Fan with two-stage winglet fan blades

Abstract

A fan with two-stage winglet blades is used to solve the problem of noise and fan efficiency reduction caused by the wing end flow of the existing axial fan. It includes a hub, a plurality of blades arranged around the outer periphery of the hub, and a plurality of winglets connected one-to-one with the plurality of blades, each winglet being located at the end of each blade away from the hub, a first fold of each winglet being arranged along the outer edge of each blade and forming a radially outward inclined surface, a second fold of each winglet being arranged along the outer edge of the first fold and forming a radially inward inclined surface, and the fold line at the intersection of each blade and the first fold being a first circular arc, wherein the two ends of the first circular arc are located on the leading edge and the blade surface of each blade, respectively. This can achieve the effects of improving fan efficiency and reducing noise.

Description

Technical Field

[0001] This invention relates to a structure for adjusting aerodynamics, and more particularly to a fan with two-section wingtip blades that improves operating efficiency and reduces noise. Background Technology

[0002] When the blades of an axial fan rotate and drive the airflow, a pressure difference is generated between the upper and lower surfaces of each blade. This causes the air near the blade tip to flow around from the upper surface with higher pressure to the lower surface with lower pressure, thus reducing the pressure difference between the upper and lower surfaces at the blade tip. This weakens the thrust on the air in the terminal area of ​​the fan's outer perimeter. In addition to reducing the overall flow field efficiency of the fan, it can also cause blade instability, wobbling and noise, and even blade wear, thus reducing the fan's lifespan.

[0003] Existing fans can increase the path of airflow from the upper surface of the blade to the lower surface by adding winglets at the blade tips, thereby hindering the airflow around the blade tips. However, the effect of existing winglets in reducing the airflow around the blade tips is limited, especially in medium and large fans where the airflow around the blade tips is more pronounced, leading to more serious noise problems and reduced fan thrust. In addition, medium and large fans use larger motors and hubs, which further reduces the overall flow field efficiency of the fan.

[0004] In view of this, there is indeed a need to improve the existing winglets. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a fan with two-section wingtip blades that can improve fan efficiency.

[0006] A further object of the present invention is to provide a fan with two-section wingtip blades that can reduce the noise of the fan operation.

[0007] Another object of the present invention is to provide a fan with two-stage wingtip blades that can reduce wobbling and thus reduce component losses.

[0008] The directions or similar terms used throughout this invention, such as "front," "back," "top," "bottom," "inner," "outer," and "side," are primarily based on the directions in the accompanying drawings. These directions or similar terms are only used to assist in explaining and understanding the various embodiments of this invention and are not intended to limit the invention.

[0009] The use of the quantifier "a" for elements and components described throughout this invention is for convenience and to provide the general meaning of the scope of the invention; it should be interpreted in this invention as including one or at least one, and the concept of a single one also includes multiple cases, unless it clearly means otherwise.

[0010] The terms "combination," "integration," or "assembly" used throughout this invention mainly refer to forms such as those in which the components can be separated without damaging them after connection, or those in which the components cannot be separated after connection. Those skilled in the art can choose the appropriate term based on the material of the components to be connected or the assembly requirements.

[0011] The present invention discloses a fan with two-segment winglets, comprising: a hub rotatably coupled to a motor stator; a plurality of blades arranged around the periphery of the hub, with one end of each blade connected to the outer periphery of the hub; and a plurality of winglets connected one-to-one to the plurality of blades, each winglet located at the other end of each blade away from the hub, a first fold of each winglet being disposed along the outer edge of each blade and forming a radially outward inclined surface, a second fold of each winglet being disposed along the outer edge of the first fold and forming a radially inward inclined surface, the fold line at the junction of each blade and the first fold being a first arc, wherein the two ends of the first arc are respectively located at the leading edge and the blade surface of each blade; the fold line at the junction of the first fold and the second fold being a second arc, the second fold being away from the outer edge of the hub being a third arc, the two ends of the second arc and the two ends of the third arc being respectively located at the leading edge and the trailing edge of each blade.

[0012] Therefore, the fan with two-section winglets of the present invention can block the airflow that affects the pressure difference on the blade surface by setting two sections of winglets at the end of each blade, and achieve the effect of guiding the airflow, so as to reduce the shaking when the fan is running, and has the effects of improving fan efficiency, reducing noise and reducing blade wear.

[0013] The first arc extends to the trailing edge of each blade, forming a virtual arc that includes the first arc. This virtual arc extends from the leading edge to the trailing edge of each blade. The length of the first arc is greater than or equal to half the length of the virtual arc and less than or equal to two-thirds the length of the virtual arc. Thus, the boundary between the blade and the first fold has a smooth area, while another part is demarcated by the fold line of the first arc, effectively guiding airflow across the blade surface.

[0014] In this design, the distance from the first arc to one axis of the hub is a first radius, the distance from the second arc to the axis is a second radius, and the distance from the third arc to the axis is a third radius. The radial width of the first fold is the second radius minus the first radius, and the radial width of the second fold is the third radius minus the second radius. The ratio of the radial width of the second fold to the radial width of the first fold is greater than or equal to 0.6 and less than or equal to 1.5. This design limits the size of the winglet, allowing the grooves formed by the first and second folds to block airflow and uniformly guide it, thus stabilizing blade rotation and improving fan efficiency.

[0015] In this design, the vertical distance between the highest and lowest points of the first fold is a first height; the vertical distance between the highest and lowest points of the second fold is a second height, and the first height and the second height are equal. Thus, the grooves formed by the winglet can uniformly guide airflow, effectively stabilizing the flow field.

[0016] The axial thickness of the hub is a third height, the first height is greater than or equal to 0.1 times the third height and less than or equal to 0.8 times the third height; and the second height is greater than or equal to 0.1 times the third height and less than or equal to 0.8 times the third height. This limits the proportion of the groove formed by the winglet relative to the fan size, allowing for adjustment of the guided airflow and enabling the selection of the winglet size based on fan characteristics. Attached Figure Description

[0017] Figure 1 : An exploded perspective view of a preferred embodiment of the present invention;

[0018] Figure 2 Top view of a preferred embodiment of the present invention;

[0019] Figure 3 Side view of the fan blades in a preferred embodiment of the present invention;

[0020] Figure 4 :like Figure 3 The enlarged view of the local structure of region A is shown.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1: Little Wing

[0023] 11: First Act

[0024] 12: Second Act

[0025] 2: Blades

[0026] 3: Hub

[0027] F: Fan

[0028] B: Fan blades

[0029] S: Motor stator

[0030] M: Sector frame

[0031] P1: First arc

[0032] P1': Virtual arc

[0033] P2: Second arc

[0034] P3: Third arc

[0035] X: Axis

[0036] r1: First radius

[0037] r2: Second radius

[0038] r3: Third radius

[0039] C: Leading edge

[0040] D: Trailing edge

[0041] G: Rotation direction

[0042] h1: First Height

[0043] h2: Second altitude

[0044] h3: Third altitude. Detailed Implementation

[0045] To make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments of the present invention are described below in detail with reference to the accompanying drawings; in addition, those marked with the same symbols in different drawings are considered to be the same and their descriptions will be omitted.

[0046] Please refer to Figure 1 As shown, this is a preferred embodiment of the fan with two-segment winglets of the present invention. The fan F includes a fan blade B composed of multiple winglets 1, multiple blades 2 and a hub 3, a motor stator S and a fan frame M. One end of the multiple blades 2 is connected to the outer periphery of the hub 3 and arranged in a ring. The other end of each blade 2 is connected to one of the winglets 1. The hub 3 is rotatably connected to the motor stator S and can drive the hub 3 to rotate the multiple blades 2 and the multiple winglets 1 in the space within the fan frame M.

[0047] Please refer to Figure 2 and Figure 3As shown, the plurality of winglets 1 are connected one-to-one to the plurality of blades 2. Each winglet 1 is located at the outermost end of each blade 2. Each winglet 1 includes a first fold 11 and a second fold 12. The first fold 11 is disposed along the outer edge of each blade 2 and forms a radially outward inclined surface; the second fold 12 is disposed along the outer edge of the first fold 11 and forms a radially inward inclined surface, as shown. Figure 3 As shown, each small wing 1 has two opposing inclined surfaces formed by the first fold 11 and the second fold 12, forming a V-shaped or U-shaped groove on the surface of the fan blade B.

[0048] Please refer to again Figure 2 As shown, the fold line at the junction of each blade 2 and the first fold 11 is a first arc P1. The distance from the first arc P1 to one axis X of the hub 3 is a first radius r1. The two ends of the first arc P1 are located at the leading edge C and the blade surface of each blade 2, respectively. That is, the first arc P1 does not extend to the trailing edge D of each blade 2. In addition, the multiple blades 2 rotate in one rotation direction G, so that the leading edge C of each blade 2 faces the airflow and guides the airflow from the leading edge C to the trailing edge D of each blade 2. In detail, if the extension of the first arc P1 to the trailing edge D is a virtual arc P1', and the virtual arc P1' includes the first arc P1, so that the virtual arc P1' extends from the leading edge C to the trailing edge D of each blade 2, then the length of the first arc P1 is preferably greater than or equal to one-half of the length of the virtual arc P1' and less than or equal to two-thirds of the length of the virtual arc P1'. Thus, the boundary between each blade 2 and the first fold 11 has a smooth surface in some areas, while other areas are demarcated by the broken line of the first arc P1.

[0049] Furthermore, the fold line at the junction of the first fold 11 and the second fold 12 is a second circular arc P2, and the distance from the second circular arc P2 to the axis X is a second radius r2; while the outer edge of the second fold 12 away from the axis X is a third circular arc P3, and the distance from the third circular arc P3 to the axis X is a third radius r3. The two ends of the second circular arc P2 and the two ends of the third circular arc P3 are respectively located at the leading edge C and the trailing edge D of each blade 2. Thus, the radial width of the first fold 11 can be the second radius r2 minus the first radius r1, and the radial width of the second fold 12 can be the third radius r3 minus the second radius r2. The ratio of the radial width of the second fold 12 to the first fold 11 is preferably greater than or equal to 0.6 and less than or equal to 1.5, i.e.

[0050] Please refer to Figure 3 and Figure 4As shown, the vertical distance between the highest and lowest points of the first fold 11 is a first height h1; the vertical distance between the highest and lowest points of the second fold 12 is a second height h2, and the first height h1 and the second height h2 are preferably equal. Furthermore, the axial thickness of the hub 3 is a third height h3, where the first height h1 is preferably greater than or equal to 0.1 times the third height h3 and less than or equal to 0.8 times the third height h3; and the second height h2 is preferably greater than or equal to 0.1 times the third height h3 and less than or equal to 0.8 times the third height h3, i.e., h3*0.1≤h1=h2≤h3*0.8.

[0051] Simulation tests were conducted using specific fan blade samples. Compared to fan blades using existing wingtips, fan blades 2 using the two-segment winglet 1 with the two-segment winglet 1 effectively blocked airflow around the wingtip in wind field simulation tests, resulting in smaller pressure changes on the blade surface and achieving a more uniform flow velocity. In addition, under the same operating conditions with a noise level of 49 dB, fan characteristic curve tests were conducted. Using the winglet 1, compared to existing wingtips, increased the maximum flow rate by 2.8% and the maximum static pressure by 6.67%. Furthermore, under the same conditions of 4100 RPM, using the winglet 1 reduced noise by 2.1 dB compared to existing wingtips.

[0052] In summary, the fan with two-section winglets of the present invention can block the airflow that affects the pressure difference on the blade surface by setting two sections of winglets at the end of each blade, and achieve the effect of guiding the airflow, so as to reduce the shaking when the fan is running, and improve the efficiency of the fan and reduce the noise.

[0053] Although the present invention has been disclosed using the above preferred embodiments, it is not intended to limit the present invention. Various modifications and alterations made by those skilled in the art relative to the above embodiments without departing from the spirit and scope of the present invention still fall within the technical scope protected by the present invention. Therefore, the scope of protection of the present invention should be defined by all changes within the meaning and equivalent scope of the claims.

Claims

1. A fan with two-section winglet blades, characterized in that, include: A hub that is rotatably coupled to a motor stator; Multiple blades are arranged around the outer periphery of the hub, and one end of each blade is connected to the outer periphery of the hub; and Multiple winglets are connected one-to-one to the multiple blades. Each winglet is located at the other end of each blade away from the hub. A first fold of each winglet is provided along the outer edge of each blade and forms a radially outward inclined surface. A second fold of each winglet is provided along the outer edge of the first fold and forms a radially inward inclined surface. The fold line at the junction of each blade and the first fold is a first arc, wherein the two ends of the first arc are located at the leading edge and the blade surface of each blade, respectively. The fold line at the junction of the first fold and the second fold is a second arc. The outer edge of the second fold away from the hub is a third arc, and the two ends of the second arc and the three arcs are located at the leading edge and the trailing edge of each blade, respectively.

2. The fan with two-section winglet blades according to claim 1, characterized in that, An arc extending from the first arc to the trailing edge of each blade, including the first arc, is a virtual arc extending from the leading edge to the trailing edge of each blade. The length of the first arc is greater than or equal to one-half the length of the virtual arc and less than or equal to two-thirds the length of the virtual arc.

3. The fan with two-section winglet blades according to claim 1, characterized in that, The distance from the first arc to one axis of the hub is a first radius, the distance from the second arc to the axis is a second radius, the distance from the third arc to the axis is a third radius, the radial width of the first fold is the second radius minus the first radius, the radial width of the second fold is the third radius minus the second radius, and the ratio of the radial width of the second fold to the radial width of the first fold is greater than or equal to 0.6 and less than or equal to 1.

5.

4. The fan with two-section winglet blades according to claim 1, characterized in that, The vertical distance between the highest and lowest points of the first fold is a first height; the vertical distance between the highest and lowest points of the second fold is a second height, and the first height and the second height are equal.

5. The fan with two-section winglet blades according to claim 4, characterized in that, The axial thickness of the hub is a third height, the first height is greater than or equal to 0.1 times the third height and less than or equal to 0.8 times the third height; and the second height is greater than or equal to 0.1 times the third height and less than or equal to 0.8 times the third height.

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