Air supply device and fan

Abstract

The present invention discloses an air supply device and a fan, wherein the air supply device includes a mesh housing, wherein rotatable blades are disposed within the mesh housing; wing ribs are disposed on the suction surface of the blades, extending from the blade tip toward the blade trailing edge, so that the blades deform during operation. The wing ribs can slide relative to the ribs of the mesh housing, thereby maintaining a gap between the blades and the mesh housing through the sliding transition between the wing ribs and the mesh housing. The present invention designs a wing rib on the top and back of the fan blades to optimize the blade shape, increase the fan strength, improve the deformation of the blades during operation, prevent the blades from directly rubbing against the mesh housing, and improve safety performance. This reduces the cost of the air supply device and ensures the optimal installation size of the blades and the mesh housing, effectively preventing an increase in the size of the air supply device.

Description

Technical Field

[0001] The present invention belongs to the field of air supply, and in particular relates to an air supply device and a fan. Background Art

[0002] A fan, also known as a blower, is a household appliance that uses an electric motor to drive the blades to rotate to accelerate the circulation of air. It is mainly used for cooling down and circulating air.

[0003] The current fan mainly consists of three parts: a base, a body and a head. The head is mounted on the base through the body, and the rotating blades on the head accelerate the air flow to achieve a cooling effect.

[0004] However, existing fan air supply devices generally use a combination of thin-film blades and metal mesh covers to achieve air supply through the rotation of the blades. Ordinary axial-flow blades mostly use thin-film continuous smooth curved surface shapes. Generally speaking, the optimal installation distance between the fan blades and the ribs of the rear mesh cover is 30mm. When the speed is high, the blades will produce a certain rotational deformation, the twisting angle becomes larger, the blade deformation during operation is 37mm, and the falling deformation is 60mm. At this time, the fan blades are prone to rubbing against the rear mesh cover. In severe cases, the blades will be inserted into the gaps in the mesh of the mesh cover, causing the blades to break. According to after-sales feedback, this type of fan has certain safety hazards. Summary of the Invention

[0005] The present invention provides an air supply device and a fan to solve the technical problem of interference between fan blades and a rear mesh cover mentioned in the background art.

[0006] To achieve the above objectives, the specific technical solutions of the air supply device and fan of the present invention are as follows:

[0007] A wind supply device includes a mesh cover with a rotatable blade arranged inside the mesh cover; wing ribs are provided on the suction surface of the blade, and the wing ribs extend from the blade tip to the trailing edge of the blade, so that when the blade is deformed during operation, the wing ribs and the ribs of the mesh cover slide relative to each other, so that a gap is maintained between the blade and the mesh cover through the sliding transition between the wing ribs and the mesh cover.

[0008] Furthermore, the ribs form a smooth bow surface at the blade tip, which extends from the blade tip surface to the blade trailing edge, and as the bow surface approaches the blade trailing edge, the bow surface gradually moves away from the blade tip surface, so that the bow angle surface remains flush with the mesh cover.

[0009] Furthermore, a bow angle is formed between the bow surface and the blade surface; the bow angle is 15° to 35°, preferably 18° to 25°.

[0010] Furthermore, the length of the bow surface is 1.3 to 1.5 times the maximum gap of the mesh cover.

[0011] Furthermore, the bow surface is connected to a streamline surface, which extends from the end of the bow surface to the trailing edge of the blade and gradually approaches the blade surface as it approaches the trailing edge of the blade.

[0012] Furthermore, the streamlined surface is rounded with an angle of 2° to 5°.

[0013] Furthermore, the streamline surface is provided with at least two sections, and the streamline surfaces with more than two sections are connected in sequence.

[0014] Furthermore, the length of the wing rib is 1 / 3 to 3 / 4 of the blade tip rotation length, and the width of the wing rib is 2 mm to 4 mm.

[0015] Furthermore, the ribs are arranged along the edge of the blade tip.

[0016] Furthermore, auxiliary ribs are provided on the inner side of the wing ribs, the auxiliary ribs are provided in parallel with the wing ribs, and the auxiliary ribs are radially distributed at equal distances from the blade top to the blade root.

[0017] A fan comprises the above-mentioned air supply device.

[0018] The air supply device and fan of the present invention have the following advantages:

[0019] 1. A rib is designed on the top and back of the fan blade to optimize the blade shape, improve the fan strength, improve the deformation of the blade during operation, prevent the blade from directly rubbing against the mesh cover and break, improve safety performance, reduce the cost of the air supply device, ensure the optimal installation size of the blade and mesh cover, and effectively avoid the increase in the volume of the air supply device.

[0020] 2. Under the premise of ensuring the drop reliability test, the mesh cover is replaced with a plastic mesh cover, which reduces the cost and the weight of the whole machine. When the fan blade is deformed during operation, the wing rib can effectively avoid direct collision and friction between the fan blade and the mesh cover. When severely deformed, the bow angle surface of the wing rib is flush with the mesh cover surface, and the length of the bow angle surface is greater than the gap length of the mesh cover grille. When the fan blade tip collides with the mesh cover, the bow angle surface forms a sliding transition effect, which can effectively prevent the fan blade tip from directly inserting into the mesh cover gap, and plays a role of friction transition.

[0021] 3. The ribs on the suction side of the fan blades effectively clear the airflow over the blade tips during rotation, reducing the noise generated by the interference between the airflow and the blade tips. The optimal distance between the mesh cover and the fan blades does not increase the overall size of the air supply device, achieving a small-volume, highly safe air supply device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the fan of the present invention;

[0023] Figure 2 This is a schematic diagram of the fan blade and mesh cover structure of the present invention;

[0024] Figure 3This is a schematic diagram of the fan blade structure of the present invention;

[0025] Figure 4 for Figure 3 A magnified view of part A;

[0026] Figure 5 This is a numerical schematic diagram of the rib side view of the present invention;

[0027] Figure 6 This is a numerical schematic diagram of the rib of the present invention viewed from above;

[0028] Figure 7 This is a schematic diagram of the mesh cover of the present invention.

[0029] Description of the marks in the figure:

[0030] 1. Base; 2. Fuselage; 3. Front grille; 4. Rear grille; 5. Blade; 51. Hub; 52. Blade; 521. Blade root; 522. Blade tip; 523. Blade tip; 524. Leading edge; 525. Trailing edge; 526. Suction surface; 527. Pressure surface; 6. Wing rib; 61. Bow surface; 611. Bow angle; 62. First streamline surface; 63. Second streamline surface; DETAILED DESCRIPTION

[0031] In order to better understand the purpose, structure and function of the present invention, the air supply device and the fan of the present invention are further described in detail below with reference to the accompanying drawings.

[0032] like Figure 1 As shown, the air supply device of the present invention includes a mesh screen, which is mounted on a base 1 via a body 2. The mesh screen includes a front mesh screen 3 and a rear mesh screen 4, each of which is provided with a plurality of mesh screen ribs distributed around the mesh screen axis. The mesh screen can be made of metal or plastic. Based on drop reliability testing, plastic mesh screens are preferred due to their cost savings and lower processing requirements.

[0033] Combine Figure 2 and Figure 3 As shown, a rotatable fan blade 5 is provided within the mesh housing. The fan blade 5 is driven by a motor to rotate, thereby providing air supply. Specifically, the fan blade 5 includes a hub 51 and a plurality of blades 52 evenly distributed axially along the outer circumference of the hub 51. The root 521 of the blade 52 is connected to the hub 51, and a blade top 522 is formed on the side away from the hub 51. A sharp angle is formed on one side of the blade top 522, which is the blade tip 523. Generally, the ratio of the diameter of the hub 51 of the fan blade 5 to the outer diameter of the fan blade 5 is 0.25 to 0.3, and the blade tip 523 of the fan blade 5 has an angle of 3 to 6 mm.

[0034] Moreover, the fan blade 5 and the mesh cover are coaxially assembled. Due to the central axis assembly method, the center of the blade 52 is kept at the center of the mesh cover. The installation distance T between the fan blade 5 and the rear mesh cover 4 is 30-40 mm.

[0035] As blade 5 rotates, air enters through rear grille 4 and exits through front grille 3. The side of blade 52 closest to rear grille 4 is suction surface 526, while the side closest to front grille 3 is pressure surface 527. Suction surface 526 generates negative pressure, drawing air in from rear grille 4 and pushing it out from front grille 3 via pressure surface 527. Consequently, pressure surface 527 is compressed, causing blade 52 to elastically deform and move closer to rear grille 4. The side of blade 52 where tip 523 is located is leading edge 524, while the side away from tip 523 is trailing edge 525. Leading edge 524 and trailing edge 525 are positioned relative to each other between blade root 521 and blade tip 522, forming a conventional blade 52 with blade root 521, leading edge 524, blade tip 522, and trailing edge 525. As blade 52 rotates, air flows from leading edge 524 to trailing edge 525 (also known as the trailing edge) of blade 5.

[0036] Furthermore, because blade tip 523 is located in front of the rotation direction of blade 52 during the rotation of blade 5, and pressure on pressure surface 527 causes blade 52 to elastically deform and approach rear screen 4, when blade 5 rotates at high speed. Specifically, when blade 5 rotates at high speed, blade 52 is deformed by airflow pressure, resulting in a deformation of 37 mm during operation. If the deformation of the thin-sheet blade 5 is too great, blade tip 523 may directly rub against rear screen 4. In severe cases, blade tip 523 may penetrate into the gaps in the mesh of rear screen 4, causing blade 52 to break. Thus, even with the installation distance T, blade tip 523 may still penetrate into the gaps in rear screen 4 after elastic deformation, causing blade 5 to break, creating a safety hazard of fragments of the blade 5 flying.

[0037] In order to prevent the blade tip 523 from inserting into the gap of the rear mesh cover 4, a wing rib 6 is provided on the suction surface 526 of the blade 52. The wing rib 6 extends from the blade tip 523 to the trailing edge 525 of the blade 52, so that the fan blade 5 is deformed as the blade 52 rotates. The wing rib 6 can slide relative to the ribs of the rear mesh cover 4, so that the friction transition between the wing rib 6 and the mesh cover maintains a gap between the blade 52 and the mesh cover, effectively preventing the blade tip 523 from inserting into the gap of the rear mesh cover 4, and the subsequent damage and splashing of the blade 52.

[0038] To ensure frictional transition between the rib 6 and the grille, the rib 6 forms a smooth bow surface 61 at the blade tip 523. Bow surface 61 extends from the surface of the blade tip 523 toward the trailing edge 525 of the blade 52. As bow surface 61 approaches the trailing edge 525 of the blade 52, it gradually moves away from the surface of the blade tip 523. Simply put, bow surface 61 serves as a guide surface for the starting point of the protrusion of the rib 6. Thus, as the blade 52 rotates, the rib 6 keeps the blade 52 away from the rear grille 4, preventing the edge of the blade 52 from entering the gap in the rear grille 4.

[0039] Therefore, combined Figures 4 to 7As shown, a bow angle 611θ is formed between the bow surface 61 and the surface of the blade 52. The bow angle 611θ is generally 15° to 35°, preferably 18° to 25°. If the bow angle 611 is too large, the ribs 6 may be directly stuck in the gap of the rear mesh 4; if the bow angle 611 is too small, the effect of the ribs 6 can be ignored, which may cause the blade tip 523 to still be directly inserted into the gap of the rear mesh 4. Therefore, the bow angle 611θ is generally between 18° and 25°. Experimental tests have shown that it can effectively prevent the ribs 6 from being inserted into the gap of the rear mesh 4. Specifically, the bow surface 61 can be a circular arc surface with a smaller curvature, or an inclined surface.

[0040] Furthermore, the length of the bow surface 61 should not be too short. Generally, the length of the bow surface 61 should be greater than the gap. However, to be conservative, the length L3 of the bow surface 61 can be greater than the maximum gap Dmax along the outer edge of the rear grille 4. Preferably, the length L3 of the bow surface 61 and the maximum gap Dmax along the outer edge of the rear grille 4 satisfy L3 = 1.3 to 1.5 Dmax. If the length of the bow surface 61 is too short, the bow surface 61 may become stuck in the gap, preventing it from functioning properly.

[0041] To ensure that the rib 6 complies with fluid dynamics, the bow surface 61 is connected to a streamlined surface. The streamlined surface extends from the end of the bow surface 61 toward the trailing edge 525 of the blade 52 and gradually approaches the surface of the blade 52 as it approaches the trailing edge 525. This effectively clears the airflow over the blade tip 522 during rotation and reduces noise generated by interference between the airflow and the blade tip 522.

[0042] Streamline surfaces are preferably streamlined, followed by curved shapes. They can also be straight, but they also need to be smooth to facilitate air flow. Streamline surfaces are generally rounded, with an angle of 2° to 5° being preferred.

[0043] The streamline surface can be set in one section, or two sections or even more sections, and the streamline surfaces of more than two sections are connected in sequence, and the starting end of the next streamline surface is connected to the end of the previous streamline surface. Figure 3 This embodiment uses two choke surfaces as an example. The first choke surface extends from the end of the bow surface 61 toward the trailing edge 525 of the blade 52. The second choke surface extends from the end of the first choke surface toward the trailing edge 525 of the blade 52, with its end contacting the surface of the blade 52. Because the streamline surface must gradually approach the surface of the blade 52 as it approaches the trailing edge 525 of the blade 52, the height H1 of the connection point between the first choke surface and the bow surface 61 is higher than the height H2 of the connection point between the second choke surface and the first choke surface.

[0044] In terms of specific numerical settings, since bow surface 61 has a bow angle 611, the values of bow surface 61 conform to trigonometric functions. The lateral length L1 of bow surface 61 and its length L3 satisfy L1 = L3 * sinθ. The end of the bow length, or its apex, is also the point of connection with the first choke line. Its height H1, together with the lateral length L1 of bow surface 61, satisfies H1 = L1 * tanθ. The lateral distance L2 of the first choke line is 15-30 mm.

[0045] The overall length of the rib 6 is determined by the spiral length of the blade tip 522. The length S of the rib 6 is proportional to the spiral length W of the blade tip 522, satisfying the requirement that S = 1 / 3 to 3 / 4 W. This ensures the aesthetics of the rib 6, optimizes the shape of the blade 52, increases the strength of the blade 5, and mitigates operational deformation of the blade 52. The width d of the rib 6 satisfies the requirement of 2 mm ≤ d ≤ 4 mm.

[0046] The ribs 6 are preferably arranged along the edge of the blade tip 522 to reduce the air resistance of the ribs 6. However, if the ribs 6 are only intended to prevent the blade tip 523 from entering the gap in the mesh, the ribs 6 can be arranged obliquely relative to the edge of the blade tip 522, and the ribs 6 only need to extend from the blade tip 523 to the trailing edge 525 of the blade 52.

[0047] Auxiliary ribs may be provided inside the ribs 6, arranged parallel to the ribs 6. Each blade 52 generally has one to four auxiliary ribs, distributed radially and equidistantly from the tip 522 toward the root 521. Unlike the ribs 6, the auxiliary ribs serve only to strengthen the ribs 6 and prevent damage. They do not rub or slide against the mesh, nor do they cause excessive friction.

[0048] The present invention also discloses a fan, comprising the above-mentioned air supply device. In addition to fans, the fan can also be used on other equipment provided with a mesh cover and a fan blade 5.

[0049] In summary, the present application provides a fan blade 5 and a fan design method thereof, which are mainly used in axial flow fans. The ribs 6 adopt a streamlined design to effectively clear the airflow at the blade top 522 and reduce the interference noise between the airflow and the blade 52. The design method of adding ribs 6 to the suction surface 526 at the tip 523 of the fan blade 5 can prevent the fan blade 5 from rubbing against the rear mesh cover 4 after deformation during operation, thereby improving safety. When the ribs 6 are added to the suction surface 526 of the blade top 522, the collision distance between the blade 52 and the mesh cover can be effectively increased. When the blade 52 is deformed, since the length L3 of the bow length of the ribs 6 and the length S of the ribs 6 are both greater than the maximum gap Dmax of the rear mesh cover 4, the extension direction of the ribs 6 from the blade top 522 to the trailing edge 525 of the fan blade 5 keeps the bow angle 611 of the ribs 6 of the fan blade 5 deformed during operation flush with the rear mesh cover 4, forming a sliding transition. The blade 52 and the rear mesh cover 4 do not directly rub against each other, achieving the effect of excessive friction.

[0050] It will be understood that the present invention is described by way of some embodiments, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. An air supply device, comprising a mesh cover with rotatable blades provided therein; characterized in that: The suction surface of the blade is provided with wing ribs, which extend from the blade tip to the trailing edge of the blade, so that when the blade is deformed during operation, the wing ribs and the ribs of the mesh cover slide relative to each other, so that the gap between the blade and the mesh cover is maintained through the sliding transition between the wing ribs and the mesh cover; The wing rib forms a smooth bow surface at the blade tip, which extends from the blade tip surface to the blade trailing edge, and as the bow surface approaches the blade trailing edge, the bow surface gradually moves away from the blade tip surface; The fan blade includes a hub, and a blade top is formed on a side away from the hub; A bow angle is formed between the bow surface and the blade surface; The extension direction of the ribs from the blade top to the trailing edge keeps the bow surface of the deformed ribs flush with the rear mesh cover surface during the operation of the blade.

2. The air supply device according to claim 1, characterized in that: The bow angle is 15°~35°.

3. The air supply device according to claim 1, characterized in that: The length of the bow surface is 1.3 to 1.5 times the maximum gap of the mesh cover.

4. The air supply device according to claim 1, wherein: The bow surface is connected to a streamline surface, which extends from the end of the bow surface to the trailing edge of the blade and gradually approaches the blade surface as it approaches the trailing edge of the blade.

5. The air supply device according to claim 4, characterized in that: The streamlined surface is rounded with an angle of 2°~5°.

6. The air supply device according to claim 4, characterized in that: The streamline surface is provided with at least two sections, and the streamline surfaces with more than two sections are connected in sequence.

7. The air supply device according to claim 1, characterized in that: The length of the wing rib is 1 / 3 to 3 / 4 of the blade tip chord length, and the width of the wing rib is 2mm to 4mm.

8. The air supply device according to claim 1, wherein: The wing ribs are arranged along the edge of the blade tip.

9. The air supply device according to claim 1, characterized in that: Auxiliary ribs are arranged on the inner side of the wing ribs. The auxiliary ribs are arranged parallel to the wing ribs and are radially distributed at equal distances from the blade top to the blade root.

10. A fan, characterized in that: The invention comprises an air supply device as described in any one of claims 1 to 9.

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