An impeller for a cross-flow fan and the cross-flow fan itself.

Abstract

This invention provides an impeller for a cross-flow fan and a cross-flow fan itself. The impeller includes multiple blades and a disc for fixing the blades. The impeller has a longitudinal axis, and the multiple blades are arranged along the length of the impeller and spaced apart around the longitudinal axis. The impeller also includes an elastic ring. The inner circumference of the elastic ring in its natural state is A, and the outer circumference of the circumscribed circle formed by the multiple blades is B, where A < B. The elastic ring is fitted onto the outer circumference of the blades by elastic deformation. This reduces vibration and thus lowers the noise generated by the cross-flow fan.

Description

Technical Field

[0001] This utility model relates to the field of fans, and in particular to an impeller for a cross-flow fan and a cross-flow fan. Background Technology

[0002] Cross-flow fans are widely used in industrial and manufacturing fields, and their basic components are as follows: Figure 1 As shown, it consists of a motor that provides power, a volute that restricts airflow, and an impeller that drives the airflow. When the cross-flow fan is working, the impeller rotates at high speed around the shaft.

[0003] To improve operational stability and achieve better impeller dynamic balance, and to reduce impeller wind resistance and thus lower load power, impeller blades are often designed with a thin-plate structure. When a cross-flow fan is working, the impeller pushes the airflow, and the airflow also generates a reaction force on the impeller, causing its blades to vibrate. The impeller disc, which is meant to fix the fan, cannot effectively eliminate the vibration, thus generating noise. Utility Model Content

[0004] To address the problems in the prior art, this utility model provides an impeller for a cross-flow fan and a cross-flow fan, which reduces vibration and thus lowers the noise generated by the cross-flow fan.

[0005] An impeller for a cross-flow fan includes multiple blades and a disc for fixing the blades. The impeller has a longitudinal axis, and the multiple blades are arranged along the length of the impeller and spaced apart around the longitudinal axis. The impeller also includes an elastic ring. The inner circumference of the elastic ring in its natural state is A, and the outer circumference of the circumscribed circle formed by the multiple blades is B, where A < B. The elastic ring is fitted onto the outer circumference of the blades by elastic deformation.

[0006] The advantage is that when the elastic ring is fitted around the outer periphery of the blade, the contraction force of the elastic ring is applied to the blade. The contraction force of the elastic ring counteracts the force that causes the blade to vibrate, thereby reducing vibration and noise.

[0007] Preferably, the wheel has multiple discs, and the elastic ring is provided between adjacent discs.

[0008] The advantage is that by setting up multiple discs, the blades can be reliably fixed, preventing blade deformation and providing a certain degree of noise reduction; by setting elastic rings between adjacent discs, the noise reduction effect is further optimized.

[0009] Preferably, the width of the elastic ring is C, and the distance between adjacent discs is D, where 0.02D≤C≤0.25D.

[0010] The advantage is that the contraction force of the elastic ring can counteract the force that causes the blades to vibrate, effectively reducing noise, without significantly reducing the air volume of the fan. When C < 0.02D, the contraction force generated by the elastomer is too small to effectively counteract the force that causes the blades to vibrate, and the vibration cannot be eliminated. When C > 0.25D, its coverage area is too large, which will significantly reduce the air volume of the fan and affect the performance of the fan.

[0011] Preferably, the distance D between adjacent discs is no greater than 300mm.

[0012] The advantage is that it effectively reduces vibration in the middle of the fan blades, thereby reducing noise; if D is too large, it cannot effectively eliminate vibration in the middle of the fan blades, resulting in relatively high noise.

[0013] Preferably, the wheel is made of an elastic material with a Shore A hardness between 30 and 90 degrees; and / or the surface of the blade has an elastic coating.

[0014] The advantage is that the wheel is made of a specific elastic material, which can not only fix the fan blades but also absorb the vibration of the fan blades, thereby reducing noise; the elastic coating generates elastic tension when the blades vibrate and deform, which counteracts the force of vibration, thereby reducing vibration and noise.

[0015] Preferably, 0.25B≤A≤0.95B.

[0016] The advantage is that the contraction force of the elastic ring counteracts the force that causes the blade to vibrate, thereby reducing vibration and noise. When A < 0.25B, the contraction force applied to the blade by the elastic body is too large, causing blade deformation and affecting the smoothness of impeller operation; when A > 0.95B, the contraction force applied to the blade is too small to effectively counteract the force that causes the blade to vibrate, thus failing to effectively eliminate vibration and achieving the expected noise reduction effect.

[0017] Preferably, the inner wall of the elastic ring is provided with ribs, and the impeller is provided with notches that cooperate with the ribs.

[0018] The advantage is that it ensures the position of the elastic ring is fixed and will not be displaced due to the movement of the impeller, thus further improving the reliability of noise reduction.

[0019] Preferably, the impeller includes a first side away from the longitudinal axis and a second side opposite to the first side; The first side is provided with a serrated structure for diverting airflow, the serrated structure being formed by the end face of the first side being recessed towards the second side; and / or the second side is provided with a guide tooth for guiding airflow, the guide tooth comprising a plurality of teeth and spaced apart along the length direction of the blade, the guide tooth being located on the side surface of the blade.

[0020] The advantage is that the serrated structure cuts through the airflow, reducing air resistance on the blades, decreasing the force on the blades, reducing vibration, and thus reducing noise. The serrated structure disrupts the airflow, preventing the blade vibrations from resonating and amplifying their amplitude, thereby achieving noise reduction.

[0021] By guiding the airflow through the guide teeth, when the impeller is installed inside the volute of the cross-flow fan, the airflow enters the volute smoothly and steadily. During the operation of the fan, the airflow is stable and there is no turbulent airflow, which reduces the vibration of the blades and thus reduces the operating noise.

[0022] Preferably, the blade includes at least a first section close to the longitudinal axis and a second section away from the longitudinal axis. Both the first and second sections are arc-shaped and smoothly connected, with the curvature of the first section being greater than that of the second section. The advantage is that the first section, using a larger radius of curvature, acts as a buffer section to pre-rectify and decelerate the airflow, reducing inlet impact losses. The second section, using a smaller radius of curvature, acts as a power section, increasing static pressure and kinetic energy through stronger curvature, thus accelerating the airflow in. This division of labor allows the airflow to better conform to the blade profile when passing through it, reducing separation and eddies, thereby reducing airflow noise and ultimately lowering overall noise levels.

[0023] Alternatively, the blade includes a second side close to the longitudinal axis and a first side away from the longitudinal axis. The blade is arc-shaped, and the angle formed by the tangents of the second sides of adjacent blades on the impeller cross-section is α. The angles of α formed by multiple adjacent blades are different. The angle of attack of the blade on the first side is β. The angles of attack β of multiple blades are different. The advantage is that this arrangement makes the effect of each blade on the airflow different when the impeller is running, so that resonance will not be formed, thereby reducing noise.

[0024] Alternatively, the blade includes a second side close to the longitudinal axis and a first side away from the longitudinal axis. On the cross-section of the impeller, the line connecting the second side and the first side is inclined relative to the direction perpendicular to the axis of the impeller. The second side is rolled up in the same direction as the blade's inclination direction. The advantage is that the rolled up design improves the blade's own stiffness, making it less prone to vibration during operation, thereby further reducing noise.

[0025] A cross-flow fan includes an impeller as described above. The cross-flow fan also includes a body, a motor for driving the impeller to rotate, and a rotating shaft connected to the motor. The rotating shaft is connected to the impeller. The body has a mounting cavity, and the impeller is mounted in the mounting cavity of the body. The motor is located on one side of the body.

[0026] The advantage is that cross-flow fans using this impeller operate with less noise than existing technologies. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a cross-flow fan in the existing technology; Figure 2 This is a schematic diagram of the impeller structure of a cross-flow fan according to the present invention; Figure 3 This is a cross-sectional view of an impeller structure according to Embodiment 1 of this utility model; Figure 4 This is a schematic diagram of the elastic ring belt in Embodiment 1 of this utility model; Figure 5 This is a cross-sectional view of an impeller structure according to Embodiment 2 of this utility model; Figure 6 This is a schematic diagram of the elastic ring belt in Embodiment 2 of this utility model; Figure 7 This is a schematic diagram of the blade notch structure in Embodiment 2 of this utility model; Figure 8 This is a schematic diagram of the structure of an impeller according to Embodiment 3 of this utility model; Figure 9 yes Figure 8 An enlarged view of the location indicated by A in the middle; Figure 10 This is a schematic diagram of the structure of an impeller according to Embodiment 4 of this utility model; Figure 11 yes Figure 10 A magnified view of the location indicated by B in the middle; Figure 12 This is a cross-sectional view of an impeller structure according to Embodiment 5 of this utility model; Figure 13 This is a cross-sectional view of an impeller structure according to Embodiment 6 of this utility model; Figure 14 This is a cross-sectional view of an impeller structure according to Embodiment 7 of this utility model; Figure 15 This is a schematic diagram of the structure of a cross-flow fan described in this utility model.

[0028] The names of the components shown in the diagram are as follows: 1. Impeller; 101. Blade; 1011. First side; 1012. Second side; 1013. First section; 1014. Second section; 102. Disc; 103. Shaft; 104. Notch; 105. Serrated structure; 106. Drainage tooth; 2. Elastic ring; 201. Rib; 3. Body; 301. Mounting cavity; 4. Motor. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings. Example

[0030] like Figures 2 to 4 As shown, an impeller 1 of a cross-flow fan includes multiple blades 101 and a disc 102 for fixing the blades 101. The impeller 1 has a longitudinal axis (L-L'). The multiple blades 101 are arranged along the length of the impeller 1 and spaced apart around the longitudinal axis of the impeller 1. The impeller 1 also includes an elastic ring 2. The inner circumference of the elastic ring 2 in its natural state is A, and the outer circumference of the circumscribed circle formed by the multiple blades 101 is B, where A < B. The elastic ring 2 is fitted onto the outer circumference of the blades 101 by elastic deformation. The advantage is that when the elastic ring 2 is fitted onto the outer circumference of the blades 101, the contractile force of the elastic ring 2 is applied to the blades 101. The contractile force of the elastic ring 2 counteracts the force that causes the blades 101 to vibrate, thereby reducing vibration and noise.

[0031] In this invention, the natural state of the elastic ring 2 refers to the state of the elastic ring 2 when it is not subjected to external force.

[0032] The disks 102 are multiple, and the elastic rings 2 are provided between adjacent disks 102. The advantage is that the multiple disks 102 reliably fix the blades 101, preventing deformation and providing a certain degree of noise reduction; the elastic rings 2 between adjacent disks 102 further optimize the noise reduction effect. More specifically, the multiple disks 102 include at least a first disk 102 and a second disk 102 located at both ends of the blades 101; further, the multiple disks 102 may also include at least one middle disk 102 located between the first and second disks 102. Further, the distance D between adjacent disks 102 is no greater than 300mm; if D is too large, it cannot effectively eliminate vibration in the middle of the blades, preferably D = 100mm.

[0033] The width of the elastic ring 2 is C, and the distance between adjacent impellers 102 is D, where 0.02D ≤ C ≤ 0.25D. The advantage is that the contraction force of the elastic ring can counteract the force causing vibration of the blades 101, effectively reducing noise, without significantly reducing the fan's airflow. When C < 0.02D, the contraction force generated by the elastic body is too small to effectively counteract the force causing vibration of the blades 101, and vibration cannot be eliminated. When C > 0.25D, its coverage area is too large, significantly reducing the fan's airflow and affecting its performance. The width of the elastic ring 2 is the distance extending along the length of the impeller 1. Preferably, C = 0.1D.

[0034] Furthermore, 0.25B ≤ A ≤ 0.95B. The advantage is that the contractile force of the elastic ring 2 counteracts the force causing vibration in the blade 101, thereby reducing vibration and noise. When A < 0.25B, the elastic body, wrapped around the outer circumference of the blade 101, applies too much contractile force, causing deformation of the blade 101 and affecting the smoothness of impeller 1's operation. When A > 0.95B, the contractile force applied to the blade 101 is too small to effectively counteract the force causing vibration, thus failing to effectively eliminate vibration and achieving the desired noise reduction effect. Preferably, A = 0.8B.

[0035] Furthermore, to further reduce noise, the wheel 102 is made of an elastic material with a Shore A hardness between 30 and 90 degrees. The advantage is that by using a specific elastic material, the wheel 102 can both fix the fan blades and absorb their vibrations, thus reducing noise; preferably, the elastic material has a Shore A hardness of 60 degrees. When there are multiple wheel 102s, all wheel 102s can be made of elastic material; alternatively, one or more of them can be made of elastic material.

[0036] Furthermore, the surface of the blade 101 has an elastic coating. The advantage is that the elastic coating generates elastic tension when the blade 101 vibrates and deforms, counteracting the vibration force, thereby reducing vibration and noise.

[0037] In this embodiment, the inner surface of the elastic ring is smooth.

[0038] Understandably, in this embodiment, in order to obtain a better noise reduction effect, the blade 101 surface is coated with an elastic coating and the wheel 101 is made of an elastic material, which can be combined at the same time. Example

[0039] The difference between this embodiment and Embodiment 1 lies in the different mating structures between the elastic ring 2 and the blade 101. For example... Figure 1 , Figures 5 to 7 As shown, the inner wall of the elastic ring 2 is provided with a rib 201, and the blade 101 is provided with a notch 104 that mates with the rib 201. The advantage is that it ensures the position of the elastic ring 2 is fixed and will not shift due to the movement of the impeller 1, further improving noise reduction reliability. The rib 201 can be annular or multiple protrusions spaced apart on the inner wall surface of the elastic ring 2; all blades 101 of the impeller 1 are provided with notches 104, or only some blades may have notches 104. Example

[0040] The difference between this embodiment and Embodiments 1 or 2 lies in the specific structure of the blade 101. For example... Figure 1 , Figure 8 , 9As shown, the impeller 1 includes a first side 1011 away from the longitudinal axis (L-L') of the impeller 1 and a second side 1012 opposite to the first side 1011. The first side 1011 is provided with a serrated structure 105 for diverting airflow, and this serrated structure 105 is formed by a concave shape between the end face of the first side 1011 and the second side 1012. The advantage is that the serrated structure 105 cuts the airflow, reducing air resistance to the blades 101, reducing the force on the blades 101, reducing vibration, and thus reducing noise. The serrated structure 105 disrupts the airflow, preventing the vibration of the blades 101 from resonating and amplifying its amplitude, thereby achieving noise reduction. More specifically, in this example, the serrated structure 105 consists of multiple sharp teeth evenly and spaced along the length of the blades 101, with a spacing E between adjacent sharp teeth not exceeding 5 mm. If the distance is too large, its proportion is too small, and it cannot effectively cut the airflow. Preferably, the spacing between adjacent sharp teeth is 1.5 mm. Example

[0041] The difference between this embodiment and the previous embodiment lies in the specific structure of the blade 101. For example... Figure 1 , Figure 10 , 11 As shown, the impeller 1 includes a second side 1012 near its longitudinal axis (L-L'). The second side 1012 is provided with guide teeth 106 for guiding airflow. Multiple guide teeth 106 are spaced apart along the length of the blade 101 and are located on the side of the blade 101. The advantage is that by guiding / directing the airflow through the guide teeth 106, when the impeller 1 is assembled inside the volute of the cross-flow fan, the airflow smoothly and steadily enters the volute. During fan operation, the airflow is stable and free of turbulent airflow, resulting in less vibration of the blade 101 and thus lower operating noise. More specifically, the multiple guide teeth 106 are evenly spaced along the length of the blade 101, and the distance F between adjacent guide teeth 106 is no greater than 5mm. If the distance is too large, the airflow cannot be effectively stabilized. Preferably, the distance between adjacent guide teeth 106 is 1.5mm.

[0042] Understandably, the first and second ends of the blade 101 may simultaneously have the serrated structure 105 and the drainage tooth 106 as in Embodiments 3 and 4. Example

[0043] The difference between this embodiment and the previous embodiment lies in the specific structure of the blade 101. For example... Figure 1 , Figure 12As shown, the blade 101 includes a second side 1012 close to the longitudinal axis (L-L') of the impeller 1 and a first side 1011 away from the longitudinal axis (L-L') of the impeller 1. On the cross-section of the impeller 1, the line connecting the second side 1012 and the first side 1011 is inclined relative to the direction perpendicular to the axis of the impeller 1. The second side 1012 is designed to be rolled up in the same direction as the inclination direction of the blade 101. The advantage is that the rolled up design improves the stiffness of the blade 101 itself, making it less prone to vibration during operation, thereby further reducing noise. Example

[0044] The difference between this embodiment and the previous embodiment lies in the specific structure of the blade 101. For example... Figure 1 , Figure 13 As shown, the blade 101 includes a second side 1012 close to the longitudinal axis (L-L') of the impeller 1 and a first side 1011 away from the longitudinal axis (L-L') of the impeller 1. The blade 101 is arc-shaped. On the cross-section of the impeller 1, the included angle formed by the tangents of the second sides 1012 of adjacent blades 101 is α. The angle α formed by multiple adjacent blades 101 is different. The windward angle β of the blade 101 on the first side 1011 is β. The windward angle β of multiple blades 101 is different. The advantage is that this arrangement makes the effect of each blade 101 on the airflow different when the impeller 1 is running, thus preventing resonance and reducing noise. Furthermore, the number of blades 101 is a prime number. When the impeller 1 runs at different speeds, the probability that the vibration frequencies of each blade 101 are the same is greatly reduced, thereby reducing the possibility of resonance.

[0045] In this example, the angle of attack β is as follows: Figure 13 As shown, more specifically, the angle of attack refers to the angle formed by the external tangent line at the intersection of the external tangent circle of multiple blades and the external tangent line of the first side of the blade, and the external tangent line of the first side of the curved blade.

[0046] Furthermore, such as Figure 13 As shown, γ = 90 degrees. Example

[0047] The difference between this embodiment and the previous embodiment lies in the specific structure of the blade 101. For example... Figure 1 , Figure 14As shown, the blade 101 includes at least a first section 1013 near the longitudinal axis (L-L') of the impeller 1 and a second section 1014 away from the longitudinal axis (L-L') of the impeller 1. Both the first section 1013 and the second section 1014 are arc-shaped and smoothly connected. The curvature of the first section 1013 is greater than that of the second section 1014. The advantage is that the first section 1013, with its larger radius of curvature, acts as a buffer section to pre-rectify and decelerate the airflow, reducing inlet impact loss. The second section 1014, with its smaller radius of curvature, acts as a power section, increasing static pressure and kinetic energy through stronger curvature, thus accelerating the airflow in. This division of labor allows the airflow to better conform to the blade profile when passing through the blade 101, reducing separation and eddies, thereby reducing airflow noise and ultimately lowering overall noise levels.

[0048] like Figures 1 to 15 As shown, a cross-flow fan includes an impeller 1 as described in any of the above embodiments. The fan also includes a body 3, a motor 4 for driving the impeller 1 to rotate, and a rotating shaft 103 connected to the motor 4. The rotating shaft 103 is connected to the impeller 1. The body 3 has a mounting cavity 301, and the impeller 1 is mounted within the mounting cavity 301. The motor 4 is located on one side of the body 3. The advantage is that the cross-flow fan using this impeller 1 produces less noise during operation than existing technologies.

[0049] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, make equivalent substitutions for some of the technical features, or freely combine multiple embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An impeller of a cross-flow fan comprising a plurality of blades, a disc for fixing the blades, the impeller having a longitudinal axis, a plurality of the blades being arranged in a lengthwise direction of the impeller and a plurality of the blades being disposed at intervals around the longitudinal axis, characterized in that, The impeller also includes an elastic ring, the inner circumference of which is A in its natural state, and the outer circumference of the circumscribed circle formed by the plurality of blades is B, where A < B. The elastic ring is fitted onto the outer circumference of the blades by means of elastic deformation.

2. The impeller of claim 1, wherein The wheel has multiple discs, and the elastic ring is provided between adjacent discs.

3. The impeller of claim 2, wherein The width of the elastic ring is C, and the distance between adjacent discs is D, where 0.02D≤C≤0.25D.

4. The impeller of claim 2, wherein The distance D between adjacent discs is no greater than 300mm.

5. The impeller of claim 1, wherein The wheel is made of an elastic material with a Shore A hardness between 30 and 90 degrees; and / or the surface of the blade has an elastic coating.

6. The impeller of claim 1, wherein 0.25B≤A≤0.95B.

7. The impeller of claim 1, wherein The inner wall of the elastic ring is provided with ribs, and the blade is provided with notches that cooperate with the ribs.

8. The impeller of claim 1, wherein The impeller includes a first side away from the longitudinal axis and a second side opposite to the first side; The first side is provided with a serrated structure for diverting airflow, the serrated structure being formed by the end face of the first side being recessed towards the second side; and / or the second side is provided with a guide tooth for guiding airflow, the guide tooth comprising a plurality of teeth and spaced apart along the length direction of the blade, the guide tooth being located on the side surface of the blade.

9. The impeller of claim 1, wherein The blade includes at least a first segment close to the longitudinal axis and a second segment away from the longitudinal axis. The first segment and the second segment are both arc-shaped and smoothly connected. The curvature of the first segment is greater than that of the second segment. Alternatively, the blade includes a second side close to the longitudinal axis and a first side away from the longitudinal axis. The blade is arc-shaped. On the cross-section of the impeller, the included angle formed by the tangents of the second sides of adjacent blades is α. The included angle α formed by multiple adjacent blades is different. The windward angle β of the blade on the first side is β. The windward angle β of multiple blades is different. Alternatively, the blade includes a second side close to the longitudinal axis and a first side away from the longitudinal axis. In the cross-section of the impeller, the line connecting the second side and the first side is inclined relative to a direction perpendicular to the axis of the impeller, and the second side is designed to be rolled in the same direction as the blade's inclination direction.

10. A cross-flow fan characterized by, The cross-flow fan includes the impeller of any one of claims 1 to 9, and further includes a body, a motor for driving the impeller to rotate, and a rotating shaft connected to the motor. The rotating shaft is connected to the impeller. The body has a mounting cavity, the impeller is mounted in the mounting cavity of the body, and the motor is located on one side of the body.

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