Air guide panel for centrifugal fan and centrifugal fan

Abstract

The invention relates to the field of centrifugal fans, in particular to an air guide panel for a centrifugal fan and the centrifugal fan. The air guide panel for the centrifugal fan is located at an axial air outlet of the centrifugal fan, the centrifugal fan comprises a motor and an impeller, and the motor is connected with the impeller to drive the impeller to rotate. The air guide panel for the centrifugal fan comprises an air guide part and a panel part which are integrally formed; the impeller is coaxially connected with a wind gathering part, the end part, far away from the panel part, of the wind guide part is used for coaxially extending into the wind gathering part, and a gap is formed between the end part and the peripheral wall of the wind gathering part; a motor body of the motor is provided with a plurality of supporting rods, the circular track where the supporting rods are located is coaxial with the impeller, the panel part is provided with mounting holes in one-to-one correspondence with the supporting rods, and the circular track where all the mounting holes are located is coaxial with the air guide part. The concentricity of the air guide part and the impeller can be improved, the gap between the air gathering part and the air guide part can be small enough, the fan efficiency is improved, and vibration and noise are reduced.

Description

Technical Field

[0001] The invention relates to the field of centrifugal fans, and in particular to an air guide panel for a centrifugal fan and a centrifugal fan. Background Art

[0002] Axial outlet centrifugal fans are widely used in ventilation, dust removal, industrial gas transportation and other scenarios because of their advantages such as the airflow direction is consistent with the equipment axis and easy pipe docking. However, the air shroud and mounting panel of existing axial outlet centrifugal fans usually adopt a split structure. The air shroud and mounting panel are independent components and are generally fixed by bolts. Due to the limitations of processing accuracy, human adjustment errors during assembly, and component deformation, the position deviations of each connection point are gradually added up during the assembly process, which ultimately leads to a large concentricity deviation between the inner wall of the air shroud and the impeller.

[0003] In axial-discharge centrifugal fans, in order to ensure the balance of air pressure inside and outside the air shroud and suppress the vibration and noise caused by the impact of gas on the rigid structure, a gap is usually left between the air shroud and the wind gathering part of the impeller. Due to the large concentricity deviation between the inner wall of the air shroud and the impeller, the following problems may occur:

[0004] First, the gap between the wind collecting part and the wind guide cover of the impeller is uneven, forming local vortices, which leads to a decrease in aerodynamic performance and reduces the efficiency of the fan;

[0005] Secondly, in order to avoid the air flow being blocked due to the small local gap and the vibration and collision between the air guide cover and the air collecting part, the gap between the air collecting part of the air guide cover and the air collecting part of the impeller cannot be made small enough in consideration of the concentricity deviation, which causes more gas to be lost from the gap, further reducing the efficiency of the fan.

[0006] Third, eccentricity destroys the dynamic balance of the rotor, causing high-frequency vibration and aerodynamic noise. The vibration and noise of the fan are still relatively large during operation.

[0007] Therefore, it is urgent to solve the above technical problems. Summary of the invention

[0008] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an air guide panel for a centrifugal fan, which can improve the concentricity of the air guide part and the impeller, so that the gap between the wind collecting part and the air guide part can be made small enough, thereby improving the efficiency of the fan and reducing vibration and noise.

[0009] In order to solve the above technical problems, the technical solution of the present invention is: an air guide panel for a centrifugal fan, located at the axial air outlet of the centrifugal fan, the centrifugal fan comprises a motor and an impeller, the motor is connected to the impeller to drive the impeller to rotate;

[0010] An air guide panel for a centrifugal fan comprises an air guide portion and a panel portion which are integrally formed;

[0011] The impeller is coaxially connected to the wind collecting portion, and the end of the wind guiding portion away from the panel portion is used to coaxially extend into the wind collecting portion and is separated from the peripheral wall of the wind collecting portion by a gap;

[0012] The motor body is equipped with a plurality of support rods, the circular tracks where the support rods are located are coaxial with the impeller, the panel portion is provided with mounting holes corresponding to the support rods one by one, and the circular tracks where all the mounting holes are located are coaxial with the air guide portion.

[0013] Furthermore, the inner diameter of at least a portion of the wind collecting portion decreases along the wind outlet direction, and the inner diameter of at least a portion of the wind guiding portion increases along the wind outlet direction.

[0014] Furthermore, the reduction speed of the inner diameter reduction portion of the wind gathering portion along the wind outlet direction gradually decreases;

[0015] The increasing speed of the inner diameter increasing portion of the air guiding portion along the air outlet direction gradually increases.

[0016] In order to further make the gap have the same width along the air outlet direction to ensure smooth air outlet at the gap, the parts of the air guide portion and the air collection portion that overlap in the axial direction are parallel to each other.

[0017] Furthermore, the width W of the gap is 3-4 mm.

[0018] In order to make the panel part as thin as possible and have sufficient strength, a bending part extending in the circumferential direction is provided in the middle part of the panel part, and the circular trajectory where all the mounting holes are located is closer to the outer edge of the panel part than the bending part.

[0019] In order to further shift the center of mass of the air guide panel toward the motor side to reduce the lever arm, the bent portion is inclined from the inside to the outside toward the motor side in the radial direction of the air guide portion.

[0020] In order to further enhance the strength of the position where the panel part is connected to the support rod, the area where each mounting hole is located is recorded as a mounting area, and each mounting area is bent and protruded in a direction away from the air guide part; wherein,

[0021] The support rod is threadedly connected with the nut after passing through the mounting hole, and the mounting area completely covers the bottom surface of the nut.

[0022] In order to further increase the strength of the entire air guide portion, each installation area forms an integral plane with a portion of the panel portion located inside the bent portion through a reinforcement portion that is bent and protrudes in a direction away from the air guide portion.

[0023] The present invention also relates to a centrifugal fan, comprising an air guide panel for the centrifugal fan.

[0024] After adopting the above technical solution, the present invention designs the air guide part and the panel part into an integrally formed structure. The concentricity between the two and the concentricity between the circular trajectory where all the mounting holes are located and the air guide part are guaranteed by the mold. The concentricity can be very high, avoiding the assembly error caused by the traditional split structure. Since the concentricity between the circular trajectory where all the mounting holes are located and the air guide part can be very high, and the circular trajectory where several support rods are located is coaxial with the impeller, after the support rods and the mounting holes are assembled, the concentricity between the air guide part and the impeller and between the air collecting part coaxially connected to the impeller can be very high. Therefore, the uniformity of the gap between the air guide part and the air collecting part in the circumferential direction can be ensured, avoiding the reduction of the fan efficiency due to the formation of local vortices; it can also avoid high-frequency vibration and aerodynamic noise caused by the destruction of the dynamic balance of the rotor, reducing the working noise of the fan. In addition, since the gap between the air guide part and the air collecting part is ensured to be uniform in the circumferential direction, the width W of the gap can be very small, 3-4mm, while balancing the pressure inside and outside the air guide part, reducing gas loss as much as possible and improving the efficiency of the fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of an air guide panel for a centrifugal fan of the present invention installed on the centrifugal fan;

[0026] Figure 2 for Figure 1 A structural diagram from another perspective;

[0027] Figure 3 for Figure 1 A cross-sectional view of

[0028] Figure 4 for Figure 3 A magnified view of part A;

[0029] Figure 5 It is a structural schematic diagram of an air guide panel for a centrifugal fan of the present invention;

[0030] Figure 6 for Figure 5 A cross-sectional view of

[0031] Figure 7 for Figure 6 A magnified view of part B;

[0032] In the figure, 10, motor; 20, impeller; 30, wind collecting part; 40, support rod; 50, nut; 60, base; 1, air guide part; 2, panel part; 21, mounting hole; 22, bending part; 23, mounting area; 24, reinforcement part; 3, gap. DETAILED DESCRIPTION

[0033] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0034] like Figures 1 to 7 As shown, an air guide panel for a centrifugal fan is located at the axial air outlet of the centrifugal fan. The centrifugal fan includes a motor 10 and an impeller 20. The motor 10 is connected to the impeller 20 to drive the impeller 20 to rotate;

[0035] The air guide panel for a centrifugal fan comprises an air guide portion 1 and a panel portion 2 which are integrally formed;

[0036] The impeller 20 is coaxially connected to the wind collecting portion 30, and the end of the wind guide portion 1 away from the panel portion 2 is used to coaxially extend into the wind collecting portion 30, and there is a gap 3 between the end and the peripheral wall of the wind collecting portion 30;

[0037] The motor 10 is provided with a plurality of support rods 40 , the circular tracks of which are coaxial with the impeller 20 , the panel 2 is provided with mounting holes 21 corresponding to the support rods 40 , and the circular tracks of which are coaxial with the air guide 1 .

[0038] Specifically, in this embodiment, the air guide part 1 and the panel part 2 are designed to be an integrally formed structure, and the concentricity between the two and the concentricity between the circular trajectory where all the mounting holes 21 are located and the air guide part 1 are ensured by the mold, and the concentricity can be very high, avoiding the assembly error caused by the traditional split structure. Since the concentricity between the circular trajectory where all the mounting holes 21 are located and the air guide part 1 can be very high, and the circular trajectory where a number of support rods 40 are located is coaxial with the impeller 20, after the support rods 40 and the mounting holes 21 are assembled, the air guide part 1 and the impeller 20 and the air collecting part 30 coaxially connected to the impeller 20 can achieve very high concentricity, which can ensure the uniformity of the gap between the air guide part 1 and the air collecting part 30 in the circumferential direction, avoiding the reduction of the fan efficiency due to the formation of local vortices; it can also avoid high-frequency vibration and aerodynamic noise caused by the destruction of the dynamic balance of the rotor, and reduce the working noise of the fan. Furthermore, since the circumferential uniformity of the gap 3 between the air guide portion 1 and the air collecting portion 30 is ensured, the gap 3 can be made very small (the width of the gap 3 in the structure mentioned in the background technology is 6 mm, and the width W of the gap 3 in the structure in this embodiment is 3-4 mm). While balancing the internal and external pressures of the air guide portion 1, the gas loss is reduced as much as possible, thereby improving the efficiency of the fan.

[0039] Among them, Figure 1 and Figure 2 In the illustrated example, there are four support rods 40 , but the present invention is not limited thereto.

[0040] In one embodiment, Figures 1 to 6 As shown, the inner diameter of at least a portion of the wind collecting portion 30 decreases along the wind outlet direction, and the inner diameter of at least a portion of the wind guiding portion 1 increases along the wind outlet direction.

[0041] Preferably, the speed of decreasing the inner diameter of the air collecting portion 30 along the air outlet direction gradually decreases, and the speed of increasing the inner diameter of the air guiding portion 1 along the air outlet direction gradually increases. That is, the cross-sections of the air collecting portion 30 and the air guiding portion 1 along the axial direction are both concave arcs, which can guide the gas well.

[0042] More preferably, the overlapped parts of the air guide 1 and the air collection part 30 in the axial direction are parallel to each other. In this way, the uniformity of the gap 3 in the gas flow direction can be ensured, the pressure inside and outside the air guide 1 can be better balanced, and the gas can be further ensured to be discharged smoothly from the gap 3. The minimum gap 3 that can be achieved is the thickness of the entire gap 3, ensuring that the entire gap 3 is kept at a relatively small size to minimize gas loss.

[0043] In one embodiment, Figure 1 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, a bending portion 22 extending in the circumferential direction is provided in the middle portion of the panel portion 2 , and the circular tracks where all the mounting holes 21 are located are closer to the outer edge of the panel portion 2 than the bending portion 22 .

[0044] In this way, the panel part 2 can still have high strength and rigidity in a relatively thin condition. The thickness of the conventional panel part 2 is 4-5 mm to meet the strength requirement, while the panel thickness of the present embodiment is 2.5 mm to meet the strength requirement. In addition, when the thickness of the panel part 2 is reduced, its weight can be reduced, thereby reducing the cost.

[0045] In one embodiment, Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the bent portion 22 is inclined from the inside to the outside toward the motor 10 in the radial direction of the air guide portion 1 .

[0046] In this way, the center of mass of the entire panel part 2 can be moved toward the motor 10 side, reducing the lever arm. While meeting the dimensional requirements of the entire air guide panel in the gas flow direction, the weight is reduced and the lever arm is reduced. This can well ensure the stability of the position of the entire air guide panel, avoid the position of the air guide panel from shifting after long-term use, ensure the concentricity of the air guide part 1 and the impeller 20 and the wind focusing part 30 for a long time, and also reduce the requirements for the supporting strength of the support rod 40, thereby further reducing the weight of the centrifugal fan.

[0047] In one embodiment, Figure 1 and Figure 5 As shown, the area where each mounting hole 21 is located is recorded as a mounting area 23, and each mounting area 23 is bent and protruded toward a direction away from the air guide portion 1; wherein,

[0048] The support rod 40 passes through the mounting hole 21 and is threadedly connected to the nut 50 , and the mounting area 23 completely covers the bottom surface of the nut 50 .

[0049] In this way, the strength of the portion of the panel portion 2 that cooperates with the support rod 40 can be improved, and the pressure at the portion where the panel portion 2 contacts the nut 50 can be reduced.

[0050] exist Figure 1 and Figure 5 In the structure shown, the mounting area 23 is triangular in shape, and each mounting area 23 faces a corner of the directional panel portion 2 .

[0051] In one embodiment, each installation area 23 forms an integral plane with a portion of the panel portion 2 located inside the bent portion 22 by means of a reinforcement portion 24 that is bent and protrudes in a direction away from the air guide portion 1 .

[0052] Specifically, by connecting the bent areas, the strength of the entire panel portion 2 can be further improved, and the difficulty of processing can be reduced.

[0053] like Figure 1 , Figure 2 and Figure 3 As shown, a centrifugal fan includes an air guide panel for a centrifugal fan in any of the above embodiments.

[0054] The following is a detailed introduction to the air guide panel and the centrifugal fan with respect to the working process of the air guide panel including all the above-mentioned features in the centrifugal fan.

[0055] After each support rod 40 is passed through the corresponding mounting hole 21 and the nut 50 is screwed, the assembly of the air guide panel on the axial air outlet centrifugal fan is realized. The air guide part 1 and the panel part 2 adopt an integrated molding structure, which eliminates the trouble of bolting the two and the assembly error, and can well ensure the concentricity through the mold. Therefore, when the circular trajectory where the impeller 20, the air gathering part 30 and each support rod 40 are located remains coaxial, the concentricity of the air guide part 1 and the impeller 20 and the air gathering part 30 can be well guaranteed, and the uniformity of the gap between the air guide part 1 and the air gathering part in the circumferential direction can be guaranteed, so as to avoid the reduction of the fan efficiency due to the formation of local vortex, and also avoid the high-frequency vibration and aerodynamic noise caused by the destruction of the dynamic balance of the rotor, thereby reducing the working noise of the fan. In addition, since the uniformity of the gap between the air guide part 1 and the air gathering part in the circumferential direction is guaranteed, the gap can be made very small, and while balancing the internal and external pressures of the air guide part 1, the gas loss can be reduced as much as possible, thereby improving the fan efficiency.

[0056] In addition, the axially overlapping parts of the air guide portion 1 and the air collecting portion 30 are parallel to each other, which can ensure the uniformity of the gap 3 in the gas flow direction, better balance the internal and external pressures of the air guide portion 1, and further ensure smooth discharge of gas from the gap 3. The minimum gap 3 that can be achieved is the thickness of the overall gap 3, ensuring that the overall gap 3 is maintained at a relatively small size to minimize gas loss.

[0057] In addition, a bending portion is provided in the middle position of the panel portion 2, which extends in the circumferential direction and is inclined from the inside to the outside toward the motor 10 in the radial direction of the air guide portion 1. When the thickness of the panel portion 2 is reduced, its strength can still be guaranteed, and the center of mass is moved inward, and the lever arm is reduced. That is, the weight is reduced and the lever arm is reduced while meeting the dimensional requirements of the entire air guide panel in the gas flow direction. The two can work together to ensure the stability of the position of the entire air guide panel, avoid the position shift of the air guide panel after long-term use, ensure the concentricity of the air guide portion 1 and the impeller 20 and the wind collecting portion 30 for a long time, maintain the high efficiency and low noise of the centrifugal fan for a long time, and can also reduce the requirements for the supporting strength of the support rod 40, thereby further reducing the weight of the centrifugal fan.

[0058] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An air guide panel for a centrifugal fan, located at an axial air outlet of the centrifugal fan, wherein the centrifugal fan comprises a motor (10) and an impeller (20), wherein the motor (10) is connected to the impeller (20) to drive the impeller (20) to rotate; characterized in that: An air guide panel for a centrifugal fan comprises an air guide portion (1) and a panel portion (2) formed in one piece; The impeller (20) is coaxially connected to a wind collecting portion (30); an end of the wind guide portion (1) away from the panel portion (2) is used to coaxially extend into the wind collecting portion (30) and is separated from a peripheral wall of the wind collecting portion (30) by a gap (3); The body of the motor (10) is provided with a plurality of support rods (40), the circular tracks where the plurality of support rods (40) are located are coaxial with the impeller (20), the panel portion (2) is provided with mounting holes (21) corresponding one-to-one to the support rods (40), and the circular tracks where all the mounting holes (21) are located are coaxial with the air guide portion (1).

2. The air guide panel for a centrifugal fan according to claim 1, characterized in that: The inner diameter of at least a portion of the wind collecting portion (30) decreases along the wind outlet direction, and the inner diameter of at least a portion of the wind guiding portion (1) increases along the wind outlet direction.

3. The air guide panel for a centrifugal fan according to claim 2, characterized in that: The reduction speed of the portion of the wind collecting portion (30) where the inner diameter is reduced along the wind outlet direction is gradually reduced; The increasing speed of the inner diameter increasing portion of the air guiding portion (1) along the air outlet direction gradually increases.

4. The air guide panel for a centrifugal fan according to claim 2, characterized in that: The parts of the air guiding portion (1) and the air collecting portion (30) that overlap in the axial direction are parallel to each other.

5. The air guide panel for a centrifugal fan according to claim 4, characterized in that: The width W of the gap (3) is 3 to 4 mm.

6. The air guide panel for a centrifugal fan according to claim 1, characterized in that: A bending portion (22) extending in the circumferential direction is provided in the middle of the panel portion (2), and the circular trajectory where all the mounting holes (21) are located is closer to the outer edge of the panel portion (2) than the bending portion (22).

7. The air guide panel for a centrifugal fan according to claim 6, characterized in that: The bent portion (22) is inclined from the inside to the outside toward the motor (10) in the radial direction of the air guide portion (1).

8. The air guide panel for a centrifugal fan according to claim 5, characterized in that: The area where each mounting hole (21) is located is recorded as a mounting area (23), and each mounting area (23) is bent and protrudes in a direction away from the air guide portion (1); wherein, The support rod (40) passes through the mounting hole (21) and is threadedly connected to the nut (50), and the mounting area (23) completely covers the bottom surface of the nut (50).

9. The air guide panel for a centrifugal fan according to claim 8, characterized in that: Each installation area (23) forms an integral plane with a reinforcement portion (24) that is bent and protrudes in a direction away from the air guide portion (1) and a portion of the panel portion (2) located inside the bent portion (22).

10. A centrifugal fan, characterized in that: The invention comprises an air guide panel for a centrifugal fan as described in any one of claims 1 to 9.

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