A range hood

Abstract

The utility model discloses a kind of range hood, including smoke inlet, fan and for being set between the smoke inlet and fan of range hood air inlet passage;The air inlet passage includes box and the air duct in box, the air duct has as the first port of air inlet and as the second port of noise sound wave entrance, the first port is located below second port;The wall surface of the air duct includes two wall surfaces spaced apart along the front-back direction of range hood, at least partially protrudes forward in the wall surface of rear side.

Description

Technical Field

[0001] This utility model relates to an oil fume purification device, and more particularly to an oil fume extractor. Background Technology

[0002] As living standards continue to improve, consumers' demands for home appliances have shifted from simple functional needs to diversified quality requirements. Taking range hoods as an example, while ensuring efficient smoke extraction, they also need to operate with low noise. Quiet performance has become one of the core indicators for consumers to evaluate the quality of home appliances, directly affecting the product's market competitiveness and user experience.

[0003] Existing range hoods with airflow guiding and noise reduction functions, such as the airflow guiding structure and range hood disclosed in Chinese Patent Application No. 202321875584.8, include a curved airflow guide and an additional oil guide groove. The curved airflow guide is located at the junction of the high-speed airflow area and the low-speed airflow area in the smoke collection chamber. The curved airflow guide can eliminate airflow vortices inside the smoke collection chamber, improve airflow uniformity, and reduce the noise of the range hood. The curved airflow guide has a highest point on the curved surface, through which the first oil can drip into the oil cup, thereby efficiently guiding most of the oil stains into the oil cup and preventing oil stains from dripping from the smoke inlet onto the countertop. The additional oil guide groove is located on the curved airflow guide and below the highest point of the curved surface. The second oil located below the highest point of the curved surface can drip into the oil cup through the additional oil guide groove, thereby smoothly guiding the remaining oil stains into the oil cup and further preventing oil stains from dripping from the smoke inlet onto the countertop, further improving the user experience.

[0004] However, since range hoods typically place the oil cup at the bottom rear of the air inlet (smoke collection chamber), in order for the oil to drip into the oil cup without dripping through the smoke inlet, the highest point of the curved guide surface must be as close to the rear as possible. This causes the oil smoke flow channel between the guide surface and the rear wall of the air inlet to be compressed, resulting in increased resistance to the upward flow of oil smoke and affecting the smoke extraction effect. Adding an additional oil guiding component would complicate the structure and increase the cost. Utility Model Content

[0005] The technical problem to be solved by this utility model is to address the shortcomings of the existing technology by providing a range hood that, with a simple structure, can achieve a flow channel with low resistance and facilitate the collection of oil.

[0006] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: a range hood with an air inlet channel, comprising a smoke inlet, a fan, and an air inlet channel disposed between the smoke inlet and the fan; the air inlet channel includes a housing and a duct located within the housing, the duct having a first port as an airflow inlet and a second port as a noise sound wave inlet, the first port being located below the second port; characterized in that:

[0007] The duct wall includes two walls spaced apart along the front-to-back direction of the range hood, with the rear wall at least partially protruding forward.

[0008] By making the rear sidewall of the duct bulge forward, the airflow of cooking fumes is guided to flow smoothly, reducing resistance and turbulence, and without excessively compressing the duct. This ensures sufficient air intake area so that the cooking fumes can flow upward quickly. In addition, the bulging rear sidewall of the duct can be easily designed to prevent oil droplets from dripping into the smoke inlet. At the same time, oil on the entire bulging wall surface can flow downward along the rear sidewall and be collected without the need for additional oil guiding components. This simplifies the structure and avoids increasing resistance by placing too many components in the duct.

[0009] Preferably, each wall is made of panels, which facilitates the formation of air ducts with the enclosure and also makes installation easier.

[0010] Preferably, in order to form a relatively enclosed air duct, the two side walls and plates of the housing along the width direction of the range hood together form the air duct.

[0011] According to one aspect of the present invention, each wall surface is composed of an integrally formed plate.

[0012] To facilitate stable installation of the upper part of the plate, the plate part connected to the second port is provided with a first flange on both sides of the plate that connects to the housing along the width direction of the range hood. The first flange extends along the front-to-back direction of the range hood.

[0013] To facilitate stable installation of the upper part of the plate, the housing has a first opening corresponding to the first port and a second opening corresponding to the second port. The top of the plate connected to the second port is provided with a second flange, which is connected to the edge of the second opening.

[0014] To facilitate installation and transportation and avoid excessive length of individual panels, the panel connected to the first port is composed of at least two sub-panels arranged vertically and joined together.

[0015] Furthermore, the plate portion connected to the first port includes a first sub-plate connected to the first port and a second sub-plate disposed on the first sub-plate. The projection of the lower boundary of the second sub-plate on the horizontal plane is located on the side away from the air duct from the projection of the upper boundary of the first sub-plate on the horizontal plane. Thus, the first sub-plate can receive the oil flowing down from the second sub-plate and prevent it from dripping directly downwards.

[0016] To facilitate stable installation of the lower part of the panel, the second sub-panel has a third flange on both sides along the width direction of the range hood, which is connected to the housing. The third flange extends along the front-to-back direction of the range hood.

[0017] To prevent oil fumes from encountering abrupt changes in the flow path, the first sub-plate includes a first portion that extends in the same direction as the second sub-plate.

[0018] Furthermore, the first sub-plate also includes a second portion extending from the upper end of the first portion in a direction away from the air duct. The end of the second portion away from the first portion forms a fourth flange that connects to the housing, and the fourth flange extends downward. The arrangement of the second portion facilitates the installation of the first sub-plate and guides the oil flowing down from the second sub-plate toward the wall of the housing, and then further downward.

[0019] Furthermore, the wall surface constituting the air duct includes at least:

[0020] A sound-facing surface, which faces the direction of sound wave input and impacts the sound wave, wherein the sound-facing surface is a wall surface that allows noise to pass through; and

[0021] The frontal surface faces the direction of airflow input and impacts the airflow.

[0022] One of the plates has at least an acoustic surface and the other plate has at least an airflow surface.

[0023] By utilizing the characteristic that airflow and sound waves propagate in opposite directions, the air duct wall of the range hood's air intake channel is divided into two different functional surfaces: the sound-facing surface and the airflow-facing surface. This approach can balance both noise reduction and airflow performance, improving noise reduction while also enhancing airflow efficiency.

[0024] Preferably, to facilitate the escape of noise from the duct and reduce its propagation to the first port, at least some of the plates on the front and rear sides of the duct are perforated.

[0025] Preferably, the opening ratio of the plates on both sides of the air duct is 5% to 50%.

[0026] Preferably, in order to facilitate the noise to pass out of the air duct and reduce the propagation to the first port, the plates on the front and rear sides of the air duct are opened as a whole or at least opened on the sound-facing side.

[0027] Preferably, according to one aspect of the present invention, the plates on both the front and rear sides of the air duct are uniformly perforated.

[0028] Preferably, in order to achieve better noise reduction effect, the diameter of the holes on the plate is 1 to 10 mm, and the spacing between adjacent holes is 5 to 20 mm.

[0029] Preferably, according to another aspect of the present invention, the plates on both sides of the air duct are integrally perforated, and the perforation ratio near the second port is greater than that near the first port. Thus, when noise enters the air duct from the second port, it can smoothly exit the air duct due to the larger perforation ratio, while at the first port, the smaller perforation ratio prevents the noise from re-entering the air duct.

[0030] Preferably, in order to ensure that both the front and rear walls of the duct can guide the fumes and absorb noise, the acoustic surface includes a first acoustic surface connected to the second port and a second acoustic surface connected to the first port, and the airflow surface includes a first airflow surface connected to the first port and a second airflow surface connected to the second port; along the front-rear direction of the range hood, the first acoustic surface and the first airflow surface are located on the same side of the duct, and the second acoustic surface and the second airflow surface are located on the same side of the duct.

[0031] Furthermore, the first acoustic surface and the second airflow surface, as well as the first airflow surface and the second acoustic surface, are respectively connected by curved surfaces, which are closed walls. This smoothly guides the airflow at the junction of the two functional walls (usually at the wall turning point), avoiding turbulence caused by abrupt changes in the path.

[0032] Preferably, to maintain good airflow performance, on the vertical cross-section extending along the front-back direction of the range hood, the top of the rear wall of the duct has the rearmost first rear point, the bottom of the rear wall of the duct has the rearmost second rear point, the line connecting the frontmost first vertex and the first rear point corresponding to the protruding part of the rear wall of the duct is the first connecting line, the line connecting the first vertex and the second rear point is the second connecting line, the included angle between the first connecting line and the second connecting line is α, and satisfies 90°<α≤150°.

[0033] Preferably, on the vertical cross section extending along the front-back direction of the range hood, the bottom of the rear wall of the duct has the rearmost second rear point, and the angle between the line connecting the frontmost first vertex and the second rear point corresponding to the protruding part of the rear wall of the duct and the horizontal plane is γ, and satisfies 60°≤γ≤90°, thereby facilitating the downward guidance of oil on the rear wall.

[0034] Preferably, the front wall of the air duct is a vertical wall or a wall that protrudes forward.

[0035] Preferably, to maintain good airflow performance, the front wall of the duct is a forward-convex wall. On a vertical cross-section extending along the front-rear direction of the range hood, the top of the front wall of the duct has the rearmost third rear point, and the bottom of the front wall of the duct has the rearmost fourth rear point. The line connecting the frontmost second vertex and the third rear point corresponding to the protruding part of the front wall of the duct is the third line, and the line connecting the second vertex and the fourth rear point is the fourth line. The included angle between the third line and the fourth line is β, and satisfies 120°≤β≤150°.

[0036] Compared with the prior art, the advantages of this utility model are as follows: by making the rear sidewall of the air duct protrude forward, the oil fume airflow is guided to flow smoothly, reducing resistance and eddies, and without excessively compressing the air duct, ensuring sufficient air intake area so that the oil fume can flow upward quickly. In addition, the protrusion of the rear sidewall of the air duct can be easily designed to prevent oil droplets on it from entering the smoke inlet. At the same time, the oil on the entire protruding wall surface can flow downward along the rear sidewall and be collected without the need for additional oil guiding components, simplifying the structure and avoiding the increase in resistance caused by setting too many components in the air duct. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a range hood according to an embodiment of the present utility model;

[0038] Figure 2 This is a cross-sectional view of the range hood according to an embodiment of the present utility model;

[0039] Figure 3 This is a cross-sectional view of the range hood according to an embodiment of the present invention (and...). Figure 2 (Different perspectives);

[0040] Figure 4 This is a cross-sectional side view of the air inlet channel of the range hood according to an embodiment of the present utility model;

[0041] Figure 5 This is an exploded structural diagram of the air inlet channel of the range hood according to an embodiment of the present utility model;

[0042] Figure 6 This is a side view of the duct wall of the range hood according to an embodiment of the present invention. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0044] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Since the embodiments disclosed in this utility model can be arranged in different directions, these terms indicating direction are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0045] See Figures 1-6 A range hood includes a fan 200, an air inlet 300, and an air inlet channel 100 disposed between the fan 200 and the air inlet 300. When the range hood is turned on, the fan 200 starts and draws in cooking fumes through the smoke inlet (not labeled, existing technology) at the air inlet 300, and then exhausts them through the fan 200.

[0046] In this embodiment, the range hood can be a ceiling-mounted type, meaning its fan 200 is placed above the kitchen ceiling. The fan 200 is horizontally arranged, meaning it has a downward-facing air inlet 201, and there is sufficient space between the air inlet body 300 and the fan 200 to accommodate the air inlet channel 100. Of course, in other types of range hoods, the air inlet channel 100 of appropriate size can be selected according to the actual space.

[0047] The air inlet channel 100 includes a housing 1 and an air duct Q disposed within the housing 1. The air duct Q has a first port 21 and a second port 22. The first port 21 serves as both a fluid inlet and a noise outlet, while the second port 22 serves as both a fluid outlet and a noise inlet. The housing 1 has openings at positions corresponding to the first port 21 and the second port 22. In this embodiment, the first port 21 is located at the bottom of the air duct Q, and the second port 22 is located at the top of the air duct Q. The housing 1 has a first opening 11 corresponding to the first port 21, and a second opening 12 corresponding to the second port 22, to facilitate the flow of fumes. The direction in which the air duct Q extends between the first port 21 and the second port 22 is the length direction (Z-axis direction) of the air duct Q. The first port 21 and the second port 22 are arranged at intervals along the Z-axis direction. Here, "interval arrangement" does not strictly require that the first port 21 and the second port 22 be aligned in the X-axis direction (described in detail below); they can be arranged as follows: Figure 4 The diagram shows an aligned arrangement, but a staggered arrangement is also possible. The width direction of the air duct Q is... Figure 4 The X-axis direction shown is the depth direction of the air duct Q. Figure 4 As shown in the Y-axis direction, the depth direction of the air duct Q is also the width direction of the entire range hood.

[0048] In this embodiment, the width direction of the air duct Q is the front-to-back direction of the range hood, which makes it particularly suitable for the air inlet 300 in this embodiment. Due to the ultra-thin shape limitation of the air inlet 300 in this embodiment, the air duct Q is matched with it to form a long and narrow shape along the left-to-right direction of the range hood. Along the X-axis direction, the rear side wall of the air duct Q protrudes forward at least partially, and the front side wall of the air duct Q is a vertical wall or a wall that protrudes forward. In this embodiment, both the rear side wall and the front side wall protrude forward as a whole.

[0049] The rear and front walls of the duct Q may each include one or at least two curved or flat surfaces connected end to end. In the cross-section of the planes along the length and width of the duct Q, in this embodiment, the vertical plane S (the plane containing the X and Z axes) extending along the front-rear direction of the range hood... Figures 2-4 The cross section and Figure 1 The vertical planes S shown in the diagram coincide or are parallel, with wavy or sawtooth inner surfaces. The curvature of adjacent surfaces can be the same or different. The number of surfaces or planes can also be selected as needed. This forms a non-linear air duct, which helps reduce noise.

[0050] In the air ducts of household appliances, the fluid (usually airflow) and sound waves propagate in opposite directions. When a range hood is working, cooking fumes are drawn upwards, while the noise from the fan 200 propagates downwards. Therefore, based on this characteristic of airflow and sound wave propagation in opposite directions, this invention divides the inner surfaces of each panel into two different functional areas: the sound-facing surface and the airflow-facing surface. The sound-facing surface is the main surface on which sound waves directly incident, aligned with the direction of sound wave propagation. It allows noise waves to pass through, and the airflow does not directly impact this area during its propagation. The airflow-facing surface, on the other hand, is the main surface on which the airflow directly impacts, aligned with the direction of airflow propagation. The airflow-facing surfaces on opposite sides along the X-axis have at least one sound-facing surface and at least one airflow-facing surface, with the sound-facing surface on one side facing the airflow-facing surface on the other.

[0051] In this embodiment, the rear wall of the duct Q is divided into a first acoustic surface 251 and a first airflow surface 241. The first airflow surface 241 is located below the first acoustic surface 251 and is connected to the first port 21. The first acoustic surface 251 is connected to the second port 22. The first acoustic surface 251 extends forward from top to bottom, and the first airflow surface 241 extends forward from bottom to top. The front wall of the duct Q is divided into a second acoustic surface 252 and a second airflow surface 242. The second acoustic surface 252 is located below the second airflow surface 242 and is connected to the first port 21. The second airflow surface 242 is connected to the second port 22. The second acoustic surface 252 extends forward from bottom to top, and the second airflow surface 242 extends forward from bottom to top. The transition between the first acoustic surface 251 and the first airflow surface 241, and between the second airflow surface 242 and the second acoustic surface 252, is preferably achieved through a curved surface 253. This curved surface 253 is a closed wall surface that smoothly guides the airflow at the junction of the two functional walls (usually at the wall turning point), avoiding turbulence caused by abrupt path changes. Therefore, in this embodiment, both the rear and front walls of the air duct Q have a forward-convex shape.

[0052] On a vertical cross-section extending along the front-to-back direction of the range hood (this cross-section is...) Figure 1 The cross section S shown, or the plane parallel to cross section S, in this embodiment... Figure 6 The side view is used instead of the cross-sectional view of the two walls of the air duct (the angles, endpoints, etc. are the same as in the cross-section). The top of the rear wall of the air duct Q has the rearmost first rear point M1, and the bottom of the rear wall of the air duct has the rearmost second rear point M2. The line connecting the first vertex N1 and the first rear point M1 corresponding to the protruding part of the rear wall of the air duct (the curved surface 253 on the rear side) is the first connecting line L1. The line connecting the first vertex N1 and the second rear point M2 is the second connecting line L2. The included angle between the first connecting line L1 and the second connecting line L2 is α, and satisfies 90°<α≤150°. The included angle between the second connecting line L2 and the horizontal plane is γ, and satisfies 60°≤γ≤90°.

[0053] On a vertical cross-section extending along the front-to-back direction of the range hood (in this embodiment, ) Figure 6 The side view is shown below (the angles, endpoints, etc. are the same as those on the cross section). The top of the front wall of the air duct Q has the rearmost third rear point M3, and the bottom of the front wall of the air duct Q has the rearmost fourth rear point M4. The line connecting the second vertex N2 and the third rear point M3 corresponding to the protruding part of the front wall of the air duct Q (the curved surface 253 on the rear side) is the third connecting line L3, and the line connecting the second vertex N2 and the fourth rear point M4 is the fourth connecting line L4. The included angle between the third connecting line L3 and the fourth connecting line L4 is β, and satisfies 120°≤β≤150°.

[0054] The walls of the air duct Q, spaced apart along the X-axis, can be constructed from individual plates 23. Each plate 23 extends along the Y-axis to the corresponding wall of the housing 1. Thus, the two side walls of the housing 1 along the Y-axis (i.e., the width of the entire range hood) and the two plates together form the air duct Q. Each plate 23 can be a single piece or composed of at least two vertically arranged sub-plates joined together. Here, "joined together" does not necessarily imply a mechanical connection. By using plates 23, the air duct Q can be easily constructed, and it is also convenient to install it in conjunction with the housing 1.

[0055] To facilitate stable installation of the upper part of plate 23, the portion of plate 23 connected to the second port 22 (the portion corresponding to the first acoustic surface 251 and the second airflow surface 242) has first flanges 233 on both sides along the width direction of the range hood, which connect to the housing 1. The first flanges 233 extend along the front-to-back direction of the range hood. The top of plate 23 connected to the second port 22 has a second flange 234, which extends vertically and connects to the second opening 12 of the housing 1. Figure 5 As shown, the box body 1 includes a box body 13 and a top plate 14 disposed on the top of the box body 13. A second opening 12 is disposed on the top plate 14, and a fifth flange 141 connected to the second flange 234 is formed along the edge of the second opening 12 on the top plate 14.

[0056] As mentioned above, each panel 23 involves multiple panels joined together. Therefore, there is a possibility of incompletely continuous transitions between adjacent acoustic and airflow-facing surfaces, or discontinuous extensions within the same surface. The "end-to-end connection" described above does not necessarily mean a smooth transition; misalignment is permissible at the joint. See also... Figure 4In this embodiment, for reasons such as installation, transportation, and manufacturing, the plate part connected to the first port 21 is formed by splicing a first sub-plate 231 and a second sub-plate 232. The second sub-plate 232 is disposed on top of the first sub-plate 231, and the projection of the lower boundary of the second sub-plate 232 on the horizontal plane is located on the side away from the air duct Q, which is the projection of the upper boundary of the first sub-plate 231 on the horizontal plane. Thus, the first sub-plate 231 can receive the oil flowing down from the second sub-plate 232, preventing it from dripping directly downwards. The second sub-plate 232 can form a third flange 2313 on both sides along the width direction of the range hood, and the third flange 2313 is connected to the housing 1. The first sub-plate 231 may include a first portion 2311 extending in the same direction as the second sub-plate 232 and a second portion 2312 extending laterally from the upper end of the first portion 2311. The first portion 2311 extends downward from the end of the second portion 2312 near the air duct Q, and the end of the second portion 2312 away from the first portion 2311 can be connected to the housing 1. The end of the second portion 2312 connected to the housing 1 may have a fourth flange 2313, which extends downward. The connections between each flange and the housing 1 are detachable. The second portion 2312 facilitates the installation of the first sub-plate 231 and can guide the oil flowing down from the second sub-plate 232 towards the wall of the housing 1, and then continue to guide it downward.

[0057] A noise reduction cavity Q1 (acoustic trap) is formed between the enclosure 1 and the wall of the air duct Q in the width direction. At least a portion of the noise reduction cavity Q1 is surrounded by an oncoming surface and / or an oncoming airflow surface. Sound-absorbing material or structure 26 is provided inside the noise reduction cavity Q1 to absorb noise entering the cavity. The sound-absorbing material or structure 26 is preferably sound-absorbing cotton. Since each panel 23 is detachably connected to the enclosure 1, it is also convenient to replace the sound-absorbing material or structure 26.

[0058] As a result, noise enters the air duct Q from the second port 22 downwards. Since the first frontal surface 251 protrudes to the right relative to the second port 22, some noise passes through the plate area corresponding to the first frontal surface 251 and enters the corresponding noise reduction cavity Q1. It then undergoes multiple reflections and interferences inside until the sound wave energy is exhausted or only a small portion passes through and re-enters the air duct Q. Meanwhile, some noise is reflected to the first airflow surface 241 opposite to the first frontal surface 251, and then reflects multiple times between the opposing frontal and airflow surfaces, consuming energy. Only a small portion of the noise passes through the first port 21.

[0059] At least a portion of the two plates 23 have openings, such as openings throughout or at least on the frontal surface, with an opening ratio preferably between 5% and 50%. Furthermore, it is preferable that the openings are uniform, with a diameter of 1 to 10 mm and a spacing of 5 to 20 mm between adjacent openings. When the plates 23 are entirely open, the opening ratio of the portion of each plate 23 near the second port 22 is greater than that near the first port 21. Therefore, when noise enters the air duct Q from the second port 22, it can smoothly enter the noise reduction cavity Q1 due to the larger opening ratio. When it propagates within the noise reduction cavity Q1 to the first port 21, the smaller opening ratio prevents the noise from re-entering the air duct Q.

[0060] The speed of the aforementioned fan 200 can be intelligently voice-controlled. Therefore, the range hood can be equipped with an intelligent voice control module, which includes a controller, a voice receiving module, and a voice parsing module. The voice receiving module can receive user commands, and the voice parsing module can analyze these commands. Based on the analyzed commands, the module controls the range hood to perform corresponding operations, thereby achieving intelligent control of the range hood and improving the user experience. Of course, the dimensions of the aforementioned duct Q and the dimensions of the sound-absorbing material or structure 26 still need to meet the operating conditions under intelligent control.

Claims

1. A range hood, comprising a smoke inlet, a fan (200), and an air intake channel (100) disposed between the smoke inlet and the fan (200); the air intake channel (100) comprises a housing (1) and an air duct (Q) located within the housing (1), the air duct (Q) having a first port (21) as an airflow inlet and a second port (22) as a noise sound wave inlet, the first port (21) being located below the second port (22); Its features are: The wall of the air duct (Q) includes two walls spaced apart along the front-rear direction of the range hood, with the rear wall at least partially protruding forward.

2. The range hood according to claim 1, characterized in that: Each wall is made up of a panel (23).

3. The range hood according to claim 2, characterized in that: The casing (1) and the two side walls and the plate (23) along the width direction of the range hood together form the air duct (Q).

4. The range hood according to claim 2, characterized in that: Each wall is made of a single-piece plate (23).

5. The range hood according to claim 2, characterized in that: The plate (23) connected to the second port (22) has a first flange (233) on both sides of the range hood along the width direction, which is connected to the housing (1). The first flange (233) extends along the front and rear direction of the range hood.

6. The range hood according to claim 5, characterized in that: The box (1) has a first opening (11) corresponding to the first port (21) and a second opening (12) corresponding to the second port (22). The top of the plate (23) connected to the second port (22) is provided with a second flange (234), and the second flange (234) is connected to the edge of the second opening (12).

7. The range hood according to claim 2, characterized in that: The plate (23) connected to the first port (21) is composed of at least two sub-plates arranged vertically and horizontally.

8. The range hood according to claim 7, characterized in that: The plate (23) portion connected to the first port (21) includes a first sub-plate (231) connected to the first port (21) and a second sub-plate (232) disposed on the first sub-plate (231), wherein the projection of the lower boundary of the second sub-plate (232) on the horizontal plane is located on the side away from the air duct (Q) from the projection of the upper boundary of the first sub-plate (231) on the horizontal plane.

9. The range hood according to claim 8, characterized in that: The second sub-plate (232) has a third flange (235) on both sides of it along the width direction of the range hood, which is connected to the housing (1). The third flange (235) extends along the front and rear direction of the range hood.

10. The range hood according to claim 8, characterized in that: The first sub-plate (231) includes a first portion (2311) extending in the same direction as the second sub-plate (232).

11. The range hood according to claim 10, characterized in that: The first sub-plate (231) also includes a second part (2312) extending from the upper end of the first part (2311) in a direction away from the air duct (Q), the end of the second part (2312) away from the first part (2311) having a fourth flange (2313) connected to the housing (1), the fourth flange (2313) extending downward.

12. The range hood according to claim 2, characterized in that: The wall surface constituting the air duct (Q) includes at least: A sound-facing surface, which faces the direction of sound wave input and impacts the sound wave, wherein the sound-facing surface is a wall surface that allows noise to pass through; and The frontal surface faces the direction of airflow input and impacts the airflow. One of the plates (23) has at least an acoustic surface and the other plate (23) has at least an airflow surface.

13. The range hood according to claim 12, characterized in that: At least some of the plates (23) on the front and rear sides of the air duct (Q) have openings.

14. The range hood according to claim 13, characterized in that: The opening ratio of the plates (23) on both sides of the air duct (Q) is 5% to 50%.

15. The range hood according to claim 13, characterized in that: The plates (23) on both sides of the air duct (Q) are opened as a whole or at least on the front side.

16. The range hood according to claim 15, characterized in that: The plates (23) on both sides of the air duct (Q) are uniformly perforated.

17. The range hood according to claim 16, characterized in that: The diameter of the openings on the plate (23) is 1 to 10 mm, and the spacing between adjacent openings is 5 to 20 mm.

18. The range hood according to claim 15, characterized in that: The plates (23) on both sides of the air duct (Q) are opened as a whole, and the opening ratio of the part near the second port (22) is greater than that of the part near the first port (21).

19. The range hood according to claim 13, characterized in that: The sound-facing surface includes a first sound-facing surface (251) connected to the second port (22) and a second sound-facing surface (252) connected to the first port (21). The airflow-facing surface includes a first airflow-facing surface (241) connected to the first port (21) and a second airflow-facing surface (242) connected to the second port (22). Along the front-back direction of the range hood, the first sound-facing surface (251) and the first airflow-facing surface (241) are located on the same side of the air duct (Q), and the second sound-facing surface (252) and the second airflow-facing surface (242) are located on the same side of the air duct (Q).

20. The range hood according to claim 19, characterized in that: The first frontal surface (251) and the second frontal surface (242) are connected by curved surfaces (253), and the first frontal surface (241) and the second frontal surface (252) are connected by curved surfaces (253), which are closed walls.

21. The range hood according to claim 1, characterized in that: On a vertical cross-section extending along the front-back direction of the range hood, the top of the rear wall of the duct (Q) has the rearmost first rear point (M1), and the bottom of the rear wall of the duct (Q) has the rearmost second rear point (M2). The line connecting the frontmost first vertex (N1) and the first rear point (M1) corresponding to the protruding part of the rear wall of the duct (Q) is the first connecting line (L1), and the line connecting the first vertex (N1) and the second rear point (M2) is the second connecting line (L2). The included angle between the first connecting line (L1) and the second connecting line (L2) is α, and satisfies 90°<α≤150°.

22. The range hood according to claim 1, characterized in that: On a vertical cross section extending along the front-back direction of the range hood, the bottom of the rear wall of the duct (Q) has the rearmost second rear point (M2). The line connecting the frontmost first vertex (N1) and the second rear point (M2) corresponding to the protruding part of the rear wall of the duct (Q) makes an angle γ with the horizontal plane, and satisfies 60°≤γ≤90°.

23. The range hood according to claim 1, characterized in that: The front wall of the air duct (Q) is a vertical wall or a wall that protrudes forward.

24. The range hood according to claim 23, characterized in that: The front wall of the air duct (Q) is a forward-protruding wall. On the vertical section extending along the front-back direction of the range hood, the top of the front wall of the air duct (Q) has the rearmost third rear point (M3), and the bottom of the front wall of the air duct (Q) has the rearmost fourth rear point (M4). The line connecting the frontmost second vertex (N2) and the third rear point (M3) corresponding to the protruding part of the front wall of the air duct (Q) is the third connecting line (L3), and the line connecting the second vertex (N2) and the fourth rear point (M4) is the fourth connecting line (L4). The included angle between the third connecting line (L3) and the fourth connecting line (L4) is β, and satisfies 120°≤β≤150°.

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