Noise reduction device, volute and range hood duct system

Abstract

The present invention provides a noise reduction device, a volute and a range hood air duct system, which relate to the technical field of kitchen appliances. The noise reduction device comprises a porous plate and a cover plate; a vibration-damping particle layer and / or an air bag layer filled with inert gas is arranged between the porous plate and the cover plate; the volute comprises the aforementioned noise reduction device, and the range hood air duct system comprises the aforementioned volute. The present invention has at least the beneficial effects of excellent noise reduction effect, simple implementation, cost saving, good versatility, and the noise reduction effect is not easy to fail.

Description

Technical Field

[0001] The present invention relates to the technical field of kitchen appliances, and in particular to a noise reduction device, a volute and a range hood air duct system. Background Art

[0002] The noise generated by the range hood during operation is mainly composed of two parts. The first is the vibration noise generated by the vibration of the range hood air duct system itself. The second is the aerodynamic noise generated by the continuous flow of air in the operation process and the flow inside the air duct system. Specifically, the noise-generating components of the range hood mainly include the motor, impeller, and the air duct system mainly composed of a volute. Driven by the motor, the impeller stably inputs the airflow into the air duct system. The airflow separates from the impeller surface and is discharged from the inlet to the outlet through the air duct system. In the process, the vibration of the motor and the separation of the airflow from the impeller surface and the volute surface can generate a certain degree of noise.

[0003] With the continuous advancement of technology, people have higher and higher requirements for the noise performance level of range hoods. At present, there are three main effective ways to reduce the noise of the range hood air duct system:

[0004] First, optimize the range hood air duct system itself, mainly including modifying the volute profile, optimizing the volute tongue, changing the shape and number of impellers. The specific modification method is generally calculated by equations. Although this method is relatively stable and will not cause noise reduction performance degradation during use, its own optimization must match other components in the air duct. In addition, the modification needs to be performed on the original mold, which will increase the mold cost and the problem of too many modified parts. More importantly, using this method for noise reduction cannot achieve a significant noise reduction effect;

[0005] Second, add a guide device inside the range hood air duct system. The main implementation method is to design some components according to the internal structure of the household range hood and the path of gas flow, and install the components to the corresponding parts to guide the airflow, so that the scattered and colliding airflows can be as orderly as possible, thereby reducing the noise caused by turbulence. This solution has a relatively good noise reduction effect, but because it is implemented according to the internal structure of the range hood, the same guide structure installed in another slightly different range hood may have no effect at all, resulting in poor versatility;

[0006] Third, perforate the surface of the air duct system to add sound-absorbing cotton. First, perform laser micro-perforation on the surface of the volute of the air duct system to make its surface have a regularly arranged array of small holes, and then attach the sound-absorbing cotton thereto and fix it with glue or a stainless steel bracket to achieve the effect of absorbing the radiated noise from the surface of the air duct system. This method consumes the energy of sound during the propagation of sound, thereby achieving the purpose of noise reduction. Although this method is simpler to implement, more cost-effective, and more versatile than the first two methods, and can achieve a more effective noise reduction function, this noise reduction scheme mainly relies on the tiny holes inside the sound-absorbing cotton to absorb sound, so during use, the sound-absorbing cotton gradually absorbs oil droplets, resulting in the gradual loss of noise reduction effect. In addition, the noise reduction effect that can be achieved by this noise reduction method is not very good, that is, there is still a technical problem of limited noise reduction effect.

[0007] At present, the noise reduction design related structures applied to the air duct system have at least the technical problems of not being able to simultaneously achieve effective noise reduction effect, simple implementation, cost saving, good versatility, and noise reduction effect that is not easily lost. Summary of the invention

[0008] The object of the present invention is to provide a noise reduction device, a volute and a range hood air duct system, which at least have the beneficial effects of excellent noise reduction effect, simple implementation, cost saving, good versatility, and the noise reduction effect is not easy to fail.

[0009] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0010] In a first aspect, an embodiment of the present invention provides a noise reduction device, comprising a porous plate and a cover plate; a vibration-damping particle layer and / or an airbag layer filled with an inert gas is arranged between the porous plate and the cover plate, wherein "and / or" means that the vibration-damping particle layer and the aforementioned airbag layer are arranged between the porous plate and the cover plate at the same time or selectively.

[0011] In an optional embodiment, the vibration-damping particles in the vibration-damping particle layer are made of loose porous sound-absorbing material.

[0012] In an optional embodiment, the vibration-damping particle layer includes at least two spherical particles with different diameters.

[0013] In an optional embodiment, the diameter of each opening on the porous plate is 4.9mm-5.1mm, and / or the spacing between two adjacent openings on the porous plate is 11.4mm-11.6mm, wherein "and / or" means that "the diameter of each opening on the porous plate" and "the spacing between two adjacent openings on the porous plate" are selected or simultaneously set to the above-mentioned corresponding lengths.

[0014] In an optional embodiment, the noise reduction device includes a vibration-damping particle layer and an airbag layer filled with an inert gas, the vibration-damping particle layer is arranged between the porous plate and the airbag layer, and the airbag layer is arranged between the vibration-damping particle layer and the cover plate.

[0015] In an optional embodiment, the airbag layer and the cover plate are spaced apart from each other to form a first cavity between the airbag layer and the cover plate.

[0016] In an optional embodiment, the volume ratio of the air in the first cavity, the vibration-damping particles in the vibration-damping particle layer, and the airbags in the airbag layer is 1:5:6 to 1.5:5:15.

[0017] In an optional embodiment, the edge of the porous plate is provided with a flange, and the cover plate is connected to the flange.

[0018] In a second aspect, an embodiment of the present invention provides a volute, comprising a volute body and a noise reduction device according to any one of the aforementioned embodiments, wherein the porous plate is installed on the outer wall of the volute body, and the porous plate and the outer wall surface of the volute body are spaced apart from each other to form a second cavity between the outer wall of the volute body.

[0019] In a third aspect, an embodiment of the present invention provides a range hood air duct system, comprising the volute in the aforementioned embodiment.

[0020] The embodiments of the present invention can achieve the following beneficial effects:

[0021] In a first aspect, an embodiment of the present invention provides a noise reduction device, comprising a porous plate and a cover plate; a vibration-damping particle layer and / or an airbag layer filled with an inert gas is arranged between the porous plate and the cover plate, wherein "and / or" means that the vibration-damping particle layer and the aforementioned airbag layer are arranged between the porous plate and the cover plate at the same time or selectively.

[0022] In the embodiment of the present invention, firstly, when the sound wave propagates to the porous plate, it will cause the air inside the openings on the porous plate to oscillate, thereby effectively converting the energy of the sound wave vibration into the energy of the air oscillation, and thus effectively reducing the noise; secondly, the openings on the porous plate and the air at the surrounding boundaries form a structure similar to a Helmholtz resonator, which can form a resonant sound-absorbing structure with better effects, which can effectively absorb low-frequency noise, and then absorb the noise propagated thereto together with the porous plate, and the absorbed noise frequency band is mainly low-frequency; thirdly, the sound wave passes through the above-mentioned vibration-damping particle layer and / or the air bag layer filled with inert gas arranged between the porous plate and the cover plate, thereby further absorbing the noise; finally, the cover plate itself also absorbs a certain amount of noise.

[0023] The noise reduction device provided in the embodiment of the present invention has a good noise reduction effect and can be applied to the part of the air duct system structure away from oil pollution. It has at least the beneficial effects of excellent noise reduction effect, simple implementation, cost saving, good versatility, and its noise reduction effect will not be affected by oil pollution and is not easy to fail.

[0024] In addition, the second aspect of the embodiment of the present invention further provides a volute, including the noise reduction device provided by the first aspect mentioned above, and the third aspect of the embodiment of the present invention further provides a range hood air duct system, including the volute provided by the second aspect mentioned above; the volute and range hood air duct system provided by the embodiment of the present invention can achieve all the beneficial effects that can be achieved by the noise reduction device provided by the first aspect mentioned above. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A cross-sectional view of the overall structure of the noise reduction device provided by an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of the sound wave absorption or reflection principle of the gas, the vibration-damping particles and the airbag in the first cavity of the volute provided in an embodiment of the present invention;

[0028] Figure 3 An equivalent circuit analysis diagram of the noise reduction principle of the gas, vibration-damping particles, and airbag volume ratio in the first cavity of the volute provided in an embodiment of the present invention;

[0029] Figure 4 An exploded view of the overall structure of the volute provided in an embodiment of the present invention, wherein the vibration-damping particles are not shown;

[0030] Figure 5 A cross-sectional view of a second cavity formed between a porous plate in a volute and an outer side wall of the volute provided in an embodiment of the present invention;

[0031] Figure 6 A cross-sectional view of the overall structure of the volute provided in an embodiment of the present invention;

[0032] Figure 7 for Figure 6 A magnified view of the local structure of area A in the middle.

[0033] Icon: 1-volute body; 11-extended edge; 101-first cavity; 102-second cavity; 110-porous plate; 111-flange; 120-cover plate; 131-vibration-damping particle layer; 132-airbag layer. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0037] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invented product is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" 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 it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0040] Embodiment 1

[0041] This embodiment provides a noise reduction device, referring to Figure 1 The noise reduction device includes a porous plate 110 and a cover plate 120; a vibration-damping particle layer 131 and / or an air bag layer 132 filled with an inert gas is arranged between the porous plate 110 and the cover plate 120.

[0042] Specifically, this embodiment has the following implementation modes:

[0043] The first embodiment is: a vibration-damping particle layer 131 is provided between the porous plate 110 and the cover plate, and the above-mentioned airbag layer 132 filled with inert gas is not provided; the second embodiment is: an airbag layer 132 filled with inert gas is provided between the porous plate 110 and the cover plate, and the above-mentioned vibration-damping particle layer 131 is not provided; the third embodiment is: both the vibration-damping particle layer 131 and the airbag layer 132 filled with inert gas are provided between the porous plate 110 and the cover plate.

[0044] Among them, in the vibration-damping particle layer 131, the gaps between adjacent vibration-damping particles form a plurality of irregular cavities, and the air inside the cavity can oscillate under the action of sound waves, thereby effectively converting the energy of the sound waves into the heat energy of air oscillation. Since the noise band of the intermediate frequency is relatively wide, the above-mentioned irregular air cavity structure can just cover the noise of the intermediate frequency band as widely as possible and effectively absorb it; in the airbag layer 132, the inert gas itself has a relatively good sound insulation performance. When the sound wave passes through the inert gas, the amplitude of the inert gas itself is smaller than that of the air. Therefore, the inert gas, as a sound transmission medium, can effectively weaken the vibration energy of the sound wave. Among them, the airbag layer 132 has a relatively good sound insulation performance. When the sound wave passes through the inert gas, the amplitude of the inert gas itself is smaller than that of the air. Therefore, the inert gas, as a sound transmission medium, can effectively weaken the vibration energy of the sound wave. The airbag of the bag layer 132 can be made of but not limited to butyl rubber, nitrile or silicone, etc. Butyl rubber is preferably used, which has good air tightness and damping function, and can effectively convert mechanical vibration energy into heat energy, thereby dissipating the vibration energy of the air duct system structure installed with the noise reduction device, and reducing part of the noise generated by mechanical vibration. In addition, when sound passes through the interface between different media, the sound transmission between two different media will be attenuated. The air, the airbag, and the inert gas inside the airbag can form multiple heterogeneous interfaces, which can also further dissipate the energy of the sound. The inert gas in the airbag can be helium or other inert gases.

[0045] In the present embodiment, firstly, when the sound wave propagates to the porous plate 110, it will cause the air inside the openings on the porous plate 110 to oscillate, thereby effectively converting the energy of the sound wave vibration into the energy of the air oscillation, thereby effectively reducing the noise; secondly, the openings on the porous plate 110 and the air at the surrounding boundaries form a structure similar to a Helmholtz resonator, which can form a resonant sound-absorbing structure with better effect, which can effectively absorb low-frequency noise, and then absorb the noise propagated thereto together with the porous plate 110, and the absorbed noise frequency band is mainly low-frequency; thirdly, the sound wave passes through the above-mentioned vibration-damping particle layer 131 and / or the air bag layer 132 filled with inert gas arranged between the porous plate 110 and the cover plate 120, thereby further absorbing the noise; finally, the cover plate 120 itself also absorbs a certain amount of noise.

[0046] The noise reduction device provided in this embodiment has a good noise reduction effect and can be applied to the parts of the air duct system structure that are far away from oil pollution. It has at least the beneficial effects of excellent noise reduction effect, simple implementation, cost saving, good versatility, and its noise reduction effect will not be affected by oil pollution and is not easy to fail.

[0047] In the present embodiment, the specific structural forms of the vibration-damping particles in the above-mentioned vibration-damping particle layer 131 are various, such as but not limited to solid particles or hollow particles made of sponge material, rubber material or other materials. In the present embodiment, the vibration-damping particles in the above-mentioned vibration-damping particle layer 131 are made of sponge or other loose porous sound-absorbing materials. The air inside the pores of the vibration-damping particles made of loose porous sound-absorbing materials will vibrate under the vibration of sound waves, and convert the energy of sound waves into heat energy generated by air viscous friction, thereby effectively absorbing the energy of intermediate frequency noise. When sound passes through the interface between different media, sound transmission between two different media will also be attenuated. The heterogeneous interface between the vibration-damping particles and the air formed between the air in the pores of the vibration-damping particles themselves and the vibration-damping particle entities can further effectively attenuate the energy of sound when passing through the interface, thereby reducing noise.

[0048] In this embodiment, the vibration-damping particle layer 131 includes at least two spherical particles with different diameters, for example but not limited to four sizes of spherical particles, namely 10 mm, 8 mm, 6 mm, and 4 mm, and the four sizes of small balls are evenly mixed. After mixing, squeezing is allowed between the small balls. The air in the pores formed by the contact between the multiple spherical particles and the heterogeneous interfaces formed between the spherical particles and the air can further effectively attenuate the energy of sound when passing through the interface, thereby reducing noise; and these spherical particles themselves have smooth edges and small volumes, and can be displaced slightly in a limited space with vibration. When the noise reduction device is installed on a volute or other air duct system structure, the energy of the vibration of the air duct system structure can be converted into heat energy through the friction generated by the displacement of these spherical particles, thereby consuming the energy of the vibration of the air duct system structure on which the noise reduction device is installed, thereby further reducing the noise.

[0049] In the present embodiment, the diameter of the openings on the porous plate 110 and the spacing between two adjacent openings can be arranged as needed. In order to improve the effect of the above-mentioned structure of the present embodiment on absorbing noise in the medium and high frequency bands, in a more preferred implementation manner of the present embodiment, the diameter of each opening on the porous plate 110 is 4.9mm-5.1mm, and / or, the spacing between two adjacent openings on the porous plate 110 is 11.4mm-11.6mm. Preferably, the diameter of each opening on the porous plate 110 is 5mm, and / or, the spacing between two adjacent openings on the porous plate 110 is 11.5mm, wherein "and / or" means that the diameter of each opening on the porous plate 110 and the spacing between two adjacent openings on the porous plate 110 are simultaneously or selectively set to the above-mentioned corresponding lengths respectively, and the two adjacent openings can be arranged side by side or staggered.

[0050] In this embodiment, in order to further enhance the noise reduction effect, for the structure between the porous plate 110 and the cover plate, the aforementioned third embodiment is preferably adopted, that is, a vibration-damping particle layer 131 and an airbag layer 132 filled with inert gas are simultaneously arranged between the porous plate 110 and the cover plate, and further, the vibration-damping particle layer 131 is arranged between the porous plate 110 and the airbag layer 132, and the airbag layer 132 is arranged between the vibration-damping particle layer 131 and the cover plate 120.

[0051] In this embodiment, the airbag layer 132 and the cover plate 120 are spaced apart from each other to form a first cavity 101 between the airbag layer 132 and the cover plate 120 . By providing the first cavity 101 , the air layer can be used to further consume the energy of the sound wave.

[0052] Preferably, the volume ratio of the air in the first cavity 101, the vibration-damping particles in the vibration-damping particle layer 131, and the airbags in the airbag layer 132 is 1:5:6 to 1.5:5:15, that is, in terms of volume, the first cavity 101 accounts for 7%-8%, the vibration-damping particle layer 131 accounts for 23%-42%, and the airbag layer 132 accounts for 50%-70%. Taking the installation of the noise reduction device provided in the preferred embodiment in the air duct volute of the range hood as an example, according to the noise spectrum test, the larger noise frequency range in the range hood is 200-1000HZ, of which the main peak parts are in the range of 200-220HZ, 800-900HZ, and 1000-1100HZ. Figure 2 As shown, in each order structure composed of the first cavity 101, the vibration-damping particle layer 131 and the airbag layer 132 of the present embodiment, there is its own resonant frequency. When the incident sound wave reaches the resonant frequency, the change of the sound pressure in the cavity will cause the air column to oscillate up and down, and most of the sound energy will be consumed by the viscous friction between the air in the cavity and the cavity surface, and in the gaps between adjacent vibration-damping particles. Furthermore, the combined structure of the first cavity 101, the vibration-damping particle layer 131 and the airbag layer 132 is similar to a multi-order resonant metasurface sound-absorbing structure, and an equivalent circuit diagram can be used to simulate the multi-order sound-absorbing structure. Specifically, refer to Figure 3 , after being simplified into an equivalent circuit diagram, it can be known that the equivalent acoustic impedance of the combined structure of the first cavity 101, the vibration-damping particle layer 131 and the airbag layer 132 is:

[0053] in:

[0054]

[0055]

[0056] Substituting the target frequency bands 200 Hz and 800 Hz into formula (a), we can obtain the corresponding volume ratio λ 1-2 =(u2 / u1)f i =1:5. Similarly, substituting the target frequency bands 800HZ and 1000HZ into formula (a), we can obtain the corresponding volume ratio λ 2-3 =(u3 / u2)f i=0.83:1, and combining the three can obtain that the corresponding volume ratio relationship of the air in the first cavity 101, the vibration-damping particles in the vibration-damping particle layer 131, and the airbags in the airbag layer 132 is 1:5:6, which can reduce the noise in the target frequency range of 200HZ, 800HZ, and 1000HZ; substituting the target frequency range of 220HZ, 900HZ, and 1100HZ in the same way, it can be obtained that the corresponding volume ratio relationship of the air in the first cavity 101, the vibration-damping particles in the vibration-damping particle layer 131, and the airbags in the airbag layer 132 is 1.5:5:15, which can reduce the noise in the target frequency range of 220HZ, 900HZ, and 1100HZ, so that the present embodiment can achieve the best noise reduction effect when installed on the volute of the air duct system of the range hood.

[0057] In this embodiment, the corresponding setting heights of the first cavity 101 , the vibration-damping particle layer 131 and the airbag layer 132 are not specifically limited, wherein the height refers to the distance in the direction extending from the porous plate 110 toward the cover plate 120 .

[0058] In this embodiment, there are many specific connection methods for the cover plate 120 to be connected to the porous plate 110, such as but not limited to: Figure 1 As shown, the edge of the porous plate 110 is integrally formed or welded or otherwise connected with a flange 111, and the cover plate 120 is connected to the flange 111. Specifically, the edge of the cover plate 120 can be connected to the flange 111 by, but not limited to, welding, clamping, bonding, screws or other connection methods, and the edge of the cover plate 120 can also be provided with an edge extending toward the porous plate 110, and the cover plate 120 is connected to the porous plate 110 through the edge.

[0059] Embodiment 2

[0060] This embodiment provides a volute, referring to Figure 4-Figure 7 The volute includes a volute body 1 and a noise reduction device provided by any optional embodiment in Example 1, wherein a porous plate 110 is installed on the outer wall of the volute body 1, and the porous plate 110 and the outer wall of the volute body 1 are spaced apart from each other to form a second cavity 102 between the outer wall of the volute body 1.

[0061] In this embodiment, there are many specific connection methods for the porous plate 110 to be connected to the volute body 1, such as but not limited to: Figure 4-Figure 7 As shown, the edge of the porous plate 110 is provided with a flange 111 extending toward the side of the porous plate 110, and the porous plate 110 is connected to the volute body 1 through the flange 111. Specifically, the flange 111 can be welded or clamped or connected to the volute body 1 by screws or other connection methods. Figure 1-Figure 7An extended edge 11 is provided at the edge of the air outlet of the volute body 1, and the porous plate 110 can be welded or clamped or connected to the extended edge 11 by screws or other connection methods; of course, the porous plate 110 can also be connected to the volute body 1 by further providing a surrounding plate, so that one end of the surrounding plate is connected to the volute body 1, and the other end is connected to the porous plate 110, etc., wherein it is more preferred that the edge of the above-mentioned porous plate 110 is provided with a flange 111 extending toward the side of the porous plate 110, and the porous plate 110 is connected to the volute body 1 by connecting the flange 111 to the volute body 1.

[0062] In this embodiment, the second cavity 102 formed between the porous plate 110 and the outer wall of the volute body 1 is combined with the openings on the porous plate 110 to form a structure similar to a Helmholtz resonator. This structure can form a resonant sound-absorbing structure with good effect, which can effectively absorb low-frequency noise, and then absorb the noise transmitted thereto together with the porous plate 110, and the absorbed noise frequency band is mainly low-frequency. The implementation of the structure of this embodiment has at least the following advantages: it can achieve a good sound absorption and noise reduction effect without changing the original internal structure of the air duct system, its structure is simple and easy to manufacture, cost-saving, and has good versatility, and the setting structure is mainly located outside the volute, and its noise reduction effect will not be affected by the oil pollution inside the air duct and is not easy to fail.

[0063] In addition, since the volute provided in this embodiment includes the noise reduction device described in Example 1, the volute provided in this embodiment can also achieve all the beneficial effects that the noise reduction device in Example 1 can achieve. For other specific structures and effects that can be achieved by the volute provided in this embodiment, reference can be made to the various optional or preferred embodiments in Example 1 and the embodiments described in combination with the reference. Figure 4-Figure 7 get.

[0064] Embodiment 3

[0065] This embodiment provides a range hood air duct system, which includes a volute provided by any optional implementation manner in the second embodiment.

[0066] Since the range hood air duct system provided in this embodiment includes the volute described in Example 2, the range hood air duct system provided in this embodiment can achieve all the beneficial effects that the volute in Example 2 can achieve, and its specific structure and achievable effects can be obtained by referring to Example 2.

[0067] Finally, it should be noted that: the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referenced to each other; the above embodiments in this specification are only used to illustrate the technical solution of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that: it is still possible to modify the technical solutions recorded in the aforementioned embodiments, or to replace some or all of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.

Claims

1. A volute, characterized in that: It comprises a volute body (1) and a noise reduction device, wherein: The noise reduction device comprises a porous plate (110) and a cover plate (120); A vibration-damping particle layer (131) and an air bag layer (132) filled with an inert gas are provided between the porous plate (110) and the cover plate (120); The vibration-damping particle layer (131) is arranged between the porous plate (110) and the airbag layer (132), and the airbag layer (132) is arranged between the vibration-damping particle layer (131) and the cover plate (120); the airbag layer (132) and the cover plate (120) are spaced apart from each other to form a first cavity (101) with the cover plate (120); the volume ratio of air in the first cavity (101), the vibration-damping particles in the vibration-damping particle layer (131), and the airbags in the airbag layer (132) is 1:5:6 to 1.5:5:15; The porous plate (110) is mounted on the outer wall of the volute body (1), and the porous plate (110) and the outer wall of the volute body (1) are spaced apart from each other to form a second cavity (102) between the porous plate (110) and the outer wall of the volute body (1).

2. The volute according to claim 1, characterized in that: The vibration-damping particles in the vibration-damping particle layer (131) are made of loose porous sound-absorbing material.

3. The volute according to claim 1, characterized in that: The vibration-damping particle layer (131) comprises at least two types of spherical particles with different diameters.

4. The volute according to claim 1, characterized in that: The diameter of each opening on the porous plate (110) is 4.9 mm to 5.1 mm, and / or the distance between two adjacent openings on the porous plate (110) is 11.4 mm to 11.6 mm.

5. The volute according to claim 1, characterized in that: The edge of the porous plate (110) is provided with a flange (111), and the cover plate (120) is connected to the flange (111).

6. A range hood air duct system, characterized in that: The invention comprises the volute as described in any one of claims 1 to 5.

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