Air filter and vehicle

Abstract

The present invention relates to an air filter and a vehicle, comprising: an air filter body, with an air intake duct formed inside; a multi-stage muffler structure, installed on the air filter body, and having a plurality of mutually connected muffler chambers, wherein at least one of the muffler chambers is connected to the air intake duct; a first muffler pipe, installed on the multi-stage muffler structure, one end of the first muffler pipe is located outside the multi-stage muffler structure, and the other end passes through a plurality of muffler chambers in sequence, and the portion of the first muffler pipe located in each muffler chamber has a first muffler hole, and the noise wave in the first muffler pipe enters each muffler chamber through the first muffler hole. Through the above-mentioned air filter, the noise entering the air filter can be effectively attenuated, the sound quality in the cab can be improved, and the driving comfort of the user in the car cab can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to an air filter and a vehicle. Background Art

[0002] At present, commercial vehicle users have gradually increased their requirements for the comfort of the cab, and users are paying more and more attention to the sound quality inside the car. The noise wave at the pipe mouth of the commercial vehicle intake system is an important aspect that affects the noise inside the car. The noise wave at the pipe mouth of the intake system mainly comes from the noise waves generated and coupled with each other during the operation of the engine combustion, the supercharger and the air compressor and transmitted to the pipe mouth of the intake system. Among them, China has conducted relevant research and formulated measures on the noise waves transmitted to the intake system by engine combustion and supercharger operation, but there is a lack of relevant noise wave research and mature improvement measures for air compressors. In addition, with the improvement of air compressor performance, the impact on the noise wave at the pipe mouth of the intake system is gradually increasing.

[0003] At present, domestic and foreign fuel and gas commercial vehicles are generally equipped with air compressors, which mainly provide compressed air for the power source of the braking system. The clean air filtered by the air filter in the intake system enters the cylinder of the air compressor through the connecting pipe intake pipe of the air compressor air inlet and the intake system interface, and is diverted in the cylinder so that part of the air enters the piston of the air compressor, and then is compressed by the piston to form compressed air; and in the process of air compressor compressing air, noise waves will inevitably be generated, and the noise waves generated by the air compressor will be transmitted to the intake system through the intake pipe of the air compressor and the intake system, and coupled with the noise waves generated by engine combustion and supercharger and transmitted to the intake port of the intake system, and finally through the rear panel of the cab to form a sound cavity resonance in the cab, affecting the sound quality in the cab, and finally enter the car cab through the engine intake system in the intake system of the car engine, affecting the user's driving experience. Summary of the invention

[0004] Based on the above background, it is necessary to provide an air filter and vehicle to improve the above defects in order to address the problem that the noise waves generated by the air compressor compressing the air are coupled with the noise waves generated by the engine combustion and the supercharger and affect the sound quality in the car cabin through the intake system inlet.

[0005] An air filter, comprising:

[0006] The air filter body has an air intake duct formed inside;

[0007] A multi-stage muffler structure, mounted on the air filter body, and having a plurality of mutually connected muffler chambers, wherein at least one of the muffler chambers is connected to the air intake duct;

[0008] A first silencer pipe is installed on the multi-stage silencer structure, one end of the first silencer pipe is located outside the multi-stage silencer structure, and the other end passes through the plurality of silencer cavities in sequence, and the portion of the first silencer pipe located in each of the silencer cavities has a first silencer hole, and the noise wave in the first silencer pipe enters each of the silencer cavities through the first silencer hole.

[0009] In one embodiment, the air filter also includes a second silencer, one end of which is located in the intake duct, and the other end is located in one of the silencer chambers, and the portion of the second silencer located in each of the silencer chambers has a second silencer hole, so that the noise waves in the second silencer enter the silencer chamber through the second silencer hole.

[0010] In one embodiment, the first muffler pipe is located at one end in the muffler cavity, and is located in the same muffler cavity as the second muffler pipe is located at one end in the muffler cavity.

[0011] In one embodiment, the muffler chamber includes three muffler chambers, namely a first muffler chamber, a second muffler chamber and a third muffler chamber;

[0012] The end of the first muffler pipe passes through the first muffler chamber and the second muffler chamber in sequence and is finally located in the third muffler chamber, and one end of the second muffler pipe is located in the third muffler chamber.

[0013] In one embodiment, the portion of the first sound-absorbing pipe located in each of the sound-absorbing chambers has a plurality of the first sound-absorbing holes, and the number of the first sound-absorbing holes in each of the sound-absorbing chambers is different.

[0014] In one embodiment, at least one of the first muffler pipe and the second muffler pipe extends in a zigzag manner in a portion located in each of the muffler chambers.

[0015] In one embodiment, the multi-stage muffler structure includes a shell and a plurality of partitions arranged inside the shell, and all of the partitions are arranged in the shell at intervals along a first direction to divide the interior of the shell into a plurality of muffler chambers;

[0016] Wherein, each of the partitions is provided with a connecting hole, and the first muffler pipe is sequentially passed through all the connecting holes.

[0017] In one embodiment, the housing includes a structural body and a cover plate that can be spliced ​​together to form the muffler chamber;

[0018] Each of the partitions comprises a first partition part and a second partition part which can be connected to each other to form the connection hole, the first partition part is installed on the structural body, and the second partition part is installed on the cover plate.

[0019] A vehicle comprises the air filter as described above.

[0020] In one embodiment, the vehicle includes an engine and an air compressor, an air intake of one of the engine and the air compressor is connected to the air intake duct, and an air intake of the other is connected to an end of the first muffler pipe located outside the multi-stage muffler structure.

[0021] The above-mentioned air filter is provided with a plurality of closed silencer chambers in a multi-stage silencer structure, and the first silencer pipe is sequentially inserted into each silencer chamber. In this way, the noise generated by the air compressor enters the silencer chamber through the first silencer pipe, and is refracted, coupled and reduced in the silencer chamber, thereby reducing the noise in the first silencer pipe. The plurality of silencer chambers enable the noise in the first silencer pipe to be reduced multiple times, thereby ensuring the noise reduction effect on the noise waves generated by the air compressor. At the same time, by connecting the silencer chamber to the air intake duct, the noise waves generated by the engine during operation enter the multi-stage silencer structure through the air intake duct, and are refracted, coupled and reduced in the silencer chamber. In addition, since the noise waves generated by the air compressor and the noise waves generated by the engine will pass through the same silencer chamber, the two noise waves will cancel each other out in the silencer chamber, thereby improving the noise reduction effect of the multi-stage silencer structure. Through the above-mentioned air filter, the noise entering the air filter can be effectively attenuated, and the low-frequency silencing of the intake system at 80 to 500 Hz can be achieved by more than 20dB (A), and the silencing of key frequencies can be achieved by more than 40dB (A), thereby improving the sound quality in the cab and enhancing the driving comfort of users in the car cab. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of an air filter in one embodiment of the present invention;

[0023] Figure 2 for Figure 1 A cross-sectional schematic diagram of a multi-stage noise reduction structure in an embodiment;

[0024] Figure 3 for Figure 1 An exploded schematic diagram of a multi-stage noise reduction structure in an embodiment;

[0025] Figure 4 for Figure 1 A schematic structural diagram of a first muffler pipe of an air filter in an embodiment;

[0026] Figure 5 for Figure 1 A schematic structural diagram of a second muffler pipe of an air filter in an embodiment;

[0027] Figure 6 for Figure 1A schematic structural diagram of a partition of a multi-stage sound-absorbing structure in an embodiment;

[0028] Figure 7 for Figure 1 A schematic structural diagram of a cover plate of a multi-stage sound-absorbing structure in an embodiment.

[0029] Air filter body 100; air intake duct 101;

[0030] Multi-stage muffler structure 10; muffler chamber 11; first muffler chamber 111; second muffler chamber 112; third muffler chamber 113; shell 12; partition 13; connecting hole 14; mounting hole 15; structure body 16; cover plate 17; first partition part 18; second partition part 19;

[0031] First muffler pipe 20; first muffler hole 21;

[0032] Second muffler pipe 30; second muffler hole 31. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0038] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0039] See also Figure 1 and Figure 2 A vehicle provided by one embodiment of the present invention includes an engine, an air compressor, and an air filter for providing clean air to the engine and the air compressor.

[0040] The air filter includes an air filter body 100, a multi-stage muffler structure 10 and a first muffler pipe 20. An air intake duct 101 is formed inside the air filter body 100. The air intake duct 101 is connected to the air intake of the engine to input clean air to the engine. The multi-stage muffler structure 10 is installed on the air filter body 100 and has a plurality of muffler chambers 11 that are interconnected, wherein at least one muffler chamber 11 is connected to the air intake duct 101 so that the clean air in the air intake duct 101 can enter the muffler.

[0041] The first muffler pipe 20 is installed on the multi-stage muffler structure 10, and one end of the first muffler pipe 20 is located outside the multi-stage muffler structure 10 for connecting to the air inlet of the air compressor, and the other end passes through a plurality of muffler chambers 11 in sequence, and the portion of the first muffler pipe 20 located in each muffler chamber 11 has a first muffler hole 21. In this way, the clean air in the muffler chamber 11 will enter the air inlet of the air compressor through the first muffler pipe 20 to provide clean air to the air compressor, and the noise wave of the air compressor when it is running will pass through the first muffler pipe 20, be transmitted to the multi-stage muffler structure 10, and finally enter each muffler chamber 11 through the first muffler hole 21.

[0042] In the process of the noise wave entering the muffler cavity 11 from the first muffler hole 21 on the first muffler pipe 20, according to the principle of micro-hole noise reduction, the noise wave will first undergo the first noise reduction in the first muffler hole 21. After the noise wave enters the muffler cavity 11, the noise wave will be continuously refracted in the muffler cavity 11 and coupled with the noise wave that enters the muffler cavity 11 later, so that the noise waves can cancel each other out, thereby achieving the effect of noise reduction.

[0043] Specifically, when the noise wave of the air compressor enters the first silencer 20, it will move along the first silencer 20. When it encounters the first silencer hole 21 located in the first silencer chamber 11, part of the noise wave will enter the first silencer chamber 11 through the first silencer hole 21 and be reduced in noise by the silencer chamber 11. The remaining noise wave will continue to move along the first silencer 20 until it encounters the first silencer hole 21 located in the second silencer chamber 11, and then continue to separate part of the noise wave to enter the second silencer chamber 11 through the first silencer hole 21, and then be reduced in noise by the second silencer chamber 11. Similarly, multiple silencer chambers 11 will perform multiple noise reductions on the noise waves in the first silencer 20, thereby ensuring the noise reduction effect.

[0044] Furthermore, the noise waves generated by the engine during operation will be transmitted through the intake duct 101. Since the intake duct 101 is interconnected with the silencer chamber 11 in the multi-stage silencer structure 10, the noise waves generated by the engine during operation will be transmitted to the silencer chamber 11 through the intake duct 101, and reflected in the silencer chamber 11 to couple and offset each other, so as to achieve the effect of reducing the noise generated by the engine.

[0045] Furthermore, the noise waves generated by the air compressor and the noise waves generated by the engine will pass through one of the silencer chambers 11 at the same time. Since the noise waves generated by the air compressor and the noise waves generated by the engine enter the silencer chamber 11 through different paths, the two noise waves will cancel each other out during the reflection process in the silencer chamber 11, thereby improving the noise reduction effect of the multi-stage silencer structure 10.

[0046] The above-mentioned air filter is provided with a plurality of closed muffler chambers 11 in the multi-stage muffler structure 10, and the first muffler pipe 20 is sequentially inserted into each muffler chamber 11. In this way, the noise wave generated by the air compressor enters the muffler chamber 11 through the first muffler pipe 20, and is refracted, coupled and reduced in the muffler chamber 11, thereby reducing the noise wave in the first muffler pipe 20. The plurality of muffler chambers 11 enable the noise wave in the first muffler pipe 20 to be reduced multiple times, thereby ensuring the noise reduction effect of the noise wave generated by the air compressor. At the same time, by connecting the muffler chamber 11 to the intake pipe 101, the noise wave generated by the engine during operation enters the multi-stage muffler structure 10 through the intake pipe 101, and is refracted, coupled and reduced in the muffler chamber 11. In addition, since the noise wave generated by the air compressor and the noise wave generated by the engine will pass through the same muffler chamber 11, the two noise waves will cancel each other in the muffler chamber 11, thereby improving the noise reduction effect of the multi-stage muffler structure 10. Through the above-mentioned air filter, the noise waves entering the air filter can be effectively attenuated, and the low-frequency silencing of the intake system at 80 to 500 Hz can be achieved by more than 20dB (A), and the key frequency can achieve silencing of more than 40dB (A), thereby improving the sound quality in the cab and enhancing the driving comfort of users in the car cab.

[0047] It should be noted that, in other embodiments, the air intake pipe 101 may be used to supply air to the air intake of the air compressor, and the first muffler 20 may be used to supply air to the engine, which is not limited here.

[0048] In the embodiment of the present invention, in order to better reduce the noise waves in the intake duct 101, the air filter further includes a second muffler 30, one end of the second muffler 30 is located in the intake duct 101, and the other end is located in one of the muffler chambers 11, and the portion of the second muffler 30 located in each muffler chamber 11 has a second muffler hole 31, so that the noise waves in the second muffler 3030 can enter the muffler chamber 11 through the second muffler hole 3131. In this way, when the noise waves in the intake duct 101 enter the muffler chamber 11 through the second muffler 30, microporous noise reduction like the first muffler 20 will also be generated, and the noise waves in the intake duct 101 will be once reduced in the second muffler hole 31 and then enter the muffler chamber 11 for reflection and noise reduction, so that the second muffler 30 can improve the noise reduction effect of the noise waves in the intake duct 101, and also improve the noise reduction effect of the noise waves generated when the engine is working.

[0049] In some embodiments, the first silencer 20 is located at one end in the silencer chamber 11, and is located in the same silencer chamber 11 as the second silencer 30 is located at one end in the silencer chamber 11. In this way, the noise waves generated by the air compressor will be transmitted to the silencer chamber 11 through the first silencer 20, and the noise waves generated by the engine will be transmitted to the silencer chamber 11 through the second silencer 30. Therefore, the two noise waves will cancel each other out during the reflection process in the silencer chamber 11, so as to improve the noise reduction effect of the multi-stage silencer structure 10.

[0050] Specifically, the silencer chamber 11 includes three, namely the first silencer chamber 111, the second silencer chamber 112 and the third silencer chamber 113. The end of the first silencer tube 20 passes through the first silencer chamber 111 and the second silencer chamber 112 in sequence and is finally located in the third silencer chamber 113. One end of the second silencer tube 30 is located in the third silencer chamber 113.

[0051] For details in the embodiments, see Figure 4 The portion of the first silencer pipe 20 located in each silencer cavity 11 has a plurality of first silencer holes 21, and the number of the first silencer holes 21 in each silencer cavity 11 is different. The number of the first silencer holes 21 in each silencer cavity 11 can be adjusted according to the actual frequency and amplitude of the noise wave to meet the actual noise reduction requirements.

[0052] In some embodiments, see Figure 5 The portion of the second silencer pipe 30 located in the silencer chamber 11 has a plurality of second silencer holes 31, and all the second silencer holes 31 are arranged circumferentially along the axis of the second silencer pipe 30, so that the noise waves in the second silencer pipe 30 can more easily enter the silencer chamber 11 from one of the second silencer holes 31, and be reduced in noise through the second silencer holes 31, thereby improving the noise reduction effect on the noise waves.

[0053] In other embodiments, all the second silencer holes 31 can also be arranged at intervals along the longitudinal direction of the second silencer tube 30, so that the noise waves in the second silencer tube 30 can also more easily enter the silencer cavity 11 from one of the second silencer holes 31, and be reduced in noise through the second silencer holes 31, thereby improving the noise reduction effect on the noise waves.

[0054] In some embodiments, the first silencer 20 is located in the silencer cavity 11 and extends in a tortuous manner, so that the noise waves can be refracted multiple times and coupled with each other in the first silencer 20, thereby attenuating the noise waves and further improving the noise reduction effect of the multi-stage silencer structure 10.

[0055] Furthermore, the portion of the second silencer pipe 30 located in the silencer cavity 11 may also extend in a zigzag manner, thereby further improving the noise reduction effect of the multi-stage silencer structure 10 .

[0056] In some embodiments, see Figure 3 , Figure 6 and Figure 7 The multi-stage muffler structure 10 includes a shell 12 and a plurality of partitions 13 disposed inside the shell 12. All the partitions 13 are arranged in the shell 12 at intervals along a first direction to divide the inside of the shell 12 into a plurality of muffler cavities 11. A connection hole 14 is provided on each partition 13. The first muffler pipe 20 is sequentially passed through all the connection holes 14 so that one end of the first muffler pipe 20 can pass through the plurality of muffler cavities 11 in sequence.

[0057] Specifically, a mounting hole 15 connecting one of the silencer chambers 11 and the outside of the shell 12 is opened on the shell 12. The first silencer pipe 20 is passed through the mounting hole 15 and then passes through all the connecting holes 14 in sequence, so that the first silencer pipe 20 can pass through multiple silencer chambers 11 in sequence.

[0058] Specific to Figure 2 In the embodiment, the first direction is the up-down direction.

[0059] Specifically in the embodiment, in order to facilitate the assembly of the multi-stage silencer structure 10, the shell 12 includes a structural body 16 and a cover plate 17 that can be spliced ​​together to form the silencer chamber 11, and each partition 13 includes a first partition portion 18 and a second partition portion 19 that can be spliced ​​together to form a connecting hole 14. The first partition portion 18 is installed on the structural body 16, and the second partition portion 19 is installed on the cover plate 17.

[0060] In this way, the first partition portion 18 and the second partition portion 13 divide the connecting hole 14 into two half grooves. When the multi-stage silencer structure 10 needs to be assembled, the structural body 16 can be installed first, and then the first silencer pipe 20 can be passed through the half groove on the first partition portion 18. After that, the cover plate 17 and the structural body 16 can be spliced ​​together, and the first silencer pipe 20 can be fixed between the first partition portion 18 and the second partition portion 19, thereby completing the installation of the first silencer pipe 20.

[0061] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An air filter, characterized in that: include: An air filter body (100) is formed with an air intake duct (101) inside, and the air intake duct (101) is used to communicate with an air intake port of an engine; A multi-stage muffler structure (10) is installed on the air filter body (100) and has a plurality of muffler chambers (11) that are interconnected, wherein at least one of the muffler chambers (11) is connected to the air intake duct (101); A first silencer pipe (20) is installed on the multi-stage silencer structure (10), one end of the first silencer pipe (20) is located outside the multi-stage silencer structure (10) and is used to communicate with the air inlet of the compressor, and the other end passes through the plurality of silencer cavities (11) in sequence, and the portion of the first silencer pipe (20) located in each of the silencer cavities (11) has a first silencer hole (21), and the noise wave in the first silencer pipe (20) enters each of the silencer cavities (11) through the first silencer hole (21).

2. The air filter according to claim 1, characterized in that: The air filter further comprises a second silencer pipe (30), one end of the second silencer pipe (30) being located in the air intake duct (101), and the other end of the second silencer pipe (30) being located in one of the silencer chambers (11), and the portion of the second silencer pipe (30) located in each of the silencer chambers (11) having a second silencer hole (31), so that noise waves in the second silencer pipe (30) can enter the silencer chamber (11) through the second silencer hole (31).

3. The air filter according to claim 2, characterized in that: One end of the first muffler pipe (20) is located in the muffler cavity (11), and one end of the second muffler pipe (30) is located in the muffler cavity (11) is located in the same muffler cavity (11).

4. The air filter according to claim 3, characterized in that: The muffler chamber (11) comprises three muffler chambers, namely a first muffler chamber (111), a second muffler chamber (112) and a third muffler chamber (113); The end of the first muffler pipe (20) passes through the first muffler chamber (111) and the second muffler chamber (112) in sequence and is finally located in the third muffler chamber (113), and one end of the second muffler pipe (30) is located in the third muffler chamber (113).

5. The air filter according to claim 2, characterized in that: The portion of the first muffler pipe (20) located in each muffler cavity (11) has a plurality of the first muffler holes (21), and the number of the first muffler holes (21) in each muffler cavity (11) is different.

6. The air filter according to claim 2, characterized in that: At least one of the first muffler pipe (20) and the second muffler pipe (30) extends in a zigzag manner in the portion located in each of the muffler chambers (11).

7. The air filter according to claim 1, characterized in that: The multi-stage sound-absorbing structure (10) comprises a shell (12) and a plurality of partitions (13) arranged inside the shell (12), wherein all the partitions (13) are arranged in the shell (12) at intervals along a first direction, so as to divide the interior of the shell (12) into a plurality of sound-absorbing chambers (11); Each of the partitions (13) is provided with a connection hole (14), and the first muffler pipe (20) is sequentially passed through all of the connection holes (14).

8. The air filter according to claim 7, characterized in that: The shell (12) comprises a structural body (16) and a cover plate (17) which can be spliced ​​together to form the muffler chamber (11); Each of the partitions (13) comprises a first partition portion (18) and a second partition portion (19) which can be spliced ​​together to form the connection hole (14); the first partition portion (18) is mounted on the structural body (16), and the second partition portion (19) is mounted on the cover plate (17).

9. A vehicle, characterized in that: Comprising the air filter as described in any one of claims 1-8.

10. The vehicle according to claim 9, characterized in that The vehicle comprises an engine and an air compressor, wherein an air inlet of one of the engine and the air compressor is connected to the air inlet duct (101), and an air inlet of the other is connected to an end of the first muffler pipe (20) located outside the multi-stage muffler structure (10).

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