Low-noise air intake system and integrated cooker

Abstract

The application discloses a low-noise air inlet system, which comprises an air inlet channel and a fan box in communication with the air inlet channel, wherein a fan assembly is arranged in the fan box, the fan assembly operates to generate negative pressure so that oil fume enters the fan box through the air inlet channel, the air inlet channel comprises a guide section and a connecting section, the connecting section gradually decreases in cross-sectional area in a direction away from the guide section, and the bottom end of the connecting section is connected with the fan box, the fan box comprises a top plate, the connecting section is connected with the fan box through the top plate, and the top plate is arranged in an inclined mode and forms a wing-shaped structure with a middle low and two sides high. Compared with the prior art, the technical scheme provided by the application has the following advantages: turbulence and turbulent flow are reduced, and the noise reduction effect is remarkable.

Description

Technical Field

[0001] This invention relates to an air intake system for integrated cooktops, and more particularly to a low-noise air intake system and an integrated cooktop. Background Technology

[0002] Currently, most integrated stoves on the market use long and narrow air intake ducts and short and wide fan boxes for their air intake systems. However, both the air intake ducts and fan boxes are almost always in a conventional cuboid shape, which inevitably leads to turbulence and chaotic flow, resulting in increased noise in the air intake system and affecting the user experience.

[0003] Therefore, many manufacturers have attempted to reduce noise by improving the air intake system. For example, Chinese invention application CN114970400A, entitled "A Novel Down-Mounted Integrated Stove Cabinet," discloses a cabinet body and a fan section. The cabinet body has an inlet at its upper end and an outlet at its lower right end. The fan section is fixedly connected to the outer end of the outlet. An inclined section is connected to the lower right end of the inlet, and an inclined section is provided to the lower left end of the cabinet body, connecting to the outlet. While this invention can reduce noise, the design of "one side inclined, the other side arc-shaped connection to the outlet" can easily cause the airflow congested on the right side of the cabinet body and moving along the inclined section to conflict with the airflow moving along the arc surface on the left side of the cabinet, resulting in severe turbulence and affecting the smoke extraction effect.

[0004] For example, Chinese utility model patent CN208750796U, entitled "Integrated Stove for Easy Underfloor Heating Adjustment," discloses a design including a cabinet 1, with a horizontally fixed air duct system 4 inside the cabinet 1. The bottom end of the air duct housing 5 is provided with a first inclined guide portion 16 to save space at the rear of the cabinet 1. This utility model's technical solution improves the bottom end of the air duct housing 5 to save space by tilting the guide portion 16. However, due to this "front end" and "rear end" arrangement of the air duct housing 5, the airflow needs to be redirected to enter the front end and exit through the air outlet interface 8, inevitably leading to poor smoke extraction.

[0005] For example, the Chinese utility model patent with authorization announcement number CN209910010U, entitled "An Integrated Stove with Large Air Volume and Silent Air Duct", discloses that: a sound-absorbing component is provided in the air box (8), the sound-absorbing component includes a sound-absorbing panel (13) that is inclined and symmetrically distributed with the inlet in the volute component (9), and a sound-absorbing cavity is formed between the sound-absorbing panel (13) and the air box (8). The technical solution of this utility model only forms a sound-absorbing component in a single non-critical part, and there is no corresponding structural setting in the position where the noise is the greatest. Therefore, it cannot significantly reduce the noise.

[0006] Finally, Chinese utility model patent CN218269228U, entitled "Integrated Stove Air Duct System and Integrated Stove Having the Same," discloses that the air duct assembly 200 may include an air inlet section 210, an air outlet section 230, and a connector 220. The connector 220 can connect the air inlet section 210 and the air outlet section 230. The air outlet 231 can be disposed on the air outlet section 230, and the air inlet 211 can be disposed on the air inlet section 210. The width of the air inlet section 210 is greater than the width of the air outlet section 230, and the connector 220 has a gradually narrowing width along the direction from the air inlet section 210 to the air outlet section 230. Although the gradually narrowing connector 220 reduces turbulence and chaotic flow to some extent, this utility model does not make corresponding improvements in noise reduction of the air box assembly 100. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a low-noise air intake system and integrated stove that significantly reduces turbulence and noise.

[0008] The present invention mainly adopts the following technical solution:

[0009] A low-noise air intake system includes an air intake duct and a fan box connected to the air intake duct. A fan assembly is installed inside the fan box. The fan assembly generates negative pressure when it operates, causing oil fumes to enter the fan box through the air intake duct. The air intake duct includes a guide section and a connecting section. The cross-sectional area of ​​the connecting section gradually decreases in the direction away from the guide section, and the bottom end of the connecting section is connected to the fan box. The fan box includes a top plate, and the connecting section is connected to the fan box through the top plate. The top plate is inclined and forms an airfoil structure that is low in the middle and high on both sides.

[0010] The guide section is rectangular, and the connecting section has at least its left and / or right sidewalls formed as inclined guide plates. The length of the guide section is a, and the maximum length of the bottom end of the connecting section is bmax, wherein 0.65≤bmax / a≤0.85.

[0011] The guide section is rectangular, the front and rear sidewalls of the connecting section are parallel, and the left and right sidewalls of the connecting section form guide plates inclined along the plane. The angles between the guide plates and the horizontal direction along the width of the connecting section are the same or different. When the angles between the guide plates and the horizontal direction along the width of the connecting section are the same, the angle between the guide plate on the left side of the connecting section and the horizontal direction is αL, and the corresponding elevation is hL; the angle between the guide plate on the right side of the connecting section and the horizontal direction is αR, and the corresponding elevation is hR. Here, a = bmax + hL / tanαL + hR / tanαR, and the values ​​of αL and αR are between 10° and 80°.

[0012] Where αL=αR=α, and hL=hR=H.

[0013] The guide plate is made of microporous plate or mesh plate, and a sound-absorbing layer is laid on the outer surface of the guide plate.

[0014] The guide plate is made of microporous plate or mesh plate, and a sound-absorbing layer is laid on the outer surface of the guide plate.

[0015] Wherein, the width of the guide section and the width of the connecting section are both c, and the width of the fan box is d, where 0.3≤c / d≤0.5, and d=c+H / tanα.

[0016] The top plate has a flush edge on the side that connects to the bottom of the connecting section, and the top plate forms an airfoil-shaped undulating edge that is low in the middle and high on both sides on the side away from the bottom of the connecting section. The top plate includes a middle part and outer wings located at both ends of the middle part, or the top plate includes a middle part, outer wings located at both ends of the middle part, and a transition part connecting the middle part and the outer wings. The angle between the middle part and the horizontal direction is βM, and the angle between the outer wings and the horizontal direction is βp, wherein βM > βp and 3° ≤ βM - βp ≤ 10°.

[0017] The angle βM between the middle part and the horizontal direction is 25°, and the minimum value of the angle βp between the outer wing and the horizontal direction is 20°.

[0018] Wherein, the maximum length of the fan box is fmax. When the side of the middle part that connects to the connecting section has the same size as the side of the middle part that is away from the bottom of the connecting section, the length of the middle part in the length direction of the fan box is K, where 0.5≤K / fmax≤0.7.

[0019] A reinforcing plate is also provided between the bottom end of the connecting section and the top plate.

[0020] The top plate is made of microporous plate or grid plate, and a sound-absorbing layer is laid on the outer surface of the top plate.

[0021] An integrated stove that uses the aforementioned low-noise air intake system.

[0022] According to the technical solution described in this invention, the following beneficial effects are achieved: the bottom end of the air inlet duct connecting section is connected to the fan box, and the top plate of the fan box is inclined and forms an airfoil structure that is low in the middle and high on both sides. This not only avoids path conflicts and airflow energy loss caused by airflow turning, thus improving the smoke extraction effect, but also avoids turbulence and chaotic flow caused by the sudden widening of the airflow path when entering the fan box from the air inlet duct, thereby significantly reducing noise. In addition, the inclined top plate also utilizes the Coanda effect and fluid viscosity principle to better guide the airflow, thereby uniformly introducing the airflow into the fan assembly. The shape of the top plate, which is low in the middle and high on both sides, is conducive to accelerating the airflow on both sides and speeding up the airflow at the edge position. The cross-sectional area of ​​the connecting section gradually decreases and the airflow is guided by the guide plate, which not only does not reduce the airflow velocity but also avoids the generation of undesirable eddies. The sound-absorbing layer can further absorb sound. CFD simulation test shows that a noise reduction effect of 8dB can be achieved. Attached Figure Description

[0023] Figure 1 This is a front view structural diagram of an air intake system in the prior art.

[0024] Figure 2 for Figure 1 Schematic diagram of the side structure of the central air intake system.

[0025] Figure 3 The image shows the CFD simulation test results of the air intake system in the existing technology, with three areas highlighted in darker color (noise level as high as 91dB).

[0026] Figure 4 This is a schematic diagram of the air intake system structure in this application.

[0027] Figure 5 This is a front view structural diagram of the air intake system in this application.

[0028] Figure 6 for Figure 4 Schematic diagram of the side structure of the central air intake system.

[0029] Figure 7 for Figure 4 A schematic diagram of the structure after the outer surface of the air intake system's guide plate is covered with a sound-absorbing layer.

[0030] Figure 8 for Figure 4 A schematic diagram of the structure after the sound-absorbing layer is laid on the outer surface of the top plate of the central air intake system.

[0031] Figure 9 The image shows the CFD simulation test results of the air intake system in this application, with three color transitions marked (noise level is only 83dB).

[0032] Figure 10 This is a schematic diagram of the top slab structure.

[0033] Figure 11 This is a schematic diagram of the structure when a microporous plate is used for the top plate.

[0034] 1. Air inlet duct, 11. Guide section, 12. Connecting section, 2. Fan box, 21. Top plate, 211. Middle section, 212. Outer wing section, 3. Fan assembly, 4. Guide plate, 5. Reinforcing plate, 6. Sound absorption layer. Detailed Implementation

[0035] The invention will be further described below with reference to the accompanying drawings:

[0036] See Figure 4-11 As shown, a low-noise air intake system includes an air intake duct 1 and a fan housing 2 connected to the air intake duct 1. A fan assembly 3 is installed inside the fan housing 2. The operation of the fan assembly 3 generates negative pressure, allowing oil fumes to enter the fan housing 2 through the air intake duct 1. The air intake duct 1 includes a guide section 11 and a connecting section 12. The cross-sectional area of ​​the connecting section 12 gradually decreases in the direction away from the guide section 11, and the bottom end of the connecting section 12 connects to the fan housing 2. The fan housing 2 includes a top plate 21, and the connecting section 12 connects to the fan housing 2 through the top plate 21. The top plate 21 is inclined and forms an airfoil structure that is low in the middle and high on both sides. In this application, "low" and "high" in "low in the middle and high on both sides of the top plate" specifically refer to the comparison between the two and are not a definition of technical features. Preferably, to adapt to the internal structure of the integrated stove, the connecting section 12 is generally a flat channel. Therefore, the cross-sectional area of ​​the connecting section 12 gradually decreases. It can be that the left and / or right sides of the connecting section 12 form a "shoulder-shaped" structure, or the connecting section 12 as a whole forms a "bucket-shaped" structure. More preferably, the gradual decrease in the cross-sectional area of ​​the connecting section 12 includes, but is not limited to, the sidewalls of the connecting section 12 being inclined and recessed along a plane, or inclined and recessed along an arc surface. This structural design can avoid path conflicts and airflow energy loss caused by airflow turning, improve the smoke exhaust effect, and also avoid turbulence and chaotic flow caused by the sudden widening of the airflow path when entering the fan box from the air inlet duct, thereby significantly reducing noise. In addition, the inclined top plate also utilizes the Coanda effect and fluid viscosity principle to better guide the airflow, thereby uniformly introducing the airflow into the fan assembly and avoiding vibration of the fan assembly due to uneven airflow. The shape of the top plate being low in the middle and high on both sides is conducive to accelerating the airflow on both sides, speeding up the airflow flow at the edge position, and avoiding airflow congestion.

[0037] See Figure 4-8As shown, the guide section 11 is a cuboid, and the connecting section 12 has at least its left and / or right sidewalls formed as inclined guide plates 4. The length of the guide section 11 is 'a', and the maximum length of the bottom end of the connecting section 12 is 'bmax', where 0.65 ≤ bmax / a ≤ 0.85. Preferably, in actual production and use, setting the length 'a' of the guide section 11 to 830 mm and the maximum length 'bmax' of the bottom end of the connecting section 12 to 596 mm is a common practice. Preferably, the connecting section 12 can be an inverted trapezoid. Preferably, the "inclined setting" in this application includes, but is not limited to, inclination along a plane or inclination along an arc surface.

[0038] See Figure 4-8 As shown, the guide section 11 is a cuboid. The front and rear sidewalls of the connecting section 12 are arranged in parallel, and the left and right sidewalls of the connecting section 12 form guide plates 4 that are inclined along the plane. The angle between the guide plates 4 and the horizontal direction along the width direction of the connecting section 12 is the same or different. When the angle between the guide plates 4 and the horizontal direction along the width direction of the connecting section 12 is the same, the angle between the guide plates 4 on the left side of the connecting section 12 and the horizontal direction is αL, and the corresponding elevation is hL; the angle between the guide plates 4 on the right side of the connecting section 12 and the horizontal direction is αR, and the corresponding elevation is hR. Where a = bmax + hL / tanαL + hR / tanαR, and the values ​​of αL and αR are between 10° and 80° respectively. In this application, preferably, including but not limited to, the connecting section 12 is vertically mounted on the fan box 2 or tilted at a certain angle on the fan box 2. When the connecting section 12 is vertically mounted on the fan box 2, the aforementioned "elevation" refers to the distance from the point where the outermost edge of the guide plate 4 is located to the plane where the bottom end of the connecting section 12 is located; when the connecting section 12 is tilted on the fan box 2, the aforementioned "elevation" refers to the distance from the center point of the outermost edge of the guide plate 4 to the plane where the bottom end of the connecting section 12 is located. Preferably, the values ​​of αL and αR are both 30°. According to Bernoulli's principle, when fluid enters a channel with a sudden change in cross-sectional area (expansion or contraction), it will inevitably cause a decrease or increase in static pressure, resulting in flow loss, turbulence, and backflow. By adding a guide plate, based on the Coanda effect and the principle of fluid viscosity, the turbulence and backflow phenomena can be greatly mitigated, thereby reducing vibration and noise.

[0039] Furthermore, αL = αR = α, and hL = hR = H.

[0040] See Figure 7 As shown, the guide plate 4 is a microporous plate or a mesh plate, and a sound-absorbing layer 6 is laid on the outer surface of the guide plate 4. Preferably, the sound-absorbing layer 6 is made of sound-absorbing cotton, and the shape of the sound-absorbing layer 6 is used to fill the outline of the air inlet duct 1 that is missing compared with the prior art due to the setting of the guide plate 4.

[0041] See Figure 7 As shown, the guide plate 4 is a microporous plate or a mesh plate, and a sound-absorbing layer 6 is laid on the outer surface of the guide plate 4. Preferably, the sound-absorbing layer 6 is made of sound-absorbing cotton, and the shape of the sound-absorbing layer 6 is used to fill the outline of the air inlet duct 1 that is missing compared with the prior art due to the setting of the guide plate 4.

[0042] See Figure 6 As shown, the width of the guide section 11 is equal to the width of the connecting section 12, both being c, and the width of the fan box 2 is d, where 0.3 ≤ c / d ≤ 0.5, and d = c + H / tanα. In this application, when the connecting section 12 is tilted at a certain angle and assembled on the fan box 2, the width d of the fan box 2 will be larger than the actual value. This is mainly because the tilted connecting section 12 is still calculated using the aforementioned α, H, etc. However, since the area occupied by the bottom end of the connecting section 12 on the top plate 21 also increases accordingly after tilting, this technical solution is also applicable to actual scenarios. Preferably, in actual production and use, setting the width c of the connecting section 12 to 90mm and the width d of the fan box to 215mm is a relatively common practice. This structural design creates a specific relationship between the top plate size and the tilt angle of the guide plate, making a significant contribution to noise reduction. CFD simulation tests show that it can achieve a noise reduction effect of 8dB, which is comparable to... Figure 1-3 The noise simulation test results shown in the prior art have completely different technical effects.

[0043] See Figure 4 , 6 As shown in Figures 8, 10, and 11, the top plate 21 has a flush edge on the side where it connects to the bottom of the connecting section 12, and an airfoil-shaped undulating edge that is lower in the middle and higher at both sides on the side away from the bottom of the connecting section 12. The top plate 21 includes a middle portion 211 and outer wing portions 212 located at both ends of the middle portion 211, or the top plate 21 includes a middle portion 211, outer wing portions 212 located at both ends of the middle portion 211, and a transition portion connecting the middle portion 211 and the outer wing portions 212. The angle between the middle portion 211 and the horizontal direction is βM, and the angle between the outer wing portions 212 and the horizontal direction is βp, wherein βM > βp and 3° ≤ βM - βp ≤ 10°. This structural design plays an important role in noise reduction and airflow guidance. Preferably, the maximum length bmax of the bottom of the connecting section 12 is equal to the maximum length fmax of the fan box 2. Furthermore, this application does not exclude the possibility that the maximum length bmax of the bottom end of the connecting section 12 is less than the maximum length fmax of the fan box 2, that is, the connecting section 12 is inserted into the center of the top plate 21, or the connecting section 12 is inserted into the center of the top plate 21 and is flush with one side edge of the top plate 21. In this case, the edges of the top plate 21 relative to the bottom end of the connecting section 12 in four radial directions (or three radial directions) all form such airfoil undulation edges.

[0044] See Figure 4 , 7 As shown, the angle βM between the middle part 211 and the horizontal direction is 25°, and the minimum value of the angle βp between the outer wing part 212 and the horizontal direction is 20°.

[0045] See Figure 5 As shown, the maximum length of the fan box 2 is fmax. When the side of the middle part 211 that connects with the connecting section 12 has the same size as the side of the middle part 211 that is away from the bottom of the connecting section 12, the length of the middle part in the length direction of the fan box 2 is K, where 0.5≤K / fmax≤0.7.

[0046] See Figure 5 , 10 As shown in Figure 11, a reinforcing plate 5 is also provided between the bottom end of the connecting section 12 and the top plate 21. This structural design helps to strengthen the mechanical strength of the connection between the air inlet duct and the fan box, and reduces vibration caused by noise.

[0047] See Figure 8 , 11 As shown, the top plate 21 is made of a perforated plate or a mesh plate, and a sound-absorbing layer 6 is laid on the outer surface of the top plate 21. Preferably, the sound-absorbing layer 6 is made of sound-absorbing cotton, and the shape of the sound-absorbing layer 6 is used to fill the outline of the fan box 2 that is missing compared with the prior art due to the installation of the top plate 21.

[0048] An integrated stove that uses the aforementioned low-noise air intake system.

[0049] Although the specific embodiments of the technical solutions described in this invention have been described above, those skilled in the art can make modifications to them without departing from the spirit and principles of this application. The scope of protection of this invention is defined by its claims and their equivalents.

Claims

1. A low-noise air intake system, comprising an air intake duct and a fan box connected to the air intake duct, wherein a fan assembly is disposed inside the fan box, and the fan assembly generates negative pressure during operation to allow oil fumes to enter the fan box through the air intake duct, characterized in that: The air inlet duct includes a guide section and a connecting section. The cross-sectional area of ​​the connecting section gradually decreases in the direction away from the guide section, and the bottom end of the connecting section is connected to the fan box. The fan box includes a top plate, and the connecting section is connected to the fan box through the top plate. The top plate is inclined and forms an airfoil structure that is low in the middle and high on both sides. The guide section is cuboid, and at least the left and / or right sidewalls of the connecting section are formed as inclined guide plates. The length of the guide section is 'a', and the maximum length of the bottom end of the connecting section is 'bmax', where 0.65 ≤ bmax / a ≤ 0.

85. The guide section is cuboid, and the front and rear sides of the connecting section... The sidewalls of the connecting section are arranged in parallel, and the left and right sidewalls of the connecting section form guide plates that are inclined along the plane. The angles between the guide plates and the horizontal direction along the width of the connecting section are the same or different. When the angles between the guide plates and the horizontal direction along the width of the connecting section are the same, the angle between the guide plate on the left side of the connecting section and the horizontal direction is αL, and the corresponding elevation is hL; the angle between the guide plate on the right side of the connecting section and the horizontal direction is αR, and the corresponding elevation is hR. Where a = bmax + hL / tanαL + hR / tanαR, and the values ​​of αL and αR are between 10° and 80°.

2. The low-noise air intake system according to claim 1, characterized in that: αL=αR=α, and hL=hR=H.

3. The low-noise air intake system according to claim 1, characterized in that: The guide plate is made of microporous plate or mesh plate, and a sound-absorbing layer is laid on the outer surface of the guide plate.

4. The low-noise air intake system according to claim 2, characterized in that: The width of the guide section is equal to the width of the connecting section, both being c, and the width of the fan box is d, where 0.3≤c / d≤0.5, and d=c+H / tanα.

5. The low-noise air intake system according to claim 4, characterized in that: The top plate has a flush edge on the side that connects to the bottom of the connecting section, and the top plate forms an airfoil-shaped undulating edge that is low in the middle and high on both sides on the side away from the bottom of the connecting section. The top plate includes a middle part and outer wings located at both ends of the middle part, or the top plate includes a middle part, outer wings located at both ends of the middle part, and a transition part connecting the middle part and the outer wings. The angle between the middle part and the horizontal direction is βM, and the angle between the outer wings and the horizontal direction is βp, wherein βM > βp and 3° ≤ βM - βp ≤ 10°.

6. The low-noise air intake system according to claim 5, characterized in that: The angle βM between the middle part and the horizontal direction is 25°, and the minimum value of the angle βp between the outer wing and the horizontal direction is 20°.

7. The low-noise air intake system according to claim 5 or 6, characterized in that: The maximum length of the fan box is fmax. When the side of the middle part that connects to the connecting section has the same size as the side of the middle part that is away from the bottom of the connecting section, the length of the middle part in the length direction of the fan box is K, where 0.5≤K / fmax≤0.

7.

8. The low-noise air intake system according to any one of claims 1, 2 to 6, characterized in that: A reinforcing plate is also provided between the bottom end of the connecting section and the top plate.

9. The low-noise air intake system according to any one of claims 1, 2 to 6, characterized in that: The top plate is made of microporous plate or grid plate, and a sound-absorbing layer is laid on the outer surface of the top plate.

10. An integrated stove, characterized in that: Use the low-noise air intake system as described in any one of claims 1 to 9.

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