to a corresponding back surface and a line connecting the vertex of the third sub-convex part to any of the two second micro flow channels is 37 degrees.

[0012] The fan blade device, wherein a distance between the first sub-convex part of each of the first flow guide protrusions and an adjacent first flow guide protrusion parallel to a center line of the front surface is greater than or equal to a width of each of the first flow guide protrusions, and a distance between the third sub-convex part of each of the second flow guide protrusions and an adjacent second flow guide protrusion parallel to a center line of the back surface is greater than or equal to a width of each of the second flow guide protrusions.

[0013] The fan blade device, wherein a length of each of the first flow guide protrusions and a length of each of the second flow guide protrusions are 1.8 mm, and a width of each of the first flow guide protrusions and a width of each of the second flow guide protrusions are 1.2 mm.

[0014] The fan blade device, wherein the fan blade further comprises an outer ring part connected to a side of the blade parts away from the hub part and surrounding the blade parts.

[0015] According to the fan blade device of the above-mentioned embodiments, since the fan blade of the fan blade device is provided with the first flow guide structure and the second flow guide structure, the air flow generated by the operation of the fan blade can be adjusted through the first micro flow channel and the second micro flow channel, so that the air flow is smoother, and the air flow vortex generated in the high-speed area of the air flow at the front surface and the back surface of the fan blade is greatly reduced, that is, the air flow is separated from the front surface and the back surface of the fan blade when the fan blade rotates at high speed to reduce the air flow impacting the fan blade. In this way, the noise generated when the fan blade operates can be reduced to improve the user experience.

[0016] The above description of the present application and the following description of the embodiments are used to demonstrate and explain the principles of the present application, and provide further explanation of the scope of the patent application of the present application. Attached Figure Description

[0017] Figure 1 This is a perspective view of the fan blade device according to an embodiment of the present invention.

[0018] Figure 2 for Figure 1 Another three-dimensional schematic diagram of the fan blade device.

[0019] Figure 3 for Figure 1 A partially enlarged plan view of the fan blade assembly.

[0020] Figure 4 for Figure 2 A partially enlarged plan view of the fan blade assembly.

[0021] Figure 5 for Figure 3 A partially enlarged plan view of the fan blade assembly.

[0022] Figure 6 for Figure 4 A partially enlarged plan view of the fan blade assembly.

[0023] Figure 7 for Figure 1 A cross-sectional schematic diagram of the first guide protrusion of the fan blade assembly.

[0024] Figure 8 This is a schematic diagram of the noise distribution on the front of the fan blades of a comparative fan blade device.

[0025] Figure 9 This is a schematic diagram of the noise distribution on the front of the fan blade of the fan blade device according to an embodiment of the present invention.

[0026] Figure 10 This is a schematic diagram of the noise distribution on the reverse side of the fan blades of a comparative fan blade device.

[0027] Figure 11 This is a schematic diagram of the noise distribution on the reverse side of the fan blade of the fan blade device according to an embodiment of the present invention.

[0028] Figure 12 This is a schematic diagram of the airflow distribution of the fan blades in a comparative example fan blade device.

[0029] Figure 13 This is a schematic diagram of the airflow distribution of the fan blades in the fan blade device according to an embodiment of the present invention.

[0030] In the attached figures, the following labels are used:

[0031] 10: Fan blade assembly

[0032] 20: Fan blades

[0033] 21: Wheel hub

[0034] 22: Blade section

[0035] 221: Front

[0036] 222: reverse

[0037] 223: Windward side

[0038] 224: Leeward side

[0039] 30: First flow guiding structure

[0040] 31: First guide bump

[0041] 311: First convex part

[0042] 3111:The first sub-convex part

[0043] 3112: The second sub-convex part

[0044] 40: Second flow guiding structure

[0045] 41: Second guide bump

[0046] 411: Second convex part

[0047] 4111: The third sub-convex part

[0048] 4112:The fourth sub-convex part

[0049] 50: Outer Ring Road

[0050] A~D: Direction

[0051] A1, A2, A1a, A2a: High-speed airflow region

[0052] C1: First microchannel

[0053] C2: Second microchannel

[0054] D1~D3: Spacing

[0055] H1, H2: Height

[0056] L: Length

[0057] L1: First baseline

[0058] L2: Second baseline

[0059] L3: Third baseline

[0060] L4: Fourth baseline

[0061] L5, L6, L11: Centerline

[0062] L7, L8: Straight lines

[0063] L9, L10: Connection

[0064] R1~R4: Included angle

[0065] T: Tangent

[0066] W: Width Detailed Implementation

[0067] Please see Figure 1 and Figure 2 . Figure 1 This is a perspective view of the fan blade device according to an embodiment of the present invention. Figure 2 for Figure 1 Another three-dimensional schematic diagram of the fan blade device.

[0068] The fan blade device 10 of this embodiment is used, for example, in devices such as personal computers, servers, or home appliances, and includes a fan blade 20, a plurality of first airflow guiding structures 30, and a plurality of second airflow guiding structures 40. The fan blade 20 includes a hub portion 21 and a plurality of blade portions 22. These blade portions 22 are connected around the hub portion 21. Each blade portion 22 has a front face 221 and a back face 222 facing away from each other.

[0069] Please refer to the following: Figures 3 to 6 . Figure 3 for Figure 1 A partially enlarged plan view of the fan blade assembly. Figure 4 for Figure 2 A partially enlarged plan view of the fan blade assembly. Figure 5 for Figure 3 A partially enlarged plan view of the fan blade assembly. Figure 6 for Figure 4 A partially enlarged plan view of the fan blade assembly.

[0070] These first flow guiding structures 30 are disposed on these blade portions 22, for example by injection molding, and include a plurality of first flow guiding bumps 31. These first flow guiding bumps 31 protrude from these front surfaces 221. Each first flow guiding bump 31 has a plurality of first protrusions 311. These second flow guiding structures 40 are disposed on these blade portions 22, for example by injection molding, and include a plurality of second flow guiding bumps 41. These second flow guiding bumps 41 protrude from these back surfaces 222. Each second flow guiding bump 41 has a plurality of second protrusions 411.

[0071] A first microchannel C1 is formed between any two adjacent first protrusions 311, and a second microchannel C2 is formed between any two adjacent second protrusions 411. The first microchannel C1 and the second microchannel C2 are used to guide the airflow generated by the fan blade device 10. Specifically, the first microchannel C1 and the second microchannel C2 are configured, for example, according to the flow angle of the airflow generated by the operation of the fan blade 20. The bottom of the first microchannel C1 and the bottom of the second microchannel C2 are, for example, pointed.

[0072] In this embodiment, each blade portion 22 has a first reference line L1 and a second reference line L2 on its front side 221 and back side 222, respectively. The first reference line L1 extends from the side of the blade portion 22 connected to the hub portion 21 to the side of the blade portion 22 away from the hub portion 21. The angle R1 between the first reference line L1 and the tangent T intersecting the first reference line L1 and the hub portion 21 is, for example, an acute angle. The second reference line L2 extends from the windward side 223 of the blade portion 22 to the leeward side 224 of the blade portion 22. The second reference line L2 is close to the hub portion 21 and is, for example, located at 4 / 5 of the first reference line L1. These first guide bumps 31 are distributed between the side of the blade portion 22 away from the hub portion 21 and the second reference line L2 located on the front side 221. These second guide bumps 41 are distributed between the side of the blade portion 22 away from the hub portion 21 and the second reference line L2 located on the back side 222.

[0073] Furthermore, each blade portion 22 has a third reference line L3 and a fourth reference line L4 on its front side 221 and back side 222, respectively. The third reference line L3 is parallel to the second reference line L2. The fourth reference line L4 is parallel to the first reference line L1. The fourth reference line L4 is close to the leeward side 224 of the blade portion 22 and is located, for example, at 3 / 4 of the distance from the third reference line L3. At least a portion of these first guide bumps 31 are distributed between the leeward side 224 of the blade portion 22 and the fourth reference line L4 on the front side 221. At least a portion of these second guide bumps 41 are distributed between the leeward side 224 of the blade portion 22 and the fourth reference line L4 on the back side 222.

[0074] In this embodiment, the first protrusions 311 include a first sub-protrusion 3111 and two second sub-protrusions 3112. The first sub-protrusion 3111 is located between the two second sub-protrusions 3112. The height of the first sub-protrusion 3111 is, for example, greater than the height of the two second sub-protrusions 3112. The second protrusions 411 include a third sub-protrusion 4111 and two fourth sub-protrusions 4112. The third sub-protrusion 4111 is located between the two fourth sub-protrusions 4112. The height of the third sub-protrusion 4111 is, for example, greater than the height of the two fourth sub-protrusions 4112. The tops of the first sub-protrusion 3111 and the tops of the two second sub-protrusions 3112 are, for example, pointed.

[0075] In this embodiment, the angle R2 between the first sub-protrusion 3111 of each first guide bump 31 and the center line L5 of the front side 221 parallel to the radially extending straight line L6 from the hub portion 21 is, for example, greater than or equal to 10 degrees and less than or equal to 170 degrees. The angle R3 between the third sub-protrusion 4111 of each second guide bump 41 and the center line L7 of the back side 222 parallel to the radially extending straight line L8 from the hub portion 21 is, for example, greater than or equal to 10 degrees and less than or equal to 170 degrees.

[0076] Please refer to the following: Figure 7 . Figure 7 for Figure 1 A cross-sectional schematic diagram of the first guide bump of the fan blade device. Since the structure of these first guide bumps 31 is the same as that of these second guide bumps 41, the following description focuses on one of the first guide bumps 31.

[0077] In this embodiment, the length L of each first flow-guiding bump 31 is, for example, 1.8 mm. The width W of each first flow-guiding bump 31 is, for example, 1.2 mm. Furthermore, the maximum height H1 of the first sub-protrusion 3111 is, for example, 0.6 mm. The maximum height H2 of each second sub-protrusion 3112 is, for example, 0.42 mm. The maximum distance D1 between either the first sub-protrusion 3111 or the two second sub-protrusions 3112 is, for example, 0.45 mm. The maximum distance D2 between the first sub-protrusion 3111 and either of the two first microchannels C1 is, for example, 0.25 mm.

[0078] In this embodiment, the angle R4 between the vertical line L9 connecting the vertex of each first sub-protrusion 3111 to the corresponding front surface 221 and the line L10 connecting the vertex of the first sub-protrusion 3111 to either of the two first microchannels C1 is, for example, 37 degrees. Similarly, the angle (not shown) between the vertical line connecting the vertex of each third sub-protrusion 4111 to the corresponding back surface 222 and the line connecting the vertex of the third sub-protrusion 4111 to either of the two second microchannels C2 is also, for example, 37 degrees.

[0079] In this embodiment, the distance D3 between the first sub-protrusion 3111 of each first guide bump 31 parallel to the center line L11 of the front side 221 and the adjacent first guide bump 31 is, for example, equal and, for example, greater than or equal to the width W of each first guide bump 31. Similarly, the distance (not shown) between the third sub-protrusion 4111 of each second guide bump 41 parallel to the center line of the back side 222 and the adjacent second guide bump 41 is, for example, equal and, for example, greater than or equal to the width of each second guide bump 41.

[0080] Please refer to it again. Figure 1 and Figure 2In this embodiment, the fan blade assembly 10 may further include an outer ring portion 50. The outer ring portion 50 is connected to the side of the blade portions 22 away from the hub portion 21 and surrounds the blade portions 22. By providing the outer ring portion 50, the noise generated when the fan blades 20 are operating can be reduced or the structural strength of the fan blade assembly 10 can be enhanced.

[0081] Please refer to it again. Figure 3 and Figure 5 Since the structures of these first guide protrusions 31 are the same as those of these second guide protrusions 41, the following description will focus on one of the first guide protrusions 31. In this embodiment, when the fan blade 20 rotates and generates airflow, the airflow flows from the windward side 223 of the fan blade 20 along direction A to the first guide protrusion 31. Then, the airflow splits on the side of the first guide protrusion 31 near the windward side 223, and flows along directions B and C respectively in the two first microchannels C1. Next, the airflow converges on the side of the first guide protrusion 31 near the leeward side 224, and flows along direction D to the leeward side 224 of the fan blade 20. In this way, the flow of air guided by the first microchannels C1 can achieve the effect of rectification.

[0082] Please refer to the following: Figures 8 to 13 . Figure 8 This is a schematic diagram of the noise distribution on the front of the fan blades of a comparative fan blade device. Figure 9 This is a schematic diagram of the noise distribution on the front of the fan blade of the fan blade device according to an embodiment of the present invention. Figure 10 This is a schematic diagram of the noise distribution on the reverse side of the fan blades of a comparative fan blade device. Figure 11 This is a schematic diagram of the noise distribution on the reverse side of the fan blade of the fan blade device according to an embodiment of the present invention. Figure 12 This is a schematic diagram of the airflow distribution of the fan blades in a comparative example fan blade device. Figure 13 This is a schematic diagram of the airflow distribution of the fan blades in the fan blade device according to an embodiment of the present invention.

[0083] like Figure 8 , Figure 10 and Figure 12 As shown, in the comparative example of the fan blade device, since the fan blade does not have the first and second flow guiding structures as in this embodiment, when the fan blade operates and generates airflow, airflow vortices will be generated in the high-speed airflow areas A1 and A2 of the fan blade, causing noise to be generated on the windward and leeward sides of the fan blade due to the airflow vortices.

[0084] In this embodiment, as Figure 9 , Figure 11 and Figure 13As shown, since the fan blade 20 of the fan blade device 10 is provided with a first flow guiding structure 30 and a second flow guiding structure 40, the airflow generated by the operation of the fan blade 20 can be adjusted through the first microchannel C1 and the second microchannel C2. Therefore, the airflow can be made smoother, which can significantly reduce the airflow vortices generated in the high-speed airflow areas A1a and A2a on the front and back of the fan blade 20. That is, the airflow is separated from the front and back of the fan blade 20 when the fan blade 20 rotates at high speed, so as to reduce the airflow impact on the fan blade 20. In this way, the noise generated by the operation of the fan blade 20 can be reduced, thereby improving the user experience.

[0085] Furthermore, by providing a first airflow guiding structure 30 and a second airflow guiding structure 40 to the fan blade 20, the noise generated during the operation of the fan blade 20 can be reduced, thereby increasing the rotational speed of the fan blade 20 to generate greater airflow and higher air pressure. In this way, the heat dissipation capacity of the fan blade assembly 10 can be further improved.

[0086] In this embodiment, the first guide bumps 31 are distributed between the side of the blade portion 22 away from the hub portion 21 and the second reference line L2 on the front side 221, and at least some of these first guide bumps 31 are distributed between the leeward side 224 of the blade portion 22 and the fourth reference line L4 on the front side 221. Similarly, the second guide bumps 41 are distributed between the side of the blade portion 22 away from the hub portion 21 and the second reference line L2 on the reverse side 222, and at least some of these second guide bumps 41 are distributed between the leeward side 224 of the blade portion 22 and the fourth reference line L4 on the reverse side 222, but this is not a limitation. In other embodiments, the distribution of these first and second guide bumps can be adjusted according to the shape of the fan blade or the field where the fan blade assembly is applied.

[0087] In this embodiment, the number of first sub-protrusions 3111 of the first protrusions 311 and the number of third sub-protrusions 4111 of the second protrusions 411 are each only one, and the number of second sub-protrusions 3112 of the first protrusions 311 and the number of fourth sub-protrusions 4112 of the second protrusions 411 are each two, but this is not a limitation. In other embodiments, the number of first sub-protrusions of the first protrusions and the number of third sub-protrusions of the second protrusions may each be multiple, and the number of second sub-protrusions of the first protrusions and the number of fourth sub-protrusions of the second protrusions may each be only one or more than three.

[0088] In this embodiment, the height of the first sub-protrusion 3111 is greater than the height of the second sub-protrusion 3112, and the height of the third sub-protrusion 4111 is greater than the height of the fourth sub-protrusion 4112, but this is not a limitation. In other embodiments, the height of the first sub-protrusion may also be equal to the height of the second sub-protrusion, and the height of the third sub-protrusion may also be equal to the height of the fourth sub-protrusion.

[0089] In this embodiment, the bottom of the first microchannel C1, the bottom of the second microchannel C2, the top of the first sub-protrusion 3111, and the top of the second sub-protrusion 3112 are pointed, but this is not a limitation. In other embodiments, the bottom of the first microchannel, the bottom of the second microchannel, the top of the first sub-protrusion, and the top of the second sub-protrusion may also be arc-shaped.

[0090] In this embodiment, the distance D3 between the first sub-protrusion 3111 of each first guide bump 31 parallel to the center line L11 of the front side 221 and the adjacent first guide bump 31 is equal, and the distance between the third sub-protrusion 4111 of each second guide bump 41 parallel to the center line of the back side 222 and the adjacent second guide bump 41 is equal, but not limited thereto. In other embodiments, the distance between the first sub-protrusion of each first guide bump parallel to the center line of the front side and the adjacent first guide bump may be different, and the distance between the third sub-protrusion of each second guide bump parallel to the center line of the back side and the adjacent second guide bump may also be different.

[0091] According to the fan blade device of the above embodiment, since the fan blade is provided with a first flow guiding structure and a second flow guiding structure, the airflow generated by the fan blade operation can be adjusted through the first microchannel and the second microchannel. Therefore, the airflow can be made smoother, thereby significantly reducing the airflow turbulence generated in the high-speed airflow areas on the front and back of the fan blade. In other words, the airflow is separated from the front and back of the fan blade when the fan blade rotates at high speed, thereby reducing the airflow impact on the fan blade. In this way, the noise generated during fan blade operation can be reduced, thus improving the user experience.

[0092] Furthermore, by incorporating a first and a second flow-guiding structure into the fan blades, the noise generated during fan blade operation can be reduced, thereby increasing the fan blade speed to generate greater airflow and higher air pressure. This further enhances the heat dissipation capacity of the fan blade assembly.

[0093] Although the present invention has been disclosed above with reference to the foregoing embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of patent protection of the present invention shall be determined by the scope of protection of the appended claims.

Claims

1. A fan blade device, characterized in that, Include: A blade includes a hub and a plurality of blades connected around the hub, each blade having a front and a back facing opposite each other; and Multiple first flow guiding structures are disposed on the blade portions and include multiple first flow guiding protrusions. These first flow guiding protrusions protrude from the front surfaces, and each of the first flow guiding protrusions has multiple first protrusions. A first microchannel is formed between any two adjacent first protrusions. Multiple second flow guiding structures are disposed on the blade portions and include multiple second flow guiding protrusions. The second flow guiding protrusions protrude from the reverse side, and each of the second flow guiding protrusions has multiple second protrusions. A second microchannel is formed between any two adjacent second protrusions.

2. The fan blade device as described in claim 1, characterized in that, Each of the blade portions has a first reference line and a second reference line on its front and back sides. The first reference line extends from the side where the blade portion is connected to the hub portion to the side of the blade portion away from the hub portion, and the angle between the first reference line and the tangent line intersecting the first reference line and the hub portion is an acute angle. The second reference line extends from the windward side of the blade portion to the leeward side of the blade portion. The second reference line is close to the hub portion and is located at 4 / 5 of the first reference line. The first guide bumps are distributed between the side of the blade portion away from the hub portion and the second reference line on the front side, and the second guide bumps are distributed between the side of the blade portion away from the hub portion and the second reference line on the back side.

3. The fan blade device as described in claim 2, characterized in that, Each of the blade portions has a third reference line and a fourth reference line on its front and back sides, the third reference line being parallel to the second reference line and the fourth reference line being parallel to the first reference line. The fourth reference line is close to the leeward side of the blade portion and is located at 3 / 4 of the third reference line. At least some of the first guide bumps are distributed between the leeward side of the blade portion and the fourth reference line on the front side, and at least some of the second guide bumps are distributed between the leeward side of the blade portion and the fourth reference line on the back side.

4. The fan blade device as described in claim 1, characterized in that, The first protrusions include a first sub-protrusion and two second sub-protrusions, the first sub-protrusion being located between the two second sub-protrusions, and the height of the first sub-protrusion being greater than the height of the two second sub-protrusions. The second protrusions include a third sub-protrusion and two fourth sub-protrusions, the third sub-protrusion being located between the two fourth sub-protrusions, and the height of the third sub-protrusion being greater than the height of the two fourth sub-protrusions.

5. The fan blade device as described in claim 4, characterized in that, The angle between the first sub-protrusion of each of the first guide bumps and the center line parallel to the front side and the straight line extending radially from the hub is greater than or equal to 10 degrees and less than or equal to 170 degrees. The angle between the third sub-protrusion of each of the second guide bumps and the center line parallel to the back side and the straight line extending radially from the hub is greater than or equal to 10 degrees and less than or equal to 170 degrees.

6. The fan blade device as described in claim 4, characterized in that, The maximum height of the first sub-protrusion and the maximum height of the third sub-protrusion are 0.6 mm, the maximum height of each of the two second sub-protrusions and the maximum height of each of the two fourth sub-protrusions are 0.42 mm, the maximum distance between the first sub-protrusion and any of the two second sub-protrusions and the maximum distance between the third sub-protrusion and any of the two fourth sub-protrusions are 0.45 mm, and the maximum distance between the first sub-protrusion and any of the two first microchannels and the maximum distance between the third sub-protrusion and any of the two second microchannels are 0.25 mm.

7. The fan blade device as described in claim 4, characterized in that, The angle between the vertical line connecting the vertex of each of the first sub-protrusions to the corresponding front side and the line connecting the vertex of the first sub-protrusion to either of the two first microchannels is 37 degrees, and the angle between the vertical line connecting the vertex of each of the third sub-protrusions to the corresponding back side and the line connecting the vertex of the third sub-protrusion to either of the two second microchannels is 37 degrees.

8. The fan blade device as claimed in claim 4, characterized in that, The distance between the first sub-protrusion of each of the first guide bumps and the adjacent first guide bump is greater than or equal to the width of each of the first guide bumps, and the distance between the third sub-protrusion of each of the second guide bumps and the adjacent second guide bump is greater than or equal to the width of each of the second guide bumps.

9. The fan blade device as claimed in claim 1, characterized in that, The length of each of the first guide bumps and the length of each of the second guide bumps are 1.8 mm, and the width of each of the first guide bumps and the width of each of the second guide bumps are 1.2 mm.

10. The fan blade device as claimed in claim 1, characterized in that, The fan blade further includes an outer ring portion connected to the side of the blade portions away from the hub portion and surrounding the blade portions inside.

Images