A noise-reducing axial flow fan
By setting up small long wing structures and rounded corner structures on the windward and leeward surfaces of the axial fan blades, the problem of noise increase when increasing the speed of the axial fan is solved, and better noise reduction and heat dissipation effect are achieved.
Patent Information
- Application Number
- CN202421603091.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-08
- Publication Date
- 2025-04-04
- Estimated Expiration
- 2034-07-08
AI Technical Summary
When the axial flow fan increases the speed to achieve better heat dissipation effect, the noise will increase accordingly, resulting in users being easily irritable and physically injured in high-noise environments.
A small long wing structure is set at the tip of the fan blade windward surface, and a rounded corner structure is set at the tip of the leeward surface of the fan blade to suppress the development of the blade tip vortex and reduce the pressure gradient in the wall gap between the fan blade and the fan frame, thereby reducing broadband noise and frequency multiplication vibration.
By setting up a small long wing structure and a rounded corner structure, the wide-frequency noise and frequency-multiplied vibration generated when the fan blade rotates can be effectively reduced, achieving better noise reduction effect and improving heat dissipation effect.
Smart Images
Figure CN222717091U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of heat dissipation fans, and in particular to a noise-reducing axial flow fan. Background Art
[0002] When an axial flow fan is working, the blades push the air to flow in the same direction as the axis, so it is called an axial flow fan. Axial flow fans are ubiquitous in all walks of life.
[0003] An axial flow fan usually includes a fan frame and fan blades, and the fan blades are connected to the fan frame. When the axial flow fan is working, the high-speed rotation of the fan blades will form a tip vortex at the tip of the fan blade, thereby causing broadband noise. At the same time, in the gap between the fan blade and the fan frame, the fluid will have a significant pressure gradient due to the surface friction, thereby increasing the double frequency vibration of the fan blade.
[0004] In order to achieve better heat dissipation effect, the speed of the axial fan is usually increased. However, the increase in the speed of the axial fan will cause a corresponding increase in the noise generated. Users who are in a high-noise environment for a long time are prone to irritability, physical injury and other problems. This problem needs to be solved urgently. Utility Model Content
[0005] In order to achieve better heat dissipation effect and reduce noise at the same time, the present application provides a noise-reducing axial fan.
[0006] The present application provides a noise-reducing axial flow fan, which adopts the following technical solution:
[0007] A noise-reducing axial-flow fan comprises a fan frame and fan blades, wherein the fan blades are rotatably connected to the fan frame, one side of the fan blades is set as a windward side, and the other side of the fan blades is set as a leeward side. A small long wing structure is set at the tip of the windward side of the fan blade, the small long wing structure is set in a long strip shape, and the longitudinal section of the small long wing structure is set in a triangular shape, one side of the small long wing structure is flush with the tip of the fan blade, and the other side of the small long wing structure is set at an inclination with the surface of the windward side of the fan blade.
[0008] By adopting the above technical scheme, when the noise reduction axial flow fan is working, the fan blades rotate at high speed in the fan frame, and a small long wing structure is arranged at the tip of the windward side of the fan blade, which can effectively suppress the development of the tip vortex, thereby reducing the broadband noise generated when the fan blade rotates. While achieving a better heat dissipation effect by increasing the fan blade speed, it can help reduce noise. The small long wing structure is arranged at the main noise concentration area at the tip of the fan blade, which can achieve a better noise reduction effect. At the same time, one side of the small long wing structure is flush with the tip of the fan blade, and the other side of the small long wing structure is inclined to the surface of the windward side of the fan blade, which is beneficial to prevent wind diffusion, thereby helping to further improve the heat dissipation effect of the noise reduction axial flow fan.
[0009] Preferably, a chamfered structure is provided at the tip position of the leeward side of the fan blade, and the chamfered structure is provided along the length direction of the tip of the fan blade.
[0010] By adopting the above technical solution, when the fan blades rotate at high speed in the fan frame, setting a chamfered structure at the tip position of the leeward side of the fan blade can reduce the pressure gradient at the wall gap between the fan blade and the fan frame, thereby helping to reduce the double-frequency vibration of the fan blade, and further helping to reduce noise.
[0011] Preferably, the heights of both ends of the small long wing structure gradually decrease, and the thicknesses of both ends of the small long wing structure gradually decrease.
[0012] By adopting the above technical solution, this structure reduces the fluid separation and turbulence at the tip of the windward side of the fan blade, which is beneficial to improving the fluidity of the airflow and at the same time reduces the generation of turbulent noise, so that the entire noise-reducing axial fan can operate more smoothly and quietly.
[0013] Preferably, the height range of the middle position of the small long wing structure is set to 1mm-3mm.
[0014] By adopting the above technical solution, the height of the middle position of the small long wing structure is set within this range without affecting the heat dissipation effect, while ensuring the effectiveness of the noise reduction effect.
[0015] Preferably, the angle formed by the two side edges of the small long wing structure is set to range from 30° to 60°.
[0016] By adopting the above technical solution, the angle formed by the two side edges of the small long wing structure is set within this range, which is beneficial to reducing the broadband noise of the axial flow fan while ensuring the lightness of the fan blades.
[0017] Preferably, the width of the rounded corner structure gradually decreases from the middle to both sides.
[0018] By adopting the above technical solution, this arrangement can further reduce the pressure gradient at the wall gap between the fan blade and the fan frame, thereby facilitating further reduction of the harmonic vibration.
[0019] Preferably, the fan blades are curved in an arc shape.
[0020] By adopting the above technical solution, this setting can optimize the fan efficiency and air flow of the axial fan, can better guide the wind flow, increase the air volume and wind pressure, and thus achieve better heat dissipation effect.
[0021] Preferably, a connecting structure is provided between the fan blades and the fan frame, and the fan blades are rotatably connected to the fan frame via the connecting structure.
[0022] By adopting the above technical solution, the fan blades are rotatably connected to the fan frame through the connecting structure, thereby realizing the operation of the noise-reducing axial flow fan.
[0023] In summary, the present application includes at least one of the following beneficial technical effects:
[0024] 1. By arranging a small long wing structure at the tip of the windward side of the fan blade, when the noise reduction axial flow fan is working, the fan blade rotates at high speed in the fan frame, and the small long wing structure can effectively suppress the development of the tip vortex, thereby reducing the broadband noise generated when the fan blade rotates. While achieving a better heat dissipation effect by increasing the fan blade speed, it can help reduce noise. The small long wing structure is arranged at the main noise concentration area at the tip of the fan blade, which can achieve a better noise reduction effect. At the same time, one side of the small long wing structure is flush with the tip of the fan blade, and the other side of the small long wing structure is inclined to the surface of the windward side of the fan blade, which is beneficial to prevent wind diffusion, thereby helping to further improve the heat dissipation effect of the noise reduction axial flow fan.
[0025] 2. By setting a chamfered corner structure at the tip of the leeward side of the fan blade, when the fan blade rotates at high speed in the fan frame, the chamfered corner structure can reduce the pressure gradient at the wall gap between the fan blade and the fan frame, which is beneficial to reduce the double-frequency vibration of the fan blade, and further help to reduce noise.
[0026] 3. The height at both ends of the small long wing structure gradually decreases, and the thickness at both ends of the small long wing structure gradually decreases, which reduces the fluid separation and turbulence at the tip of the windward side of the fan blade, which is beneficial to improving the fluidity of the airflow and reducing the generation of turbulent noise, so that the entire noise-reducing axial fan can work more smoothly and quietly. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a schematic diagram of the overall structure of the noise reduction axial flow fan in an embodiment of the present application.
[0028] Figure 2 It is an exploded view of the noise reduction axial flow fan in the embodiment of the present application.
[0029] Figure 3 It is a schematic diagram of the structure of the windward surface of the fan blade in the embodiment of the present application.
[0030] Figure 4 yes Figure 3 Enlarged view of part A in the middle.
[0031] Figure 5 It is a schematic diagram of the structure of the leeward side of the fan blade in an embodiment of the present application.
[0032] Figure 6 yes Figure 5 Enlarged view of part B in the middle.
[0033] Figure 7 It is a vertical cross-sectional schematic diagram of the noise reduction axial flow fan in an embodiment of the present application.
[0034] Figure 8 yes Figure 7 Enlarged view of part C in the middle.
[0035] Description of reference numerals:
[0036] 1. Fan frame; 2. Fan blades; 3. Small long wing structure; 4. Rounded corner structure; 5. Connection structure; 51. Motor housing; 52. Stator; 53. Bearing; 54. Magnetic strip; 55. PCB control board; 56. Retaining ring; 57. Spring. DETAILED DESCRIPTION
[0037] The following is combined with Figure 1-8 This application is described in further detail.
[0038] Existing axial flow fans usually include a fan frame and fan blades, and the fan blades are rotatably connected to the fan frame. When the axial flow fan is working, the high-speed rotation of the fan blades will form a tip vortex at the tip of the fan blade, thereby causing broadband noise. At the same time, in the wall gap between the fan blade and the fan frame, the fluid will receive a significant pressure gradient due to the surface friction, thereby increasing the double frequency vibration of the fan blade. This is the main reason for the noise generated by the axial flow fan. In order to achieve a better heat dissipation effect of the axial flow fan, the general practice is to increase the speed of the axial flow fan. However, the increase in the speed of the axial flow fan will increase the broadband noise and double frequency vibration accordingly, resulting in a corresponding increase in the noise generated. Users who are in a high-noise environment for a long time are prone to irritability, physical injury and other problems.
[0039] In order to solve the above problems, the present application embodiment discloses a noise-reducing axial flow fan. Figure 1 , including a fan frame 1 and a fan blade 2, the fan blade 2 is rotatably connected to the fan frame 1, and the fan blade 2 is curved in an arc shape to optimize the fan efficiency and air flow of the axial flow fan, so as to better guide the wind flow, increase the wind volume and wind pressure, and thus achieve a better heat dissipation effect. At the same time, a connecting structure 5 is provided between the fan blade 2 and the fan frame 1, and the fan blade 2 is rotatably connected to the fan frame 1 through the connecting structure 5. Referring to Figure 2 The connection structure 5 includes a motor housing 51, a stator 52, a bearing 53, a magnetic strip 54, a PCB control board 55, a retaining ring 56 and a spring 57. The motor housing 51, the stator 52, the bearing 53, the magnetic strip 54, the PCB control board 55, the retaining ring 56 and the spring 57 are assembled together so that the fan blades 2 can rotate in the fan frame 1 through electromagnetic induction. This is a conventional connection structure 5 in the axial flow fan and will not be described in detail here.
[0040] Reference Figure 3 and Figure 4One side of the fan blade 2 is set as the windward surface, and a small long wing structure 3 is set at the tip of the windward surface of the fan blade 2. The small long wing structure 3 is set in a long strip shape along the length direction of the edge at the tip, and the longitudinal section of the small long wing structure 3 is set in a triangular shape. One side of the small long wing structure 3 is flush with the tip of the fan blade 2, and the other side of the small long wing structure 3 is inclined to the surface of the windward surface of the fan blade 2. When the noise reduction axial flow fan is working, the fan blade 2 rotates at a high speed in the fan frame 1, and the small long wing structure 3 at the tip of the windward surface of the fan blade 2 can effectively suppress the development of the tip vortex, thereby reducing the broadband noise generated when the fan blade 2 rotates, and can help reduce noise while achieving a better heat dissipation effect by increasing the rotation speed of the fan blade 2. In addition, the small long wing structure 3 is arranged at the main noise concentration area at the tip of the fan blade 2, which can achieve a better noise reduction effect. At the same time, one side of the small long wing structure 3 is flush with the tip of the fan blade 2, and the other side of the small long wing structure 3 is inclined to the surface of the windward side of the fan blade 2, so that the wind direction is more concentrated, which is beneficial to prevent wind diffusion, thereby helping to further improve the heat dissipation effect of the noise reduction axial flow fan.
[0041] Reference Figure 4 , the height of both ends of the small long wing structure 3 gradually decreases, and the thickness of both ends of the small long wing structure 3 gradually decreases, so as to reduce the fluid separation and turbulence at the tip of the windward side of the fan blade 2, which is beneficial to improve the fluidity of the airflow, and at the same time reduce the generation of turbulent noise, so that the entire noise reduction axial flow fan can work more smoothly and quietly. It should be noted that the height range of the middle position of the small long wing structure 3 is set to 1mm-3mm, and the angle range formed by the two sides of the small long wing structure 3 is set to 30°-60°. The height of the middle position of the small long wing structure 3 is set in this range to match the angle range formed by the two sides of the small long wing structure 3. While not affecting the heat dissipation effect, it can ensure the effectiveness of the noise reduction effect and the lightness of the fan blade 2.
[0042] Reference Figure 5 and Figure 6 The other side of the fan blade 2 is set as the leeward side, and the tip position of the leeward side of the fan blade 2 is provided with a rounded structure 4, and the rounded structure 4 is arranged along the length direction of the edge at the tip of the fan blade 2. Figure 7 and Figure 8 When the fan blade 2 rotates at high speed in the fan frame 1, the rounded corner structure 4 can reduce the pressure gradient at the wall gap between the fan blade 2 and the fan frame 1, which is beneficial to reduce the double frequency vibration of the fan blade 2, and further help to reduce the noise. It should be noted that the width of the rounded corner structure 4 gradually decreases from the middle to both sides to further reduce the pressure gradient at the wall gap between the fan blade 2 and the fan frame 1, which is beneficial to further reduce the double frequency vibration. In actual tests, the fan blade double frequency vibration noise can be reduced by 2-6dB.
[0043] The implementation principle of a noise-reducing axial flow fan in an embodiment of the present application is as follows: when the rotation speed of the blade 2 of the axial flow fan is increased in order to achieve a better heat dissipation effect, the small long wing structure 3 at the tip of the windward side of the blade 2 can effectively suppress the development of the tip vortex, thereby reducing the broadband noise generated when the blade 2 rotates. While achieving a better heat dissipation effect by increasing the rotation speed of the blade 2, it can also help reduce noise. The small long wing structure 3 is arranged at the main noise concentration area at the tip of the blade 2, which can achieve a better noise reduction effect. At the same time, the small long wing structure 3 is helpful in preventing wind diffusion, thereby helping to further improve the heat dissipation effect of the noise-reducing axial flow fan. The rounded corner structure 4 at the tip position of the leeward side of the blade 2 can reduce the pressure gradient at the wall gap between the blade 2 and the fan frame 1, thereby helping to reduce the harmonic vibration of the blade 2, and further helping to reduce noise.
[0044] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A noise-reducing axial flow fan, comprising a fan frame (1) and fan blades (2), wherein the fan blades (2) are rotatably connected to the fan frame (1), and characterized in that: One side of the fan blade (2) is arranged as a windward side, and the other side of the fan blade (2) is arranged as a leeward side. A small long wing structure (3) is arranged at the tip of the windward side of the fan blade (2). The small long wing structure (3) is arranged in a long strip shape, and the longitudinal section of the small long wing structure (3) is arranged in a triangular shape. One side of the small long wing structure (3) is flush with the tip of the fan blade (2), and the other side of the small long wing structure (3) is arranged at an angle to the surface of the windward side of the fan blade (2).
2. The noise-reducing axial flow fan according to claim 1, characterized in that: A rounded corner structure (4) is provided at the tip of the leeward side of the fan blade (2), and the rounded corner structure (4) is provided along the length direction of the tip of the fan blade (2).
3. The noise-reducing axial flow fan according to claim 1, characterized in that: The heights of both ends of the small long wing structure (3) gradually decrease, and the thicknesses of both ends of the small long wing structure (3) gradually decrease.
4. The noise-reducing axial flow fan according to claim 1, characterized in that: The height range of the middle position of the small long wing structure (3) is set to be 1mm-3mm.
5. The noise-reducing axial flow fan according to claim 1, characterized in that: The angle formed by the two side edges of the small long wing structure (3) is set to range from 30° to 60°.
6. The noise-reducing axial flow fan according to claim 2, characterized in that: The width of the rounded corner structure (4) gradually decreases from the middle to both sides.
7. The noise-reducing axial flow fan according to claim 1, characterized in that: The fan blades (2) are arranged to be curved in an arc shape.
8. The noise-reducing axial flow fan according to claim 1, characterized in that: A connecting structure (5) is provided between the fan blade (2) and the fan frame (1), and the fan blade (2) is rotatably connected to the fan frame (1) via the connecting structure (5).