Fan impeller of ternary twisted blades, and fan

Abstract

A fan impeller of ternary twisted blades (3), and a fan. The fan impeller comprises: a plurality of blades (3), which are arranged around an axis of rotation of the impeller; a top plate (1); and a bottom plate (2), which are integrally formed, wherein the blades (3) are located between the top plate (1) and the bottom plate (2); an air inlet is provided in the middle of the top plate (1), an air outlet is formed between the top plate (1) and the bottom plate (2), one surface of each blade (3) faces the axis of rotation of the impeller, and the other surface of each blade (3) faces away from the axis of rotation of the impeller; each blade (3) comprises a front half region close to the axis of rotation of the impeller and a rear half region (35) away from the axis of rotation of the impeller; the front half region comprises an upper front half region (33) close to the top plate (1) and a lower front half region (34) close to the bottom plate (2); the upper front half region (33) protrudes and bends towards the direction of the axis of rotation of the impeller so as to form a curved surface; the lower front half region (34) protrudes and bends in the direction away from the axis of rotation of the impeller so as to form a curved surface; and the rear half region (35) protrudes and bends in the direction away from the axis of rotation of the impeller so as to form a curved surface.

Description

A fan impeller and blower with three-dimensional twisted blades Technical Field

[0001] The present invention belongs to the technical field of fans, and in particular relates to a fan impeller with three-dimensional twisted blades and a fan. Background Art

[0002] The gas flow within a backward-flowing centrifugal fan is a complex three-dimensional viscous flow, riddled with secondary and separated flows, making flow control difficult. A three-dimensional design that can maximize the matching of the fan's internal three-dimensional flow with the fan's structure can effectively reduce losses and improve fan efficiency.

[0003] Among existing product types, centrifugal impellers are known to be made from a variety of materials, such as metal sheets of uniform thickness, hollow profiles, and plastic impellers reinforced with glass fiber. The plastic impeller process can achieve a variety of complex blade shapes while maintaining a low impeller cost, offering advantages in blade twist and thickness distribution. With the advancement of fan design technology, improvements in material properties, and injection molding processes, plastic impellers have a high degree of curvature. Complex three-dimensional twisted blades can improve the fan's static pressure efficiency while reducing operating noise through excellent gas flow control technology.

[0004] Adding glass fiber can significantly increase the strength of plastic impellers. However, due to the difficulty of product quality control in actual production, the structural strength of impeller products often fluctuates within a certain range, and sufficient safety margins must be ensured in the impeller design. Therefore, it is necessary to propose a new three-dimensional twisted blade structure to improve structural strength and enhance fan performance.

[0005] Summary of the Invention

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide a fan impeller and blower with three-dimensional twisted blades, improve the blade structure, and achieve the goals of high efficiency, wide operating conditions and low noise of the blower.

[0007] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0008] In the first aspect of the present invention, the present invention proposes a fan impeller with three-dimensional twisted blades, comprising an integrally formed top plate, a bottom plate and a plurality of blades arranged around the impeller rotation axis, the blades being located between the top and the bottom plates, an air inlet being arranged in the middle of the top plate, an air outlet being formed between the top plate and the bottom plate, the bottom end of the blade being connected to the bottom plate, the top end of the blade being connected to the top plate, one side of the blade facing the impeller rotation axis, and the other side of the blade facing away from the impeller rotation axis.

[0009] The blade includes an integrally formed front half region close to the impeller rotation axis and a rear half region away from the impeller rotation axis, wherein the front half region includes a front upper half region close to the top plate and a front lower half region close to the bottom plate, wherein the front upper half region is convexly curved in a direction toward the impeller rotation axis to form a curved surface, and the front lower half region is convexly curved in a direction away from the impeller rotation axis to form a curved surface, the leading edge of the front half region presents an S-shaped curve, the rear half region is convexly curved in a direction away from the impeller rotation axis to form a curved surface, and the trailing edge of the rear half region presents a C-shaped curve. This special blade shape can optimize the inlet velocity distribution and improve the impeller's flow capacity, thereby increasing the impeller's aerodynamic efficiency and achieving the goals of high efficiency, wide operating conditions, and low noise for the fan.

[0010] Preferably, the convex curvature of the front upper region is smaller than that of the rear half region, and the convex curvature of the front lower region is smaller than that of the rear half region.

[0011] Preferably, along the length of the leaf, the length of the front upper half region accounts for 20 to 70% of the length of the leaf, more preferably, the length of the front upper half region accounts for 40 to 60% of the length of the leaf; along the length of the leaf, the length of the front lower half region accounts for 20 to 70% of the length of the leaf, more preferably, the length of the front lower half region accounts for 40 to 60% of the length of the leaf.

[0012] Preferably, along the blade height direction, the height of the front upper half region accounts for 30-70% of the blade height, and the height of the front lower half region accounts for 30-70% of the blade height.

[0013] Preferably, the ratio of the radial length of the top end of the leading edge of the blade from the impeller rotation axis to the radial length of the bottom end of the leading edge of the blade from the impeller rotation axis is 1.5 to 1.9, more preferably, the ratio of the radial length of the top end of the leading edge of the blade from the impeller rotation axis to the radial length of the bottom end of the leading edge of the blade from the impeller rotation axis is 1.6 to 1.7, more preferably, the ratio of the radial length of the top end of the leading edge of the blade from the impeller rotation axis to the radial length of the bottom end of the leading edge of the blade from the impeller rotation axis is 1.66.

[0014] Preferably, the top plate includes a straight portion forming the impeller air inlet and an arc portion close to the outer edge of the impeller, the straight portion is parallel to the impeller rotation axis, and the arc portion is a curved surface, wherein the angle between the tangent of the inner wall profile of the arc portion and the impeller rotation axis is β1, and the range of β1 is 90° to 150°, and more preferably, 120°≤β1≤150°.

[0015] Preferably, the bottom plate protrudes toward the top plate, and a mounting groove is formed on a side of the bottom plate away from the top plate.

[0016] More preferably, along the radial direction of the bottom plate, the inner wall profile of the outer edge of the bottom plate bends toward and approaches the impeller rotation axis, and the angle between the tangent of the inner wall profile of the outer edge of the bottom plate and the impeller rotation axis is β2, β2≤90°.

[0017] Preferably, there is a gap R between the trailing edge of the blade and the maximum outer circle of the bottom plate in the radial direction of the bottom plate, and R is equal to the outer circle diameter D of the bottom plate. 2hub The ratio of R to the outer diameter D of the bottom plate (2) is greater than or equal to 0.05. More preferably, R is greater than or equal to the outer diameter D of the bottom plate (2). 2hub The ratio is 0.10~0.16.

[0018] In a second aspect of the present invention, the present invention provides a fan comprising the above-mentioned fan impeller. Beneficial effects:

[0019] The present invention has a special double S-shaped curved structure on the blade as a whole, and the structural strength is improved, so that the impeller design has sufficient margin in terms of safety. Moreover, the special double S-shaped curved structure of the blade of the present invention also has the effect of improving the performance and efficiency of the fan. The S-shaped curved design of the front half of the blade can control and reduce the airflow separation at the fan inlet, making the airflow velocity distribution inside the flow channel of the fan impeller more uniform. Compared with the fan with a conventional leading edge design, the blade of the present invention can optimize the inlet velocity distribution, while improving the impeller's flow capacity, increasing the impeller's aerodynamic efficiency. Combined with the special C-shaped design of the back half of the area and the curved surface optimization of the entire blade surface, the purpose of high efficiency, wide operating conditions and low noise of the fan is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 shows an overall schematic diagram of the present invention;

[0021] FIG2 is a partial schematic diagram of a fan impeller according to the present invention;

[0022] Figure 3 is a schematic diagram of a blade;

[0023] FIG4 is a schematic diagram of the blade at another angle;

[0024] FIG5 is a schematic cross-sectional view of a fan impeller;

[0025] FIG6 shows a schematic diagram of the connection between the fan impeller and the motor;

[0026] FIG7 shows a schematic diagram of the connection between the fan impeller and the motor;

[0027] FIG8 is a schematic diagram showing a blade formed by stacking five stream surface profiles along a stacking line;

[0028] FIG9 is a schematic diagram showing the leading edge vertices of five stream surface airfoils forming multiple angles with the starting position in the circumferential direction;

[0029] FIG10 is a schematic diagram showing the plurality of angles formed between the trailing edge vertices of the five stream surface airfoil profiles and the starting position in the circumferential direction;

[0030] FIG11 is a schematic diagram of a conventional impeller;

[0031] FIG12 is a performance characteristic curve diagram of the embodiment and the comparative example.

[0032] Figure numbers: 1-top plate, 2-bottom plate, 3-blade, 4-reinforcement structure, 5-motor, 6-conventional impeller; 11-straight part, 12-arc part, 21-mounting slot; 31-leading edge, 32-trailing edge, 33-front upper half area, 34-front lower half area, 35-rear half area. DETAILED DESCRIPTION

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other embodiments can be obtained based on these drawings without inventive work.

[0034] As shown in Figures 1-12, the present invention provides a fan impeller with three-dimensional twisted blades 3, comprising an integrally formed top plate 1, a bottom plate 2, and a plurality of blades 3 arranged around the impeller's rotation axis. The blades 3 are located between the top plate 1 and the bottom plate 2. The top plate 1 has an overall ring-like structure. The middle of the top plate 1 is an air inlet, and an air outlet is formed between the top plate 1 and the bottom plate 2. The bottom end of the blade 3 is connected to the bottom plate 2, and the top end of the blade 3 is connected to the top plate 1. One side of the blade 3 faces the impeller's rotation axis, and the other side of the blade 3 faces away from the impeller's rotation axis.

[0035] As shown in FIG1 , the blade 3 includes an integrally formed front half region near the impeller rotation axis and a rear half region 35 away from the impeller rotation axis. The front half region further includes a front upper half region 33 near the top plate 1 and a front lower half region 34 near the bottom plate 2. It is easy to understand that the front upper half region 33, the front lower half region 34, and the rear half region 35 constitute a complete impeller. The front upper half region 33 is convexly curved in a direction toward the impeller rotation axis to form a curved surface, the front lower half region 34 is convexly curved in a direction away from the impeller rotation axis to form a curved surface, and the rear half region 35 is convexly curved in a direction away from the impeller rotation axis to form a curved surface. As can be seen from FIG1-4 , the outer side of the rear half region 35, i.e., the trailing edge 32, exhibits a C-shaped curve, while the inner side of the entire front half region, i.e., the leading edge 31, exhibits an S-shaped curve. In addition, when observing the front half region of the blade 3 from different angles, its leading edge 31 can exhibit two different shapes of S-shaped curves. This special double S-shaped curved structure is beneficial for improving the structural strength of the blade 3 and providing sufficient margin for safety in the impeller design. Moreover, the special double S-shaped curved structure of the blade 3 of the present invention also has the effect of improving the performance and efficiency of the fan. The S-shaped curved design of the front half of the blade 3 can control and reduce the airflow separation at the fan inlet, making the airflow velocity distribution inside the flow channel of the fan impeller more uniform. Compared with the fan of conventional design, the blade 3 of the present invention can optimize the inlet velocity distribution, while improving the impeller's flow capacity, increasing the impeller's aerodynamic efficiency. Combined with the special C-shaped design of the rear half area 35 and the surface optimization of the entire blade 3 surface, the purpose of high efficiency, wide operating conditions and low noise of the fan is achieved.

[0036] For ease of description, in the present invention, one side of the front half area close to the impeller rotation axis is the leading edge 31, and one side of the rear half area 35 away from the impeller rotation axis is the trailing edge 32. It is easy to understand that one side of the front upper area 33 close to the impeller rotation axis and one side of the front lower area 34 close to the impeller rotation axis naturally transition to form the leading edge 31. The direction from the leading edge 31 to the trailing edge 32 is the length direction of the blade 3, that is, the blade length direction, such as the L direction in Figure 2. The direction from the top end of the blade 3 to the bottom end of the blade 3 is the height direction of the blade 3, that is, the blade height direction, such as the H direction in Figure 2.

[0037] In the present invention, the blade 3 is formed by stacking multiple stream surface profiles along the blade height direction according to the stacking line, wherein the stream surface profile is a two-dimensional blade profile in the M-Theta space and is expressed as a three-dimensional space curve in the Cartesian coordinate system.

[0038] In the present invention, the convex curvature of the front upper region 33 is less than that of the rear region 35, and the convex curvature of the front lower region 34 is less than that of the rear region 35. The inlet side of the blade 3 of the present invention adopts a special-shaped curved structure to reduce airflow separation at the fan inlet, optimize the inlet velocity distribution, and improve the impeller's flow capacity. The outlet side of the blade 3 adopts a more curved surface to improve fan efficiency.

[0039] As shown in Figures 8-10, the ratio of the radial length from the top of the leading edge 31 of the blade 3 to the radial length from the bottom of the leading edge 31 of the blade 3 to the impeller's rotation axis is 1.5 to 1.9. More preferably, the ratio is 1.6 to 1.7, and more preferably, the ratio is 1.66. This allows the gas velocity distribution within the impeller to better match the geometric surface of the blade 3, resulting in better flow control. As can be seen from Figures 1-2, the blade 3 as a whole also tilts outward from the bottom plate 2 to the top plate 1.

[0040] More specifically, along the blade length direction, the length of the front upper region 33 accounts for 20 to 70% of the length of the blade 3 . Preferably, the length of the front upper region 33 accounts for 40 to 60% of the length of the blade 3 .

[0041] More specifically, along the length direction of the blade, the length of the front lower half region 34 accounts for 20 to 70% of the length of the blade 3 . Preferably, the length of the front lower half region 34 accounts for 40 to 60% of the length of the blade 3 .

[0042] It is easy to understand that along the length direction of the leaf, the ratio of the length of the rear half area 35 to the length of the blade 3 is adjusted according to the ratio of the length of the front upper area 33 and the front lower area 34 to the length of the blade 3, and there is no limitation here.

[0043] More specifically, along the blade height, the height of the front upper region 33 accounts for 30-70% of the blade 3's height, and the height of the front lower region 34 accounts for 30-70% of the blade 3's height. That is, the front upper region 33 and / or the front lower region 34 must have sufficient area, and the front upper region 33 and the front lower region 34 must have distinct curved surfaces. More preferably, along the blade height, the height of the front upper region 33 accounts for 40% of the blade 3's height, and the height of the front lower region 34 accounts for 60% of the blade 3's height.

[0044] It is easy to understand that the front upper area 33 , the front lower area 34 and the rear area 35 transition naturally and smoothly.

[0045] In the present invention, the top plate 1 includes a straight portion 11 forming the impeller air inlet and a curved portion 12 near the outer edge of the impeller. As shown in FIG5 , the straight portion 11 is parallel to the impeller rotation axis, and the curved portion 12 is a curved surface, wherein the angle between the tangent of the inner wall profile of the curved portion 12 and the impeller rotation axis is β1, and the range of β1 is 90° to 150°. Preferably, 120°≤β1≤150°. At this time, the curved portion 12 bends to form a hook shape, and the outlet of the curved portion 12 bends toward the impeller air outlet. The top end of the blade 3 is connected to the curved portion 12 of the top plate 1. For ease of processing and manufacturing, the connection between the blade 3 and the top plate 1 can be close to the straight portion 11 of the top plate 1.

[0046] In the present invention, the bottom plate 2 has a conical structure, as shown in Figures 5 and 6. The bottom plate 2 protrudes toward the top plate 1, and a mounting groove 21 is formed on the side of the bottom plate 2 away from the top plate 1, which is connected to the motor 5. The bottom plate 2 and the motor 5 are connected to form an impeller hub structure.

[0047] Along the radial direction of the bottom plate 2, the inner wall profile of the outer edge of the bottom plate 2 bends and approaches the impeller rotation axis, i.e., the RA direction in the figure, and the angle between the tangent of the inner wall profile of the outer edge of the bottom plate 2 and the impeller rotation axis is β2, β2 is a right angle or an acute angle, i.e., β2≤90°, preferably, 30°≤β2≤60°, and more preferably, β2=38°.

[0048] Furthermore, there is a gap R between the trailing edge 32 of the blade 3 and the maximum outer circle of the bottom plate 2 in the radial direction of the bottom plate 2, and R is equal to the outer diameter D of the bottom plate 2. 2hub The ratio of R to D is greater than or equal to 0.05. 2hub The ratio of R to D is 0.05 to 0.25, more preferably, 2hub The ratio is 0.10 to 0.15, that is, R / D 2hub >0.05, especially 0.05≤R / D 2hub ≤0.25, the better solution is 0.10≤R / D 2hub ≤0.16, more preferably, R / D 2hub =0.151.

[0049] When both β1 and β2 are acute angles, the top plate 1 and bottom plate 2 form a trumpet-shaped design at the impeller outlet. This design is beneficial for controlling the separation vortex near the suction surface of the top plate 1 and blades 3, improving the fan's aerodynamic efficiency and reducing noise. This trumpet-shaped design is also beneficial in the manufacturing process of plastic one-piece molded impellers, especially for demolding from injection molds.

[0050] The blades 3 are connected to the top plate 1 and the bottom plate 2 with a reinforcing structure 4, which is a rounded design. This design can greatly enhance the structural strength of the connection between the top plate 1, the bottom plate 2 and the blades 3, thereby improving the safety of the fan. It is easy to understand that the impeller of the present invention is suitable for plastic integral molding. In addition, the impeller of the present invention can also be made of metal, especially by splitting the sheet metal and then assembling it to form an impeller.

[0051] It should be noted that the front upper area 33 of the blade 3 protrudes in the direction toward the impeller's axis of rotation to form a curved surface, and the top edge of the front upper area 33 of the blade 3 is connected to the arc portion 12 of the top plate 1. Therefore, a connection area with a larger angle is formed between the top edge of the blade 3 and the top plate 1, namely point A in Figure 1. This design can also be beneficial to the split processing of the fan impeller, and the connection strength in this connection area is also improved.

[0052] In the present invention, the impeller is designed as a centrifugal or mixed flow impeller, and the top plate 1 and the bottom plate 2 of the impeller completely cover the axial outer edge portion of the blade 3. The impeller of the present invention is a closed impeller design.

[0053] Furthermore, the number of blades 3 in the impeller is 4 to 16, and preferably, the number of blades 3 is 5 to 7.

[0054] The following is combined with Figures 8-10 to assist in explaining a more specific design of the present invention. In the present invention, the blade 3 is composed of five flow surface blade profiles stacked along the blade height direction according to the stacking line. From bottom to top along the blade height direction, it is easy to understand that the fifth flow surface blade profile at the top and the first flow surface blade profile at the bottom are equivalent to the top and bottom surfaces of the blade 3, the third flow surface blade profile is at the transition point between the front upper region 33 and the front lower region 34, the second flow surface blade profile is at the position with the greatest protrusion in the front lower region 34, and the fourth flow surface blade profile is at the position with the greatest protrusion in the front upper region 33.

[0055] The leading edge vertices of the five stream surface blades are Le1, Le2, Le3, Le4 and Le5, and the trailing edge vertices are Tra1, Tra2, Tra3, Tra4 and Tra5. As shown in Figures 9-10, the leading edge vertices of the five stream surface blades form multiple angles α1, α2, α3, α4 and α5 with the starting position in the circumferential direction, and the trailing edge vertices of the five stream surface blades form multiple angles α6, α7, α8, α9 and α10 with the starting position in the circumferential direction. The leading edge vertices of the stream surface blades are aligned with the impeller rotation axis. The distance between the top and bottom of the blade 3 inlet is the leading edge diameter of the blade 3, the distance between the trailing edge vertex of the stream surface blade profile and the impeller rotation axis is the trailing edge diameter of the blade 3 inlet, the leading edge diameters of the blade 3 inlet of the five stream surface blade profiles are D1, D2, D3, D4 and D5, and the trailing edge diameters of the blade 3 inlet of the five stream surface blade profiles are D6, D7, D8, D9 and D10, among which, D5>D4>D3>D2>D1, D10>D9>D8>D7>D6, α5>α4>α3>α1>α2, α10>α9>α6>α8>α7.

[0056] From the size relationship among α1, α2, α3, α4 and α5, as well as the size relationship among D1, D2, D3, D4 and D5, it can be seen from the side that the area of ​​the leading edge 31 of the blade 3 close to the bottom plate 2, that is, the inner side of the front lower half area 34, protrudes in the direction away from the impeller rotation axis, while the area of ​​the leading edge 31 of the blade 3 close to the top plate 1, that is, the inner side of the front upper half area 33, protrudes in the direction toward the impeller rotation axis, and the leading edge 31 part of the blade 3 is S-shaped.

[0057] From the size relationship between α6, α7, α8, α9 and α10 and the size relationship between D6, D7, D8, D9 and D10, it can be seen from the side that the middle part of the trailing edge 32 in the axial position protrudes in the direction away from the impeller rotation axis, and the rear half area 35 of the blade 3 is generally C-shaped.

[0058] When D5 / D1=1.5-1.9, the gas velocity distribution in the impeller is more matched with the geometric surface of the blade 3, and the flow control becomes better. Preferably, D5 / D1=1.6-1.7, and more preferably, D5 / D1=1.66.

[0059] When α2≤α1<α3 and (α5-α4)<(α4-α3), the increasing trend of the leading edge vertex angle at the top of the blade 3 is reduced, and the leading edge vertex of the blade 3 will show an S-shaped distribution in the circumferential direction.

[0060] The angle between the leading edge 31 and the trailing edge 32 of each stream surface airfoil is called the wrap angle, which affects the chord length of the blade 3.

[0061] The wrap angle of the Le1-Tra1 flow surface blade is △αm, △αm=α6-α1, the range of △αm can be 60~80°, preferably, the range of △αm is 65~75°, and more preferably, △αm=71.5°.

[0062] The wrap angle △αn of the Le2-Tra2 flow surface blade is △αn=α7-α2, wherein the range of △αn can be 60~80°, preferably, the range of △αn is 65~75°, and more preferably, △αn=69.8°.

[0063] The wrap angle △αk of the Le3-Tra3 flow surface blade is △αk=α8-α3, wherein the range of △αk can be 60~80°, preferably, the range of △αk is 60~65°, and more preferably, △αk=64.5°.

[0064] The wrap angle △αl of the Le4-Tra4 flow surface blade is △αl = α9-α4, wherein the range of △αl can be 55 to 80°, preferably, the range of △αl is 55 to 65°, and more preferably, △αl = 58°.

[0065] The wrap angle △αu of the Le5-Tra5 flow surface blade is △αu=α10-α5, wherein the range of △αu can be 60~80°, preferably, the range of △αu is 60~65°, and more preferably, △αu=63.9°.

[0066] The technical solution of the present invention is described in detail below with reference to specific embodiments.

[0067] Embodiment: The fan of this embodiment adopts the fan impeller of the present invention.

[0068] Comparative Example: The fan of this comparative example adopts a conventional impeller 6, the shape of which is shown in FIG11 . The blades as a whole protrude in a direction away from the rotation axis, and both the inner and outer edges of the blades are C-shaped curved.

[0069] The performance characteristic curves of the embodiment and the comparative example are shown in FIG12 .

[0070] As shown in Figure 12, compared with the conventional front-end design fan, the improved blade 3 of the present invention presents a special twisted shape in the front half of the blade 3 inlet, which can better balance the relationship between the blade 3 inlet diameter and the blade 3 inlet angle, optimize the inlet velocity distribution, and improve the flow capacity of the impeller. The present invention increases the aerodynamic efficiency of the impeller, and combines the surface optimization of the entire blade profile to achieve a high-efficiency, wide-operating-condition, and low-noise optimized design of the fan. In particular, the design goal of the fan requires improving the regional performance of low static pressure and large flow conditions. The embodiment of the present invention produces a larger air volume under the same volume while maintaining ultra-high efficiency.

[0071] The embodiments provided by the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A fan impeller with a ternary twisted blade, Characterized in that, It includes an integrally formed top plate (1), a bottom plate (2), and a plurality of blades (3) arranged around the rotation axis of the impeller. The blades (3) are located between the top and the bottom plate (2). An air inlet is provided in the middle of the top plate (1), and an air outlet is formed between the top plate (1) and the bottom plate (2). The bottom end of the blade (3) is connected to the bottom plate (2), the top end of the blade (3) is connected to the top plate (1), one side of the blade (3) faces the rotation axis of the impeller, and the other side of the blade (3) faces away from the rotation axis of the impeller; The blade (3) includes an integrally formed front half region close to the rotation axis of the impeller and a rear half region (35) far from the rotation axis of the impeller. The front half region includes a front upper half region (33) close to the top plate (1) and a front lower half region (34) close to the bottom plate (2). Among them, the front upper half region (33) bulges and bends in the direction towards the rotation axis of the impeller to form a curved surface, the front lower half region (34) bulges and bends in the direction away from the rotation axis of the impeller to form a curved surface, the leading edge of the front half region presents an S-shaped bend, the rear half region (35) bulges and bends in the direction away from the rotation axis of the impeller to form a curved surface, and the trailing edge of the rear half region (35) presents a C-shaped bend.

2. The fan impeller according to claim 1, Characterized in that, The degree of convex bending of the front upper half region (33) is less than that of the rear half region (35), and the degree of convex bending of the front lower half region (34) is less than that of the rear half region (35).

3. The fan impeller according to claim 1 or 2, Characterized in that, Along the blade length direction, the length of the front upper half region (33) accounts for 20 - 70% of the length of the blade (3); along the blade length direction, the length of the front lower half region (34) accounts for 20 - 70% of the length of the blade (3).

4. The fan impeller according to claim 1 or 2, Characterized in that, Along the blade height direction, the height of the front upper half region (33) accounts for 30 - 70% of the height of the blade (3), and the height of the front lower half region (34) accounts for 30 - 70% of the height of the blade (3).

5. The fan impeller according to claim 1 or 2, Characterized in that, The ratio of the radial length from the top end of the leading edge (31) of the blade (3) to the rotation axis of the impeller to the radial length from the bottom end of the leading edge (31) of the blade (3) to the rotation axis of the impeller is 1.5 - 1.

9.

6. The fan impeller according to claim 1, Characterized in that, The top plate (1) includes a straight part (11) forming the air inlet of the impeller and an arc part (12) close to the outer edge of the impeller. The straight part (11) is parallel to the rotation axis of the impeller, and the arc part (12) is an arc surface.

7. The fan impeller according to claim 6, Characterized in that, The included angle between the tangent of the inner wall profile line of the arc part (12) and the rotation axis of the impeller is β1, and the range of β1 is 90° - 150°.

8. The fan impeller according to claim 1, Characterized in that, The bottom plate (2) protrudes towards the top plate (1), and an installation groove (21) is formed on the side of the bottom plate (2) away from the top plate (1). Along the radial direction of the bottom plate (2), the inner wall profile of the outer edge of the bottom plate (2) bends and approaches towards the impeller rotation axis direction, and the included angle between the tangent of the inner wall profile of the outer edge of the bottom plate (2) and the impeller rotation axis is β2, where β2 ≤ 90°.

9. The fan impeller according to claim 1 or 8, characterized in that There is a gap R between the trailing edge (32) of the blade (3) and the maximum outer circle of the bottom plate (2) in the radial direction of the bottom plate (2), and the ratio of R to the outer circle diameter D of the bottom plate (2) is greater than or equal to 0.

05. 2hub ​ 10. The fan impeller according to claim 9, characterized in that The ratio of R to the outer diameter D of the bottom plate (2) 2hub is 0.10 to 0.

16.

11. A blower, characterized in that it includes the fan impeller according to any one of claims 1 - 10.

Images