WO2024011964A1 - Silencieux - Google Patents

Silencieux Download PDF

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Publication number
WO2024011964A1
WO2024011964A1 PCT/CN2023/086308 CN2023086308W WO2024011964A1 WO 2024011964 A1 WO2024011964 A1 WO 2024011964A1 CN 2023086308 W CN2023086308 W CN 2023086308W WO 2024011964 A1 WO2024011964 A1 WO 2024011964A1
Authority
WO
WIPO (PCT)
Prior art keywords
tube
sound
reflecting
waveguide
sound absorbing
Prior art date
Application number
PCT/CN2023/086308
Other languages
English (en)
Chinese (zh)
Inventor
陈千一
章珈彬
江俊
赵圣宇
陈鑫
曹继来
Original Assignee
合肥美的电冰箱有限公司
合肥华凌股份有限公司
美的集团股份有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 合肥美的电冰箱有限公司, 合肥华凌股份有限公司, 美的集团股份有限公司 filed Critical 合肥美的电冰箱有限公司
Publication of WO2024011964A1 publication Critical patent/WO2024011964A1/fr

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects

Definitions

  • the present application relates to the field of silencer equipment, specifically, to a silencer.
  • the traditional approach is to stick porous materials such as sound-absorbing cotton on the walls of ventilation ducts.
  • the thickness of the sound-absorbing cotton is limited, resulting in limited noise reduction capabilities.
  • designing acoustic metamaterials near the air inlet and outlet of the ventilation system can achieve a noise reduction effect of 1-3dB.
  • the noise reduction amplitude will also fluctuate due to changes in the size of the vents.
  • designing resonant cavities on the side walls of waveguides has been widely used. Its noise reduction effect is generally measured by transmission loss, which consists of two parts: reflection and sound absorption.
  • a single 1/4-wavelength tube is used to reduce noise at a certain frequency point. You can increase the size of the 1/4-wavelength tube.
  • the cross-sectional area increases the transmission loss, but the transmission loss is mainly contributed by reflection. The reflected sound waves may radiate outward from other locations, which is not conducive to noise reduction.
  • This application aims to solve at least one of the technical problems existing in the prior art.
  • one purpose of this application is to propose a muffler that can greatly improve the noise reduction effect through the cooperation of a waveguide and two sound absorbing tubes and reflecting tubes with different cross-sectional areas.
  • the muffler includes: a waveguide, a sound wave inlet is provided on the waveguide; a sound absorption tube and a reflection tube, the sound absorption tube and the reflection tube are along the length direction of the wave guide Arranged and connected to the waveguide, the sound-absorbing tube is arranged close to the sound wave inlet of the waveguide relative to the reflection tube.
  • Both the reflection tube and the sound-absorbing tube are 1/4 wavelength tubes, so The cross-sectional area of the reflection tube is larger than the cross-sectional area of the sound-absorbing tube.
  • the muffler by arranging sound absorbing tubes and reflecting tubes with different cross-sectional areas and both being 1/4 wavelength tubes on the waveguide, it can ensure good ventilation and heat dissipation and at the same time bring about better reduction. Secondly, since the acoustic boundary within the waveguide remains unchanged, the prediction accuracy of the noise reduction effect is high, which is conducive to the forward design of noise reduction. Moreover, by designing two 1/4-wavelength tubes at the same frequency point, the transmission loss at the target frequency can be higher than 10dB, and sound absorption plays a major role, with the sound absorption coefficient being above 0.9.
  • both the sound-absorbing tube and the reflecting tube are folded tubes.
  • the folded tube is bent to form multiple tube parts, and the multiple tube parts are connected in sequence, and an angle is formed between any two adjacent tube parts.
  • the included angle ranges from 0 to 90 degrees.
  • any two adjacent tube parts are parallel to each other and disposed closely adjacent to each other.
  • the number of tube parts formed by bending the sound absorbing tube and the reflecting tube is different; or, the number of tube parts formed by bending the sound absorbing tube and the reflecting tube is different.
  • the number of parts is the same.
  • a plurality of the tube parts are arranged side by side and formed with an arrangement plane, and the arrangement plane is arranged along the horizontal direction or along the vertical direction.
  • a plurality of the tube parts are arranged side by side and form an arrangement plane, and the arrangement plane is inclined relative to the horizontal plane.
  • the distance between the sound-absorbing tube and the reflecting tube is 50 mm to 300 mm.
  • the cross-sectional area of the sound absorbing tube and the reflecting tube is 1.5% to 30% of the cross-sectional area of the waveguide.
  • the cross-sectional profile of the waveguide, the sound-absorbing tube, and the reflecting tube is at least any one of a circle, a square, and a rectangle.
  • the wall thickness of the waveguide, the sound absorbing tube and the reflecting tube is 1 to 4 mm.
  • the sound absorbing tube and the reflecting tube are arranged in multiple groups along the length of the waveguide, and each group includes one sound absorbing tube and one reflecting tube.
  • Figure 1 is a schematic diagram of a silencer in an embodiment of the present application
  • Figure 2 is a bottom view of the silencer in the embodiment of the present application.
  • Figure 3 is a schematic three-dimensional structural diagram of the muffler in the embodiment of the present application.
  • the muffler 100 according to the embodiment of the present application is described below with reference to FIGS. 1-3 .
  • the silencer 100 can be used in a variety of devices that require noise reduction.
  • the silencer 100 can be used in an air duct machine.
  • the silencer 100 is connected to the air outlet of the air duct machine to achieve silencing of the air duct machine.
  • Noise reduction
  • the muffler 100 can also be applied to the compressor compartment of a refrigerator to eliminate noise generated by the compressor.
  • this is just an example, and the silencer 100 can also be used in other equipment that requires noise elimination and noise reduction, which will not be described again here.
  • a muffler 100 includes: a waveguide 10 , a sound absorbing tube 20 , and a reflecting tube 30 .
  • the waveguide 10 is provided with a sound wave inlet (not shown in the figure); the sound-absorbing tube 20 and the reflecting tube 30 are arranged along the length of the waveguide 10 and are connected to the outer wall of the waveguide 10 to ensure that they will not affect normal Heat dissipation effect; the sound-absorbing tube 20 is arranged close to the sound wave inlet of the waveguide 10 relative to the reflecting tube 30. Both the reflecting tube 30 and the sound-absorbing tube 20 are 1/4 wavelength tubes.
  • the cross-sectional area of the reflecting tube 30 is larger than the cross-sectional area of the sound-absorbing tube 20. Sectional area.
  • the waveguide 10 can provide ventilation and heat dissipation, control the sound propagation path, and cooperate with the first resonant cavity 20 and the second resonant cavity 30 to reduce noise.
  • the cross-sectional area of the sound-absorbing tube 20 is relatively small, its reflection coefficient is relatively low, and its sound absorption coefficient is relatively high. It mainly plays a sound absorption role and has a relatively good sound absorption effect.
  • the cross-sectional area of the reflection tube 30 is relatively large, its reflection coefficient is relatively high, and its sound absorption coefficient is relatively low. It mainly plays a reflection role and has a relatively good effect of reflecting sound waves.
  • the sound wave enters from the sound wave inlet of the waveguide 10, first passes through the sound absorbing tube 20, and then radiates outward through the reflecting tube 30.
  • the sound absorption coefficient can be changed.
  • the reflection tube 30 and the sound-absorbing tube 20 are both 1/4-wavelength tubes.
  • the high-order resonance frequency of the 1/4-wavelength tube can also exert a relatively obvious noise reduction effect within 6400 Hz.
  • the muffler 100 by arranging the sound absorbing tube 20 and the reflecting tube 30 with different cross-sectional areas and both being 1/4 wavelength tubes on the waveguide 10, it can ensure good ventilation and heat dissipation while ensuring good ventilation and heat dissipation.
  • the noise reduction effect is relatively good.
  • the acoustic boundary within the waveguide 10 is unchanged (simple and stable), the prediction accuracy of the noise reduction effect is high, which is conducive to the forward design of noise reduction.
  • the transmission loss at the target frequency can be higher than 10dB, and sound absorption plays a major role, with the sound absorption coefficient being above 0.9.
  • both the sound absorbing tube 20 and the reflecting tube 30 are folded tubes.
  • the required lengths of the sound-absorbing tube 20 and the reflecting tube 30 are relatively long.
  • the overall structure of the silencer 100 is made more compact and has a smaller size. With its smaller volume and greater space utilization, it can adapt to different space structures, has more flexible applications and a wider range of applications.
  • the folded tube is bent to form multiple tube parts 201, and an included angle is formed between any two tube parts 201, and the included angle ranges from 0 to 90 degrees.
  • the lower the target frequency the longer the length of the sound-absorbing tube 20 and the reflecting tube 30. Therefore, the number of tube parts 201 formed by bending the folded tubes can be larger, which can greatly shorten the sound absorption and emission effects while ensuring better sound absorption and emission effects.
  • the overall length of the wavelength tube saving a lot of space.
  • plural means two or more.
  • the included angle formed between any two tube parts 201 can be any value among 0 degrees, 10 degrees, 30 degrees, 45 degrees, 60 degrees, 80 degrees, and 90 degrees.
  • the included angle is not limited to the above.
  • it can also be other values in the range of 0 to 90 degrees, which can be set specifically according to the situation.
  • any two adjacent tube parts 201 are parallel to each other and disposed closely adjacent to each other. That is to say, two adjacent tube parts 201 are arranged in parallel and closely contact each other, which ensures a more compact structure between the multiple tube parts 201 and saves space.
  • the number of tube parts 201 formed by bending the sound absorbing tube 20 and the reflecting tube 30 is different; or, the number of tube parts 201 formed by bending the sound absorbing tube 20 and the reflecting tube 30 is different.
  • the number of 201 is the same.
  • the sound-absorbing tube 20 is bent to form three tube parts 201
  • the reflection tube 30 is bent to form two tube parts 201 .
  • the number of tube parts 201 formed by bending the sound-absorbing tube 20 is three
  • the number of tube parts 201 formed by bending the reflection tube 30 is three. This is just an example.
  • the number of tube parts 201 formed by the sound-absorbing tube 20 is The quantity and the number of tube portions 201 formed by the reflective tube 30 are not limited to this, and can also be other quantities, which will not be described again here.
  • each group of sound-absorbing tubes 20 and reflecting tubes 30 is the same, and the sound-absorbing tubes 20 and reflecting tubes 30 of the same length target the same target sound frequency band for noise reduction. Therefore, since the sound-absorbing tubes 20 and the reflecting tubes 30 have the same Different diameters of the tubes 30 can achieve higher space utilization and reduce the volume of the silencer 100.
  • the length and number of each tube portion 201 after bending can be the same or different.
  • the length and number of the tube portions 201 are not the same. It will affect the noise reduction ability.
  • multiple tube portions 201 are arranged side by side and formed with an arrangement plane, and the arrangement plane is arranged along the horizontal direction or along the vertical direction.
  • a plurality of tube portions 201 are arranged side by side on a horizontal plane parallel to the tube length direction of the waveguide 10 .
  • the plurality of tube portions 201 are arranged side by side on a vertical plane parallel to the tube length direction of the waveguide 10 .
  • the bending directions of the sound absorbing tube 20 and the reflecting tube 30 can be specifically set according to the situation, and the plurality of tube parts 201 can be located in the vertical plane or the horizontal plane, and the sound absorbing tube 20 and The ability of the reflection tube 30 to be bent in any direction in space provides more possibilities for the appearance design of the silencer 100 , which is not limited to the fact that the tube portion 201 of the sound-absorbing tube 20 and the reflection tube 30 is arranged parallel to the waveguide 10 On the tube wall, there can be more design combinations according to the different cross-sections of the waveguide 10; at the same time, the side-by-side design of the tube parts 201 makes the structure of the entire noise reduction device 100 more compact, which not only makes the noise reduction device 100 smaller The volume also provides greater space utilization, allowing the noise reduction device 100 to be suitable for more equipment structures.
  • multiple tube portions 201 are arranged side by side and form an arrangement plane, and the arrangement plane is inclined relative to the horizontal plane.
  • the arrangement plane formed by the plurality of tube parts 201 can be arranged at an angle, which can also achieve the effect of making the structure more compact and occupying less space.
  • the distance between the sound absorbing tube 20 and the reflecting tube 30 is 50 mm to 300 mm. That is to say, the distance between the sound absorbing tube 20 and the reflecting tube 30 is any value among 50mm, 80mm, 100mm, 150mm, 180mm, 200mm, 250mm, 280mm, and 300mm. Of course, it can also be other values in the range of 50mm to 300mm. , I won’t go into details here.
  • the distance between the sound-absorbing tube 20 and the reflection tube 30 is within 50 mm to 300 mm and has no impact on the targeted noise reduction sound frequency band; when the distance between the sound-absorbing tube 20 and the reflection tube 30 exceeds the range, sound will be transmitted out of the wavelength tube. 10.
  • the cross-sectional area of the sound absorbing tube 20 and the reflecting tube 30 is 1.5% to 30% of the cross-sectional area of the waveguide 10 .
  • the diameter of the sound-absorbing tube 20 should be the diameter when the sound absorption coefficient is 0.5
  • the diameter of the reflective tube 30 should be the diameter of the 1/4-wavelength tube when the transmittance is the lowest and the reflectivity is high. diameter size, each group of mufflers formed at this time has the best noise reduction ability; the optimal diameter range of the two is that the cross-sectional area of the sound-absorbing tube 20 and the reflecting tube 30 is the cross-sectional area of the waveguide 10 1.5% to 30%.
  • the cross-sectional area of the sound absorbing tube 20 and the reflecting tube 30 can be 1.5%, 2%, 3%, 5%, 10%, 15%, 20%, 30% of the cross-sectional area of the waveguide 10 Any value in %, of course, can also be other values within the range. I will not go into details here. The final value is subject to the design requirements of the waveguide diameter.
  • the cross-sectional profile of the waveguide 10 , the sound absorbing tube 20 and the reflecting tube 30 is at least any one of a circle, a square and a rectangle.
  • the cross-sectional shape of the muffler 100 does not affect the noise reduction capability of the muffler 100. Therefore, cross-sectional designs of different shapes provide more appearance design possibilities for the muffler 100. Therefore, the waveguide 10 and the sound-absorbing tube
  • the cross-sectional contours of 20 and reflector tube 30 can be circular, square or rectangular.
  • the shape of the openings of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 30 is the same as the shape of the cross-sectional profile of the pipes.
  • cross-sectional profiles of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 3 can also be configured in other shapes, such as regular hexagons, triangles, etc., which will not be described again here.
  • the wall thickness of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 30 is 1 to 4 mm. That is to say, the wall thickness of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 30 can be any value among 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.5mm, 3.0mm, 3.5mm, and 4.0mm. , of course, it can also be other values, which will not be described one by one here.
  • the sound absorbing tubes 20 and the reflecting tubes 30 are arranged in multiple groups along the length of the waveguide 10 , and each group includes one sound absorbing tube 20 and one reflecting tube 30 .
  • the sound-absorbing tube 20 and the reflecting tube 30 are composed of acoustic metamaterial 1/4 wavelength tube needles, the acoustic metamaterial has extremely high sound absorption coefficient and extremely low transmittance, and can achieve a specific sound frequency band.
  • the combination of multiple sets of sound absorption tubes 20 and reflection tubes 30 can achieve targeted noise reduction for a variety of sound frequency bands within the range.
  • the 1/4 wavelength tube has more high-order noise within 6400Hz. The resonance frequency point can achieve good noise reduction effect in the range of 6400Hz.
  • the muffler 100 includes: a waveguide 10 , a sound absorbing tube 20 , and a reflecting tube 30 .
  • the waveguide 10 is provided with an acoustic inlet.
  • the sound-absorbing tube 20 and the reflecting tube 30 are arranged along the length of the waveguide 10 and are connected with the outer wall of the waveguide 10.
  • the sound-absorbing tube 20 is arranged close to the air inlet of the waveguide 10 relative to the reflecting tube 30.
  • the reflecting tube 30 and The sound absorbing tubes 20 are all 1/4 wavelength tubes, and the cross-sectional area of the reflecting tube 30 is larger than that of the sound absorbing tube 20 .
  • Both the sound absorbing tube 20 and the reflecting tube 30 are folded tubes.
  • the sound-absorbing tube 20 is bent to form three tube parts 201, and the reflection tube 30 is bent to form two tube parts 201. Any two tube parts 201 are parallel to each other and arranged closely adjacent to each other.
  • the three tube parts 201 of the sound absorbing tube 20 and the two tube parts 201 of the reflecting tube 30 are arranged side by side on a horizontal plane parallel to the tube length direction of the waveguide 10 .
  • the distance between the sound absorbing tube 20 and the reflecting tube 30 is 50 mm.
  • the cross-sectional area of the sound-absorbing tube 20 is 1.5% of the cross-sectional area of the waveguide 10
  • the cross-sectional area of the sound-absorbing tube 20 is 3.5% of the cross-sectional area of the waveguide 10 .
  • the cross-sectional profiles of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 30 are circular.
  • the tube wall thickness of the waveguide 10, the sound absorbing tube 20 and the reflecting tube 30 is 2 mm.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Exhaust Silencers (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)

Abstract

Silencieux (100), comprenant : un tube de guide d'ondes (10), un tube d'absorption de son (20) et un tube de réflexion (30), le tube de guide d'ondes (10) étant pourvu d'une entrée d'onde sonore. Le tube d'absorption de son (20) et le tube de réflexion (30) sont agencés dans la direction de la longueur du tube de guide d'ondes (10) et sont en communication avec le tube de guide d'ondes (10), le tube d'absorption de son (20) étant disposé plus près de l'entrée d'ondes sonores du tube de guide d'ondes (10) que le tube de réflexion (30), le tube de réflexion (30) et le tube d'absorption de son (20) étant tous deux des tubes quart d'onde, et la surface de section transversale du tube de réflexion (30) étant supérieure à la surface de section transversale du tube d'absorption de son (20).
PCT/CN2023/086308 2022-07-12 2023-04-04 Silencieux WO2024011964A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202210822751.6A CN115050347A (zh) 2022-07-12 2022-07-12 消音器
CN202210822751.6 2022-07-12

Publications (1)

Publication Number Publication Date
WO2024011964A1 true WO2024011964A1 (fr) 2024-01-18

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Application Number Title Priority Date Filing Date
PCT/CN2023/086308 WO2024011964A1 (fr) 2022-07-12 2023-04-04 Silencieux

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CN (1) CN115050347A (fr)
WO (1) WO2024011964A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115050347A (zh) * 2022-07-12 2022-09-13 合肥美的电冰箱有限公司 消音器

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0704617A1 (fr) * 1994-09-02 1996-04-03 General Motors Corporation Absorbeur de son
EP1548701A1 (fr) * 2003-12-23 2005-06-29 Mark IV Systemes Moteurs (Société Anonyme) Conduit avec des attenuateurs acoustiques intégrés et son procédé de fabrication
CN106988085A (zh) * 2017-04-25 2017-07-28 青岛海尔洗衣机有限公司 一种洗衣机的降噪系统、降噪方法及洗衣机
CN211116187U (zh) * 2019-12-27 2020-07-28 三一重机有限公司 消音器机构
CN112128083A (zh) * 2020-10-30 2020-12-25 广西玉柴机器股份有限公司 一种整车空压机进气管路降噪方法及降噪波长管
CN213065077U (zh) * 2020-08-26 2021-04-27 南京林业大学 迷宫型谐振器及基于其的管道消声装置
CN113132851A (zh) * 2021-04-29 2021-07-16 维沃移动通信有限公司 电子设备
CN214370886U (zh) * 2021-01-19 2021-10-08 青岛海信日立空调系统有限公司 新风空调器
CN214998099U (zh) * 2021-05-27 2021-12-03 一汽解放汽车有限公司 一种空压机用消音器
CN115050347A (zh) * 2022-07-12 2022-09-13 合肥美的电冰箱有限公司 消音器

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0704617A1 (fr) * 1994-09-02 1996-04-03 General Motors Corporation Absorbeur de son
EP1548701A1 (fr) * 2003-12-23 2005-06-29 Mark IV Systemes Moteurs (Société Anonyme) Conduit avec des attenuateurs acoustiques intégrés et son procédé de fabrication
CN106988085A (zh) * 2017-04-25 2017-07-28 青岛海尔洗衣机有限公司 一种洗衣机的降噪系统、降噪方法及洗衣机
CN211116187U (zh) * 2019-12-27 2020-07-28 三一重机有限公司 消音器机构
CN213065077U (zh) * 2020-08-26 2021-04-27 南京林业大学 迷宫型谐振器及基于其的管道消声装置
CN112128083A (zh) * 2020-10-30 2020-12-25 广西玉柴机器股份有限公司 一种整车空压机进气管路降噪方法及降噪波长管
CN214370886U (zh) * 2021-01-19 2021-10-08 青岛海信日立空调系统有限公司 新风空调器
CN113132851A (zh) * 2021-04-29 2021-07-16 维沃移动通信有限公司 电子设备
CN214998099U (zh) * 2021-05-27 2021-12-03 一汽解放汽车有限公司 一种空压机用消音器
CN115050347A (zh) * 2022-07-12 2022-09-13 合肥美的电冰箱有限公司 消音器

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