CN212276806U - High-performance noise elimination structure - Google Patents
High-performance noise elimination structure Download PDFInfo
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- CN212276806U CN212276806U CN202021491624.5U CN202021491624U CN212276806U CN 212276806 U CN212276806 U CN 212276806U CN 202021491624 U CN202021491624 U CN 202021491624U CN 212276806 U CN212276806 U CN 212276806U
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Abstract
The utility model relates to the technical field of acoustics, in particular to a high-performance noise elimination structure, an inner cylinder body formed by splicing perforated protective panels is coaxially arranged in an outer cylinder body, the inner walls around the outer cylinder body are all provided with resonance sound absorption layers, a porous sound absorption material layer is arranged between the inner cylinder body and the resonance sound absorption layers, and the resonance sound absorption layers are formed by splicing one, two or three of a perforated plate resonance sound absorption structure, a thin plate resonance sound absorption structure and a single-cavity resonance sound absorption structure; compared with the existing resistive noise elimination structure, the structure has the noise elimination performance of a full frequency band, can realize the sound absorption characteristics of high low frequency, medium frequency and high frequency, can shorten the size of the existing noise elimination structure, improves the noise elimination quantity of the existing noise elimination structure, and has good operability and adaptability. Meanwhile, the sound absorption structure also has the advantages of replaceable materials, adjustable sound absorption structures with different properties, convenience in installation and the like.
Description
Technical Field
The utility model relates to an acoustics technical field especially relates to a high performance noise cancelling structure.
Background
In civil and industrial acoustic laboratories and noise reduction occasions, the situation that a hole needs to be formed is often met, and according to an acoustic theory, the sound insulation quantity of the component is greatly reduced by forming the hole. Often these holes require resistive sound damping channels to reduce the noise transmitted through the hole. However, the resistive silencing channel can only reduce medium-high frequency noise, and under the condition of limited field size, the silencing channel cannot be made very long, so that the requirement of noise reduction is difficult to meet; which is undesirable to those skilled in the art.
SUMMERY OF THE UTILITY MODEL
In order to solve the existing problems, the utility model discloses a high-performance noise elimination structure, which comprises an outer cylinder, a resonance sound absorption layer and an inner cylinder;
openings are formed in the left end and the right end of the outer cylinder, the inner cylinder is coaxially arranged in the outer cylinder, resonance sound absorption layers are arranged on the peripheral inner walls of the outer cylinder, and porous sound absorption material layers are arranged between the inner cylinder and the resonance sound absorption layers;
the inner cylinder body is formed by splicing perforated protective panels, and the resonance sound absorption layer is formed by splicing one, two or three of a perforated plate resonance sound absorption structure, a thin plate resonance sound absorption structure and a single-cavity resonance sound absorption structure.
In the high-performance silencing structure, the outer cylinder is a rectangular cylinder.
In the high-performance sound attenuation structure, the resonance sound absorption layers on the inner walls of the periphery of the rectangular cylinder are the same.
Foretell high performance sound-absorbing structure, wherein, resonance sound-absorbing layer includes the edge at least one first resonance sound-absorbing unit that the one end of rectangle barrel set gradually to the other end, first resonance sound-absorbing unit includes the edge perforated plate resonance sound-absorbing structure, sheet metal resonance sound-absorbing structure, perforated plate resonance sound-absorbing structure, single chamber resonance sound-absorbing structure and perforated plate resonance sound-absorbing structure that the axial direction of rectangle barrel set gradually.
The resonance sound absorption layer comprises a plurality of perforated plate resonance sound absorption structures which are sequentially arranged along the axial direction of the rectangular cylinder.
In the high-performance sound attenuation structure, the resonance sound absorption layer comprises thin plate resonance sound absorption structures which are sequentially arranged along the axial direction of the rectangular cylinder.
The resonance sound absorption layer comprises a plurality of single-cavity resonance sound absorption structures which are sequentially arranged along the axial direction of the rectangular cylinder.
In the high-performance sound attenuation structure, the resonance sound absorption layers on the peripheral side walls of the rectangular cylinder are different.
In the high-performance sound-absorbing structure, the porous sound-absorbing material layer is made of glass fiber sound-absorbing cotton, polyester fiber sound-absorbing cotton or melamine sound-absorbing cotton.
The high-performance sound attenuation structure is characterized in that the perforated protective panel has a perforation rate of more than 20%.
Above-mentioned utility model has following advantage or beneficial effect:
the utility model discloses a high-performance noise elimination structure, which is characterized in that an inner cylinder body formed by splicing perforated protective panels is coaxially arranged in an outer cylinder body, the inner walls of the periphery of the outer cylinder body are all provided with resonance sound absorption layers, and a porous sound absorption material layer is arranged between the inner cylinder body and the resonance sound absorption layers; compared with the existing resistive noise elimination structure, the structure has the noise elimination performance of a full frequency band, can realize the sound absorption characteristics of high low frequency, medium frequency and high frequency, can shorten the size of the existing noise elimination structure, improves the noise elimination quantity of the existing noise elimination structure, and has good operability and adaptability. Meanwhile, the sound absorption structure also has the advantages of replaceable materials, adjustable sound absorption structures with different properties, convenience in installation and the like.
Drawings
The invention and its features, aspects and advantages will become more apparent from a reading of the following detailed description of non-limiting embodiments with reference to the attached drawings. Like reference symbols in the various drawings indicate like elements. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1a is a schematic structural view of a resonance sound absorption layer in the embodiment of the present invention in a splicing manner A;
FIG. 1B is a schematic structural diagram of the embodiment of the present invention in which the resonant sound absorption layer is spliced in a manner of B;
fig. 1C is a schematic structural view of the resonance sound absorption layer in the embodiment of the present invention in a C-splicing manner;
fig. 1D is a schematic structural view of the resonance sound absorption layer in the embodiment of the present invention in a D-splicing manner;
fig. 2 is a cross-sectional view of a medium and high performance muffler according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a medium-high performance muffler according to an embodiment of the present invention;
fig. 4 is a schematic view of an application structure of a medium and high performance muffler according to an embodiment of the present invention;
FIG. 5 is a cross-sectional view taken at 1-1 of FIG. 4;
fig. 6 is a schematic structural view of a medium-high performance muffler in the second embodiment of the present invention;
fig. 7 is a schematic structural view of a medium-high performance muffler in the third embodiment of the present invention;
fig. 8 is a schematic structural diagram of a four-high performance muffler of an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a fifth middle high performance muffler according to an embodiment of the present invention.
Detailed Description
The utility model discloses a high-performance noise elimination structure, which comprises an outer cylinder body, a resonance sound absorption layer and an inner cylinder body; openings are formed in the left end and the right end of the outer cylinder, the inner cylinder is coaxially arranged in the outer cylinder, resonance sound absorption layers are arranged on the peripheral inner walls of the outer cylinder, and porous sound absorption material layers are arranged between the inner cylinder and the resonance sound absorption layers; the inner cylinder body is formed by splicing perforated protective panels, and the resonance sound absorption layer is formed by splicing one, two or three of a perforated plate resonance sound absorption structure 20, a thin plate resonance sound absorption structure 30 and a single-cavity resonance sound absorption structure 40; as shown in fig. 1a, when the resonant sound absorption layer is a splicing manner, the resonant sound absorption layer includes at least one first resonant sound absorption unit (only one first resonant sound absorption unit is shown in the figure, if more than two first resonant sound absorption units are provided, only two or more first resonant sound absorption units need to be spliced together), and the first resonance sound absorption unit comprises a perforated plate resonance sound absorption structure 20, a thin plate resonance sound absorption structure 30, a perforated plate resonance sound absorption structure 20, a single-cavity resonance sound absorption structure 40 and a perforated plate resonance sound absorption structure 20 which are sequentially arranged along the axial direction of the outer cylinder, namely, the resonance sound absorption layer in fig. 1a is formed by splicing three types of perforated plate resonance sound absorption structures 20, thin plate resonance sound absorption structures 30 and single-cavity resonance sound absorption structures 40, and the resonance sound absorption layer is suitable for broadband noise elimination. The resonance sound absorption layers in fig. 1B, 1c and 1d are formed by splicing one of a perforated plate resonance sound absorption structure 20, a thin plate resonance sound absorption structure 30 and a single-cavity resonance sound absorption structure 40, specifically, as shown in fig. 1B, the resonance sound absorption layers are arranged in a B arrangement mode, each resonance sound absorption layer comprises a plurality of perforated plate resonance sound absorption structures 20 which are sequentially arranged along the axial direction of the outer cylinder body, and the resonance sound absorption layers are suitable for silencing broadband noises at medium and high frequencies and mainly silencing noises at 50-200 Hz at low frequency; as shown in fig. 1C, the resonance sound absorption layer is arranged in a C-arrangement manner, and includes a plurality of thin plate resonance sound absorption structures 30 sequentially arranged along the axial direction of the outer cylinder, and the resonance sound absorption layer is suitable for silencing the middle-high frequency broadband noise and the low frequency part mainly of the 80-300 Hz noise; as shown in FIG. 1D, the resonance sound absorption layer is arranged in a D mode, the resonance sound absorption layer comprises single-cavity resonance sound absorption structures 40 which are sequentially arranged along the axial direction of the outer cylinder body, the resonance sound absorption layer is suitable for silencing medium-high frequency broadband noise, and the low frequency part is mainly 125-250 Hz noise. Of course, the resonance sound absorption layer can also be formed by splicing two of the perforated plate resonance sound absorption structure 20, the thin plate resonance sound absorption structure 30 and the single-cavity resonance sound absorption structure 40, for example, the resonance sound absorption layer is formed by splicing the perforated plate resonance sound absorption structure 20 and the thin plate resonance sound absorption structure 30, or is formed by splicing the perforated plate resonance sound absorption structure 20 and the single-cavity resonance sound absorption structure 40, or is formed by splicing the thin plate resonance sound absorption structure 30 and the single-cavity resonance sound absorption structure 40 (not shown in the figure). The high-performance silencing structure can achieve good silencing performance of low-frequency noise, medium-frequency noise and high-frequency noise under the condition of a short size, the silencing quantity of the high-performance silencing structure far exceeds that of a traditional resistive silencing channel under the condition of being equal to that of the traditional resistive silencing channel, the length of the silencing channel can be reduced in actual use, the acoustic performance of the silencing channel is improved, and meanwhile, the high-performance silencing structure can also be used as a high-performance silencer on occasions where materials do not need to enter and exit. The material and airflow channel silencer has high applicability when being used as a silencing channel and a silencer on the occasions of material and airflow channels with small sizes and high acoustic indexes.
The present invention will be further described with reference to the accompanying drawings and specific examples, which should not be construed as limiting the invention.
The first embodiment is as follows:
as shown in fig. 1a and fig. 2 to 5, the embodiment discloses a high-performance sound-absorbing structure, which can be applied to a through-wall opening of a sound-insulating structure, and specifically, the high-performance sound-absorbing structure includes an outer cylinder 10, a resonant sound-absorbing layer, and an inner cylinder 60; the outer cylinder 10 is a rectangular cylinder, openings are arranged at the left end and the right end of the outer cylinder 10, the inner cylinder 60 is coaxially arranged in the outer cylinder 10, resonance sound absorption layers are arranged on the peripheral inner walls of the outer cylinder 10, and porous sound absorption material layers 50 are arranged between the inner cylinder 60 and the resonance sound absorption layers; the inner cylinder 60 is formed by splicing perforated guard plates, and the resonance sound absorption layers on the peripheral inner walls of the rectangular cylinder are in a splicing mode A shown in figure 1a, that is, the resonance sound absorption layers on the peripheral inner walls of the rectangular cylinder (the rectangular cylinder is horizontal, the resonance sound absorption layers on the peripheral inner walls of the rectangular cylinder are respectively a resonance sound absorption layer on the upper inner wall of the rectangular cylinder, a resonance sound absorption layer on the lower inner wall of the rectangular cylinder, a resonance sound absorption layer on the front inner wall of the rectangular cylinder and a resonance sound absorption layer on the rear inner wall of the rectangular cylinder) all comprise at least one first resonance sound absorption unit (only one first resonance sound absorption unit is shown in the figure, if more than two first resonance sound absorption units are arranged, only two or more first resonance sound absorption units need to be spliced together), the first resonance sound absorption unit comprises a perforated plate resonance sound absorption structure 20, a thin plate resonance sound absorption structure 30, a perforated plate resonance sound absorption structure 20, a single-cavity resonance sound absorption structure 40 and a perforated plate resonance sound absorption structure 20 which are sequentially arranged along the axial direction of the rectangular cylinder; the perforated plate resonance sound absorption structure 20 consists of a perforated plate and a rear cavity, and can absorb low-frequency and medium-frequency noise; this sheet metal resonance sound absorbing structure 30 comprises sheet metal and cavity at rear portion, it can reduce the low frequency, the intermediate frequency noise, this single chamber resonance sound absorption can reduce the low frequency especially single frequency noise, this porous sound absorbing material layer 50 can reduce the intermediate frequency, the high frequency noise, this high performance sound absorbing structure is owing to synthesized porous sound absorbing material layer 50, perforated plate resonance sound absorbing structure 20, the principle of sheet metal resonance sound absorbing structure 30 and single chamber resonance sound absorbing structure 40, can realize the low frequency, the intermediate frequency, the equal stronger sound absorbing characteristic of high frequency, be applicable to the broadband noise elimination. The high noise elimination volume can be met under the condition of small size, and simultaneously, under the condition of the same length, the noise elimination volume of the noise elimination device is far beyond that of a traditional noise elimination structure. Can be used for replacing the traditional silencing channel and the silencer. After the high-performance silencing structure is adopted, the size of the silencing structure can be reduced, the silencing quantity of the silencing structure is enhanced, the application range is expanded, and the wide applicability of a silencing channel and a silencer is improved.
The cavity 70 in the inner cylinder 60 is a material or air flow passage, and the transmitted noise can be reduced under the condition that the material or the air flow is allowed to pass through.
In a preferred embodiment of the present invention, the porous sound-absorbing material layer 50 is made of glass fiber sound-absorbing cotton, polyester fiber sound-absorbing cotton or melamine sound-absorbing cotton.
In a preferred embodiment of the present invention, the perforated protective panel has a perforation rate greater than 20%.
Example two:
as shown in fig. 1B and fig. 6, the present embodiment is substantially the same as the first embodiment, and the difference is that each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder in the present embodiment is a B-splicing manner shown in fig. 1B, that is, each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder includes a plurality of perforated plate resonant sound absorption structures 20 sequentially arranged along the axial direction of the rectangular cylinder, since the perforated plate resonant sound absorption structures 20 can absorb low-frequency and medium-frequency noise, the porous sound absorption material layer 50 can reduce medium-frequency and high-frequency noise, the high-performance sound absorption structure combines the principles of the porous sound absorption material layer 50 and the perforated plate resonant sound absorption structure 20, can realize strong sound absorption characteristics of low frequency, medium-frequency and high frequency, and is particularly suitable for medium-frequency broadband noise, the low frequency part is mainly noise-attenuated by 50 to 200Hz, and since the resonant, therefore, the preparation is more convenient, thereby reducing the cost.
Example three:
as shown in fig. 1C and fig. 7, the present embodiment is substantially the same as the first embodiment, and the difference is that each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder in the present embodiment is a C-splicing manner shown in fig. 1C, that is, each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder includes a plurality of thin plate resonant sound absorption structures 30 sequentially arranged along the axial direction of the rectangular cylinder, because the thin plate resonant sound absorption structures 30 can reduce low-frequency and medium-frequency noise, and the porous sound absorption material layer 50 can reduce medium-frequency and high-frequency noise, the high-performance sound absorption structure integrates the principles of the porous sound absorption material layer 50 and the thin plate resonant sound absorption structure 30, can realize strong sound absorption characteristics of low frequency, medium frequency, and high frequency, and is particularly suitable for medium-frequency broadband noise, and the low-frequency part is mainly; and because the resonance sound absorption layer of this embodiment structure is single, consequently it is more convenient to prepare to the cost is reduced.
Example four:
as shown in fig. 1D and fig. 8, the present embodiment is substantially the same as the first embodiment, and the difference is that each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder in the present embodiment is a D-splicing manner shown in fig. 1D, that is, each resonant sound absorption layer on the peripheral inner wall of the rectangular cylinder includes a plurality of single-cavity resonant sound absorption structures 40 sequentially arranged along the axial direction of the rectangular cylinder, because the single-cavity resonant sound absorption structure 40 can reduce low-frequency, particularly single-frequency noise, and the porous sound absorption material layer 50 can reduce medium-frequency, high-frequency noise, the high-performance sound absorption structure integrates the principles of the porous sound absorption material layer 50 and the single-cavity resonant sound absorption structure 40, can realize sound absorption characteristics with strong low-frequency, medium-frequency, and high-frequency, and is particularly suitable for medium-high-frequency broadband noise, and the low-frequency; and because the resonance sound absorption layer of this embodiment structure is single, consequently it is more convenient to prepare to the cost is reduced.
Example five:
as shown in fig. 1a to 1D and fig. 9, this embodiment is substantially the same as the first embodiment, and the difference is only that the resonance sound absorption layers on the inner walls around the rectangular cylinder in this embodiment (the rectangular cylinder is horizontal, the resonance sound absorption layers on the inner walls around the rectangular cylinder are respectively the resonance sound absorption layer on the inner wall at the upper part of the rectangular cylinder, the resonance sound absorption layer on the inner wall at the lower part of the rectangular cylinder, the resonance sound absorption layer on the inner wall at the front part of the rectangular cylinder, and the resonance sound absorption layer on the inner wall at the rear part of the rectangular cylinder) are different, specifically, the resonance sound absorption layer on the inner wall at the upper part of the rectangular cylinder is a splicing mode, the resonance sound absorption layer on the inner wall at the lower part of the rectangular cylinder is a splicing mode, the resonance sound absorption layer at the front part of the rectangular cylinder is B splicing, the embodiment integrates the advantages of the splicing mode A, the splicing mode B, the splicing mode C and the splicing mode D, can realize the sound absorption characteristics of high low frequency, medium frequency and high frequency, is suitable for broadband noise elimination, is particularly suitable for noise elimination of which the medium-high frequency is broadband noise and the low-frequency part is mainly 50-300 Hz.
Here, need explain, in the utility model discloses in, can be perforated plate resonance sound absorbing structure in the resonance sound absorbing layer, sheet metal resonance sound absorbing structure, one of them, two kinds or three kinds of independent assortment concatenations concatenation in the single chamber resonance sound absorbing structure, each resonance sound absorbing layer that is located rectangle barrel inner wall all around also can be by different or the same resonance sound absorbing layer independent assortment to be suitable for the occasion that different acoustics required.
Those skilled in the art will appreciate that variations may be implemented by those skilled in the art in combination with the prior art and the above-described embodiments, and will not be described herein in detail. Such variations do not affect the essence of the present invention, and are not described herein.
The above description is directed to the preferred embodiment of the present invention. It is to be understood that the invention is not limited to the particular embodiments described above, and that devices and structures not described in detail are understood to be implemented in a manner common in the art; without departing from the scope of the invention, it is intended that the present invention shall not be limited to the above-described embodiments, but that the present invention shall include all the modifications and variations of the embodiments. Therefore, any simple modification, equivalent change and modification made to the above embodiments by the technical entity of the present invention all still fall within the protection scope of the technical solution of the present invention, where the technical entity does not depart from the content of the technical solution of the present invention.
Claims (10)
1. A high-performance silencing structure is characterized by comprising an outer cylinder, a resonance sound absorption layer and an inner cylinder;
openings are formed in the left end and the right end of the outer cylinder, the inner cylinder is coaxially arranged in the outer cylinder, resonance sound absorption layers are arranged on the peripheral inner walls of the outer cylinder, and porous sound absorption material layers are arranged between the inner cylinder and the resonance sound absorption layers;
the inner cylinder body is formed by splicing perforated protective panels, and the resonance sound absorption layer is formed by splicing one, two or three of a perforated plate resonance sound absorption structure, a thin plate resonance sound absorption structure and a single-cavity resonance sound absorption structure.
2. The high performance sound attenuating structure as claimed in claim 1, wherein the outer cylinder is a rectangular cylinder.
3. The high performance sound attenuating structure as claimed in claim 2, wherein the resonant sound absorbing layers on the inner peripheral wall of the rectangular cylinder are the same.
4. The high performance sound-deadening structure according to claim 3, wherein the resonance sound-absorbing layer includes at least one first resonance sound-absorbing unit provided in this order from one end to the other end of the rectangular cylinder, and the first resonance sound-absorbing unit includes a perforated-plate resonance sound-absorbing structure, a thin-plate resonance sound-absorbing structure, a perforated-plate resonance sound-absorbing structure, a single-chamber resonance sound-absorbing structure, and a perforated-plate resonance sound-absorbing structure provided in this order in the axial direction of the rectangular cylinder.
5. The high performance sound attenuation structure according to claim 3, wherein the resonance sound absorbing layer includes a plurality of perforated plate resonance sound absorbing structures arranged in order in the axial direction of the rectangular cylinder.
6. The high performance sound attenuation structure according to claim 3, wherein the resonance sound absorbing layer comprises thin plate resonance sound absorbing structures arranged in order in an axial direction of the rectangular cylinder.
7. The high performance sound attenuation structure according to claim 3, wherein the resonance sound absorbing layer includes a plurality of single-chamber resonance sound absorbing structures arranged in order in the axial direction of the rectangular cylinder.
8. The high performance sound attenuating structure as claimed in claim 2, wherein the resonance sound absorbing layers on the peripheral side walls of the rectangular cylinder are different.
9. The high performance sound damping structure of claim 1, wherein the layer of porous sound absorbing material is fiberglass sound absorbing cotton, polyester sound absorbing cotton, or melamine sound absorbing cotton.
10. The high performance acoustical structure of claim 1 wherein said perforated facing sheet has a perforation rate greater than 20%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021491624.5U CN212276806U (en) | 2020-07-24 | 2020-07-24 | High-performance noise elimination structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021491624.5U CN212276806U (en) | 2020-07-24 | 2020-07-24 | High-performance noise elimination structure |
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| Publication Number | Publication Date |
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| CN212276806U true CN212276806U (en) | 2021-01-01 |
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| CN202021491624.5U Active CN212276806U (en) | 2020-07-24 | 2020-07-24 | High-performance noise elimination structure |
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| CN (1) | CN212276806U (en) |
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2020
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