CN118202157A - Noise reduction type impeller - Google Patents
Noise reduction type impeller Download PDFInfo
- Publication number
- CN118202157A CN118202157A CN202280073660.5A CN202280073660A CN118202157A CN 118202157 A CN118202157 A CN 118202157A CN 202280073660 A CN202280073660 A CN 202280073660A CN 118202157 A CN118202157 A CN 118202157A
- Authority
- CN
- China
- Prior art keywords
- region
- blade
- surface portion
- noise reduction
- blades
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000007664 blowing Methods 0.000 description 7
- 238000009499 grossing Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/38—Blades
- F04D29/384—Blades characterised by form
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/325—Rotors specially for elastic fluids for axial flow pumps for axial flow fans
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/38—Blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The present invention relates to an impeller which is disposed in a duct portion of a fan housing and through which air flows, and which includes: a hub; and a plurality of blades radially formed on an outer surface of the hub, the blades including: the hub connecting part is connected with the hub; a first side surface part and a second side surface part formed on two side surfaces of the hub connecting part; and an outer surface portion connected to the distal end portions of the first and second side portions, the outer surface portion being configured to include a gap portion as a gap between the outer surface portion and an inner surface of the passage portion of the fan cover, at least one of the outer surface portions of the plurality of blades including: a first region portion in which the area of the gap portion is relatively small; and a second region part, the area of the gap part is relatively larger than that of the first region part, thereby reducing noise under the specific frequency band condition and reducing noise under the high power condition.
Description
Technical Field
The present invention relates to a noise reduction impeller for reducing noise generated by air flow resistance under a specific frequency band condition or when the air supply amount is increased.
Background
In general, an axial flow fan causes air to flow in and exhaust air in an axial direction, and rotates at a high speed in order to increase the amount of air supply, and thus has a problem that flow resistance increases and noise increases in a specific frequency band.
The noise source of the axial flow fan is Separation (Separation) or Vortex (Vortex), or in the case of increasing the air supply amount, flow resistance, which makes air flow through smoothly, will be generated between the fan housing and the axial flow fan, which will increase noise.
In particular, in the case of a specific frequency band or an increased air supply amount, the axial flow increases, and thus the gas collides with the blade and generates flow resistance, so that there is a problem in that noise increases.
Disclosure of Invention
Technical problem
An object of the present invention is to provide a noise reduction type impeller that reduces noise by smoothing the flow of air under high power or specific frequency band conditions.
It is still another object of the present invention to provide a noise reduction impeller in which a first region portion for generating a blowing force and a second region portion for reducing flow resistance by smoothing an air flow are formed in one blade at the same time, thereby reducing noise while preventing the blowing force from decreasing.
It is still another object of the present invention to provide a noise reduction type impeller that can minimize noise under specific frequency band conditions by forming another blade disposed adjacent to one blade into an uneven shape.
Technical proposal
In order to solve the above-described problems, the present invention provides a noise reduction impeller which is disposed in a duct portion of a fan housing through which air flows, and includes: a hub; and a plurality of blades radially formed on an outer surface of the hub, the blades including: the hub connecting part is connected with the hub; a first side surface part and a second side surface part formed on two side surfaces of the hub connecting part; and an outer surface portion connected to the distal end portions of the first and second side portions, the outer surface portion being configured to include a gap portion as a gap between the outer surface portion and an inner surface of the passage portion of the fan cover, at least one of the outer surface portions of the plurality of blades including: a first region portion in which the area of the gap portion is relatively small; and a second area portion, the area of the gap portion is relatively larger than that of the first area portion, the first area portion can play a role of generating air supply, and the second area portion can play a role of reducing noise by reducing flow resistance.
The first region portion of the outer surface portion of the vane may be connected to the distal end portion of the first side surface portion, and the second outer surface portion may be connected to the distal end portion of the second side surface portion, so that the first region portion and the second region portion may be formed at the outer surface portion of one vane.
The radius of curvature of the first region portion and the second region portion may be the same and may be formed at different heights, so that the first region portion and the second region portion may be formed at the outer surface portion of one blade.
The first region may be connected to the first side surface portion and the second side surface portion to be located at both side edges of the outer surface portion, and the second region may be located at a center of the outer surface portion, which is a position between the first region, so that the first region and the second region may be formed at the outer surface portion of one blade.
The plurality of blades may include a second blade disposed adjacent to the first blade, and an outer surface portion of the first blade and an outer surface portion of the second blade may be formed in different shapes to reduce noise under a specific frequency band condition.
The first region part of the first blade may be connected to the distal end portion of the first side portion, the second region part may be connected to the second side portion, the first region part of the second blade may be connected to the second side portion, and the second region part may be connected to the first side portion, thereby reducing noise under a specific frequency band condition and reducing noise under a high power condition.
The blade may include: a plurality of first blades; and a second blade disposed between the first blades, wherein the second blade may have a length smaller than that of the first blade, a first region may be formed on an outer surface portion of the first blade, and a second region may be formed on the second blade.
ADVANTAGEOUS EFFECTS OF INVENTION
As described above, the impeller of the present invention forms the first and second area portions having the different areas of the gap portion by the different heights on the outer surface portion of the blade, so as to minimize the flow resistance of the fluid while maintaining the air blowing performance, thereby reducing noise.
Also, noise under a specific frequency band condition can be reduced by forming the outer surface portion of one blade to be different from the outer surface portion of the other blade disposed adjacent to the outer surface portion of the one blade.
Drawings
Fig. 1 is a top view of a fan housing and impeller according to a first embodiment of the present invention.
Fig. 2 is a top view of an impeller according to a first embodiment of the present invention.
Fig. 3 is a top view of an impeller according to a second embodiment of the present invention.
Fig. 4 is a top view of an impeller according to a third embodiment of the present invention.
Fig. 5 is a top view of an impeller according to a fourth embodiment of the present invention.
Fig. 6 is a top view of an impeller according to a fifth embodiment of the present invention.
Fig. 7 is a top view of an impeller according to a sixth embodiment of the present invention.
Fig. 8 is a graph of band-based noise for an impeller of the present invention.
Detailed Description
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this process, the sizes, shapes, and the like of the constituent elements shown in the drawings may be exaggerated in order to ensure clarity and convenience of description. Also, a plurality of terms specifically defined in consideration of the structure and function of the present invention may be different according to intention or convention of a user, an application person. Such terms should be defined based on the entire contents of the present specification.
Referring to fig. 1, the present invention may include: a fan cover 10 that forms a duct 12 so that air flows in the axial direction; and an impeller 20 disposed in the duct portion 12 of the fan housing 10 to flow the gas in the axial direction.
The impeller 20 may include: a hub 22 connected to the motor; and a plurality of blades 24 radially spaced at predetermined intervals along the circumferential direction of the hub 22.
As shown in fig. 2, blade 24 may include: a hub connection portion 32 connected to the hub 22; the first side surface 34 and the second side surface 36 are separated from the adjacent blades by a predetermined interval; and an outer surface portion 40 configured to have a gap portion 14 as a space from an inner surface of the passage portion 12 of the fan cover 10.
If the air flow rate is increased under the specific frequency band condition, the impeller 20 as described above increases the amount of air flowing through the impeller 20, and thus there is a problem in that noise is generated due to the flow resistance of the air. The flow resistance will occur due to collision of air flowing through the blades in front of the blades 24, which is not smooth, with the blades in case of an increased air volume or under a specific frequency band, and vortex flow of air flowing through the blades in rear of the blades, which may collide with each other to generate noise.
Accordingly, in the present embodiment, the present invention provides an impeller that can minimize flow resistance and reduce noise and minimize degradation of air supply performance by changing the shape of the outer surface portion 40 of the blade 24.
As shown in fig. 2, in the outer surface portion of the blade 20 of the first embodiment, the first region portion 42 where the area of the gap portion 14 is small and the second region portion 44 where the area of the gap portion 14 is relatively larger than that of the first region portion 42 are formed in one blade 24 by forming a small space with the inner surface of the fan housing 10, so that air having flow resistance generated by the second region portion 44 smoothly flows and the first region portion 42 performs the function of the blade itself generating the blowing force, whereby it is possible to minimize noise generated due to the flow resistance while minimizing the drop of the blowing force.
The first region 42 is connected to the distal end portion of the first side surface portion 34, and the second region 44 is connected to the distal end portion of the second side surface portion 36 of the blade, so that the first region 42 and the second region form a stepped shape having different heights, and the outer surface portion 40 of one blade can be divided into the first region 42 and the second region 44.
The first region 42 and the second region 44 have the same radius of curvature and different heights, so that the areas of the gap portions 14 are different from each other.
In this case, it is preferable that the length of the first region part 42 is smaller than the length of the second outer surface part 44. That is, if the length L1 of the first outer surface portion 42 is equal to or greater than the set value, the air blowing performance is not greatly affected, but the larger the length L2 of the second outer surface portion 44 is, the larger the area of the gap portion 14 becomes, so that the air smoothly flows, and the noise reduction performance can be improved.
Of course, the length of the first region 42 may be greater than the second region 44, or the length of the first region 42 and the length of the second region 44 may be the same.
As described above, the first and second area portions 42 and 44 are integrally formed on the outer surface portion 40 of one blade 24, and the flow resistance is minimized by the second area portion 44 while maintaining the air blowing performance by the first area portion 42, thereby minimizing the generation of noise.
As shown in fig. 3, in the outer surface portion 50 of the blade of the second embodiment, the first region portions 52, 54 are formed at both side edges of the outer surface portion 50 of the blade, and the second region portion 56 is formed at the center of the outer surface portion 50 of the blade. The first outer surface portions 52, 54 are located at both side portions of the outer surface portion 50 connected to the first side surface portion 34 and the second side surface portion 36 of the blade 24, and the second region portion 56 may be formed between the first region portions 52, 54.
The impeller of this second embodiment may also be such that the sum of the lengths of the first region portions 52, 54 formed on both sides of the outer surface portion of the blade is smaller than the length of the second region portion 56 formed at the center of the outer surface portion 50 of the blade.
The impeller of the second embodiment described above minimizes the flow resistance of air through the first region portions 52, 54 located on both sides of the outer surface portion of the blade, and the air-sending force will be generated through the second region portion 56 located at the center of the outer surface portion 50 of the blade.
As shown in fig. 4, in the outer surface portion 60 of the outer surface portion 24 of the blade of the third embodiment, the first area portion 62 is formed in the center of the outer surface portion 60 of the blade, and the second outer surface portions 64, 66 are formed on both side edges of the outer surface portion 60 of the blade. The second outer surface portions 64, 66 of the third embodiment are located at both side portions of the outer surface portion 60 connected to the first and second side surface portions 34, 36 of the vane, and the first outer surface portion 62 may be formed between the second outer surface portions 64, 66.
As shown in fig. 5, the plurality of blades of the fourth embodiment include the second blade 72 disposed adjacent to the first blade 70, and the outer surface portion 80 of the first blade 70 and the outer surface portion 90 of the second blade 72 may be different from each other in shape. That is, the outer surface portion 80 of the first vane 70 and the outer surface portion 90 of the second vane 72 may form an uneven shape.
Noise can be minimized at the same time under high power and specific frequency band conditions by making the shapes of the outer surface portion 80 of the first blade 70 and the outer surface portion 90 of the second blade 72 different from each other. That is, the air flow at a specific frequency band can be made smooth by forming the outer surface portion 80 of the first blade 70 and the outer surface portion 90 of the second blade 72 in different shapes, so that noise generated at a high power condition can be minimized while noise generated at a specific frequency band condition is minimized.
The outer surface portion 80 of the first vane 70 may include: a first region 84 connected to the second side surface 36; and a second region 82 connected to the first side 34, and an outer surface 90 of the second vane 72 may include: a first region 94 connected to the first side 34; and a second region 92 connected to the second side surface 36. That is, the first and second region portions 84 and 82 of the first blade 70 and the first and second region portions 94 and 92 of the second blade 72 may be formed in mutually opposite shapes, and thus may be formed in a non-uniform shape.
For example, if the number of blades is 6, 3 blades may form the outer surface portion 80 of the first blade 70, and the remaining 3 blades may form the outer surface portion 90 of the second blade 72 to be disposed between the first blades 70.
As shown in fig. 6, the blade of the fifth embodiment includes a first blade 110 and a second blade 120 disposed adjacently, and an outer surface portion 130 of the first blade 110 includes: the first region 134, 136 is connected to the first side surface 34 and the second side surface 36 of the first blade 110; and a second outer surface portion 132 located at the center of the outer surface portion 130 of the blade, the outer surface portion 140 of the second blade 120 including: the second area portions 142, 144 connected to the first side surface portion 34 and the second side surface portion 36 of the second blade 120; and a first region 146 located at the center of the outer surface 140.
The plurality of blades of the fifth embodiment as described above makes the number of the first blades and the second blades the same, and the second blades may be arranged between the first blades.
As shown in fig. 7, the blade of the sixth embodiment includes a plurality of second blades 210 arranged between a plurality of first blades 200, the length H1 of the first blades 200 is formed to be maximally long, the length H2 of the second blades 210 is shorter than the length H1 of the first blades 200, and the outer surface portions of the first blades 200 and the outer surface portions of the second blades 210 are formed in uneven shapes.
That is, the first area portion is formed on the outer surface portion of the first blade 200, and the second area portion is formed on the outer surface portion of the second blade 210, so that the air having the flow resistance smoothly flows through the second area portion formed between the outer surface portion of the second blade 210 and the fan housing and functions as the blade itself, and the noise due to the flow resistance can be minimized while minimizing the drop of the air supply force.
Fig. 8 is a graph showing the band-based noise of the impellers of the first to sixth embodiments of the present invention, and it can be confirmed that the noise is reduced under a specific (700 Hz) band H condition.
While the present invention has been shown and described with reference to certain preferred embodiments, the present invention is not limited to the above embodiments, and various changes and modifications may be made by one of ordinary skill in the art without departing from the spirit of the present invention.
Industrial applicability
The present invention relates to an axial flow fan for sucking and exhausting air in an axial direction, which can smooth the flow of air by forming the outer surface of the blade into an uneven shape, thereby reducing noise.
Claims (10)
1. A noise-reducing impeller is characterized in that,
A duct portion arranged in the fan housing and through which air flows, the duct portion including:
A hub; and
A plurality of blades radially formed on the outer surface of the hub,
The blade includes:
the hub connecting part is connected with the hub;
a first side surface part and a second side surface part formed on two side surfaces of the hub connecting part; and
An outer surface portion connected to the distal end portions of the first and second side portions and configured to have a gap portion as a gap between the outer surface portion and the inner surface of the passage portion of the fan housing,
At least one of the outer surface portions of the plurality of blades includes:
a first region portion in which the area of the gap portion is relatively small; and
And a second region portion, wherein the area of the gap portion is relatively larger than that of the first region portion.
2. The noise reduction impeller of claim 1, wherein,
The first area portion is connected to a distal end portion of the first side portion,
The second outer surface portion is connected to the end portion of the second side surface portion,
A first area portion and a second area portion are formed on an outer surface portion of one blade.
3. The noise reduction impeller according to claim 1, wherein the first and second region portions have the same radius of curvature.
4. The noise reduction impeller of claim 1, wherein the length of the second region is greater than the length of the first region.
5. The noise reduction impeller of claim 1, wherein,
The first area part is connected with the first side surface part and the second side surface part and is positioned at the two side edges of the outer surface part,
The second region is located at the center of the outer surface portion which is a position between the first region.
6. The noise reduction impeller of claim 5, wherein,
The first region is located at the center of the outer surface portion,
The second area part is connected with the first side surface part and the second side surface part and is positioned at the two side edges of the outer surface part.
7. The noise reduction impeller of claim 1, wherein,
The plurality of vanes includes a second vane disposed adjacent to the first vane,
The outer surface portion of the first blade and the outer surface portion of the second blade form different shapes.
8. The noise reduction impeller of claim 7, wherein,
The first region of the first blade is connected to the end of the first side, the second region is connected to the second side,
The first region of the second blade is connected to the second side surface, and the second region is connected to the first side surface.
9. The noise reduction impeller of claim 7, wherein,
The first blade has a first region formed at both side edges of the outer surface portion, a second region formed at the center of the outer surface portion,
The first region part of the second blade is formed at the center of the outer surface part, and the second region part is formed at both side edges of the outer surface part.
10. The noise reduction impeller of claim 1, wherein,
The blade includes:
A plurality of first blades; and
A second blade disposed between the first blades,
The length (H2) of the second blade is smaller than the length (H1) of the first blade,
A first region is formed on the outer surface of the first blade, and a second region is formed on the second blade.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2021-0152501 | 2021-11-08 | ||
| KR20210152501 | 2021-11-08 | ||
| PCT/KR2022/017328 WO2023080739A1 (en) | 2021-11-08 | 2022-11-07 | Noise reduction-type impeller |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118202157A true CN118202157A (en) | 2024-06-14 |
Family
ID=86241936
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202280073660.5A Pending CN118202157A (en) | 2021-11-08 | 2022-11-07 | Noise reduction type impeller |
Country Status (3)
| Country | Link |
|---|---|
| KR (1) | KR102703624B1 (en) |
| CN (1) | CN118202157A (en) |
| WO (1) | WO2023080739A1 (en) |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3577739B2 (en) * | 1994-06-15 | 2004-10-13 | 松下電工株式会社 | Axial fan |
| JP4492060B2 (en) * | 2003-08-06 | 2010-06-30 | パナソニック株式会社 | Blower impeller |
| KR100753025B1 (en) | 2005-09-02 | 2007-08-30 | 주식회사 오팬 | Low noise cooling fan equipped with flow guide part on lower surface and tip |
| JP5434235B2 (en) * | 2009-04-27 | 2014-03-05 | 三洋電機株式会社 | Outdoor unit |
| JP6154990B2 (en) * | 2012-04-10 | 2017-06-28 | シャープ株式会社 | Propeller fan for electric fan, electric fan equipped with the same, and mold for molding propeller fan for electric fan |
| US20190309759A1 (en) | 2016-11-18 | 2019-10-10 | Mitsubishi Heavy Industries, Ltd. | Compressor, and method for producing blade thereof |
| US10808726B2 (en) * | 2017-04-24 | 2020-10-20 | Asia Vital Components Co., Ltd. | Fan structure |
| KR102263993B1 (en) | 2018-10-10 | 2021-06-11 | 오텍캐리어 주식회사 | Fan for Noise and Vibration Reduction and Air Conditioner with the Same |
| CN110145492A (en) * | 2019-07-06 | 2019-08-20 | 代元军 | A kind of mining partial axial ventilator of the V-shaped structure of blade tip |
-
2022
- 2022-11-07 CN CN202280073660.5A patent/CN118202157A/en active Pending
- 2022-11-07 WO PCT/KR2022/017328 patent/WO2023080739A1/en active Application Filing
- 2022-11-08 KR KR1020220148000A patent/KR102703624B1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| WO2023080739A1 (en) | 2023-05-11 |
| KR102703624B1 (en) | 2024-09-05 |
| KR20230067559A (en) | 2023-05-16 |
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