A fan and a range hood

Abstract

This utility model relates to a fan, including a volute and an impeller disposed within the volute. The impeller is eccentrically positioned relative to the volute, and the distance between the impeller and the volute gradually increases based on the rotational flow direction of the exhaust airflow. The fan of this utility model, by eccentrically positioning the impeller relative to the volute, allows the change in the distance between the impeller and the volute to match changes in the flow characteristics of the airflow, thereby reducing noise caused by sudden changes in flow velocity. This structural change allows for a reduction in the volute height without increasing noise, achieving a compact fan design and facilitating the design of wave-shaped fans. This utility model also relates to a range hood, including the aforementioned fan.

Description

Technical Field

[0001] This utility model relates to a fan, and also to a range hood that uses the fan. Background Technology

[0002] In existing technologies, the noise generated by range hoods is annoying to consumers and poses certain health risks. The centrifugal fan is a key component of a range hood, and controlling the noise of a range hood primarily involves controlling the noise of the centrifugal fan. Centrifugal fan noise, based on its source, mainly consists of four parts: outlet noise, inlet noise, motor noise, and casing noise. After the gas is accelerated by the impeller, its flow speed increases. Upon leaving the impeller, the flow channel suddenly expands, causing a sharp change in velocity. The gas is then discharged through the guiding action of the volute, which acts as a collector and is the main source of noise. In existing range hoods, the distance between the impeller and the volute is set at an equal distance, which cannot adapt to changes in the flow velocity within the volute, leading to severe noise problems.

[0003] To reduce the risk of users bumping their heads and to improve the aesthetics of a slim design, existing range hoods are beginning to use slim fans. For example, Chinese invention patent CN113310085B (application number 202110586605.3) and Chinese utility model patent CN215863629U (application number 202122053725.5) both disclose range hoods that use slim fans.

[0004] In thin-profile fans, the compressed volute thickness necessitates a larger impeller diameter, exacerbating noise issues. Furthermore, to match the thinner hood casing, the bottom of the volute is often partially designed as a flat area, further reducing the distance between the volute and impeller and partially disrupting the volute's profile. During fume extraction, the airflow accelerates through this flat area, causing grease to be discharged into building ductwork before it can reach the drip holes at the bottom of the volute, increasing the burden on municipal environmental protection efforts. Utility Model Content

[0005] The first technical problem to be solved by this utility model is to provide a fan that can match the changes in airflow velocity within the volute and reduce noise, in contrast to the above-mentioned prior art.

[0006] The second technical problem to be solved by this utility model is to provide a fan that can effectively separate oil in the plane area of ​​the volute without causing flow loss, in contrast to the above-mentioned prior art.

[0007] The third technical problem to be solved by this utility model is to provide a range hood that uses the aforementioned fan, in contrast to the prior art.

[0008] The technical solution adopted by this utility model to solve the first technical problem mentioned above is: a fan, including a volute and an impeller disposed in the volute, characterized in that: the impeller is eccentrically disposed relative to the volute, and the distance between the impeller and the volute gradually increases based on the rotational flow direction of the airflow.

[0009] To further improve the noise reduction effect, a noise reduction module is provided at the exhaust port of the volute.

[0010] Preferably, the noise reduction module is located on the inner side of the air outlet in the direction of airflow.

[0011] The technical solution adopted by this utility model to solve the second technical problem mentioned above is: the front side of the bottom of the volute has a planar area adapted to the outer shell of the range hood;

[0012] The bottom of the volute is provided with a guide block facing the planar area. The guide block is fan-shaped and has multiple continuous working surfaces on the side facing the planar area. Adjacent working surfaces form a boundary recess for separating oil. The bottom of the volute is provided with an oil drain hole corresponding to the position of each boundary recess.

[0013] Preferably, the action surface includes a first action surface located on the airflow inlet side, a second action surface located on the airflow outlet side, and at least one third action surface located between the first action surface and the second action surface. The first action surface is a plane matching the airflow inlet direction, the second action surface is a small-radius arc surface convex outward of the plane area, and the third action surface is a large-radius arc surface convex outward of the plane area.

[0014] Preferably, at least two third action surfaces are provided, and the arc length of the third action surface located upstream of the airflow is greater than the arc length of the third action surface located downstream of the airflow.

[0015] Preferably, the distance between the region corresponding to the first working surface on the guide block and the impeller in the vertical direction is A, where 1 / 8*R < A < 1 / 3*R.

[0016] Preferably, the distance from the end of the second working surface on the guide block to the impeller in the vertical direction is B, where B > 1 / 5 * R.

[0017] Preferably, the guide block is inclined from front to back along the airflow direction.

[0018] The technical solution adopted by this utility model to solve the third technical problem mentioned above is: a range hood, including the aforementioned fan.

[0019] Compared with existing technologies, the advantages of this invention are as follows: The fan in this invention, by eccentrically aligning the impeller with respect to the volute, allows changes in the distance between the impeller and the volute to match changes in airflow characteristics, thereby reducing noise caused by sudden changes in flow velocity. This structural change enables a reduction in volute height without increasing noise, achieving a compact fan design and facilitating the design of wave-shaped fans.

[0020] Based on this, the present invention also provides a guide block inside the volute to solve the problem of oil discharge caused by the flat area on the volute that matches the outer shell of the range hood, thereby improving the separation effect of oil without causing flow loss. Attached Figure Description

[0021] Figure 1 This is a perspective view of the range hood in the embodiment of this utility model.

[0022] Figure 2 This is a cross-sectional view of the range hood in an embodiment of this utility model.

[0023] Figure 3 This is a cross-sectional view of the fan in an embodiment of this utility model. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] The fan in this embodiment can be used in products with noise reduction requirements, especially in range hoods. Based on the following structure of the fan, it is conducive to the design of a thin fan, and thus also suitable for thin range hoods.

[0026] In this embodiment, a range hood is used as an example, and the fan and the range hood using the fan are described in detail.

[0027] like Figures 1 to 3 As shown, the range hood in this embodiment includes a housing and a fan installed inside the housing.

[0028] like Figures 1 to 3 As shown, the fan includes a volute 1 and an impeller 2 housed within the volute 1. The front side of the volute 1 has an air inlet, and the side wall of the volute 1 has an exhaust port 11. Airflow enters the volute 1 through the air inlet and, under the centrifugal force of the impeller 2, enters the flow channel between the volute 1 and the impeller 2, ultimately exiting through the exhaust port 11. During the flow of air between the volute 1 and the impeller 2, the centrifugal force of the impeller 2 separates oil particles from the fumes. An oil drain hole 13 is located at the bottom of the volute 1. The separated oil particles condense and converge at the bottom of the volute 1, and are then discharged through the oil drain hole 13.

[0029] In this embodiment, the impeller 2 is eccentrically positioned relative to the volute 1, and the distance between the impeller 2 and the volute 1 gradually increases based on the rotational direction of the outward airflow. When used in this manner, after the gas enters the impeller 2 through the inlet, it is accelerated by the impeller 2, increasing its flow velocity. After leaving the impeller 2, it enters the flow channel space between the impeller 2 and the volute 1. Because the distance of the flow channel space gradually increases based on the rotational direction of the outward airflow, the airflow velocity will not suddenly decrease; instead, it will gradually decrease as the distance between the impeller 2 and the volute 1 increases. Because the airflow velocity does not change abruptly, noise caused by sudden changes in airflow velocity is avoided.

[0030] This structural arrangement of the volute 1 and impeller 2 also facilitates increasing the diameter of the impeller 2 and / or reducing the height of the volute 1, achieving a compact fan design without increasing kitchen noise and meeting the design requirements of thin fans.

[0031] To further improve the noise reduction effect, in this embodiment, a noise reduction module 3 is also provided at the exhaust port 11 of the volute 1. The noise reduction module 3 is located on the inner side of the rotation flow direction at the exhaust port 11.

[0032] Furthermore, the range hood in this embodiment adopts a thin design. Due to the size limitation of the outer shell 5 in the range hood, the front side of the bottom of the volute 1 has a flat area 12 that fits the outer shell 5 of the range hood. The rear side of the bottom of the volute 1 is provided with a guide block 4 facing the flat area 12. The guide block 4 is used to guide the flowing fumes and prevent the fumes from being discharged outwards due to accelerated flow through the flow channel of the flat area 12 at the bottom of the volute 1.

[0033] Specifically, the guide block 4 is inclined from front to back along the airflow direction. The guide block 4 is fan-shaped in general. The side of the guide block 4 facing the planar area 12 has multiple continuous working surfaces. Between adjacent working surfaces, there are boundary recesses 40 for separating oil sludge. The bottom of the volute 1 is provided with an oil drain hole 13 corresponding to the position of each boundary recess 40.

[0034] Specifically, the action surface includes a first action surface 41 located on the airflow inlet side, a second action surface 42 located on the airflow outlet side, and at least one third action surface 43 located between the first action surface 41 and the second action surface 42. The first action surface 41 is a plane matching the airflow inlet direction, the second action surface 42 is a small-radius arc surface convex outward of the plane region 12, and the third action surface 43 is a large-radius arc surface convex outward of the plane region 12. At least two third action surfaces 43 are provided, and the arc length of the third action surface 43 located upstream of the airflow is greater than the arc length of the third action surface 43 located downstream of the airflow.

[0035] When the fumes pass through the flow channel between the guide block 4 and the planar area 12 on the volute 1, the first action surface 41 is a plane. The planar shape forces the flow at the leading edge of the guide block 4 to separate in advance, causing the flow to separate suddenly. The second action surface 42 and the third action surface 43 are arc surfaces with different radii. The concave area 40 at the junction between adjacent action surfaces causes a local change in the velocity of the fumes, forming a pressurized vortex at the junction. The vortex separates the oil at the junction. The separated oil flows into the oil drain hole 13 after passing through the prism, and is then discharged through the oil drain hole 13. The convex arc surface of the second action surface 42 has a suction force that promotes the airflow to re-adhere to it, resulting in low flow resistance and avoiding flow loss during the flow of fumes.

[0036] Furthermore, the vertical distance between the area corresponding to the first working surface 41 on the guide block 4 and the impeller 2 is A, where 1 / 8*R < A < 1 / 3*R. If the area corresponding to the first working surface 41 is too close to the impeller 2, the first working surface 41 will obstruct the airflow from the impeller 2. If the area corresponding to the first working surface 41 is too far from the impeller 2, the liquid oil spillage cannot be processed in time, causing the liquid oil spillage to solidify and become stubborn stains.

[0037] The distance between the end of the second working surface 42 on the guide block 4 and the impeller 2 in the vertical direction is B, where B > 1 / 5 * R. This can promote the airflow to re-adhere to the second working surface 42 without causing flow loss and with low flow resistance.

[0038] In this embodiment, the guide block 4, in conjunction with the oil drain hole 13, enables the oil in the volute 1 to be quickly separated and drained, increasing the amount of oil collected.

[0039] The fan in this invention, by eccentrically positioning the impeller 2 relative to the volute 1, allows the change in the distance between the impeller 2 and the volute 1 to match the changes in airflow characteristics, thereby reducing noise caused by sudden changes in flow velocity. This structural change enables a reduction in the height of the volute 1 without increasing noise, achieving a compact fan design and facilitating the design of wave-shaped fans.

[0040] Based on this, the present invention also provides a guide block 4 inside the volute 1 to solve the problem of oil discharge caused by the planar area 12 of the volute 1 matching the range hood shell 5, thereby improving the separation effect of oil without causing flow loss.

[0041] 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 the invention. However, the use of these terms is merely for illustrative purposes and is based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this invention can be arranged in different orientations, these terms indicating direction are for illustrative purposes only and should not be considered as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

Claims

1. A fan comprising a volute (1) and an impeller (2) arranged in the volute (1), characterized in that: The impeller (2) is eccentrically positioned relative to the volute (1), and the distance between the impeller (2) and the volute (1) gradually increases based on the rotational flow direction of the airflow.

2. The fan of claim 1, wherein: A noise reduction module (3) is provided at the air outlet (11) of the volute (1).

3. The fan of claim 2, wherein: The noise reduction module (3) is located on the inside of the air outlet (11) in the direction of rotation.

4. The fan of any one of claims 1 to 3, wherein: The front side of the bottom of the volute (1) has a planar area (12) adapted to the outer shell (5) of the range hood; The bottom rear side of the volute (1) is provided with a guide block (4) facing the planar area (12). The guide block (4) is fan-shaped in general. The side of the guide block (4) facing the planar area (12) has multiple continuous working surfaces. A boundary recess (40) for separating oil sludge is formed between adjacent working surfaces. An oil drain hole (13) is provided at the bottom of the volute (1) corresponding to the position of each boundary recess (40).

5. The fan of claim 4, wherein: The action surface includes a first action surface (41) located on the airflow inlet side, a second action surface (42) located on the airflow outlet side, and at least one third action surface (43) located between the first action surface (41) and the second action surface (42). The first action surface (41) is a plane matching the airflow inlet direction, the second action surface (42) is a small arc-shaped surface convex outward of the plane region (12), and the third action surface (43) is a large arc-shaped surface convex outward of the plane region (12).

6. The fan of claim 5, wherein: The third action surface (43) is provided in at least two forms, and the arc length of the third action surface (43) located upstream of the airflow is greater than the arc length of the third action surface (43) located downstream of the airflow.

7. The fan of claim 5, wherein: The distance between the area corresponding to the first working surface (41) on the guide block (4) and the impeller (2) in the vertical direction is A, 1 / 8*R < A < 1 / 3*R.

8. The fan of claim 7, wherein: The distance from the end of the second working surface (42) on the guide block (4) to the impeller (2) in the vertical direction is B, where B > 1 / 5 * R.

9. The fan of claim 4, wherein: The guide block (4) is inclined from front to back along the airflow direction.

10. A range hood characterized by: Includes the wind turbine as described in any one of claims 1 to 9.

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