Variable-diameter perforated volute, centrifugal fan and range hood
By setting perforated and sound-absorbing components with gradually varying apertures on the volute ring wall, the problem of poor noise reduction effect in the volute design is solved, achieving a better balance between noise reduction and airflow performance.
Patent Information
- Application Number
- CN202520457850.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-03-14
AI Technical Summary
Existing volute perforation designs ignore the airflow state inside the volute, resulting in limited noise reduction effect. Furthermore, most volute perforation schemes use a uniform arrangement of a single aperture, which leads to poor noise reduction performance.
It adopts a variable diameter perforated volute design, with multiple perforations of gradually varying diameters on the volute ring wall to match the non-uniformly distributed airflow inside the volute, combined with sound-absorbing components to improve the noise reduction effect.
While maintaining airflow performance, it achieves better noise reduction effect and improves the overall structural stability and noise reduction performance of the volute.
Smart Images
Figure CN223724943U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of fan technology, and in particular to a variable diameter perforated volute, a centrifugal fan, and a range hood. Background Technology
[0002] The core power system of range hoods generally uses a centrifugal fan system, and the volute, as the core component of the fan system, directly affects the noise and airflow performance of the range hood. The noise of a range hood during operation is mainly generated by the separation and impact of airflow on the high-speed rotating impeller and the volute. Currently, the optimization of the volute mainly focuses on its shape and profile design.
[0003] Although some noise reduction solutions involve creating several noise-reducing holes in the volute, existing volute noise reduction measures are still relatively poor. Volute perforation solutions are limited to straight hole designs, resulting in poor noise reduction performance. For example, volute perforation solutions using a uniform aperture array design only involve the perforation diameter, perforation spacing, and perforation rate of the volute annular wall. Typically, a single aperture size and perforation spacing are determined while ensuring a certain perforation rate, and noise-reducing sound-absorbing cotton is used on the outside of the volute to guarantee the noise reduction level.
[0004] However, the airflow distribution in the volute is highly uneven, and the velocity distribution in areas such as the volute tongue ring wall also varies greatly. Uniform arrangement takes more into consideration for processing convenience and ignores the airflow state inside the volute, resulting in limited actual noise reduction effect. Utility Model Content
[0005] Based on this, it is necessary to address the problem that the volute perforation scheme using a uniform aperture array design has limited actual noise reduction effect due to neglecting the airflow state inside the volute. This application provides a variable diameter perforated volute, a centrifugal fan, and a range hood, which can achieve better noise reduction effect while taking into account air volume performance.
[0006] According to one aspect of this application, one embodiment provides a variable-diameter perforated volute, comprising:
[0007] Front cover with air inlet;
[0008] The rear cover plate is arranged at a distance from the front cover plate;
[0009] A volute annular wall, wherein the volute annular wall is disposed between the front cover plate and the rear cover plate to form an air outlet communicating with the air inlet, and the volute annular wall has multiple perforations with gradually changing diameters; and
[0010] The sound-absorbing component is disposed on the outside of the volute ring wall and covers the perforation.
[0011] In some embodiments of the present application, the hole diameter of the perforation gradually changes along the circumferential direction and / or the axial direction of the volute ring wall.
[0012] In some embodiments of the present application, the volute ring wall comprises a volute tongue section, an outlet section arranged in spaced relation to the volute tongue section to form the air outlet, and a ring wall section extending from the volute tongue section to the outlet section in a curved manner; the hole diameter of the perforation gradually increases or gradually decreases along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section.
[0013] In some embodiments of the present application, the hole diameter of the perforation is between 0 mm and 8 mm, and the circumferential hole diameter variation rate of the perforation is between 0 and 20%.
[0014] In some embodiments of the present application, the hole spacing of the perforation gradually increases or gradually decreases along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section; the hole spacing of the perforation is between 0 mm and 10 mm, and the circumferential hole spacing variation rate of the perforation is between 0 and 10%.
[0015] In some embodiments of the present application, the volute ring wall comprises a volute tongue section, an outlet section arranged in spaced relation to the volute tongue section to form the air outlet, and a ring wall section extending from the volute tongue section to the outlet section in a curved manner; the hole diameter of the perforation gradually increases first and then gradually decreases or gradually decreases first and then gradually increases along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section.
[0016] In some embodiments of the present application, the hole diameter of the perforation gradually decreases or gradually increases along the axial direction of the volute ring wall from front to back; the hole spacing of the perforation is between 0 mm and 8 mm, and the axial hole diameter variation rate of the perforation is between 0 and 30%.
[0017] In some embodiments of the present application, the axial hole spacing of the perforation gradually decreases or gradually increases along the axial direction of the volute ring wall from front to back; the axial hole spacing of the perforation is between 0 mm and 10 mm, and the axial hole spacing variation rate of the perforation is between 0 and 20%.
[0018] In some embodiments of the present application, the perforation is a dimple perforation or a through hole penetrating through the volute ring wall; the perforation is arranged in an array or a staggered array on the volute ring wall; the perforation is formed in a segmented region arranged in spaced relation on the volute ring wall.
[0019] According to another aspect of the present application, one embodiment of the present application further provides a centrifugal fan, comprising:
[0020] The variable-diameter perforated volute described above; and
[0021] an impeller rotatably arranged in the variable-pore perforated volute.
[0022] According to another aspect of the present application, one embodiment of the present application further provides a range hood, comprising:
[0023] a range hood cabinet; and
[0024] The centrifugal fan is arranged in the range hood cabinet.
[0025] In summary, compared with the perforated volute with a single pore diameter, the variable-pore perforated volute of the present application is provided with the pore-diameter-gradually-changing perforations on the volute ring wall to match the non-uniformly distributed airflow in the volute, which is beneficial to the wind volume performance and noise reduction effect. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 Structure schematic diagram of a range hood according to one embodiment of the present application;
[0027] Figure 2 A perspective schematic diagram of a variable-pore perforated volute in a range hood according to the above embodiment of the present application is shown;
[0028] Figure 3 An exploded schematic diagram of a variable-pore perforated volute according to the above embodiment of the present application is shown;
[0029] Figure 4 A first example of a volute ring wall in a variable-pore perforated volute according to the above embodiment of the present application is shown;
[0030] Figure 5 A top view schematic diagram of the volute ring wall according to the above first example of the present application is shown;
[0031] Figure 6 A perspective schematic diagram of Figure 5 A-A sectional view schematic diagram of the volute ring wall shown;
[0032] Figure 7 A second example of a volute ring wall in a variable-pore perforated volute according to the above embodiment of the present application is shown;
[0033] Figure 8 A third example of a volute ring wall in a variable-pore perforated volute according to the above embodiment of the present application is shown;
[0034] Figure 9 A perspective schematic diagram of Figure 8 B-B sectional view schematic diagram of the volute ring wall shown;
[0035] Figure 10 A fourth example of a volute ring wall in a variable-pore perforated volute according to the above embodiment of the present application is shown;
[0036] Figure 11 A C-C sectional view of the volute ring wall is shown. Figure 10 A C-C sectional view of the volute ring wall is shown.
[0037] Figure 12 A first deformation example of the volute ring wall in the variable-diameter perforated volute according to the above embodiment of the present application is shown.
[0038] Figure 13 A second deformation example of the volute ring wall in the variable-diameter perforated volute according to the above embodiment of the present application is shown.
[0039] Figure 14 A third deformation example of the volute ring wall in the variable-diameter perforated volute according to the above embodiment of the present application is shown.
[0040] Figure 15 A fourth deformation example of the volute ring wall in the variable-diameter perforated volute according to the above embodiment of the present application is shown.
[0041] Figure 16 A fifth deformation example of the volute ring wall in the variable-diameter perforated volute according to the above embodiment of the present application is shown.
[0042] Main element symbol explanation:
[0043] 1, variable-diameter perforated volute; 10, front cover plate; 100, air inlet; 20, rear cover plate; 200, air outlet; 30, volute ring wall; 300, perforation; 301, straight-through hole; 302, profiled groove; 31, volute tongue section; 32, outlet section; 33, ring wall section; 330, oil leakage hole; 331, lower ring wall area; 332, volute tongue ring wall area; 40, sound absorption assembly; 41, ring wall sound absorption box; 42, cover plate sound absorption box; 2, impeller; 3, range hood box.
[0044] The above main element symbol explanation, in combination with the accompanying drawings and specific embodiments, further details the present application. DETAILED DESCRIPTION
[0045] To make the above objectives, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application are described in detail below in combination with the accompanying drawings. In the following description, a lot of specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited by the specific embodiments disclosed below.
[0046] In the description of the present application, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.
[0047] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.
[0048] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0049] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on another element or there can be a mediating element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a mediating element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation.
[0050] Considering that the centrifugal fan in the current range hood mainly optimizes the way of the volute through the design of the volute shape and the volute line, although some noise reduction schemes will open several noise reduction holes on the volute, these noise reduction holes usually adopt a single hole diameter uniform arrangement, which leads to poor noise reduction effect. Therefore, the present application provides a variable-diameter perforated volute, a centrifugal fan and a range hood, which can achieve better noise reduction effect under the premise of considering the air volume performance.
[0051] Specifically, with reference to the drawingsFigures 1 to 3 As shown, one embodiment of this application provides a range hood, which may include a range hood housing 3 and a centrifugal fan disposed within the range hood housing 3. The centrifugal fan includes a variable-diameter perforated volute 1 installed in the range hood housing 3 and an impeller 2 rotatably disposed within the variable-diameter perforated volute 1, so as to generate negative pressure when the impeller 2 rotates relative to the variable-diameter perforated volute 1, thereby achieving the effect of absorbing cooking fumes. It is understood that the range hood housing mentioned in this application may include, but is not limited to, components such as a fan chamber, a smoke collection chamber, and / or an oil cup, in addition to the centrifugal fan; these will not be elaborated further in this application.
[0052] More specifically, such as Figures 2 to 16 As shown, the variable-diameter perforated volute 1 may include a front cover plate 10 with an air inlet 100, a rear cover plate 20 spaced apart from the front cover plate 10, a volute annular wall 30, and a sound-absorbing component 40. The volute annular wall 30 is disposed between the front cover plate 10 and the rear cover plate 20 to form an air outlet 200 communicating with the air inlet 100; and the volute annular wall 30 has a plurality of perforations 300 with gradually changing apertures. The sound-absorbing component 40 is disposed on the outside of the volute annular wall 30 and covers the perforations 300. It is understood that the rear cover plate 20 mentioned in this application may have an air inlet to make the centrifugal fan a double-suction fan, or it may not have an air inlet to make the centrifugal fan a single-suction fan, which will not be described in detail in this application.
[0053] It is worth noting that, compared to a perforated volute with a single aperture, the variable-diameter perforated volute 1 of this application provides perforations 300 with gradually changing apertures on the volute annular wall 30 to match the non-uniformly distributed airflow within the volute, which is beneficial for balancing airflow performance and noise reduction. For example, the aperture of the perforation 300 can gradually change along the circumference of the volute annular wall 30.
[0054] Exemplarily, in the first example of this application, such as Figures 3 to 6 As shown, the volute annular wall 30 may include a volute tongue section 31, an outlet section 32 spaced apart from the volute tongue section 31 to form the air outlet 200, and an annular wall section 33 extending curvedly from the volute tongue section 31 to the outlet section 32. The diameter of the perforation 300 gradually increases along the circumference of the volute annular wall 30 from the volute tongue section 31 to the outlet section 32, such that the diameter of the perforation 300 near the volute tongue section 31 is smaller than the diameter of the perforation 300 away from the volute tongue section 31.
[0055] In this way, under the large flow design condition, the flow velocity of the air flow in the volute tongue section 31 of the volute ring wall 30 is large, the perforated hole arrangement with gradually increasing hole diameter is adopted for the volute ring wall 30, the part of the volute ring wall 30 close to the volute tongue section 31 with large flow velocity is opened with small hole diameter, that is, the hole diameter of the perforated hole 300 of the volute ring wall 30 close to the volute tongue section 31 is smaller, so that the leakage amount of the air flow with large flow velocity close to the volute tongue section 31 is reduced, so as to reduce the air volume and efficiency reduction caused by air flow leakage, and the air volume performance and noise reduction effect are considered.
[0056] Optionally, in the above-mentioned first example of the present application, the hole diameter of the perforated hole 300 is between 0 mm and 8 mm, and the circumferential hole diameter variation rate of the perforated hole 300 is between 0 and 20%. It can be understood that the hole diameter mentioned in the present application refers to the diameter of the perforated hole 300; the circumferential hole diameter variation rate mentioned in the present application refers to the ratio between the difference between the diameters of two circumferentially adjacent perforated holes 300 and the diameter of the current perforated hole 300. For example, as shown in Figure 5 the diameter of the current perforated hole 300 is d1, and the diameter of the next perforated hole 300 is d2, then the circumferential hole diameter variation rate ηy=(d2-d1) / d1×100%.
[0057] Preferably, in the above-mentioned first example of the present application, the circumferential hole diameter variation rate of the perforated hole 300 is 2.5%.
[0058] It is worth noting that in the above-mentioned first example of the present application, the hole spacing of the perforated hole 300 gradually increases along the circumference of the volute ring wall 30 from the volute tongue section 31 to the outlet section 32, so that the hole spacing between the perforated holes 300 with larger hole diameter is also larger, so as to ensure that the structural strength of each region of the volute ring wall 30 remains consistent, avoid weakening the structural strength of the corresponding region due to excessive partition opening rate, and improve the overall structural stability of the volute ring wall 30. Of course, in other examples of the present application, the hole spacing between any two adjacent perforated holes 300 can also remain equal, which will not be described herein. It can be understood that the hole spacing mentioned in the present application refers to the center distance between two adjacent perforated holes 300.
[0059] Optionally, the hole spacing between any two adjacent perforated holes 300 can be between 0 mm and 10 mm, and the circumferential hole spacing variation rate of the perforated hole 300 is between 0 and 10%. It can be understood that, as Figure 5As shown, the variation rate γ of the circumferential hole spacing mentioned in the present application refers to the ratio between the difference of the circumferential spacing s2 between the current perforation 300 and the next perforation 300 and the circumferential spacing s1 between the current perforation 300 and the previous perforation 300, i.e. γ = (s2-s1) / s1x100%.
[0060] In addition, for the centrifugal fan in the small flow design condition, since the airflow velocity in each area of the volute ring wall 30 is relatively small, the amount of air leakage is limited, and therefore in the second example of the present application, as shown in Figure 7 The hole diameter of the perforation 300 can gradually decrease along the circumference of the volute ring wall 30 from the volute tongue section 31 to the outlet section 32, so that the hole diameter of the perforation 300 near the volute tongue section 31 is larger than the hole diameter of the perforation 300 away from the volute tongue section 31. In this way, the perforation 300 with a larger hole diameter near the volute tongue section 31 can have a better noise reduction effect while considering the air volume performance.
[0061] Optionally, in the above-mentioned second example of the present application, the hole spacing of the perforation 300 can gradually decrease along the circumference of the volute ring wall 30 from the volute tongue section 31 to the outlet section 32, so as to ensure that the volute ring wall 30 has better overall structural stability.
[0062] According to the above-mentioned embodiments of the present application, as shown in Figure 2 and Figure 3 The lowest part of the ring wall section 33 of the volute ring wall 30 is provided with an oil leakage hole 330, so that the oil accumulated on the volute ring wall 30 flows to the lowest part of the ring wall section 33 under the action of its own gravity, and flows out from the oil leakage hole 330.
[0063] Optionally, as shown in Figure 2 and Figure 3 The oil leakage hole 330 is located on the side of the ring wall section 33 close to the rear cover plate 20, so that the oil leakage hole 330 can be aligned with the rear-arranged smoke collection cavity, so that the oil flows into the oil cup located at the bottom of the smoke collection cavity.
[0064] It is worth noting that for the range hood placed in front of and behind the centrifugal fan, due to the difference in air intake amount of the air inlet 100 on the front and rear sides of the variable-diameter perforated volute 1, the airflow distribution of the volute ring wall 30 in the axial direction is also uneven; therefore, the perforation 300 of the present application can also gradually change along the axial direction of the volute ring wall 30, so as to consider the air volume performance and noise reduction efficiency.
[0065] Exemplarily, in the third example of the present application, as shown in Figure 8 and Figure 9As shown, the hole diameter of the perforations 300 gradually decreases along the axial direction of the volute wall 30 from front to back, so that the hole diameter of the perforations 300 close to the back cover plate 20 is smaller than the hole diameter of the perforations 300 away from the back cover plate 20. In this way, since the air inlet 100 on the back cover plate 20 of the variable-diameter perforated volute 1 of the present application is the main air inlet, the flow rate of the air flow here is larger; therefore, the perforations of the volute wall 30 of the present application gradually decrease in hole diameter from front to back, so that the part of the volute wall 30 close to the main air inlet (i.e. the air inlet 100 on the back cover plate 20) uses small-diameter openings, so that the leakage amount of the air flow with a large flow rate at the back cover plate 20 is reduced, so as to reduce the air volume and efficiency decrease caused by air flow leakage, and to facilitate the consideration of air volume performance and noise reduction effect under large flow design conditions.
[0066] Optionally, the hole diameter of the perforations 300 is between 0 mm and 8 mm, and the axial hole diameter variation rate of the perforations 300 is between 0 and 30%. It can be understood that the axial hole diameter variation rate mentioned in the present application refers to the ratio between the difference in diameter of two adjacent perforations 300 in the axial direction and the diameter of the current perforation 300. For example, the diameter of the current perforation 300 is d1, and the diameter of the next perforation 300 is d2, then the axial hole diameter variation rate ηx = (d2-d1) / d1×100%.
[0067] Preferably, in the above-mentioned third example of the present application, the axial hole diameter variation rate of the perforations 300 is 15%.
[0068] Optionally, in the above-mentioned third example of the present application, the hole spacing of the perforations 300 gradually decreases along the axial direction of the volute wall 30 from front to back, so that the hole spacing between the perforations 300 with larger hole diameters is also larger, so as to ensure that the structural strength of each axial region of the volute wall 30 remains consistent, avoid weakening the structural strength of the corresponding region due to excessive partition opening rate, and improve the overall structural stability of the volute wall 30. For example, the hole spacing between any two adjacent perforations 300 can be between 0 mm and 10 mm, and the axial hole spacing variation rate of the perforations 300 is between 0 and 20%.
[0069] It is worth noting that, in the fourth example of the present application, as shown in Figure 10 and Figure 11 the hole diameter of the perforations 300 can gradually increase along the axial direction of the volute wall 30 from front to back, so that the hole diameter of the perforations 300 close to the back cover plate 20 is larger than the hole diameter of the perforations 300 away from the back cover plate 20. In this way, the perforations 300 with larger hole diameters close to the back cover plate 20 can balance the air volume performance under small flow design conditions while achieving better noise reduction effect.
[0070] Similarly, in the above fourth example of the present application, the hole spacing of the perforations 300 can gradually increase from front to back along the axial direction of the volute ring wall 30, so as to ensure that the volute ring wall 30 has better overall structural strength.
[0071] According to the above embodiments of the present application, as shown in Figure 6 The perforations 300 of the present application can be implemented as through holes 301 penetrating the volute ring wall 30 to communicate the inner and outer spaces of the volute ring wall 30, so that the internal space of the variable-diameter perforated volute 1 communicates with the sound-absorbing assembly 40, achieving a noise reduction effect.
[0072] Of course, in the first variant example of the present application, as shown in Figure 12 The perforations 300 can also be implemented as concave perforations, i.e. the perforations 300 can include a profiled groove 302 recessed outward from the inner wall of the volute ring wall 30 and a through hole 301 opened at the groove bottom of the profiled groove 302 and smaller in size than the slot size, which can break the near-wall boundary layer flow on the volute ring wall 30 to form turbulent flow, so that the airflow forms a vortex in the profiled groove 302 and dissipates to reduce the vibration and noise generated by airflow impact; at the same time, a part of the airflow is discharged through the through hole 301 to the sound-absorbing assembly 40, achieving a better noise reduction effect. It can be understood that in the first variant example of the present application, the perforations 300 can be made by outward profiling the part of the volute ring wall 30 where the through hole 301 is located.
[0073] It should be noted that in the above first variant example of the present application, the hole diameter of the perforations 300 can refer to the diameter of the through hole 301, at which time the slot diameter of the profiled groove 302 can remain unchanged; of course, the hole diameter of the perforations 300 can also refer to the slot diameter of the profiled groove 302, at which time the diameter of the through hole 301 can change correspondingly with the change of the slot diameter of the profiled groove 302.
[0074] Alternatively, as shown in Figure 12 The slot edge and groove bottom edge of the profiled groove 302 have a rounded corner structure, which not only reduces the airflow resistance at the slot, but also better guides the airflow into the profiled groove 302, and also reduces the airflow resistance in the groove, better guiding the airflow to form a vortex in the profiled groove 302.
[0075] It should be noted that in the above embodiments of the present application, the perforations 300 are arranged in an array on the volute ring wall 30, i.e. the perforations 300 are arranged linearly along the circumferential and axial directions of the volute ring wall 30, but this array arrangement results in that the perforations 300 can only cover a smaller actual sound absorption area at the same radiation radius.
[0076] Therefore, in the second variant example of the present application, as shown inFigure 13 As shown, the perforations 300 are arranged in a staggered pattern on the volute annular wall 30, allowing them to cover a larger actual sound-absorbing area within the same radiation radius. This achieves better noise reduction while maintaining the same perforation rate and airflow performance. It is understood that the staggered arrangement mentioned in this application refers to any two adjacent rows of perforations 300 being misaligned, such that no two adjacent perforations 300 are on the same horizontal line. Furthermore, this application defines the axial direction of the volute annular wall 30 as the horizontal direction (corresponding to the row of perforations 300) and the circumferential direction of the volute annular wall 30 as the vertical direction (corresponding to the column of perforations 300). Of course, in other embodiments of this application, the axial and circumferential directions of the volute annular wall 30 may also correspond to the column and row of perforations 300, respectively, which will not be elaborated further in this application.
[0077] Optionally, such as Figure 13 As shown, each row of perforations 300 on the volute annular wall 30 is distributed along a fish-scale-like zigzag pattern, ensuring a staggered arrangement of all perforations 300. It is understood that in other examples of this application, each row of perforations 300 on the volute annular wall 30 may be distributed along a wavy line or randomly, as long as a staggered arrangement of all perforations 300 is achieved. For example, each row of perforations 300 on the volute annular wall 30 may be distributed along a sine function curve, ensuring that any two adjacent perforations 300 are not on the same horizontal line.
[0078] According to the various examples described above in this application, the perforation 300 is formed in segmented regions spaced apart on the volute annular wall 30. For example, as Figures 2 to 13 As shown, the annular wall section 33 has a lower annular wall region 331 spaced apart from the outlet section 32 and adjacent to the oil leakage hole 330, and a volute tongue annular wall region 332 spaced apart from the lower annular wall region 331 and adjacent to the volute tongue section 31. The lower annular wall region 331 and the volute tongue annular wall region 332 are respectively provided with perforations 300 of gradually changing diameter, so as to segment the perforations according to the characteristics of the internal flow field distribution of the volute, thereby reducing the perforation ratio and processing cost. It is understood that since noise will not be significantly reduced when the perforation ratio reaches a certain level, and a smaller perforation ratio will reduce the decrease in airflow, static pressure, and efficiency caused by the perforations, this application can select an appropriate perforation ratio based on the trade-offs of airflow, static pressure, efficiency, and noise performance requirements of the range hood and fan design, while taking into account lower processing costs.
[0079] Optionally, such as Figure 2 and Figure 3As shown, the sound absorption assembly 40 includes a pair of ring wall sound absorption boxes 41 respectively covering the lower ring wall region 331 and the volute tongue ring wall region 332, so as to form sound absorption cavities communicating with the perforations 300 outside the volute ring wall 30, without covering all regions of the volute ring wall 30, which is conducive to reducing the configuration of sound absorption boxes and lowering the cost. It can be understood that the sound absorption boxes mentioned in the present application can be made of sound absorption cotton or can be implemented as a box filled with sound absorption cotton, which will not be described here.
[0080] It is worth noting that in the above embodiments of the present application, as shown in Figure 2 and Figure 3 , the sound absorption assembly 40 can further include a pair of cover plate sound absorption boxes 42 covering the outside of the front cover plate 10 and the rear cover plate 20 to absorb the noise generated at the front cover plate 10 and the rear cover plate 20, further improving the noise reduction effect.
[0081] In addition, in other embodiments of the present application, the perforations 300 can be formed on all regions of the volute ring wall 30 except the volute tongue segment 31 to form a full-ring wall perforation, as long as the perforations 300 are distributed with gradually changing diameters.
[0082] Exemplarily, in the third variant example of the present application, as shown in Figure 14 , the perforations 300 are formed on both the outlet segment 32 and the ring wall segment 33, and the diameters of the perforations 300 gradually increase along the circumference of the volute ring wall 30 from the volute tongue segment 31 to the outlet segment 32.
[0083] It is worth noting that in other variant examples of the present application, the diameters and / or the hole spacing of the perforations 300 on the volute ring wall 30 of the present application can also be designed to be locally gradually changed according to the flow field simulation results under the design working condition, in combination with the velocity and pressure distribution of the volute ring wall 30, without being gradually changed in a single direction along the circumference or the axis.
[0084] Exemplarily, since in the perforated volute of the centrifugal fan, in addition to the relatively large airflow velocity at the volute tongue segment 31 of the volute ring wall 30, the airflow velocity at the outlet segment 32 of the volute ring wall 30 is also relatively large; therefore, in the fourth variant example of the present application, as shown in Figure 15 , the diameters of the perforations 300 gradually increase first and then gradually decrease along the circumference of the volute ring wall 30 from the volute tongue segment 31 to the outlet segment 32, so that the diameters of the perforations 300 near the volute tongue segment 31 or the outlet segment 32 are relatively small, and the diameters of the perforations 300 away from the volute tongue segment 31 and the outlet segment 32 are relatively large, thereby reducing the leakage amount of the relatively large velocity airflow near the volute tongue segment 31 or the outlet segment 32, so as to further reduce the air volume and efficiency reduction caused by airflow leakage, which is conducive to balancing the air volume performance and noise reduction effect under the large flow design working condition.
[0085] Of course, in the fifth variant example of the present application, as shown in Figure 16 the hole diameter of the perforations 300 gradually decreases and then gradually increases along the circumferential direction of the volute ring wall 30 from the volute tongue section 31 to the outlet section 32, so that the hole diameter of the perforations 300 close to the volute tongue section 31 or the outlet section 32 is large, and the hole diameter of the perforations 300 away from the volute tongue section 31 and the outlet section 32 is small, and then the perforations 300 with large hole diameter adjacent to the volute tongue section 31 or the outlet section 32 can have a better noise reduction effect, so as to balance the air volume performance and noise reduction effect under the small flow design working condition.
[0086] The technical features of the above embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present disclosure.
[0087] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patentable scope of the application. It should be pointed out that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application.
Claims
1. A variable diameter perforated volute, characterized by, The application relates to a centrifugal fan, comprising: a front cover plate with an air inlet; a rear cover plate arranged in a spaced manner with the front cover plate; a volute ring wall, wherein the volute ring wall is arranged between the front cover plate and the rear cover plate to form an air outlet communicating with the air inlet, and a plurality of perforations with gradually changed hole diameters are formed in the volute ring wall; and a sound absorption assembly arranged outside the volute ring wall and covering the perforations.
2. The variable diameter perforated volute of claim 1, wherein, The hole diameters of the perforations gradually change along the circumferential direction and / or the axial direction of the volute ring wall.
3. The variable diameter perforated volute of claim 1, wherein, The volute ring wall comprises a volute tongue section, an outlet section arranged in a spaced manner with the volute tongue section to form the air outlet, and a ring wall section extending from the volute tongue section to the outlet section in a curved manner; the hole diameters of the perforations gradually increase or gradually decrease along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section.
4. The variable diameter perforated scroll of claim 3, wherein, The hole diameters of the perforations are between 0 mm and 8 mm, and the circumferential hole diameter change rate of the perforations is between 0 and 20%.
5. The variable diameter perforated volute of claim 3, wherein, The hole spacing of the perforations gradually increases or gradually decreases along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section; the hole spacing of the perforations is between 0 mm and 10 mm, and the circumferential hole spacing change rate of the perforations is between 0 and 10%.
6. The variable diameter perforated volute of claim 1, wherein, The volute ring wall comprises a volute tongue section, an outlet section arranged in a spaced manner with the volute tongue section to form the air outlet, and a ring wall section extending from the volute tongue section to the outlet section in a curved manner; the hole diameters of the perforations gradually increase first and then gradually decrease or gradually decrease first and then gradually increase along the circumferential direction of the volute ring wall from the volute tongue section to the outlet section.
7. The variable diameter perforated volute of claim 1, wherein, The hole diameters of the perforations gradually decrease or gradually increase along the axial direction of the volute ring wall from front to back; the space of the perforations is between 0 mm and 8 mm, and the axial hole diameter change rate of the perforations is between 0 and 30%; the axial hole spacing of the perforations gradually decreases or gradually increases along the axial direction of the volute ring wall from front to back; the axial hole spacing of the perforations is between 0 mm and 10 mm, and the axial hole spacing change rate of the perforations is between 0 and 20%.
8. The variable diameter perforated volute of any one of claims 1 to 7, wherein, The perforations are pit-type perforations or straight-through holes penetrating through the volute ring wall; the perforations are arranged in an array or a staggered array on the volute ring wall; the perforations are formed in segmented regions arranged in a spaced manner on the volute ring wall.
9. A centrifugal fan, characterized by The application relates to a centrifugal fan, comprising: a variable-diameter perforated volute according to any one of claims 1 to 8; and an impeller rotatably arranged in the variable-diameter perforated volute.
10. A range hood characterized by The application relates to a centrifugal fan, comprising: a range hood box; and a centrifugal fan according to claim 9 arranged in the range hood box.