Impeller, centrifugal fan, heating and ventilation indoor unit and heating and ventilation system

Abstract

The invention discloses an impeller, a centrifugal fan, a heating and ventilation indoor unit and a heating and ventilation system. The impeller comprises a wheel disc and a plurality of blades, and the blades are arranged on the wheel disc at intervals in the circumferential direction of the wheel disc; wherein each blade is provided with an inner side edge and an outer side edge which are opposite, the section, perpendicular to the axial direction of the wheel disc, of each blade is in a non-equal-thickness shape, the maximum thickness of each blade is D1, the minimum thickness of each blade is D2, the chord length of each blade is L, the distance between the maximum thickness position of each blade and the inner side edge is A, the distance between the minimum thickness position of each blade and the inner side edge is B, and the impeller meets the condition that D1 / L is larger than 0.1 and smaller than 0.3; d2 / D1 is more than 0.3 and less than 0.6; 0.2 < A / L < 0.35; b / L > = 0.9. According to the impeller, the non-equal-thickness blades are adopted, the maximum thickness position and the minimum thickness position of the blades and the proportion range of the thickness and the chord length of the blades are limited, the molded lines of the blades are optimized, and therefore vortexes and the high-low pressure difference are reduced, the fan efficiency is improved, and the noise problem is solved.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning systems, and in particular to an impeller, a centrifugal fan, a HVAC indoor unit and a HVAC system. Background Art

[0002] In the related art, centrifugal fans usually use arc-shaped blades of equal thickness, and the blade profile is relatively simple for easy processing and forming. However, when such blades rotate with the fan, vortices are easily formed and negative pressure is formed on the suction surface. The negative pressure causes the airflow to easily leave the suction surface, thereby reducing the wind pressure performance and generating large aerodynamic noise. Summary of the invention

[0003] The present application provides an impeller, a centrifugal fan, a HVAC indoor unit and a HVAC system, and is at least used to improve the noise problem of the impeller.

[0004] In the first aspect, the impeller provided by the present application includes a disk and a plurality of blades, wherein the plurality of blades are arranged on the disk at intervals along the circumference of the disk; wherein the blades have relative inner and outer edges, the blades are of non-uniform thickness along a cross section perpendicular to the axial direction of the disk, the maximum thickness of the blades is D1, the minimum thickness of the blades is D2, the chord length of the blades is L, the distance between the maximum thickness position of the blades and the inner edge is A, the distance between the minimum thickness position of the blades and the inner edge is B, and the impeller satisfies 0.1<D1 / L<0.3; 0.3<D2 / D1<0.6; 0.2<A / L<0.35; B / L≥0.9.

[0005] The impeller of the embodiment of the present application adopts a blade of non-uniform thickness. By limiting the maximum thickness position, minimum thickness position and the ratio range of the thickness to the chord length of the blade, the blade profile is optimized, thereby reducing eddy currents and high and low pressure differences, improving fan efficiency and improving noise problems.

[0006] In some embodiments, the blade is arranged with uniform thickness from the minimum thickness position of the blade to the outer edge.

[0007] In this way, by setting the blade to have the same thickness from the minimum thickness position to the outer edge, the blade is thinner at the outer edge and the end near the outer edge, which is beneficial to reducing the weight of components and improving efficiency while avoiding noise as much as possible.

[0008] In some embodiments, the blade includes a pressure surface and a suction surface facing each other, and the suction surface and the pressure surface transition into a circular arc at the inner edge.

[0009] In this way, the arc transition between the suction surface and the pressure surface at the inner edge is helpful to optimize the airflow guide path, thereby reducing noise.

[0010] In certain embodiments, the midline of the cross-section is an arcuate curve.

[0011] In this way, by setting the center line of the cross section to be an arched curve, the airflow is not easy to separate from the pressure surface, thereby reducing noise.

[0012] In certain embodiments, the maximum deflection between the center line of the cross section and the chord of the center line is f, satisfying: 0.15<f / L<0.25.

[0013] In this way, by setting the maximum deflection range of the center line of the cross section and the chord of the center line reasonably, the blade has a reasonable curvature shape, and the wind pressure distribution on the pressure surface and the suction surface is optimized, which is beneficial to reduce noise and improve air outlet efficiency.

[0014] In certain embodiments, the distance between the position of the maximum deflection of the midline of the cross section and the inner edge is C, satisfying 0.38<C / L<0.5.

[0015] In this way, by setting the ratio of the position of the maximum deflection of the midline of the cross-section and the distance from the inner edge to the chord length to be greater than 0.38 and less than 0.5, the deflection of the blade from the inner edge to the outer edge changes more rapidly, thereby optimizing the airflow path and wind pressure distribution, thereby reducing noise and improving air outlet efficiency.

[0016] In some embodiments, the inlet angle of the blade is β1, satisfying 51°≤β1≤61°

[0017] In this way, by setting the inlet angle β1 of the blade within a reasonable range, the airflow is ensured to smoothly enter and discharge the impeller, the resistance loss is reduced, the air volume is increased, the static pressure is increased, and the noise can be further reduced.

[0018] In certain embodiments, the outlet angle of the blade is β2, satisfying 136°≤β2≤146°.

[0019] In this way, by setting the outlet angle β2 of the blade within a reasonable range, the rotation speed and physical size of the impeller can be reduced, the weight can be reduced, and the noise can be reduced while the flow rate and total pressure are the same.

[0020] In some embodiments, the number of blades located on the same side of the wheel disk is Z, satisfying 41≤Z≤61.

[0021] In this way, the air outlet efficiency of the impeller is improved by setting the number of blades within a reasonable range.

[0022] In certain embodiments, the impeller further comprises an end ring, each of the plurality of blades extends from the wheel disk to the end ring, and along the extension trajectory of the blade, the cross-sectional shape of the blade perpendicular to the axial direction of the wheel disk remains unchanged.

[0023] In this way, as each blade extends from the wheel disc to the end ring, the cross-sectional shape of the blade perpendicular to the axial direction of the wheel disc remains unchanged, so that the end ring supports the blade and improves the structural strength.

[0024] In certain embodiments, the end ring protrudes from the blades in the radial direction of the impeller, and includes a base ring and a protrusion protruding outward from the base ring in the radial direction of the impeller, wherein the protrusion and the base ring together form a groove.

[0025] In this way, by providing the base ring and the protrusion protruding outward from the base ring along the radial direction of the impeller, the overall thickness of the end ring is increased, thereby further improving the structural strength of the end ring. The protrusion and the base ring form a groove together, and the thickness of the end ring is locally thinned, thereby avoiding the defect of shrinkage and deformation of the end ring to a certain extent.

[0026] In some embodiments, blades and end rings are provided on both sides of the wheel disc in the thickness direction.

[0027] In this way, by arranging blades and end rings on both sides of the wheel disc in the thickness direction, the air output is increased, the structural support is enhanced, and the structural stability is ensured.

[0028] In a second aspect, the present application provides a centrifugal fan, comprising a volute and an impeller according to any one of the above-mentioned embodiments, wherein the impeller is accommodated in the volute.

[0029] The centrifugal fan of the embodiment of the present application has all the beneficial effects of the impeller of the embodiment of the present application because it includes the impeller of any of the above-mentioned embodiments.

[0030] In some embodiments, the volute includes two side panels and a surrounding plate that are arranged opposite to each other, the surrounding plate extends circumferentially to form a volute profile line, the two side panels that are arranged opposite to each other are respectively connected to the two sides of the surrounding plate, and at least one side plate is provided with an air inlet; wherein at least one side panel is detachably connected to the surrounding plate, at least one side panel is made of a first material, and the surrounding plate is made of a second material, and the density of the first material is less than the density of the second material.

[0031] In this way, under the same volume, by making at least one side panel of the first material with a lower density, the volute can have the advantages of light weight and low cost, that is, the transportation cost, installation cost and manufacturing cost of the volute are lower when the weight is lower. In addition, since the enclosure is made of the second material with a higher density, the overall structural strength of the volute can still meet the requirements. By arranging the air inlet on the side panel, the airflow into the volute can be more effectively controlled and guided, so that the air flow inside the volute can be increased, thereby improving the heat dissipation efficiency.

[0032] In a third aspect, the present application provides a HVAC indoor unit, which includes a centrifugal fan according to any of the above-mentioned embodiments.

[0033] In this way, the airflow is accelerated by the centrifugal fan, which helps the circulation of air and improves the heat exchange effect.

[0034] In some embodiments, the HVAC indoor unit includes a first machine and a second machine, the first machine includes a first box and a centrifugal fan, the centrifugal fan is arranged in the first box, the second machine includes a second box and a heat exchanger, the heat exchanger is arranged in the second box, and the first box and the second box are detachably connected.

[0035] The centrifugal fan and the heat exchanger are matched in the first machine and the second machine which are detachably connected, so as to accelerate the circulation and heat exchange of air and improve the efficiency of the indoor HVAC unit.

[0036] In a fourth aspect, the present application provides a HVAC system, which includes a HVAC indoor unit and an air-conditioning outdoor unit according to any one of the above-mentioned embodiments, wherein the air-conditioning outdoor unit is connected to the HVAC indoor unit via a pipeline.

[0037] In this way, the centrifugal fan accelerates the air circulation in the HVAC indoor unit, thereby improving the heat exchange effect of the HVAC system between indoor and outdoor.

[0038] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0040] Figure 1 is a schematic diagram of the structure of an impeller in certain embodiments of the present application;

[0041] Figure 2 is a schematic diagram of the structure of an impeller in some embodiments of the present application from a left perspective;

[0042] Figure 3 is a schematic cross-sectional view of a blade according to certain embodiments of the present application;

[0043] Figure 4 is a comparison diagram of blades of certain embodiments of the present application and blades of equal thickness of a prior art example;

[0044] Figure 5 is a schematic diagram of the motion trajectory of a blade in certain embodiments of the present application;

[0045] Figure 6 This application Figure 5 An enlarged schematic diagram of a leaf;

[0046] Figure 7is a noise spectrum comparison diagram of the impeller of certain embodiments of the present application and the impeller of the prior art;

[0047] Figure 8 is a schematic diagram of the structure of an impeller in some embodiments of the present application from a front view perspective;

[0048] Fig. 9 is a schematic cross-sectional structure diagram of a centrifugal fan in certain embodiments of the present application;

[0049] Fig.10 yes Fig. 9 The enlarged structural diagram of the impeller in part E;

[0050] Fig.11 yes Fig. 9 The enlarged structural diagram of the impeller in part F;

[0051] Fig.12 is a schematic diagram of the cross-sectional structure of an end ring in certain embodiments of the present application;

[0052] Fig.13 is a schematic diagram of the cross-sectional structure of the end ring in other embodiments of the present application;

[0053] Fig.14 is a schematic cross-sectional structure diagram of an end ring according to another embodiment of the present application;

[0054] Fig.15 is a schematic structural diagram of a centrifugal fan in certain embodiments of the present application;

[0055] Fig.16 is a schematic diagram of the structure of a HVAC indoor unit in certain embodiments of the present application;

[0056] Fig.17 is a schematic structural diagram of a HVAC indoor unit in certain embodiments of the present application from another perspective;

[0057] Fig.18 It is a schematic diagram of the working principle of the HVAC system of certain embodiments of the present application.

[0058] Description of reference numerals:

[0059] 1000-centrifugal fan; 100-impeller; O-rotation center; 101-peripheral side; 10-wheel disc; 20-blade; 21-inner edge; 22-outer edge; 23-pressure surface; 24-suction surface; 25-blade channel; 201-center line; 20A-equal thickness blade; 30-end ring; 31-base ring; 311-annular surface; 312-first side surface; 32-protrusion; 321-second side surface; 322-connecting section; 323-extension section; 33-groove; 200-volute; 210-side plate; 211-air inlet; 220-enclosure; 221-volute tongue; 222-sinking groove;

[0060] 2000-HVAC system; 2100-HVAC indoor unit; 300-first machine; 310-first box; 400-second machine; 410-second box; 420-heat exchanger; 2200-air conditioner outdoor unit; 2300-pipeline; 500-compressor; 600-flow switching device; 700-outdoor heat exchanger; 800-expansion valve. DETAILED DESCRIPTION

[0061] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0062] In the description of the embodiments of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0063] In the description of the implementation methods of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the implementation methods of the present application can be understood according to specific circumstances.

[0064] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0065] The disclosure below provides many different embodiments or examples to realize different structures of the embodiments of the present application. In order to simplify the disclosure of the embodiments of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. The embodiments of the present application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the embodiments of the present application provide various specific processes and examples of materials, but those of ordinary skill in the art can appreciate the application of other processes and / or the use of other materials.

[0066] See also Figure 1-Figure 3 The impeller 100 provided in the present application includes a wheel disc 10 and a plurality of blades 20, wherein the plurality of blades 20 are arranged on the wheel disc 10 at intervals along the circumference of the wheel disc 10. The blades 20 have opposite inner edges 21 and outer edges 22, and the blades 20 are of non-uniform thickness along the cross section perpendicular to the axial direction of the wheel disc 10, the maximum thickness of the blade 20 is D1, the minimum thickness of the blade 20 is D2, the chord length of the blade 20 is L, the distance between the maximum thickness position of the blade 20 and the inner edge 21 is A, and the distance between the minimum thickness position of the blade 20 and the inner edge 21 is B, and the impeller 100 satisfies 0.1<D1 / L<0.3; 0.3<D2 / D1<0.6; 0.2<A / L<0.35; B / L≥0.9.

[0067] The impeller 100 of the embodiment of the present application adopts a blade 20 of non-uniform thickness. By limiting the maximum thickness position, the minimum thickness position and the ratio range of the thickness to the chord length of the blade 20, the profile of the blade 20 is optimized, thereby reducing vortices and high and low pressure differences, improving fan efficiency, and improving noise problems.

[0068] Specifically, the blades 20 are arranged at the edge of the wheel disc 10 and surround the wheel disc 10. When the blades 20 rotate with the wheel disc 10, an airflow is formed that enters the impeller 100 along the axial direction of the wheel disc 10, and an airflow is formed that leaves the impeller 100 along the radial direction of the wheel disc 10. Accordingly, the inner edges 21 of the plurality of blades 20 surround the air inlet, and the outer edges 22 are closer to the air outlet of the impeller 100 than the inner edges 21. Obviously, the impeller 100 rotates around the central axis of the wheel disc 10, the axial direction of the impeller 100 is parallel to the thickness direction of the wheel disc 10, the circumferential direction of the impeller 100 is parallel to or coincides with the circumferential direction of the wheel disc 10, and the radial direction of the impeller 100 is parallel to or coincides with the radial direction of the wheel disc 10.

[0069] It should be noted that the chord length L of the blade 20 refers to the straight-line distance between the inner edge 21 and the outer edge 22. The thickness direction of the blade 20 is perpendicular to the chord length direction, that is, the relative direction of the inner edge 21 and the outer edge 22. The thickness of the blade 20 (including the maximum thickness D1 and the minimum thickness D2 of the blade 20) is the dimension obtained on the cross section of the blade 20 along the direction perpendicular to the chord length, wherein the cross section of the blade 20 is perpendicular to the axial direction of the impeller 100 and parallel to the radial direction of the impeller 100. The distance A between the maximum thickness position of the blade 20 and the inner edge 21 and the distance B between the minimum thickness position of the blade 20 and the inner edge 21 are both distances along the chord length direction.

[0070] The flow channel formed between two adjacent blades 20 arranged along the circumference of the impeller 10 is the blade channel 25. When the impeller 100 rotates, vortices and pressure differences are easily generated in the blade channel 25. The maximum thickness D1, the minimum thickness D2 and the chord length L of the blade 20 satisfy 0.1<D1 / L<0.3, 0.3<D2 / D1<0.6, which limits the ratio of the width of the blade channel 25 along the circumference of the impeller 100 to the chord length L. The distance A between the maximum thickness position of the blade 20 and the inner edge 21 and the distance B between the minimum thickness position and the inner edge 21 satisfy 0.2<A / L<0.35, B / L≥0.9, that is, the maximum thickness position of the blade 20 is close to the inner edge 21 in the chord length direction, and the minimum thickness position of the blade 20 is close to the outer edge 22 in the chord length direction, which limits the width change trend of the blade channel 25. By designing the thickness of the blade 20 to vary in a specific trend, the aerodynamic performance of the blade 20 is improved, and the vortex and pressure difference in the blade passage 25 are reduced.

[0071] See also Figure 4 , Figure 4The dashed line portion indicates an equal-thickness blade 20A, and the solid line portion indicates the impeller 100 of the embodiment of the present application. The chord length L, maximum thickness D1, minimum thickness D2, maximum thickness position and minimum thickness position of the blade 20 of the embodiment of the present application meet the conditions of 0.1<D1 / L<0.3, 0.3<D2 / D1<0.6, 0.2<A / L<0.35, B / L≥0.9. When the chord length L is the same, the thickness of the blade 20 is thinner as a whole compared to the equal-thickness blade 20A, the maximum thickness D1 of the blade 20 is still less than the thickness of the equal-thickness blade 20A, and the end of the blade 20 close to the inner edge 21 is thicker, and the end close to the outer edge 22 is thinner. The overall thinning of the blade 20 is also conducive to reducing the weight of the blade 20 and improving the efficiency of the centrifugal fan 1000.

[0072] In a preferred embodiment, the maximum thickness D1, the minimum thickness D2, the chord length L, the distance A between the maximum thickness position and the inner edge 21, and the distance B between the minimum thickness position and the inner edge 21 of the blade 20 satisfy: D1 / L=0.15, D2 / D1=0.428, A / L=0.27, B / L=0.9.

[0073] See also Figure 3 In some embodiments, the blade 20 is arranged with a constant thickness from the minimum thickness position of the blade 20 to the outer edge 22 .

[0074] In this way, by setting the blade 20 to have the same thickness from the minimum thickness position to the outer edge 22, the blade 20 is thinner at the outer edge 22 and the end near the outer edge 22, which is beneficial to reducing the weight of components and improving efficiency while avoiding noise as much as possible.

[0075] Specifically, the ratio of the distance B from the minimum thickness position of the blade 20 to the inner edge 21 to the chord length L is greater than or equal to 0.9, and the thickness of the blade 20 is equal from the minimum thickness position of the blade 20 to the outer edge 22. Exemplarily, taking B / L=0.9 as an example, the one-ninth portion of the blade 20 close to the outer edge 22 along the chord length direction has the minimum thickness D2.

[0076] Optionally, combined Figure 2 The outer edge 22 of the blade 20 is connected to the end ring 30 to improve the structural strength. The outer edge 22 and the end ring 30 can form the outer peripheral side 101 of the blade 20. The end of the blade 20 close to the outer peripheral side 101 is thinner, which is beneficial for the impeller 100 to accelerate and guide the airflow and improve the air outlet efficiency.

[0077] See also Figure 2 and Figure 3 In some embodiments, the blade 20 includes a pressure surface 23 and a suction surface 24 that are opposite to each other, and the suction surface 24 and the pressure surface 23 transition in a circular arc at the inner edge 21 .

[0078] In this way, the arc transition between the suction surface 24 and the pressure surface 23 at the inner edge 21 is helpful to optimize the airflow guide path, thereby reducing noise.

[0079] Specifically, the pressure surface 23 and the suction surface 24 are two side surfaces of the blade 20 along the thickness direction of the blade 20, and the blade 20 protrudes from the pressure surface 23 to the suction surface 24. When the blade 20 rotates with the impeller 100, the pressure surface 23 faces the direction of rotation (the r direction as shown in the figure), so that the suction surface 24 faces the wind and forms a negative pressure, and the pressure surface 23 faces the wind and forms a positive pressure. In the related art, the airflow on the suction surface 24 is easy to separate from the suction surface 24, and the separation of the airflow will reduce the wind pressure performance and bring noise. The blade 20 of the embodiment of the present application is designed with a specific thickness change, and the pressure surface 23 and the suction surface 24 transition with an arc surface at the inner edge 21, so as to reduce the pressure difference between the pressure surface 23 and the suction surface 24 as much as possible, and to separate the wall airflow from the suction surface 24 as much as possible, thereby reducing noise.

[0080] Optionally, the center O1 of the arc transition surface between the suction surface 24 and the pressure surface 23 at the inner edge 21 falls on the center line 201 of the cross section.

[0081] See also Figure 2 and Figure 3 In some embodiments, the midline 201 of the cross section is an arched curve.

[0082] In this way, by setting the center line 201 of the cross section to be an arched curve, the airflow is not easy to separate from the pressure surface 23, thereby reducing noise.

[0083] Specifically, the cross section of the blade 20 in the embodiment of the present application refers to a cross section perpendicular to the axial direction of the impeller 100. The blade 20 is as follows: Figure 8 The cross section shown is a solid body formed by stacking along the axial direction of the impeller 100. The chord length L of the blade 20 is the chord length L of the center line 201 of the cross section, that is, the chord length L of the blade 20 is the line connecting the two intersection points of the center line 201 of the cross section through the inner edge 21 and the outer edge 22. The center line 201 of the cross section forms a curve that arches from the pressure surface 23 to the suction surface 24.

[0084] Optionally, the chord length direction of the blade 20 forms an angle with the radial direction of the impeller 100 , and the angle between the chord length direction and the radial direction of the impeller 100 is an acute angle.

[0085] See also Figure 3 In some embodiments, the maximum deflection of the center line 201 of the cross section and the chord of the center line 201 is f, satisfying: 0.15<f / L<0.25.

[0086] In this way, by setting the maximum deflection f range of the center line 201 of the cross section and the chord of the center line 201 to be reasonable, the blade 20 has a reasonable curvature shape, and the wind pressure distribution on the pressure surface 23 and the suction surface is optimized, which is beneficial to reduce noise and improve air outlet efficiency.

[0087] Specifically, the value of the deflection is consistent with the vertical distance between the center line 201 of the cross section and the chord of the center line 201. The ratio of the maximum vertical distance between the center line 201 of the cross section of the blade 20 of the embodiment of the present application and the chord length L is greater than 0.15 and less than 0.25. In a preferred embodiment, f / L=0.219.

[0088] See also Figure 3 In some embodiments, the distance between the position of the maximum deflection of the center line 201 of the cross section and the inner edge 21 is C, satisfying 0.38<C / L<0.5.

[0089] Combination Figure 4 The maximum deflection f of the blade 20 in the embodiment of the present application is greater than the maximum deflection of the blade 20A with equal thickness, and the deflection of the blade 20 is larger overall, and the position of the maximum deflection of the center line 201 of the cross section is closer to the inner edge 21 than the distance between the blade 20A with equal thickness. That is, the bending of the blade 20 from the inner edge 21 to the outer edge 22 in the embodiment of the present application is faster and more obvious.

[0090] In this way, by setting the ratio range of the distance C between the position of the maximum deflection of the center line 201 of the cross section and the inner edge 21 to be greater than 0.38 and less than 0.5, the deflection of the blade 20 from the inner edge 21 to the outer edge 22 changes more quickly, thereby optimizing the airflow path and wind pressure distribution, thereby reducing noise and improving air outlet efficiency.

[0091] Specifically, Figure 3 As shown, the position of the maximum deflection of the center line 201 of the cross section of the blade 20 does not coincide with the position of the maximum thickness.

[0092] In a preferred embodiment, the distance C between the position of the maximum deflection of the center line 201 of the cross section and the inner edge 21 and the chord length L of the blade 20 satisfy C / L=0.42.

[0093] See also Figure 5 and Figure 6 In some embodiments, the inlet angle of the blade 20 is β1, satisfying 51°≤β1≤61°.

[0094] In this way, by setting the inlet angle β1 of the blade 20 within a reasonable range, the airflow is ensured to smoothly enter and exit the impeller 100, the resistance loss is reduced, the air volume is increased, the static pressure is increased, and the noise can be further reduced.

[0095] Specifically, the inlet angle β1 is the angle of the gas relative to the surface normal of the impeller 100 when entering the impeller 100. For example, the inlet angle of the blade 20 may be 51°, 53°, 56°, 57.8°, 60°, or 61°. In a preferred embodiment, β1=56°.

[0096] See also Figure 5 and Figure 6 In some embodiments, the outlet angle of the blade 20 is β2, satisfying 136°≤β2≤146°.

[0097] In this way, by setting the outlet angle β2 of the blade 20 within a reasonable range, the rotation speed and physical size of the impeller 100 can be reduced, the weight can be reduced, and the noise can be reduced while the flow rate and total pressure are the same.

[0098] Specifically, the outlet angle β2 is the angle between the extension line of the outer edge 22 of the blade 20 to the periphery and the opposite direction of the tangent line of the rotation direction of the outer edge 22. Exemplarily, the outlet angle β2 of the blade 20 can be 136°, 137°, 139°, 142°, 145.5°, 146°. In a preferred embodiment, β2=141°.

[0099] In this embodiment, the outlet angle is an obtuse angle, and the impeller 100 is a forward centrifugal impeller 100. Therefore, compared with the backward impeller 100 used in most centrifugal fans 1000, under the condition of the same flow rate and total pressure, the rotation speed and physical size of the impeller 100 are smaller, which is conducive to reducing noise.

[0100] See also Figure 1 and Figure 2 In some embodiments, the number of blades 20 located on the same side of the wheel disk 10 is Z, satisfying 41≤Z≤61.

[0101] In this way, by setting the number of blades 20 within a reasonable range, the airflow can be generated and accelerated more effectively, thereby improving the air outlet efficiency of the impeller 100.

[0102] Specifically, a plurality of blades 20 are arranged at equal intervals along the circumference of the wheel disc 10 on the same axial side of the wheel disc 10. For example, the number of blades 20 located on the same side of the wheel disc 10 may be 41, 43, 52, 57, 59, or 61.

[0103] Optionally, two groups of blades 20 arranged along the circumference of the wheel disc 10 may be provided on both sides of the wheel disc 10 in the axial direction. The number of blades 20 located on both sides of the wheel disc 10 may be the same or different.

[0104] Optionally, the blades 20 on both sides of the wheel disc 10 in the thickness direction may be arranged in a staggered manner in the circumferential direction. In other embodiments, the number of blades 20 on both sides of the wheel disc 10 in the thickness direction is the same and they are aligned one by one along the axial direction of the impeller 100 .

[0105] In a preferred embodiment, the combination Figure 3 , the number of blades 20 located on the same side of the disk 10 is Z=51, and the maximum deflection f, inlet angle β1, outlet angle β2, distance C between the position of maximum deflection and the inner edge 21, and chord length L of the cross-sectional midline 201 of each blade 20 located on the same side of the disk 10 all satisfy: f / L=0.219; C / L=0.42; β1=56°; β2=141°. At the same time, the maximum thickness D1, minimum thickness D2, distance A between the maximum thickness position and the inner edge 21, and distance B between the minimum thickness position and the inner edge 21 of the blade 20 satisfy: D1 / L=0.15; D2 / D1=0.428; A / L=0.27; B / L=0.9.

[0106] In this example, see Figure 7 , the noise spectrum of the impeller 100 is lower than that of the conventional impeller 100 in the noise decibel value of each frequency band, and the peak value of the noise decibel is significantly reduced. Usually, the highest frequency of the noise of the impeller 100 is around 1000HZ. The impeller 100 of the embodiment of the present application has a better noise reduction effect in the noise frequency band below 1000HZ. In addition, the curve of the noise spectrum of the impeller 100 of the embodiment of the present application in the peak band is relatively smooth, and the noise decibel value changes relatively slowly with the frequency, indicating that the impeller 100 is not easy to produce harsh sounds during rotation, further optimizing the user experience.

[0107] See also Figure 8-Figure 10 In some embodiments, the impeller 100 further includes an end ring 30, and each of the plurality of blades 20 extends from the wheel disk 10 to the end ring 30. Along the extension trajectory of the blade 20, the cross-sectional shape of the blade 20 perpendicular to the axial direction of the wheel disk 10 remains unchanged.

[0108] In this way, as each blade 20 extends from the wheel disc 10 to the end ring 30 , the cross-sectional shape of the blade 20 along the direction perpendicular to the axial direction of the wheel disc 10 remains unchanged, so that the end ring 30 supports the blade 20 and improves the structural strength.

[0109] Specifically, the wheel disc 10, the impeller 100 and the end ring 30 are fixedly connected. The wheel disc 10, the impeller 100 and the end ring 30 can be integrally formed, or they can be manufactured separately and then assembled by welding, threading, etc. The rotation center O of the impeller 100 can be located at the geometric center of the wheel disc 10, and the blades 20 are located at the radial edge of the wheel disc 10 and extend roughly along the radial direction of the wheel disc 10. The inner edge 21 of the blade 20 is connected to the wheel disc 10, and the outer edge 22 is connected to the end ring 30.

[0110] The end ring 30 surrounds the end of the blade 20 along the circumference of the impeller 100, and the end ring 30 can be coaxial with the wheel disc 10. In the embodiment of the present application, the circumference of the impeller 100 and the radial direction of the impeller 100 (such as Figure 10-Figure 14 X direction as shown), the axial direction of the impeller 100 (as shown Figure 10-Figure 14 The Y direction shown in the figure is in one-to-one correspondence with the circumferential direction of the end ring 30, the radial direction of the end ring 30, and the axial direction of the end ring 30.

[0111] In the related art, in order to facilitate the manufacture of an impeller 100 with a complex shape, the impeller 100 can be made of plastic as a whole. However, the structural strength of the impeller 100 made of plastic is not as good as that of a metal structure, and during the injection molding process, the edge of the impeller 100, that is, the end ring 30, is prone to shrinkage due to uneven cooling and heat dissipation, further resulting in a decrease in structural strength.

[0112] See also Figure 10-Figure 14 In some embodiments, the end ring 30 protrudes from the blade 20 in the radial direction of the impeller 100 , and the end ring 30 includes a base ring 31 and a protrusion 32 protruding outward from the base ring 31 in the radial direction of the impeller 100 , and the protrusion 32 and the base ring 31 together form a groove 33 .

[0113] In this way, by providing the base ring 31 and the protrusion 32 protruding outward from the base ring 31 along the radial direction of the impeller 100, the overall thickness of the end ring 30 is increased, thereby further improving the structural strength of the end ring 30. The protrusion 32 and the base ring 31 together form a groove 33, and the thickness of the end ring 30 is partially thinned, thereby avoiding to a certain extent the shrinkage defect of the end ring 30 due to excessive material thickness, and further preventing the reduction of structural strength due to shrinkage.

[0114] When the impeller 100 rotates, an airflow is formed which enters in the axial direction and is discharged in the radial direction (eg Fig.10 However, the airflow discharged in the radial direction of the impeller 100 will partially generate reverse airflow, reducing the air discharge efficiency of the impeller 100. In the impeller 100 of the embodiment of the present application, the end ring 30 is provided with a protrusion 32 protruding in the radial direction of the impeller 100, thereby blocking the reverse airflow (such as the airflow w) from the outer peripheral side 101 of the impeller 100 to the rotation center O of the impeller 100. Fig.10The airflow v) shown improves the air outlet efficiency and the stability of the impeller 100.

[0115] The end ring 30 is disposed at one end of the blade 20 away from the wheel disc 10, and the end ring 30 wraps around the outer peripheral side 101 of the impeller 100. The end ring 30 forms a protrusion 32 protruding outward in the radial direction of the impeller 100 on the base ring 31, and the protrusion 32 and the base ring 31 together form a groove 33, so that the outer peripheral side 101 of the impeller 100 forms an uneven surface, interrupting the flow path of the reverse airflow v along the surface of the protrusion 32, and part of the reverse airflow v is reflected in the groove 33 (such as Fig.11 As shown by the solid arrow, the reflected airflow can affect the reverse airflow v of other parts, thereby reducing the reverse backflow v returning to the inner circumference of the impeller 20. Therefore, the groove 33 is conducive to reducing the backflow of the airflow, thereby improving the air outlet performance and reducing noise.

[0116] See also Figure 10-Figure 14 In some embodiments, the base ring 31 includes a circular surface 311 and a first side surface 312 connected to the circular surface 311, the circular surface 311 is concentrically arranged with the impeller 100, the protrusion 32 protrudes from the circular surface 311, and the protrusion 32 and the circular surface 311 together form a groove 33.

[0117] In this way, the annular surface 311 is arranged concentrically with the impeller 100, the protrusion 32 protrudes from the annular surface 311, and the protrusion 32 and the annular surface 311 together form a groove 33, so that the thickness of the end ring 30 is thinner at the groove 33 and thicker at the protrusion 32, so that the end ring 30 is not prone to shrinkage defects during the molding process. In addition, the top surface of the annular surface 311 and the protrusion 32 forms the surface of the outer peripheral side 101 of the impeller 100. Compared with the flat outer peripheral surface, the protrusion 32 can block the reverse airflow to a certain extent.

[0118] Specifically, combined Figure 8 The base ring 31 surrounds the impeller 100 along the circumferential direction of the impeller 100, the annular surface 311 and the first side surface 312 form a part of the surface of the outer peripheral side 101 of the impeller 100, the annular surface 311 faces the outer side of the impeller 100 along the radial direction of the impeller 100, and the first side surface 312 faces the outer side or the inner side of the impeller 100 along the axial direction of the impeller 100. The protrusion 32 protrudes from the annular surface 311, the annular surface 311 forms the groove bottom surface of the groove 33, and the protrusion 32 forms the groove wall of the groove 33.

[0119] In some embodiments, in combination Fig.14, the impeller 100 is applied to the centrifugal fan 1000 and is accommodated in the volute 200. The air outlet of the volute 200 is arranged along the radial direction of the impeller 100, and the volute tongue 221 of the volute 200 (the connection between the air outlet and the spiral line of the volute 200) can form an arc transition. The volute tongue 221 is opposite to the outer peripheral side 101 of the end ring 30, that is, the uneven surface formed by the protrusion 32 and the groove 33. In the related art, the airflow discharged from the outer peripheral side 101 of the impeller 100 to the air outlet along the radial direction of the impeller 100 is easy to collide with the volute tongue 221 (the collision airflow is such as Fig.11 ), causing noise.

[0120] Combination Fig.11 In the impeller 100 of the embodiment of the present application, the groove 33 is formed by the protrusion 32 and the base ring 31, and the distance between the surface of the outer peripheral side 101 of the impeller 100 and the volute tongue 221 is partially increased, thereby reducing the impact of the airflow on the volute tongue 221, thereby reducing the noise. In addition, since the relative distance between the groove 33 and the volute tongue 221 is large, and the distance between the protrusion 32 and the volute tongue 221 is small, the airflow from different areas of the outer peripheral side 101 of the end ring 30 impacts the volute tongue 221 with a time difference, thereby reducing the noise generated by the collision at the same time.

[0121] See also Fig.10 In some embodiments, there are multiple protrusions 32 , and the multiple protrusions 32 are arranged at intervals along the axial direction of the impeller 100 . Two adjacent protrusions 32 and the annular surface 311 together form a groove 33 .

[0122] In this way, multiple protrusions 32 are arranged at intervals along the axial direction of the impeller 100, and two adjacent protrusions 32 and the annular surface 311 together form a groove 33, so that the outer peripheral side 101 of the impeller 100 forms an uneven surface, reducing the formation of vortices on the surface of the outer peripheral side 101 of the impeller 100, which is beneficial to reduce noise and improve energy efficiency.

[0123] Specifically, the number of protrusions 32 is multiple means that the number of protrusions 32 is two or more, for example, the number of protrusions 32 can be two, three, five or more. The number of protrusions 32 can be an even number, and the interval between every two adjacent and spaced protrusions 32 forms a groove 33.

[0124] In other embodiments, the number of protrusions 32 may be an odd number, and a groove 33 is formed between every two adjacent and spaced protrusions 32, and the two protrusions 32 closest to the edge of the annular surface 311 along the axial direction of the impeller 100 may respectively form two grooves 33 with the annular surface 311 at the edge.

[0125] See also Fig.10In some embodiments, the number of the protrusions 32 is two.

[0126] In this way, the two protrusions 32 are arranged at intervals along the axial direction of the impeller 100 and form a groove 33 together with the annular surface 311, so that the cross-section of the end ring 30 is approximately in the shape of a "concave" character, so that the two protrusions 32 can block the reverse airflow and improve the air outlet efficiency.

[0127] In addition, in some embodiments, the radial circumferential surface of the end ring 30 forms a convex-concave-convex undulating profile opposite to the inner surface of the volute 200, and the impact of the airflow discharged from the outer circumferential side 101 of the impeller 100 on the volute tongue 221 is spaced apart due to the uneven distance from the circumferential surface of the end ring 30 to the volute tongue 221, and the impact is relatively gentle at positions with a larger distance, thereby reducing noise.

[0128] Please continue reading Fig.10 In some embodiments, the protrusion 32 includes a second side surface 321 , and the second side surface 321 is arranged flush with the first side surface 312 .

[0129] In this way, by arranging the second side surface 321 flush with the first side surface 312 , the axial end surface of the end ring 30 forms a continuous plane, so that the axial end structure of the end ring 30 is more regular and stable, and is easy to manufacture.

[0130] Specifically, the base ring 31 is coaxial with the impeller 100, the annular surface 311 is the end surface of the base ring 31 facing the outside of the impeller 100 along the radial direction of the impeller 100, and the first side surface 312 is the two side end surfaces of the base ring 31 in the axial direction. The second side surface 321 is the surface where the protrusion 32 is connected to the two side ends of the base ring 31 in the axial direction, and the second side surface 321 extends in the radial direction of the impeller 100 and faces the outside or inside of the impeller 100 in the axial direction of the impeller 100. The first side surface 312 and the second side surface 321 are connected and flush.

[0131] Exemplarily, a plurality of protrusions 32 are arranged at intervals on the annular surface 311 along the axial direction of the impeller 100, and at least one protrusion 32 is arranged on the edge of the annular surface 311 along the axial direction of the impeller 100. The second side surface 321 of the protrusion 32 located at the edge of the annular surface 311 along the axial direction of the impeller 100 is flush with the first side surface 312 of the edge of the annular surface 311 on the same side.

[0132] For another example, the number of the protrusion 32 is one, the protrusion 32 is located at the axial edge of the annular surface 311, and the second side surface 321 of the protrusion 32 is flush with the first side surface 312 located at the same side edge.

[0133] See also Fig.10 In some embodiments, the two protrusions 32 have the same size along the axial direction of the impeller 100 , and / or the two protrusions 32 have the same size protruding from the annular surface 311 .

[0134] In this way, the thickness and width of the protrusion 32 are relatively uniform, thereby reducing the risk of shrinkage, improving the structural strength, and facilitating molding.

[0135] Specifically, the cross section of the protrusion 32 perpendicular to the circumference of the impeller 100 may be roughly square. The two protrusions 32 are arranged at intervals along the axial direction of the impeller 100, that is, one of the protrusions 32 is close to the wheel disc 10, and the other is relatively far away from the wheel disc 10. The two protrusions 32 can be located at the edges of the end ring 30 close to and away from the wheel disc 10, respectively. The two protrusions 32 have equal sizes along the axial direction of the impeller 100, so that the two-part structure of the end ring 30 on both sides of the center line 201 along the axial direction of the impeller 100 is relatively balanced.

[0136] In some embodiments, the protrusions 32 protrude outward from the annular surface 311 along the radial direction of the impeller 100 , and the two protrusions 32 have the same size protruding from the annular surface 311 , that is, the protrusions 32 have the same size along the radial direction of the impeller 100 .

[0137] In some embodiments, the two protrusions 32 are respectively located on the two side edges of the annular surface 311 along the axial direction of the impeller 100, the two protrusions 32 have equal sizes along the axial direction of the impeller 100, and the two protrusions 32 protrude from the annular surface 311 by equal sizes, so that the structure of the end ring 30 on both sides of the axial center line 201 of the impeller 100 is symmetrically distributed.

[0138] See also Fig.12 In some embodiments, the number of the protrusion 32 is one, and the protrusion 32 is located in the middle of the annular surface 311 in the axial direction. The protrusion 32 forms grooves 33 with the annular surface 311 on both sides of the axial direction of the impeller 100.

[0139] In this way, by setting a protrusion 32 at the middle position of the annular surface 311 along the axial direction, two grooves 33 are formed on both sides of the protrusion 32 along the axial direction, so that the cross-section of the end ring 30 is approximately in the shape of a "convex" character, which is beneficial to optimizing the airflow guide path on the surface of the end ring 30, thereby reducing noise and improving air outlet efficiency.

[0140] Specifically, the outer circumferential surface of the end ring 30 has concave-convex-concave undulations in sequence along the axial direction of the impeller 100 , which increases the number of times the airflow on the outer circumferential surface of the end ring 30 is interrupted and further reduces the airflow returning to the inner circumference of the impeller 100 .

[0141] See also Fig.12 In some embodiments, the grooves 33 located on both sides of the protrusion 32 have the same size.

[0142] In this way, the grooves 33 on both sides of the protrusion 32 have the same size, so that the structure of the end ring 30 has a certain symmetry, which is convenient for molding and has good structural stability.

[0143] Specifically, along the axial direction of the impeller 100, the protrusion 32 is located in the middle of the annular surface 311, dividing the annular surface 311 into two equal-sized parts. The two side surfaces of the protrusion 32 along the axial direction of the impeller 100 respectively form two grooves 33 with the two parts of the annular surface 311, and the two side surfaces of the protrusion 32 along the axial direction have the same size, and the axial size and radial size of the two grooves 33 are the same.

[0144] See also Fig.13 In some embodiments, the number of the protrusion 32 is one, and the protrusion 32 is located at the axial edge of the annular surface 311 .

[0145] In this way, by providing a protrusion 32 on the axial edge of the annular surface 311 , the molding of the end ring 30 is facilitated.

[0146] Specifically, the protrusion 32 may be located at an edge of the annular surface 311 close to the wheel disc 10, and a surface of the protrusion 32 facing the wheel disc 10 may be flush with a side surface of the base ring 31 facing the wheel disc 10. The edge of the protrusion 32 facing away from the wheel disc 10 and the annular surface 311 together limit the formation of the groove 33. In this embodiment, the cross section of the end ring 30 is approximately a transverse "L" shape.

[0147] See also Figure 10-13 In some embodiments, along the radial direction of the impeller 100 , the size of the base ring 31 is larger than the size of the protrusion 32 .

[0148] In this way, by making the size of the base ring 31 larger than the size of the protrusion 32 along the radial direction of the impeller 100 , the thickness of the portion of the end ring 30 that completely surrounds the impeller 100 is thicker, thereby improving the overall strength of the end ring 30 .

[0149] Specifically, along the radial direction of the impeller 100, the base ring 31 and the protrusion 32 are sequentially located at the periphery of the outer peripheral side 101 of the blade 20. The size of the base ring 31 is slightly larger than the size of the protrusion 32. For example, the size of the base ring 31 along the radial direction of the impeller 100 is 2.5 mm, and the size of the protrusion 32 along the radial direction of the impeller 100 is 2.1 mm. For another example, the size of the base ring 31 along the radial direction of the impeller 100 is 4.5 mm, and the size of the protrusion 32 along the radial direction of the impeller 100 is 3.3 mm.

[0150] See also Figure 12-14 In some embodiments, the dimension of the protrusion 32 protruding from the annular surface 311 is H1, 2mm

[0151] ​In this way, by setting the dimension H1 of the protrusion 32 protruding from the annular surface 311 within a reasonable range, the overall dimension of the end ring 30 is kept not too thick while blocking the reverse airflow, thereby reducing the overall weight of the impeller 100, optimizing the aerodynamic characteristics of the impeller 100, and facilitating molding.

[0152] Specifically, the dimension H1 of the protrusion 32 protruding from the annular surface 311 is also the dimension of the protrusion 32 along the radial direction of the impeller 100. For example, the dimension H1 of the protrusion 32 protruding from the annular surface 311 may be 2.2 mm, 3.4 mm, 4.9 mm, 5.7 mm, or 5.99 mm.

[0153] In some embodiments, Figure 10-12 As shown, the protrusion 32 protrudes from the annular surface 311 and the side surface of the protrusion 32 along the axial direction of the impeller 100 and the annular surface 311 jointly define a groove 33. In this embodiment, the dimension H1 of the protrusion 32 protruding from the annular surface 311 is the same as the dimension H3 of the groove 33 along the radial direction of the impeller 100.

[0154] In other embodiments, Fig.14 As shown, the protrusion 32 includes a connecting section 322 and an extending section 323, the connecting section 322 extends from the annular surface 311 along the radial direction of the impeller 100, the extending section 323 extends from the connecting section 322 along the axial direction of the impeller 100, and the connecting section 322, the extending section 323 and the annular surface 311 together form a groove 33. In this embodiment, the dimension H1 of the protrusion 32 protruding from the annular surface 311 is the same as the dimension of the connecting section 322 and the extending section 323 along the radial direction of the impeller 100, and is larger than the dimension H3 of the groove 33 along the radial direction of the impeller 100.

[0155] See also Figure 12-14 In some embodiments, along the axial direction of the impeller 100, the size of the protrusion 32 is H2, 0mm<H2<6mm.

[0156] In this way, by setting the dimension H2 of the protrusion 32 along the axial direction of the impeller 100 within a reasonable range, the ratio of the protrusion 32 to the groove 33 in the axial direction of the impeller 100 is conducive to optimizing the airflow guide path of the outer peripheral side 101 of the impeller 100, thereby improving the air outlet efficiency and reducing noise.

[0157] Specifically, the dimension H2 of the protrusion 32 along the axial direction of the impeller 100 may be 0.1 mm, 1.6 mm, 2.4 mm, 3.7 mm, 4.5 mm, 5 mm, or 5.9 mm. The dimension H2 of the protrusion 32 along the axial direction of the impeller 100 does not exceed the dimension of the base ring 31 along the axial direction of the impeller 100.

[0158] In some embodiments, Figure 10-12As shown, the protrusion 32 protrudes from the annular surface 311 and the side surface of the protrusion 32 along the axial direction of the impeller 100 and the annular surface 311 jointly define a groove 33. In this embodiment, the dimension H2 of the protrusion 32 along the axial direction of the impeller 100 is smaller than the dimension of the base ring 31 along the axial direction of the impeller 100.

[0159] See also Fig.14 In some embodiments, the base ring 31 includes a circular surface 311 and a first side surface 312 connected to the circular surface 311, the circular surface 311 is concentrically arranged with the impeller 100, the protrusion 32 includes a connecting section 322 and an extending section 323, the connecting section 322 extends from the circular surface 311 along the radial direction of the impeller 100, the extending section 323 extends from the connecting section 322 along the axial direction of the impeller 100, the connecting section 322, the extending section 323 and the circular surface 311 together form a groove 33, and the notch of the groove 33 faces the first side surface 312.

[0160] In this way, the connecting section 322 extends from the annular surface 311 along the radial direction of the impeller 100, and the extending section 323 extends from the connecting section 322 along the axial direction of the impeller 100. The connecting section 322, the extending section 323 and the annular surface 311 jointly form a groove 33, and the notch of the groove 33 faces the first side surface 312, so that the connecting section 322 and the base ring 31 can block the reverse airflow and improve the air outlet efficiency of the impeller 100. In addition, the thickness of the end ring 30 is thinned in the area where the groove 33 is formed, which is beneficial to reduce shrinkage defects during the molding process.

[0161] Specifically, the annular surface 311 surrounds the end of the blade 20 away from the impeller 10 and is located on the side away from the axis in the radial direction of the impeller 100. The first side surface 312 is a side surface of the base ring 31 away from the impeller 10 in the axial direction of the impeller 100. The connecting section 322 can extend from the edge of the annular surface 311 close to the impeller 10. The connecting section 322 extends in the radial direction of the impeller 100, and the extension section 323 extends from the connecting section 322 in the axial direction of the impeller 100, and the connecting section 322 and the extension section 323 form a 90° angle.

[0162] The bottom surface of the groove 33 and the notch of the groove 33 are opposite to each other along the axial direction of the impeller 100. The side surface of the extension section 323 facing the base ring 31 and the annular surface 311 are opposite to and spaced apart from each other along the radial direction of the impeller 100, and the side surface of the extension section 323 facing the base ring 31 and the annular surface 311 respectively form the groove walls on both sides of the groove 33.

[0163] Optionally, the end of the extension section 323 extending in the axial direction of the impeller 100 is flush with the first side surface 312. In this embodiment, the dimension H2 of the protrusion 32 in the axial direction of the impeller 100 is equal to the dimension of the base ring 31 in the axial direction of the impeller 100.

[0164] See also Figure 12-14In some embodiments, the radial dimension of the groove 33 along the impeller 100 is H3, 2mm<H3<6mm.

[0165] In this way, by setting the radial dimension H3 of the groove 33 along the impeller 100 within a reasonable range, the reverse airflow can be reasonably blocked, the air outlet efficiency can be improved, and shrinkage defects can be reduced.

[0166] Specifically, the dimension H3 of the groove 33 along the radial direction of the impeller 100 may be 2.1 mm, 3.4 mm, 3.7 mm, 4.5 mm, 5.2 mm, or 5.8 mm. The dimension H3 of the groove 33 along the radial direction of the impeller 100 matches the dimension H1 of the protrusion 32 along the radial direction of the impeller 100. For example, see Fig.10 The protrusion 32 protrudes outward from the annular portion along the axial direction of the impeller 100 , and the protrusion 32 and the annular surface 311 jointly define a groove 33 , and a radial dimension H3 of the groove 33 along the impeller 100 is equal to a radial dimension H1 of the protrusion 32 along the impeller 100 .

[0167] For example, see Fig.14 The protrusion 32 includes a connecting section 322 and an extending section 323. The connecting section 322 extends from the annular surface 311 along the radial direction of the impeller 100. The extending section 323 extends from the connecting section 322 along the axial direction of the impeller 100. The connecting section 322, the extending section 323 and the annular surface 311 together form a groove 33. The radial dimension H3 of the groove 33 along the impeller 100 is equal to the difference between the radial dimension H1 of the protrusion 32 along the impeller 100 and the radial dimension of the extending section 323 along the impeller 100.

[0168] See also Figure 12-14 In some embodiments, the dimension of the groove 33 along the axial direction of the impeller 100 is H4, 4mm<H4<8mm.

[0169] In this way, by setting the dimension H4 of the groove 33 along the axial direction of the impeller 100 within a reasonable range, the ratio of the protrusion 32 to the groove 33 in the axial direction of the impeller 100 is conducive to optimizing the airflow guide path of the outer peripheral side 101 of the impeller 100, thereby improving the air outlet efficiency and reducing noise.

[0170] Specifically, the dimension H4 of the groove 33 along the axial direction of the impeller 100 can be 4.08 mm, 4.7 mm, 5.3 mm, 6 mm, 6.2 mm, 7.5 mm, or 7.9 mm. The dimension H4 of the groove 33 along the axial direction of the impeller 100 matches the dimensions (H2, H4) of the protrusion 32 and the end ring 30 along the axial direction of the impeller 100. For example, see Fig.10The protrusion 32 protrudes outward from the annular portion along the axial direction of the impeller 100, and the protrusion 32 and the annular surface 311 jointly define the groove 33, and the sum of the dimensions of all the grooves 33 and the protrusion 32 along the axial direction of the impeller 100 is equal to the axial dimension of the end ring 30 along the axial direction of the impeller 100.

[0171] For example, see Fig.14 The protrusion 32 includes a connecting section 322 and an extending section 323. The connecting section 322 extends from the annular surface 311 along the radial direction of the impeller 100. The extending section 323 extends from the connecting section 322 along the axial direction of the impeller 100. The connecting section 322, the extending section 323 and the annular surface 311 together form a groove 33. The dimension H4 of the groove 33 along the axial direction of the impeller 100 is equal to the difference between the dimension H2 of the protrusion 32 along the axial direction of the impeller 100 and the dimension of the connecting section 322 along the axial direction of the impeller 100.

[0172] See also Figure 12-14 In some embodiments, along the radial direction of the impeller 100 , the dimension of the end ring 30 is H5, 4mm<H5<8mm.

[0173] In this way, by setting the radial dimension H5 of the end ring 30 along the impeller 100 within a reasonable range, the reverse airflow is effectively blocked and the air outlet efficiency is improved.

[0174] Specifically, the radial dimension H5 of the end ring 30 along the impeller 100 may be 4.01 mm, 4.6 mm, 5.2 mm, 5.7 mm, 6.3 mm, 7 mm, or 7.88 mm. The radial dimension H5 of the end ring 30 along the impeller 100 is equal to the sum of the radial dimensions of the protrusion 32 and the base ring 31 along the impeller 100.

[0175] See also Figure 12-14 In some embodiments, along the axial direction of the impeller 100 , the dimension of the end ring 30 is H6, 4mm<H6<12mm.

[0176] In this way, by setting the dimension of the end ring 30 along the axial direction H6 of the impeller 100 within a reasonable range, the end ring 30 has sufficient structural strength to protect and support the blades 20 .

[0177] Specifically, the dimension H6 of the end ring 30 along the axial direction of the impeller 100 may be 4.03 mm, 5.4 mm, 6.1 mm, 7.45 mm, 8 mm, 9.2 mm, 10.5 mm, or 11.7 mm.

[0178] See also Figure 8 and Fig. 9 In some embodiments, the edge of the end ring 30 facing away from the wheel disk 10 is flush with the edge of the blade 20 .

[0179] In this way, the edge of the end ring 30 facing away from the wheel disc 10 is flush with the edge of the blade 20 , thereby facilitating molding, and helping to improve the impact resistance of the end ring 30 and enhance the protection of the blade 20 .

[0180] Specifically, the edge of the end ring 30 away from the wheel disc 10 is flush with the edge of the blade 20 away from the wheel disc 10. Two groups of blades 20 may be provided on both sides of the wheel disc 10 in the thickness direction, and the ends of the two groups of blades 20 away from the wheel disc 10 are sleeved in the end ring 30 and fixedly connected to the end ring 30. The edges of the multiple blades 20 on the same side of the wheel disc 10 in the thickness direction along one side of the axial direction of the impeller 100 are flush with each other and connected to the wheel disc 10, and the edges on the side away from the wheel disc 10 are also flush with each other. The end ring 30 is flush with the edges of the multiple blades 20 on the same side, so that the impeller 100 forms flat edges on both sides along the axial direction.

[0181] See also Figure 8 and Fig. 9 In some embodiments, blades 20 and end rings 30 are provided on both sides of the wheel disc 10 in the thickness direction.

[0182] In this way, by arranging blades 20 and end rings 30 on both sides of the wheel disc 10 in the thickness direction, the air output is increased, the structural support is enhanced, and the structural stability is ensured.

[0183] Specifically, a plurality of blades 20 are arranged at intervals along the circumference of the wheel disc 10 on both sides of the wheel disc 10 in the thickness direction, and the blades 20 on both sides are connected to the wheel disc 10 at one end in the length direction and connected to the end ring 30 at the other end. The end ring 30 at least partially covers the end of the blade 20 away from the wheel disc 10 and surrounds the impeller 100. The blades 20 arranged on both sides of the wheel disc 10 can be staggered in sequence along the circumference of the wheel disc 10.

[0184] See also Fig.15 In a second aspect, the centrifugal fan 1000 provided in the present application includes a volute 200 and an impeller 100 of any of the above-mentioned embodiments, and the impeller 100 is accommodated in the volute 200 .

[0185] The centrifugal fan 1000 of the embodiment of the present application has all the beneficial effects of the impeller 100 of the embodiment of the present application because it includes the impeller 100 of any of the above-mentioned embodiments.

[0186] Specifically, the impeller 100 generates airflow by rotating, and air or other gases are sucked into the volute 200 , and the air or other gases are discharged from the volute 200 after being accelerated by the impeller 100 .

[0187] The centrifugal fan 1000 of the embodiment of the present application can be applied to a HVAC system 2000. For example, the centrifugal fan 1000 can be used for a duct air conditioner. For example, the centrifugal fan can be used for a vertical air conditioner cabinet. The impeller 100 is a rotating component in an air conditioner (including an indoor unit and an outdoor unit). The rotation of the impeller 100 can be driven by a motor. The volute 200 can be used to guide airflow and improve gas flow efficiency. In the air conditioner, the volute 200 can be a housing portion of the centrifugal fan 1000.

[0188] See also Fig. 9 and Fig.15 In some embodiments, the volute 200 includes two side panels 210 and a surrounding panel 220 that are arranged opposite to each other. The surrounding panel 220 is arranged between the two side panels 210, and the surrounding panel 220 extends circumferentially to form a profile line of the volute 200. The two side panels 210 that are arranged opposite to each other are respectively connected to the two sides of the surrounding panel 220, and at least one side panel 210 is provided with an air inlet; wherein at least one side panel 210 is detachably connected to the surrounding panel 220, at least one side panel 210 is made of a first material, and the surrounding panel 220 is made of a second material, and the density of the first material is less than the density of the second material.

[0189] It should be noted that when the side panels 210 and the apron 220 are both made of a material with a higher density, the weight of the volute 200 is relatively large, which makes the transportation cost and installation cost of the volute 200 relatively high. When the side panels 210 and the apron 220 are both made of a material with a lower density, the weight of the volute 200 is relatively small, but since the manufacturing process of the material with a lower density is usually complicated, the manufacturing cost of the volute 200 is relatively high.

[0190] Therefore, under the same volume, by making at least one side panel 210 of the first material with a lower density, the volute 200 can take into account the advantages of light weight and low cost, that is, when the weight is small, the transportation cost, installation cost and manufacturing cost of the volute 200 are low. In addition, since the enclosure 220 is made of the second material with a higher density, the overall structural strength of the volute 200 can still meet the requirements. By providing an air inlet on the side panel 210, the airflow entering the volute 200 can be more effectively controlled and guided, so that the air flow inside the volute 200 can be increased, thereby improving the heat dissipation efficiency.

[0191] In addition, the detachable connection design allows the side plate 210 and the shroud 220 of the volute to be produced separately and then assembled. This modular production method can improve production efficiency and reduce the complexity and cost of the production process. At the same time, the detachable design also facilitates later maintenance and replacement, improving assembly efficiency. For example, the detachable design of the side plate 210 and the shroud 220 can facilitate the installation and removal of the impeller 100.

[0192] Specifically, the side plates 210 may be flat plate structures constituting both sides of the volute 200. The side plates 210 may be used to provide support and enclosure. The two side plates 210 may be arranged opposite to each other along the length direction and the width direction of the volute 200. As an example, the two side plates 210 may be spaced apart from each other, and the two side plates 210 may be arranged opposite to each other along the width direction of the volute 200.

[0193] The enclosure 220 can be used to fix and connect the two side panels 210. The connection between the enclosure 220 and the side panels 210 can be a detachable connection such as a threaded connection or a snap connection.

[0194] Density refers to the mass of a material per unit volume. The density of the side panel is less than that of the enclosure panel, which means that the material used for the side panel 210 is lighter than that of the enclosure panel 220. The first material may be a material with a lower density, such as ABS (Acrylonitrile Butadiene Styrene), polypropylene, or carbon fiber reinforced plastic. The second material may be a material with a higher density, such as stainless steel or aluminum plate.

[0195] The air inlet 211 refers to an opening provided on the side plate 210, and the air inlet 211 can serve as an entrance for airflow to enter the interior of the volute. The shape of the air inlet 211 can be a regular shape such as a circle or a square, or an irregular shape. One air inlet 211 can be provided on the side plate 210. The air inlet 211 can be provided in the middle part of the side plate 210. A plurality of air inlets 211 can also be provided on the side plate 210. The number of air inlets 211 can be two, three, four or even more.

[0196] See also Fig.15 In some embodiments, the enclosure 220 includes a volute tongue 221, and a recessed groove 222 is recessed from the surface of the volute tongue 221 away from the end ring 30, and the groove 33 has a notch facing the recessed groove 222.

[0197] In this way, by setting the groove 222, the minimum gap between the volute tongue 221 and the outer edge of the impeller 100 can be guaranteed, and at the same time, the impact of the airflow on the volute tongue 221 can be reduced, thereby optimizing the flow field inside the volute 200, and effectively suppressing the airflow from generating eddy currents at the volute tongue 221. While ensuring the performance of the centrifugal fan 1000, the eddy current noise of the centrifugal fan 1000 is effectively reduced, thereby improving the use comfort of the centrifugal fan 1000 and ensuring the air supply efficiency of the centrifugal fan 1000.

[0198] Specifically, the sink groove 222 can be formed by a process such as stamping. The number of the sink groove 222 can be one or more. For example, a sink groove 222 can be provided on the opposite side edges of the volute tongue 221 along the two side plates 210.

[0199] Third, see Figure 15-17 The present application provides a HVAC indoor unit 2100, and the HVAC indoor unit 2100 includes the centrifugal fan 1000 of any one of the above-mentioned embodiments.

[0200] In this way, the centrifugal fan 1000 accelerates the airflow, thereby facilitating the circulation of air and improving the heat exchange effect.

[0201] Specifically, the thickness of the blade 20 in the impeller 100 changes in a specific trend, and the blade 20 profile is optimized, thereby reducing eddy currents and high and low pressure differences, improving fan efficiency, and improving noise problems. An end ring 30 is provided at one end of the blade 20 away from the wheel disc 10. The end ring 30 forms a groove 33 with the base ring 31 through the protrusion 32, thereby improving the structural strength, avoiding the risk of shrinkage, and blocking the reverse airflow v, reducing noise, and improving wind pressure performance.

[0202] See also Fig.16 and Fig.17 In some embodiments, the HVAC indoor unit 2100 includes a first machine 300 and a second machine 400, the first machine 300 includes a first box body 310 and a centrifugal fan 1000, the centrifugal fan 1000 is arranged in the first box body 310, the second machine 400 includes a second box body 410 and a heat exchanger 420, the heat exchanger 420 is arranged in the second box body 410, and the first box body 310 and the second box body 410 are detachably connected.

[0203] In this way, the centrifugal fan 1000 cooperates with the heat exchanger 420 in the detachably connected first machine 300 and the second machine 400, thereby accelerating the circulation and heat exchange of air and improving the efficiency of the HVAC indoor unit 2100.

[0204] Specifically, the first box 310 can be detachably connected to the second box 410 by at least one of a fixing connection, a card connection, a screw connection, a riveting connection, an adhesive connection, etc. The first box 310 and the second box 410 can be arranged side by side along the width direction or the length direction of the HVAC indoor unit 2100. Exemplarily, the first box 310 and the second box 410 are both square boxes, and the first box 310 and the second box 410 are arranged side by side along the width direction. The side walls of the first box 310 and the second box 410 in the width direction are opposite, and can be fitted to each other or separated by a small gap. The centrifugal fan 1000 and the heat exchanger 420 can be separated by the walls opposite to the first box 310 and the second box 410.

[0205] Fourth, please refer to Figure 16-Figure 18The present application provides a HVAC system 2000 , which includes a HVAC indoor unit 2100 and an air-conditioning outdoor unit 2200 of any of the above-mentioned embodiments, and the air-conditioning outdoor unit 2200 is connected to the HVAC indoor unit 2100 through a pipeline 2300 .

[0206] In this way, the centrifugal fan 1000 accelerates the air circulation in the HVAC indoor unit 2100, thereby improving the heat exchange effect of the HVAC system 2000 between the indoor and outdoor.

[0207] Specifically, the air conditioner outdoor unit 2200 includes a compressor 500, a flow switching device 600, an outdoor heat exchanger 700, and an expansion valve 800. The compressor 500 compresses and discharges the sucked refrigerant. The flow switching device 600 is, for example, a four-way valve, and is a device for switching the direction of the refrigerant flow path.

[0208] The outdoor heat exchanger 700 performs heat exchange between the refrigerant and the outdoor air. The outdoor heat exchanger 700 functions as an evaporator during heating operation, exchanges heat between the low-pressure refrigerant flowing in from the refrigerant pipe and the outdoor air, and evaporates the refrigerant into gas.

[0209] The outdoor heat exchanger 700 functions as a condenser during cooling operation, and performs heat exchange between the refrigerant compressed by the compressor 500 and flowing in from the flow switching device 600 and the outdoor air, thereby condensing and liquefying the refrigerant.

[0210] A centrifugal fan 1000 may also be provided in the outdoor heat exchanger 700 to improve the efficiency of heat exchange between the refrigerant and the outdoor air. The expansion valve 800 is a throttling device that functions as an expansion valve 800 by regulating the flow rate of the refrigerant flowing in the expansion valve 800 and adjusts the pressure of the refrigerant by changing the opening.

[0211] In one example, when the HVAC system 2000 is cooling, the high-temperature and high-pressure gas refrigerant compressed and ejected by the compressor 500 flows into the outdoor heat exchanger 700 via the flow path switching device 600. The gas refrigerant that has flowed into the outdoor heat exchanger 700 is condensed by heat exchange with the outside air sent by the outdoor blower, and becomes a low-temperature refrigerant, and flows out of the outdoor heat exchanger 700.

[0212] The refrigerant flowing out of the outdoor heat exchanger 700 is expanded and decompressed through the expansion valve 800 to become a low-temperature and low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant flows into the heat exchanger 420 of the HVAC indoor unit 2100, evaporates through heat exchange with the indoor air sent by the indoor blower, becomes a low-temperature and low-pressure gas refrigerant, and flows out of the heat exchanger 420.

[0213] At this time, the indoor air cooled by the refrigerant after absorbing heat becomes conditioned air and is blown out to the air-conditioned space from the outlet of the HVAC indoor unit 2100. The gas refrigerant flowing out of the heat exchanger 420 (indoor heat exchanger) is sucked into the compressor 500 via the flow switching device 600 and compressed again. The above actions are repeated.

[0214] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0215] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above implementation methods within the scope of the present application.

Claims

1. An impeller, characterized in that: include: Roulette; and A plurality of blades, wherein the plurality of blades are arranged on the wheel disc at intervals along the circumference of the wheel disc; The blade has an inner edge and an outer edge relative to each other, the blade has a non-uniform thickness along a cross section perpendicular to the axial direction of the wheel disc, the maximum thickness of the blade is D1, the minimum thickness of the blade is D2, the chord length of the blade is L, the distance between the maximum thickness position of the blade and the inner edge is A, the distance between the minimum thickness position of the blade and the inner edge is B, and the impeller satisfies 0.1<D1 / L<0.3; 0.3<D2 / D1<0.6; 0.2<A / L<0.35; B / L≥0.

9.

2. The impeller according to claim 1, characterized in that: The blades are arranged with equal thickness from the minimum thickness position of the blades to the outer edge.

3. The impeller according to claim 1, characterized in that: The blade comprises a pressure surface and a suction surface opposite to each other, and the suction surface and the pressure surface are transitioned into a circular arc at the inner edge.

4. The impeller according to claim 1, characterized in that: The midline of the cross section is an arched curve.

5. The impeller according to claim 4, characterized in that: The maximum deflection between the center line of the cross section and the chord of the center line is f, which satisfies: 0.15<f / L<0.

25.

6. The impeller according to claim 5, characterized in that The distance between the position of the maximum deflection of the center line of the cross section and the inner edge is C, satisfying 0.38<C / l<0.

5.

7. The impeller according to claim 1, characterized in that The inlet angle of the blade is β1, which satisfies 51°≤β1≤61°.

8. The impeller according to claim 1, characterized in that The outlet angle of the blade is β2, which satisfies 136°≤β2≤146°.

9. The impeller according to claim 1, characterized in that: The number of the blades located on the same side of the wheel disc is Z, satisfying 41≤Z≤61.

10. The impeller according to claim 1, characterized in that The impeller further comprises an end ring. Each of the plurality of blades extends from the wheel disc to the end ring. Along the extension trajectory of the blade, the cross-sectional shape of the blade perpendicular to the axial direction of the wheel disc remains unchanged.

11. The impeller according to claim 10, characterized in that The end ring protrudes from the blades in the radial direction of the impeller, and comprises a base ring and a protruding portion protruding outward from the base ring in the radial direction of the impeller, wherein the protruding portion and the base ring together form a groove.

12. The impeller according to claim 10, characterized in that The blades and the end rings are arranged on both sides of the wheel disc in the thickness direction.

13. A centrifugal fan, characterized in that: include: snail shell; and The impeller according to any one of claims 1 to 12, wherein the impeller is accommodated in the volute.

14. The centrifugal fan according to claim 13, characterized in that: The volute comprises: A shroud plate, the shroud plate extending circumferentially to form a volute profile, Two side panels arranged opposite to each other are respectively connected to two sides of the enclosure, and at least one of the side panels is provided with an air inlet; Wherein, at least one of the side panels is detachably connected to the enclosure, the at least one side panel is made of a first material, and the enclosure is made of a second material, and the density of the first material is less than the density of the second material.

15. A HVAC indoor unit, characterized in that: include: The centrifugal fan as claimed in claim 13.

16. The HVAC indoor unit according to claim 15, characterized in that: The HVAC indoor unit includes a first machine and a second machine, the first machine includes a first box and the centrifugal fan, the centrifugal fan is arranged in the first box, the second machine includes a second box and a heat exchanger, the heat exchanger is arranged in the second box, and the first box is detachably connected to the second box.

17. A HVAC system, characterized in that: include: The HVAC indoor unit according to claim 15 or 16; and An air-conditioning outdoor unit is connected to the HVAC indoor unit via a pipeline.

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