Low noise ventilation duct

Abstract

The utility model relates to the technical field of automobile ventilation pipe, and disclose a low noise ventilation pipe, including pipeline body, the pipeline wall of pipeline body adopts the composite layer structure, from inside to outside includes sound absorption layer, cavity layer and damping sound insulation layer in proper order, the microperforated structure of array distribution is seted up on sound absorption layer, the cavity of array arrangement has on cavity layer, the damping sound insulation layer is butyl rubber - aluminium foil composite layer, the pipeline inner wall of pipeline body is equipped with spiral flow guide groove spirally. The utility model through spiral flow guide groove restrains turbulent flow and the microperforated structure and cavity seted up on pipeline body composite layer, realizes full frequency band noise reduction, optimizes flow channel structure simultaneously, effectively reduces the wind resistance relative to traditional muffler, and then reduces the noise, increases the comfort degree, and through the integration of sound absorption layer, cavity layer and damping layer of composite layer structure in the pipe wall, need not to hang the muffler, saves the installation space.

Description

Technical Field

[0001] This utility model relates to the field of automotive ventilation pipe technology, and more specifically to a low-noise ventilation pipe. Background Technology

[0002] The ventilation ducts in a car are important components of the air conditioning and ventilation system, acting like the vehicle's "breathing ducts." They are primarily responsible for delivering regulated air from the air conditioning unit to the designated air vents inside the cabin.

[0003] A search revealed Chinese patent CN216993819U, which discloses an automotive ventilation duct. This device allows multiple ventilation ducts with different functions to be combined together, reducing the space occupied by the automotive ventilation duct, facilitating maintenance and repair, and extending the service life of the automotive ventilation duct. However, when the ventilation duct is transporting airflow, it often generates eddies and pressure pulsations due to sudden changes in flow velocity at the inner wall of the duct, bends, diameter changes, or valves, resulting in significant noise and affecting comfort. Utility Model Content

[0004] In order to overcome the above-mentioned defects of the prior art, the present invention provides a low-noise ventilation duct to solve the problems existing in the background art.

[0005] This utility model provides the following technical solution: a low-noise ventilation pipe, including a pipe body, the pipe wall of the pipe body adopts a composite layer structure, which includes a sound-absorbing layer, a cavity layer and a damping sound insulation layer from the inside to the outside. The sound-absorbing layer has an array of micro-perforated structures, the cavity layer has an array of cavities, the damping sound insulation layer is a butyl rubber-aluminum foil composite layer, and the inner wall of the pipe body is provided with a spiral flow guide groove in a spiral shape.

[0006] As a further embodiment of this utility model, the cavity is cone-shaped, and the cone-shaped cavities of the cavity layer are distributed in a honeycomb pattern on the cavity layer.

[0007] As a further embodiment of this invention, the surface of the sound-absorbing layer is covered with a hydrophobic coating.

[0008] As a further embodiment of this utility model, both ends of the pipe body are bonded with connecting flanges, and an annular groove is provided on one side of the connecting flange, with a sealing ring bonded in the annular groove.

[0009] As a further embodiment of this invention, the width of the sealing ring is slightly smaller than the width of the ring groove, and the thickness of the sealing ring is slightly larger than the thickness of the ring groove.

[0010] As a further embodiment of this utility model, a guide vane is provided on the inner side of the bend section of the pipe body, and the guide vane has the same direction as the bend section of the pipe body.

[0011] As a further embodiment of this invention, the cross-section of the spiral guide groove is trapezoidal.

[0012] As a further embodiment of this invention, the sealing ring is a damping rubber strip.

[0013] The technical effects and advantages of this utility model are as follows: 1. This utility model achieves full-band noise reduction by suppressing turbulence through spiral guide grooves and micro-perforated structures and cavities opened on the composite layer of the pipe body. At the same time, it optimizes the flow channel structure, effectively reducing wind resistance compared with traditional silencers, thereby reducing noise and improving comfort.

[0014] 2. This utility model integrates the sound-absorbing layer, cavity layer and damping layer of the composite layer structure into the pipe wall, eliminating the need for an external silencer and saving installation space.

[0015] 3. This utility model reduces local pressure loss, lowers the power consumption of the fan, and reduces energy consumption through the use of bent guide vanes and optimized flow channel design. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0017] Figure 2 This is a cross-sectional structural diagram of the pipe body of this utility model.

[0018] Figure 3 This is a schematic diagram of the pipe wall structure of the pipe body of this utility model.

[0019] The attached diagram is labeled as follows: 1. Pipe body; 101. Sound-absorbing layer; 102. Cavity layer; 103. Damping sound insulation layer; 2. Connecting flange; 3. Annular groove; 4. Sealing ring; 5. Guide vane; 6. Spiral guide groove; 7. Cavity; 8. Hydrophobic coating. Detailed Implementation

[0020] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. This utility model is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] Reference Figures 1-3This utility model provides a low-noise ventilation pipe, including a pipe body 1. The pipe wall of the pipe body 1 adopts a composite layer structure, which includes a sound-absorbing layer 101, a cavity layer 102 and a damping sound insulation layer 103 from the inside to the outside. The sound-absorbing layer 101 has an array of micro-perforated structures. The cavity layer 102 has cavities 7 arranged in an array. The damping sound insulation layer 103 is a butyl rubber-aluminum foil composite layer. The inner wall of the pipe body 1 is provided with a spiral guide groove 6 in a spiral shape. The cross-section of the spiral guide groove 6 is trapezoidal.

[0022] By suppressing turbulence through the spiral guide channel 6 and the micro-perforated structure and cavity 7 opened on the composite layer of the pipe body 1, noise reduction is achieved across the entire frequency band. At the same time, the flow channel structure is optimized, which effectively reduces wind resistance compared with traditional silencers, thereby reducing noise and increasing comfort.

[0023] The spiral guide groove 6 on the inner wall of the pipe guides the airflow along the spiral trajectory, forming a stable swirling flow field. The trapezoidal cross section reduces airflow stripping and suppresses the generation of turbulent vortices. The pitch and pipe diameter are matched to balance the airflow propulsion force and centrifugal force, reducing high-frequency whistling.

[0024] Furthermore, the cavity 7 is cone-shaped, and the cone-shaped cavities 7 of the cavity layer 102 are distributed in a honeycomb pattern on the cavity layer 102.

[0025] The sound-absorbing layer 101, cavity layer 102 and damping sound insulation layer 103 of the composite layer structure are integrated into the pipe wall, eliminating the need for an external silencer and saving installation space.

[0026] Furthermore, the surface of the sound-absorbing layer 101 is covered with a hydrophobic coating 8.

[0027] Solid-borne sound transmission is blocked. The butyl rubber-aluminum foil composite layer forms a high-damping constraint layer. The butyl rubber converts the mechanical energy of vibration into heat energy, blocking the transmission of pipeline vibration to the building structure and reducing solid-borne noise.

[0028] In this utility model, both ends of the pipe body 1 are bonded with connecting flanges 2, and a ring groove 3 is provided on one side of the connecting flange 2, and a sealing ring 4 is bonded in the ring groove 3.

[0029] Furthermore, the width of the sealing ring 4 is slightly smaller than the width of the ring groove 3, and the thickness of the sealing ring 4 is slightly greater than the thickness of the ring groove 3.

[0030] Furthermore, the sealing ring 4 is a damping rubber strip, which is made of a composite material of EPDM rubber and silicone.

[0031] In this utility model, a guide vane 5 is provided on the inner side of the bend section of the pipe body 1, and the guide vane 5 has the same direction as the bend section of the pipe body 1.

[0032] The guide vanes 5 eliminate the airflow separation zone and reduce vortex noise.

[0033] By using the elbow guide vanes 5, the optimized flow channel design reduces local pressure loss, lowers the power required for the fan, and reduces energy consumption.

[0034] The use of this utility model involves the following steps: S1: The spiral guide groove 6 on the inner wall of the pipe guides the airflow along the spiral trajectory to form a stable swirling flow field. The trapezoidal cross section reduces airflow stripping and suppresses the generation of turbulent vortices. The pitch and pipe diameter are matched to balance the airflow propulsion force and centrifugal force, reducing high-frequency whistling. S2: Solid-borne sound blocking. The butyl rubber-aluminum foil composite layer forms a high-damping constraint layer. The butyl rubber converts the mechanical energy of vibration into heat energy, blocking the transmission of pipe vibration to the building structure and reducing solid noise. S3: Guide vanes 5 eliminate the airflow separation zone and reduce vortex noise.

[0035] Finally, the following points should be noted: In the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection" and "linkage" should be interpreted broadly, and can be mechanical or electrical connection, or internal connection between two components, or direct connection. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may change. The electronic components and modules used in this utility model can all be parts that are commonly used in the market and can achieve the specific functions in this case. The specific models and sizes can be selected and adjusted according to actual needs. The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

Claims

1. A low-noise ventilation duct, comprising a duct body (1), characterized in that: The pipe wall of the pipe body (1) adopts a composite layer structure, which includes a sound-absorbing layer (101), a cavity layer (102) and a damping sound insulation layer (103) from the inside to the outside. The sound-absorbing layer (101) has an array of micro-perforated structures. The cavity layer (102) has an array of cavities (7). The damping sound insulation layer (103) is a butyl rubber-aluminum foil composite layer. The inner wall of the pipe body (1) is provided with a spiral guide groove (6) in a spiral shape.

2. The low-noise ventilation duct according to claim 1, characterized in that: The cavity (7) is cone-shaped, and the cone-shaped cavities (7) of the cavity layer (102) are distributed in a honeycomb pattern on the cavity layer (102).

3. A low-noise ventilation duct according to claim 1, characterized in that: The surface of the sound-absorbing layer (101) is covered with a hydrophobic coating (8).

4. A low-noise ventilation duct according to claim 1, characterized in that: Both ends of the pipe body (1) are bonded with connecting flanges (2), and an annular groove (3) is provided on one side of the connecting flange (2), and a sealing ring (4) is bonded in the annular groove (3).

5. A low-noise ventilation duct according to claim 4, characterized in that: The width of the sealing ring (4) is slightly smaller than the width of the ring groove (3), and the thickness of the sealing ring (4) is slightly greater than the thickness of the ring groove (3).

6. A low-noise ventilation duct according to claim 4, characterized in that: The inner side of the bend section of the pipe body (1) is provided with a guide vane (5), and the guide vane (5) has the same direction as the bend section of the pipe body (1).

7. A low-noise ventilation duct according to claim 1, characterized in that: The cross-section of the spiral guide groove (6) is trapezoidal.

8. A low-noise ventilation duct according to claim 5, characterized in that: The sealing ring (4) is a damping rubber strip.

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