CN113470605B - Continuously adjustable sound absorption structure - Google Patents
Continuously adjustable sound absorption structure Download PDFInfo
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- CN113470605B CN113470605B CN202110649634.XA CN202110649634A CN113470605B CN 113470605 B CN113470605 B CN 113470605B CN 202110649634 A CN202110649634 A CN 202110649634A CN 113470605 B CN113470605 B CN 113470605B
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- 238000010521 absorption reaction Methods 0.000 title abstract description 43
- 238000005192 partition Methods 0.000 claims abstract description 73
- 230000007423 decrease Effects 0.000 claims abstract description 13
- 238000007789 sealing Methods 0.000 claims description 2
- 230000008719 thickening Effects 0.000 claims description 2
- 238000010276 construction Methods 0.000 claims 3
- 230000000694 effects Effects 0.000 abstract description 11
- 239000000463 material Substances 0.000 description 5
- 238000013461 design Methods 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 238000010146 3D printing Methods 0.000 description 1
- 239000011358 absorbing material Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000003102 growth factor Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
Classifications
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- 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
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
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- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention discloses a continuously adjustable sound absorption structure, and belongs to the technical field of medium-low frequency vibration reduction and noise reduction. Comprises a semi-cylindrical cavity, a rotary baffle plate and a closed top plate; the top surface of the semi-cylindrical chamber is partially closed by a closed top plate, a lockable rotating device is connected to the first end of the rotating partition plate, wall gaps are formed between the second end of the rotating partition plate and the wall surface of the semi-cylindrical chamber, and end surface gaps are formed between the two sides of the rotating partition plate and the two end surfaces of the semi-cylindrical chamber; the semi-cylindrical cavity is divided into a rigid back cavity by the rotary partition plate and the closed top plate; when the rotary partition board rotates, the wall gap increases with the increase of the volume of the rigid back cavity and decreases with the decrease of the volume of the rigid back cavity. The invention has compact structure, operation proposal and excellent sound absorption effect, and has wide application prospect in the middle-low frequency absorption of complex noise environment and scene change condition.
Description
Technical Field
The invention belongs to the technical field of medium-low frequency vibration reduction and noise reduction, and particularly relates to a continuously adjustable sound absorption structure.
Background
Conventional sound absorbing materials and structures achieve good sound absorption within a particular frequency band, however, once the structural design is complete, the corresponding sound absorption band is established. After the application scene is slightly changed, the original structure is difficult to continue to be applicable. The problems of poor replaceability among different scenes, low structural reusability and the like restrict the practical application of conventional sound absorption materials and structures. Thus, it is becoming necessary to develop a continuously adjustable sound absorbing structure.
In recent years, a great deal of researches are carried out on adjustable sound absorption structures by mass students, and the two main categories are that the sound absorption structures are realized by utilizing an active mode of an electromagnetic structure, and the other category is realized by utilizing a passive mode of a mechanical structure. For the active adjusting mode by utilizing an electromagnetic structure, the film tension of the film type resonance unit is changed to realize a better sound absorption adjusting effect in a wider frequency range, the adopted film material is mainly made of a piezoelectric material or a magnetorheological elastomer, the preparation of the material and an active control system are relatively complex, and further research and simplification are still needed in practical application. Compared with the research of realizing adjustable sound absorption by using an electric or magnetic mode, the research of adopting a passive mode of structural control is relatively much less. The structural control mode mainly utilizes the traditional Helmholtz resonant cavity, and realizes the adjustment of the sound absorption frequency band by independently changing the back cavity of the resonant structure or changing the opening size of the resonant cavity, and the adjustment mode can independently adjust the acoustic resistance or the acoustic impedance, but cannot realize the synchronous adjustment of the acoustic resistance and the acoustic impedance, so that perfect sound absorption is difficult to realize. There are also studies on adjusting acoustic resistance and acoustic resistance by different structures, respectively, and although a very good adjustable sound absorption effect can be obtained, the practicality is limited due to the complicated adjusting structure or inconvenient operation.
Disclosure of Invention
In order to solve the problems, the invention aims to provide a continuously adjustable sound absorption structure which has compact structure, simple and convenient operation, excellent sound absorption effect in a medium-low frequency range and adjustable parameters.
The invention is realized by the following technical scheme:
The invention discloses a continuously adjustable sound absorption structure, which comprises a semi-cylindrical cavity, a rotary baffle plate and a closed top plate, wherein the semi-cylindrical cavity is formed in the rotary baffle plate; the top surface of the semi-cylindrical chamber is partially closed by a closed top plate, a lockable rotating device is connected to the first end of the rotating partition plate, wall gaps are formed between the second end of the rotating partition plate and the wall surface of the semi-cylindrical chamber, and end surface gaps are formed between the two sides of the rotating partition plate and the two end surfaces of the semi-cylindrical chamber; the semi-cylindrical cavity is divided into a rigid back cavity by the rotary partition plate and the closed top plate; when the rotary partition board rotates, the wall gap increases with the increase of the volume of the rigid back cavity and decreases with the decrease of the volume of the rigid back cavity.
Preferably, the first end of the rotating partition is parallel to the rotation axis of the semi-cylindrical chamber and is offset toward the closed ceiling side.
Preferably, the first end of the rotating partition is collinear with the axis of rotation of the semi-cylindrical chamber, the radius of the wall of the semi-cylindrical chamber increasing from the closed side to the open side.
Preferably, the outer wall of the semi-cylindrical chamber is provided with angle indicating means.
Further preferably, the angle indicating device comprises an angle adjusting pointer and an angle adjusting disc, one end of the angle adjusting pointer is connected with the first end of the rotary partition plate, a plurality of equally-divided saw teeth are arranged on the angle adjusting disc, and the needle end of the angle adjusting pointer can be embedded into the saw teeth.
Preferably, the numerical difference between the wall gap and the end gap is less than or equal to + -30%.
Preferably, the distance between the two end faces of the semi-cylindrical chamber increases from the closed side to the open side.
Preferably, the wall gap is 0.2-3 mm.
Preferably, the second end of the rotating partition is shaped to match the wall surface of the semi-cylindrical chamber.
Preferably, the second end of the rotating partition is provided with a thickening.
Compared with the prior art, the invention has the following beneficial technical effects:
According to the continuously adjustable sound absorption structure, wall gaps and end face gaps exist between the semi-cylindrical cavity and the rotary partition plate, the top surface of the semi-cylindrical cavity is partially sealed through the sealing top plate and surrounds the semi-cylindrical cavity and the rotary partition plate to form a rigid back cavity, the width of the wall gaps and the volume of the rigid back cavity are adjusted through rotation of the rotary partition plate, synchronous regulation and control of sound resistance and sound resistance of the sound absorption structure are achieved, the sound resistance and air resistance are kept in a perfectly matched state all the time, and continuously adjustable sound absorption is achieved in a medium-low frequency range. After the original application scene changes, the novel application scene can be adapted only by adjusting the rotation angle of the rotary partition plate, and the utilization rate is improved. Meanwhile, compared with an active control mode adopting an electromagnetic structure, the method not only omits material processing with complex process, but also omits a complicated control system. The invention has compact structure, operation proposal and excellent sound absorption effect, and has wide application prospect for middle-low frequency absorption of complex noise environment and scene change condition.
Further, the first end of the rotary partition plate is parallel to the rotary shaft of the semi-cylindrical chamber and is offset to the side of the closed top plate, and by the eccentric design, the effect that the wall gap is increased along with the increase of the volume of the rigid back cavity and is reduced along with the decrease of the volume of the rigid back cavity is realized.
Further, the first end of the rotary partition plate is collinear with the rotary shaft of the semi-cylindrical chamber, the radius of the wall surface of the semi-cylindrical chamber increases gradually from the closed side to the open side, through the design, the effect that the wall surface gap increases along with the increase of the volume of the rigid back cavity and decreases along with the decrease of the volume of the rigid back cavity is achieved, and the manufacturing and the installation are convenient.
Further, the outer wall of the semi-cylindrical cavity is provided with an angle indicating device, so that the angle adjustment is convenient.
Further, by the angle adjusting pointer and the angle adjusting disk, the angle adjustment can be accurately realized, and the structure can be well locked after the needle end of the pointer is embedded into the saw teeth.
Further, the numerical difference between the wall gap and the end face gap is less than or equal to +/-30%, so that the acoustic resistance of the whole structure is convenient to adjust.
Further, the distance between the two end faces of the semi-cylindrical cavity increases gradually from the closed side to the opening side, so that the wall gap width and the end face gap width can be increased or reduced at the same time, and acoustic resistance adjustment of the whole structure is facilitated.
Further, the wall gap is 0.2-3 mm, the gap width is too large, so that the acoustic resistance is too small, the dissipation of acoustic energy in the gap is insufficient, and the sound absorption coefficient is small; too small a gap width will make the reflection of sound wave severe, and the sound wave is difficult to enter the micro-gap to be dissipated.
Further, the shape of the second end part of the rotary partition plate is matched with the shape of the wall surface of the semi-cylindrical cavity, the size of the micro-slit is uniform, and the sound absorption effect is good.
Further, the second end part of the rotary partition plate is provided with a thickened part, so that the larger rigid back cavity volume can be ensured under the condition that the thickness of the rotary partition plate is unchanged, and the low-frequency sound absorption is realized more favorably.
Drawings
FIG. 1 is a schematic diagram of the overall structure of the present invention;
FIG. 2 is a schematic front view of the present invention;
FIG. 3 is a schematic cross-sectional view of the present invention along the z-y plane;
FIG. 4 is a graph of the sound absorption coefficient of the present invention at different angles;
fig. 5 is a sound absorbing cloud at different angles according to the present invention.
In the figure: 1-semi-cylindrical chamber, 2-rotary baffle, 3-thickening portion, 4-angle adjusting pointer, 5-angle adjusting disk, 6-closed top plate, 7-rotating device, 8-rigid back cavity.
Detailed Description
The invention will now be described in further detail with reference to the accompanying drawings, the content of which is to be interpreted as illustrative and not limiting:
Referring to fig. 1 and 3, the continuously adjustable sound absorbing structure of the invention comprises a semi-cylindrical chamber 1, a rotary baffle plate 2 and a closed top plate 6; the top surface of the semi-cylindrical chamber 1 is partially closed by a closed top plate 6, a lockable rotating device 7 is connected to the first end of the rotary partition plate 2, wall gaps are formed between the second end of the rotary partition plate 2 and the wall surface of the semi-cylindrical chamber 1, and end surface gaps are formed between the two sides of the rotary partition plate 2 and the two end surfaces of the semi-cylindrical chamber 1; the semi-cylindrical chamber 1 is divided into a rigid back cavity 8 by a rotary partition plate 2 and a closed top plate 6; when the rotary partition plate 2 rotates, the wall gap increases with the increase of the volume of the rigid back cavity 8, and decreases with the decrease of the volume of the rigid back cavity 8.
In actual manufacture, the semi-cylindrical chamber 1 is placed in a housing or frame, and in use, the top surface opening portion of the semi-cylindrical chamber 1 faces the direction of incidence of the sound wave.
The rotating device 7 can be a rotating shaft with two ends connected with two end surfaces of the semi-cylindrical cavity 1, and the first end of the rotating partition plate 2 is sleeved on the rotating shaft. Or hinge means provided on both end surfaces of the semi-cylindrical chamber 1. Likewise, the turning device 7 can also be provided on the closing top 6.
In a preferred embodiment of the invention, since the rotating partition 2 forms a rigid back cavity 8 in the semi-cylindrical cavity 1 with the greatest acoustic impedance effect on the structure, the radius of the semi-cylindrical cavity 1 can be determined according to the minimum frequency required for adjustable sound absorption. Simultaneously, the acoustic reactance can also be adjusted in real time by adjusting the size of the rigid back cavity 8 by rotating the rotary baffle plate 2. The acoustic resistance is mainly determined by micro-gaps formed by the second end of the rotary partition plate 2 and the semi-cylindrical cavity 1, and the two sides of the rotary partition plate 2 and the two end faces of the semi-cylindrical cavity 1, and in order to adjust the acoustic resistance by using the rotation angle, the width of the micro-gaps needs to be correspondingly changed along with the change of the rotation angle, and the acoustic resistance can be realized by adopting two schemes.
One solution is that the radius of the semi-cylindrical chamber 1 may remain unchanged when the first end of the rotating partition 2 is parallel to but not collinear with the axis of rotation of the semi-cylindrical chamber 1. When the rotation angle of the rotating partition plate 2 increases, the size of the rigid back chamber 8 decreases, the sound absorption peak moves to high frequency, the corresponding acoustic resistance should increase, and the width of the micro-slit should correspondingly decrease. Therefore, the surface acoustic resistance and the surface acoustic resistance of the structure can be independently regulated and controlled so as to enable the surface acoustic resistance and the surface acoustic resistance to be perfectly matched with air impedance at any angle, and finally, continuous adjustable perfect sound absorption is realized in a medium-low frequency range. Specifically, the first end of the rotating partition plate 2 is parallel to the rotation axis of the semi-cylindrical chamber 1, and is offset toward the closed top plate 6 side.
Alternatively, when the first end of the rotating partition plate 2 and the rotation axis of the semi-cylindrical cavity are collinear, the radius of the semi-cylindrical cavity 1 needs to be changed in real time to change the micro-slit width, so that a relatively simple vortex line can be used as the cross-sectional line of the semi-cylindrical cavity 1 instead of a semicircle. Specifically, the first end of the rotating partition plate 2 is collinear with the rotation axis of the semicylindrical chamber 1, and the radius of the wall surface of the semicylindrical chamber 1 increases from the closed side to the open side.
In a preferred embodiment of the invention, for the rotating partition 2 to have a total length that is smaller than the minimum radius of the semi-cylindrical chamber 1 or smaller than the minimum radius of the semi-cylindrical chamber 1 when the first end of the rotating partition 2 is arranged eccentrically, so that a gap exists between the first end of the rotating partition 2 and the curved wall of the semi-cylindrical chamber 1. The width of the gap has obvious influence on acoustic resistance, and the width is not too wide, otherwise, the acoustic resistance is too small, the dissipation of acoustic energy in the gap is insufficient, and the sound absorption coefficient is small; the width is too narrow, so that the sound wave is seriously reflected, the sound wave is difficult to enter the micro-seam to be dissipated, and the proper value is generally between 0.2mm and 3 mm. The thickness of the micro-slit can also directly influence the acoustic resistance, in order to ensure the larger space of the rigid back cavity 8, the thickness of the rotary partition plate 2 is unchanged, and the thickness value which is generally suitable to be selected is 1-8 mm by only adding the thickened part 3 at the second end of the rotary partition plate. In order to facilitate the rotation of the rotating partition plate 2, a certain micro-gap, namely an end surface gap, is preferably formed between two sides of the rotating partition plate 2 and two end surfaces of the semi-cylindrical chamber 1, and the width of the end surface gap is equal to that of a wall surface gap formed between the second end of the rotating partition plate 2 and the semi-cylindrical chamber 1.
In a preferred embodiment of the invention, as shown in fig. 2, in order to facilitate the angular adjustment of the rotating partition 2, an angular adjustment pointer 4 is provided on the extension of the first end of the rotating partition 2, by means of which the angular adjustment of the rotating partition can be easily achieved. In order to fix the angle of the rotary screen 2, a toothed angle adjusting disk 5 is arranged on the front face, which is distributed continuously and uniformly in circumferential direction and has a radius which corresponds to the length of the angle adjusting pointer 4, and the tooth form can be engaged with the end of the angle adjusting pointer 4. The angle adjusting pointer 4 is fixed with the rotating partition plate 2 in the circumferential direction, but can move outwards along the first end of the rotating partition plate 2 by a small amount to be separated from the angle adjusting disk 5, and after the angle adjustment is completed, the angle adjusting disk 5 can be clamped in to fix the rotating partition plate 2 at a certain angle.
In a preferred embodiment of the invention, the distance between the two end faces of the semi-cylindrical chamber 1 increases from the closed side to the open side.
In a preferred embodiment of the invention, the shape of the second end of the rotating partition 2 matches the shape of the wall of the semi-cylindrical chamber 1.
In terms of design, first, the semi-cylindrical chamber 1 is sized according to the lowest sound absorption frequency. On the basis, the radius change rule of the semi-cylindrical chamber 1 or the eccentric size of the first end of the rotary partition plate 2 is determined, parameters of the rotary partition plate 2 and the second end of the rotary partition plate 2 are obtained, and then relevant parameters of the rotary adjusting pointer 4 and the angle adjusting disk 5 are determined.
In order to ensure that the deformation of the structure during rotation is small, the rotating partition plate 2 and the angle adjusting pointer 4 need to have a certain rigidity. Meanwhile, the continuously adjustable perfect sound absorption structure can be made of metal and resin and is manufactured by 3D printing or die processing.
Examples
In this embodiment, the length of the rotating partition plate 2 is equal to or greater than 35mm 3, the total length of the rotating partition plate 2 is equal to or greater than 47.2mm, the cross-sectional line of the semi-cylindrical chamber 1 is a vortex line, the radius r=r 1 +mθ, where m=1/450 mm/° is a growth factor, and θ is a rotation angle. The width of the gap between the rotary partition plate 2 and the two end surfaces of the semi-cylindrical cavity 1 is 0.3mm, the width of the gap between the rotary partition plate 2 and the wall surface is also 0.3mm, the thickness of the rotary partition plate 2 is 2mm, and the thickness of the thickened part 3 at the second end of the rotary partition plate 2 is 4mm. The angle-adjusting disk 5 has 60 serrations, each tooth form having an angle of 3 °.
By adopting the sound absorption structure to carry out sound absorption experiments, as can be seen from fig. 4, good sound absorption coefficients can be obtained at different rotation angles. In order to more comprehensively show the effect of adjustable sound absorption, the sound absorption cloud chart is drawn in fig. 5, and it can be seen that the sound absorption peak value can be regulated and controlled in real time according to the angle in the middle-low frequency range of 300-1300 Hz, and the sound absorption peak value can reach more than 0.9, so that the sound absorption cloud chart has excellent continuous adjustable perfect sound absorption characteristics.
The foregoing is only a part of the embodiments of the present invention, and although some terms are used in the present invention, the use of other terms is not excluded. These terms are used merely for convenience of description and to explain the nature of the invention and are to be construed as any additional limitations that are not intended to depart from the spirit of the invention. The foregoing description of the invention is provided by way of example only to facilitate easy understanding, but is not intended to limit the scope of the invention to any particular embodiment or embodiment, and is to be construed as being limited thereto.
Claims (10)
1. A continuously adjustable sound absorbing structure, characterized by comprising a semi-cylindrical chamber (1), a rotary baffle (2) and a closed top plate (6); the top surface of the semi-cylindrical chamber (1) is partially sealed by a sealing top plate (6), a lockable rotating device (7) is connected to the first end of the rotating partition plate (2), a wall gap is formed between the second end of the rotating partition plate (2) and the wall surface of the semi-cylindrical chamber (1), and end surface gaps are formed between the two sides of the rotating partition plate (2) and the two end surfaces of the semi-cylindrical chamber (1); the semi-cylindrical chamber (1) is divided into a rigid back chamber (8) by the rotary partition plate (2) and the closed top plate (6); when the rotary partition plate (2) rotates, the wall gap increases along with the increase of the volume of the rigid back cavity (8), and decreases along with the decrease of the volume of the rigid back cavity (8).
2. Continuously adjustable sound absorbing construction according to claim 1, characterized in that the first end of the rotating partition (2) is parallel to the axis of rotation of the semi-cylindrical chamber (1) and offset towards the closing top plate (6) side.
3. Continuously adjustable sound absorbing construction according to claim 1, characterized in that the first end of the rotating partition (2) is collinear with the rotation axis of the semi-cylindrical chamber (1), the radius of the wall of the semi-cylindrical chamber (1) increasing from the closed side to the open side.
4. Continuously adjustable sound absorbing structure according to claim 1, characterized in that the outer wall of the semi-cylindrical chamber (1) is provided with angle indicating means.
5. The continuously adjustable sound absorbing structure according to claim 4, characterized in that the angle indicating means comprises an angle adjusting pointer (4) and an angle adjusting disc (5), one end of the angle adjusting pointer (4) is connected with the first end of the rotating partition plate (2), the angle adjusting disc (5) is provided with a plurality of equally divided saw teeth, and the needle end of the angle adjusting pointer (4) can be embedded into the saw teeth.
6. The continuously adjustable sound absorbing structure of claim 1, wherein the wall gap and the end gap differ in value by less than or equal to ± 30%.
7. Continuously adjustable sound absorbing structure according to claim 1, characterized in that the distance between the two end faces of the semi-cylindrical chamber (1) increases along the closed side to the open side.
8. The continuously adjustable sound absorbing structure of claim 1, wherein the wall gap is 0.2-3 mm.
9. Continuously adjustable sound absorbing structure according to claim 1, characterized in that the shape of the second end of the rotating partition (2) matches the shape of the wall of the semi-cylindrical chamber (1).
10. Continuously adjustable sound absorbing construction according to claim 1, characterized in that the second end of the rotating partition (2) is provided with a thickening (3).
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| CN202110649634.XA CN113470605B (en) | 2021-06-10 | 2021-06-10 | Continuously adjustable sound absorption structure |
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| CN202110649634.XA CN113470605B (en) | 2021-06-10 | 2021-06-10 | Continuously adjustable sound absorption structure |
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| CN113470605B true CN113470605B (en) | 2024-05-24 |
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| CN113993031B (en) * | 2021-11-10 | 2023-07-14 | 歌尔科技有限公司 | Sound generating device, calibration method of sound generating device and sound generating unit |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05257482A (en) * | 1992-03-16 | 1993-10-08 | Hitachi Ltd | Silencer for intake duct |
| US5283398A (en) * | 1989-12-26 | 1994-02-01 | Tsuchiya Mfg. Co., Ltd. | Resonator type silencer |
| JPH0634109U (en) * | 1992-09-30 | 1994-05-06 | 株式会社土屋製作所 | Variable resonance silencer |
| JPH0658151U (en) * | 1992-06-30 | 1994-08-12 | 株式会社土屋製作所 | Variable resonance silencer |
| CA2931869A1 (en) * | 2015-06-03 | 2016-12-03 | Epic Metals Corporation | Tunable specular acoustic deck |
| CN106765678A (en) * | 2017-01-09 | 2017-05-31 | 美的集团股份有限公司 | Silencer and air-conditioning system |
| RU2643888C1 (en) * | 2017-06-14 | 2018-02-06 | Олег Савельевич Кочетов | Chamber noise suppressor |
| CN109801615A (en) * | 2018-12-12 | 2019-05-24 | 东南大学 | A kind of flexibility Helmholtz's sound is adjusted and controlled |
| CN110439653A (en) * | 2019-08-26 | 2019-11-12 | 南京工程学院 | A kind of adjustable Helmholtz noise elimination cavity of the double frequency of vehicular engine |
| CN211578366U (en) * | 2019-12-24 | 2020-09-25 | 南京林业大学 | Frequency-adjustable Helmholtz resonator |
| CN111816151A (en) * | 2020-08-05 | 2020-10-23 | 南昌航空大学 | Double-layer honeycomb-micro-perforated structure with adjustable back cavity height and design method thereof |
| KR102202129B1 (en) * | 2020-06-29 | 2021-01-12 | 오렌슈츠 주식회사 | Sound Control Device using Dial |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4251027B2 (en) * | 2003-07-14 | 2009-04-08 | トヨタ紡織株式会社 | Silencer |
-
2021
- 2021-06-10 CN CN202110649634.XA patent/CN113470605B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5283398A (en) * | 1989-12-26 | 1994-02-01 | Tsuchiya Mfg. Co., Ltd. | Resonator type silencer |
| JPH05257482A (en) * | 1992-03-16 | 1993-10-08 | Hitachi Ltd | Silencer for intake duct |
| JPH0658151U (en) * | 1992-06-30 | 1994-08-12 | 株式会社土屋製作所 | Variable resonance silencer |
| JPH0634109U (en) * | 1992-09-30 | 1994-05-06 | 株式会社土屋製作所 | Variable resonance silencer |
| CA2931869A1 (en) * | 2015-06-03 | 2016-12-03 | Epic Metals Corporation | Tunable specular acoustic deck |
| CN106765678A (en) * | 2017-01-09 | 2017-05-31 | 美的集团股份有限公司 | Silencer and air-conditioning system |
| RU2643888C1 (en) * | 2017-06-14 | 2018-02-06 | Олег Савельевич Кочетов | Chamber noise suppressor |
| CN109801615A (en) * | 2018-12-12 | 2019-05-24 | 东南大学 | A kind of flexibility Helmholtz's sound is adjusted and controlled |
| CN110439653A (en) * | 2019-08-26 | 2019-11-12 | 南京工程学院 | A kind of adjustable Helmholtz noise elimination cavity of the double frequency of vehicular engine |
| CN211578366U (en) * | 2019-12-24 | 2020-09-25 | 南京林业大学 | Frequency-adjustable Helmholtz resonator |
| KR102202129B1 (en) * | 2020-06-29 | 2021-01-12 | 오렌슈츠 주식회사 | Sound Control Device using Dial |
| CN111816151A (en) * | 2020-08-05 | 2020-10-23 | 南昌航空大学 | Double-layer honeycomb-micro-perforated structure with adjustable back cavity height and design method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 低频大宽带声学超结构的多阶共振高效吸声机理;刘波涛等;西安交通大学学报;20200831;第第54卷卷(第第8期期);第149-156页 * |
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