Noise reduction structure of automobile air conditioner pipeline

Abstract

The utility model relates to the technical field of automobile air conditioning systems, in particular to an automobile air conditioning pipeline noise reduction structure which comprises a main pipe body and a noise reduction cavity arranged on the main pipe body, the outer wall of the noise reduction cavity is coated with a composite sound insulation layer, and the composite sound insulation layer sequentially comprises a sound absorption cotton layer, a damping rubber layer and an aluminum foil reflecting layer from inside to outside. The silencing cavity is of an asymmetric double-cavity structure and comprises a front expansion cavity and a rear resonant cavity, the front expansion cavity and the rear resonant cavity are separated through an obliquely-arranged partition plate, and a plurality of air inlets and a plurality of air outlets are formed in the two ends of the silencing cavity respectively. A spiral flow deflector is arranged in the expansion cavity, and a perforated silencing cone is arranged in the resonant cavity. According to the automobile air conditioner pipeline noise reduction structure, the asymmetric double-cavity structure is combined with the spiral flow deflectors and the perforated noise reduction cone, low-frequency pulsation noise and medium-high frequency airflow noise can be effectively restrained, the functions of sound absorption, vibration reduction and reflection are achieved through the externally-arranged composite sound insulation layer, the automobile air conditioner pipeline noise reduction structure is not prone to aging after being used for a long time, and the overall service life is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of automobile air conditioning system technical field, specifically a kind of automobile air conditioning pipeline sound attenuation structure. BACKGROUND

[0002] Automobile air conditioning pipeline is an important component in air conditioning system, mainly used for transporting refrigerant (such as R134a or R1234yf), connecting compressor, condenser, evaporator and expansion valve and other key components. Its role is to ensure efficient circulation of refrigerant, realize temperature regulation in vehicle, while ensuring stable operation of air conditioning system. Since pressure pulsation and airflow noise are generated when refrigerant flows in pipeline, noise reduction design of pipeline directly affects NVH (noise, vibration and roughness of sound vibration) performance in vehicle.

[0003] Currently, airflow noise problem exists in automobile air conditioning pipeline, mainly from turbulent flow, pressure pulsation and pipeline resonance when refrigerant flows at high speed. Traditional noise reduction method mainly uses simple expansion chamber or sound-absorbing cotton wrapping, but the noise reduction effect is limited, and the volume of pipeline may be increased, affecting installation space. In addition, the existing sound attenuation structure often adopts symmetrical design, which has poor adaptability to different frequency noises, resulting in insufficient suppression of medium and high frequency noises, affecting the quietness in vehicle. Therefore, an efficient, compact and wide-frequency noise-adaptive sound attenuation structure is needed. UTILITY MODEL CONTENT

[0004] The utility model provides a kind of automobile air conditioning pipeline sound attenuation structure, to solve the problem of poor noise reduction effect, heavy structure and insufficient frequency band adaptability in prior art.

[0005] To solve the above technical problems, the utility model provides a kind of automobile air conditioning pipeline sound attenuation structure, including main pipe body and the sound attenuation cavity being arranged on main pipe body, the outer wall of sound attenuation cavity is covered with composite sound insulation layer, the composite sound insulation layer includes sound-absorbing cotton layer, damping rubber layer and aluminum foil reflection layer from inside to outside in sequence;The sound attenuation cavity adopts asymmetric double-cavity structure, including front expansion chamber and rear resonance cavity, two cavities are separated by the inclined partition, and multiple air inlets and multiple air outlets are respectively arranged at two ends of sound attenuation cavity;Spiral guide vane is arranged in expansion chamber, and perforated sound attenuation cone is arranged in resonance cavity.

[0006] As a preferred technical scheme of the utility model, gradually increasing transition section is arranged at the connection between main pipe body and sound attenuation cavity, and honeycomb sound-absorbing pad is arranged between main pipe body and sound attenuation cavity.

[0007] As a preferred technical scheme of the utility model, air inlets and air outlets are annular array at two ends of sound attenuation cavity.

[0008] As a preferred technical scheme of the utility model, the sound-absorbing cotton layer has a thickness of 3-5 mm and a gradient density, the density being the largest near the outer wall of the sound-absorbing cavity and gradually decreasing outward.

[0009] As a preferred technical scheme of the utility model, the partition plate and the main pipe body axis form an included angle of 30-60 degrees, and the partition plate is connected with the expansion cavity and the resonance cavity through a plurality of through holes.

[0010] As a preferred technical scheme of the utility model, the pitch of the spiral flow guide vane gradually increases along the airflow direction, and the height of the spiral flow guide vane gradually decreases with the change of the pitch, forming a variable cross-section spiral channel.

[0011] As a preferred technical scheme of the utility model, the perforated sound-absorbing cone is a multi-stage stepped conical structure, including at least three conical segments with different cone angles, and each of the conical segment surfaces is provided with micro-perforations arranged in a staggered manner, and the diameters of the micro-perforations of adjacent conical segments differ by 0.2-0.5 mm.

[0012] Compared with the prior art, the utility model has the advantages that:

[0013] The asymmetric double-cavity structure of the automobile air conditioner pipeline sound-absorbing structure in combination with the spiral flow guide vane and the perforated sound-absorbing cone can effectively suppress low-frequency pulsating noise and medium-high frequency airflow noise, and through the externally arranged composite sound insulation layer, the sound-absorbing, vibration-reducing and reflecting functions are combined, the long-term use is not prone to aging, the overall service life is improved, and the optimized sound-absorbing cavity volume is small, facilitating installation and being suitable for the automobile air conditioning system with limited space. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a structural diagram of the utility model of a kind of automobile air conditioner pipeline sound-absorbing structure.

[0015] Figure 2 It is a sectional stereogram of the utility model of a kind of automobile air conditioner pipeline sound-absorbing structure.

[0016] Figure 3 It is an enlarged view of structure A of the utility model of a kind of automobile air conditioner pipeline sound-absorbing structure.

[0017] Figure 4 It is a perforated sound-absorbing cone of the utility model of a kind of automobile air conditioner pipeline sound-absorbing structure.

[0018] As shown in the figure:

[0019] 1, main pipe body; 2, sound attenuation cavity; 3, composite sound insulation layer; 4, sound absorbing cotton layer; 5, damping rubber layer; 6, aluminum foil reflection layer; 7, expansion cavity; 8, resonance cavity; 9, partition; 10, spiral guide vane; 11, perforated sound attenuation cone; 12, transition section; 13, sound absorbing pad; 14, through hole; 15, cone section; 16, micro-perforation; 17, air inlet; 18, air outlet. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0021] In the description of the utility model, it should be explained that, unless otherwise explicitly specified and limited, the terms "mounting", "provided with", "connection" and the like should be understood in a broad sense. For example, "connection" can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, and can be the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.

[0022] Embodiment 1

[0023] As shown in the description accompanying drawings Figures 1-3 A sound attenuation structure of automobile air conditioning pipeline, comprising a main pipe body 1 and a sound attenuation cavity 2 arranged on the main pipe body 1, the outer wall of the sound attenuation cavity 2 is covered with a composite sound insulation layer 3, the composite sound insulation layer 3 comprises a sound absorbing cotton layer 4, a damping rubber layer 5 and an aluminum foil reflection layer 6 from inside to outside in sequence, the thickness of the sound absorbing cotton layer 4 is 3-5mm and the density is gradiently changed, the density is the largest near the outer wall of the sound attenuation cavity 2 and gradually decreases outward, a transition section 12 with gradually increasing inner diameter is arranged at the connection between the main pipe body 1 and the sound attenuation cavity 2, a honeycomb-shaped sound absorbing pad 13 is arranged between the main pipe body 1 and the sound attenuation cavity 2, and the noise inside the pipeline is absorbed and conducted through the sound absorbing pad 13.

[0024] In the utility model, the sound attenuation cavity 2 adopts an asymmetric double-cavity structure, comprising a front expansion cavity 7 and a rear resonance cavity 8, the two cavities are separated by an inclined partition 9, the partition 9 and the axis of the main pipe body 1 form an angle of 30-60 degrees, the partition 9 is communicated with the expansion cavity 7 and the resonance cavity 8 through a plurality of through holes 14, a plurality of air inlets 17 and a plurality of air outlets 18 are arranged at the two ends of the sound attenuation cavity 2 respectively, and the air inlets 17 and the air outlets 18 are annular arrays arranged at the two ends of the sound attenuation cavity 2.

[0025] In the utility model, the expansion cavity 7 is internally provided with a spiral flow guide vane 10, the pitch of the spiral flow guide vane 10 gradually increases along the air flow direction, the height of the spiral flow guide vane 10 gradually decreases with the change of the pitch, a variable cross-section spiral channel is formed, and the resonance cavity 8 is internally provided with a perforated sound attenuation cone 11.

[0026] As shown in the accompanying drawings Figure 4 The perforated sound attenuation cone 11 is a multi-stage stepped conical structure, and includes at least three conical sections 15 with different cone angles, and each conical section 15 is internally provided with a plurality of micro perforations 16 arranged in a staggered manner, and the diameters of the micro perforations 16 of adjacent conical sections 15 are different by 0.2-0.5 mm.

[0027] In the utility model, the refrigerant flow generates heat transfer, and the generated air flow enters the expansion cavity 7 from the air inlet 17, the air flow is guided to rotate by the spiral flow guide vane 10 in the expansion cavity 7, and the turbulent flow is reduced; the resonance cavity 8 generates acoustic impedance matching through the micro perforation structure of the perforated sound attenuation cone, consumes noise energy, and then the air flow is discharged from the air outlet 18 at the other end, the asymmetric double-cavity design is respectively used for low-frequency (expansion cavity 7) and medium-high frequency (resonance cavity 8) noise, full-band noise reduction is realized, high-frequency noise is absorbed through the sound-absorbing pad 13 and the composite sound insulation layer 3, the damping rubber layer 5 suppresses vibration, noise generated in the refrigerant flow process is absorbed, and the aluminum foil layer protects the outside.

[0028] The utility model and the implementation mode thereof are described above, and the description is not restrictive, and the implementation mode shown in the specific embodiment is only one of the implementation modes of the utility model, and the actual structure is not limited thereto. In summary, if a person skilled in the art is inspired thereby, without departing from the creative purpose of the utility model, without creative design, similar structure modes and embodiments of the technical scheme are not creative, and all should belong to the protection scope of the utility model.

Claims

1. An automobile air conditioning pipeline silencing structure, comprising a main pipe body (1) and a silencing cavity (2) arranged on the main pipe body (1), characterized in that: the outer wall of the silencing cavity (2) is coated with a composite sound insulation layer (3), which comprises, from inside to outside, an acoustic cotton layer (4), a damping rubber layer (5) and an aluminum foil reflection layer (6); the silencing cavity (2) adopts an asymmetric double-cavity structure, comprising a front expansion cavity (7) and a rear resonance cavity (8), and the two cavities are separated by an inclined partition plate (9), and the two ends of the silencing cavity (2) are respectively provided with a plurality of air inlet ports (17) and a plurality of air outlet ports (18); the expansion cavity (7) is provided with a spiral guide vane (10), and the resonance cavity (8) is provided with a perforated silencing cone (11).

2. The automobile air conditioning pipeline silencing structure according to claim 1, characterized in that: The main pipe body (1) and the silencing cavity (2) are connected at a transition section (12) with gradually increasing inner diameter, and the main pipe body (1) and the silencing cavity (2) are provided with a honeycomb-shaped sound absorption pad (13).

3. The automobile air conditioner pipe silencing structure according to claim 1, characterized in that: The air inlet ports (17) and the air outlet ports (18) are annular arrays located at the two ends of the silencing cavity (2).

4. The automobile air conditioner pipe silencing structure according to claim 1, characterized in that: The thickness of the acoustic cotton layer (4) is 3-5mm and the density varies in a gradient manner, the density being the largest near the outer wall of the silencing cavity (2) and gradually decreasing outward.

5. The automobile air conditioning pipe silencing structure according to claim 1, characterized in that: The partition plate (9) and the main pipe body (1) axis form an angle of 30-60 degrees, and the partition plate (9) is connected to the expansion cavity (7) and the resonance cavity (8) through a plurality of through holes (14).

6. The automobile air conditioning pipe silencing structure according to claim 1, characterized in that: The pitch of the spiral guide vane (10) gradually increases along the airflow direction, and the height of the spiral guide vane (10) decreases with the change of the pitch, forming a variable cross-section spiral channel.

7. The automobile air conditioning pipe silencing structure according to claim 1, characterized in that: The perforated silencing cone (11) is a multi-stage stepped conical structure, comprising at least three conical segments (15) with different cone angles, and each conical segment (15) is provided with a plurality of micro-perforations (16) arranged in a staggered manner, and the diameters of the micro-perforations (16) of adjacent conical segments (15) differ by 0.2-0.5mm.

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