Auxiliary device for noise test
By designing an auxiliary device for noise testing, utilizing non-parallel sound insulation components and multiple sound absorption structures, the accuracy and safety issues of noise testing in industrial enterprises have been solved, achieving efficient, convenient, and accurate noise measurement.
Patent Information
- Application Number
- CN202422611980.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-28
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-10-28
AI Technical Summary
In industrial enterprises, existing noise testing methods suffer from problems such as significant mutual interference between equipment noise, large measurement deviations, high costs of temporary isolation measures that are not applicable to large equipment, and the inability to isolate equipment in confined spaces, which affect measurement accuracy and safety.
Design an auxiliary device for noise testing, comprising a first sound insulation part, a first sound absorption structure, a second sound insulation part, and a second sound absorption structure arranged sequentially from the outside to the inside. Through the non-parallel arrangement of the sound insulation parts and the multiple sound absorption structures, multiple reflections and absorptions of noise are achieved, thereby reducing noise interference.
It effectively isolates noise from the testing equipment, ensuring measurement accuracy. It has a simple and convenient structure, is easy to operate, does not affect the normal operation of the equipment, and saves time and costs.
Smart Images
Figure CN223539335U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to auxiliary tooling for noise detection, specifically, to an auxiliary device for noise testing. Background Technology
[0002] Industrial enterprises, such as thermal power plants, coal preparation plants, and chemical plants, have a wide variety and large number of equipment, most of which are often clustered together and close to each other, including fans, pumps, compressors, and pipelines. Therefore, industrial enterprises not only have a variety of noise sources and high noise intensity, but also mostly produce continuous steady-state noise.
[0003] As is well known, noise from various equipment in industrial enterprises has several negative impacts. First, it severely affects the physical and mental health of employees and workers. High-noise work environments not only harm the ears, heart, and blood pressure, but also cause irritability, decreased concentration, and ultimately, safety hazards. Second, it seriously affects the acoustic environment of surrounding sensitive areas such as residential areas and villages. Industrial noise is generally characterized by high intensity, wide frequency response, long propagation distance, and a wide range of impact. Furthermore, most industrial equipment operates continuously for 24 hours, thus affecting not only the daytime work and lives of people in the surrounding areas but also their sleep and rest at night. Third, it seriously damages the social image of enterprises. Industrial noise pollution adversely affects the ecological environment of the areas where enterprises are located, hindering the construction of a peaceful, harmonious, and beautiful living environment.
[0004] Whether evaluating the acoustic environment of industrial enterprises or controlling noise pollution, it is necessary to analyze and study the noise characteristics, spectrum, and sound level of each sound source device. The main methods of noise analysis include consulting relevant literature, referencing similar equipment, and on-site measurements. However, due to the lack of relevant noise data for some equipment, consulting literature often fails to meet the requirements. As for the method of referencing similar equipment, differences in production environment, operating conditions, and other factors can lead to significant deviations, thus limiting its applicability, especially for the first set of equipment where there is often no comparable equipment available for reference.
[0005] In practical engineering applications, on-site measurement methods are frequently used. This involves measuring the noise characteristics of the equipment at a certain distance using instruments such as sound level meters when the unit reaches a certain load and is operating normally. Industrial equipment is often arranged close together without barriers, causing noise interference between devices and resulting in significant deviations in noise measurements. To address this, common auxiliary measurement methods include: First, shutting down other equipment to allow the device under test to operate independently, ensuring the direct sound of the device is at least 10 dB(A) greater than the background noise. However, this method can disrupt normal unit operation, even causing shutdowns, and some equipment cannot operate independently, limiting its applicability in practice. Second, temporary isolation measures, such as temporary soundproof barriers or enclosures, are used to physically isolate the device under test from other equipment before noise measurement. However, this method is unsuitable for large equipment, as temporary measures are costly and require dismantling after measurement. Furthermore, for very compactly arranged equipment, limited space makes physical isolation impossible. The installation and removal of isolation measures are also time-consuming and pose safety risks, further limiting the applicability of this method.
[0006] In view of this, there is a need to provide an auxiliary device for noise testing to solve or overcome the above-mentioned technical problems. Utility Model Content
[0007] The technical problem to be solved by this utility model is to provide an auxiliary device for noise testing, which has good sound insulation effect, simple structure and good performance.
[0008] To solve the above-mentioned technical problems, the technical solution proposed by this utility model is as follows:
[0009] An auxiliary device for noise testing includes, from the outside to the inside, a first sound insulation part, a first sound absorption structure, a second sound insulation part, and a second sound absorption structure. The first sound absorption structure fills the space between the first and second sound insulation parts. The second sound absorption structure is disposed on the inner side of the second sound insulation part. An end cap is provided at one end of the first and second sound insulation parts. A handle is provided on the outer end face of the end cap. A through hole is provided in the central area of the end cap, which is suitable for the probe of the testing equipment to pass through.
[0010] Preferably, the second sound insulation part is sleeved inside the first sound insulation part, and the first sound insulation part and the second sound insulation part are not arranged parallel to each other.
[0011] The first sound insulation part is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates; or
[0012] The first sound insulation part is a hollow cylindrical structure.
[0013] Preferably, the second sound insulation part is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates, and the number of sides of the second sound insulation part is equal to the number of sides of the first sound insulation part, and all sides are arranged in parallel; or
[0014] The second sound insulation part is a hollow cylindrical structure, and the central axis of the second sound insulation part coincides with that of the first sound insulation part.
[0015] Preferably, a plurality of reinforcing supports are provided between the first sound insulation part and the second sound insulation part.
[0016] Preferably, the four periphery of the through hole is provided with a first sealing structure.
[0017] Preferably, the other end of the first sound insulation part and the second sound insulation part away from the end sealing plate is provided with a second sealing structure.
[0018] Preferably, both the first sealing structure and the second sealing structure are made of EPDM or chloroprene rubber.
[0019] Preferably, the width or diameter of the end of the first sound insulation part near the end sealing plate is smaller than that of the other end.
[0020] Preferably, the second sound-absorbing structure includes a plurality of pyramidal shells arranged in sequence and a porous sound-absorbing structure disposed within the pyramidal shells, wherein the first sound-absorbing structure is 48K centrifugal glass wool or 120K rock wool, and the porous sound-absorbing structure is 32K centrifugal glass wool.
[0021] Preferably, the surface of the first sound-absorbing structure is bonded with alkali-free hydrophobic glass fiber cloth.
[0022] Through the above technical solution, the auxiliary device for noise testing of this utility model includes, from the outside to the inside, a first sound insulation part, a first sound absorption structure, a second sound insulation part, and a second sound absorption structure. The first sound insulation part and the second sound insulation part are not arranged in parallel. The first sound absorption structure fills the space between the first sound insulation part and the second sound insulation part. The second sound absorption structure is disposed on the inner side of the second sound insulation part. One end of the first sound insulation part and the second sound insulation part is provided with an end sealing plate. A handle is provided on the outer end face of the end sealing plate. A through hole is provided in the central area of the end sealing plate, and the through hole is suitable for the probe of the testing equipment to pass through. In the auxiliary device for noise testing of this utility model, by setting the first sound insulation part and the second sound insulation part in a non-parallel structure, and setting the first sound absorption structure between the first sound insulation part and the second sound insulation part, and setting the second sound absorption structure on the inner side of the second sound insulation part, noise is absorbed and reflected multiple times through the conversion of different media, so that the noise entering the internal space of the auxiliary device for noise testing is almost zero, effectively isolating the influence of noise on the testing equipment. The structure is simple, the operation is convenient, and the use effect is good.
[0023] Other advantages of this utility model and the technical effects of preferred embodiments will be further described in the following detailed description. Attached Figure Description
[0024] Figure 1 This is a three-dimensional structural schematic diagram of a specific embodiment of the auxiliary device for noise testing described in this utility model;
[0025] Figure 2 This is a cross-sectional view of one specific embodiment of the auxiliary device for noise testing described in this utility model;
[0026] Figure 3 This is a second cross-sectional view of a specific embodiment of the auxiliary device for noise testing described in this utility model;
[0027] Figure 4 This is a third cross-sectional view of a specific embodiment of the auxiliary device for noise testing described in this utility model.
[0028] Explanation of reference numerals in the attached figures
[0029] 1 First sound insulation section 2 Second sound insulation section
[0030] 3 First sound-absorbing structure 4 Second sound-absorbing structure
[0031] 401 Multi-faceted pyramidal shell; 402 Porous sound-absorbing structure
[0032] 5. End sealing plate 501 through hole
[0033] 6. Reinforcing bracket; 7. First sealing structure
[0034] 8 Second sealing structure Detailed Implementation
[0035] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.
[0036] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features.
[0038] like Figures 1 to 4 As shown, this utility model provides an auxiliary device for noise testing, which includes, from the outside to the inside, a first sound insulation part 1, a first sound absorption structure 3, a second sound insulation part 2, and a second sound absorption structure 4. The first sound insulation part 1 and the second sound insulation part 2 are not arranged in parallel. The first sound absorption structure 3 fills the space between the first sound insulation part 1 and the second sound insulation part 2. The second sound absorption structure 4 is disposed on the inner side of the second sound insulation part 2. One end of the first sound insulation part 1 and the second sound insulation part 2 is provided with an end sealing plate 5. A handle is provided on the outer end face of the end sealing plate 5. A through hole 501 is provided in the central area of the end sealing plate 5. The through hole 501 is suitable for the probe of the testing equipment to pass through.
[0039] In this invention, the second sound insulation part 2 is fitted inside the first sound insulation part 1, with an end sealing plate 5 at one end. The other end of the first sound insulation part 1 and the second sound insulation part 2 are also sealed with a sealing plate, thus forming a sealed space. The first sound-absorbing structure 3 is disposed within this sealed space and completely fills it. The second sound insulation part 2 is formed as a hollow polygonal hollow cylinder structure or a hollow cylindrical structure; therefore, the second sound-absorbing structure 4 is disposed on the inner surface of the second sound insulation part 2. Preferably, as shown... Figure 3 As shown, the second sound-absorbing structure 4 is arranged in a regular matrix structure.
[0040] Meanwhile, it can be seen that the first sound insulation part 1 and the second sound insulation part 2 are not arranged in parallel, making the longitudinal cross-section of the sealed space a trapezoidal structure. The opening size of the end of the first sound insulation part 1 near the end sealing plate 5 is smaller than the opening size of the other end.
[0041] It should be noted that the materials of the first sound insulation part 1, the first sound absorption structure 3, the second sound insulation part 2, and the second sound absorption structure 4 are all different. This allows external noise to be absorbed in four parts before entering the auxiliary device used for noise testing:
[0042] In the first part, when the sound waves of noise pass through the first sound insulation part 1, due to the sudden change in the characteristic impedance of the interface, the sound waves will be reflected twice on the two surfaces of the first sound insulation part 1. These reflections occur when the sound waves enter the first sound insulation part 1 from the air and when they enter the first sound absorption structure 3 from the first sound insulation part 1. The two reflections greatly reduce the transmission capability of the sound waves.
[0043] In the second part, a portion of the sound waves passing through the first sound insulation section 1 can be absorbed by the first sound absorption structure 3.
[0044] In the third part, when the sound wave passes through the second sound insulation part 2 from the first sound absorption structure 3, due to the sudden change in the interface characteristic impedance, the sound wave will also be reflected twice on the two surfaces of the second sound insulation part 2. These reflections occur when the sound wave enters the second sound insulation part 2 from the first sound absorption structure 3 and when it enters the second sound absorption structure 4 from the second sound insulation part 2. These two reflections further reduce the sound wave transmission capability significantly.
[0045] In the fourth part, the sound waves transmitted from the second sound insulation part 2 are also absorbed and reflected when passing through the second sound absorption structure 4.
[0046] In this way, through multiple reflections and absorptions, the sound waves transmitted from the outside into the auxiliary device are basically eliminated. This allows for the complete elimination of external noise interference with the test results when detecting equipment noise, resulting in more accurate test results.
[0047] It is known that, since the first sound insulation part 1 and the second sound insulation part 2 are not arranged in parallel, some of the sound waves reflected between the first sound insulation part 1 and the second sound insulation part 2 will be reflected multiple times to one end. During the process of multiple reflections to one end, some of the sound waves will gradually dissipate, and there will be no standing wave formed due to multiple reflections in one place because of the parallel arrangement. This can effectively improve the sound insulation.
[0048] In one specific embodiment of this utility model, a handle (not shown in the figure) is provided on the outer end face of the end sealing plate 5. Thus, after the end sealing plate 5 is connected to the second sound insulation part 2, it is convenient for the tester to move or fix the auxiliary device for noise testing of this utility model by means of the handle.
[0049] In a preferred embodiment of the present invention, the second sound insulation part 2 is sleeved inside the first sound insulation part 1, wherein the first sound insulation part 1 is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates; or the first sound insulation part 1 is a hollow frustum structure.
[0050] In one specific embodiment of this utility model, the first sound insulation part 1 is welded together from four trapezoidal galvanized steel plates of equal shape, each galvanized steel plate having a thickness of 1-1.5mm, or it can be formed by bending two steel plates and then welding them together. The cross-section of the first sound insulation part 1 is trapezoidal. After the first sound insulation part 1 is placed on the ground, the angle between each side of it and the horizontal plane is less than 90°.
[0051] In one specific embodiment of this utility model, the first sound insulation part 1 is a hollow frustum structure with a thickness of 1-1.5mm, preferably 1.2mm.
[0052] In a preferred embodiment of the present invention, the second sound insulation part 2 is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates, the number of sides of the second sound insulation part 2 is equal to the number of sides of the first sound insulation part 1 and all sides are arranged in parallel; or the second sound insulation part 2 is a hollow cylindrical structure, and the central axis of the second sound insulation part 2 coincides with that of the first sound insulation part 1.
[0053] In one specific embodiment of this utility model, the second sound insulation part 2 is made of four rectangular aluminum alloy plates of equal shape welded together. The thickness of each aluminum alloy plate is 1-1.5mm, preferably 1.0mm, or it can be made of two aluminum alloy plates bent and then welded together. The cross-section of the first sound insulation part 1 is rectangular. After the first sound insulation part 1 is placed on the ground, each side of it is perpendicular to the horizontal plane.
[0054] In one specific embodiment of this utility model, the first sound insulation part 1 is a hollow cylindrical structure with a thickness of 1-1.5mm.
[0055] In a preferred embodiment of the present invention, a plurality of reinforcing brackets 6 are provided between the first sound insulation part 1 and the second sound insulation part 2.
[0056] In one specific embodiment of this utility model, the reinforcing bracket 6 is a U-shaped channel steel, I-beam steel, or steel plate structure. According to structural strength requirements, the reinforcing bracket 6 is respectively installed at both ends and the center of the first sound insulation part 1 and the second sound insulation part 2. Of course, the number of reinforcing brackets 6 can be increased or decreased according to actual usage requirements.
[0057] In addition, the reinforcing bracket 6 can be connected to the first sound insulation part 1 and the second sound insulation part 2 by riveting or welding.
[0058] More preferably, the reinforcing bracket 6 is a U-shaped bracket structure, with the openings of the reinforcing bracket 6 at both ends facing each other, and the bottom plane of the reinforcing bracket 6 is flush with the end faces of the first sound insulation part 1 and the second sound insulation part 2.
[0059] In a preferred embodiment of the present invention, the four periphery of the through hole 501 is provided with a first sealing structure 7, and the other end of the first sound insulation part 1 and the second sound insulation part 2 away from the end sealing plate 5 is provided with a second sealing structure 8.
[0060] In a preferred embodiment of this utility model, both the first sealing structure 7 and the second sealing structure 8 are EPDM or chloroprene rubber.
[0061] Specifically, the first sealing structure 7 is made of EPDM or neoprene rubber with a thickness of 3mm, and the second sealing structure 8 is made of EPDM or neoprene rubber with a thickness of 8mm.
[0062] In one specific embodiment of this utility model, the first sealing structure 7 is made of EPDM or neoprene rubber sheet with a thickness of 3mm. The first sealing structure 7 circumferentially wraps around the edge of the through hole 501 and is bonded and fixed with adhesive. After bonding and fixing, the cross-sectional shape of the first sealing structure 7 is annular.
[0063] In one specific embodiment of this utility model, the second sealing structure 8 is bonded to the reinforcing bracket 6 located at the end, and its cross-section is serrated.
[0064] In a preferred embodiment of the present invention, the width or diameter of the end of the first sound insulation part 1 near the end sealing plate 5 is smaller than that of the other end.
[0065] In other words, the first sound insulation part 1 has a smaller opening at one end and a larger opening at the other end, forming a trumpet shape, and the end sealing plate 5 is located at the end of the first sound insulation part 1 with the smaller opening.
[0066] In a preferred embodiment of the present invention, the second sound-absorbing structure 4 includes a plurality of pyramidal shells 401 arranged in sequence and a porous sound-absorbing structure 402 disposed within the pyramidal shells 401. The first sound-absorbing structure 3 is 48K centrifugal glass wool or 120K rock wool, and the porous sound-absorbing structure 402 is 32K centrifugal glass wool.
[0067] In one specific embodiment of this utility model, the first sound-absorbing structure 3 has a tiny gap and continuous holes. Sound waves propagate in the tiny gap and continuous holes of the first sound-absorbing structure 3, causing the air inside the gap and holes to vibrate and rub against the sidewalls of the gap and the walls of the holes. Due to the effects of friction and viscous dissipation, some of the sound energy is converted into heat energy, further reducing the energy of the sound waves.
[0068] In a preferred embodiment of the present invention, the surface of the first sound-absorbing structure 3 is bonded with alkali-free water-repellent glass fiber cloth.
[0069] As a preferred embodiment of the auxiliary device for noise testing of this utility model, it includes a first sound insulation part 1, a second sound insulation part 2 sleeved within the first sound insulation part 1, a first sound-absorbing structure 3 disposed between the first sound insulation part 1 and the second sound insulation part 2, and a second sound-absorbing structure 4 disposed on the inner surface of the second sound insulation part 2. The first sound insulation part 1 is made of galvanized steel plate with a thickness of 1.2 mm, and the second sound insulation part 2 is made of aluminum alloy plate with a thickness of 1.0 mm. One end of the first sound insulation part 1 and the second sound insulation part 2 is provided with an end sealing plate 5, and a handle is provided on the outer end face of the end sealing plate 5. A through hole 501 is provided in the central area of the end sealing plate 5, and a first sealing structure 7 is provided around the four periphery of the through hole 501. The other end of the first sound insulation part 1 and the second sound insulation part 2 away from the end sealing plate 5 is provided with a second sealing structure 8, which is bonded to a reinforcing bracket 6 located at the end, and its cross-section is serrated. Both the first sealing structure 7 and the second sealing structure 8 are made of EPDM or neoprene rubber. Multiple reinforcing supports 6 are provided between the first sound insulation part 1 and the second sound insulation part 2. The reinforcing supports 6 are U-shaped supports, and the openings of the reinforcing supports 6 at both ends are arranged opposite each other. The second sound-absorbing structure 4 includes multiple polygonal pyramidal shells 401 arranged in sequence and porous sound-absorbing structures 402 disposed within the polygonal pyramidal shells 401. The polygonal pyramidal shells 401 are square pyramidal structures. The first sound insulation part 1 is a hollow square truncated pyramidal structure with a trapezoidal cross-section, and the second sound insulation part 2 is a hollow square prism structure with a rectangular cross-section. The first sound-absorbing structure 3 is made of 48K centrifugal glass wool or 120K rock wool, and the porous sound-absorbing structure 402 is made of 32K centrifugal glass wool. The surface of the first sound-absorbing structure 3 is bonded with alkali-free water-repellent glass fiber cloth.
[0070] Based on the above-described preferred embodiment, it can be seen that the noise absorption process of the auxiliary device for noise testing of this utility model is as follows:
[0071] The probe of the testing equipment passes through the first sealing structure 7 and extends into the auxiliary device, with one end of the auxiliary device equipped with the second sealing structure 8 resting against the equipment being tested. Sound waves from other equipment first pass through the first sound insulation part 1, resulting in two reflections on its two surfaces, significantly reducing sound wave transmission. Sound waves passing through the first sound insulation part 1 propagate within the tiny gaps and pores of the centrifugal glass wool or rock wool in the first sound-absorbing structure 3, causing air vibration and friction between the sound waves and the pore walls. Due to friction and viscous dissipation, some sound energy is converted into heat energy, achieving the purpose of reducing sound wave energy. Sound waves propagating to the second sound insulation part 2 also undergo two reflections on its two surfaces, further significantly reducing sound wave transmission. Sound waves transmitted from the second sound insulation part 2 enter the second sound-absorbing structure 4. The porous sound-absorbing structure 402 reduces noise through friction between the sound waves and the pore walls, while the pyramidal shell 401 reflects the noise-reduced sound waves. Therefore, through layer-by-layer reflection and friction dissipation, the noise entering the auxiliary device is almost zero, thereby minimizing the impact of noise from surrounding equipment on the detection equipment.
[0072] In summary, this utility model can achieve the following seven important effects:
[0073] First, the auxiliary device for noise testing of this utility model is suitable for measuring equipment noise in complex acoustic environments in industrial enterprises, avoiding the influence of noise from other equipment on the noise measurement of the equipment under test.
[0074] Secondly, the auxiliary device for noise testing of this utility model does not require repeated installation and disassembly. It can form a sealed and soundproof measurement space by being closely attached to the surface of the equipment being tested, which can save a lot of time and cost.
[0075] Third, the auxiliary device for noise testing of this utility model has a simple structure, small size, and relatively light weight. It can be used by two people working together to complete the measurement work. It is convenient to use and easy to carry.
[0076] Fourth, the auxiliary device for noise testing of this utility model will not affect the normal operation of the target equipment during use, thus ensuring the continuity of production.
[0077] Fifth, in the auxiliary device for noise testing of this utility model, the thickness and material of the first sound insulation part 1 and the second sound insulation part 2 are different, so that their critical frequencies are staggered to eliminate or reduce the influence of the coincidence effect on the sound insulation.
[0078] Sixth, in the auxiliary device for noise testing of this utility model, the outer end face of the second sealing structure 8 is formed in a sawtooth shape, which can not only prevent sound leakage through gaps, but also greatly reduce the impact of equipment vibration transmission. The cross-sectional shape of the first sealing structure 7 is annular, which ensures the sealing performance of this utility model while meeting the microphone measurement requirements and preventing sound leakage through gaps.
[0079] Seventh, in the auxiliary device for noise testing of this utility model, the first sound insulation part 1 and the second sound insulation part 2 are not arranged in parallel, which can prevent the sound wave from forming a standing wave between the two and improve the sound insulation.
[0080] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.
[0081] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this utility model will not describe the various possible combinations separately.
[0082] Furthermore, various different embodiments of this utility model can be combined in any way, as long as they do not violate the spirit of this utility model, they should also be regarded as the content disclosed by this utility model.
Claims
1. An auxiliary device for noise testing, characterized in that, From the outside to the inside, it includes a first sound insulation part (1), a first sound absorption structure (3), a second sound insulation part (2), and a second sound absorption structure (4). The first sound absorption structure (3) fills the space between the first sound insulation part (1) and the second sound insulation part (2). The second sound absorption structure (4) is disposed on the inner side of the second sound insulation part (2). One end of the first sound insulation part (1) and the second sound insulation part (2) is provided with an end sealing plate (5). The outer end face of the end sealing plate (5) is provided with a handle. The central area of the end sealing plate (5) is provided with a through hole (501). The through hole (501) is suitable for the probe of the detection device to pass through.
2. The auxiliary device for noise testing according to claim 1, characterized in that, The first sound insulation part (1) and the second sound insulation part (2) are not arranged in parallel, and the second sound insulation part (2) is sleeved inside the first sound insulation part (1). The first sound insulation part (1) is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates; or The first sound insulation part (1) is a hollow cylindrical structure.
3. The auxiliary device for noise testing according to claim 2, characterized in that, The second sound insulation part (2) is a polygonal hollow frustum structure formed by bending and enclosing multiple steel plates. The number of sides of the second sound insulation part (2) is equal to the number of sides of the first sound insulation part (1), and all sides are arranged in parallel; or The second sound insulation part (2) is a hollow cylindrical structure, and the central axis of the second sound insulation part (2) coincides with that of the first sound insulation part (1).
4. The auxiliary device for noise testing according to claim 3, characterized in that, Multiple reinforcing brackets (6) are also provided between the first sound insulation part (1) and the second sound insulation part (2).
5. The auxiliary device for noise testing according to claim 1, characterized in that, The four periphery of the through hole (501) is provided with a first sealing structure (7).
6. The auxiliary device for noise testing according to claim 5, characterized in that, The other end of the first sound insulation part (1) and the second sound insulation part (2) away from the end sealing plate (5) is provided with a second sealing structure (8).
7. The auxiliary device for noise testing according to claim 6, characterized in that, Both the first sealing structure (7) and the second sealing structure (8) are EPDM or chloroprene rubber.
8. The auxiliary device for noise testing according to any one of claims 1 to 7, characterized in that, The width or diameter of the end of the first sound insulation part (1) near the end sealing plate (5) is smaller than that of the other end.
9. The auxiliary device for noise testing according to any one of claims 1 to 7, characterized in that, The second sound-absorbing structure (4) includes a plurality of pyramidal shells (401) arranged in sequence and a porous sound-absorbing structure (402) disposed in the pyramidal shells (401). The first sound-absorbing structure (3) is 48K centrifugal glass wool or 120K rock wool, and the porous sound-absorbing structure (402) is 32K centrifugal glass wool.
10. The auxiliary device for noise testing according to any one of claims 1 to 7, characterized in that, The surface of the first sound-absorbing structure (3) is bonded with alkali-free water-repellent glass fiber cloth.