CN214164887U - Noise-reduction interior trim system for special vehicle cab - Google Patents
Noise-reduction interior trim system for special vehicle cab Download PDFInfo
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- CN214164887U CN214164887U CN202022797040.7U CN202022797040U CN214164887U CN 214164887 U CN214164887 U CN 214164887U CN 202022797040 U CN202022797040 U CN 202022797040U CN 214164887 U CN214164887 U CN 214164887U
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Abstract
The utility model relates to a noise reduction interior trim system for a special vehicle cab, which comprises any one or a combination of a sound absorption structure interior trim, a high-strength multilayer composite floor structure and a sound absorption and insulation structure of an engine cabin; the roof sound absorption structure sequentially comprises a first sound absorption material and a first protective surface layer from inside to outside, and the first sound absorption material is attached to the roof; the high-strength multilayer composite floor structure sequentially comprises floor leather, a damping composite interlayer structure and a second sound absorption material from top to bottom, and the second sound absorption material is arranged by being attached to the ground; the engine compartment sound absorption and insulation structure sequentially comprises a third sound absorption material, a damping steel plate, a fourth sound absorption material and a second protective surface layer from inside to outside, wherein the third sound absorption material is attached to the inner side of the compartment plate, and the fourth sound absorption material is attached to the outer side of the compartment plate. Compared with the prior art, the utility model discloses it is wide, application scope wide to fall the frequency range of making an uproar.
Description
Technical Field
The utility model belongs to the technical field of vehicle noise control technique and specifically relates to an interior plaque system of making an uproar falls for special type vehicle driver's cabin is related to.
Background
At present, most special vehicle cabs have the problem of different degrees of poor noise environments, abnormal sound occurs under a certain vehicle speed, or the average value of noise is too large under most working conditions, so that the condition is caused by various reasons. For special vehicles, the engine power is high, and is mostly exposed outside and close to the cab, so that the noise directly transmitted to the cab through air is excessive; the axles and the suspensions are numerous, and the problem of the mode matching of the whole vehicle is not considered deeply and meticulously; the cab system is unreasonable in design, the structural mode and the sound cavity mode are easy to resonate and generate rolling, and in addition, the use of sound absorption and sound insulation materials is inexperienced.
From the characteristic analysis of a noise source, the special vehicle is used as a complex electromechanical system, the axles are numerous, the vibration transmission path is complex, and the main factors influencing the noise in the cab are variable. When the vehicle runs at a low speed, a power system and a transmission system are main vibration sources and noise sources of a cab, and are mostly concentrated in 200Hz and belong to low-frequency noise in terms of frequency band distribution; along with the increase of the vehicle speed, tire noise caused by road excitation, transmission noise of a speed change differential and brake noise are prominent, the range of 200-1000 Hz is taken as the main factor, and the noise belongs to intermediate frequency noise; during high-speed running, the wind-to-noise ratio is increased, and the wind-to-noise ratio becomes a main noise source in a cab, is concentrated in the range of 1000-5000 Hz and belongs to high-frequency noise.
In terms of research progress, Noise, Vibration and Harshness (NVH) have become popular areas for research in the automobile industry in recent years, so that not only passenger car companies are engaged in research and development of NVH performance, but also commercial car NVH performance is gaining more and more attention from various automobile enterprises. The noise and vibration requirements of governments and enterprises in various countries for special off-road vehicles are also becoming more and more stringent. Most of the research objects in the noise field in China are passenger vehicles, the research on the NVH performance of special vehicles is less, and the requirements on the distance between the vibration and the noise level of related vehicles in China have certain gaps, so that the research objects become a limiting factor for restricting the development of the body structure of the special vehicles. And in a noise environment, passengers are stressed, easy to fatigue, irritated in mood and inattentive, and are more likely to cause adverse reactions such as dizziness, distraction, nausea and the like and even cardiovascular and cerebrovascular diseases when being in the noise environment for a long time. The special off-road vehicle mostly runs on the terrain with poor road conditions or no road, the possible types of the encountered excitation are many, the vibration and the noise in the cab are serious, and the influence of the noise in the special vehicle on soldiers in battle is fatal. Therefore, the research on NVH related technologies of the special vehicle cab has very important significance in the aspects of economic value and national benefits.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing an interior trim system of making an uproar falls for overcoming the defect that above-mentioned prior art exists for special type vehicle driver's cabin.
The purpose of the utility model can be realized through the following technical scheme:
a noise reduction interior decoration system for a special vehicle cab comprises any one or combination of more than one of sound absorption structure interior decoration, a high-strength multilayer composite floor and engine compartment sound absorption and insulation structure interior decoration;
the sound absorption structure interior decoration comprises a first sound absorption material and a first protective surface layer from inside to outside in sequence, and the first sound absorption material is arranged by being attached to the wall surface of the cab;
the high-strength multilayer composite floor sequentially comprises floor leather, a composite sandwich floor, a constraint damping plate and a second sound absorption material from top to bottom, wherein the second sound absorption material is arranged by being attached to the ground;
the interior decoration of the sound absorption and insulation structure of the engine compartment sequentially comprises a third sound absorption material, a damping steel plate, a fourth sound absorption material and a second protective surface layer from inside to outside, and the third sound absorption material is attached to the compartment plate.
Preferably, the first protective layer is made of a light perforated metal plate or a composite plate.
Preferably, the diameter of the through hole on the first protective layer is 2-3 mm.
Preferably, the perforation rate on the first protective layer is 20-30%.
Preferably, the first sound absorbing material comprises a porous sound absorbing material or a resonant sound absorber.
Preferably, the splicing position of the high-strength multilayer composite floor is sealed by a sealing strip or spliced by a tongue-and-groove.
Preferably, the bending strength of the high-strength multilayer composite floor is more than or equal to 100MPa, the bending modulus is more than or equal to 40MPz, and the weighted sound insulation quantity is more than 35 dB.
Preferably, the flooring in the high-strength multi-layered composite flooring structure comprises rubber flooring.
Preferably, the second sound-absorbing material comprises a porous sound-absorbing material or a resonant sound-absorbing body.
Preferably, the third sound-absorbing material and the fourth sound-absorbing material comprise porous sound-absorbing materials or resonant sound-absorbing materials.
Compared with the prior art, the utility model has the advantages of as follows:
(1) the utility model provides an interior trim system that the special type vehicle driver's cabin of making an uproar falls that falls high, the reliability is high, convenient maintenance, low cost, the defect that exists among the prior art can effectively be overcome to the interior trim system that provides, simple structure, and more current interior trim can widen the frequency band of making an uproar that falls, and the installation, dismantlement are convenient, and adaptability is strong, and the reliability is high.
(2) The utility model discloses be not enough seriously and floor thickness restriction scheduling problem to vibration corridor floor sound insulation volume, in the multilayer laminate flooring design that excels in, adopt sound absorbing material to carry out the sound absorption, the high sound insulation volume structure of "laminate flooring + restraint damping panel" has been adopted simultaneously, can effectively restrain the noise that sees through floor infiltration driver's cabin, it can know through numerical simulation calculation, this structure can reach 28.9dB at the average sound insulation volume of 50 ~ 3150Hz frequency range, in addition, it is unusual big to consider transfer case and automobile body connected position vibration, so restraint damping panel has been adopted in the floor structure, in order to restrain the production of its low frequency secondary structure noise.
(3) The utility model discloses to car inner surface layer seal noise car internal acoustic noise reduction performance is great, consequently, in the scheme design, has adopted the sound-absorbing structure interior trim, has adopted the acoustics metamaterial of heat resistance in the engine compartment, and two kinds of above materials can reach 0.5 at 300 ~ 1500Hz average sound absorption, fall through the sound absorption and make an uproar, can make the engine compartment internal noise reduce 3dB, reduce 2dB in the driver's cabin.
Drawings
Fig. 1 is a schematic structural view of an interior decoration of a sound absorption and insulation structure of an engine compartment of the present invention;
fig. 2 is a schematic structural view of the sound absorption structure interior of the present invention;
FIG. 3 is a schematic structural view of the high-strength multi-layer composite floor of the present invention;
FIG. 4 is an enlarged view of portion A of FIG. 3;
FIG. 5 is a plot of sound absorption coefficient for a 50mm thick melamine acoustic foam;
in the figure, (1) is a nail; (2) is a perforated structural plate; (3) is melamine sound absorbing foam; (4) is a power compartment clapboard; (5) is a damping sound insulation plate; (6) is a constraint steel plate; (7) is an acoustic metamaterial; (8) is a detachable fixing screw; (9) an aluminum alloy pressing strip; (10) the inner square tube is fixed with the top; (11) is a rivet connection; (12) is an L-shaped bent edge; (13) fixing the touch nails; (14) is a vehicle body frame; (15) m6 flat-head self-tapping screw and gasket; (16) is melamine sound absorbing foam; (17) is a micro-perforated acoustic panel; (18) splicing the tongue-and-groove of the plate; (19) fixing screws for the floor; (20) is a constraint steel plate; (21) is a damping sound-proof board; (22) is a vehicle body framework; (23) is a foamed aluminum sandwich floor; (24) is made of polyimide sound-absorbing and heat-insulating cotton and high-density fireproof cloth; (25) splicing the tongue-and-groove of the floor board; (26) fixing screws for the floor; (27) is floor leather; (28) is a constraint steel plate; (29) is a damping sound-proof board; (30) is a foamed aluminum sandwich floor; (31) is polyimide foam; (32) is a vehicle body framework.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Note that the following description of the embodiments is merely an example of the nature, and the present invention is not intended to limit the application or the use thereof, and the present invention is not limited to the following embodiments.
Examples
A noise reduction interior decoration system for a special vehicle cab comprises any one or combination of more than one of sound absorption structure interior decoration, a high-strength multilayer composite floor and engine compartment sound absorption and insulation structure interior decoration;
the sound absorption structure interior sequentially comprises a first sound absorption material and a first protective layer from inside to outside, and the first sound absorption material is attached to the wall surface of the cab;
the high-strength multilayer composite floor sequentially comprises floor leather, a damping composite sandwich floor and a second sound absorption material from top to bottom, wherein the second sound absorption material is arranged by being attached to the ground;
the interior decoration of the sound absorption and insulation structure of the engine compartment sequentially comprises a third sound absorption material, a damping steel plate, a fourth sound absorption material and a second protective surface layer from inside to outside, and the third sound absorption material is attached to the compartment plate.
The first protective layer is made of a light perforated metal plate or a composite plate.
The diameter of the through hole on the first protective layer is 2-3 mm.
The perforation rate on the first protective layer is 20-30%.
The first sound absorbing material comprises a porous sound absorbing material or a resonant sound absorber.
The splicing position of the high-strength multilayer composite floor is sealed by a sealing strip or spliced by a tongue-and-groove.
The bending strength of the high-strength multilayer composite floor is more than or equal to 100MPa, the bending modulus is more than or equal to 40MPz, and the weighting sound insulation quantity is more than 35 dB.
The flooring in the high-strength multi-layer composite flooring structure comprises rubber flooring.
The second sound absorbing material includes a porous sound absorbing material or a resonant sound absorber.
The third sound absorbing material and the fourth sound absorbing material comprise porous sound absorbing materials or resonance sound absorbers.
Wherein, porous sound absorbing material inhales the sound foam like the melamine, can also be glass wool, mineral wool, rock wool and fiber material, and the resonance sound absorber is if adopting cavity resonance sound absorbing structure, and resonance sound absorbing structure's sound absorption principle is: when the frequency of the sound wave is consistent with the natural vibration frequency of the resonance sound absorption structure, resonance occurs, the sound wave excites the resonance sound absorption structure to generate vibration, and the amplitude is maximized, so that the sound energy is consumed, and the purpose of sound absorption is achieved.
Specifically, the method comprises the following steps:
1. sound absorption structure interior trim
The sound absorption structure interior trim is mainly used for positions such as the outer surface of a power cabin, a vehicle roof and the like, and adopts different sound absorption measures according to different noise source characteristics and functional requirements. The scheme of the part mainly aims at improving the sound absorption coefficient of the material so as to reduce the indoor reverberation noise and improve the working sound environment of personnel, and the specific implementation scheme is as follows:
the first sound absorbing material of sound absorbing structure interior trim adopts melamine to inhale the sound foam, and first armour layer adopts the perforated plate, perforation diameter (about 2 ~ 3mm), perforation rate (20 ~ 30%), through optimizing behind perforation diameter and the perforation rate, can realize high sound absorption performance to the specific frequency channel, arranges the scheme and see figure 2. The interior decoration of the sound absorption structure has the following performance characteristics:
1) high sound absorption coefficient
The melamine sound absorption foam has the advantages that the interior of the open pore is filled with fine gaps and a semi-open pore structure, so that a large amount of incident sound wave energy can be absorbed, the sound waves are attenuated, through tests, the sound absorption coefficient of the melamine foam with the thickness of 30mm in the middle and high frequency range of 1000-2000 Hz has an obvious noise peak value, is close to 1.0 and is far higher than that of other sound absorption materials, and is shown in figure 5.
2) The construction is simple and quick, and the veneer can be repeatedly disassembled and assembled
In the construction process, the melamine foam is provided with the pressure-sensitive adhesive, can be directly cut according to the size of a construction object, then the release paper is torn, and the melamine foam can be directly bonded or can be reinforced in an auxiliary mode of nail collision bonding. In addition, the larger edge gap needs to be coated with sealant. The size of the perforated plate of the first protective layer can be customized according to the size on site or prefabricated in advance, and the cutting on site is convenient. The panel floats on the sound-absorbing foam, the splicing opening is fixed by an aluminum pressing strip, and the aluminum pressing strip is fixed on the bulkhead through a detachable nut and can be detached repeatedly.
3) Environment-friendly sound-absorbing material made of material
The melamine foam does not contain fine fiber emission, does not have glass fiber pulverization or flying in the cutting and construction processes, does not contain halogen or heavy metal flame retardant, has unique chemical stability due to a stable chemical structure and a crosslinking system, and completely meets the national green and environment-friendly standards in the fields of indoor decoration, daily necessities, noise reduction of vehicles and the like.
4) The sound-absorbing material is flame-retardant, fireproof, heat-insulating and high-temperature-resistant
The melamine foam can reach the flame retardant grade of B1 without adding any flame retardant, and a compact coke layer is formed on the surface of a combustion body after the melamine foam contacts open fire so as to retard combustion, and the melamine foam has the advantages of no dripping, no toxic smoke, no combustion and self-extinguishing after being away from fire. The material is suitable for working at the working condition of 200-240 ℃ for a long time, and does not have decomposition and deformation phenomena below 530 ℃.
2. High-strength multi-layer composite floor
The floor is one of main transmission channels of vibration and noise, is the position that needs the key protection to handle, and floor major structure adopts from top to bottom: leather, a composite sandwich floor, a constraint damping plate and a second sound absorption material, which are shown in figures 3 and 4. Wherein every part of floor part can all leave the factory and customize, and the whole preparation is installed as a module scene, also can divide into three parts and install respectively, and the flexibility is higher. This solution has the following advantages:
1) high damping multilayer composite structure, the sound insulation performance is excellent:
the composite sandwich floor adopts closed-cell foamed polyurethane material, and the transmission of medium-high frequency sound waves can be effectively isolated by the closed gap. In order to avoid the occurrence of sound coincidence effect (sound leakage phenomenon) caused by modal resonance of the whole structure, the surface is pasted with a high-damping vibration attenuation material, so that the whole damping loss and sound insulation capability can be improved, and the vibration energy caused by sound waves is effectively converted into heat energy to be dissipated. Meanwhile, the multilayer interface can effectively increase the repeated reflection and refraction of sound waves, increase the sound transmission distance and enhance the sound insulation performance.
2) The construction is high in efficiency, convenient and flexible in operation:
the operation method and the process of the light floor are basically consistent with the operation mode of wood, and the conventional electric tool can be used for cutting, drilling, trimming and the like. The size of the plate can be cut on site and can also be customized after leaving factory. The lap joint of panel reservation is opened mouthful, and the concatenation is convenient quick, can prevent again that the sound leakage from. After the damping plate is cut, the damping plate is directly glued and bonded on the composite sandwich floor, and the whole construction is rapid and the construction efficiency is high.
3. Sound absorption and insulation structure of engine compartment
The engine compartment partition is one of main transmission channels of vibration and noise, is a part needing to be mainly subjected to protection treatment, and adopts the following scheme: including third sound absorbing material, damping steel sheet, fourth sound absorbing material, second armor, as shown in figure 1, this scheme main advantage, as follows:
1) the baffle increases the damping steel sheet, effectively avoids the sound wave to arouse that panel resonance leads to the emergence of identical effect (sound leakage) phenomenon:
because the noise in the engine compartment is extremely high, and the compartment plate is a thin-wall steel component, the damping loss of the compartment plate is very low, the structural resonance phenomenon is easily caused under the excitation of sound waves, the secondary structural noise of the compartment plate is excited, and the compartment plate loses the sound insulation capability in the resonance frequency band. Therefore, the high-performance constraint damping plate structure is laid on the surface, vibration energy can be efficiently converted into heat energy to be dissipated, the structural noise radiation of the partition plate is reduced, and in addition, the damping plate and the constraint steel plate play a role in increasing the sound insulation energy.
2) The sound absorption metamaterial is hung, medium and low frequency noise is efficiently absorbed, and noise transmission is suppressed at the source:
because the internal noise of the engine is extremely high, and the noise also has a relatively obvious response peak value in a medium-low frequency band, the problem of medium-low frequency noise is difficult to solve by a common sound absorption member under the limited thickness, therefore, an acoustic metamaterial is hung towards one side of the engine, and the low-frequency resonance sound absorption is realized by utilizing the special structural structure of the metamaterial, so that the direct radiation air noise of the engine is reduced, the noise energy is attenuated from the source, and the noise transmission to the periphery is inhibited. The acoustics metamaterial is current material, the utility model discloses do not claim protection material itself.
3) The construction is efficient and quick:
the structural size of the constrained damping plate can be randomly prefabricated and formed in advance or cut on site, and the constrained damping plate is formed by brushing glue on site and bonding. The super material of acoustics self structural strength is high, can assist the welding a small amount of supporting screw prevent transversely collapse can, vertical direction can rely on self structural strength to support.
The above embodiments are merely examples and do not limit the scope of the present invention. These embodiments may be implemented in other various manners, and various omissions, substitutions, and changes may be made without departing from the technical spirit of the present invention.
Claims (10)
1. A noise reduction interior trim system for a special vehicle cab is characterized by comprising any one or combination of more of sound absorption structure interior trim, a high-strength multilayer composite floor and engine compartment sound absorption and insulation structure interior trim;
the sound absorption structure interior decoration comprises a first sound absorption material and a first protective surface layer from inside to outside in sequence, and the first sound absorption material is arranged by being attached to the wall surface of the cab;
the high-strength multilayer composite floor sequentially comprises floor leather, a composite sandwich floor, a constraint damping plate and a second sound absorption material from top to bottom, wherein the second sound absorption material is arranged by being attached to the ground;
the interior decoration of the sound absorption and insulation structure of the engine compartment sequentially comprises a third sound absorption material, a damping steel plate, a fourth sound absorption material and a second protective surface layer from inside to outside, and the third sound absorption material is attached to the compartment plate.
2. The noise reduction interior trim system for a special vehicle cab according to claim 1, wherein the first facing layer is a lightweight perforated metal sheet or a composite sheet.
3. The noise reduction interior trim system for the cab of the special vehicle as claimed in claim 2, wherein the diameter of the through hole in the first protective layer is 2-3 mm.
4. The noise reduction interior trim system for the cab of the special vehicle as claimed in claim 2 or 3, wherein the first protective layer has a perforation rate of 20-30%.
5. A noise reducing interior trim system for a special vehicle cab as claimed in claim 1 wherein the first sound absorbing material comprises a porous sound absorbing material or a resonant sound absorber.
6. The noise reduction interior trim system for the special vehicle cab according to claim 1, wherein the splicing position of the high-strength multilayer composite floor is sealed by a sealing strip or spliced by a tongue and groove.
7. The noise reduction interior decoration system for the special vehicle cab is characterized in that the bending strength of the high-strength multilayer composite floor is larger than or equal to 100MPa, the bending modulus of the high-strength multilayer composite floor is larger than or equal to 40MPz, and the weighted sound insulation quantity is larger than 35 dB.
8. The noise reducing interior trim system for a special vehicle cab of claim 1, wherein the flooring in the high strength multi-layer composite floor structure comprises rubber flooring.
9. The noise reducing interior trim system for a special vehicle cab of claim 1, wherein the second sound absorbing material comprises a porous sound absorbing material or a resonant sound absorbing material.
10. The noise reducing interior trim system for a special vehicle cab of claim 1, wherein the third and fourth sound absorbers comprise porous sound absorbers or resonant sound absorbers.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114184683A (en) * | 2021-10-18 | 2022-03-15 | 中国电器科学研究院股份有限公司 | Sound insulation and heat preservation heat insulation box body and walk-in high-low temperature silencing box |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114184683A (en) * | 2021-10-18 | 2022-03-15 | 中国电器科学研究院股份有限公司 | Sound insulation and heat preservation heat insulation box body and walk-in high-low temperature silencing box |
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