Multi-layer flow dividing type impeller for centrifugal fan

Abstract

According to the multi-layer flow dividing type impeller for the centrifugal fan, each blade is composed of at least three plane or curved surface parts, and transition slope sections exist among the at least three parts; wherein the first part is connected with the second part through a first transition slope section, the second part is connected with the third part through a second transition slope section, the second part is a part protruding relative to a positive pressure surface of the first part, and the third part is a part protruding relative to a negative pressure surface of the second part. Each transition slope section is of a single-stage or multi-stage slope or cambered surface slope section structure, slope slopes K or cambered surface curvatures C between the transition slope sections are not equal, the protruding height of the second part relative to the positive pressure surface of the first part is H, the protruding height of the third part relative to the negative pressure surface of the second part is L, and H is larger than or equal to L. The impeller structure of the centrifugal fan is improved, so that the problems of low adaptability, vibration, noise, stability, quality, low efficiency and the like are solved, and the working condition performance and the operation efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid machinery, in particular to an impeller structure, and more particularly to a multi-layer split-flow impeller for a centrifugal fan. Background Art

[0002] Existing centrifugal fans are generally composed of arc plates or integrally twisted inclined blades, front (upper) cover plates and rear (lower) cover plates. When the centrifugal fan is running, the impeller will produce various vibrations, noises, etc., and the existing fan structure has a large mass, poor stability, poor aerodynamic effect in the impeller, and large gas leakage, which affects life and production efficiency. By designing the impeller structure, the safe operation of the unit can be guaranteed and the operating efficiency of the unit can be improved. It can be seen that it is very necessary to optimize the design of the fan impeller.

[0003] Prior art CN118391301A discloses a centrifugal fan impeller with combined blades, wherein the blades are composed of blade groups; the blade group includes backward curved blades and forward inclined blades, and there are inner blade group guide vanes between the backward curved blades and the forward inclined blades, and there are inter-blade group guide vanes between adjacent blade groups; the inner blade group guide vanes include the first guide vanes in the blade group and the second guide vanes in the blade group, and the first guide vanes in the blade group and the second guide vanes in the blade group are both arc-shaped blades, and the inter-blade group guide vanes include the first guide vanes between the blade groups and the second guide vanes between the blade groups, and the first guide vanes between the blade groups and the second guide vanes between the blade groups are both straight plate blades; the inner blade group guide vanes are located at the outlet of the blade flow channel, and the inter-blade group guide vanes are located at the inlet of the blade flow channel; a first guide vane through hole is provided on the first guide vane in the blade group, and a second guide vane through hole is provided on the second guide vane in the blade group, and the first guide vane through hole and the second guide vane through hole are inclined relative to the same radius line, and the inclination angles are equal; it can improve flow characteristics, reduce noise, and improve conveying efficiency.

[0004] However, the above-mentioned centrifugal fan impeller has design limitations, poor adaptability, and defects in vibration, noise, stability, quality, efficiency, etc. In addition, blade forming is a process of aluminum plate from elastic deformation to plastic deformation. In the blade forming process, when the blade has only one curved surface, its arc surface is relatively large, and the elastic deformation during forming is large. The large elastic deformation makes the rebound distance of the blade large, and there is a large deviation in the shaped arc surface after rebound; therefore, in response to these problems, the applicant proposes a multi-layer split-flow impeller for a centrifugal fan to solve the above-mentioned problems and improve the operating performance and efficiency. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings in the prior art and to propose a multi-layer split flow impeller for a centrifugal fan.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A multi-layer split-flow impeller for a centrifugal fan, wherein the impeller includes an upper cover plate and a lower cover plate, and multiple groups of blades are evenly spaced between the upper cover plate and the lower cover plate, and the blades have a positive pressure surface and a negative pressure surface; characterized in that: the blades are composed of at least three plane or curved surface parts, and there is a transition slope section between at least three parts; wherein the first part is connected to the second part through the first transition slope section, and the second part is connected to the third part through the second transition slope section, the second part is a part protruding relative to the positive pressure surface of the first part, and the third part is a part protruding relative to the negative pressure surface of the second part, and the transition slope section is a single-stage or multi-stage inclined surface or arc surface slope section structure, wherein the inclined surface slope K or arc surface curvature C between each transition slope section is not equal, the protruding height of the second part relative to the positive pressure surface of the first part is H, and the protruding height of the third part relative to the negative pressure surface of the second part is L, wherein H≥L.

[0008] Furthermore, the first transition slope section and the second transition slope section adopt a single-stage inclined slope section structure, wherein the slope K of the first transition slope section is greater than the slope K of the second transition slope section.

[0009] Furthermore, the first transition slope section and the second transition slope section adopt a single-stage cambered slope section structure, wherein the cambered surface curvature C of the first transition slope section is less than the cambered surface curvature C of the second transition slope section.

[0010] Furthermore, the first part is located outside the second part, and the first transition slope section forms a "mouth"-shaped structure.

[0011] Furthermore, the second part is located outside the third part, and the second transition slope section forms a "√"-shaped structure or a "V"-shaped structure.

[0012] Furthermore, the first part is located on one side of the second part, and the first transition slope section forms an "I"-shaped structure or a "│"-shaped structure.

[0013] Furthermore, H=(1.1-2.3)L.

[0014] Furthermore, the first part, the second part and the third part adopt the same bending and torsion blade structure.

[0015] Furthermore, one of the first part and the second part adopts twisted blades, and the other adopts straight blades.

[0016] Furthermore, the blades are welded to the upper cover plate and the lower cover plate in a fish scale pattern.

[0017] Blade forming is the process of aluminum plate from elastic deformation to plastic deformation. In the blade forming process, due to the elasticity of the aluminum plate, when the blade has only one curved surface, its arc surface is relatively large, and the elastic deformation is large during forming. The large elastic deformation makes the rebound distance of the blade large, and there is a large deviation in the shaped arc surface after rebound; a multi-layer split-flow impeller for a centrifugal fan of the present invention, the blade is composed of at least three plane or curved surface parts, and there is a transition slope between at least three parts; wherein the first part is connected to the second part through the first transition slope, and the second part is connected to the third part through the second transition slope, the second part is a part protruding relative to the positive pressure surface of the first part, and the third part is a part protruding relative to the negative pressure surface of the second part, and the transition slope is a single-stage or multi-stage inclined surface or arc surface slope structure, wherein the inclined surface slope K or the arc surface curvature C between each transition slope is not equal, the protruding height of the second part relative to the positive pressure surface of the first part is H, and the protruding height of the third part relative to the negative pressure surface of the second part is L, wherein H≥L. Due to the improvement of the impeller structure of the centrifugal fan and the use of multiple arcs / planes, the blades are bent forward and backward during the forming process, eliminating or reducing the amount of springback, so that the arc surface of the blade after forming has relatively good consistency, thereby obtaining good welding quality, solving the problems of poor adaptability, vibration, noise, stability, quality, low efficiency and other defects, and improving working performance and operating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the centrifugal fan impeller of the present invention;

[0019] Figure 2 It is a schematic diagram of the enlarged structure of the blade cross section;

[0020] Figure 3 It is a simple schematic diagram of another embodiment of a blade composed of a first part, a second part and a third part;

[0021] Figure 4 It is a simple schematic diagram of other embodiments of the first transition slope section and the second transition slope section.

[0022] In the figure: upper cover plate 1, blade 2, lower cover plate 3, positive pressure surface 41, negative pressure surface 42, first part 5, second part 6, third part 7, first transition slope section 8, second transition slope section 9, slope K, camber curvature C, protrusion height H of the second part relative to the positive pressure surface of the first part, protrusion height L of the third part relative to the negative pressure surface of the second part. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0025] like Figure 1-4 As shown, a multi-layer split flow impeller for a centrifugal fan, wherein the impeller comprises an upper cover plate 1 and a lower cover plate 3, a plurality of groups of blades 2 are evenly spaced and arranged between the upper cover plate 1 and the lower cover plate 3, and the blades 2 have a positive pressure surface 41 and a negative pressure surface 42; characterized in that: the blade 2 is composed of at least three plane or curved surface parts, and there is a transition slope section between at least three parts; wherein the first part 5 is connected to the second part 6 through the first transition slope section 8, and the second part 6 is connected to the third part 7 through the second transition slope section 9, the second part 6 is a part protruding relative to the positive pressure surface 41 of the first part 5, and the third part 7 is a part protruding relative to the negative pressure surface of the second part 6, and the transition slope section is a single-stage or multi-stage inclined surface or arc surface slope section structure, wherein the inclined surface slope K or the arc surface curvature C between each transition slope section is not equal, the protruding height of the second part 6 relative to the positive pressure surface of the first part 5 is H, and the protruding height of the third part 7 relative to the negative pressure surface of the second part 6 is L, wherein H≥L.

[0026] Furthermore, the first transition slope section 8 and the second transition slope section 9 adopt a single-stage inclined slope section structure, wherein the slope K of the first transition slope section 8 is greater than the slope K of the second transition slope section 9 .

[0027] Furthermore, the first transition slope section 8 and the second transition slope section 9 adopt a single-stage cambered slope section structure, wherein the cambered surface curvature C of the first transition slope section 8 is less than the cambered surface curvature C of the second transition slope section 9 .

[0028] Furthermore, the first part 5 is located at the periphery of the second part 6, and the first transition slope section 8 forms a "mouth"-shaped structure.

[0029] Furthermore, the second portion 6 is located outside the third portion 7, and the second transition slope section 9 forms a "√"-shaped structure or a "V"-shaped structure.

[0030] Furthermore, the first part 5 is located on one side of the second part 6, and the first transition slope section 8 forms an "I"-shaped structure or a "│"-shaped structure.

[0031] Furthermore, H=(1.1-2.3)L.

[0032] Furthermore, the first part 5, the second part 6 and the third part 7 adopt the same bending and torsion blade structure.

[0033] Furthermore, one of the first part 5 and the second part 6 adopts twisted blades, and the other adopts straight blades.

[0034] Furthermore, the blades 2 are welded to the upper cover plate 1 and the lower cover plate 3 in a fish scale pattern.

[0035] Blade forming is the process of aluminum plate from elastic deformation to plastic deformation. In the blade forming process, due to the elasticity of the aluminum plate, when the blade has only one curved surface, its arc surface is relatively large, and the elastic deformation is large during forming. The large elastic deformation makes the rebound distance of the blade large, and there is a large deviation in the shaped arc surface after rebound; a multi-layer split-flow impeller for a centrifugal fan of the present invention, the blade is composed of at least three plane or curved surface parts, and there is a transition slope between at least three parts; wherein the first part is connected to the second part through the first transition slope, and the second part is connected to the third part through the second transition slope, the second part is a part protruding relative to the positive pressure surface of the first part, and the third part is a part protruding relative to the negative pressure surface of the second part, and the transition slope is a single-stage or multi-stage inclined surface or arc surface slope structure, wherein the inclined surface slope K or the arc surface curvature C between each transition slope is not equal, the protruding height of the second part relative to the positive pressure surface of the first part is H, and the protruding height of the third part relative to the negative pressure surface of the second part is L, wherein H≥L. Due to the improvement of the impeller structure of the centrifugal fan and the use of multiple arcs / planes, the blades are bent forward and backward during the forming process, eliminating or reducing the amount of springback, so that the arc surface of the blade after forming has relatively good consistency, thereby obtaining good welding quality, solving the problems of poor adaptability, vibration, noise, stability, quality, low efficiency and other defects, and improving working performance and operating efficiency.

Claims

1. A multi-layer split-flow impeller for a centrifugal fan, wherein the impeller comprises an upper cover plate (1) and a lower cover plate (3), a plurality of groups of blades (2) are evenly spaced and arranged between the upper cover plate (1) and the lower cover plate (3), and the blades (2) have a positive pressure surface (41) and a negative pressure surface (42); characterized in that: The blade (2) is composed of at least three plane or curved surface parts, and there is a transition slope section between at least three parts; wherein the first part (5) is connected to the second part (6) through a first transition slope section (8), and the second part (6) is connected to the third part (7) through a second transition slope section (9); the second part (6) is a part protruding relative to the positive pressure surface (41) of the first part (5), and the third part (7) is a part protruding relative to the negative pressure surface of the second part (6); the transition slope section is a single-stage or multi-stage inclined surface or arc surface slope section structure, wherein the inclined surface slope K or the arc surface curvature C between each transition slope section is not equal, the protruding height of the second part (6) relative to the positive pressure surface of the first part (5) is H, and the protruding height of the third part (7) relative to the negative pressure surface of the second part (6) is L, wherein H≥L.

2. A multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: The first transition slope section (8) and the second transition slope section (9) adopt a single-stage inclined slope section structure, wherein the slope K of the first transition slope section (8) is greater than the slope K of the second transition slope section (9).

3. A multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: The first transition slope section (8) and the second transition slope section (9) adopt a single-stage arc surface slope section structure, wherein the arc surface curvature C of the first transition slope section (8) is less than the arc surface curvature C of the second transition slope section (9).

4. A multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: The first part (5) is located outside the second part (6), and the first transition slope section (8) forms a "mouth"-shaped structure.

5. The multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: The second part (6) is located outside the third part (7), and the second transition slope section (9) forms a "√"-shaped structure or a "V"-shaped structure.

6. A multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: The first part (5) is located on one side of the second part (6), and the first transition slope section (8) forms a "I"-shaped structure or a "│"-shaped structure.

7. A multi-layer split flow impeller for a centrifugal fan according to claim 1, characterized in that: H=(1.1~2.3)L.

8. A multi-layer split flow impeller for a centrifugal fan according to any one of claims 2 to 5, characterized in that: The first part (5), the second part (6) and the third part (7) adopt the same bending and twisting blade structure.

9. A multi-layer split flow impeller for a centrifugal fan as claimed in claim 6, characterized in that: Among the first part (5) and the second part (6), one of them adopts twisted blades, and the other adopts straight blades.

10. A multi-layer split flow impeller for a centrifugal fan according to any one of claims 1 to 7, characterized in that: The blades (2) are welded to the upper cover plate (1) and the lower cover plate (3) in a fish scale pattern.

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