Fans and electrical equipment

Abstract

The present invention proposes a fan and electrical equipment, wherein the fan comprises: an impeller, including a wheel disc, the outer surface of which is constructed as a truncated cone-shaped concave surface; a diffuser, which is coaxially arranged with the impeller, and the diffuser comprises a diffuser plate, the outer surface of which comprises a truncated cone-shaped convex surface and a first cylindrical surface spliced ​​with each other, the diameter of the end of the convex surface close to the impeller is smaller than the diameter of the end away from the impeller, and the first cylindrical surface is arranged away from the impeller relative to the convex surface; a wind cover, which is arranged on the impeller and the diffuser, and the inner surface of the wind cover comprises a truncated cone side surface and a second cylindrical surface spliced ​​with each other along the axial direction, the truncated cone side surface corresponds to the concave surface and a convex surface respectively, and the second cylindrical surface corresponds to the first cylindrical surface, so as to define the fan air duct. Through the technical solution of the present invention, the fan can operate efficiently within a wider speed range (100,000 to 150,000 revolutions).

Description

Technical Field

[0001] The present invention relates to the field of fans, and in particular to a fan and an electrical device. Background Art

[0002] The high-speed fan drives the impeller to rotate at high speed through the motor, forming a negative pressure environment in the sealed shell, sucking dust and other debris into the dust collection device, achieving a good air supply effect, but there are the following defects:

[0003] The small high-speed fans in the related technology can achieve an efficiency of 52.5% under the condition of 400W-120000rpm. High power and high speed will aggravate fluid and mechanical losses, resulting in excessive temperature rise. For example, under the condition of 500W-125000rpm, the operating efficiency will be reduced (not exceeding 50%). Summary of the invention

[0004] In order to solve at least one of the above technical problems, an object of the present invention is to provide a fan.

[0005] Another object of the present invention is to provide an electrical device.

[0006] In order to achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention provides a fan, comprising: an impeller, comprising a wheel disc, the outer surface of the wheel disc is constructed as a truncated cone-shaped concave surface, and the diameter of one end of the wheel disc is smaller than the diameter of the other end of the wheel disc; a diffuser, arranged coaxially with the impeller, the diffuser comprises a diffuser plate, one end of the diffuser plate is assembled with the other end of the wheel disc, the outer surface of the diffuser plate comprises a truncated cone-shaped convex surface and a first cylindrical surface spliced ​​to each other, the diameter of the end of the convex surface close to the impeller is smaller than the diameter of the end away from the impeller, and the first cylindrical surface is arranged away from the impeller relative to the convex surface The wind cover is coaxially arranged with the impeller and covers the impeller and the diffuser. The inner surface of the wind cover includes a truncated cone side surface and a second cylindrical surface which are axially connected to each other. The truncated cone side surface corresponds to the inner concave curved surface and the outer convex curved surface respectively, and the second cylindrical surface corresponds to the first cylindrical surface to define the fan duct. When the fan is running, the port defined by the wheel disc and the wind cover is determined as the inlet of the fan duct, and the port defined by the diffuser and the wind cover is determined as the outlet of the fan duct. The wind flows into the fan duct from the inlet, is driven by the impeller, and is diffused by the diffuser, and then flows out of the fan duct from the outlet.

[0007] In this technical solution, by limiting the external structure of the wheel disc and the external structure of the diffuser disc, combined with the inner wall of the wind hood, an air duct for the fan is enclosed. The fan with this air duct can operate efficiently within a wider speed range (100,000 to 150,000 rpm) compared to the fans in related technologies.

[0008] In the above technical solution, optionally, it also includes: a driving device, including a stator assembly, and the stator assembly is arranged relative to the outlet of the fan air duct so that the wind flowing out of the fan air duct directly blows toward the stator assembly.

[0009] In this technical solution, by arranging a stator assembly at the outlet of the fan air duct, the wind flow is blown directly to the stator assembly, thereby achieving effective cooling of the drive device, thereby improving the reliability of the motor operation.

[0010] In any of the above technical solutions, optionally, the side surface of the truncated cone includes a first side surface arranged opposite to the concave curved surface, and a second side surface arranged opposite to the convex curved surface, the first side surface is constructed as a truncated cone-shaped convex curved surface, and the second side surface is constructed as a truncated cone-shaped concave curved surface.

[0011] In this technical solution, on the basis of defining the outer structure of the wheel disc and the outer structure of the diffuser disc, the inner surface structure of the matching wind cover is further defined to achieve optimization of the mixed flow air duct, thereby improving the smoothness of the flow of the medium in the air duct, thereby improving the operating efficiency of the fan.

[0012] In any of the above technical solutions, optionally, one end of the convex curved surface close to the impeller is located on the tangential extension line of the other end of the wheel disc, or is arranged close to the tangential extension line of the other end of the wheel disc.

[0013] In this technical solution, one end of the convex curved surface close to the impeller is on or close to the tangential extension line of the other end of the wheel disc, or is higher than the tangential extension line, so that there is a smooth transition between the convex curved surface and the concave curved surface, so as to further improve the smoothness of the air supply.

[0014] In any of the above technical solutions, optionally, for any axial cross-section of the side of the cone, the angle between the tangent direction on the air inlet side and the axial direction is less than or equal to a specified angle, and the angle between the tangent direction on the air outlet side and the axial direction is less than or equal to a specified angle.

[0015] In this technical solution, by limiting the smaller angle between the tangent direction and the axial direction, the wind flow enters and exits the fan duct along the circumferential direction or nearly the circumferential direction, which helps to reduce the impact loss and separation loss of the wind flow.

[0016] The specified angle may be less than or equal to 5°.

[0017] In any of the above technical solutions, optionally, the diffuser further includes: a plurality of guide vanes, which are evenly distributed on the outer surface of the diffuser disk along the circumferential interval and extend radially outward, the guide vanes include a first section of blades arranged on the outer convex surface, and a second section of blades arranged on the first cylindrical surface, the first section of blades and the second section of blades are an integrated structure, the top surface of the first section of blades is fitted with the side surface of the cone, and the top surface of the second section of blades is fitted with the second cylindrical surface, wherein the end of the guide vane close to the wheel disk is determined as the air inlet end, and the end away from the wheel disk is determined as the air outlet end, and the air inlet end is located at the rear side of the air outlet end along the rotation direction of the impeller.

[0018] In this technical solution, the guide vanes extend to both sides to the convex curved surface and the first cylindrical surface respectively, and the wind flow is introduced into the wind duct at the rear end through the convex curved surface and the first section of blades arranged thereon, thereby improving the diffusion effect by extending the length of the diffusion path.

[0019] In any of the above technical solutions, optionally, the side surface of the air inlet end is constructed as a convex structure; when the impeller rotates, the windward side of the guide vane is determined as the pressure side, and the leeward side of the guide vane is determined as the back-pressure side, the pressure side is constructed as a convex structure, and the back-pressure side is constructed as a concave structure.

[0020] In this technical solution, the above-mentioned limitation on the curved surface of the guide vane's air inlet end, the limitation on the pressure surface and the limitation on the back pressure surface can help improve the uniformity of the airflow entering the guide vane, and can reduce the loss along the way of the airflow and the impact loss when it is discharged from the guide vane.

[0021] In any of the above technical solutions, optionally, the thickness of the guide vane gradually increases from an end close to the wheel disc to an end far away from the wheel disc.

[0022] In this technical solution, limiting the thickness of the guide vanes is also helpful in reducing wind wheel losses.

[0023] In any of the above technical solutions, optionally, in the radial direction, the top of the air inlet end is arranged close to the wind hood relative to the root of the air inlet end, and in the axial direction, the top of the air inlet end is arranged close to the impeller relative to the root of the air inlet end.

[0024] In this technical solution, the wind flow is discharged from the rotating impeller into the diffuser. By limiting the relative position relationship between the top and the root on the air inlet end, the root to the top of the air inlet end of the guide vane is extended obliquely in the direction of the air inlet, which is beneficial to improving the uniformity of the wind flow introduced into the diffuser to reduce impact losses. In addition, the air outlet direction of the guide vane is consistent with the radial direction, or has a small deviation to ensure the flow direction of the air flow at the diffuser outlet.

[0025] In any of the above technical solutions, optionally, the air outlet end is arranged close to the impeller at the free end relative to the first cylindrical surface.

[0026] In this technical solution, the guide vane is completely within the internal cavity formed by the diffuser disk and the wind cover, which can improve the uniformity of the airflow at the inlet and outlet ends of the guide vane and prevent other structural features from affecting the airflow.

[0027] In any of the above technical solutions, optionally, the number of guide vanes is 12 or 18.

[0028] In any of the above technical solutions, optionally, an annular protrusion structure is further provided at the other end of the wheel disc; a groove structure is provided on the end surface of the diffuser disc in an area corresponding to the annular protrusion structure, so that one end of the diffuser disc is assembled with the other end of the wheel disc by adapting the annular protrusion structure to the groove structure.

[0029] In this technical solution, the impeller rotates at high speed and the diffuser is fixed. By setting an annular protrusion structure and a groove structure that cooperate with each other, the annular protrusion structure and the groove structure are clearance-matched. In order to prevent leakage loss caused by the gap, the matching gap is a small gap to improve the operating efficiency of the fan. In addition, the annular protrusion structure can also be used for balancing and deweighting the impeller, thereby eliminating the setting of the impeller end balance ring to reduce the number of parts and simplify the assembly process.

[0030] In any of the above technical solutions, optionally, the impeller also includes: a plurality of blades, which are evenly distributed on the outer surface of the disk along the circumferential direction, the leading edge of the blade is arranged in front of the trailing edge of the blade along the rotation direction, the side surface of the leading edge is constructed as an outward convex surface, in the radial direction, the top of the leading edge is arranged close to the wind shield relative to the root of the leading edge, in the axial direction, the top of the leading edge is arranged close to the inlet of the fan air duct relative to the root of the leading edge, and the top of the leading edge is arranged close to the diffuser relative to one end of the disk and one end of the side surface of the cone.

[0031] In this technical solution, after the wind flow enters the wind shield, it obtains a uniform flow field and enters the flow channel formed by two adjacent blades through the leading edge of the blade to reduce the influence of the flow field change at the inlet end on the movement of the wind flow between the blades. The top of the leading edge is arranged close to the inlet of the fan air duct relative to the root of the leading edge, so that the wind flow flows into the impeller along an inclined direction, which is beneficial to control the wind volume and pressure at the leading edge to reduce the wind flow loss at the leading edge. In addition, the streamline length of the top 123 of the blade can be slightly larger than the streamline length of the root 124 of the blade, so that the wind flow has a more uniform flow state at the outlet of the impeller.

[0032] Specifically, the projection of the leading edge on a plane perpendicular to the axis direction satisfies: the root of the leading edge is located ahead of the top of the leading edge in the rotation direction.

[0033] A first connecting line is defined between the root of the leading edge and the corresponding axis, a second connecting line is defined between the top of the leading edge and the corresponding axis, and an angle between the first connecting line and the second connecting line is γ1, 0°≤γ1≤5°.

[0034] The leading edge extends roughly in the radial direction, which can reduce the fluid loss at the inlet end. The small leading angle at the top of the leading edge is conducive to fitting the fluid drainage, while ensuring the manufacturability of the impeller.

[0035] In any of the above technical solutions, optionally, the root of the trailing edge extends to the other end of the wheel disc, the top of the trailing edge is arranged axially opposite to the root of the trailing edge close to the inlet of the fan duct, the trailing edge and the outer circumferential surface of the annular protrusion structure are on the same circumferential surface, and the height of the trailing edge is less than the height of the leading edge.

[0036] A third connecting line is defined between the root of the trailing edge and the corresponding axis, a fourth connecting line is defined between the top of the trailing edge and the corresponding axis, and an angle between the third connecting line and the fourth connecting line is γ2, where 0°≤γ2≤2°.

[0037] The ratio of the length of the trailing edge to the length of the leading edge 121 is between 40% and 46%. By reasonably setting the trailing edge inclination angle and the trailing edge length, the gap leakage at the impeller outlet can be reduced, the secondary flow at the impeller outlet and the existence of the jet wake can be reduced, and the impeller efficiency can be improved. In addition, the ratio of the inlet and outlet areas of the flow channels of adjacent blades can be effectively controlled, the diffusion loss of the flow can be reduced, the high-efficiency zone range under small flow conditions can be widened, and the aerodynamic noise can be reduced at the same time.

[0038] In any of the above technical solutions, optionally, the top surface of the blade is constructed between the top of the leading edge and the top of the trailing edge, the gap between the top surface of the blade and the corresponding inner convex surface is matched, the gap between the top surface of the blade and the inner convex surface is set equal, or the gap gradually decreases along the air outlet direction.

[0039] In this technical solution, since the impeller needs to rotate in the wind shield, a clearance fit is required between the impeller blades and the inner surface of the wind shield. The clearance fit can include the following two methods: a clearance setting between the top surface of the blade and the inner convex surface. In addition, the length of the leading edge is set to be greater than the length of the trailing edge. Since the clearance at the trailing edge has a greater impact on the efficiency than that at the leading edge, the clearance between the top surface of the blade and the inner convex surface can be gradually reduced along the air outlet direction to improve the operating efficiency of the fan.

[0040] Specifically, the gap between the blades of the impeller and the inner surface of the wind shield is greater than or equal to 0.2 mm and less than or equal to 0.3 mm.

[0041] In any of the above technical solutions, optionally, the number of blades is 7.

[0042] In any of the above technical solutions, optionally, for any axial cross-section of the side of the cone, the tangential direction of the inlet and the tangential direction of the outlet are consistent with the axial direction; a flow collecting structure is constructed on the air inlet side of the side of the cone and extends in the opposite direction of the air inlet, and the inner diameter of the flow collecting structure gradually decreases along the air inlet direction, and the impeller is located on the inner side of the side of the cone.

[0043] In this technical solution, the flow collecting structure, the inner convex surface, the outer concave surface and the second cylindrical surface are smoothly connected along the axial direction to construct the inner surface of the wind cover, and by cooperating with the impeller and the diffuser, a fan duct is constructed to improve the operating efficiency of the fan.

[0044] In any of the above technical solutions, optionally, the driving device also includes: a bearing assembly, including a rotating shaft and a sleeve nested on the rotating shaft, and multiple groups of rolling bodies arranged between the sleeve and the rotating shaft, the impeller is fixed at one end of the rotating shaft; and the motor rotor is fixed at the other end of the rotating shaft.

[0045] The rolling elements are specifically divided into two groups, and the two groups of rolling elements have the same number of rolling elements, which is 6 to 7.

[0046] In any of the above technical solutions, optionally, the outer diameter of the sleeve is greater than or equal to 12 mm and less than or equal to 14 mm; the outer diameter of the matching area on the shaft with the sleeve is greater than or equal to 4 mm and less than or equal to 6 mm.

[0047] Specifically, the shaft sleeve has an outer cylindrical surface with a diameter of 13 mm, and the section of the rotating shaft axially opposite to the shaft sleeve has an outer cylindrical surface with a diameter of 5 mm.

[0048] In any of the above technical solutions, optionally, a cavity structure is defined inside the wheel disc, a hub structure is arranged inside the cavity structure, one end of the rotating shaft is assembled with a center hole opened on the hub structure; a group of rolling bodies close to the impeller are partially or completely located in the cavity structure.

[0049] In this technical solution, a cavity structure is defined inside the wheel disc so that the wheel disc is constructed as a thin-walled structure to ensure the shrinkage consistency during impeller molding, which is beneficial to reducing the rotational inertia of the impeller and improving efficiency.

[0050] In addition, under the premise that the axial size allows, the hub structure is as close to the center of gravity of the impeller as possible, which can reduce the impact of the impeller's imbalance on the bearing, thereby improving the reliability of the impeller.

[0051] In any of the above technical solutions, optionally, the diffuser further comprises: a bearing seat, which is used to accommodate the shaft sleeve and is arranged between the shaft sleeve and the diffuser plate, and / or extends into the cavity structure.

[0052] In any of the above technical solutions, optionally, the diffuser plate, the plurality of guide vanes and the bearing seat are an integrated structure.

[0053] In this technical solution, the coaxiality of the impeller and the wind cover needs to be ensured by the dimensional chain of the matching surfaces of the bearing assembly, bearing seat, diffuser plate and wind cover. The quality of the coaxiality will directly affect the uniformity of the blade tip gap between the impeller and the wind cover, that is, the efficiency of the fan. The diffuser plate and multiple guide blades are integrated into a diffuser, which can concentrate the above-mentioned dimensional chain on as few matching parts as possible, thereby ensuring assemblability and high efficiency.

[0054] In any of the above technical solutions, optionally, the motor rotor and the stator assembly are arranged in a mutually nested manner, the stator assembly is arranged in a frame, and the frame and the bearing seat are fixedly connected axially, wherein the fan air duct along the air outlet direction also includes a first flow path formed by the inner side surface of the frame and the outer side surface of the stator assembly, and a second flow path formed by the inner side surface of the stator assembly and the outer side surface of the motor rotor.

[0055] In any of the above technical solutions, optionally, it further includes: a control board, which is fixedly arranged at the bottom of the stator assembly and is arranged opposite to the outlets of the first flow path and the second flow path.

[0056] In this technical solution, by defining the first flow path and the second flow path respectively, the driving device and the heating components on the control panel can be cooled by wind flow.

[0057] Another object of the present invention is to provide an electrical device, comprising: a fan as described in any of the above technical solutions.

[0058] Among them, the electrical equipment may specifically be a vacuum cleaner, a fan, an air cleaning device, etc.

[0059] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0061] Figure 1 A schematic cross-sectional structure diagram of a fan according to an embodiment of the present invention is shown;

[0062] Figure 2 Shows Figure 1 Schematic diagram of the assembly of the wind wheel and the driving device;

[0063] Figure 3 Shows Figure 1 Schematic diagram of the assembly of the wind wheel and the driving device;

[0064] Figure 4 An exploded schematic diagram of a fan at an air inlet perspective according to an embodiment of the present invention is shown;

[0065] Figure 5 An exploded schematic diagram of a fan at a wind outlet viewing angle according to an embodiment of the present invention is shown;

[0066] Figure 6 A schematic structural diagram of a diffuser according to an embodiment of the present invention is shown;

[0067] Figure 7 A schematic structural diagram of an impeller according to an embodiment of the present invention is shown;

[0068] Figure 8 A top view of an assembly structure of an impeller and a diffuser according to an embodiment of the present invention is shown;

[0069] Fig. 9 An angled schematic diagram of a top view of an assembly structure of an impeller and a diffuser according to an embodiment of the present invention is shown;

[0070] Fig.10 A top view of an impeller according to one embodiment of the present invention is shown.

[0071] in, Figures 1 to 10 The corresponding relationship between the reference numerals and component names in the figure is:

[0072]

[0073] DETAILED DESCRIPTION

[0074] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0075] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0076] Refer to the following Figures 1 to 10 A wind turbine according to some embodiments of the present invention is described.

[0077] Embodiment 1:

[0078] like Figure 1A fan according to an embodiment of the present invention includes: an impeller 1, a diffuser 2, a wind cover 3 and a stator assembly 4.

[0079] The impeller 1 includes a wheel disc 11, the outer surface of which is constructed as a truncated cone-shaped concave surface 112, and the diameter of one end of the wheel disc 11 is smaller than the diameter of the other end of the wheel disc 11; the diffuser 2 is coaxially arranged with the impeller 1, and the diffuser 2 includes a diffuser plate 21, one end of which is assembled with the other end of the wheel disc 11, and the outer surface of the diffuser plate 21 includes a truncated cone-shaped convex surface 202 and a first cylindrical surface 204 spliced ​​with each other, the diameter of the end of the convex surface 202 close to the impeller 1 is smaller than the diameter of the end away from the impeller 1, and the first cylindrical surface 204 is arranged away from the impeller 1 relative to the convex surface 202; the wind cover 3 is coaxially arranged with the impeller 1 The shaft is set and the cover is set on the impeller 1 and the diffuser 2. The inner surface of the wind cover 3 includes a conical side surface 31 and a second cylindrical surface 32 which are spliced ​​with each other along the axial direction. The conical side surface 31 is respectively matched with the concave curved surface 112 and an outer convex curved surface 202, and the second cylindrical surface 32 is matched with the first cylindrical surface 204 to define the fan duct Q. When the fan is running, the port defined by the wheel disc 11 and the wind cover 3 is determined as the inlet of the fan duct Q, and the port defined by the diffuser 2 and the wind cover 3 is determined as the outlet of the fan duct Q. The wind flow flows into the fan duct Q from the inlet, is driven by the impeller 1, and is diffused by the diffuser 2, and then flows out of the fan duct Q from the outlet.

[0080] Optionally, it further comprises: a driving device, comprising a stator assembly 4, wherein the stator assembly 4 is arranged relative to the outlet of the fan air duct Q so that the wind flow out of the fan air duct Q is directly blown toward the stator assembly.

[0081] Optionally, the truncated cone side surface 31 includes a first side surface arranged opposite to the inner concave surface 112 and a second side surface arranged opposite to the outer convex surface 202, the first side surface is constructed as a truncated cone-shaped inner convex surface 312, and the second side surface is constructed as a truncated cone-shaped outer concave surface 314.

[0082] In the description of the following embodiments of the present application, the air inlet direction is determined as upward, and the air outlet direction is determined as downward.

[0083] Specifically, the impeller 1 has a wheel disc 11, the outer surface of which is formed as a smooth concave curved surface 112 with a gradually increasing diameter extending from the impeller inlet end 123a to the impeller outlet end 123b, and the tangent direction of the impeller outlet end 123b points radially outward and downward. The diffuser 2 includes a diffuser disc 21, which has a concentrically arranged outer convex curved surface 202 and a first cylindrical surface 204, is coaxial with the impeller 1 and is roughly arranged at the lower part of the impeller; wherein the outer convex curved surface 202 gradually increases in diameter from the outer convex curved surface inlet end 202a to the outer convex curved surface outlet end 202b, the diameter of the outer convex curved surface inlet end 202a is slightly larger than the diameter of the impeller outlet end 123b, and is roughly arranged on the tangent extension line of the impeller outlet end 123b, and the outer convex curved surface outlet end 202b has the same diameter as the outer circumferential surface of the first cylindrical surface 204 and is integrally connected in a smooth transition.

[0084] The wind shield 3 has a truncated cone side surface 31 coaxially arranged on the outer surface of the wheel disc 11 and the radial outer side of the diffuser disc 21, and a second cylindrical surface 32 arranged radially outside the first cylindrical surface 204. The truncated cone side surface 31 is formed as a curved surface with a gradually increasing diameter extending from the truncated cone side inlet end 316 to the truncated cone side outlet end 318, wherein the portion roughly arranged radially outside the impeller is formed as an inner convex curved surface 312, and the portion roughly arranged radially outside the outer convex curved surface 202 is formed as an outer concave curved surface 314; the tangent directions of the truncated cone side inlet end 316 and the truncated cone side outlet end 318 are roughly arranged along the axial direction; the truncated cone side outlet end 318 has the same diameter as the inner surface of the second cylindrical surface 32 and is connected in an integrated smooth transition, and the axial position is roughly equal to the outer convex curved surface outlet end 202b. The inner concave curved surface 112, the outer convex curved surface 202 and the truncated cone side surface 31, the first cylindrical surface 204 and the second cylindrical surface 32 form a fan air duct Q.

[0085] In any of the above embodiments, optionally, the end of the outer convex surface 202 close to the impeller 1 is located on the tangential extension line of the other end of the wheel disc 11 , or is arranged close to the tangential extension line of the other end of the wheel disc 11 .

[0086] Specifically, the fan air duct Q is an annular air cavity composed of the concave surface 112 of the impeller, the convex surface 202 of the diffuser, the outer cylindrical surface of the first cylindrical surface 204, the inner cylindrical surface of the second cylindrical surface 32 of the wind cover, and the truncated cone side surface 31. The upper section of the air cavity is set with a variable cross section, and the lower section is set with a constant cross section. The fluid enters the air duct Q roughly axially from the annular space composed of the small mouth end of the fan, i.e., the impeller inlet end 123a and the truncated cone side inlet end 316 of the wind cover, and changes the direction and kinetic energy of the fluid through the space formed by the concave surface 112 and the convex surface 312. Then, the dynamic pressure is converted into static pressure through the diffuser space formed by the convex surface 202 and the concave surface 314, and the fluid is guided radially outward and downward at the same time. Finally, the fluid is led out of the air duct through the annular air cavity composed of the inner and outer ring arms. The medium in the entire air duct Q flows very smoothly, reducing the impact loss and separation loss.

[0087] Embodiment 2:

[0088] like Figure 6 As shown, in any of the above embodiments, optionally, the diffuser further includes: a plurality of guide vanes 22, which are evenly distributed on the outer surface of the diffuser disk 21 along the circumferential direction and extend radially outward, the guide vanes 22 include a first section of blades 221 arranged on the outer convex curved surface 202, and a second section of blades 222 arranged on the first cylindrical surface 204, the first section of blades 221 and the second section of blades 222 are an integrated structure, the top surface of the first section of blades 221 is arranged in contact with the truncated cone side surface 31, and the top surface of the second section of blades 222 is arranged in contact with the second cylindrical surface 32, wherein, as Figure 8 As shown, the end of the guide vane 22 close to the wheel disk 11 is determined as the air inlet end 231, and the end away from the wheel disk 11 is determined as the air outlet end 232. The air inlet end is located at the rear side of the air outlet end 232 along the rotation direction of the impeller 1.

[0089] Specifically, a plurality of guide vanes 22 are evenly distributed along the axial direction and are integrally arranged on the diffuser 2. The guide vanes are divided into two sections, an upper section and an lower section. The first section of blades 221 are integrally arranged on the outer convex curved surface 202 and extend radially outward to completely fit with the outer concave curved surface 314. The second section of blades 222 are integrally arranged on the first cylindrical surface 204 and extend radially outward to completely fit with the inner surface of the second cylindrical surface 32. The air inlet end 231 of the guide vane 22 is rearward relative to the air outlet end 232 along the rotation direction R.

[0090] Specifically, the diffuser 2 has a convex curved surface 202 of variable cross-section and a first cylindrical surface 204 of equal cross-section, and the wind shield 3 has a concave curved surface 314 of variable cross-section and a second cylindrical surface 32 of equal cross-section. The spiral guide vane 22 is integrally arranged with the diffuser 2, and the inner side of the first section of the blade 221 is located on the convex curved surface 202 of variable cross-section, and the outer side is completely fitted with the concave curved surface 314 of variable cross-section on the wind shield 3; the inner side of the second section of the blade 222 is located on the outer surface of the first cylindrical surface 204 of equal cross-section, and the outer side is completely fitted with the second cylindrical surface 32 of equal cross-section on the wind shield 3. The function of the convex curved surface 202 is to guide the fluid at the outlet end of the impeller into the annular wind cavity radially outward and below. The guide vane 22 is partially arranged on the convex curved surface 202, so that a longer diffusion length can be obtained in the air duct of the same axial length, and a better diffusion effect can be achieved.

[0091] In other words, the axial space of the entire machine can be compressed while ensuring that the pressure diffusion effect remains unchanged.

[0092] Since the inner and outer diameters of the guide vanes are variable, the guide vanes and the inner and outer ring arms cannot form an integrated part for mold production. The guide vanes and the inner ring arms are integrated to ensure the manufacturability of the product. At the same time, the truncated cone side surface 31 and the second cylindrical surface 32 of the wind shield 3 are integrated to ensure a smooth transition of the outer surface of the air duct, avoiding the influence caused by the assembly connection between the inner circumference of the wind shield and the second cylindrical surface 32, and ensuring the smoothness of the medium flow.

[0093] In any of the above embodiments, optionally, the side surface 223 of the air inlet end 231 is constructed as a convex structure; when the impeller 1 rotates, the windward surface of the guide vane 22 is determined as the pressure surface 224, and the leeward surface of the guide vane 22 is determined as the back pressure surface 225, the pressure surface 224 is constructed as a convex structure, and the back pressure surface 225 is constructed as a concave structure.

[0094] In any of the above embodiments, optionally, the thickness of the guide vane 22 gradually increases from an end close to the wheel disc 11 to an end away from the wheel disc 11 .

[0095] Specifically, the side surface 223 of the guide vane inlet end is a smooth curved surface convex upward, the guide vane pressure surface 224 located downstream in the rotation direction is a convex surface, and the guide vane back pressure surface 225 located upstream in the rotation direction is a concave surface, and the guide vane has a thickness that gradually increases from the inlet end to the outlet end. The above guide vane design ensures the uniformity of the airflow at the inlet end, which is conducive to reducing the flow loss along the way and the impact loss at the outlet end.

[0096] In any of the above embodiments, optionally, in the radial direction, the top 231a of the air inlet end is arranged close to the wind cover 3 relative to the root 231b of the air inlet end, and in the axial direction, the top 231a of the air inlet end is arranged close to the impeller 1 relative to the root 231b of the air inlet end.

[0097] Specifically, the air outlet end 232 is substantially arranged along the radial direction, and the top 231 b of the air inlet end is arranged radially outside and above the root 231 a of the air inlet end.

[0098] In this embodiment, the wind flow is discharged from the rotating impeller 1 into the diffuser 2. By limiting the relative position relationship between the top 231a and the root 231b on the air inlet end, the root to the top of the air inlet end of the guide vane 22 is extended obliquely in the direction of the air inlet, which is beneficial to improving the uniformity of the wind flow introduced into the diffuser 2 to reduce impact loss. In addition, the air outlet direction of the guide vane is consistent with the radial direction, or has a small deviation, so as to ensure the flow direction of the diffuser outlet air flow.

[0099] Specifically, the fluid flows outward and downward from the impeller outlet end in the radial direction, and the guide vane inlet end is tilted radially outward and upward, and is basically arranged perpendicular to the fluid direction, which effectively ensures the uniformity of the gas at the guide vane inlet end and reduces the impact loss. At the same time, the air outlet end 232 is arranged roughly in the radial direction to ensure the flow direction of the diffuser outlet fluid.

[0100] In any of the above embodiments, the air outlet end 232 is optionally arranged close to the impeller 1 relative to the free end of the first cylindrical surface 204, that is, the air outlet end 232 is higher than the lower end of the first cylindrical surface 204 and the second cylindrical surface 32. The guide vane 22 is completely located in the annular air cavity composed of the convex curved surface 202, the first cylindrical surface 204, the concave curved surface 314, and the second cylindrical surface 32 in the axial direction, which can ensure the uniformity of the air flow at the inlet and outlet of the guide vane, and avoid the influence of other structural features on the fluid flow.

[0101] In any of the above embodiments, optionally, an annular protrusion structure 114 is further provided at the other end of the wheel disc 11; a groove structure 24 is provided on the end surface of the diffuser disc 21 in an area corresponding to the annular protrusion structure 114, so that one end of the diffuser disc 21 is assembled with the other end of the wheel disc 11 by adapting the annular protrusion structure 114 to the groove structure 24.

[0102] Specifically, the diffuser 2 has a groove structure 24 extending downward from the convex curved surface inlet end 202a, and the impeller has an annular protrusion structure 114 extending downward from the impeller outlet end 123b. The annular protrusion structure 114 is at least partially located inside the groove structure 24 and is fitted with a small gap.

[0103] Since the impeller 1 rotates at high speed and the diffuser 2 is fixed, the two must be matched with a clearance. When the fluid flows from the inner concave surface 112 to the outer convex surface 202, it will inevitably enter the gap between the two and cause leakage loss. A small clearance fit can reduce this leakage, thereby improving efficiency. At the same time, the annular protrusion structure 114 is located below the fluid working surface and can be used as an impeller balance ring for balancing and de-weighting. There is no need to set a separate impeller end balance ring, which reduces the number of parts, simplifies the assembly process, and reduces costs.

[0104] Optionally, 12 or 18 guide vanes 22 are evenly spaced apart on the diffuser 2 in the circumferential direction.

[0105] Embodiment three:

[0106] like Figure 7 As shown, in any of the above embodiments, optionally, the impeller 1 further includes: a plurality of blades 12, which are evenly distributed on the outer surface of the wheel disk 11 along the circumferential direction, the leading edge 121 of the blade 12 is arranged in front of the trailing edge 122 of the blade 12 along the rotation direction, the side surface 121c of the leading edge 121 is constructed as an outward convex surface, in the radial direction, the top of the leading edge 121 is arranged close to the wind cover 3 relative to the root of the leading edge 121, in the axial direction, the top of the leading edge 121 is arranged close to the inlet of the fan air duct Q relative to the root of the leading edge 121, and the top of the leading edge 121 is arranged close to the diffuser 2 relative to one end of the wheel disk 11 and one end of the cone side surface 31.

[0107] Specifically, the impeller 1 also has a plurality of blades 12 spaced apart on the concave curved surface 112, the blades 12 including a leading edge 121 located at the inlet end and a trailing edge 122 located at the outlet end, wherein the leading edge 121 is arranged in front of the trailing edge 122 along the rotation direction R; the blades 12 intersect with the concave curved surface 112 to form a root 124 of the blade, and the blades 12 extend in a direction away from the concave curved surface 112 and form a top 123 of the blade at the maximum outer diameter.

[0108] Furthermore, the top 121b of the leading edge is arranged radially outward and upward relative to the root 121a of the leading edge, and the top 121b of the leading edge is located below the impeller inlet end 123a and the cone side inlet end 316.

[0109] Optionally, the angle α between the imaginary straight line where the leading edge 121 is located and the axis is within the range of 76°±2°.

[0110] Specifically, the fluid first enters the flow channel through the impeller inlet end 123a and the truncated cone side inlet end 316, obtains a relatively uniform flow field, and then enters the independent flow channel space formed by two adjacent blades through the leading edge 121, avoiding the influence of the flow field change at the inlet end on the fluid movement between the blades. At the same time, since the leading edge 121 starts from the root 121a of the leading edge and extends radially outward and upward, the fluid flows into the blade in an inclined direction, effectively controlling the wind volume and pressure at the inlet end of the blade and reducing the loss of the fluid at the inlet end; at the same time, it can ensure that the streamline length of the top 123 of the blade is slightly larger than the streamline length of the root 124 of the blade, so that the fluid has a relatively uniform flow state at the outlet.

[0111] like Fig.10 As shown, optionally, the projection of the leading edge 121 on the plane perpendicular to the axis direction satisfies: the root 121a of the leading edge is located in front of the root 121a of the leading edge along the rotation direction R, and the angles between the line connecting the root 121a of the leading edge and the axis and the line connecting the top 121b of the leading edge and the axis satisfy 0°≤γ1≤5°.

[0112] The leading edge is arranged roughly in the radial direction, which reduces the fluid loss at the inlet end; the small leading angle at the top of the edge is conducive to the fluid drainage and ensures the manufacturability of the impeller.

[0113] Optionally, the leading edge 121 is a smooth curved surface protruding toward the inlet end, smoothly connecting the pressure surface 125 and the suction surface 126, and the blades extend forward toward the suction port and become thinner, which can increase the blade path length while reducing the relative velocity diffusion.

[0114] In any of the above embodiments, optionally, the root of the trailing edge 122 extends to the other end of the wheel disc 11, and the top of the trailing edge 122 is arranged axially opposite to the root of the trailing edge 122 close to the inlet of the fan duct Q, and the trailing edge 122 and the outer circumferential surface of the annular protrusion structure 114 are on the same circumferential surface, and the height of the trailing edge 122 is less than the height of the leading edge 121.

[0115] Specifically, the root 122a of the trailing edge 122 is located on the impeller outlet end 123b, and the top 122b of the trailing edge is roughly arranged axially above the root 122a of the trailing edge. The trailing edge 122 and the outer peripheral surface of the annular protrusion 13 form the same cylindrical surface, and the length of the trailing edge 122 is less than the length of the leading edge 121.

[0116] like Fig.10 As shown, optionally, the projection of the trailing edge 122 on the plane perpendicular to the axis satisfies: the angle between the line between the top 122b of the trailing edge and the axis and the angle between the line between the root 122a of the trailing edge and the axis satisfies 0≤γ2≤2°.

[0117] The length of the trailing edge 122 is within the range of 40% to 46% of the length of the leading edge 121. Reasonable setting of the trailing edge inclination angle and the trailing edge length can reduce the gap leakage at the impeller outlet, reduce the secondary flow at the impeller outlet and the existence of the jet wake, and improve the impeller efficiency. At the same time, the ratio of the inlet and outlet areas of the flow channels of adjacent blades can be effectively controlled, the diffusion loss of the flow can be reduced, the high-efficiency area under small flow conditions can be widened, and the aerodynamic noise can be reduced.

[0118] In any of the above embodiments, optionally, the top surface of the blade 12 is constructed between the top of the leading edge 121 and the top of the trailing edge 122, the top surface of the blade 12 is gapped with the corresponding inner convex surface, the gap between the top surface of the blade and the inner convex surface is set equal, or the gap gradually decreases along the air outlet direction.

[0119] Specifically, the blade 12 also has a top 123 of the blade extending from the root 121a of the leading edge to the top 122b of the trailing edge. The imaginary curved surface obtained by rotating the top 123 of the blade around the axis is matched with the inner convex curved surface 312 with a small gap, and the gap is set equally or gradually decreases from top to bottom.

[0120] Specifically, since the impeller and the wind shield rotate at a relatively high speed, a clearance is required between the two. If the clearance is too large, the efficiency of the air duct will be seriously affected, and if the clearance is too small, the difficulty of assembly will be greatly increased. Optionally, for the embodiment of the present invention, the clearance between the blades 12 of the impeller 1 and the inner surface of the wind shield 3 is greater than or equal to 0.2 mm, and less than or equal to 0.3 mm is most suitable. At the same time, since the leading edge length is greater than the trailing edge length, the effect of the clearance at the trailing edge on the efficiency will be greater than that at the leading edge. Therefore, it is ensured that the clearance is gradually reduced from top to bottom to effectively improve the efficiency of the fan.

[0121] like Fig. 9 As shown, optionally, the projection of the root 124 of the blade on the plane perpendicular to the axis direction satisfies: the wrap angle θ1 is within the range of 120°±3°, and the projection of the top 123 of the blade on the plane perpendicular to the axis direction satisfies: the wrap angle θ2 is within the range of 123°±3°.

[0122] Optionally, θ2 ≥ θ1.

[0123] Specifically, the larger the blade wrap angle, the smaller the flow separation and vortex in the flow channel, the closer the flow is to the blade profile, and the higher the speed is for the same impeller diameter; however, too large a blade wrap angle will cause greater friction loss, the high efficiency point will move toward the direction of small flow, and it will also cause demolding difficulties. The wrap angle range given in the present invention can make the impeller work efficiently within the speed range of 100,000 to 150,000 rpm.

[0124] Optionally, the projection of the root 124 of the blade on the plane in the direction perpendicular to the axis satisfies: the inlet placement angle β1 is within the range of 23.5°±3°; the outlet placement angle β2 is within the range of 33.5±3°; the projection of the top 123 of the blade on the plane in the direction perpendicular to the axis satisfies: the inlet placement angle β3 is within the range of 0° to 3°; the outlet placement angle β4 is within the range of 28.5±3°.

[0125] Specifically, the choice of inlet placement angle will affect the quality of the flow state when the fluid enters the impeller flow channel. A suitable inlet placement angle can reduce the displacement effect of the blade root inlet, increase the flow area, and avoid serious flow separation at the suction surface inlet, reducing flow loss. The choice of outlet placement angle will affect the vacuum degree of the fan; reducing the outlet placement angle while reducing the outer diameter of the impeller is an effective measure to improve the efficiency of the centrifugal fan. Since the operating speed of the impeller in this embodiment can reach 150,000 rpm, an excessively large impeller diameter will cause insufficient structural strength and the impact of unbalanced mass on the rotor assembly. However, if the outlet placement angle is too small, it will affect the manufacturability of the product.

[0126] By selecting the above-mentioned inlet and outlet placement angles, the inlet and outlet fluid states of the impeller can be kept uniform within the speed range of 100,000 to 150,000 rpm, reducing fluid losses, improving the vacuum degree and efficiency of the fan, while reducing the outer diameter of the impeller to ensure strength and manufacturability.

[0127] Optionally, the maximum diameter of the impeller 1 does not exceed 32 mm.

[0128] like Figure 3 As shown, optionally, the inflow angle δ1 at the upper end of the concave curved surface 112 is within the range of 4°±2°, and the outflow angle δ2 at the lower end is within the range of 57.5°±2°.

[0129] Optionally, the thickness of the blade 12 gradually increases from the leading edge 121 to the trailing edge 122 , and the ratio of the leading edge thickness to the trailing edge thickness is not less than 80%.

[0130] Optionally, seven blades 12 are distributed on the impeller 1 at equal intervals in the circumferential direction.

[0131] In any of the above embodiments, optionally, for any axial cross-section of the conical side 31, the tangential direction of the inlet and the tangential direction of the outlet are consistent with the axial direction; a collecting structure 33 is constructed on the air inlet side of the conical side 31 and extends in the opposite direction of the air inlet, and the inner diameter of the collecting structure 33 gradually decreases along the air inlet direction, and the impeller 1 is located on the inner side of the conical side 31.

[0132] Specifically, the upper end of the wind shield 3 is provided with a flow collecting structure 33 whose diameter gradually decreases from top to bottom, the lowermost end of the flow collecting structure 33 is arranged to coincide with the inlet end 316 of the truncated cone side, and the flow collecting inlet end 331 is arranged axially above the impeller inlet end 123a. The flow collecting surface of the wind shield enables the fluid to establish a uniform velocity field and fluid field before entering the impeller flow channel, which can effectively improve the efficiency of the fan.

[0133] Specifically, the flow collecting structure 33 of the wind hood, the truncated cone side surface 31 and the inner surface of the second cylindrical surface 32 together constitute the inner surface of the wind hood, and form the outer surface of the wind hood toward the outside. The outer surface of the wind hood is a thin-walled structure.

[0134] Embodiment 4:

[0135] like Figure 5 As shown, according to an embodiment of the present invention, the fan also has a bearing assembly 5, including a rotating shaft 51 and a sleeve 52 nested on the rotating shaft 51, and a plurality of rolling bodies 53 arranged between the sleeve 52 and the rotating shaft 51. The impeller 1 is fixed at one end of the rotating shaft 51; the motor rotor 6 is fixed at the other end of the rotating shaft 51.

[0136] The rolling elements 53 are specifically divided into two groups. The two groups of rolling elements have the same number of rolling elements, which is 6 to 7.

[0137] The bearing assembly 5 comprises a sleeve 52 and a rotating shaft 51 which are concentrically nested. The rotating shaft 51 passes through the sleeve 52 and extends to both ends. The impeller 1 and the rotor 6 are respectively fixedly arranged at the upper end and the lower end of the rotating shaft 51 extending out of the sleeve 52, and are arranged approximately in parallel with the sleeve in the axial direction. Two groups of rolling bodies 53 are arranged axially at intervals between the sleeve 52 and the rotating shaft 51, and each group of rolling bodies 53 is evenly arranged between the sleeve 52 and the rotating shaft 51 along the circumferential direction.

[0138] Optionally, in any of the above embodiments, optionally, the outer diameter of the sleeve 52 is greater than or equal to 12 mm and less than or equal to 14 mm; the outer diameter of the mating area on the shaft 51 with the sleeve 52 is greater than or equal to 4 mm and less than or equal to 6 mm.

[0139] Specifically, the sleeve 52 has an outer cylindrical surface with a diameter of 13 mm, and the section of the rotating shaft 51 axially opposite to the sleeve 52 has an outer cylindrical surface with a diameter of 5 mm.

[0140] Optionally, the axial span L between the two sets of rolling elements is between 16 and 18 mm;

[0141] Optionally, the axial span L between the two groups of rolling elements is between 10 and 12 mm.

[0142] Furthermore, grooves are arranged axially at intervals on the outer peripheral surface of the rotating shaft 51, and the span of the grooves is consistent with the span L of the rolling elements, and two groups of rolling elements are arranged in the grooves respectively. The raceways of the rolling elements are directly opened on the shaft, which can save the radial dimension occupied by the inner ring of the bearing assembly, and further reduce the center distance of the rolling elements while keeping the shaft diameter unchanged, which can effectively increase the limit speed of the bearing.

[0143] Optionally, the center distance of the rolling elements 53 is 6.4 mm.

[0144] According to an embodiment of the present invention, grooves are arranged axially at intervals on the inner circumference of the sleeve 52, and the span of the grooves is consistent with the rolling body span L, and two groups of rolling bodies are arranged in the grooves respectively. The raceway of the rolling body is directly opened on the sleeve, which can save the radial dimension occupied by the outer ring of the bearing assembly, so that the sleeve has a larger thickness and improves the overall rigidity; or further reduce the outer diameter of the sleeve and reduce the weight of the assembly.

[0145] According to another embodiment of the present invention, a first outer ring and a second outer ring are fixedly disposed inside the two ends of the sleeve 52, grooves are disposed on the inner circumference of the outer rings, and two groups of rolling elements are disposed in the grooves. The outer ring and the sleeve of this structure are assembled, and the axial distance between the two outer rings can be adjusted to control the clearance and apply the preload, which reduces the machining accuracy requirements for the sleeve.

[0146] Optionally, the rotating shaft 51 is a through shaft with a diameter of 5 mm, and a plurality of grooves are provided on the through shaft for mounting rolling elements and accommodating adhesives. The through shaft is easier to process than a stepped shaft, and has a higher processing accuracy than a stepped shaft. It can also avoid the local features such as the undercut groove brought by the stepped shaft that are prone to stress concentration, thereby improving rigidity and strength.

[0147] Optionally, the rolling element 53 and the rotating shaft 51 are both made of metal. The bearing assembly made of metal can run stably at a working speed of 150,000 rpm, and is economical.

[0148] Optionally, the rotating shaft 51 is made of metal and the rolling element 53 is made of ceramic. The metal through shaft with a diameter of 5 mm has a certain rigidity and can be applied to the design requirements of most small high-speed fans. The bearing assembly with ceramic balls can stably operate at an operating speed of 160,000 rpm to 170,000 rpm, which can increase the maximum speed and has a certain economy.

[0149] Optionally, the two groups of rolling elements have the same number of rolling elements, which is 6 to 7.

[0150] Embodiment five:

[0151] like Figure 2As shown, according to an embodiment of the present invention, in any of the above embodiments, optionally, a cavity structure is defined inside the wheel disc 11, a hub structure 116 is provided in the cavity structure, one end of the rotating shaft 51 is assembled with a center hole provided on the hub structure 116; a group of rolling bodies 503 close to the impeller 1 are partially or completely in the cavity structure.

[0152] Specifically, the wheel disc 11 and the annular protrusion structure 114 are thin-walled structures, and a hub structure 116 extending downward from the impeller inlet end 123a and not exceeding the impeller outlet end 123b is provided inside, which is used to accommodate the upper end of the fixed rotating shaft 51; the wheel disc 11 and the annular protrusion structure 114 form a cavity 118 inwardly, and the rolling element group 53a near the impeller end is partially or completely located inside the cavity 118. The thin-walled structure design can ensure the shrinkage consistency during impeller molding, while reducing the rotational inertia of the impeller and improving efficiency. At the same time, under the premise that the axial size allows, the support position is as close to the center of gravity of the impeller as possible, which can reduce the impact of the impeller imbalance on the bearing, thereby improving the reliability of the component.

[0153] Optionally, a small hole 116b is further provided on the hub structure 116. The diameter of the small hole 116b is smaller than the diameter of the mounting hole 116a, and the small hole 116b axially penetrates the hub structure 116. The provision of the small hole 116b, on the one hand, serves to vent air when the shaft is installed, thereby preventing assembly errors caused by the closed hole; and on the other hand, it can reduce material and rotational inertia.

[0154] One end of the rolling element group 53a near the upper part of the rotating shaft 51 passes through the impeller outlet end 123b and is fixedly connected to the mounting hole 116a. The combined length of the shaft and the hole is not less than 6mm and not more than 10mm. Under the premise of ensuring positioning reliability, the axial space is fully utilized.

[0155] According to a fan of one embodiment of the present invention, the diffuser 2 also includes: a bearing seat 23, the bearing seat 23 is used to accommodate the shaft sleeve 52, and is arranged between the shaft sleeve 52 and the diffuser plate 21, and / or extends into the cavity structure, the bearing seat 26 is roughly fixedly arranged on the radial inner side of the first cylindrical surface 204 and the outer convex surface 202, and partially protrudes upward into the cavity 118.

[0156] Optionally, the diffuser plate 21, the plurality of guide vanes 22 and the bearing seat 23 are an integrated structure.

[0157] The coaxiality of the impeller 1 and the wind cover 3 needs to be ensured by the dimension chain of the matching surfaces of the bearing assembly 5, the bearing seat 23, the diffuser plate 21 and the wind cover 3. The quality of the coaxiality will directly affect the uniformity of the blade tip gap between the impeller and the wind cover, that is, the efficiency of the fan. The diffuser plate 21 and the multiple guide blades 22 are integrally arranged as the diffuser 2, which can concentrate the above-mentioned dimension chain on as few matching parts as possible, thereby ensuring assemblability and high efficiency.

[0158] Furthermore, the outer diameter of the bearing seat 26 is smaller than the inner diameter of the first cylindrical surface 204 , and a plurality of reinforcing ribs are evenly distributed along the circumferential direction between the two.

[0159] According to a fan of one embodiment of the present invention, the motor rotor 6 and the stator assembly 4 are arranged in a mutually nested manner, the stator assembly 4 is arranged in a frame 7, and the frame 7 is fixedly connected to the bearing seat 23 along the axial direction, wherein the fan air duct Q also includes a first flow path Q1 formed by the inner side surface of the frame 7 and the outer side surface of the stator assembly 4 along the air outlet direction, and a second flow path Q2 formed by the inner side surface of the stator assembly 4 and the outer side surface of the motor rotor 6, and the rotor 6 is fixedly arranged at the lower end of the rotating shaft 51.

[0160] Optionally, the rotor 6 includes a ring-shaped magnetic ring 61 and a protective sleeve 62 fixedly sleeved on the outer circumference of the magnetic ring 61. The magnetic ring is fixedly connected to the rotating shaft 51 at one end close to the rolling element group 53b. An axial distance of at least 3 mm is reserved between the end face of the magnetic ring and the end face of the shaft sleeve to prevent the rolling element from being magnetized, thereby affecting the life of the bearing.

[0161] Optionally, the protective cover 62 has an integrally formed reinforcement part and a balancing part. Specifically, the reinforcement part is mainly arranged on the outer peripheral surface of the magnetic ring 61, has a thickness of 0.2 to 0.3 mm, and is fixed to the end surface of the magnetic ring 61 through a spinning process to protect the magnetic ring from disintegration during high-speed operation; the balancing part is arranged at the other end of the magnetic ring away from the spinning part, has a thickness of about 1 mm, and plays a role in balancing and deweighting. The protective cover structure with an integrated design can reduce the number of parts, simplify the assembly process, and reduce costs.

[0162] Optionally, the balancing part is arranged on a side away from the shaft sleeve, that is, the balancing part is arranged at the end of the rotor assembly. The balancing part away from the center of gravity of the rotor is convenient for weight removal, which can improve weight removal efficiency and reliability.

[0163] Optionally, the balancing part is arranged on a side close to the shaft sleeve, that is, the balancing part is arranged between the bearing and the magnetic ring. The balancing part close to the center of gravity of the rotor can shorten the axial length and make full use of the axial space.

[0164] Optionally, the protective cover 62 is made of non-magnetic conductive material.

[0165] According to a fan of one embodiment of the present invention, the stator assembly 4 is arranged radially outside the rotor 6 and fixedly connected to the bearing seat 26 through the frame 7. The stator assembly 4 is fixedly arranged on the axial lower side of the diffuser 2 and is at least partially located at the outlet end of the air duct Q.

[0166] like Figure 4As shown, a stator assembly 4 according to an embodiment of the present invention includes an annular stator yoke 41 and a plurality of stator teeth 42 which are circumferentially spaced on the inner side of the stator yoke 41 and extend radially inward, wherein the teeth 42 are formed as an inner surface on the radial inner side, which is clearance-matched with the outer diameter of the rotor 6 and is axially opposed to the rotor 6; the stator assembly 4 also includes a winding 43 wound on the yoke 41, wherein the maximum diameter of the winding 43 is smaller than the maximum diameter of the air duct Q, and the minimum diameter is larger than the inner surface of the stator tooth 42.

[0167] According to an embodiment of the present invention, the frame 7 has an annular housing 71 axially arranged below the second cylindrical surface 32, and the housing 71 is provided with a stator mounting portion, which inwardly fixes and accommodates the stator assembly 4. A first flow path Q1 is formed between the inner wall of the housing 71 and the winding 43, which is used to lead the fluid in the air duct Q out of the fan and cool the stator components on the flow path. At the same time, the space between the stator and the rotor forms a second flow path Q2, which is connected to the air duct Q through the upper space of the stator assembly 4, and leads the fluid in the air duct Q between the stator and the rotor to cool the heat-generating components on the flow path.

[0168] According to an embodiment of the present invention, a control panel 8 is fixedly disposed below the stator assembly 4 of the fan, and the control panel 8 is at least partially located at the outlet ends of the first flow path Q1 and the second flow path Q2.

[0169] The fluid in the air duct Q cools the stator, rotor and components on the electronic control board through two flow paths. At the same time, Q1 and Q2 are located below the air duct Q, that is, the high-speed gas is introduced into other heat-generating components for cooling only after it has completed diffusion. Therefore, it will not affect the state of the fluid in the air duct, thereby ensuring efficiency while achieving a good heat dissipation design for the entire machine.

[0170] According to an embodiment of the present invention, without changing the structure of the whole machine, the fan can adjust the speed through self-balancing under the power design requirement of 200W to 500W by adjusting the input electrical parameters, and operate efficiently in the speed range of 100000 to 150000rpm, with an efficiency exceeding 54% under the working condition of 100krpm-200W and an efficiency exceeding 52% under the working condition of 150krpm-550W.

[0171] An electrical device according to an embodiment of the present invention includes: a fan as described in any one of the above embodiments.

[0172] Among them, the electrical equipment may specifically be a vacuum cleaner, a fan, an air cleaning device, etc.

[0173] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0174] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0175] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. 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 can be combined in any one or more embodiments or examples in a suitable manner.

[0176] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fan, characterized in that: include: An impeller, comprising a wheel disc, the outer surface of which is configured as a truncated cone-shaped concave curved surface, and the diameter of one end of the wheel disc is smaller than the diameter of the other end of the wheel disc; a diffuser, arranged coaxially with the impeller, the diffuser comprising a diffuser plate, one end of the diffuser plate being arranged opposite to the other end of the wheel plate, the outer surface of the diffuser plate comprising a truncated cone-shaped outer convex surface and a first cylindrical surface spliced ​​to each other, the diameter of the end of the outer convex surface close to the impeller being smaller than the diameter of the end away from the impeller, and the first cylindrical surface being arranged away from the impeller relative to the outer convex surface; A wind cover is coaxially arranged with the impeller and covers the impeller and the diffuser, wherein the inner surface of the wind cover includes a truncated cone side surface and a second cylindrical surface which are axially connected to each other, the truncated cone side surface corresponds to the inner concave curved surface and the outer convex curved surface respectively, and the second cylindrical surface corresponds to the first cylindrical surface, so as to define an air duct of the fan. When the fan is running, the port defined by the wheel disc and the wind cover is determined as the inlet of the fan air duct, and the port defined by the diffuser and the wind cover is determined as the outlet of the fan air duct. The airflow flows into the fan air duct from the inlet, is driven by the impeller, and is diffused by the diffuser before flowing out of the fan air duct from the outlet.

2. The fan according to claim 1, characterized in that: Also includes: The driving device comprises a stator assembly, wherein the stator assembly is arranged relative to the outlet of the fan air duct so that the wind flow out of the fan air duct is directly blown toward the stator assembly.

3. The fan according to claim 2, characterized in that: The truncated cone side surface includes a first side surface arranged opposite to the inner concave curved surface, and a second side surface arranged opposite to the outer convex curved surface. The first side surface is constructed as a truncated cone-shaped inner convex curved surface, and the second side surface is constructed as a truncated cone-shaped outer concave curved surface.

4. The fan according to claim 2, characterized in that: The end of the outer convex curved surface close to the impeller is located on the tangential extension line of the other end of the wheel disc, or is arranged close to the tangential extension line of the other end of the wheel disc.

5. The fan according to claim 2, characterized in that: For any axial cross section of the side of the cone, the angle between the tangent direction on the air inlet side and the axial direction is less than or equal to a specified angle, and the angle between the tangent direction on the air outlet side and the axial direction is less than or equal to the specified angle.

6. The fan according to claim 2, characterized in that: The diffuser further comprises: A plurality of guide blades are evenly distributed on the outer surface of the diffuser disk along the circumferential direction and extend radially outward, the guide blades include a first section of blades arranged on the outer convex surface, and a second section of blades arranged on the first cylindrical surface, the first section of blades and the second section of blades are an integrated structure, the top surface of the first section of blades is fitted with the side surface of the truncated cone, and the top surface of the second section of blades is fitted with the second cylindrical surface, Among them, the end of the guide blade close to the wheel disc is determined as the air inlet end, and the end away from the wheel disc is determined as the air outlet end, and the air inlet end is located at the rear side of the air outlet end along the rotation direction of the impeller.

7. The fan according to claim 6, characterized in that: The side surface of the air inlet end is constructed as a convex structure; When the impeller rotates, the windward surface of the guide vane is determined as the pressure surface, and the leeward surface of the guide vane is determined as the back-pressure surface. The pressure surface is configured as a convex structure, and the back-pressure surface is configured as a concave structure.

8. The fan according to claim 7, characterized in that: The thickness of the guide blade gradually increases from an end close to the wheel disc to an end far away from the wheel disc.

9. The fan according to claim 6, characterized in that: In the radial direction, the top of the air inlet end is arranged close to the wind cover relative to the root of the air inlet end, and in the axial direction, the top of the air inlet end is arranged close to the impeller relative to the root of the air inlet end.

10. The fan according to claim 6, characterized in that: The air outlet end is arranged close to the impeller at a free end relative to the first cylindrical surface.

11. The fan according to claim 6, characterized in that: The number of the guide vanes is 12 or 18.

12. The fan according to claim 3, characterized in that: The other end of the wheel disc is also provided with an annular protrusion structure; A groove structure is provided on the end surface of the diffuser disc in an area corresponding to the annular protrusion structure, so that one end of the diffuser disc is assembled with the other end of the wheel disc by adapting the annular protrusion structure to the groove structure.

13. The fan according to claim 12, characterized in that: The impeller further comprises: A plurality of blades are evenly distributed on the outer surface of the wheel disc along the circumferential direction, the leading edge of the blade is arranged in front of the trailing edge of the blade along the rotation direction, the side surface of the leading edge is constructed as an outward convex surface, in the radial direction, the top of the leading edge is arranged close to the wind cover relative to the root of the leading edge, in the axial direction, the top of the leading edge is arranged close to the inlet of the fan duct relative to the root of the leading edge, and the top of the leading edge is arranged close to the diffuser relative to one end of the wheel disc and one end of the side surface of the cone.

14. The fan according to claim 13, characterized in that: The root of the trailing edge extends to the other end of the wheel disc, and the top of the trailing edge is axially arranged relative to the root of the trailing edge close to the inlet of the fan air duct. The trailing edge and the outer circumferential surface of the annular protrusion structure are on the same circumferential surface, and the height of the trailing edge is less than the height of the leading edge.

15. The fan according to claim 14, characterized in that: The top surface of the blade is constructed between the top of the leading edge and the top of the trailing edge, and the top surface of the blade is gap-matched with the corresponding inner convex surface. The top surface of the blade and the inner convex surface are set with equal gaps, or the gap gradually decreases along the air outlet direction.

16. The fan according to claim 13, characterized in that: The number of the blades is 7.

17. The fan according to claim 13, characterized in that: For any axial cross section of the side of the truncated cone, the tangent direction of the inlet and the tangent direction of the outlet are consistent with the axial direction; A flow collecting structure is constructed on the air inlet side of the truncated cone side and extends in the opposite direction of the air inlet. The inner diameter of the flow collecting structure gradually decreases along the air inlet direction. The impeller is located on the inner side of the truncated cone side.

18. The fan according to any one of claims 6 to 11, characterized in that: The driving device further comprises: A bearing assembly, comprising a rotating shaft and a sleeve nested on the rotating shaft, and a plurality of rolling elements arranged between the sleeve and the rotating shaft, wherein the impeller is fixed at one end of the rotating shaft; The motor rotor is fixed on the other end of the rotating shaft.

19. The fan according to claim 18, characterized in that: The outer diameter of the sleeve is greater than or equal to 12 mm and less than or equal to 14 mm; The outer diameter of the matching area of ​​the rotating shaft and the shaft sleeve is greater than or equal to 4 mm and less than or equal to 6 mm.

20. The fan according to claim 18, characterized in that The wheel disc defines a cavity structure inside, a hub structure is arranged inside the cavity structure, and one end of the rotating shaft is assembled with a center hole provided in the hub structure; A group of rolling elements close to the impeller is partially or completely located in the cavity structure.

21. The fan according to claim 20, characterized in that: The diffuser further comprises: A bearing seat is used to accommodate the shaft sleeve and is arranged between the shaft sleeve and the diffuser plate, and / or extends into the cavity structure.

22. The fan according to claim 21, characterized in that The diffuser plate, the plurality of guide vanes and the bearing seat are an integrated structure.

23. The fan according to claim 21, characterized in that The motor rotor and the stator assembly are mutually sleeved, the stator assembly is arranged in a frame, and the frame is fixedly connected to the bearing seat along the axial direction. Among them, the fan air duct also includes a first flow path formed by the inner side surface of the frame and the outer side surface of the stator assembly along the air outlet direction, and a second flow path formed by the inner side surface of the stator assembly and the outer side surface of the motor rotor.

24. The fan according to claim 23, characterized in that Also includes: A control board is fixedly arranged at the bottom of the stator assembly and is arranged opposite to the outlets of the first flow path and the second flow path.

25. An electrical device, characterized in that: include: A fan as claimed in any one of claims 1 to 24.

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