Range hood with noise reduction function

Abstract

The utility model relates to a range hood with a noise reduction function. The range hood comprises a housing; the centrifugal fan is arranged in the machine shell and comprises a volute, an impeller arranged in the volute and a motor used for driving the impeller to rotate. A resonance silencing plate is arranged on the inner side wall of the machine shell, a plurality of resonance cavities are defined in the resonance silencing plate, sound inlets correspondingly communicated with the resonance cavities are defined in the side wall of the side, facing the interior of the machine shell, of the resonance silencing plate, and first sound absorption pieces are arranged in the resonance cavities. The side wall of the side, facing the interior of the machine shell, of the resonance silencing plate is provided with a second sound absorption piece, the second sound absorption piece covers all sound inlets in the resonance silencing plate, and at least part of the side wall of the volute is of a noise reduction plate body structure made of a PET long fiber thermoplastic composite material. The range hood has the advantage that the noise problem of the whole wide frequency band of the range hood can be effectively solved.

Description

Technical Field

[0001] The utility model relates to the technical field of range hoods, in particular to a range hood with a noise reduction function. Background Art

[0002] Range hoods are kitchen appliances that purify the kitchen environment. With people's pursuit of healthy life, in addition to paying attention to the effect of range hoods in absorbing and exhausting oil fumes, people are paying more and more attention to the impact of range hood noise. The noise reduction of range hoods is mainly passive noise reduction, among which the three passive noise reduction methods of sound absorption, sound elimination and sound insulation are the most widely used. Traditional sound insulation and sound-absorbing materials generally include wool felt, polyester fiber, foaming material, bi-component fiber, etc., but the existing conventional sound-absorbing materials, especially polyurethane, fiber and other materials, need to have a certain thickness to reflect a good sound absorption effect, and usually, the sound absorption coefficient at 200-500Hz is also relatively low, and the main frequency band of range hoods is 100-2000Hz, so the noise reduction effect of the whole range hood is a bit less than ideal. For example, the Chinese invention patent application with application number 201310627547.X discloses a silent range hood with a sound-absorbing cover, which includes a microporous cavity and sound-absorbing cotton filled in the cavity. The perforated plate absorbs intermediate frequencies by utilizing the resistive noise reduction principle of sound absorption by resonance. The sound-absorbing cotton is a porous sound-absorbing material with resistive noise reduction, which mainly absorbs medium and high frequency sound waves. However, after being in an oil fume environment for a period of time, the ventilation holes of the porous sound-absorbing material will be blocked to form closed holes, thereby losing the noise reduction function.

[0003] In summary, existing range hood products mostly use some structural noise reduction or sound-absorbing material layout to reduce noise, but this traditional noise reduction method does not solve the noise problem of the entire wide frequency band of the range hood, and does not effectively reduce noise from the noise source and in the propagation path, so the noise reduction effect is limited. Therefore, the existing range hoods need further improvement. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a range hood which can effectively improve the noise problem of the whole wide frequency band of the range hood in view of the current status of the prior art.

[0005] The technical solution adopted by the utility model to solve the above technical problems is: a range hood with noise reduction function, comprising:

[0006] chassis;

[0007] A centrifugal fan is arranged in the casing, comprising a volute, an impeller arranged in the volute, and a motor for driving the impeller to rotate;

[0008] A resonance sound-absorbing plate is provided on the inner side wall of the casing, a plurality of resonance chambers are defined on the resonance sound-absorbing plate, and a sound inlet corresponding to each resonance chamber is defined on a side wall facing the inside of the casing, each resonance chamber is provided with a first sound-absorbing member, a side wall of the resonance sound-absorbing plate facing the inside of the casing is provided with a second sound-absorbing member, the second sound-absorbing member covers each sound inlet on the resonance sound-absorbing plate, and at least part of the side wall of the volute is a noise reduction plate structure made of PET long-fiber thermoplastic composite material.

[0009] In order to improve the overall noise reduction effect, the first sound absorbing member is a single-component sound absorbing member, and the second sound absorbing member is a multi-component sound absorbing member. The second sound absorbing member adopts a multi-component sound absorbing member, such as a multi-component sound absorbing cotton, which can effectively absorb high-frequency noise. The first sound absorbing member, which is mainly a single-component sound absorbing member, is arranged in the resonance chamber, so that the incident sound entering the resonance chamber and part of the reflected sound can be directly absorbed again, thereby improving the sound absorption effect.

[0010] In order to further improve the sound absorption effect, the first sound absorbing member in each of the resonance chambers is opposite to the corresponding sound inlet on the resonance sound-absorbing plate.

[0011] As an improvement, each sound inlet on the resonant sound-absorbing plate is in the shape of an elongated strip, and the first sound-absorbing member in each resonant chamber is also in the shape of a corresponding elongated strip.

[0012] In order to facilitate the installation of the first sound absorbing member and simplify the structure of the resonance sound-absorbing plate, the resonance sound-absorbing plate includes a first plate body and a second plate body arranged side by side at intervals, the first plate body is used to be placed on the inner wall of the casing, and the second plate body has partitions on one side wall facing the first plate body, which are arranged in sequence at intervals in its extension direction and all extend toward the first plate body, each of the partitions is connected to the first plate body, and the two adjacent partitions and the corresponding parts of the first plate body and the second plate body define the resonance chamber, and the sound inlet is opened on the main body of the second plate body corresponding to the area between the two adjacent partitions.

[0013] To facilitate the placement of the first sound absorbing member, a first mounting groove for mounting the first sound absorbing member is provided on the side wall of the first plate body facing the second plate body, corresponding to the area between two adjacent partitions. It is conceivable that the first sound absorbing member can also be fixed to the side wall of the first plate body by bonding or other methods.

[0014] In order to form the above-mentioned first installation groove, the first installation groove on the first plate body is surrounded by a first annular stopper extending from the side wall of the first plate body toward the second plate body.

[0015] In order to facilitate the installation of the second sound absorbing member, the outer peripheral edge of the second plate body away from the first plate body has a second annular retaining edge extending toward the second plate body, and the second annular retaining edge is surrounded to form a second installation groove for installing the second sound absorbing member. It is conceivable that the second sound absorbing member can also be fixed to the side wall of the second plate body by bonding or other methods.

[0016] In order to improve the noise reduction effect at the noise source, the side wall of the volute is a noise reduction plate structure made of PET long-fiber thermoplastic composite material as a whole.

[0017] Since the position of the casing opposite to the volute air inlet is the main path for noise propagation, in order to further improve the noise reduction effect, the volute is provided with an air inlet, and the casing is provided with the resonance silencer plate on at least one side wall facing the volute air inlet.

[0018] Compared with the prior art, the utility model has the following advantages: the volute in the utility model adopts PET long fiber thermoplastic composite material to replace the conventional metal volute structure. Since the composite material has a large number of microporous gaps, it has good sound absorption and noise reduction functions, and can greatly reduce the resonant low-frequency noise caused by the metal volute. While reducing the low-frequency vibration sound, the sound energy can also be reduced through the sound absorption characteristics of the material, achieving the purpose of noise reduction and sound absorption at the source of the noise. On this basis, a resonant muffler plate is designed on the inner wall of the casing, and a first sound absorbing member is set in the resonant chamber in the resonant muffler plate, and a second sound absorbing member is set at the sound entrance of the resonant muffler plate, so that the resonant chamber has both sound absorbing member adsorption and resonance consumption of noise energy. The high-frequency, medium-frequency and low-frequency noises are targetedly reduced through graded sound absorption and sound insulation, effectively improving the noise problem of the entire wide frequency band of the range hood. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional structural schematic diagram of a range hood according to an embodiment of the utility model;

[0020] Figure 2 A vertical cross-sectional view of the range hood according to an embodiment of the utility model cut along the front-to-back direction;

[0021] Figure 3 It is a schematic diagram of the three-dimensional structure of the resonance sound-absorbing plate of an embodiment of the utility model;

[0022] Figure 4 A cross-sectional perspective view of a resonance muffler plate according to an embodiment of the utility model;

[0023] Figure 5 This is an exploded view of the resonant sound-absorbing plate in a cut-away state according to an embodiment of the utility model. DETAILED DESCRIPTION

[0024] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0025] In the specification and claims of the present invention, terms indicating directions, such as "front", "rear", "up", "down", "left", "right", "side", "top", "bottom", etc., are used to describe various exemplary structural parts and elements of the present invention, but these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only used as explanations and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

[0026] Figure 1-Figure 5 A preferred embodiment of the range hood with noise reduction function of the utility model is shown. The range hood includes a casing 10 and a centrifugal fan 2 arranged in the casing 10. The casing 10 generally includes a fan frame 11 and a smoke hood 12 arranged at the bottom of the fan frame 11. The inner cavity of the fan frame 11 is connected with the inner cavity of the smoke hood 12. An air suction port (not shown) is provided on the front side wall of the smoke hood 12, and external smoke can enter the smoke hood 12 through the air suction port. The centrifugal fan 2 is arranged in the fan frame 11. When the centrifugal fan 2 is in operation, negative pressure is generated to suck oil smoke. An oil net is also provided at the air suction port of the smoke hood 12 to filter oil smoke. An oil cup 13 is provided at the bottom of the smoke hood 12 to collect oil stains flowing down from the smoke hood 12.

[0027] In order to effectively reduce noise at the source of noise, at least part of the side wall of the volute 21 of the centrifugal fan 2 of this embodiment is a noise reduction plate structure made of PET long fiber thermoplastic composite material. Preferably, the side wall of the volute 21 is a noise reduction plate structure made of PET long fiber thermoplastic composite material as a whole. The volute 21 made of PET long fiber thermoplastic composite material is used to replace the ordinary metal volute 21, which can reduce noise and absorb sound at the source of noise. It has a large number of microporous gaps and good sound absorption and noise reduction functions. The material has extremely low water absorption, high temperature resistance, combustion resistance, excellent mechanical properties, tear resistance and impact resistance.

[0028] In order to effectively reduce high-frequency, medium-frequency and low-frequency noise in the noise propagation path, a resonance sound-absorbing plate 3 is provided on the inner side wall of the housing 10, and a plurality of resonance chambers 30 are defined on the resonance sound-absorbing plate 3, and a sound inlet 301 corresponding to each resonance chamber 30 is defined on the side wall facing the inside of the housing 10. A first sound-absorbing member 33 is provided in each resonance chamber 30, wherein the first sound-absorbing member 33 can be a single-component sound-absorbing member, such as a single-component sound-absorbing cotton. A second sound-absorbing member 34 is provided on the side wall of the resonance sound-absorbing plate 3 facing the inside of the housing 10, and the second sound-absorbing member 34 is a multi-component sound-absorbing member, such as a multi-component sound-absorbing cotton, for absorbing high-frequency noise. The second sound-absorbing member 34 covers each sound inlet 301 on the resonance sound-absorbing plate 3.

[0029] The resonance sound-absorbing plate 3 includes a first plate body 31 and a second plate body 32 arranged side by side and spaced apart. The first plate body 31 can be fixed on the inner side wall of the housing 10, and the second plate body 32 is closer to the inside of the housing 10 than the first plate body 31. A side wall of the second plate body 32 facing the first plate body 31 has a plurality of partitions extending toward the first plate body 31. A plurality of shelves 321 are sequentially arranged at intervals along the extension direction of the second plate body 32 and connected to the first plate body 31, thereby, two adjacent partitions and corresponding parts of the first plate body 31 and the second plate body 32 define a resonance chamber 30, wherein the sound inlet 301 is opened on the main body of the second plate body corresponding to the area between the two adjacent partitions. A first mounting groove 3110 is provided on the side wall of the first plate body 31 facing the second plate body corresponding to the area between the two adjacent partitions, and the first sound absorbing member 33 can be embedded and installed in the first mounting groove 3110. Specifically, the first mounting groove 3110 on the first plate 31 is formed by a first annular retaining edge 311 extending from the side wall of the first plate 31 toward the second plate. It is conceivable that the first sound absorbing member 33 can also be fixed to the side wall of the first plate 31 by bonding or other methods.

[0030] The resonance chamber 30 is in the shape of a long strip as a whole, and the sound inlet 301 corresponding to each resonance chamber 30 is in the shape of a long strip, wherein the first sound absorbing member 33 in the resonance chamber 30 is also in the shape of a corresponding long strip. The first sound absorbing member 33 installed in the resonance chamber 30 is opposite to the corresponding sound inlet 301 on the second plate 32.

[0031] The second plate body 32 has a second annular retaining edge 322 extending toward the second plate body at the outer peripheral edge of one side away from the first plate body 31, and the second annular retaining edge 322 surrounds and forms a second installation groove 3220 for installing the second sound absorbing member 34. Specifically, the second sound absorbing member 34 can be embedded and installed in the second installation groove 3220 and cover each sound inlet 301 on the second plate body 32. It is conceivable that the second sound absorbing member 34 can also be fixed to the side wall of the second plate body by bonding or other methods.

[0032] Since the position of the casing 10 facing the air inlet 210 of the volute 21 is the main path for noise propagation, in order to further improve the noise reduction effect, the front and rear cover plates of the volute 21 are provided with air inlets 210, and the casing 10 is provided with the above-mentioned resonance muffler plate 3 on at least one side wall facing the air inlet 210 of the volute 21. Figure 2 As shown, resonance muffler plates 3 are provided on the front and rear side walls of the fan frame 11 .

[0033] The volute 21 of the centrifugal fan 2 of this embodiment is made of PET long-fiber thermoplastic composite material, which can effectively reduce some low-frequency resonance frequencies below 500Hz. In addition, it can also absorb the main distribution frequency of the range hood noise of 500-2000Hz, thereby reducing the overall energy of the noise. After the noise that is not absorbed by the volute 21 is transmitted through the volute 21, it faces the two-component material (i.e., the second sound-absorbing member 34) on the resonance noise reduction plate, so that most of the medium and high frequency noise is directly absorbed by the two-component material, and the noise that is not completely absorbed will enter the Helmholtz resonance chamber 30 through the gap. A single-component sound-absorbing member (i.e., the first sound-absorbing member 33) is placed in the Helmholtz resonance chamber 30 facing the sound inlet 301, so that the incident sound and part of the reflected sound can be directly absorbed again. In addition, the Helmholtz resonance chamber 30 is basically divided into two rectangular spaces on the left and right by a single-component material. When noise enters this position, it will be reflected back and forth repeatedly. When the sound wave propagates to the surface of the inner cavity, part of the sound wave will be reflected back and then absorbed by the double-component material above, and the other part will be directly absorbed by the single-component sound-absorbing material and converted into mechanical energy transmission or heat energy consumption. Another part will be refracted into two small inner cavities. In the small inner cavity, because the sound energy vibrates back and forth in a relatively closed cavity, the air in the cavity moves back and forth and is compressed, forming an air spring, so that the noise energy can be consumed to a greater extent, thereby making the noise lower. When the frequency of the incident sound wave is consistent with the natural frequency of the resonance chamber 30 structure, the resonance amplitude is the largest and the energy consumed is the most. The resonant sound-absorbing structure of the resonant chamber 30 is highly selective with respect to the sound-absorbing frequency, and the sound-absorbing effect is generally better at medium and low frequencies, so there is no noise absorbed by the two-component material. The specific frequency band can be determined by testing the spectrum, and then by adjusting the size of the Helmholtz resonant cavity (such as the opening size and the inner cavity size), different frequencies can be processed separately.

Claims

1. A range hood with noise reduction function, comprising: Housing (10); A centrifugal fan (2) is arranged in the casing (10), comprising a volute (21), an impeller (22) arranged in the volute (21), and a motor (23) for driving the impeller (22) to rotate; The invention is characterized in that: a resonance sound-absorbing plate (3) is provided on the inner side wall of the housing (10), a plurality of resonance chambers (30) are defined on the resonance sound-absorbing plate (3), and a sound inlet (301) corresponding to and connected to each resonance chamber (30) is defined on a side wall facing the inside of the housing (10), each resonance chamber (30) is provided with a first sound-absorbing member (33), a side wall of the resonance sound-absorbing plate (3) facing the inside of the housing (10) is provided with a second sound-absorbing member (34), and the second sound-absorbing member (34) covers each sound inlet (301) on the resonance sound-absorbing plate (3), and at least part of the side wall of the volute (21) is a noise-reducing plate structure made of PET long-fiber thermoplastic composite material.

2. The range hood with noise reduction function according to claim 1, characterized in that: The first sound absorbing member (33) is a single-component sound absorbing member, and the second sound absorbing member (34) is a multi-component sound absorbing member.

3. The range hood with noise reduction function according to claim 1, characterized in that: The first sound absorbing member (33) in each of the resonance chambers (30) is opposite to the corresponding sound inlet (301) on the resonance sound-absorbing plate (3).

4. The range hood with noise reduction function according to claim 2, characterized in that: Each sound inlet (301) on the resonance sound-absorbing plate (3) is in the shape of an elongated strip, and the first sound-absorbing member (33) in each resonance chamber (30) is also in the shape of a corresponding elongated strip.

5. The range hood with noise reduction function according to claim 1, characterized in that: The resonant sound-absorbing plate (3) comprises a first plate body (31) and a second plate body (32) arranged side by side at intervals, wherein the first plate body (31) is used to be placed on the inner side wall of the housing (10), and the second plate body (32) has partitions arranged in sequence at intervals in its extension direction and extending toward the first plate body (31) on a side wall facing the first plate body (31), each of the partitions is connected to the first plate body (31), and two adjacent partitions and corresponding parts of the first plate body (31) and the second plate body (32) define the resonant chamber (30), and the sound inlet (301) is opened on the main body of the second plate body corresponding to the area located between the two adjacent partitions.

6. The range hood with noise reduction function according to claim 5, characterized in that: A first mounting groove (3110) for mounting the first sound absorbing member (33) is provided on the side wall of the first plate body (31) facing the second plate body in an area corresponding to the area between two adjacent partitions.

7. The range hood with noise reduction function according to claim 6, characterized in that: The first installation groove (3110) on the first plate body (31) is formed by being surrounded by a first annular retaining edge (311) extending from the side wall of the first plate body (31) toward the second plate body.

8. The range hood with noise reduction function according to claim 5, characterized in that: The second plate body (32) has a second annular retaining edge (322) extending toward the second plate body at the outer peripheral edge of the side away from the first plate body (31), and the second annular retaining edge (322) is surrounded to form a second installation groove (3220) for installing the second sound absorbing member (34).

9. The range hood with noise reduction function according to claim 1, characterized in that: The side wall of the volute (21) is entirely a noise reduction plate structure made of PET long-fiber thermoplastic composite material.

10. The range hood with noise reduction function according to any one of claims 1 to 9, characterized in that: The volute (21) is provided with an air inlet (210), and the housing (10) is provided with the resonant sound-absorbing plate (3) on at least one side wall facing the air inlet (210) of the volute (21).

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