Centrifugal wind wheel, centrifugal fan and device with centrifugal fan

Abstract

The invention relates to the technical field of electrical products, and discloses a centrifugal wind wheel, a centrifugal fan and a device with the centrifugal fan, the centrifugal wind wheel comprises a plurality of fan blades arranged in the circumferential direction, and the thicknesses of the fan blades are gradually increased and then gradually reduced in the direction away from the center of the centrifugal wind wheel. And an overflowing gap between every two adjacent fan blades is gradually increased and then gradually reduced. The direction far away from the center of the centrifugal wind wheel is actually the wind outlet direction, the overflowing gaps between every two adjacent fan blades are gradually increased and then gradually decreased in the wind outlet direction, the overflowing gaps are increased so that wind can smoothly enter the overflowing gaps, the overflowing gaps are decreased so that the airflow speed can be increased, and therefore airflow can be accelerated when flowing through the overflowing gaps; vortex at the inlet of the fan blade can be eliminated, efficiency can be improved, and noise can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical products, and in particular to a centrifugal wind wheel, a centrifugal fan and a device having the centrifugal fan. Background Art

[0002] The centrifugal fan includes a volute and an impeller disposed in the volute, and the impeller includes multiple blades. The traditional blades are generally arc-shaped. According to research, the traditional blades have poor working capacity, which leads to low fan efficiency and high noise. Since centrifugal fans are often used in living environments such as air conditioning coils and range hoods, the aerodynamic noise generated by their operation will affect the user experience. Summary of the invention

[0003] In view of this, the present invention provides a centrifugal wind wheel, a centrifugal fan and a device having a centrifugal fan to solve the problems of low fan efficiency and high noise.

[0004] In a first aspect, the present invention provides a centrifugal wind wheel, comprising a plurality of wind blades arranged along a circumferential direction, wherein the thickness of the wind blades first gradually increases and then gradually decreases in a direction away from the center of the centrifugal wind wheel, and the flow gap between two adjacent wind blades first gradually increases and then gradually decreases.

[0005] Beneficial effect: The direction away from the center of the centrifugal wind wheel is actually the wind outlet direction. Since the flow gap between two adjacent fan blades gradually increases and then decreases along the wind outlet direction, the increase in the flow gap will allow the wind to enter the flow gap smoothly, and the decrease in the flow gap will cause the airflow velocity to accelerate. Therefore, the airflow passing through the flow gap will first accelerate, which can eliminate the vortex at the entrance of the fan blade, which is beneficial to improve efficiency and reduce noise.

[0006] In an optional embodiment, the fan blade has a leading edge and a trailing edge, and in a cross section perpendicular to the axial direction of the centrifugal fan wheel, the leading edge and / or the trailing edge includes a plurality of smoothly connected arc segments.

[0007] Beneficial effect: Since the leading edge and / or trailing edge of the fan blade includes a plurality of smoothly connected arc segments, the working capacity of the fan blade can be improved and the efficiency can be improved.

[0008] In an optional embodiment, there are a first tangent circle and a second tangent circle between two adjacent wind blades, the first tangent circle and the second tangent circle are tangent to the two wind blades at the same time, and the first tangent circle is tangent to the point of maximum thickness on the trailing edge of one of the wind blades, and the second tangent circle is tangent to the end of the leading edge of the other wind blade away from the center of the centrifugal wind wheel, the diameter of the first tangent circle is δmax, and the diameter of the second tangent circle is δmin, 1<δmax / δmin≤2.

[0009] In an optional embodiment, the inscribed circle of the wind blade at the maximum thickness is the third tangential circle, the inscribed circle of the wind blade at the end of its trailing edge away from the center of the centrifugal wind wheel is the fourth tangential circle, the diameter of the third tangential circle is Φmax, the diameter of the fourth tangential circle is Φmin, and 1<Φmax / Φmin≤2.

[0010] In an optional embodiment, the thickness of the fan blade is Φ, 1.6mm≤Φ≤3mm;

[0011] And / or, the flow gap is δ, 4mm≤δ≤7mm.

[0012] Beneficial effect: By experimentally comparing the centrifugal wind wheel that meets this range with the traditional centrifugal wind wheel, the air volume and outlet wind speed are effectively improved, which can delay the airflow separation, reduce the tail vortex shedding, and effectively reduce the sound pressure noise.

[0013] In an optional embodiment, the radius of the circle where the center line of the fan blade is located is R, 9.5mm≤R≤10mm;

[0014] And / or, the distribution angle of the wind blades is θ, 8°≤θ≤9°;

[0015] And / or, the line where the end of the fan blade away from the center of the centrifugal wind wheel is located is the first line, the circle where the center line of the fan blade is located is the first circle, and the angle between the tangent of the first circle at the intersection with the first line and the first line is β, 75°≤β≤80°.

[0016] Beneficial effect: The angle between the tangent of the first circle at the intersection with the first line and the first line specifically refers to the outlet angle. The outlet angle affects the separation of the airflow at the rear of the wind blade. By making the outlet angle between 75° and 80°, the airflow separation can be reduced and the aerodynamic efficiency can be improved.

[0017] In a second aspect, the present invention further provides a centrifugal fan including a volute and the centrifugal wind wheel.

[0018] Beneficial effect: Since the leading edge and / or trailing edge of the fan blade includes a plurality of smoothly connected arc segments, the working capacity of the fan blade can be improved and the efficiency can be improved.

[0019] In an optional embodiment, the volute includes a volute tongue and a volute throat, the outer surface of the volute includes an Archimedean spiral surface, the starting end of the Archimedean spiral surface is connected to the volute tongue, and the end of the Archimedean spiral surface is connected to the volute throat, and the radial dimension of the outer wall of the volute gradually increases from the starting end to the end.

[0020] Beneficial effect: The outer surface of the volute includes an Archimedean spiral surface, which can better reduce the air output of the centrifugal fan and improve work efficiency.

[0021] In an optional embodiment, on a cross section perpendicular to the axial direction of the centrifugal wind wheel, the profile of the volute includes an Archimedean spiral, the starting angle of the Archimedean spiral is α, the outlet angle of the Archimedean spiral is Y, the spiral opening of the Archimedean spiral is x, 50°<α<90°, 0<Y<90°, 15mm / rad<x<45mm / rad.

[0022] Beneficial effects: The spiral opening is small, which reduces the divergence distance of the air duct spiral line, can improve the air collection capacity, increase the wind pressure, and reduce the flow loss in the volute.

[0023] In an optional embodiment, along the radial direction, the gap between the volute at the starting end and the centrifugal wind wheel is the smallest, and the gap between the volute at the starting end and the centrifugal wind wheel is d, 5mm<d<10mm;

[0024] And / or, the angle between the tangent line of the Archimedean spiral surface at the starting end and the extension line of the snail throat is the snail tongue angle, and the snail tongue angle is ε, 0°<ε<90°.

[0025] Beneficial effect: The inclined volute tongue design can effectively reduce the turbulence between the centrifugal impeller and the volute tongue, suppress rotation noise, and improve the operating efficiency and reliability of the fan.

[0026] In an optional embodiment, air enters from both sides of the centrifugal wind wheel, the air inlet length of the first side of the centrifugal wind wheel is L1, the air inlet length of the second side of the centrifugal wind wheel is L2, a motor bracket is provided in the volute, the first side of the centrifugal wind wheel is close to the motor bracket, and L1<L2.

[0027] Beneficial effect: Since the air enters from both sides of the centrifugal wind wheel, the air volume can be increased. Since the first side of the centrifugal wind wheel is close to the motor bracket, the air inlet area of ​​the first side is small, so that the air inlet length of the first side of the centrifugal wind wheel is smaller than the air inlet length of the second side of the centrifugal wind wheel, and the overall air inlet volume can be increased.

[0028] In an optional embodiment, the volute includes a left volute and a right volute, the centrifugal wind wheel is installed on the fan shaft of the left volute, and the left volute is connected to the right volute.

[0029] Beneficial effect: By making the volute include a left volute and a right volute, it is convenient to install the centrifugal wind wheel inside the volute.

[0030] In an optional implementation, in the axial direction, the gap between the centrifugal wind wheel and the left volute is a, and the gap between the centrifugal wind wheel and the right volute is b, and a≤b.

[0031] Beneficial effect: By setting an assembly gap between the centrifugal wind wheel and the left volute and the right volute, assembly is facilitated and assembly failure due to size error is avoided.

[0032] In a third aspect, the present invention further provides a device having a centrifugal fan, comprising:

[0033] The centrifugal fan.

[0034] Beneficial effect: The device with a centrifugal fan can improve the working capacity of the centrifugal fan blades and improve efficiency. It can also increase the air volume and air outlet speed, and can effectively reduce sound pressure and noise.

[0035] In an optional embodiment, the device having a centrifugal fan is a bladeless fan.

[0036] Beneficial effects: The bladeless fan can improve the working capacity of the centrifugal fan blades and improve efficiency. It can also increase the air volume and air outlet speed, and effectively reduce sound pressure and noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 This is a schematic structural diagram of a centrifugal wind wheel according to an embodiment of the present invention;

[0039] Figure 2 for Figure 1 A front view of a centrifugal wind wheel is shown;

[0040] Figure 3 A schematic diagram for comparing the fan blades according to the embodiment of the present invention and the conventional fan blades;

[0041] Figure 4 for Figure 3 The enlarged view of point A in the middle;

[0042] Figure 5 This is a schematic diagram of a centrifugal wind wheel according to an embodiment of the present invention showing only two adjacent wind blades;

[0043] Figure 6 for Figure 5 The enlarged view of point B in the middle;

[0044] Figure 7 This is a schematic structural diagram of a centrifugal fan according to an embodiment of the present invention;

[0045] Figure 8 for Figure 7 The schematic diagram of the structure when the left volute and the right volute are assembled together;

[0046] Fig. 9 for Figure 7 An exploded view of a centrifugal fan is shown;

[0047] Fig.10 A schematic diagram showing the air inlet and outlet directions of a centrifugal fan;

[0048] Fig.11 is a side view of a centrifugal wind wheel;

[0049] Fig.12 for Figure 7 A cross-sectional view of a centrifugal fan is shown;

[0050] Fig.13 It is a schematic diagram of the volute profile of a centrifugal fan;

[0051] Fig.14 is a schematic diagram of a device with a centrifugal fan according to an embodiment of the present invention;

[0052] Fig.15 for Fig.14 A front view of a device having a centrifugal fan is shown;

[0053] Fig.16 It is a simulation diagram for simulating a traditional centrifugal fan and the centrifugal fan of this embodiment;

[0054] Fig.17 A comparison diagram of the relationship between pressure and air volume of the conventional volute and the volute of this embodiment;

[0055] Fig.18 A simulation diagram for simulating a traditional wind blade;

[0056] Fig.19 This is a simulation diagram of the bionic wind blade of this embodiment.

[0057] Description of reference numerals:

[0058] 1. Left volute; 101. Motor bracket; 2. Right volute; 3. Centrifugal fan wheel; 301. Fan blade; 3011. Leading edge; 3012. Trailing edge; 302. First line; 303. First circle; 4. Volute tongue; 5. Volute throat; 6. Head air duct; 1a. Traditional fan blade. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0060] The centrifugal fan includes a volute and an impeller disposed in the volute, and the impeller includes a plurality of blades. The traditional blades are generally arc-shaped. According to research, the traditional blades have poor working capacity, which leads to low fan efficiency. In the related technology, the air outlet area is usually increased to increase the air volume and air efficiency, but increasing the air outlet area will cause the size of the volute to increase. Therefore, how to improve the air outlet efficiency of the centrifugal fan without increasing the size of the volute has always been a technical direction of research in this field. The centrifugal fan makes a lot of noise during operation. Since centrifugal fans are often used in living environments such as air-conditioning coils and range hoods, the aerodynamic noise generated by their operation will affect the user experience.

[0061] Combine the following Figures 1 to 19 , describing an embodiment of the present invention.

[0062] According to an embodiment of the present invention, in a first aspect, a centrifugal wind wheel 3 is provided, comprising a plurality of wind blades 301 arranged along the circumferential direction, wherein the thickness of the wind blades 301 first gradually increases and then gradually decreases in a direction away from the center of the centrifugal wind wheel 3, and the flow gap between two adjacent wind blades 301 first gradually increases and then gradually decreases.

[0063] In this embodiment, the direction away from the center of the centrifugal wind wheel 3 is actually the wind outlet direction. Since the flow gap between two adjacent fan blades 301 gradually increases and then gradually decreases along the wind outlet direction, the increase in the flow gap will allow the wind to smoothly enter the flow gap, and the decrease in the flow gap will cause the airflow velocity to accelerate. Therefore, the airflow passing through the flow gap will be accelerated, which can eliminate the vortex at the entrance of the fan blade 301, which is beneficial to improving efficiency and reducing noise.

[0064] It should be noted that the fan blade 301 has a leading edge 3011 and a trailing edge 3012 , and the thickness of the fan blade 301 refers to the distance between the leading edge 3011 and the trailing edge 3012 .

[0065] In one embodiment, the fan blade 301 has a leading edge 3011 and a trailing edge 3012 , and in a cross section perpendicular to the axial direction of the centrifugal fan wheel 3 , the leading edge 3011 and / or the trailing edge 3012 includes a plurality of smoothly connected arc segments.

[0066] In this embodiment, since the leading edge 3011 and / or the trailing edge 3012 of the fan blade 301 includes a plurality of smoothly connected arc segments, the working capacity of the fan blade 301 can be improved and the efficiency can be improved.

[0067] Specifically in one embodiment, the leading edge 3011 and the trailing edge 3012 of the fan blade 301 both include multiple arc segments, which can ensure that the working capacity of the fan blade 301 is improved and the efficiency is improved.

[0068] Specifically in one embodiment, the leading edge 3011 and the trailing edge 3012 of the fan blade 301 both include three circular arc segments.

[0069] It should be noted that this embodiment does not limit the number of arc segments, and the number can be three or more.

[0070] Specifically in one embodiment, along the direction away from the center of the centrifugal wind wheel 3, the thickness of the wind blade 301 gradually increases first and then gradually decreases. Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the fan blade 301 of this embodiment is designed in the shape of a round whale with uneven thickness, while the traditional fan blade is in an arc shape. The thickness of the traditional fan blade remains basically unchanged along the direction away from the center of the centrifugal wind wheel. That is, the fan blade 301 of this embodiment is designed in the shape of a round whale (referred to as the bionic fan blade 301), which can eliminate the vortex at the entrance of the fan blade 301, which is conducive to improving efficiency and reducing noise.

[0071] Traditional fan blade Bionic wind blade <![CDATA[Air volume m 3 / min]]> 240 250↑ Outlet wind speed m / s 4.8 5.1↑ Sound pressure noise dB 61 59.5↓

[0072] Table 1

[0073] According to Table 1, under the premise that the other dimensions and shapes of the centrifugal fan remain unchanged, the air volume, outlet wind speed and sound pressure noise of the centrifugal fan using traditional fan blades and the centrifugal fan using bionic fan blades are compared. It is found that the air volume and outlet wind speed are significantly increased, and the sound pressure noise is significantly reduced.

[0074] By comparing the conventional fan blade 1a with the bionic fan blade 301 of this embodiment, Fig.18 and Fig.19 In this embodiment, the distance between the leading edge 3011 and the trailing edge 3012 of the fan blade 301 is not equal along the air outlet direction, and the air volume and outlet wind speed are effectively improved, which can delay the airflow separation, reduce the tail vortex shedding, and effectively reduce the sound pressure noise.

[0075] Specific as Fig.18 As shown in the figure, the blue dot structure represents the airflow. It can be clearly seen that there is no airflow on some blades, that is, the airflow has separated from the blades, which will cause a high sound pressure noise. Fig.19 ,and Fig.18In comparison, each fan blade has airflow, so compared with traditional fan blades, it delays flow separation, reduces tail vortex shedding, and can effectively reduce sound pressure noise.

[0076] In one embodiment, Figure 6 As shown, there are a first tangent circle and a second tangent circle between two adjacent wind blades 301, the first tangent circle and the second tangent circle are tangent to the two wind blades 301 at the same time, and the first tangent circle is tangent to the trailing edge 3012 of one of the wind blades 301 at the point of maximum thickness, and the second tangent circle is tangent to the end of the leading edge 3011 of the other wind blade 301 away from the center of the centrifugal wind wheel 3, the diameter of the first tangent circle is δmax, the diameter of the second tangent circle is δmin, 1<δmax / δmin≤2.

[0077] Specifically in one embodiment, δmax is 7 mm and δmin is 4 mm.

[0078] In one embodiment, further reference is made to Figure 6 The inscribed circle of the fan blade 301 at the maximum thickness is the third tangential circle, and the inscribed circle of the fan blade 301 at the end of its trailing edge 3012 away from the center of the centrifugal wind wheel 3 is the fourth tangential circle. The diameter of the third tangential circle is Φmax, and the diameter of the fourth tangential circle is Φmin, 1<Φmax / Φmin≤2.

[0079] Specifically in one embodiment, Φmax is 3 mm and Φmin is 1.6 mm.

[0080] In one embodiment, the thickness of the fan blade 301 is Φ, 1.6 mm≤Φ≤3 mm.

[0081] And / or, the flow gap is δ, 4mm≤δ≤7mm.

[0082] In this embodiment, by experimentally comparing the centrifugal wind wheel 3 that meets this range with the traditional centrifugal wind wheel, the air volume and outlet wind speed are effectively improved, the airflow separation can be delayed, the tail vortex shedding can be reduced, and the sound pressure noise can be effectively reduced.

[0083] In one embodiment, the radius of the circle where the center line of the fan blade is located is R, and 9.5 mm≤R≤10 mm.

[0084] Specifically in one embodiment, the radius of the circle where the center line of the fan blade lies is 9.7 mm.

[0085] Specifically in one embodiment, the radius of the circle where the center line of the fan blade lies is 10 mm.

[0086] Specifically in one embodiment, the radius of the circle where the center line of the fan blade lies is 9.5 mm.

[0087] In one embodiment, the distribution angle of the wind blades is θ, 8°≤θ≤10°.

[0088] It should be noted that the plurality of wind blades are evenly distributed at intervals of a distribution angle θ in the circumferential direction.

[0089] Specifically in one embodiment, the distribution angle of the wind blades is 8°.

[0090] Specifically in one embodiment, the distribution angle of the wind blades is 9°.

[0091] Specifically in one embodiment, the distribution angle of the wind blades is 10°.

[0092] In one embodiment, the line where the end of the fan blade away from the center of the centrifugal wind wheel 3 is located is the first line 302, the circle where the center line of the fan blade is located is the first circle 303, and the angle between the tangent of the first circle 303 at the intersection with the first line 302 and the first line 302 is β, 75°≤β≤80°.

[0093] In this embodiment, the angle between the tangent of the first circle 303 at the intersection with the first line 302 and the first line 302 specifically refers to the outlet angle. The outlet angle affects the separation of the airflow at the rear of the wind blade 301. By setting the outlet angle between 75° and 80°, the airflow separation can be reduced and the aerodynamic efficiency can be improved.

[0094] According to an embodiment of the present invention, in a second aspect, a centrifugal fan is provided, comprising a volute and the centrifugal wind wheel 3 provided in the above embodiment.

[0095] In this embodiment, since the leading edge 3011 and / or the trailing edge 3012 of the fan blade 301 includes a plurality of smoothly connected arc segments, the working capacity of the fan blade 301 can be improved and the efficiency can be improved.

[0096] like Fig.18 and Fig.19 , the centrifugal wind wheel 3 was simulated and compared with the traditional centrifugal wind wheel, and it was found that the air volume and outlet wind speed of the centrifugal wind wheel 3 were effectively improved, which can delay the separation of airflow, reduce the shedding of the tail vortex, and effectively reduce the sound pressure noise. Fig.18 As shown in the figure, the blue dot structure represents the airflow. It can be clearly seen that there is no airflow on some blades, that is, the airflow has separated from the blades, which will cause a high sound pressure noise. Fig.19 ,and Fig.18 In comparison, each fan blade has airflow, so compared with traditional fan blades, it delays flow separation, reduces tail vortex shedding, and can effectively reduce sound pressure noise.

[0097] In one embodiment, the volute includes a volute tongue 4 and a volute throat 5, and the outer surface of the volute includes an Archimedean spiral surface, the starting end of the Archimedean spiral surface is connected to the volute tongue 4, and the end of the Archimedean spiral surface is connected to the volute throat 5, and the radial dimension of the outer wall of the volute gradually increases from the starting end to the end.

[0098] In this embodiment, the outer surface of the volute includes an Archimedean spiral surface, which can better reduce the air output of the centrifugal fan and improve work efficiency.

[0099] In one embodiment, on a cross section perpendicular to the axial direction of the centrifugal wind wheel 3, the profile of the volute includes an Archimedean spiral, the starting angle of the Archimedean spiral is α, the outlet angle of the Archimedean spiral is Y, the spiral opening of the Archimedean spiral is x, 50°<α<90°, 0<Y<90°, 15mm / rad<x<45mm / rad.

[0100] It should be noted that the exit angle of the Archimedean spiral refers to the angle between the tangent line at the end of the Archimedean spiral and the vertical plane.

[0101] Specifically in one embodiment, the starting angle of the Archimedean spiral is 77°, and the exit angle of the Archimedean spiral is 8°.

[0102] Specifically in one embodiment, in a plane, the Archimedean spiral can be represented by the equation r=R+xt, theta=r0+360t, wherein r refers to the radius of the Archimedean spiral, x refers to the increase in radius per degree, that is, the spiral opening, and theta refers to the angle between the line connecting a certain point of the Archimedean spiral and the origin of the coordinate system and the X-axis.

[0103] Specifically in one embodiment, R=82 mm, r0=70°, 0≤t≤1, 15 mm / rad<x<45 mm / rad.

[0104] In this embodiment, the spiral opening is small, which reduces the divergence distance of the air duct spiral line, can improve the air collection capacity, increase the wind pressure, and reduce the flow loss in the volute.

[0105] Specifically in one embodiment, x=35 mm / rad.

[0106] In one embodiment, along the radial direction, the gap between the volute at the starting end and the centrifugal wind wheel 3 is the smallest, and the gap between the volute at the starting end and the centrifugal wind wheel 3 is d, 5mm<d<10mm.

[0107] In this embodiment, the gap between the volute at the starting end and the centrifugal wind wheel 3 is small, which can reduce eddy currents and turbulence and improve the operating efficiency and reliability of the fan.

[0108] Specifically in one embodiment, d=6.5 mm.

[0109] In one embodiment, the angle between the tangent line of the Archimedean spiral surface at the starting end and the extension line of the snail throat 5 is the snail tongue angle, and the snail tongue angle is ε, 0°<ε<90°.

[0110] In this embodiment, the inclined volute tongue 4 is designed to effectively reduce the turbulence between the centrifugal wind wheel 3 and the volute tongue 4, suppress the rotation noise, and improve the operation efficiency and reliability of the fan.

[0111] Specifically in one embodiment, the tongue angle is 66°.

[0112] Combination Fig.16 , Fig.16 is the turbulent kinetic energy cloud map, Fig.16 The left figure in the middle is a centrifugal fan with a traditional volute + straight volute tongue, and the right figure is a centrifugal fan with a volute + inclined volute tongue in this embodiment. Simulation analysis is performed on the centrifugal fan with a traditional volute + straight volute tongue and the centrifugal fan with a volute + inclined volute tongue in this embodiment. The traditional centrifugal fan has a large turbulent kinetic energy at the volute tongue, which is as high as 2.2 J / kg. The maximum turbulent kinetic energy at the volute tongue of the centrifugal fan in this embodiment is reduced from 2.2 J / kg to 1.5 J / kg. Therefore, the simulation analysis can effectively prove that the inclined volute tongue design adopted in this application can effectively reduce the turbulence between the centrifugal wind wheel 3 and the volute tongue 4 and suppress the rotation noise.

[0113] It should be noted that high turbulent kinetic energy means that there are more irregular movements in the airflow, while low turbulent kinetic energy means that the airflow is relatively stable. High turbulent kinetic energy will produce more eddies and vibrations, thereby increasing noise and possibly causing fluctuations in wind speed and a reduction in wind volume.

[0114] In one embodiment, Fig.10 As shown, the centrifugal wind wheel 3 has air entering from both sides. Fig.11 As shown, the air inlet length of the first side of the centrifugal wind wheel 3 is L1, the air inlet length of the second side of the centrifugal wind wheel 3 is L2, a motor bracket 101 is provided in the volute, the first side of the centrifugal wind wheel 3 is close to the motor bracket 101, and L1<L2.

[0115] In this embodiment, the air volume can be increased because the air enters from both sides of the centrifugal wind wheel 3. Since the first side of the centrifugal wind wheel 3 is close to the motor bracket 101, the air inlet area of ​​the first side is small, so that the air inlet length of the first side of the centrifugal wind wheel 3 is smaller than the air inlet length of the second side of the centrifugal wind wheel 3, and the overall air inlet volume can be increased.

[0116] Specifically in one embodiment, L1 = 47.5 mm, L2 = 64 mm.

[0117] Specifically in one embodiment, the diameter of the centrifugal wind wheel 3 is D, where D=152 mm.

[0118] In one embodiment, the volute includes a left volute 1 and a right volute 2 , the centrifugal wind wheel 3 is installed on the fan shaft of the left volute 1 , and the left volute 1 is butt-jointed with the right volute 2 .

[0119] In this embodiment, the volute includes a left volute 1 and a right volute 2, so that the centrifugal wind wheel 3 is conveniently installed inside the volute.

[0120] Specifically in one embodiment, the left volute 1 is provided with a motor bracket 101 .

[0121] Specifically in one embodiment, the left volute 1 and the right volute 2 are fixedly connected by screws and / or buckles.

[0122] In one embodiment, Fig.12 As shown, in the axial direction, the gap between the centrifugal wind wheel 3 and the left volute 1 is a, and the gap between the centrifugal wind wheel 3 and the right volute 2 is b, and a≤b.

[0123] In this embodiment, an assembly gap is provided between the centrifugal wind wheel 3 and the left volute 1 and the right volute 2, so as to facilitate assembly and avoid assembly failure due to size error.

[0124] Specifically in one embodiment, a=b=5.5 mm.

[0125] Flow rate (100Pa) noise Torque Traditional snail shell 223 73 / 98 0.144 This embodiment of the volute 240↑ 73 / 91 0.146

[0126] Table 2

[0127] As shown in Table 2, by comparing the conventional volute and the volute of this embodiment, it can be seen that the flow rate is increased and the noise is reduced.

[0128] The centrifugal fan provided in this embodiment optimizes the profile of the volute, reduces the divergence distance of the spiral line of the air duct, improves the air collection capacity, improves the air flow, and reduces the flow loss in the volute. The volute tongue 4 of the centrifugal fan adopts an inclined design, which effectively reduces the turbulence between the centrifugal wind wheel 3 and the volute tongue 4 and suppresses the rotation noise. The centrifugal fan has two-way air intake, which increases the air intake area, thereby increasing the air volume and improving the efficiency of the centrifugal fan. The fan blade 301 adopts a round-headed whale shape and a multi-section arc design to improve the working capacity of the fan blade 301 and improve efficiency. The front and rear edges 3012 of the fan blade 301 are designed with non-uniform thickness to delay airflow separation, reduce the shedding of the tail vortex, and reduce noise.

[0129] According to an embodiment of the present invention, in a third aspect, a device having a centrifugal fan is provided, comprising: the centrifugal fan provided in the above embodiment.

[0130] In this embodiment, the device with a centrifugal fan can improve the working capacity of the centrifugal fan blades 301 and improve efficiency. It can also increase the air volume and air outlet speed, and can effectively reduce sound pressure noise.

[0131] In one embodiment, the device having the centrifugal fan is a bladeless fan.

[0132] The bladeless fan can improve the working capacity of the centrifugal fan blades 301 and improve efficiency. It can also increase the air volume and air outlet speed, and can effectively reduce sound pressure and noise.

[0133] Specifically in one embodiment, Fig.14 and Fig.15 As shown, the bladeless fan includes a head air duct 6 and an air supply device. The air supply device is used to send high-speed airflow into the head air duct 6, increase pressure and accelerate, and shoot it out from the outlet gap at high speed, converge and drive the fluid flow, and send out natural and stable wind.

[0134] Wherein, the air supply device includes the above-mentioned centrifugal fan.

[0135] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the present application.

Claims

1. A centrifugal wind wheel, characterized in that: It comprises a plurality of fan blades (301) arranged along the circumferential direction, wherein in a direction away from the center of the centrifugal fan wheel (3), the thickness of the fan blades (301) first gradually increases and then gradually decreases, and the flow gap between two adjacent fan blades (301) first gradually increases and then gradually decreases.

2. The centrifugal wind wheel according to claim 1, characterized in that: The fan blade (301) has a leading edge (3011) and a trailing edge (3012); in a cross section perpendicular to the axial direction of the centrifugal fan wheel (3), the leading edge (3011) and / or the trailing edge (3012) comprises a plurality of smoothly connected circular arc segments.

3. The centrifugal wind wheel according to claim 2, characterized in that: A first tangent circle and a second tangent circle are provided between two adjacent wind blades (301), the first tangent circle and the second tangent circle are tangent to the two wind blades (301) at the same time, and the first tangent circle is tangent to the rear edge (3012) of one of the wind blades (301) at a point of maximum thickness, and the second tangent circle is tangent to an end of the front edge (3011) of the other wind blade (301) away from the center of the centrifugal wind wheel (3), the diameter of the first tangent circle is δmax, the diameter of the second tangent circle is δmin, and 1<δmax / δmin≤2.

4. The centrifugal wind wheel according to claim 2, characterized in that: The inscribed circle of the fan blade (301) at the maximum thickness is a third tangential circle, the inscribed circle of the fan blade (301) at one end of its trailing edge (3012) away from the center of the centrifugal wind wheel (3) is a fourth tangential circle, the diameter of the third tangential circle is Φmax, the diameter of the fourth tangential circle is Φmin, and 1<Φmax / Φmin≤2.

5. The centrifugal wind wheel according to claim 1, characterized in that: The thickness of the fan blade (301) is Φ, 1.6 mm ≤ Φ ≤ 3 mm; And / or, the flow gap is δ, 4mm≤δ≤7mm.

6. The centrifugal wind wheel according to any one of claims 1 to 5, characterized in that: The radius of the circle where the center line of the fan blade is located is R, 9.5mm≤R≤10mm; And / or, the distribution angle of the wind blades is θ, 8°≤θ≤9°; And / or, the line on which one end of the fan blade away from the center of the centrifugal fan wheel (3) lies is a first line (302), the circle on which the center line of the fan blade lies is a first circle (303), and the angle between the tangent of the first circle (303) at the intersection with the first line (302) and the first line (302) is β, and 75°≤β≤80°.

7. A centrifugal fan, characterized in that: It comprises a volute and a centrifugal wind wheel (3) according to any one of claims 1 to 6.

8. The centrifugal fan according to claim 7, characterized in that: The volute comprises a volute tongue (4) and a volute throat (5); the outer surface of the volute comprises an Archimedean spiral surface; the starting end of the Archimedean spiral surface is connected to the volute tongue (4); the end of the Archimedean spiral surface is connected to the volute throat (5); and the radial dimension of the outer wall of the volute gradually increases from the starting end to the end.

9. The centrifugal fan according to claim 8, characterized in that: In a cross section perpendicular to the axial direction of the centrifugal wind wheel (3), the profile of the volute includes an Archimedean spiral, the starting angle of the Archimedean spiral is α, the outlet angle of the Archimedean spiral is Y, the spiral opening of the Archimedean spiral is x, 50°<α<90°, 0<Y<90°, 15mm / rad<x<45mm / rad.

10. The centrifugal fan according to claim 8, characterized in that: In the radial direction, the gap between the volute at the starting end and the centrifugal wind wheel (3) is the smallest, and the gap between the volute at the starting end and the centrifugal wind wheel (3) is d, 5mm<d<10mm; And / or, the angle between the tangent line of the Archimedean spiral surface at the starting end and the extension line of the snail throat (5) is the snail tongue (4) angle, and the snail tongue (4) angle is ε, 0°<ε<90°.

11. The centrifugal fan according to any one of claims 7 to 10, characterized in that: Air enters from both sides of the centrifugal wind wheel (3); the air inlet length of the first side of the centrifugal wind wheel (3) is L1; the air inlet length of the second side of the centrifugal wind wheel (3) is L2; ​​a motor bracket (101) is provided in the volute; the first side of the centrifugal wind wheel (3) is close to the motor bracket (101), and L1<L2.

12. The centrifugal fan according to claim 11, characterized in that: The volute comprises a left volute (1) and a right volute (2), the centrifugal wind wheel (3) is mounted on the fan shaft of the left volute (1), and the left volute (1) is butt-jointed with the right volute (2).

13. The centrifugal fan according to claim 12, characterized in that: In the axial direction, the gap between the centrifugal wind wheel (3) and the left volute (1) is a, and the gap between the centrifugal wind wheel (3) and the right volute (2) is b, and a≤b.

14. A device having a centrifugal fan, characterized in that: include: The centrifugal fan according to any one of claims 7 to 13.

15. The device with a centrifugal fan according to claim 14, characterized in that: The device with the centrifugal fan is a bladeless fan.

Images