Range hood with noise reduction function

Abstract

The utility model relates to a kind of range hood with noise reduction function, comprising: cabinet, including fan frame and the top air outlet plate of fan frame;Fan system, located in the fan frame, including volute, the air outlet of the volute is connected with the air outlet plate;Sound-absorbing box assembly, located in the fan frame, including sound-absorbing box and the sound-absorbing piece in the sound-absorbing box;The sound-absorbing box is connected on the air outlet plate, in the sound-absorbing box on the air outlet plate installation in place state, the sound-absorbing box is attached to the inside of the sidewall of the fan frame.Occupational advantage lies in: it can effectively reduce or eliminate the influence of sound-absorbing box fixing mode on appearance, improve product delicacy.

Description

Technical Field

[0001] This utility model relates to the field of range hood technology, and in particular to a range hood with noise reduction function. Background Technology

[0002] A range hood is a kitchen appliance used to purify the kitchen environment. As users increasingly demand a more refined appearance and quieter operation from range hoods, sound-absorbing boxes are typically installed inside the hood's casing (mainly the fan frame) for noise reduction. Most range hoods install these sound-absorbing boxes by directly screwing the boxes, which contain sound-absorbing cotton, onto the fan cover at the front of the fan (this area is noisiest and is the user's side, making sound absorption and noise reduction most effective). Furthermore, more and more products do not include decorative covers to conceal the screws. As a result, users can directly see the exposed screws from the front when they look up or open a cabinet door (if installed inside a cabinet), affecting the overall refinement and aesthetics. Additionally, because grease and smoke pass through and flow inside the fan cover, sometimes some of it leaks out through the screw holes on the front, further impacting the user's experience and causing cleaning difficulties. Of course, some range hoods use a bracket welded inside the fan cover, and then fix the sound-absorbing components in reverse to the welded directly on the fan cover. Although the screws are not obvious, the fan cover has been welded, and uneven welding marks can be seen on the front, which affects the aesthetics and increases production costs.

[0003] Therefore, existing range hoods still need further improvement. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a range hood with noise reduction function that can effectively reduce or eliminate the impact of the sound absorption box fixing method on the appearance and improve the product's refinement, in light of the current state of the technology.

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

[0006] The housing includes the fan frame and the air outlet plate located on top of the fan frame;

[0007] A fan system, located within the fan frame, includes a volute, the air outlet of which is connected to the air outlet plate.

[0008] A sound-absorbing box assembly is disposed within the fan frame and includes a sound-absorbing box and a sound-absorbing component disposed within the sound-absorbing box;

[0009] The sound-absorbing box is connected to the air outlet plate. When the sound-absorbing box is installed in place on the air outlet plate, the sound-absorbing box is attached to the inner side of the side wall of the fan frame.

[0010] The term "detachable connection" can be understood as a mechanical connection method that allows for separation and reassembly without destructive operation. This includes methods such as snap-fit ​​connections, magnetic connections, and quick-release screws, or a combination of two of these methods.

[0011] By moving the connection point of the sound-absorbing box assembly from the front of the fan cover to the top air outlet plate, screw holes, welding marks, or exposed fasteners are completely invisible from the user's daily viewing angle (eye-level or looking up). The front appearance is clean and flawless, significantly enhancing the product's visual premium feel and overall aesthetics. Traditional fan cover screw holes are prone to oil seepage, but this solution, by installing the sound-absorbing box on the top air outlet plate, completely avoids the problem of oil seeping through screw holes and polluting the appearance. The smooth, non-porous front design also makes cleaning easier, solving a long-standing user concern. The sound-absorbing box is attached to the inner side wall of the fan frame, ensuring that the sound-absorbing component is in close contact with the noise source (volute and airflow path), and the noise reduction effect is not affected by the installation position. Compared to welding bracket solutions, this eliminates the welding process and additional brackets, avoiding unevenness caused by welding deformation, and reducing production costs and assembly complexity.

[0012] Considering that the fan cover plate of the fan frame and the air inlet of the volute are opposite each other, and the space between them is the main air intake path, in order to achieve targeted noise reduction and improve the noise reduction effect, the fan frame includes a fan frame body with an open front and a fan cover plate located at the open front of the fan frame body. The sound-absorbing box is detachably connected to the air outlet plate. When the sound-absorbing box is installed in place on the air outlet plate, the sound-absorbing box is against the inner side of the fan cover plate.

[0013] As an improvement, the volute has an air inlet, and the fan cover is opposite to the air inlet of the volute.

[0014] To simplify the structure of the sound-absorbing box and facilitate the placement and removal of the sound-absorbing components, the sound-absorbing box includes two opposing end walls and a guide wall connecting the two end walls. The guide wall is opposite to the air inlet of the volute and extends inclinedly from top to bottom toward the side where the fan system is located. The two end walls, the corresponding parts of the guide wall and the fan cover plate, and the corresponding parts of the air outlet plate together define a sound-absorbing chamber for placing the sound-absorbing components. Noise reduction holes that communicate with the sound-absorbing chamber are distributed on the guide wall.

[0015] To facilitate the connection between the sound-absorbing box and the air outlet plate, the top edges of the two end walls extend horizontally and are detachably connected to the air outlet plate.

[0016] To simplify the detachable connection structure between the end wall and the air outlet plate, the top edges of both end walls have flanges that fold to one side, and the top of the flanges is provided with buckles. The air outlet plate has a retaining opening for the buckles to be engaged.

[0017] As an improvement, the latch is an insert extending upward from the top of the flange and bent toward the side where the fan system is located. It is conceivable that the latch could also employ a protruding post structure with a limiting stop, and the holding opening could be designed as a bayonet structure connected by two holes of different diameters.

[0018] Considering that the simple snap-fit ​​connection may loosen after long-term use, redundant fixing is required. After the snap-fit ​​on the end wall is engaged with the retaining slot of the air outlet plate, the flange of the end wall is also connected to the air outlet plate by fasteners. Fasteners (such as screws) are used as a secondary locking mechanism to ensure the stability of the sound-absorbing box under strong vibration conditions.

[0019] As an improvement, the two end walls also have vertically extending side edges. When the sound-absorbing box is installed in place on the air outlet plate, the side edges of the two end walls abut against the inner surface of the fan cover. This structural design, by having the side edges of the end walls abut against the fan cover to limit horizontal displacement, enables lateral positioning.

[0020] Furthermore, the two end walls are provided with limiting flanges at their side edges to prevent the sound-absorbing components inside the sound-absorbing box from detaching outwards. These limiting flanges create a physical barrier, preventing the sound-absorbing components from detaching laterally.

[0021] To facilitate the installation and removal of sound-absorbing components from the sound-absorbing box, the connection between the limiting flange and the side edge of the end wall is configured such that the limiting flange can be bent at a corresponding angle relative to the side edge of the end wall under external force. The limiting flange can be manually bent to temporarily enlarge the opening for removing and placing the sound-absorbing component; it can be reset after replacement.

[0022] Considering the turbulent airflow within the fan frame of a range hood, the airflow needs to make a 90° turn as it ascends from the lower air inlet, passes through the housing, and then enters the fan impeller laterally. Generally, the turn near the top of the main air inlet (such as the front side) exacerbates oil-gas separation, leading to the accumulation of oil droplets. When these oil droplets fall downwards, they are easily affected by the airflow and drift, resulting in random downward dripping that is uncontrollable and can easily drip through the oil filter onto the stovetop or into the pot, causing cleaning and cooking problems for the user. Therefore, as an improvement, the guide wall has a guide surface for guiding the airflow, and the profile of the vertical section of this guide surface is an involute.

[0023] Because the airflow guiding surface of the sound-absorbing box adopts an involute curve, it can effectively guide the airflow (which is much weaker than the original large bend separation) into the impeller of the fan system. At the same time, it can also guide the oil caused by the separation of the remaining airflow down along the inner curved surface of the sound-absorbing box, so as not to drip oil randomly downwards. It achieves a dual effect of guiding air and oil, and there is no need to install additional oil guiding parts. It also reduces the airflow bend loss, improves the fan intake effect, and further reduces noise.

[0024] The airflow velocity inside the casing of a typical range hood is approximately 3–10 m / s. The front-end space dimensions of the fan system within the fan frame are: front-to-back range [60mm, 110mm], vertical range [100mm, 300mm], and horizontal range [200mm, 400mm]. The airflow direction is from bottom to top, then turns horizontal or nearly horizontal before entering the fan impeller. To better suit the internal space of the range hood's fan frame and the structure of the fan system, further improvements were made. The involute equation of the vertical section profile of the guide surface is as follows:

[0025] x = R b (cosθ+θsinθ);

[0026] y = R b (sinθ-θcosθ);

[0027] The above R b The base circle radius has a range of values: [180mm, 350mm].

[0028] The θ mentioned above is the involute development angle, with a value range of [120°, 150°].

[0029] Compared with existing technologies, the advantages of this utility model are as follows: This utility model moves the connection position of the sound-absorbing box assembly from the front fan cover to the top air outlet plate. From the user's daily perspective (looking straight ahead or looking up), screw holes, welding marks, or exposed fasteners are completely invisible, resulting in a clean and flawless front appearance that significantly enhances the product's visual appeal and overall aesthetics. The screw holes on the front of traditional fan covers are prone to oil leakage points, while this solution, by installing the sound-absorbing box on the top air outlet plate, completely avoids the problem of oil seeping through the screw holes and polluting the appearance. At the same time, the smooth, non-porous front design makes cleaning easier, solving a long-standing user concern. The sound-absorbing box is attached to the inner side wall of the fan frame, ensuring that the sound-absorbing component is in close contact with the noise source (volute and airflow path), and the noise reduction effect is not affected by the installation position. Compared with the welding bracket solution, this eliminates the welding process and additional brackets, avoiding unevenness caused by welding deformation and reducing production costs and assembly complexity. Attached Figure Description

[0030] Figure 1This is a three-dimensional structural diagram of the range hood according to an embodiment of the present utility model, omitting components such as the smoke collection hood;

[0031] Figure 2 for Figure 1 The exploded view of the range hood shown in the image;

[0032] Figure 3 for Figure 1 The image shows a vertical sectional perspective view of the range hood cut along the front-to-back direction;

[0033] Figure 4 for Figure 1 The image shows a vertical sectional view of the range hood cut along the front-to-back direction;

[0034] Figure 5 This is a three-dimensional structural diagram of the sound-absorbing box according to an embodiment of the present utility model;

[0035] Figure 6 This is a three-dimensional structural diagram of the sound-absorbing box from another angle, according to an embodiment of the present utility model. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0037] In the specification and claims of this utility model, terms indicating direction, such as "front," "rear," "upper," "lower," "left," "right," "side," "top," and "bottom," are used to describe various exemplary structural parts and elements of this utility model. However, the use of these terms is merely for the purpose of explanation and is based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this utility model can be arranged in different orientations, these terms indicating direction are for illustrative purposes only 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.

[0038] Figures 1-6This illustration shows a preferred embodiment of the noise-reducing range hood of this invention. The range hood includes a housing and a fan system 20 disposed within the housing. The fan system 20 is generally a centrifugal fan. The housing generally includes a fan frame 10 and a smoke collection hood disposed at the bottom of the fan frame 10. The inner cavity of the fan frame 10 is connected to the inner cavity of the smoke collection hood. An air inlet 210 is provided on the front side wall of the smoke collection hood, through which external smoke can enter the smoke collection hood. The centrifugal fan is disposed within the fan frame 10. When the centrifugal fan operates, it generates negative pressure, allowing external fumes to be drawn into the smoke collection hood through the air inlet 210. An oil filter is also provided at the air inlet 210 of the smoke collection hood for filtering fumes. An oil cup is provided at the bottom of the smoke collection hood. The oil cup is a long strip extending laterally to collect oil stains flowing down from the smoke collection hood. The front of the smoke hood is also equipped with a smoke baffle that can deflect back and forth relative to the smoke hood. The smoke baffle is connected to the main body of the smoke hood via a hinge mechanism. Specifically, it can deflect forward to open the aforementioned air inlet 210 and deflect backward to block and close the aforementioned air inlet 210. The hinge mechanism used to drive the deflection of the smoke baffle can be a conventional hinge mechanism in the prior art, which will not be described in detail here.

[0039] The fan frame 10 includes a main body and a fan cover 12. The main body of the fan frame 10 has a box-like structure with an open front, and a horizontally extending air outlet plate 13 is fixed to its top, while its bottom is connected to a smoke hood (not shown in the figure). The fan cover 12 is detachably installed at the open front of the main body of the fan frame 10 by screws or clips, forming a closed cavity.

[0040] The centrifugal fan includes a volute 21 and an impeller 22 (details of the impeller 22 are not shown in the figure). The air inlet 210 of the volute 21 faces the front fan cover 12, and the air outlet is directly connected to the top air outlet plate 13. During the operation of the range hood, external fumes enter the fume collection hood, rise into the fan frame 10, and then enter the volute 21 through the air duct between the fan system 20 and the fan cover 12, before being discharged through the air outlet of the volute 21.

[0041] The sound-absorbing box 31 assembly of this embodiment includes a sound-absorbing box 31 and a sound-absorbing component 33 (which may be porous sound-absorbing cotton). The sound-absorbing box 31 can be integrally stamped from sheet metal. The sound-absorbing box 31 includes two opposing end walls 311 and a guide wall 312 connecting the two end walls 311. The guide wall 312 is an arc-shaped wall that extends obliquely from top to bottom towards the volute 21. Noise reduction holes 3120 that communicate with the inner cavity of the sound-absorbing box 31 are evenly distributed on the surface of the guide wall 312. The edges at the junctions of the two end walls 311 and the guide wall 312 are also arc-shaped edges. The top edges 3111 of the two end walls 311 extend horizontally and fold inward to form a flange 3112, and the top of the flange 3112 extends upward to form a clip 3113 (the clip bends towards the volute 21). The side edges 3114 of the two end walls 311 extend substantially vertically to abut against the inner side wall of the fan cover 12. Figure 5 and Figure 6 As can be seen, the top of the sound-absorbing box 31 and the side facing the fan cover 12 are open. From the side, the sound-absorbing box 31 has a triangular structure. The side edge 3114 of the sound-absorbing box 31 is also provided with a manually bendable limiting flange 3115 (the easy-to-bend design of the limiting flange 3115 means that its root strength is relatively weak, which is convenient for workers to operate), which is used to limit the lateral dislodgement of the sound-absorbing component 33.

[0042] In this embodiment, after the sound-absorbing box 31 is installed on the air outlet plate 13, the two end walls 311 of the sound-absorbing box 31, the corresponding parts of the guide wall 312 and the fan cover plate 12, and the corresponding parts of the air outlet plate 13 together define a sound-absorbing chamber. The sound-absorbing component 33 also adopts a structure that matches the contour of the sound-absorbing chamber and fills the sound-absorbing chamber. The noise reduction holes 3120 distributed on the guide wall 312 are in communication with the sound-absorbing chamber.

[0043] Adapted to the top edge 3111 of the aforementioned sound-absorbing box 31, the air outlet plate 13 has a retaining slot 130 at a position corresponding to the insert 3113 of the sound-absorbing box 31. During installation, the sound-absorbing component 33 can be inserted into the sound-absorbing box 31 first. The top flange 3112 and the side limiting flange 3115 of the sound-absorbing box 31 can prevent the sound-absorbing component 33 from falling out. After the sound-absorbing box 31 assembly is completed, the sound-absorbing box 31 can be placed below the air outlet plate 13, so that the buckle on the flange 3112 of the end wall 311 is aligned with the retaining slot 130 (rectangular opening) of the air outlet plate 13. Push the sound-absorbing box 31 upward, and after the buckle is inserted into the retaining slot 130, the bent insert 3113 hooks onto the edge of the retaining slot 130 to achieve initial fixation. After the clips are engaged, the top flange 3112 of the sound-absorbing box 31 is placed against the bottom wall of the air outlet plate 13. Fasteners 4 (such as screws) are then used to pass through the corresponding screw holes of the flange 3112 and the air outlet plate 13 for secondary tightening. When installed in place, the guide wall 312 of the sound-absorbing box 31 is opposite to the air inlet 210 of the volute 21, the side edges 3114 of the two end walls 311 are close to the inner side wall of the fan cover plate 12, and the limiting flange 3115 is in a vertical state to constrain the sound-absorbing component 33. The fan cover plate 12 is also basically in contact with the sound-absorbing component 33 filled in the sound-absorbing box 31. When replacing the sound-absorbing component 33, the limiting flange 3115 is manually bent outward to expand the operating space, the old sound-absorbing cotton is removed and new sound-absorbing cotton is filled in, and finally the limiting flange 3115 is returned to a vertical state.

[0044] Considering that the airflow inside the fan frame 10 of the range hood is relatively turbulent, the airflow needs to make a 90° turn from the lower air inlet 210 upward through the box and then horizontally into the fan impeller 22. Generally, the turn near the top of the air outlet plate 13 of the main air inlet 210 (such as the front side) intensifies the oil-gas separation, which makes it easy for oil droplets to accumulate. When the oil droplets fall downward, they are easily affected by the airflow and drift, resulting in a certain degree of randomness in dripping downward. They are uncontrollable and can easily drip through the oil filter onto the stove surface or into the pot, causing cleaning and cooking trouble for users. Therefore, the guide wall 312 of the sound absorption box 31 in this embodiment has a guide surface 3121 for guiding the airflow. The profile of the vertical section of the guide surface 3121 is an involute. The airflow guiding surface 3121 of the sound-absorbing box 31 adopts an involute curved surface, which can effectively guide the airflow (which is much weaker than the original large bend separation) into the impeller 22 of the fan system 20. At the same time, it can also guide the oil caused by the separation of the remaining airflow down along the inner curved surface of the sound-absorbing box 31, so as not to drip oil randomly downwards. It achieves a dual effect of guiding air and oil, and there is no need to install additional oil guiding parts. It also reduces the airflow bend loss, improves the fan intake effect, and further reduces noise.

[0045] The airflow velocity inside the casing of a typical range hood is approximately 3–10 m / s. The front-end space dimensions of the fan system within the fan frame are: front-to-back [60mm, 110mm], vertical [100mm, 300mm], and horizontal [200mm, 400mm]. The airflow direction is from bottom to top, then turns horizontal or nearly horizontal before entering the fan impeller. To adapt to the internal space of the range hood's fan frame and the structure of the fan system, the involute equation of the vertical section profile of the guide wall's guide surface is as follows:

[0046] x = R b (cosθ+θsinθ);

[0047] y = R b (sinθ-θcosθ);

[0048] The above R b The base circle radius is used as a reference based on the impeller diameter of the fan system, and its value range is: [180mm, 350mm].

[0049] The θ mentioned above is the involute expansion angle, with a value range of [120°, 150°].

[0050] The x and y mentioned above can be understood as points (x, y) on the profile of the vertical section of the guide surface.

[0051] The above design allows the radius of curvature of the vertical section of the guide surface to be greater than 20mm, thereby avoiding oil droplet separation caused by sharp bends.

Claims

1. A range hood with noise reduction function, comprising: The housing includes a fan frame (10) and an air outlet plate (13) located on top of the fan frame (10); The fan system (20) is located inside the fan frame (10) and includes a volute (21). The air outlet of the volute (21) is connected to the air outlet plate (13). The sound-absorbing box (31) assembly is disposed within the fan frame (10) and includes the sound-absorbing box (31) and the sound-absorbing component (33) disposed within the sound-absorbing box (31); The sound-absorbing box (31) is connected to the air outlet plate (13). When the sound-absorbing box (31) is installed on the air outlet plate (13), the sound-absorbing box (31) is attached to the inner side of the side wall of the fan frame (10).

2. The range hood with noise reduction function according to claim 1, characterized in that: The fan frame (10) includes a fan frame body (11) with an open front and a fan cover plate (12) located at the open front of the fan frame body (11). The sound-absorbing box (31) is detachably connected to the air outlet plate (13). When the sound-absorbing box (31) is installed on the air outlet plate (13), the sound-absorbing box (31) is attached to the inner side of the fan cover plate (12).

3. The range hood with noise reduction function according to claim 2, characterized in that: The volute (21) has an air inlet (210), and the fan cover (12) is opposite to the air inlet (210) of the volute (21).

4. The range hood with noise reduction function according to claim 3, characterized in that: The sound-absorbing box (31) includes two opposing end walls (311) and a guide wall (312) connected between the two end walls (311). The guide wall (312) is opposite to the air inlet (210) of the volute (21) and extends obliquely from top to bottom toward the side where the fan system (20) is located. The two end walls (311), the guide wall (312), the corresponding parts of the fan cover plate (12), and the corresponding parts of the air outlet plate (13) together define a sound-absorbing chamber for placing the sound-absorbing component (33). Noise reduction holes (3120) that communicate with the sound-absorbing chamber are distributed on the guide wall (312).

5. The range hood with noise reduction function according to claim 4, characterized in that: The top edges (3111) of the two end walls (311) extend horizontally and are detachably connected to the air outlet plate (13).

6. The range hood with noise reduction function according to claim 5, characterized in that: The top edges (3111) of both end walls (311) have flanges (3112) that fold to one side, and the top of the flanges (3112) is provided with buckles. The air outlet plate (13) has a retaining opening (130) for the buckles to be inserted into.

7. The range hood with noise reduction function according to claim 6, characterized in that: The buckle is an insert (3113) that extends upward from the top of the flange (3112) and bends toward the side where the fan system (20) is located.

8. The range hood with noise reduction function according to claim 6, characterized in that: After the buckle of the end wall (311) is inserted into the retaining hole (130) of the air outlet plate (13), the flange (3112) of the end wall (311) is also connected to the air outlet plate (13) by a fastener (4).

9. The range hood with noise reduction function according to claim 5, characterized in that: The two end walls (311) also have vertically extending side edges (3114) that abut against the inner side of the fan cover (12) when the sound-absorbing box (31) is installed on the air outlet plate (13).

10. The range hood with noise reduction function according to claim 9, characterized in that: The two end walls (311) are also provided with limiting flanges (3115) at the side edges (3114) to restrict the sound-absorbing element (33) inside the sound-absorbing box (31) from falling outward.

11. The range hood with noise reduction function according to claim 10, characterized in that: The connection position between the limiting flange (3115) and the side edge (3114) of the end wall (311) is configured such that the limiting flange (3115) can be bent at a corresponding angle relative to the side edge (3114) of the end wall (311) under the action of external force.

12. The range hood with noise reduction function according to claim 4, characterized in that: The guide wall (312) has a guide surface (3121) for guiding the airflow, and the profile of the vertical section of the guide surface (3121) is an involute.

13. The range hood with noise reduction function according to claim 12, characterized in that: The involute equation of the profile of the vertical section of the guide surface is as follows: x=R b (cosθ+θsinθ); y=R b (sinθ-θcosθ); The above R b The base circle radius has a range of values: [180mm, 350mm]. The θ mentioned above is the involute expansion angle, with a value range of [120°, 150°].

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