Range hood

Abstract

The invention belongs to the technical field of household appliances, and particularly relates to a range hood. The range hood comprises a smoke collecting cavity, a fan, a cover plate and a flow guide structure, and a smoke inlet is formed in the front side of the smoke collecting cavity; the fan is arranged in the smoke collecting cavity; the cover plate is movably arranged on the front side of the smoke collecting cavity, and the cover plate can slide in the front-back direction relative to the smoke collecting cavity so as to be switched between a first position attached to the front side face of the smoke collecting cavity and a second position spaced from the front side face of the smoke collecting cavity; the flow guide structure is arranged at the smoke inlet so as to divide the smoke inlet into a plurality of flow dividing channels to uniformize airflow. The flow guide structure can guide airflow to enter the smoke collecting cavity through the multiple flow dividing channels, so that the airflow and the flow velocity at the smoke inlet are uniformly distributed, fluid disturbance and velocity gradient are weakened, airflow separation and turbulent flow development are inhibited, airflow resistance is reduced, directional high-speed conveying of oil smoke is achieved, and air loss at the smoke inlet is reduced; and the performance of the range hood is improved.

Description

Technical Field

[0001] This invention relates to the field of household appliance technology, and more particularly to a range hood. Background Technology

[0002] In range hoods and other fume treatment equipment, the fume collection chamber is the core component for collecting and guiding fumes. Its inlet structure directly determines the equipment's fume capture efficiency and fan performance. Straight-plate fume collection chambers are widely used in miniaturized equipment due to their simple inlet structure and small footprint.

[0003] Existing smoke collection chambers, limited by installation space and aesthetic design, are often confined to a narrow thickness of 90mm-150mm. This constraint results in structural defects in traditional horizontal telescopic covers. When airflow enters the smoke inlet through the gap between the cover and the smoke collection chamber, it tends to concentrate at the edge of the inlet, leading to uneven airflow distribution and high wind resistance. Consequently, the maximum effective flow area can only meet 50%-70% of the rated demand, resulting in insufficient fan intake capacity, airflow distortion, and intensified turbulence, leading to a significant increase in inlet losses. Increased fan inlet losses directly cause a decrease in air volume and air pressure, accompanied by increased noise and energy consumption, severely impacting performance. Summary of the Invention

[0004] The purpose of this invention is to provide a range hood that can solve the problems of uneven airflow distribution, high wind resistance, and large air volume loss at the inlet of ultra-thin range hoods with telescopic covers.

[0005] To achieve this objective, the present invention adopts the following technical solution: A range hood, comprising: A smoke collection chamber, with a smoke inlet located at the front side of the smoke collection chamber; The fan is installed inside the smoke collection chamber; A cover plate is movably disposed on the front side of the smoke collection chamber. The cover plate can slide relative to the smoke collection chamber in the front-back direction to switch between a first position that fits against the front side of the smoke collection chamber and a second position that is spaced apart from the front side of the smoke collection chamber. A flow guiding structure is provided at the smoke inlet to divide the smoke inlet into multiple flow channels to ensure uniform airflow.

[0006] As an optional solution for the aforementioned range hood, the flow guiding structure includes multiple flow guiding plates, which are arranged crosswise within the smoke inlet to divide the smoke inlet into multiple flow channels.

[0007] As an alternative to the aforementioned range hood, multiple baffles intersect at the center and radiate outwards, with the center of the baffles coinciding with the center of the smoke inlet, and the included angle between any two adjacent baffles being equal.

[0008] As an alternative to the aforementioned range hood, the smoke inlet is circular, and the baffle plate extends radially along the smoke inlet; And / or, the flow guiding structure also includes an annular support member, which is cross-connected to each flow guide plate.

[0009] As an optional solution for the aforementioned range hood, an arc structure is provided at the smoke inlet. The arc structure includes an arc guide surface protruding towards the inside of the smoke inlet, and the airflow guiding structure is connected to the arc guide surface.

[0010] As an optional solution for the aforementioned range hood, the radius of curvature of the arc guide surface is 15mm-25mm.

[0011] As an optional solution for the aforementioned range hood, the fan includes a housing with an air inlet communicating with the smoke inlet. The edge of the housing surrounding the air inlet curves and extends inward toward the smoke inlet to form an arc structure, and the arc guide surface abuts against the edge of the smoke collection chamber surrounding the smoke inlet.

[0012] As an optional solution for the aforementioned range hood, the fan also includes an impeller. One axial end of the impeller is provided with an annular flange along the circumference of the smoke inlet. An arc-shaped guide surface extends into the annular flange and is spaced apart from the annular flange to form a sealing gap.

[0013] As an optional solution for the aforementioned range hood, the sealing gap is 0.5mm-2mm.

[0014] As an alternative to the aforementioned range hood, the side of the cover facing the smoke inlet is recessed to form a groove, and a boss is formed on the side of the cover away from the smoke inlet. The projection of the groove onto the smoke collection chamber in the front-to-back direction covers at least part of the smoke inlet.

[0015] As an alternative to the aforementioned range hood, the sidewall of the groove gradually slopes towards the edge of the cover plate from front to back; And / or, the depth of the groove is 10mm-20mm; And / or, the radial dimension of the groove is 1.5-2 times the radial dimension of the smoke inlet; And / or, the boss includes at least two frustum segments connected in sequence, the diameter of two adjacent frustum segments increasing from front to back, and the diameter of the boss at the end closest to the smoke inlet along the axial direction is 2-3 times the diameter of the other end along the axial direction.

[0016] As an optional solution for the aforementioned range hood, a first sliding guide is provided on the cover plate, and a second sliding guide is provided inside the smoke collection chamber. The first and second sliding guides slide together in the front-back direction.

[0017] The beneficial effects of this invention are: The range hood provided by this invention uses a flow guiding structure to adapt to the telescopic cover, guiding the airflow through multiple diversion channels into the smoke collection chamber. This makes the airflow and velocity distribution at the smoke inlet uniform, weakens fluid disturbance and velocity gradient, thereby suppressing airflow separation and turbulence development, which helps to reduce airflow resistance, achieve directional high-speed delivery of fumes, reduce airflow loss at the smoke inlet, and improve the performance of the range hood.

[0018] Multiple guide vanes are intersected inside the smoke inlet to divide the smoke inlet into multiple diversion channels. This allows the airflow passing through the smoke inlet to enter the fan through multiple diversion channels under the action of the multiple guide vanes, thereby improving the uniformity of airflow distribution at the smoke inlet.

[0019] The annular support is cross-connected to each guide plate. On the one hand, this can improve the stability of the guide plate and reduce the vibration displacement of the guide structure, so as to effectively resist the structural displacement caused by the vibration generated during the operation of the fan, ensure the stable installation of the guide plate, and guarantee the stability of the guide effect. On the other hand, it can increase the number of diversion channels, which is conducive to improving the uniformity of airflow and velocity.

[0020] The arc structure at the flue gas inlet is equipped with an arc guide surface, which can guide the airflow to change direction and make the airflow direction transition smoothly. This can reduce the airflow turning gradient by 30%-50% and reduce the area of ​​the vortex region at the end of the guide plate by 60%-80%, thereby further optimizing the airflow field distribution, reducing local energy loss, and improving the performance of the fan.

[0021] The cover plate has a groove on the side facing the smoke inlet and a protrusion on the opposite side. The protrusion increases the strength of the cover plate, enabling it to meet the requirements of high temperature, high oil fume, and high wind pressure, and preventing deformation or damage. The groove guides the airflow along its inner wall, thus guiding the airflow direction and allowing sufficient space to gradually adjust its flow direction. This ensures that at least part of the airflow flows approximately perpendicular to the smoke inlet, preventing airflow from concentrating at the circumferential edge of the smoke inlet. This promotes even airflow distribution at the smoke inlet, increases the effective flow area of ​​the smoke inlet, significantly improves airflow volume, reduces airflow loss, and ultimately enhances the performance of the range hood. The cover plate is connected to the smoke collection chamber through a sliding guide assembly, which increases the support and fixation of the cover plate and makes the movement of the cover plate more stable. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the range hood provided by the present invention; Figure 2 This is a schematic diagram of the structure of the range hood provided by the present invention when the cover plate is not installed; Figure 3 This is a partial structural diagram of the smoke inlet position in the range hood provided by the present invention; Figure 4 This is a cross-sectional view of the range hood provided by the present invention without the cover plate installed; Figure 5 yes Figure 4 A magnified view of a section at point A in the middle; Figure 6 This is a schematic diagram of the structure of the cover plate provided by the present invention; Figure 7 This is a schematic diagram of the sliding guide assembly provided by the present invention.

[0023] In the picture: 10. Smoke collection chamber; 11. Smoke inlet; 12. Sealing gap; 20. Fan; 21. Impeller; 22. Shell; 221. Arc guide surface; 30. Cover plate; 31. Groove; 32. Boss; 40. Flow guiding structure; 41. Flow guide plate; 42. Annular support; 50. Sliding guide assembly; 51. First sliding guide; 52. Second sliding guide. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0025] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0028] like Figure 1 As shown, this invention provides a range hood, including a smoke collection chamber 10, a fan 20, a cover plate 30, and a telescopic drive mechanism. The front side of the smoke collection chamber 10 has a smoke inlet 11. The fan 20 is disposed within the smoke collection chamber 10. The cover plate 30 is movably disposed on the front side of the smoke collection chamber 10. The telescopic drive mechanism is disposed within the smoke collection chamber 10 and connected to the cover plate 30, so as to drive the cover plate 30 to slide relative to the smoke collection chamber 10 in a front-back direction, allowing the cover plate 30 to switch between a first position abutting the front side of the smoke collection chamber 10 and a second position spaced apart from the front side of the smoke collection chamber. When the range hood is working, the cover plate 30 moves to the second position, the fan 20 starts, and a negative pressure is formed at the smoke inlet 11, driving the fumes through the gap between the cover plate 30 and the smoke collection chamber 10 into the smoke inlet 11, and then discharged outdoors under the drive of the fan 20, achieving the effect of purifying indoor air. When the cover plate 30 is in the first position, the cover plate 30 fits against the front side of the smoke collection chamber 10 to block the smoke inlet 11, which has a good sealing effect on the smoke inlet 11. At the same time, it reduces the overall size of the range hood in the front-to-back direction to reduce the space occupied.

[0029] In some embodiments, when the cover plate 30 is in the second position, the distance between the cover plate 30 and the front side of the smoke collection chamber 10 is 80mm-120mm. This ensures that a sufficiently large airflow channel is formed between the cover plate 30 and the smoke collection chamber 10 to guarantee the air intake effect, while also preventing the cover plate 30 from extending too far and interfering with the stove or cookware.

[0030] In some embodiments, the projection of the cover plate 30 onto the smoke collection chamber 10 in the front-to-back direction covers the smoke inlet 11. That is, the size of the cover plate 30 is larger than the size of the smoke inlet 11, and the cover plate 30 can completely block the smoke inlet 11 from the front. When the cover plate 30 moves to the second position, a large negative pressure zone is formed between the cover plate 30 and the front side of the smoke collection chamber 10, which can increase the collection range of oil fumes, improve the capture effect of oil fumes, and reduce the escape of oil fumes.

[0031] In some embodiments, the height dimension of the cover plate 30 is greater than the maximum dimension of the smoke inlet 11 along the height direction, and the left-right dimension of the cover plate 30 is greater than the left-right dimension of the smoke inlet 11, so that the cover plate 30 can completely cover the smoke inlet 11. In order to increase the negative pressure zone formed between the cover plate 30 and the front side of the smoke collection chamber 10, and to ensure sufficient negative pressure redundancy at the circumferential edge of the smoke inlet 11, the maximum dimension of the smoke inlet 11 along the left-right direction can be 60%-70% of the left-right dimension of the cover plate 30, so as to ensure redundancy.

[0032] It should be noted that the front side of the range hood refers to the side of the range hood closest to the user, while the back side refers to the side of the range hood facing the wall where it is installed. Correspondingly, the left and right sides of the range hood are defined as the left and right sides when the user is facing it.

[0033] In some embodiments, the front side of the smoke collection chamber 10 is vertically arranged, and the size of the smoke collection chamber 10 in the front-to-back direction is 90mm-150mm, so that the thickness of the smoke collection chamber 10 is thinner and occupies less space, thereby improving the appearance after installation.

[0034] Preferably, the smoke collection chamber 10 has a front-to-back dimension of 60mm-100mm and a thinner thickness to meet the space requirements of various installation scenarios.

[0035] In traditional range hoods, when cooking fumes flow through the gap between the cover plate 30 and the front side of the smoke collection chamber 10 to the smoke inlet 11, the fumes tend to concentrate at the edges of the smoke inlet 11. That is, there is less fumes at the center of the smoke inlet 11 and more at the edges. This results in greater resistance for the fumes as they pass through the smoke inlet 11, and the actual airflow area of ​​the smoke inlet 11 is small. This can easily lead to insufficient air intake capacity of the fan 20, causing airflow distortion and intensified turbulence. Consequently, the airflow loss at the smoke inlet 11 increases significantly, the air pressure decreases, and noise and energy consumption increase, seriously affecting the performance.

[0036] To solve the above problems, such as Figure 2 As shown, in this embodiment, a flow guiding structure 40 is provided at the smoke inlet 11. The flow guiding structure 40 is used to uniformly distribute the airflow at the smoke inlet 11. By providing the flow guiding structure 40 to adapt to the telescopic cover 30, the airflow is guided through the smoke inlet 11 into the smoke collection chamber 10, realizing the directional high-speed delivery of oil fumes. This makes the airflow and velocity distribution at the smoke inlet 11 uniform, weakens fluid disturbance and velocity gradient, thereby suppressing airflow separation and turbulence development, which helps to reduce the air volume loss at the smoke inlet 11 and improve the performance of the range hood.

[0037] In some embodiments, the flow guiding structure 40 includes multiple guide plates 41, which are intersected within the smoke inlet 11 to divide the smoke inlet 11 into multiple flow distribution channels. The airflow passing through the smoke inlet 11 enters the fan 20 through these multiple flow distribution channels under the action of the multiple guide plates 41. This improves the uniformity of airflow distribution at the smoke inlet 11, helps reduce the velocity gradient, lowers airflow resistance, thereby suppressing turbulence development and reducing airflow loss.

[0038] In some embodiments, to improve the uniform airflow effect, multiple guide vanes 41 intersect at their centers and radiate outwards, with the center of each guide vane 41 coinciding with the center of the smoke inlet 11, and the included angle between any two adjacent guide vanes 41 being equal. The multiple guide vanes 41 form a multi-spoke support structure, which can divide the space within the smoke inlet 11 into multiple circumferentially arranged diversion channels, resulting in better flow uniformity.

[0039] In some embodiments, the smoke inlet 11 is circular, and each guide plate 41 extends radially along the smoke inlet 11. Multiple guide plates 41 intersect at the center of the smoke inlet 11, so that the multiple diversion channels formed are of equal size, which is beneficial to improving the flow equalization effect.

[0040] In some other embodiments, the smoke inlet 11 may also be rectangular, triangular or other polygonal, and the specific shape of the smoke inlet 11 can be set according to actual needs.

[0041] To improve the stability of the guide plate 41, the flow guiding structure 40 also includes an annular support member 42. The annular support member 42 extends circumferentially along the smoke inlet 11 and is cross-connected to each guide plate 41. On the one hand, this can improve the stability of the guide plate 41 and reduce the vibration displacement of the flow guiding structure 40, so as to effectively resist the structural displacement caused by the vibration generated during the operation of the fan, ensure that the guide plate 41 is installed firmly, and ensure the stability of the flow guiding effect. On the other hand, it can increase the number of diversion channels, which is beneficial to improve the uniformity of airflow and velocity.

[0042] In some embodiments, the radial dimension between the intersection of the annular support 42 and each guide plate 41 and the center of the smoke inlet 11 is 0.4-0.6 times the radius of the smoke inlet 11, preferably 0.5 times. Exemplarily, the annular support 42 is a circular ring plate, the circle of which coincides with the circle of the smoke inlet 11, and the radius of the annular support 42 is 0.4-0.6 times the radius of the smoke inlet 11. This arrangement provides two support points for each guide plate 41, and the two support points are evenly distributed, which helps to improve the strength and stability of the guide structure 40, better resisting the vibration and resistance generated during the operation of the fan 20, thereby ensuring the stability of the guide effect.

[0043] In some embodiments, the surfaces of the guide plate 41 and the annular support 42 are parallel to the front-back direction. That is, the surfaces of the guide plate 41 and the annular support 42 are parallel to the axis of the smoke inlet 11. The airflow through the smoke inlet 11 can flow along the surfaces of the guide plate 41 and the annular support 42 into the fan 20 to provide guidance for the airflow and make the airflow enter the fan 20 more smoothly.

[0044] In some embodiments, the number of guide plates 41 is 2-5, preferably 3-4, in order to ensure the number of diversion channels while avoiding the flow area of ​​a single diversion channel being too small, thereby ensuring the performance of the fan 20.

[0045] For example, such as Figure 2 and Figure 3 As shown, there are 3 baffles 41. The 3 baffles 41 and the annular support 42 cooperate to form 12 diversion channels. The 12 diversion channels are arranged in two rows along the radial direction of the smoke inlet 11. The flow area of ​​the outer row of diversion channels is larger than that of the inner row of diversion channels.

[0046] In some other embodiments, the multiple guide vanes 41 can also be arranged in a cross pattern, or the smoke inlet 11 can be divided into multiple diversion channels.

[0047] In some embodiments, the deflector 41 is made of stainless steel sheet to provide excellent high-temperature resistance and corrosion resistance, enabling it to withstand long-term erosion in oil fume environments and ensuring its service life. Optionally, the thickness of the deflector 41 can be 1.5mm-2.5mm to ensure structural strength.

[0048] In some embodiments, the surface of the baffle plate 41 is coated with an anti-stick coating to reduce oil fume adhesion, thereby reducing the amount of oil fume adhesion by more than 90% and shortening the cleaning and maintenance time of the range hood by 60%-70%, solving the problem of traditional baffle plates 41 being prone to oil accumulation and difficult to clean.

[0049] To avoid interference between the guide structure 40 and the fan 20, the end of the guide plate 41 facing away from the cover plate 30 is spaced apart from the impeller 21 inside the fan 20 to ensure that the impeller 21 can rotate normally.

[0050] In some embodiments, an arc-shaped structure is provided at the smoke inlet 11. The arc-shaped structure includes an arc-shaped guide surface 221 protruding towards the center of the smoke inlet 11, and both ends of the guide plate 41 are connected to the arc-shaped guide surface 221. By providing the arc-shaped guide surface 221, the airflow can be guided to change direction, making the airflow direction transition smoothly. This can reduce the airflow turning gradient by 30%-50% and reduce the vortex area at the end of the guide plate 41 by 60%-80%, thereby further optimizing the airflow field distribution, reducing local energy loss, and improving the performance of the fan 20.

[0051] In some embodiments, such as Figure 4 and Figure 5As shown, the fan 20 includes a housing 22, an impeller 21 rotatably disposed within the housing 22, and a motor. The motor is connected to the impeller 21 to drive the impeller 21 to rotate. The housing 22 has an air inlet communicating with the smoke inlet 11. The edge of the housing 22 surrounding the air inlet curves inward towards the smoke inlet 11 to form an arc structure, and the arc guide surface abuts against the edge of the smoke collection chamber 10 surrounding the smoke inlet 11. The arc structure on the housing 22 helps ensure the positional accuracy of the arc guide surface 221 and the impeller 21, thus improving the airflow guidance effect.

[0052] In some other embodiments, the arc structure can also be formed by the smoke collection cavity 10. Specifically, the edge of the smoke collection cavity 10 surrounding the smoke inlet 11 bends and extends inward toward the smoke inlet 11 to form an arc structure, which can also guide the airflow direction and reduce the airflow turning gradient.

[0053] In some embodiments, the radius of curvature of the arc guide surface 221 is 15mm-25mm, preferably 20mm. If the radius of curvature of the arc guide surface 221 is less than 15mm, the curvature of the arc guide surface 221 is small, and the guiding effect on airflow direction is small. If the radius of curvature of the arc guide surface 221 is greater than 25mm, the curvature of the arc guide surface 221 is too large, which will lead to fluid blockage, high fluid resistance, and is not conducive to optimizing the airflow field distribution and reducing local energy loss.

[0054] In some embodiments, such as Figure 5 As shown, one axial end of the impeller 21 faces the air inlet, and the arc-shaped guide surface 221 extends into the impeller 21 and is spaced apart from the inner wall of the impeller 21 to form a sealing gap 12. By setting the sealing gap 12, it is possible to avoid interference between the arc structure and the impeller 21, which would affect the normal rotation of the impeller 21, and also to reduce airflow leakage through the gap, thus ensuring the performance of the fan 20.

[0055] Taking into account both the motion requirements and sealing requirements of the impeller 21, in some embodiments, the sealing gap 12 can be 0.5mm-2mm. Exemplarily, the sealing gap is 0.5mm, 1mm, 1.5mm, or 2mm. Within this range, the sealing gap 12 can effectively prevent leakage.

[0056] Combination Figure 1 and Figure 6As shown, in some embodiments, a groove 31 is provided on the side of the cover plate 30 facing the smoke inlet 11, and a boss 32 is formed at a corresponding position on the side of the cover plate 30 away from the smoke inlet 11. The projection of the groove 31 on the smoke collection chamber 10 in the front-back direction covers at least part of the smoke inlet 11. The boss 32 increases the strength of the cover plate 30, enabling it to meet the requirements of high temperature, high oil fume, and high wind pressure, and preventing deformation or damage. The groove 31 increases the flow channel space formed by the cover plate 30 and the smoke collection chamber 10 when the cover plate 30 is in the second position. It is also positioned opposite to the smoke inlet 11, guiding the airflow to enter the groove 31 first and then turning under the guidance of the inner wall of the groove 31. This allows the airflow to gradually adjust its flow direction with sufficient space, thus ensuring that the airflow smoothly enters the smoke inlet 11. This prevents the airflow from concentrating at the circumferential edge of the smoke inlet 11, reduces the risk of local vortices, and ensures the continuity, uniformity, and low resistance of the airflow, thereby improving the performance of the fan 20. The corresponding positions of the groove 31 and the boss 32 make the overall thickness of the cover plate 30 uniform, eliminating the need to increase local thickness. This helps reduce material usage and the weight of the cover plate 30, which is beneficial for the development of thinner and lighter range hoods.

[0057] By setting protrusions 32 and grooves 31 on the cover plate 30, the aerodynamic guiding performance and structural rigidity of the cover plate 30 can be improved. This not only optimizes the airflow velocity field distribution at the smoke inlet 11, but also significantly enhances the bending rigidity and structural stability of the cover plate 30, making it suitable for range hoods with high air volume and low noise requirements.

[0058] To prevent the protrusion 32 from interfering with the stove or cookware, in some embodiments, the depth of the groove 31 can be 10mm-20mm. It is understood that when the cover plate 30 is in the second position, the extension distance of the cover plate 30 is between 80mm and 120mm. The protrusion 32 is provided on the cover plate 30, and the distance between the foremost end of the protrusion 32 and the smoke collection chamber 10 is between 90mm and 140mm, which will not interfere with the stove or cookware and can meet the user's cooking space requirements; at the same time, it helps to increase the strength of the cover plate 30.

[0059] In order to better guide the airflow to turn and enter the smoke inlet 11, in some embodiments, the diameter of the groove 31 is 1.5 to 2 times the diameter of the smoke inlet 11, so that the projection of the groove 31 can completely cover the smoke inlet 11, thereby cooperating with the smoke inlet 11, reducing air volume loss and improving the overall performance of the range hood.

[0060] In some embodiments, the sidewall of the groove 31 gradually slopes towards the edge of the cover plate 30 from front to back, that is, the slope of the inner wall of the groove 31 changes slowly, which can smoothly transition with the inner bottom surface of the groove 31 and the planar part of the cover plate 30 facing the smoke collection chamber 10 without abrupt changes and sharp edges, ensuring the continuity of airflow and low resistance characteristics, which helps to reduce air volume loss, thereby ensuring wind pressure and wind speed, and avoiding noise and vibration.

[0061] It is understandable that the shape of the groove 31 is adapted to the shape of the boss 32. That is, the outer wall of the boss 32 has the characteristic of extending sloping from front to back towards the edge of the cover plate 30, so as to reduce the space occupied by the boss 32 protruding forward, thereby avoiding interference with the stove or pot and making it convenient for users to cook.

[0062] In some embodiments, the boss 32 includes at least one frustum section, such that the bottom end (the end near the smoke inlet 11) of the boss 32 has a large diameter and the top end has a small diameter. The bottom diameter of the boss 32 is 2-3 times the top diameter, in order to balance airflow efficiency and overall structural compactness. This arrangement allows the opening size of the groove 31 facing the smoke inlet 11 to be large, which can better cover the smoke inlet 11, facilitates the smooth entry of airflow into the groove 31, and increases the internal space of the groove 31, simplifying the side wall slope of the groove 31, thereby guiding the airflow direction, reducing the airflow direction gradient, and facilitating the airflow to enter the smoke inlet 11. The small top diameter of the boss 32 helps to avoid the stove and pots on the front side, providing sufficient space for the user to cook and improving the user experience.

[0063] In some embodiments, the boss 32 includes at least two frustum segments connected in sequence, with the diameter of adjacent frustum segments increasing sequentially from front to back. This arrangement allows the inclination angle between the sidewall of the frustum segment and the plane of the cover plate 30 to gradually decrease from the center to the edge of the boss 32, making the slope of the outer wall of the boss 32 and the inner wall of the groove 31 gentler, thereby reducing airflow resistance and improving the guiding effect on airflow direction.

[0064] For example, such as Figure 1 and Figure 2 As shown, the boss 32 includes three frustum segments connected in sequence, which can reduce the slope of the sidewall of the boss 32 and facilitate processing. In some other embodiments, the number of frustum segments can be set according to actual needs, and can be two, four, five or more.

[0065] Furthermore, the groove 31 and the guide structure 40 work synergistically. By guiding the airflow, the groove 31 increases the proportion of airflow entering the smoke inlet 11, increases the effective flow area of ​​the smoke inlet 11, significantly improves the air intake volume, reduces air volume loss, and helps improve the performance of the range hood. Specifically, the groove 31 increases the flow channel space between the cover plate 30 and the smoke collection chamber 10, so that the airflow entering between the cover plate 30 and the smoke collection chamber 10 first enters the groove 31, then turns before entering the smoke inlet 11.

[0066] When using a traditional flat plate as the cover, a narrow airflow space is formed between the flat plate and the smoke collection chamber 10. When the airflow flows along the direction of the flat plate to the smoke inlet, it needs to turn 90° to enter the smoke inlet. Due to space limitations and the lack of a guiding structure, the airflow is difficult to turn, resulting in a large loss of air volume. The airflow is mostly concentrated at the edge of the smoke inlet, resulting in high airflow resistance and affecting the performance of the fan. In contrast, by setting grooves 31 on the cover plate 30, the large space and smooth transition of the inner wall of the grooves 31 can better guide the airflow direction, allowing the airflow to enter the smoke inlet 11 roughly vertically with less airflow loss. This makes the effective flow area of ​​each diversion channel 1.2-1.5 times the actual cross-sectional area, increasing the wind speed and airflow. After the airflow is guided by the grooves 31, the airflow is more evenly distributed in the smoke inlet 11 and will not concentrate at the edge of the smoke inlet 11, which helps to reduce wind resistance. Combined with the flow guiding structure 40, it can effectively guide the airflow at the smoke inlet 11 to be evenly distributed, significantly weakening the flow disturbance and velocity gradient, thereby suppressing airflow separation and turbulence development, controlling the airflow velocity fluctuation range within ±5%, and the local maximum flow velocity not exceeding 1.1 times the rated flow velocity, meeting the engineering requirements of high-stability airflow organization. It is suitable for smoke collection systems with strict control requirements for airflow uniformity and flow stability.

[0067] In some embodiments, the thickness of the cover plate 30 can be 8mm-12mm, which can meet the strength requirements while controlling the cost.

[0068] In some embodiments, the telescopic drive mechanism includes a cylinder disposed in the smoke collection chamber 10. The piston rod of the cylinder is hinged to the cover plate 30, and the cylinder is communicatively connected to the fan 20 so as to control the extension and retraction of the piston rod of the cylinder according to the start and stop of the fan 20, thereby driving the cover plate 30 to move in the front-back direction.

[0069] Optionally, the cylinder can be a miniature cylinder to reduce space occupation, adapt to the smoke collection chamber 10 of the ultra-thin model, and avoid affecting the size and performance of the fan 20.

[0070] In some embodiments, two cylinders may be provided, with cylinders connected to both the left and right ends of the cover plate 30, in order to improve the stability of the movement of the cover plate 30 and prevent the cover plate 30 from tilting.

[0071] In some embodiments, the working air pressure of the cylinder is stabilized in the range of 0.4MPa-0.6MPa, and the extension and retraction speed is controlled in the range of 50mm / s-80mm / s to ensure smooth and reliable operation.

[0072] To ensure the movement accuracy of the cover plate 30, in some embodiments, the telescopic drive mechanism also includes two limit switches. The two limit switches are arranged in the front-rear direction. The limit switch located on the front side can be triggered by the cylinder when the cylinder drives the cover plate 30 to move to the second position, and the limit switch located on the rear side can be triggered by the cylinder when the cylinder drives the cover plate 30 to move to the first position. Both limit switches are communicatively connected to the cylinder so that the cylinder can start and stop in time after the cover plate 30 moves to the correct position.

[0073] It should be noted that both cylinders and limit switches are mature technologies in the field. In this invention, any existing cylinder and limit switch structure and connection relationship can be adopted, as long as the movement position of the cover plate 30 can be detected and feedback can be formed with the cylinder.

[0074] In other embodiments, the telescopic drive mechanism may also employ other drive structures besides cylinders, such as hydraulic cylinders, linear motors, lead screw and nut drive mechanisms or gear and rack drive mechanisms, without limitation.

[0075] In some embodiments, the telescopic drive mechanism further includes a fixed bracket, which includes a transverse bracket and a longitudinal bracket. The transverse bracket extends in the left-right direction and is fixed on the top inner wall of the smoke collection chamber 10. The two longitudinal brackets extend in the up-down direction and are respectively perpendicularly connected to the left and right ends of the transverse bracket. The cylinder is mounted on the longitudinal bracket to improve the fixed stability of the cylinder, thereby ensuring the stability of the movement of the cover plate 30.

[0076] Optionally, the transverse support can be fixedly connected to the top inner wall of the smoke collection chamber 10 using fasteners such as expansion bolts to ensure a firm connection; the longitudinal support and the transverse support are fixed by welding to ensure a secure fixation.

[0077] In some embodiments, the arc structure is fixed on the longitudinal support to improve the stability of the arc structure and the flow guide structure 40, improve the vibration resistance of the flow guide structure 40, and make the vibration displacement of the flow guide structure 40 less than or equal to 0.1mm. This can effectively resist the structural displacement caused by the vibration generated during the operation of the fan 20, ensure that the flow guide plate 41 is installed firmly, and ensure the stability of the flow guide effect.

[0078] In some embodiments, the mounting bracket may be made of stainless steel, which has good high temperature resistance and corrosion resistance, can adapt to long-term erosion in oil fume environments, and ensure service life.

[0079] In existing range hoods, the cover plate only has a connection point with the telescopic drive mechanism, and no connection point between the cover plate and the smoke collection chamber, resulting in unstable cover plate fixation. To solve the above problem, some embodiments combine... Figure 6 and Figure 7 As shown, a sliding guide assembly 50 is provided between the cover plate 30 and the smoke collection chamber 10 to guide the movement of the cover plate 30 and ensure the stability of the cover plate 30 when it extends and retracts in the front and rear directions.

[0080] In some embodiments, the sliding guide assembly 50 includes a first sliding guide 51 and a second sliding guide 52. The first sliding guide 51 is disposed on the side of the cover plate 30 facing the smoke collection chamber 10, and the second sliding guide 52 is disposed inside the smoke collection chamber 10. The first sliding guide 51 and the second sliding guide 52 slide in a front-back direction to improve the stability of the cover plate 30.

[0081] In some embodiments, the second sliding guide 52 is a slide rail, and the first sliding guide 51 is a slider. The slide rail extends horizontally in the front-back direction and is fixed in the smoke collection chamber 10. After the slider is embedded in the slide rail, it forms a precision sliding fit pair with the slide rail, ensuring that the cover plate 30 can extend and retract smoothly throughout the entire stroke without jamming or offset.

[0082] Optionally, the clearance between the slider and the slide rail is controlled within 0.1mm-0.3mm, which can reduce the sliding of the slider relative to the slide rail while ensuring smooth sliding, thereby improving the stability of the cover plate 30.

[0083] In some embodiments, the end of the slide rail near the cover plate 30 passes through the front wall of the smoke collection chamber 10, and the front end face of the slide rail is flush with the front side of the smoke collection chamber 10. The slider is slidably embedded in the slide rail, which not only achieves sliding engagement with the slide rail, but also ensures that the cover plate 30 is in close contact with the front side of the smoke collection chamber 10 in the first position, reducing the gap between the cover plate 30 and the smoke collection chamber 10, thereby reducing the overall size of the range hood. In other embodiments, the first sliding guide 51 is a slide rail, and the second sliding guide 52 is a slider, which can also achieve sliding guidance.

[0084] In other embodiments, the sliding guide assembly 50 may also adopt other sliding fit forms, such as guide sleeve and guide rod or slider and guide groove, etc., which are not limited here.

[0085] This invention improves the strength of the cover plate 30 by setting a boss 32 on the cover plate 30 and adds a sliding guide component 50 to improve the stability of the cover plate 30 during movement, optimizing the structural characteristics and expansion and contraction stability of the cover plate 30. This solves the problems of insufficient strength, easy deformation, unstable fixation, and easy sagging during extension of the traditional cover plate 30, which leads to poor expansion and contraction. By setting a flow guiding structure 40, an arc guide surface 221 and a groove 31 in synergy, the airflow guiding path is optimized. Without increasing the thickness of the smoke collection chamber 10, the effective flow area of ​​the smoke inlet 11 is effectively increased and the fan inlet loss is reduced. This ensures that the range hood meets the rated operating requirements. It solves the defects of traditional range hoods that are limited by the thickness of the smoke collection chamber and have insufficient flow area and fan inlet loss due to unreasonable cover plate movement. This becomes the core breakthrough in solving the fan performance problem.

[0086] To demonstrate the performance improvement of the range hood of the present invention, an embodiment and a comparative example are provided, and experimental verification is conducted on the embodiment and the comparative example. Specifically, the range hoods in the embodiment and the comparative example both adopt an ultra-thin smoke collection chamber 10 and are equipped with a cover plate 30 that can extend and retract. The difference is that the embodiment adopts the aforementioned arc structure, a cover plate 30 with a boss 32 and a groove 31, and a flow guiding structure 40, while the comparative example has a flat cover plate structure, and the smoke inlet 11 does not have an arc structure and a flow guiding structure 40. Other structures and dimensions of the embodiment and the comparative example are the same. The experimental data of the comparative example are shown in Table 1, and the comparative data of the embodiment are shown in Table 2. As shown in Tables 1 and 2, this invention conducted experiments and data comparisons for three operating conditions: maximum air volume, shut-off air volume, and rated operating air volume. The air volume and fan speed are the same in both the comparative example and the embodiment under these three conditions. Maximum air volume refers to the maximum air volume that the range hood can discharge per minute when there is no resistance at the exhaust vent. Shut-off air volume is the air volume inside the range hood when the exhaust vent is completely blocked. Rated operating air volume refers to the actual air volume that the range hood can discharge after overcoming certain resistance from the common flue, exhaust pipe, check valve, etc.

[0087] In the experiment, static pressure, total pressure, shaft power, and total pressure efficiency were obtained for the examples and comparative examples under three operating conditions. Static pressure refers to the static pressure generated in the duct after the range hood overcomes the duct resistance, which is the actual pressure when the range hood exhausts smoke. The higher the static pressure, the smoother the smoke exhaust in the common flue and the stronger the resistance to backdraft. Total pressure is the combination of static pressure and dynamic pressure, which is the total energy of the range hood's smoke exhaust capacity and is used to accurately calculate the fan performance. Shaft power is the actual power transmitted from the motor to the impeller, which is also the actual energy consumed to drive the impeller to rotate. It determines the energy consumption level of the range hood. Generally, the higher the air volume and static pressure, the higher the required shaft power. Total pressure efficiency is the ratio of output power (i.e., the product of air volume and air pressure) to input power (i.e., shaft power). It is a core indicator for measuring technical level and energy efficiency. The higher the value, the better the smoke exhaust effect with less electricity.

[0088] A comparison of Tables 1 and 2 shows that the embodiment, employing the aforementioned arc structure, the cover plate 30 with bosses 32 and grooves 31, and the flow guiding structure 40, improves the flow conditions at the smoke inlet 11. Compared to the comparative example, it effectively suppresses flow separation, optimizes the pressure gradient, and improves the aerodynamics of the fan 20 at its rated operating airflow by 3.6%. Simultaneously, the system's pressure generation capability is significantly enhanced, resulting in a substantial increase in static pressure and total pressure. Furthermore, the vortex scale and turbulence capacity of the flow channel are significantly reduced, increasing the maximum outlet static pressure by 168.8 Pa. This results in better exhaust capacity and stronger anti-backdraft capability for the range hood. The shaft power is reduced under maximum and rated operating airflow conditions, leading to lower energy consumption and a significant improvement in total pressure efficiency. This results in better smoke extraction while maintaining energy efficiency, significantly enhancing the performance and competitiveness of the range hood. In addition, the overall structural optimization expands the stable operating range of the fan 20, further increasing its maximum volumetric flow capacity.

[0089] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A range hood, characterized in that, include: Smoke collection chamber (10), with a smoke inlet (11) provided on the front side of the smoke collection chamber (10); A fan (20) is installed inside the smoke collection chamber (10); A cover plate (30) is movably disposed on the front side of the smoke collection chamber (10). The cover plate (30) can slide relative to the smoke collection chamber (10) in the front-back direction to switch between a first position that fits against the front side of the smoke collection chamber (10) and a second position that is spaced apart from the front side of the smoke collection chamber (10). A flow guiding structure (40) is provided at the smoke inlet (11) to divide the smoke inlet (11) into multiple flow channels to ensure uniform airflow.

2. The range hood according to claim 1, characterized in that, The flow guiding structure (40) includes multiple flow guiding plates (41), which are arranged crosswise within the smoke inlet (11) to divide the smoke inlet (11) into multiple flow channels.

3. The range hood according to claim 2, characterized in that, The middle parts of the multiple guide plates (41) intersect and radiate outwards, the center of the guide plate (41) coincides with the center of the smoke inlet (11), and the included angle between any two adjacent guide plates (41) is equal.

4. The range hood according to claim 3, characterized in that, The smoke inlet (11) is circular, and the guide plate (41) extends radially along the smoke inlet (11); And / or, the flow guiding structure (40) further includes an annular support (42) which is cross-connected to each of the flow guiding plates (41).

5. The range hood according to any one of claims 1-4, characterized in that, An arc structure is provided at the smoke inlet (11), the arc structure includes an arc guide surface (221) protruding towards the inside of the smoke inlet (11), and the flow guiding structure (40) is connected to the arc guide surface (221).

6. The range hood according to claim 5, characterized in that, The radius of curvature of the arc guide surface (221) is 15mm-25mm.

7. The range hood according to claim 5, characterized in that, The fan (20) includes a housing (22), on which an air inlet communicating with the smoke inlet (11) is provided. The edge of the housing (22) surrounding the air inlet bends and extends inward toward the smoke inlet (11) to form the arc structure. The arc guide surface (221) abuts against the edge of the smoke collection chamber (10) surrounding the smoke inlet (11).

8. The range hood according to claim 5, characterized in that, The fan (20) includes an impeller (21), and an annular flange (211) is provided at one axial end of the impeller (21) along the circumference of the smoke inlet (11). The arc guide surface (221) extends into the annular flange (211) and is spaced apart from the annular flange (211) to form a sealing gap (12).

9. The range hood according to claim 8, characterized in that, The sealing gap (12) is 0.5mm-2mm.

10. The range hood according to any one of claims 1-4, characterized in that, The cover plate (30) is recessed on the side facing the smoke inlet (11) to form a groove (31), and a boss (32) is formed on the side of the cover plate (30) away from the smoke inlet (11). The projection of the groove (31) on the smoke collection chamber (10) in the front-back direction covers at least part of the smoke inlet (11).

11. The range hood according to claim 10, characterized in that, The sidewall of the groove (31) gradually extends towards the edge of the cover plate (30) from front to back; And / or, the depth of the groove (31) is 10mm-20mm; And / or, the radial dimension of the groove (31) is 1.5-2 times the radial dimension of the smoke inlet (11); And / or, the boss (32) includes at least two frustum segments connected in sequence, the diameter of two adjacent frustum segments increasing from front to back, and the diameter of the boss (32) at one end near the smoke inlet (11) along the axial direction is 2-3 times the diameter of the other end along the axial direction.

12. The range hood according to any one of claims 1-4, characterized in that, The cover plate (30) is provided with a first sliding guide (51), and the smoke collection chamber (10) is provided with a second sliding guide (52). The first sliding guide (51) and the second sliding guide (52) slide together in the front-back direction.

Images